drm/i915/backlight: extract backlight code to a separate file
authorjsg <jsg@openbsd.org>
Fri, 9 Sep 2022 04:29:11 +0000 (04:29 +0000)
committerjsg <jsg@openbsd.org>
Fri, 9 Sep 2022 04:29:11 +0000 (04:29 +0000)
From Jani Nikula
630ab29120b5dd1c543150da5e1aa304a5aece2e in linux 5.15.y/5.15.66
6cc42fbeb150ff33b17cbf108713ca4be23994d8 in mainline linux

14 files changed:
sys/dev/pci/drm/files.drm
sys/dev/pci/drm/i915/display/g4x_dp.c
sys/dev/pci/drm/i915/display/icl_dsi.c
sys/dev/pci/drm/i915/display/intel_backlight.c [new file with mode: 0644]
sys/dev/pci/drm/i915/display/intel_backlight.h [new file with mode: 0644]
sys/dev/pci/drm/i915/display/intel_connector.c
sys/dev/pci/drm/i915/display/intel_ddi.c
sys/dev/pci/drm/i915/display/intel_dp.c
sys/dev/pci/drm/i915/display/intel_dp_aux_backlight.c
sys/dev/pci/drm/i915/display/intel_lvds.c
sys/dev/pci/drm/i915/display/intel_opregion.c
sys/dev/pci/drm/i915/display/intel_panel.c
sys/dev/pci/drm/i915/display/intel_panel.h
sys/dev/pci/drm/i915/display/vlv_dsi.c

index d0ef154..d367543 100644 (file)
@@ -1,4 +1,4 @@
-# $OpenBSD: files.drm,v 1.57 2022/04/07 07:46:04 jsg Exp $
+# $OpenBSD: files.drm,v 1.58 2022/09/09 04:29:11 jsg Exp $
 
 file   dev/pci/drm/dma-resv.c                  drm
 file   dev/pci/drm/drm_agpsupport.c            drm & agp
@@ -120,6 +120,7 @@ file        dev/pci/drm/i915/display/icl_dsi.c              inteldrm
 file   dev/pci/drm/i915/display/intel_atomic.c         inteldrm
 file   dev/pci/drm/i915/display/intel_atomic_plane.c   inteldrm
 file   dev/pci/drm/i915/display/intel_audio.c          inteldrm
+file   dev/pci/drm/i915/display/intel_backlight.c      inteldrm
 file   dev/pci/drm/i915/display/intel_bios.c           inteldrm
 file   dev/pci/drm/i915/display/intel_bw.c             inteldrm
 file   dev/pci/drm/i915/display/intel_cdclk.c          inteldrm
index a1b2c4a..6695f06 100644 (file)
@@ -7,6 +7,7 @@
 
 #include "g4x_dp.h"
 #include "intel_audio.h"
+#include "intel_backlight.h"
 #include "intel_connector.h"
 #include "intel_de.h"
 #include "intel_display_types.h"
@@ -16,7 +17,6 @@
 #include "intel_fifo_underrun.h"
 #include "intel_hdmi.h"
 #include "intel_hotplug.h"
-#include "intel_panel.h"
 #include "intel_pps.h"
 #include "intel_sideband.h"
 
index 638a00b..2601873 100644 (file)
@@ -29,6 +29,7 @@
 #include <drm/drm_mipi_dsi.h>
 
 #include "intel_atomic.h"
+#include "intel_backlight.h"
 #include "intel_combo_phy.h"
 #include "intel_connector.h"
 #include "intel_crtc.h"
diff --git a/sys/dev/pci/drm/i915/display/intel_backlight.c b/sys/dev/pci/drm/i915/display/intel_backlight.c
new file mode 100644 (file)
index 0000000..7d9415f
--- /dev/null
@@ -0,0 +1,1795 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2021 Intel Corporation
+ */
+
+#include <linux/kernel.h>
+#include <linux/pwm.h>
+
+#include "intel_backlight.h"
+#include "intel_connector.h"
+#include "intel_de.h"
+#include "intel_display_types.h"
+#include "intel_dp_aux_backlight.h"
+#include "intel_dsi_dcs_backlight.h"
+#include "intel_panel.h"
+
+/**
+ * scale - scale values from one range to another
+ * @source_val: value in range [@source_min..@source_max]
+ * @source_min: minimum legal value for @source_val
+ * @source_max: maximum legal value for @source_val
+ * @target_min: corresponding target value for @source_min
+ * @target_max: corresponding target value for @source_max
+ *
+ * Return @source_val in range [@source_min..@source_max] scaled to range
+ * [@target_min..@target_max].
+ */
+static u32 scale(u32 source_val,
+                u32 source_min, u32 source_max,
+                u32 target_min, u32 target_max)
+{
+       u64 target_val;
+
+       WARN_ON(source_min > source_max);
+       WARN_ON(target_min > target_max);
+
+       /* defensive */
+       source_val = clamp(source_val, source_min, source_max);
+
+       /* avoid overflows */
+       target_val = mul_u32_u32(source_val - source_min,
+                                target_max - target_min);
+       target_val = DIV_ROUND_CLOSEST_ULL(target_val, source_max - source_min);
+       target_val += target_min;
+
+       return target_val;
+}
+
+/*
+ * Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
+ * to [hw_min..hw_max].
+ */
+static u32 clamp_user_to_hw(struct intel_connector *connector,
+                           u32 user_level, u32 user_max)
+{
+       struct intel_panel *panel = &connector->panel;
+       u32 hw_level;
+
+       hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
+       hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
+
+       return hw_level;
+}
+
+/* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
+static u32 scale_hw_to_user(struct intel_connector *connector,
+                           u32 hw_level, u32 user_max)
+{
+       struct intel_panel *panel = &connector->panel;
+
+       return scale(hw_level, panel->backlight.min, panel->backlight.max,
+                    0, user_max);
+}
+
+u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 val)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
+
+       if (dev_priv->params.invert_brightness < 0)
+               return val;
+
+       if (dev_priv->params.invert_brightness > 0 ||
+           dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
+               return panel->backlight.pwm_level_max - val + panel->backlight.pwm_level_min;
+       }
+
+       return val;
+}
+
+void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 val)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *i915 = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       drm_dbg_kms(&i915->drm, "set backlight PWM = %d\n", val);
+       panel->backlight.pwm_funcs->set(conn_state, val);
+}
+
+u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 val)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       drm_WARN_ON_ONCE(&dev_priv->drm,
+                        panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
+
+       val = scale(val, panel->backlight.min, panel->backlight.max,
+                   panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
+
+       return intel_panel_invert_pwm_level(connector, val);
+}
+
+u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       drm_WARN_ON_ONCE(&dev_priv->drm,
+                        panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
+
+       if (dev_priv->params.invert_brightness > 0 ||
+           (dev_priv->params.invert_brightness == 0 && dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS))
+               val = panel->backlight.pwm_level_max - (val - panel->backlight.pwm_level_min);
+
+       return scale(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max,
+                    panel->backlight.min, panel->backlight.max);
+}
+
+static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
+       return intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
+}
+
+static u32 pch_get_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
+       return intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
+}
+
+static u32 i9xx_get_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 val;
+
+       val = intel_de_read(dev_priv, BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
+       if (DISPLAY_VER(dev_priv) < 4)
+               val >>= 1;
+
+       if (panel->backlight.combination_mode) {
+               u8 lbpc;
+
+               pci_read_config_byte(dev_priv->drm.pdev, LBPC, &lbpc);
+               val *= lbpc;
+       }
+
+       return val;
+}
+
+static u32 vlv_get_backlight(struct intel_connector *connector, enum pipe pipe)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
+       if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
+               return 0;
+
+       return intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
+}
+
+static u32 bxt_get_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       return intel_de_read(dev_priv,
+                            BXT_BLC_PWM_DUTY(panel->backlight.controller));
+}
+
+static u32 ext_pwm_get_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       STUB();
+       return 0;
+#ifdef notyet
+       struct intel_panel *panel = &connector->panel;
+       struct pwm_state state;
+
+       pwm_get_state(panel->backlight.pwm, &state);
+       return pwm_get_relative_duty_cycle(&state, 100);
+#endif
+}
+
+static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
+       u32 val = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, val | level);
+}
+
+static void pch_set_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       u32 tmp;
+
+       tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
+       intel_de_write(dev_priv, BLC_PWM_CPU_CTL, tmp | level);
+}
+
+static void i9xx_set_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 tmp, mask;
+
+       drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
+
+       if (panel->backlight.combination_mode) {
+               u8 lbpc;
+
+               lbpc = level * 0xfe / panel->backlight.pwm_level_max + 1;
+               level /= lbpc;
+               pci_write_config_byte(dev_priv->drm.pdev, LBPC, lbpc);
+       }
+
+       if (DISPLAY_VER(dev_priv) == 4) {
+               mask = BACKLIGHT_DUTY_CYCLE_MASK;
+       } else {
+               level <<= 1;
+               mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
+       }
+
+       tmp = intel_de_read(dev_priv, BLC_PWM_CTL) & ~mask;
+       intel_de_write(dev_priv, BLC_PWM_CTL, tmp | level);
+}
+
+static void vlv_set_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
+       u32 tmp;
+
+       tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
+       intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), tmp | level);
+}
+
+static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       intel_de_write(dev_priv,
+                      BXT_BLC_PWM_DUTY(panel->backlight.controller), level);
+}
+
+static void ext_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       STUB();
+#ifdef notyet
+       struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
+
+       pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
+       pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
+#endif
+}
+
+static void
+intel_panel_actually_set_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *i915 = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       drm_dbg_kms(&i915->drm, "set backlight level = %d\n", level);
+
+       panel->backlight.funcs->set(conn_state, level);
+}
+
+/* set backlight brightness to level in range [0..max], assuming hw min is
+ * respected.
+ */
+void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
+                                   u32 user_level, u32 user_max)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 hw_level;
+
+       /*
+        * Lack of crtc may occur during driver init because
+        * connection_mutex isn't held across the entire backlight
+        * setup + modeset readout, and the BIOS can issue the
+        * requests at any time.
+        */
+       if (!panel->backlight.present || !conn_state->crtc)
+               return;
+
+       mutex_lock(&dev_priv->backlight_lock);
+
+       drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
+
+       hw_level = clamp_user_to_hw(connector, user_level, user_max);
+       panel->backlight.level = hw_level;
+
+       if (panel->backlight.device)
+               panel->backlight.device->props.brightness =
+                       scale_hw_to_user(connector,
+                                        panel->backlight.level,
+                                        panel->backlight.device->props.max_brightness);
+
+       if (panel->backlight.enabled)
+               intel_panel_actually_set_backlight(conn_state, hw_level);
+
+       mutex_unlock(&dev_priv->backlight_lock);
+}
+
+static void lpt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       u32 tmp;
+
+       intel_panel_set_pwm_level(old_conn_state, level);
+
+       /*
+        * Although we don't support or enable CPU PWM with LPT/SPT based
+        * systems, it may have been enabled prior to loading the
+        * driver. Disable to avoid warnings on LCPLL disable.
+        *
+        * This needs rework if we need to add support for CPU PWM on PCH split
+        * platforms.
+        */
+       tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
+       if (tmp & BLM_PWM_ENABLE) {
+               drm_dbg_kms(&dev_priv->drm,
+                           "cpu backlight was enabled, disabling\n");
+               intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
+                              tmp & ~BLM_PWM_ENABLE);
+       }
+
+       tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
+}
+
+static void pch_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
+{
+       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       u32 tmp;
+
+       intel_panel_set_pwm_level(old_conn_state, val);
+
+       tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
+       intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
+
+       tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
+}
+
+static void i9xx_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
+{
+       intel_panel_set_pwm_level(old_conn_state, val);
+}
+
+static void i965_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
+{
+       struct drm_i915_private *dev_priv = to_i915(old_conn_state->connector->dev);
+       u32 tmp;
+
+       intel_panel_set_pwm_level(old_conn_state, val);
+
+       tmp = intel_de_read(dev_priv, BLC_PWM_CTL2);
+       intel_de_write(dev_priv, BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
+}
+
+static void vlv_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
+{
+       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       enum pipe pipe = to_intel_crtc(old_conn_state->crtc)->pipe;
+       u32 tmp;
+
+       intel_panel_set_pwm_level(old_conn_state, val);
+
+       tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
+       intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
+                      tmp & ~BLM_PWM_ENABLE);
+}
+
+static void bxt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
+{
+       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 tmp;
+
+       intel_panel_set_pwm_level(old_conn_state, val);
+
+       tmp = intel_de_read(dev_priv,
+                           BXT_BLC_PWM_CTL(panel->backlight.controller));
+       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
+                      tmp & ~BXT_BLC_PWM_ENABLE);
+
+       if (panel->backlight.controller == 1) {
+               val = intel_de_read(dev_priv, UTIL_PIN_CTL);
+               val &= ~UTIL_PIN_ENABLE;
+               intel_de_write(dev_priv, UTIL_PIN_CTL, val);
+       }
+}
+
+static void cnp_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
+{
+       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 tmp;
+
+       intel_panel_set_pwm_level(old_conn_state, val);
+
+       tmp = intel_de_read(dev_priv,
+                           BXT_BLC_PWM_CTL(panel->backlight.controller));
+       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
+                      tmp & ~BXT_BLC_PWM_ENABLE);
+}
+
+static void ext_pwm_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
+{
+       STUB();
+#ifdef notyet
+       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
+       struct intel_panel *panel = &connector->panel;
+
+       panel->backlight.pwm_state.enabled = false;
+       pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
+#endif
+}
+
+void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state)
+{
+       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       if (!panel->backlight.present)
+               return;
+
+       /*
+        * Do not disable backlight on the vga_switcheroo path. When switching
+        * away from i915, the other client may depend on i915 to handle the
+        * backlight. This will leave the backlight on unnecessarily when
+        * another client is not activated.
+        */
+       if (dev_priv->drm.switch_power_state == DRM_SWITCH_POWER_CHANGING) {
+               drm_dbg_kms(&dev_priv->drm,
+                           "Skipping backlight disable on vga switch\n");
+               return;
+       }
+
+       mutex_lock(&dev_priv->backlight_lock);
+
+       if (panel->backlight.device)
+               panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
+       panel->backlight.enabled = false;
+       panel->backlight.funcs->disable(old_conn_state, 0);
+
+       mutex_unlock(&dev_priv->backlight_lock);
+}
+
+static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 pch_ctl1, pch_ctl2, schicken;
+
+       pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
+       if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
+               drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
+               pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
+               intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
+       }
+
+       if (HAS_PCH_LPT(dev_priv)) {
+               schicken = intel_de_read(dev_priv, SOUTH_CHICKEN2);
+               if (panel->backlight.alternate_pwm_increment)
+                       schicken |= LPT_PWM_GRANULARITY;
+               else
+                       schicken &= ~LPT_PWM_GRANULARITY;
+               intel_de_write(dev_priv, SOUTH_CHICKEN2, schicken);
+       } else {
+               schicken = intel_de_read(dev_priv, SOUTH_CHICKEN1);
+               if (panel->backlight.alternate_pwm_increment)
+                       schicken |= SPT_PWM_GRANULARITY;
+               else
+                       schicken &= ~SPT_PWM_GRANULARITY;
+               intel_de_write(dev_priv, SOUTH_CHICKEN1, schicken);
+       }
+
+       pch_ctl2 = panel->backlight.pwm_level_max << 16;
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
+
+       pch_ctl1 = 0;
+       if (panel->backlight.active_low_pwm)
+               pch_ctl1 |= BLM_PCH_POLARITY;
+
+       /* After LPT, override is the default. */
+       if (HAS_PCH_LPT(dev_priv))
+               pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
+
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
+       intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
+                      pch_ctl1 | BLM_PCH_PWM_ENABLE);
+
+       /* This won't stick until the above enable. */
+       intel_panel_set_pwm_level(conn_state, level);
+}
+
+static void pch_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
+       u32 cpu_ctl2, pch_ctl1, pch_ctl2;
+
+       cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
+       if (cpu_ctl2 & BLM_PWM_ENABLE) {
+               drm_dbg_kms(&dev_priv->drm, "cpu backlight already enabled\n");
+               cpu_ctl2 &= ~BLM_PWM_ENABLE;
+               intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
+       }
+
+       pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
+       if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
+               drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
+               pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
+               intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
+       }
+
+       if (cpu_transcoder == TRANSCODER_EDP)
+               cpu_ctl2 = BLM_TRANSCODER_EDP;
+       else
+               cpu_ctl2 = BLM_PIPE(cpu_transcoder);
+       intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
+       intel_de_posting_read(dev_priv, BLC_PWM_CPU_CTL2);
+       intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
+
+       /* This won't stick until the above enable. */
+       intel_panel_set_pwm_level(conn_state, level);
+
+       pch_ctl2 = panel->backlight.pwm_level_max << 16;
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
+
+       pch_ctl1 = 0;
+       if (panel->backlight.active_low_pwm)
+               pch_ctl1 |= BLM_PCH_POLARITY;
+
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
+       intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
+       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
+                      pch_ctl1 | BLM_PCH_PWM_ENABLE);
+}
+
+static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                 const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 ctl, freq;
+
+       ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
+       if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
+               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
+               intel_de_write(dev_priv, BLC_PWM_CTL, 0);
+       }
+
+       freq = panel->backlight.pwm_level_max;
+       if (panel->backlight.combination_mode)
+               freq /= 0xff;
+
+       ctl = freq << 17;
+       if (panel->backlight.combination_mode)
+               ctl |= BLM_LEGACY_MODE;
+       if (IS_PINEVIEW(dev_priv) && panel->backlight.active_low_pwm)
+               ctl |= BLM_POLARITY_PNV;
+
+       intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
+       intel_de_posting_read(dev_priv, BLC_PWM_CTL);
+
+       /* XXX: combine this into above write? */
+       intel_panel_set_pwm_level(conn_state, level);
+
+       /*
+        * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
+        * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
+        * that has backlight.
+        */
+       if (DISPLAY_VER(dev_priv) == 2)
+               intel_de_write(dev_priv, BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
+}
+
+static void i965_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                 const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
+       u32 ctl, ctl2, freq;
+
+       ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
+       if (ctl2 & BLM_PWM_ENABLE) {
+               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
+               ctl2 &= ~BLM_PWM_ENABLE;
+               intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
+       }
+
+       freq = panel->backlight.pwm_level_max;
+       if (panel->backlight.combination_mode)
+               freq /= 0xff;
+
+       ctl = freq << 16;
+       intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
+
+       ctl2 = BLM_PIPE(pipe);
+       if (panel->backlight.combination_mode)
+               ctl2 |= BLM_COMBINATION_MODE;
+       if (panel->backlight.active_low_pwm)
+               ctl2 |= BLM_POLARITY_I965;
+       intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
+       intel_de_posting_read(dev_priv, BLC_PWM_CTL2);
+       intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
+
+       intel_panel_set_pwm_level(conn_state, level);
+}
+
+static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
+       u32 ctl, ctl2;
+
+       ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
+       if (ctl2 & BLM_PWM_ENABLE) {
+               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
+               ctl2 &= ~BLM_PWM_ENABLE;
+               intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
+       }
+
+       ctl = panel->backlight.pwm_level_max << 16;
+       intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), ctl);
+
+       /* XXX: combine this into above write? */
+       intel_panel_set_pwm_level(conn_state, level);
+
+       ctl2 = 0;
+       if (panel->backlight.active_low_pwm)
+               ctl2 |= BLM_POLARITY_I965;
+       intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
+       intel_de_posting_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
+       intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
+                      ctl2 | BLM_PWM_ENABLE);
+}
+
+static void bxt_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
+       u32 pwm_ctl, val;
+
+       /* Controller 1 uses the utility pin. */
+       if (panel->backlight.controller == 1) {
+               val = intel_de_read(dev_priv, UTIL_PIN_CTL);
+               if (val & UTIL_PIN_ENABLE) {
+                       drm_dbg_kms(&dev_priv->drm,
+                                   "util pin already enabled\n");
+                       val &= ~UTIL_PIN_ENABLE;
+                       intel_de_write(dev_priv, UTIL_PIN_CTL, val);
+               }
+
+               val = 0;
+               if (panel->backlight.util_pin_active_low)
+                       val |= UTIL_PIN_POLARITY;
+               intel_de_write(dev_priv, UTIL_PIN_CTL,
+                              val | UTIL_PIN_PIPE(pipe) | UTIL_PIN_MODE_PWM | UTIL_PIN_ENABLE);
+       }
+
+       pwm_ctl = intel_de_read(dev_priv,
+                               BXT_BLC_PWM_CTL(panel->backlight.controller));
+       if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
+               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
+               pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
+               intel_de_write(dev_priv,
+                              BXT_BLC_PWM_CTL(panel->backlight.controller),
+                              pwm_ctl);
+       }
+
+       intel_de_write(dev_priv,
+                      BXT_BLC_PWM_FREQ(panel->backlight.controller),
+                      panel->backlight.pwm_level_max);
+
+       intel_panel_set_pwm_level(conn_state, level);
+
+       pwm_ctl = 0;
+       if (panel->backlight.active_low_pwm)
+               pwm_ctl |= BXT_BLC_PWM_POLARITY;
+
+       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
+                      pwm_ctl);
+       intel_de_posting_read(dev_priv,
+                             BXT_BLC_PWM_CTL(panel->backlight.controller));
+       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
+                      pwm_ctl | BXT_BLC_PWM_ENABLE);
+}
+
+static void cnp_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 pwm_ctl;
+
+       pwm_ctl = intel_de_read(dev_priv,
+                               BXT_BLC_PWM_CTL(panel->backlight.controller));
+       if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
+               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
+               pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
+               intel_de_write(dev_priv,
+                              BXT_BLC_PWM_CTL(panel->backlight.controller),
+                              pwm_ctl);
+       }
+
+       intel_de_write(dev_priv,
+                      BXT_BLC_PWM_FREQ(panel->backlight.controller),
+                      panel->backlight.pwm_level_max);
+
+       intel_panel_set_pwm_level(conn_state, level);
+
+       pwm_ctl = 0;
+       if (panel->backlight.active_low_pwm)
+               pwm_ctl |= BXT_BLC_PWM_POLARITY;
+
+       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
+                      pwm_ctl);
+       intel_de_posting_read(dev_priv,
+                             BXT_BLC_PWM_CTL(panel->backlight.controller));
+       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
+                      pwm_ctl | BXT_BLC_PWM_ENABLE);
+}
+
+static void ext_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                    const struct drm_connector_state *conn_state, u32 level)
+{
+       STUB();
+#ifdef notyet
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct intel_panel *panel = &connector->panel;
+
+       pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
+       panel->backlight.pwm_state.enabled = true;
+       pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
+#endif
+}
+
+static void __intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                          const struct drm_connector_state *conn_state)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct intel_panel *panel = &connector->panel;
+
+       WARN_ON(panel->backlight.max == 0);
+
+       if (panel->backlight.level <= panel->backlight.min) {
+               panel->backlight.level = panel->backlight.max;
+               if (panel->backlight.device)
+                       panel->backlight.device->props.brightness =
+                               scale_hw_to_user(connector,
+                                                panel->backlight.level,
+                                                panel->backlight.device->props.max_brightness);
+       }
+
+       panel->backlight.funcs->enable(crtc_state, conn_state, panel->backlight.level);
+       panel->backlight.enabled = true;
+       if (panel->backlight.device)
+               panel->backlight.device->props.power = FB_BLANK_UNBLANK;
+}
+
+void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                 const struct drm_connector_state *conn_state)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
+
+       if (!panel->backlight.present)
+               return;
+
+       drm_dbg_kms(&dev_priv->drm, "pipe %c\n", pipe_name(pipe));
+
+       mutex_lock(&dev_priv->backlight_lock);
+
+       __intel_panel_enable_backlight(crtc_state, conn_state);
+
+       mutex_unlock(&dev_priv->backlight_lock);
+}
+
+#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
+static u32 intel_panel_get_backlight(struct intel_connector *connector)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 val = 0;
+
+       mutex_lock(&dev_priv->backlight_lock);
+
+       if (panel->backlight.enabled)
+               val = panel->backlight.funcs->get(connector, intel_connector_get_pipe(connector));
+
+       mutex_unlock(&dev_priv->backlight_lock);
+
+       drm_dbg_kms(&dev_priv->drm, "get backlight PWM = %d\n", val);
+       return val;
+}
+
+/* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
+static u32 scale_user_to_hw(struct intel_connector *connector,
+                           u32 user_level, u32 user_max)
+{
+       struct intel_panel *panel = &connector->panel;
+
+       return scale(user_level, 0, user_max,
+                    panel->backlight.min, panel->backlight.max);
+}
+
+/* set backlight brightness to level in range [0..max], scaling wrt hw min */
+static void intel_panel_set_backlight(const struct drm_connector_state *conn_state,
+                                     u32 user_level, u32 user_max)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 hw_level;
+
+       if (!panel->backlight.present)
+               return;
+
+       mutex_lock(&dev_priv->backlight_lock);
+
+       drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
+
+       hw_level = scale_user_to_hw(connector, user_level, user_max);
+       panel->backlight.level = hw_level;
+
+       if (panel->backlight.enabled)
+               intel_panel_actually_set_backlight(conn_state, hw_level);
+
+       mutex_unlock(&dev_priv->backlight_lock);
+}
+
+static int intel_backlight_device_update_status(struct backlight_device *bd)
+{
+       struct intel_connector *connector = bl_get_data(bd);
+       struct intel_panel *panel = &connector->panel;
+       struct drm_device *dev = connector->base.dev;
+
+       drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
+       DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
+                     bd->props.brightness, bd->props.max_brightness);
+       intel_panel_set_backlight(connector->base.state, bd->props.brightness,
+                                 bd->props.max_brightness);
+
+       /*
+        * Allow flipping bl_power as a sub-state of enabled. Sadly the
+        * backlight class device does not make it easy to differentiate
+        * between callbacks for brightness and bl_power, so our backlight_power
+        * callback needs to take this into account.
+        */
+       if (panel->backlight.enabled) {
+               if (panel->backlight.power) {
+                       bool enable = bd->props.power == FB_BLANK_UNBLANK &&
+                               bd->props.brightness != 0;
+                       panel->backlight.power(connector, enable);
+               }
+       } else {
+               bd->props.power = FB_BLANK_POWERDOWN;
+       }
+
+       drm_modeset_unlock(&dev->mode_config.connection_mutex);
+       return 0;
+}
+
+static int intel_backlight_device_get_brightness(struct backlight_device *bd)
+{
+       struct intel_connector *connector = bl_get_data(bd);
+       struct drm_device *dev = connector->base.dev;
+       struct drm_i915_private *dev_priv = to_i915(dev);
+       intel_wakeref_t wakeref;
+       int ret = 0;
+
+       with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref) {
+               u32 hw_level;
+
+               drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
+
+               hw_level = intel_panel_get_backlight(connector);
+               ret = scale_hw_to_user(connector,
+                                      hw_level, bd->props.max_brightness);
+
+               drm_modeset_unlock(&dev->mode_config.connection_mutex);
+       }
+
+       return ret;
+}
+
+static const struct backlight_ops intel_backlight_device_ops = {
+       .update_status = intel_backlight_device_update_status,
+       .get_brightness = intel_backlight_device_get_brightness,
+};
+
+int intel_backlight_device_register(struct intel_connector *connector)
+{
+       struct drm_i915_private *i915 = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       struct backlight_properties props;
+       struct backlight_device *bd;
+       const char *name;
+       int ret = 0;
+
+       if (WARN_ON(panel->backlight.device))
+               return -ENODEV;
+
+       if (!panel->backlight.present)
+               return 0;
+
+       WARN_ON(panel->backlight.max == 0);
+
+       memset(&props, 0, sizeof(props));
+       props.type = BACKLIGHT_RAW;
+
+       /*
+        * Note: Everything should work even if the backlight device max
+        * presented to the userspace is arbitrarily chosen.
+        */
+       props.max_brightness = panel->backlight.max;
+       props.brightness = scale_hw_to_user(connector,
+                                           panel->backlight.level,
+                                           props.max_brightness);
+
+       if (panel->backlight.enabled)
+               props.power = FB_BLANK_UNBLANK;
+       else
+               props.power = FB_BLANK_POWERDOWN;
+
+       name = kstrdup("intel_backlight", GFP_KERNEL);
+       if (!name)
+               return -ENOMEM;
+
+       bd = backlight_device_register(name, connector->base.kdev, connector,
+                                      &intel_backlight_device_ops, &props);
+
+       /*
+        * Using the same name independent of the drm device or connector
+        * prevents registration of multiple backlight devices in the
+        * driver. However, we need to use the default name for backward
+        * compatibility. Use unique names for subsequent backlight devices as a
+        * fallback when the default name already exists.
+        */
+       if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) {
+               kfree(name);
+               name = kasprintf(GFP_KERNEL, "card%d-%s-backlight",
+                                i915->drm.primary->index, connector->base.name);
+               if (!name)
+                       return -ENOMEM;
+
+               bd = backlight_device_register(name, connector->base.kdev, connector,
+                                              &intel_backlight_device_ops, &props);
+       }
+
+       if (IS_ERR(bd)) {
+               drm_err(&i915->drm,
+                       "[CONNECTOR:%d:%s] backlight device %s register failed: %ld\n",
+                       connector->base.base.id, connector->base.name, name, PTR_ERR(bd));
+               ret = PTR_ERR(bd);
+               goto out;
+       }
+
+       panel->backlight.device = bd;
+
+       drm_dbg_kms(&i915->drm,
+                   "[CONNECTOR:%d:%s] backlight device %s registered\n",
+                   connector->base.base.id, connector->base.name, name);
+
+out:
+       kfree(name);
+
+       return ret;
+}
+
+void intel_backlight_device_unregister(struct intel_connector *connector)
+{
+       struct intel_panel *panel = &connector->panel;
+
+       if (panel->backlight.device) {
+               backlight_device_unregister(panel->backlight.device);
+               panel->backlight.device = NULL;
+       }
+}
+#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
+
+/*
+ * CNP: PWM clock frequency is 19.2 MHz or 24 MHz.
+ *      PWM increment = 1
+ */
+static u32 cnp_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
+       return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
+                                pwm_freq_hz);
+}
+
+/*
+ * BXT: PWM clock frequency = 19.2 MHz.
+ */
+static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+       return DIV_ROUND_CLOSEST(KHz(19200), pwm_freq_hz);
+}
+
+/*
+ * SPT: This value represents the period of the PWM stream in clock periods
+ * multiplied by 16 (default increment) or 128 (alternate increment selected in
+ * SCHICKEN_1 bit 0). PWM clock is 24 MHz.
+ */
+static u32 spt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+       struct intel_panel *panel = &connector->panel;
+       u32 mul;
+
+       if (panel->backlight.alternate_pwm_increment)
+               mul = 128;
+       else
+               mul = 16;
+
+       return DIV_ROUND_CLOSEST(MHz(24), pwm_freq_hz * mul);
+}
+
+/*
+ * LPT: This value represents the period of the PWM stream in clock periods
+ * multiplied by 128 (default increment) or 16 (alternate increment, selected in
+ * LPT SOUTH_CHICKEN2 register bit 5).
+ */
+static u32 lpt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 mul, clock;
+
+       if (panel->backlight.alternate_pwm_increment)
+               mul = 16;
+       else
+               mul = 128;
+
+       if (HAS_PCH_LPT_H(dev_priv))
+               clock = MHz(135); /* LPT:H */
+       else
+               clock = MHz(24); /* LPT:LP */
+
+       return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
+}
+
+/*
+ * ILK/SNB/IVB: This value represents the period of the PWM stream in PCH
+ * display raw clocks multiplied by 128.
+ */
+static u32 pch_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
+       return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
+                                pwm_freq_hz * 128);
+}
+
+/*
+ * Gen2: This field determines the number of time base events (display core
+ * clock frequency/32) in total for a complete cycle of modulated backlight
+ * control.
+ *
+ * Gen3: A time base event equals the display core clock ([DevPNV] HRAW clock)
+ * divided by 32.
+ */
+static u32 i9xx_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       int clock;
+
+       if (IS_PINEVIEW(dev_priv))
+               clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
+       else
+               clock = KHz(dev_priv->cdclk.hw.cdclk);
+
+       return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 32);
+}
+
+/*
+ * Gen4: This value represents the period of the PWM stream in display core
+ * clocks ([DevCTG] HRAW clocks) multiplied by 128.
+ *
+ */
+static u32 i965_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       int clock;
+
+       if (IS_G4X(dev_priv))
+               clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
+       else
+               clock = KHz(dev_priv->cdclk.hw.cdclk);
+
+       return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 128);
+}
+
+/*
+ * VLV: This value represents the period of the PWM stream in display core
+ * clocks ([DevCTG] 200MHz HRAW clocks) multiplied by 128 or 25MHz S0IX clocks
+ * multiplied by 16. CHV uses a 19.2MHz S0IX clock.
+ */
+static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       int mul, clock;
+
+       if ((intel_de_read(dev_priv, CBR1_VLV) & CBR_PWM_CLOCK_MUX_SELECT) == 0) {
+               if (IS_CHERRYVIEW(dev_priv))
+                       clock = KHz(19200);
+               else
+                       clock = MHz(25);
+               mul = 16;
+       } else {
+               clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
+               mul = 128;
+       }
+
+       return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
+}
+
+static u16 get_vbt_pwm_freq(struct drm_i915_private *dev_priv)
+{
+       u16 pwm_freq_hz = dev_priv->vbt.backlight.pwm_freq_hz;
+
+       if (pwm_freq_hz) {
+               drm_dbg_kms(&dev_priv->drm,
+                           "VBT defined backlight frequency %u Hz\n",
+                           pwm_freq_hz);
+       } else {
+               pwm_freq_hz = 200;
+               drm_dbg_kms(&dev_priv->drm,
+                           "default backlight frequency %u Hz\n",
+                           pwm_freq_hz);
+       }
+
+       return pwm_freq_hz;
+}
+
+static u32 get_backlight_max_vbt(struct intel_connector *connector)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u16 pwm_freq_hz = get_vbt_pwm_freq(dev_priv);
+       u32 pwm;
+
+       if (!panel->backlight.pwm_funcs->hz_to_pwm) {
+               drm_dbg_kms(&dev_priv->drm,
+                           "backlight frequency conversion not supported\n");
+               return 0;
+       }
+
+       pwm = panel->backlight.pwm_funcs->hz_to_pwm(connector, pwm_freq_hz);
+       if (!pwm) {
+               drm_dbg_kms(&dev_priv->drm,
+                           "backlight frequency conversion failed\n");
+               return 0;
+       }
+
+       return pwm;
+}
+
+/*
+ * Note: The setup hooks can't assume pipe is set!
+ */
+static u32 get_backlight_min_vbt(struct intel_connector *connector)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       int min;
+
+       drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
+
+       /*
+        * XXX: If the vbt value is 255, it makes min equal to max, which leads
+        * to problems. There are such machines out there. Either our
+        * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
+        * against this by letting the minimum be at most (arbitrarily chosen)
+        * 25% of the max.
+        */
+       min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
+       if (min != dev_priv->vbt.backlight.min_brightness) {
+               drm_dbg_kms(&dev_priv->drm,
+                           "clamping VBT min backlight %d/255 to %d/255\n",
+                           dev_priv->vbt.backlight.min_brightness, min);
+       }
+
+       /* vbt value is a coefficient in range [0..255] */
+       return scale(min, 0, 255, 0, panel->backlight.pwm_level_max);
+}
+
+static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
+       bool alt, cpu_mode;
+
+       if (HAS_PCH_LPT(dev_priv))
+               alt = intel_de_read(dev_priv, SOUTH_CHICKEN2) & LPT_PWM_GRANULARITY;
+       else
+               alt = intel_de_read(dev_priv, SOUTH_CHICKEN1) & SPT_PWM_GRANULARITY;
+       panel->backlight.alternate_pwm_increment = alt;
+
+       pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
+       panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
+
+       pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
+       panel->backlight.pwm_level_max = pch_ctl2 >> 16;
+
+       cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
+
+       if (!panel->backlight.pwm_level_max)
+               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
+
+       if (!panel->backlight.pwm_level_max)
+               return -ENODEV;
+
+       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
+
+       panel->backlight.pwm_enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE;
+
+       cpu_mode = panel->backlight.pwm_enabled && HAS_PCH_LPT(dev_priv) &&
+                  !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) &&
+                  (cpu_ctl2 & BLM_PWM_ENABLE);
+
+       if (cpu_mode) {
+               val = pch_get_backlight(connector, unused);
+
+               drm_dbg_kms(&dev_priv->drm,
+                           "CPU backlight register was enabled, switching to PCH override\n");
+
+               /* Write converted CPU PWM value to PCH override register */
+               lpt_set_backlight(connector->base.state, val);
+               intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
+                              pch_ctl1 | BLM_PCH_OVERRIDE_ENABLE);
+
+               intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
+                              cpu_ctl2 & ~BLM_PWM_ENABLE);
+       }
+
+       return 0;
+}
+
+static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 cpu_ctl2, pch_ctl1, pch_ctl2;
+
+       pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
+       panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
+
+       pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
+       panel->backlight.pwm_level_max = pch_ctl2 >> 16;
+
+       if (!panel->backlight.pwm_level_max)
+               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
+
+       if (!panel->backlight.pwm_level_max)
+               return -ENODEV;
+
+       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
+
+       cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
+       panel->backlight.pwm_enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
+               (pch_ctl1 & BLM_PCH_PWM_ENABLE);
+
+       return 0;
+}
+
+static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 ctl, val;
+
+       ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
+
+       if (DISPLAY_VER(dev_priv) == 2 || IS_I915GM(dev_priv) || IS_I945GM(dev_priv))
+               panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
+
+       if (IS_PINEVIEW(dev_priv))
+               panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
+
+       panel->backlight.pwm_level_max = ctl >> 17;
+
+       if (!panel->backlight.pwm_level_max) {
+               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
+               panel->backlight.pwm_level_max >>= 1;
+       }
+
+       if (!panel->backlight.pwm_level_max)
+               return -ENODEV;
+
+       if (panel->backlight.combination_mode)
+               panel->backlight.pwm_level_max *= 0xff;
+
+       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
+
+       val = i9xx_get_backlight(connector, unused);
+       val = intel_panel_invert_pwm_level(connector, val);
+       val = clamp(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
+
+       panel->backlight.pwm_enabled = val != 0;
+
+       return 0;
+}
+
+static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 ctl, ctl2;
+
+       ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
+       panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
+       panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
+
+       ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
+       panel->backlight.pwm_level_max = ctl >> 16;
+
+       if (!panel->backlight.pwm_level_max)
+               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
+
+       if (!panel->backlight.pwm_level_max)
+               return -ENODEV;
+
+       if (panel->backlight.combination_mode)
+               panel->backlight.pwm_level_max *= 0xff;
+
+       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
+
+       panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
+
+       return 0;
+}
+
+static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 ctl, ctl2;
+
+       if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
+               return -ENODEV;
+
+       ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
+       panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
+
+       ctl = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe));
+       panel->backlight.pwm_level_max = ctl >> 16;
+
+       if (!panel->backlight.pwm_level_max)
+               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
+
+       if (!panel->backlight.pwm_level_max)
+               return -ENODEV;
+
+       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
+
+       panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
+
+       return 0;
+}
+
+static int
+bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 pwm_ctl, val;
+
+       panel->backlight.controller = dev_priv->vbt.backlight.controller;
+
+       pwm_ctl = intel_de_read(dev_priv,
+                               BXT_BLC_PWM_CTL(panel->backlight.controller));
+
+       /* Controller 1 uses the utility pin. */
+       if (panel->backlight.controller == 1) {
+               val = intel_de_read(dev_priv, UTIL_PIN_CTL);
+               panel->backlight.util_pin_active_low =
+                                       val & UTIL_PIN_POLARITY;
+       }
+
+       panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
+       panel->backlight.pwm_level_max =
+               intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
+
+       if (!panel->backlight.pwm_level_max)
+               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
+
+       if (!panel->backlight.pwm_level_max)
+               return -ENODEV;
+
+       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
+
+       panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
+
+       return 0;
+}
+
+static int
+cnp_setup_backlight(struct intel_connector *connector, enum pipe unused)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+       u32 pwm_ctl;
+
+       /*
+        * CNP has the BXT implementation of backlight, but with only one
+        * controller. TODO: ICP has multiple controllers but we only use
+        * controller 0 for now.
+        */
+       panel->backlight.controller = 0;
+
+       pwm_ctl = intel_de_read(dev_priv,
+                               BXT_BLC_PWM_CTL(panel->backlight.controller));
+
+       panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
+       panel->backlight.pwm_level_max =
+               intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
+
+       if (!panel->backlight.pwm_level_max)
+               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
+
+       if (!panel->backlight.pwm_level_max)
+               return -ENODEV;
+
+       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
+
+       panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
+
+       return 0;
+}
+
+static int ext_pwm_setup_backlight(struct intel_connector *connector,
+                                  enum pipe pipe)
+{
+       struct drm_device *dev = connector->base.dev;
+       struct drm_i915_private *dev_priv = to_i915(dev);
+       struct intel_panel *panel = &connector->panel;
+       const char *desc;
+       u32 level;
+
+       /* Get the right PWM chip for DSI backlight according to VBT */
+       if (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) {
+               panel->backlight.pwm = pwm_get(dev->dev, "pwm_pmic_backlight");
+               desc = "PMIC";
+       } else {
+               panel->backlight.pwm = pwm_get(dev->dev, "pwm_soc_backlight");
+               desc = "SoC";
+       }
+
+       if (IS_ERR(panel->backlight.pwm)) {
+               drm_err(&dev_priv->drm, "Failed to get the %s PWM chip\n",
+                       desc);
+               panel->backlight.pwm = NULL;
+               return -ENODEV;
+       }
+
+       panel->backlight.pwm_level_max = 100; /* 100% */
+       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
+
+#ifdef notyet
+       if (pwm_is_enabled(panel->backlight.pwm)) {
+               /* PWM is already enabled, use existing settings */
+               pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state);
+
+               level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state,
+                                                   100);
+               level = intel_panel_invert_pwm_level(connector, level);
+               panel->backlight.pwm_enabled = true;
+
+               drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n",
+                           NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period,
+                           get_vbt_pwm_freq(dev_priv), level);
+       } else {
+               /* Set period from VBT frequency, leave other settings at 0. */
+               panel->backlight.pwm_state.period =
+                       NSEC_PER_SEC / get_vbt_pwm_freq(dev_priv);
+       }
+#else
+       STUB();
+#endif
+
+       drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n",
+                desc);
+       return 0;
+}
+
+static void intel_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct intel_panel *panel = &connector->panel;
+
+       panel->backlight.pwm_funcs->set(conn_state,
+                                      intel_panel_invert_pwm_level(connector, level));
+}
+
+static u32 intel_pwm_get_backlight(struct intel_connector *connector, enum pipe pipe)
+{
+       struct intel_panel *panel = &connector->panel;
+
+       return intel_panel_invert_pwm_level(connector,
+                                           panel->backlight.pwm_funcs->get(connector, pipe));
+}
+
+static void intel_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                      const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct intel_panel *panel = &connector->panel;
+
+       panel->backlight.pwm_funcs->enable(crtc_state, conn_state,
+                                          intel_panel_invert_pwm_level(connector, level));
+}
+
+static void intel_pwm_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct intel_panel *panel = &connector->panel;
+
+       panel->backlight.pwm_funcs->disable(conn_state,
+                                           intel_panel_invert_pwm_level(connector, level));
+}
+
+static int intel_pwm_setup_backlight(struct intel_connector *connector, enum pipe pipe)
+{
+       struct intel_panel *panel = &connector->panel;
+       int ret = panel->backlight.pwm_funcs->setup(connector, pipe);
+
+       if (ret < 0)
+               return ret;
+
+       panel->backlight.min = panel->backlight.pwm_level_min;
+       panel->backlight.max = panel->backlight.pwm_level_max;
+       panel->backlight.level = intel_pwm_get_backlight(connector, pipe);
+       panel->backlight.enabled = panel->backlight.pwm_enabled;
+
+       return 0;
+}
+
+void intel_panel_update_backlight(struct intel_atomic_state *state,
+                                 struct intel_encoder *encoder,
+                                 const struct intel_crtc_state *crtc_state,
+                                 const struct drm_connector_state *conn_state)
+{
+       struct intel_connector *connector = to_intel_connector(conn_state->connector);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+       struct intel_panel *panel = &connector->panel;
+
+       if (!panel->backlight.present)
+               return;
+
+       mutex_lock(&dev_priv->backlight_lock);
+       if (!panel->backlight.enabled)
+               __intel_panel_enable_backlight(crtc_state, conn_state);
+
+       mutex_unlock(&dev_priv->backlight_lock);
+}
+
+int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
+{
+       struct drm_i915_private *dev_priv = to_i915(connector->dev);
+       struct intel_connector *intel_connector = to_intel_connector(connector);
+       struct intel_panel *panel = &intel_connector->panel;
+       int ret;
+
+       if (!dev_priv->vbt.backlight.present) {
+               if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
+                       drm_dbg_kms(&dev_priv->drm,
+                                   "no backlight present per VBT, but present per quirk\n");
+               } else {
+                       drm_dbg_kms(&dev_priv->drm,
+                                   "no backlight present per VBT\n");
+                       return 0;
+               }
+       }
+
+       /* ensure intel_panel has been initialized first */
+       if (drm_WARN_ON(&dev_priv->drm, !panel->backlight.funcs))
+               return -ENODEV;
+
+       /* set level and max in panel struct */
+       mutex_lock(&dev_priv->backlight_lock);
+       ret = panel->backlight.funcs->setup(intel_connector, pipe);
+       mutex_unlock(&dev_priv->backlight_lock);
+
+       if (ret) {
+               drm_dbg_kms(&dev_priv->drm,
+                           "failed to setup backlight for connector %s\n",
+                           connector->name);
+               return ret;
+       }
+
+       panel->backlight.present = true;
+
+       drm_dbg_kms(&dev_priv->drm,
+                   "Connector %s backlight initialized, %s, brightness %u/%u\n",
+                   connector->name,
+                   enableddisabled(panel->backlight.enabled),
+                   panel->backlight.level, panel->backlight.max);
+
+       return 0;
+}
+
+void intel_panel_destroy_backlight(struct intel_panel *panel)
+{
+       /* dispose of the pwm */
+       if (panel->backlight.pwm)
+               pwm_put(panel->backlight.pwm);
+
+       panel->backlight.present = false;
+}
+
+static const struct intel_panel_bl_funcs bxt_pwm_funcs = {
+       .setup = bxt_setup_backlight,
+       .enable = bxt_enable_backlight,
+       .disable = bxt_disable_backlight,
+       .set = bxt_set_backlight,
+       .get = bxt_get_backlight,
+       .hz_to_pwm = bxt_hz_to_pwm,
+};
+
+static const struct intel_panel_bl_funcs cnp_pwm_funcs = {
+       .setup = cnp_setup_backlight,
+       .enable = cnp_enable_backlight,
+       .disable = cnp_disable_backlight,
+       .set = bxt_set_backlight,
+       .get = bxt_get_backlight,
+       .hz_to_pwm = cnp_hz_to_pwm,
+};
+
+static const struct intel_panel_bl_funcs lpt_pwm_funcs = {
+       .setup = lpt_setup_backlight,
+       .enable = lpt_enable_backlight,
+       .disable = lpt_disable_backlight,
+       .set = lpt_set_backlight,
+       .get = lpt_get_backlight,
+       .hz_to_pwm = lpt_hz_to_pwm,
+};
+
+static const struct intel_panel_bl_funcs spt_pwm_funcs = {
+       .setup = lpt_setup_backlight,
+       .enable = lpt_enable_backlight,
+       .disable = lpt_disable_backlight,
+       .set = lpt_set_backlight,
+       .get = lpt_get_backlight,
+       .hz_to_pwm = spt_hz_to_pwm,
+};
+
+static const struct intel_panel_bl_funcs pch_pwm_funcs = {
+       .setup = pch_setup_backlight,
+       .enable = pch_enable_backlight,
+       .disable = pch_disable_backlight,
+       .set = pch_set_backlight,
+       .get = pch_get_backlight,
+       .hz_to_pwm = pch_hz_to_pwm,
+};
+
+static const struct intel_panel_bl_funcs ext_pwm_funcs = {
+       .setup = ext_pwm_setup_backlight,
+       .enable = ext_pwm_enable_backlight,
+       .disable = ext_pwm_disable_backlight,
+       .set = ext_pwm_set_backlight,
+       .get = ext_pwm_get_backlight,
+};
+
+static const struct intel_panel_bl_funcs vlv_pwm_funcs = {
+       .setup = vlv_setup_backlight,
+       .enable = vlv_enable_backlight,
+       .disable = vlv_disable_backlight,
+       .set = vlv_set_backlight,
+       .get = vlv_get_backlight,
+       .hz_to_pwm = vlv_hz_to_pwm,
+};
+
+static const struct intel_panel_bl_funcs i965_pwm_funcs = {
+       .setup = i965_setup_backlight,
+       .enable = i965_enable_backlight,
+       .disable = i965_disable_backlight,
+       .set = i9xx_set_backlight,
+       .get = i9xx_get_backlight,
+       .hz_to_pwm = i965_hz_to_pwm,
+};
+
+static const struct intel_panel_bl_funcs i9xx_pwm_funcs = {
+       .setup = i9xx_setup_backlight,
+       .enable = i9xx_enable_backlight,
+       .disable = i9xx_disable_backlight,
+       .set = i9xx_set_backlight,
+       .get = i9xx_get_backlight,
+       .hz_to_pwm = i9xx_hz_to_pwm,
+};
+
+static const struct intel_panel_bl_funcs pwm_bl_funcs = {
+       .setup = intel_pwm_setup_backlight,
+       .enable = intel_pwm_enable_backlight,
+       .disable = intel_pwm_disable_backlight,
+       .set = intel_pwm_set_backlight,
+       .get = intel_pwm_get_backlight,
+};
+
+/* Set up chip specific backlight functions */
+void
+intel_panel_init_backlight_funcs(struct intel_panel *panel)
+{
+       struct intel_connector *connector =
+               container_of(panel, struct intel_connector, panel);
+       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
+
+       if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI &&
+           intel_dsi_dcs_init_backlight_funcs(connector) == 0)
+               return;
+
+       if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv)) {
+               panel->backlight.pwm_funcs = &bxt_pwm_funcs;
+       } else if (INTEL_PCH_TYPE(dev_priv) >= PCH_CNP) {
+               panel->backlight.pwm_funcs = &cnp_pwm_funcs;
+       } else if (INTEL_PCH_TYPE(dev_priv) >= PCH_LPT) {
+               if (HAS_PCH_LPT(dev_priv))
+                       panel->backlight.pwm_funcs = &lpt_pwm_funcs;
+               else
+                       panel->backlight.pwm_funcs = &spt_pwm_funcs;
+       } else if (HAS_PCH_SPLIT(dev_priv)) {
+               panel->backlight.pwm_funcs = &pch_pwm_funcs;
+       } else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
+               if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) {
+                       panel->backlight.pwm_funcs = &ext_pwm_funcs;
+               } else {
+                       panel->backlight.pwm_funcs = &vlv_pwm_funcs;
+               }
+       } else if (DISPLAY_VER(dev_priv) == 4) {
+               panel->backlight.pwm_funcs = &i965_pwm_funcs;
+       } else {
+               panel->backlight.pwm_funcs = &i9xx_pwm_funcs;
+       }
+
+       if (connector->base.connector_type == DRM_MODE_CONNECTOR_eDP &&
+           intel_dp_aux_init_backlight_funcs(connector) == 0)
+               return;
+
+       /* We're using a standard PWM backlight interface */
+       panel->backlight.funcs = &pwm_bl_funcs;
+}
diff --git a/sys/dev/pci/drm/i915/display/intel_backlight.h b/sys/dev/pci/drm/i915/display/intel_backlight.h
new file mode 100644 (file)
index 0000000..282020c
--- /dev/null
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2021 Intel Corporation
+ */
+
+#ifndef __INTEL_BACKLIGHT_H__
+#define __INTEL_BACKLIGHT_H__
+
+#include <linux/types.h>
+
+struct drm_connector;
+struct drm_connector_state;
+struct intel_atomic_state;
+struct intel_connector;
+struct intel_crtc_state;
+struct intel_encoder;
+struct intel_panel;
+enum pipe;
+
+void intel_panel_init_backlight_funcs(struct intel_panel *panel);
+void intel_panel_destroy_backlight(struct intel_panel *panel);
+void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
+                                   u32 level, u32 max);
+int intel_panel_setup_backlight(struct drm_connector *connector,
+                               enum pipe pipe);
+void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
+                                 const struct drm_connector_state *conn_state);
+void intel_panel_update_backlight(struct intel_atomic_state *state,
+                                 struct intel_encoder *encoder,
+                                 const struct intel_crtc_state *crtc_state,
+                                 const struct drm_connector_state *conn_state);
+void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state);
+void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 level);
+u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 level);
+u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 level);
+u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val);
+
+#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
+int intel_backlight_device_register(struct intel_connector *connector);
+void intel_backlight_device_unregister(struct intel_connector *connector);
+#else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
+static inline int intel_backlight_device_register(struct intel_connector *connector)
+{
+       return 0;
+}
+static inline void intel_backlight_device_unregister(struct intel_connector *connector)
+{
+}
+#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
+
+#endif /* __INTEL_BACKLIGHT_H__ */
index 9bed1cc..4f49d78 100644 (file)
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_edid.h>
 
-#include "display/intel_panel.h"
-
 #include "i915_drv.h"
+#include "intel_backlight.h"
 #include "intel_connector.h"
 #include "intel_display_debugfs.h"
 #include "intel_display_types.h"
 #include "intel_hdcp.h"
+#include "intel_panel.h"
 
 int intel_connector_init(struct intel_connector *connector)
 {
index b539515..3c2b80d 100644 (file)
@@ -29,6 +29,7 @@
 
 #include "i915_drv.h"
 #include "intel_audio.h"
+#include "intel_backlight.h"
 #include "intel_combo_phy.h"
 #include "intel_connector.h"
 #include "intel_crtc.h"
@@ -49,7 +50,6 @@
 #include "intel_hdmi.h"
 #include "intel_hotplug.h"
 #include "intel_lspcon.h"
-#include "intel_panel.h"
 #include "intel_pps.h"
 #include "intel_psr.h"
 #include "intel_snps_phy.h"
index 465cb36..74ec212 100644 (file)
@@ -45,6 +45,7 @@
 #include "i915_drv.h"
 #include "intel_atomic.h"
 #include "intel_audio.h"
+#include "intel_backlight.h"
 #include "intel_connector.h"
 #include "intel_ddi.h"
 #include "intel_de.h"
index e7b9086..1380c88 100644 (file)
  * for some reason.
  */
 
+#include <linux/kconfig.h>
+#include "intel_backlight.h"
 #include "intel_display_types.h"
 #include "intel_dp.h"
 #include "intel_dp_aux_backlight.h"
-#include "intel_panel.h"
 
 /* TODO:
  * Implement HDR, right now we just implement the bare minimum to bring us back into SDR mode so we
index e0381b0..8f5741e 100644 (file)
@@ -40,6 +40,7 @@
 
 #include "i915_drv.h"
 #include "intel_atomic.h"
+#include "intel_backlight.h"
 #include "intel_connector.h"
 #include "intel_de.h"
 #include "intel_display_types.h"
index df469af..b7aeb60 100644 (file)
 #include <linux/firmware.h>
 #include <acpi/video.h>
 
-#include "display/intel_panel.h"
-
 #include "i915_drv.h"
 #include "intel_acpi.h"
+#include "intel_backlight.h"
 #include "intel_display_types.h"
 #include "intel_opregion.h"
 
index a99dca7..ad54767 100644 (file)
  *      Chris Wilson <chris@chris-wilson.co.uk>
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
 #include <linux/kernel.h>
-#include <linux/moduleparam.h>
 #include <linux/pwm.h>
 
+#include "intel_backlight.h"
 #include "intel_connector.h"
 #include "intel_de.h"
 #include "intel_display_types.h"
-#include "intel_dp_aux_backlight.h"
-#include "intel_dsi_dcs_backlight.h"
 #include "intel_panel.h"
 
 void
@@ -456,1784 +452,6 @@ out:
        return 0;
 }
 
-/**
- * scale - scale values from one range to another
- * @source_val: value in range [@source_min..@source_max]
- * @source_min: minimum legal value for @source_val
- * @source_max: maximum legal value for @source_val
- * @target_min: corresponding target value for @source_min
- * @target_max: corresponding target value for @source_max
- *
- * Return @source_val in range [@source_min..@source_max] scaled to range
- * [@target_min..@target_max].
- */
-static u32 scale(u32 source_val,
-                u32 source_min, u32 source_max,
-                u32 target_min, u32 target_max)
-{
-       u64 target_val;
-
-       WARN_ON(source_min > source_max);
-       WARN_ON(target_min > target_max);
-
-       /* defensive */
-       source_val = clamp(source_val, source_min, source_max);
-
-       /* avoid overflows */
-       target_val = mul_u32_u32(source_val - source_min,
-                                target_max - target_min);
-       target_val = DIV_ROUND_CLOSEST_ULL(target_val, source_max - source_min);
-       target_val += target_min;
-
-       return target_val;
-}
-
-/* Scale user_level in range [0..user_max] to [0..hw_max], clamping the result
- * to [hw_min..hw_max]. */
-static u32 clamp_user_to_hw(struct intel_connector *connector,
-                           u32 user_level, u32 user_max)
-{
-       struct intel_panel *panel = &connector->panel;
-       u32 hw_level;
-
-       hw_level = scale(user_level, 0, user_max, 0, panel->backlight.max);
-       hw_level = clamp(hw_level, panel->backlight.min, panel->backlight.max);
-
-       return hw_level;
-}
-
-/* Scale hw_level in range [hw_min..hw_max] to [0..user_max]. */
-static u32 scale_hw_to_user(struct intel_connector *connector,
-                           u32 hw_level, u32 user_max)
-{
-       struct intel_panel *panel = &connector->panel;
-
-       return scale(hw_level, panel->backlight.min, panel->backlight.max,
-                    0, user_max);
-}
-
-u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 val)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
-
-       if (dev_priv->params.invert_brightness < 0)
-               return val;
-
-       if (dev_priv->params.invert_brightness > 0 ||
-           dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS) {
-               return panel->backlight.pwm_level_max - val + panel->backlight.pwm_level_min;
-       }
-
-       return val;
-}
-
-void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 val)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *i915 = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       drm_dbg_kms(&i915->drm, "set backlight PWM = %d\n", val);
-       panel->backlight.pwm_funcs->set(conn_state, val);
-}
-
-u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 val)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       drm_WARN_ON_ONCE(&dev_priv->drm,
-                        panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
-
-       val = scale(val, panel->backlight.min, panel->backlight.max,
-                   panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
-
-       return intel_panel_invert_pwm_level(connector, val);
-}
-
-u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       drm_WARN_ON_ONCE(&dev_priv->drm,
-                        panel->backlight.max == 0 || panel->backlight.pwm_level_max == 0);
-
-       if (dev_priv->params.invert_brightness > 0 ||
-           (dev_priv->params.invert_brightness == 0 && dev_priv->quirks & QUIRK_INVERT_BRIGHTNESS))
-               val = panel->backlight.pwm_level_max - (val - panel->backlight.pwm_level_min);
-
-       return scale(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max,
-                    panel->backlight.min, panel->backlight.max);
-}
-
-static u32 lpt_get_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-
-       return intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & BACKLIGHT_DUTY_CYCLE_MASK;
-}
-
-static u32 pch_get_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-
-       return intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
-}
-
-static u32 i9xx_get_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 val;
-
-       val = intel_de_read(dev_priv, BLC_PWM_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
-       if (DISPLAY_VER(dev_priv) < 4)
-               val >>= 1;
-
-       if (panel->backlight.combination_mode) {
-               u8 lbpc;
-
-               pci_read_config_byte(dev_priv->drm.pdev, LBPC, &lbpc);
-               val *= lbpc;
-       }
-
-       return val;
-}
-
-static u32 vlv_get_backlight(struct intel_connector *connector, enum pipe pipe)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-
-       if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
-               return 0;
-
-       return intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & BACKLIGHT_DUTY_CYCLE_MASK;
-}
-
-static u32 bxt_get_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       return intel_de_read(dev_priv,
-                            BXT_BLC_PWM_DUTY(panel->backlight.controller));
-}
-
-static u32 ext_pwm_get_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       STUB();
-       return 0;
-#ifdef notyet
-       struct intel_panel *panel = &connector->panel;
-       struct pwm_state state;
-
-       pwm_get_state(panel->backlight.pwm, &state);
-       return pwm_get_relative_duty_cycle(&state, 100);
-#endif
-}
-
-static void lpt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-
-       u32 val = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2) & ~BACKLIGHT_DUTY_CYCLE_MASK;
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, val | level);
-}
-
-static void pch_set_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       u32 tmp;
-
-       tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL) & ~BACKLIGHT_DUTY_CYCLE_MASK;
-       intel_de_write(dev_priv, BLC_PWM_CPU_CTL, tmp | level);
-}
-
-static void i9xx_set_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 tmp, mask;
-
-       drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
-
-       if (panel->backlight.combination_mode) {
-               u8 lbpc;
-
-               lbpc = level * 0xfe / panel->backlight.pwm_level_max + 1;
-               level /= lbpc;
-               pci_write_config_byte(dev_priv->drm.pdev, LBPC, lbpc);
-       }
-
-       if (DISPLAY_VER(dev_priv) == 4) {
-               mask = BACKLIGHT_DUTY_CYCLE_MASK;
-       } else {
-               level <<= 1;
-               mask = BACKLIGHT_DUTY_CYCLE_MASK_PNV;
-       }
-
-       tmp = intel_de_read(dev_priv, BLC_PWM_CTL) & ~mask;
-       intel_de_write(dev_priv, BLC_PWM_CTL, tmp | level);
-}
-
-static void vlv_set_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
-       u32 tmp;
-
-       tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe)) & ~BACKLIGHT_DUTY_CYCLE_MASK;
-       intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), tmp | level);
-}
-
-static void bxt_set_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       intel_de_write(dev_priv,
-                      BXT_BLC_PWM_DUTY(panel->backlight.controller), level);
-}
-
-static void ext_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       STUB();
-#ifdef notyet
-       struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
-
-       pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
-       pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
-#endif
-}
-
-static void
-intel_panel_actually_set_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *i915 = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       drm_dbg_kms(&i915->drm, "set backlight level = %d\n", level);
-
-       panel->backlight.funcs->set(conn_state, level);
-}
-
-/* set backlight brightness to level in range [0..max], assuming hw min is
- * respected.
- */
-void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
-                                   u32 user_level, u32 user_max)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 hw_level;
-
-       /*
-        * Lack of crtc may occur during driver init because
-        * connection_mutex isn't held across the entire backlight
-        * setup + modeset readout, and the BIOS can issue the
-        * requests at any time.
-        */
-       if (!panel->backlight.present || !conn_state->crtc)
-               return;
-
-       mutex_lock(&dev_priv->backlight_lock);
-
-       drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
-
-       hw_level = clamp_user_to_hw(connector, user_level, user_max);
-       panel->backlight.level = hw_level;
-
-       if (panel->backlight.device)
-               panel->backlight.device->props.brightness =
-                       scale_hw_to_user(connector,
-                                        panel->backlight.level,
-                                        panel->backlight.device->props.max_brightness);
-
-       if (panel->backlight.enabled)
-               intel_panel_actually_set_backlight(conn_state, hw_level);
-
-       mutex_unlock(&dev_priv->backlight_lock);
-}
-
-static void lpt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       u32 tmp;
-
-       intel_panel_set_pwm_level(old_conn_state, level);
-
-       /*
-        * Although we don't support or enable CPU PWM with LPT/SPT based
-        * systems, it may have been enabled prior to loading the
-        * driver. Disable to avoid warnings on LCPLL disable.
-        *
-        * This needs rework if we need to add support for CPU PWM on PCH split
-        * platforms.
-        */
-       tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
-       if (tmp & BLM_PWM_ENABLE) {
-               drm_dbg_kms(&dev_priv->drm,
-                           "cpu backlight was enabled, disabling\n");
-               intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
-                              tmp & ~BLM_PWM_ENABLE);
-       }
-
-       tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
-}
-
-static void pch_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
-{
-       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       u32 tmp;
-
-       intel_panel_set_pwm_level(old_conn_state, val);
-
-       tmp = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
-       intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, tmp & ~BLM_PWM_ENABLE);
-
-       tmp = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, tmp & ~BLM_PCH_PWM_ENABLE);
-}
-
-static void i9xx_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
-{
-       intel_panel_set_pwm_level(old_conn_state, val);
-}
-
-static void i965_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
-{
-       struct drm_i915_private *dev_priv = to_i915(old_conn_state->connector->dev);
-       u32 tmp;
-
-       intel_panel_set_pwm_level(old_conn_state, val);
-
-       tmp = intel_de_read(dev_priv, BLC_PWM_CTL2);
-       intel_de_write(dev_priv, BLC_PWM_CTL2, tmp & ~BLM_PWM_ENABLE);
-}
-
-static void vlv_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
-{
-       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       enum pipe pipe = to_intel_crtc(old_conn_state->crtc)->pipe;
-       u32 tmp;
-
-       intel_panel_set_pwm_level(old_conn_state, val);
-
-       tmp = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
-       intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
-                      tmp & ~BLM_PWM_ENABLE);
-}
-
-static void bxt_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
-{
-       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 tmp;
-
-       intel_panel_set_pwm_level(old_conn_state, val);
-
-       tmp = intel_de_read(dev_priv,
-                           BXT_BLC_PWM_CTL(panel->backlight.controller));
-       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
-                      tmp & ~BXT_BLC_PWM_ENABLE);
-
-       if (panel->backlight.controller == 1) {
-               val = intel_de_read(dev_priv, UTIL_PIN_CTL);
-               val &= ~UTIL_PIN_ENABLE;
-               intel_de_write(dev_priv, UTIL_PIN_CTL, val);
-       }
-}
-
-static void cnp_disable_backlight(const struct drm_connector_state *old_conn_state, u32 val)
-{
-       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 tmp;
-
-       intel_panel_set_pwm_level(old_conn_state, val);
-
-       tmp = intel_de_read(dev_priv,
-                           BXT_BLC_PWM_CTL(panel->backlight.controller));
-       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
-                      tmp & ~BXT_BLC_PWM_ENABLE);
-}
-
-static void ext_pwm_disable_backlight(const struct drm_connector_state *old_conn_state, u32 level)
-{
-       STUB();
-#ifdef notyet
-       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
-       struct intel_panel *panel = &connector->panel;
-
-       panel->backlight.pwm_state.enabled = false;
-       pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
-#endif
-}
-
-void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state)
-{
-       struct intel_connector *connector = to_intel_connector(old_conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       if (!panel->backlight.present)
-               return;
-
-       /*
-        * Do not disable backlight on the vga_switcheroo path. When switching
-        * away from i915, the other client may depend on i915 to handle the
-        * backlight. This will leave the backlight on unnecessarily when
-        * another client is not activated.
-        */
-       if (dev_priv->drm.switch_power_state == DRM_SWITCH_POWER_CHANGING) {
-               drm_dbg_kms(&dev_priv->drm,
-                           "Skipping backlight disable on vga switch\n");
-               return;
-       }
-
-       mutex_lock(&dev_priv->backlight_lock);
-
-       if (panel->backlight.device)
-               panel->backlight.device->props.power = FB_BLANK_POWERDOWN;
-       panel->backlight.enabled = false;
-       panel->backlight.funcs->disable(old_conn_state, 0);
-
-       mutex_unlock(&dev_priv->backlight_lock);
-}
-
-static void lpt_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 pch_ctl1, pch_ctl2, schicken;
-
-       pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
-       if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
-               drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
-               pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
-               intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
-       }
-
-       if (HAS_PCH_LPT(dev_priv)) {
-               schicken = intel_de_read(dev_priv, SOUTH_CHICKEN2);
-               if (panel->backlight.alternate_pwm_increment)
-                       schicken |= LPT_PWM_GRANULARITY;
-               else
-                       schicken &= ~LPT_PWM_GRANULARITY;
-               intel_de_write(dev_priv, SOUTH_CHICKEN2, schicken);
-       } else {
-               schicken = intel_de_read(dev_priv, SOUTH_CHICKEN1);
-               if (panel->backlight.alternate_pwm_increment)
-                       schicken |= SPT_PWM_GRANULARITY;
-               else
-                       schicken &= ~SPT_PWM_GRANULARITY;
-               intel_de_write(dev_priv, SOUTH_CHICKEN1, schicken);
-       }
-
-       pch_ctl2 = panel->backlight.pwm_level_max << 16;
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
-
-       pch_ctl1 = 0;
-       if (panel->backlight.active_low_pwm)
-               pch_ctl1 |= BLM_PCH_POLARITY;
-
-       /* After LPT, override is the default. */
-       if (HAS_PCH_LPT(dev_priv))
-               pch_ctl1 |= BLM_PCH_OVERRIDE_ENABLE;
-
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
-       intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
-                      pch_ctl1 | BLM_PCH_PWM_ENABLE);
-
-       /* This won't stick until the above enable. */
-       intel_panel_set_pwm_level(conn_state, level);
-}
-
-static void pch_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
-       u32 cpu_ctl2, pch_ctl1, pch_ctl2;
-
-       cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
-       if (cpu_ctl2 & BLM_PWM_ENABLE) {
-               drm_dbg_kms(&dev_priv->drm, "cpu backlight already enabled\n");
-               cpu_ctl2 &= ~BLM_PWM_ENABLE;
-               intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
-       }
-
-       pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
-       if (pch_ctl1 & BLM_PCH_PWM_ENABLE) {
-               drm_dbg_kms(&dev_priv->drm, "pch backlight already enabled\n");
-               pch_ctl1 &= ~BLM_PCH_PWM_ENABLE;
-               intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
-       }
-
-       if (cpu_transcoder == TRANSCODER_EDP)
-               cpu_ctl2 = BLM_TRANSCODER_EDP;
-       else
-               cpu_ctl2 = BLM_PIPE(cpu_transcoder);
-       intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2);
-       intel_de_posting_read(dev_priv, BLC_PWM_CPU_CTL2);
-       intel_de_write(dev_priv, BLC_PWM_CPU_CTL2, cpu_ctl2 | BLM_PWM_ENABLE);
-
-       /* This won't stick until the above enable. */
-       intel_panel_set_pwm_level(conn_state, level);
-
-       pch_ctl2 = panel->backlight.pwm_level_max << 16;
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL2, pch_ctl2);
-
-       pch_ctl1 = 0;
-       if (panel->backlight.active_low_pwm)
-               pch_ctl1 |= BLM_PCH_POLARITY;
-
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1, pch_ctl1);
-       intel_de_posting_read(dev_priv, BLC_PWM_PCH_CTL1);
-       intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
-                      pch_ctl1 | BLM_PCH_PWM_ENABLE);
-}
-
-static void i9xx_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                 const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 ctl, freq;
-
-       ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
-       if (ctl & BACKLIGHT_DUTY_CYCLE_MASK_PNV) {
-               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
-               intel_de_write(dev_priv, BLC_PWM_CTL, 0);
-       }
-
-       freq = panel->backlight.pwm_level_max;
-       if (panel->backlight.combination_mode)
-               freq /= 0xff;
-
-       ctl = freq << 17;
-       if (panel->backlight.combination_mode)
-               ctl |= BLM_LEGACY_MODE;
-       if (IS_PINEVIEW(dev_priv) && panel->backlight.active_low_pwm)
-               ctl |= BLM_POLARITY_PNV;
-
-       intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
-       intel_de_posting_read(dev_priv, BLC_PWM_CTL);
-
-       /* XXX: combine this into above write? */
-       intel_panel_set_pwm_level(conn_state, level);
-
-       /*
-        * Needed to enable backlight on some 855gm models. BLC_HIST_CTL is
-        * 855gm only, but checking for gen2 is safe, as 855gm is the only gen2
-        * that has backlight.
-        */
-       if (DISPLAY_VER(dev_priv) == 2)
-               intel_de_write(dev_priv, BLC_HIST_CTL, BLM_HISTOGRAM_ENABLE);
-}
-
-static void i965_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                 const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       enum pipe pipe = to_intel_crtc(conn_state->crtc)->pipe;
-       u32 ctl, ctl2, freq;
-
-       ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
-       if (ctl2 & BLM_PWM_ENABLE) {
-               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
-               ctl2 &= ~BLM_PWM_ENABLE;
-               intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
-       }
-
-       freq = panel->backlight.pwm_level_max;
-       if (panel->backlight.combination_mode)
-               freq /= 0xff;
-
-       ctl = freq << 16;
-       intel_de_write(dev_priv, BLC_PWM_CTL, ctl);
-
-       ctl2 = BLM_PIPE(pipe);
-       if (panel->backlight.combination_mode)
-               ctl2 |= BLM_COMBINATION_MODE;
-       if (panel->backlight.active_low_pwm)
-               ctl2 |= BLM_POLARITY_I965;
-       intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2);
-       intel_de_posting_read(dev_priv, BLC_PWM_CTL2);
-       intel_de_write(dev_priv, BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
-
-       intel_panel_set_pwm_level(conn_state, level);
-}
-
-static void vlv_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
-       u32 ctl, ctl2;
-
-       ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
-       if (ctl2 & BLM_PWM_ENABLE) {
-               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
-               ctl2 &= ~BLM_PWM_ENABLE;
-               intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
-       }
-
-       ctl = panel->backlight.pwm_level_max << 16;
-       intel_de_write(dev_priv, VLV_BLC_PWM_CTL(pipe), ctl);
-
-       /* XXX: combine this into above write? */
-       intel_panel_set_pwm_level(conn_state, level);
-
-       ctl2 = 0;
-       if (panel->backlight.active_low_pwm)
-               ctl2 |= BLM_POLARITY_I965;
-       intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe), ctl2);
-       intel_de_posting_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
-       intel_de_write(dev_priv, VLV_BLC_PWM_CTL2(pipe),
-                      ctl2 | BLM_PWM_ENABLE);
-}
-
-static void bxt_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
-       u32 pwm_ctl, val;
-
-       /* Controller 1 uses the utility pin. */
-       if (panel->backlight.controller == 1) {
-               val = intel_de_read(dev_priv, UTIL_PIN_CTL);
-               if (val & UTIL_PIN_ENABLE) {
-                       drm_dbg_kms(&dev_priv->drm,
-                                   "util pin already enabled\n");
-                       val &= ~UTIL_PIN_ENABLE;
-                       intel_de_write(dev_priv, UTIL_PIN_CTL, val);
-               }
-
-               val = 0;
-               if (panel->backlight.util_pin_active_low)
-                       val |= UTIL_PIN_POLARITY;
-               intel_de_write(dev_priv, UTIL_PIN_CTL,
-                              val | UTIL_PIN_PIPE(pipe) | UTIL_PIN_MODE_PWM | UTIL_PIN_ENABLE);
-       }
-
-       pwm_ctl = intel_de_read(dev_priv,
-                               BXT_BLC_PWM_CTL(panel->backlight.controller));
-       if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
-               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
-               pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
-               intel_de_write(dev_priv,
-                              BXT_BLC_PWM_CTL(panel->backlight.controller),
-                              pwm_ctl);
-       }
-
-       intel_de_write(dev_priv,
-                      BXT_BLC_PWM_FREQ(panel->backlight.controller),
-                      panel->backlight.pwm_level_max);
-
-       intel_panel_set_pwm_level(conn_state, level);
-
-       pwm_ctl = 0;
-       if (panel->backlight.active_low_pwm)
-               pwm_ctl |= BXT_BLC_PWM_POLARITY;
-
-       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
-                      pwm_ctl);
-       intel_de_posting_read(dev_priv,
-                             BXT_BLC_PWM_CTL(panel->backlight.controller));
-       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
-                      pwm_ctl | BXT_BLC_PWM_ENABLE);
-}
-
-static void cnp_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 pwm_ctl;
-
-       pwm_ctl = intel_de_read(dev_priv,
-                               BXT_BLC_PWM_CTL(panel->backlight.controller));
-       if (pwm_ctl & BXT_BLC_PWM_ENABLE) {
-               drm_dbg_kms(&dev_priv->drm, "backlight already enabled\n");
-               pwm_ctl &= ~BXT_BLC_PWM_ENABLE;
-               intel_de_write(dev_priv,
-                              BXT_BLC_PWM_CTL(panel->backlight.controller),
-                              pwm_ctl);
-       }
-
-       intel_de_write(dev_priv,
-                      BXT_BLC_PWM_FREQ(panel->backlight.controller),
-                      panel->backlight.pwm_level_max);
-
-       intel_panel_set_pwm_level(conn_state, level);
-
-       pwm_ctl = 0;
-       if (panel->backlight.active_low_pwm)
-               pwm_ctl |= BXT_BLC_PWM_POLARITY;
-
-       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
-                      pwm_ctl);
-       intel_de_posting_read(dev_priv,
-                             BXT_BLC_PWM_CTL(panel->backlight.controller));
-       intel_de_write(dev_priv, BXT_BLC_PWM_CTL(panel->backlight.controller),
-                      pwm_ctl | BXT_BLC_PWM_ENABLE);
-}
-
-static void ext_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                    const struct drm_connector_state *conn_state, u32 level)
-{
-       STUB();
-#ifdef notyet
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct intel_panel *panel = &connector->panel;
-
-       pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
-       panel->backlight.pwm_state.enabled = true;
-       pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
-#endif
-}
-
-static void __intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                          const struct drm_connector_state *conn_state)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct intel_panel *panel = &connector->panel;
-
-       WARN_ON(panel->backlight.max == 0);
-
-       if (panel->backlight.level <= panel->backlight.min) {
-               panel->backlight.level = panel->backlight.max;
-               if (panel->backlight.device)
-                       panel->backlight.device->props.brightness =
-                               scale_hw_to_user(connector,
-                                                panel->backlight.level,
-                                                panel->backlight.device->props.max_brightness);
-       }
-
-       panel->backlight.funcs->enable(crtc_state, conn_state, panel->backlight.level);
-       panel->backlight.enabled = true;
-       if (panel->backlight.device)
-               panel->backlight.device->props.power = FB_BLANK_UNBLANK;
-}
-
-void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                 const struct drm_connector_state *conn_state)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       enum pipe pipe = to_intel_crtc(crtc_state->uapi.crtc)->pipe;
-
-       if (!panel->backlight.present)
-               return;
-
-       drm_dbg_kms(&dev_priv->drm, "pipe %c\n", pipe_name(pipe));
-
-       mutex_lock(&dev_priv->backlight_lock);
-
-       __intel_panel_enable_backlight(crtc_state, conn_state);
-
-       mutex_unlock(&dev_priv->backlight_lock);
-}
-
-#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
-static u32 intel_panel_get_backlight(struct intel_connector *connector)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 val = 0;
-
-       mutex_lock(&dev_priv->backlight_lock);
-
-       if (panel->backlight.enabled)
-               val = panel->backlight.funcs->get(connector, intel_connector_get_pipe(connector));
-
-       mutex_unlock(&dev_priv->backlight_lock);
-
-       drm_dbg_kms(&dev_priv->drm, "get backlight PWM = %d\n", val);
-       return val;
-}
-
-/* Scale user_level in range [0..user_max] to [hw_min..hw_max]. */
-static u32 scale_user_to_hw(struct intel_connector *connector,
-                           u32 user_level, u32 user_max)
-{
-       struct intel_panel *panel = &connector->panel;
-
-       return scale(user_level, 0, user_max,
-                    panel->backlight.min, panel->backlight.max);
-}
-
-/* set backlight brightness to level in range [0..max], scaling wrt hw min */
-static void intel_panel_set_backlight(const struct drm_connector_state *conn_state,
-                                     u32 user_level, u32 user_max)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 hw_level;
-
-       if (!panel->backlight.present)
-               return;
-
-       mutex_lock(&dev_priv->backlight_lock);
-
-       drm_WARN_ON(&dev_priv->drm, panel->backlight.max == 0);
-
-       hw_level = scale_user_to_hw(connector, user_level, user_max);
-       panel->backlight.level = hw_level;
-
-       if (panel->backlight.enabled)
-               intel_panel_actually_set_backlight(conn_state, hw_level);
-
-       mutex_unlock(&dev_priv->backlight_lock);
-}
-
-static int intel_backlight_device_update_status(struct backlight_device *bd)
-{
-       struct intel_connector *connector = bl_get_data(bd);
-       struct intel_panel *panel = &connector->panel;
-       struct drm_device *dev = connector->base.dev;
-
-       drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
-       DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
-                     bd->props.brightness, bd->props.max_brightness);
-       intel_panel_set_backlight(connector->base.state, bd->props.brightness,
-                                 bd->props.max_brightness);
-
-       /*
-        * Allow flipping bl_power as a sub-state of enabled. Sadly the
-        * backlight class device does not make it easy to to differentiate
-        * between callbacks for brightness and bl_power, so our backlight_power
-        * callback needs to take this into account.
-        */
-       if (panel->backlight.enabled) {
-               if (panel->backlight.power) {
-                       bool enable = bd->props.power == FB_BLANK_UNBLANK &&
-                               bd->props.brightness != 0;
-                       panel->backlight.power(connector, enable);
-               }
-       } else {
-               bd->props.power = FB_BLANK_POWERDOWN;
-       }
-
-       drm_modeset_unlock(&dev->mode_config.connection_mutex);
-       return 0;
-}
-
-static int intel_backlight_device_get_brightness(struct backlight_device *bd)
-{
-       struct intel_connector *connector = bl_get_data(bd);
-       struct drm_device *dev = connector->base.dev;
-       struct drm_i915_private *dev_priv = to_i915(dev);
-       intel_wakeref_t wakeref;
-       int ret = 0;
-
-       with_intel_runtime_pm(&dev_priv->runtime_pm, wakeref) {
-               u32 hw_level;
-
-               drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
-
-               hw_level = intel_panel_get_backlight(connector);
-               ret = scale_hw_to_user(connector,
-                                      hw_level, bd->props.max_brightness);
-
-               drm_modeset_unlock(&dev->mode_config.connection_mutex);
-       }
-
-       return ret;
-}
-
-static const struct backlight_ops intel_backlight_device_ops = {
-       .update_status = intel_backlight_device_update_status,
-       .get_brightness = intel_backlight_device_get_brightness,
-};
-
-int intel_backlight_device_register(struct intel_connector *connector)
-{
-       struct drm_i915_private *i915 = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       struct backlight_properties props;
-       struct backlight_device *bd;
-       const char *name;
-       int ret = 0;
-
-       if (WARN_ON(panel->backlight.device))
-               return -ENODEV;
-
-       if (!panel->backlight.present)
-               return 0;
-
-       WARN_ON(panel->backlight.max == 0);
-
-       memset(&props, 0, sizeof(props));
-       props.type = BACKLIGHT_RAW;
-
-       /*
-        * Note: Everything should work even if the backlight device max
-        * presented to the userspace is arbitrarily chosen.
-        */
-       props.max_brightness = panel->backlight.max;
-       props.brightness = scale_hw_to_user(connector,
-                                           panel->backlight.level,
-                                           props.max_brightness);
-
-       if (panel->backlight.enabled)
-               props.power = FB_BLANK_UNBLANK;
-       else
-               props.power = FB_BLANK_POWERDOWN;
-
-       name = kstrdup("intel_backlight", GFP_KERNEL);
-       if (!name)
-               return -ENOMEM;
-
-       bd = backlight_device_register(name, connector->base.kdev, connector,
-                                      &intel_backlight_device_ops, &props);
-
-       /*
-        * Using the same name independent of the drm device or connector
-        * prevents registration of multiple backlight devices in the
-        * driver. However, we need to use the default name for backward
-        * compatibility. Use unique names for subsequent backlight devices as a
-        * fallback when the default name already exists.
-        */
-       if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) {
-               kfree(name);
-               name = kasprintf(GFP_KERNEL, "card%d-%s-backlight",
-                                i915->drm.primary->index, connector->base.name);
-               if (!name)
-                       return -ENOMEM;
-
-               bd = backlight_device_register(name, connector->base.kdev, connector,
-                                              &intel_backlight_device_ops, &props);
-       }
-
-       if (IS_ERR(bd)) {
-               drm_err(&i915->drm,
-                       "[CONNECTOR:%d:%s] backlight device %s register failed: %ld\n",
-                       connector->base.base.id, connector->base.name, name, PTR_ERR(bd));
-               ret = PTR_ERR(bd);
-               goto out;
-       }
-
-       panel->backlight.device = bd;
-
-       drm_dbg_kms(&i915->drm,
-                   "[CONNECTOR:%d:%s] backlight device %s registered\n",
-                   connector->base.base.id, connector->base.name, name);
-
-out:
-       kfree(name);
-
-       return ret;
-}
-
-void intel_backlight_device_unregister(struct intel_connector *connector)
-{
-       struct intel_panel *panel = &connector->panel;
-
-       if (panel->backlight.device) {
-               backlight_device_unregister(panel->backlight.device);
-               panel->backlight.device = NULL;
-       }
-}
-#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
-
-/*
- * CNP: PWM clock frequency is 19.2 MHz or 24 MHz.
- *      PWM increment = 1
- */
-static u32 cnp_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-
-       return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
-                                pwm_freq_hz);
-}
-
-/*
- * BXT: PWM clock frequency = 19.2 MHz.
- */
-static u32 bxt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
-{
-       return DIV_ROUND_CLOSEST(KHz(19200), pwm_freq_hz);
-}
-
-/*
- * SPT: This value represents the period of the PWM stream in clock periods
- * multiplied by 16 (default increment) or 128 (alternate increment selected in
- * SCHICKEN_1 bit 0). PWM clock is 24 MHz.
- */
-static u32 spt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
-{
-       struct intel_panel *panel = &connector->panel;
-       u32 mul;
-
-       if (panel->backlight.alternate_pwm_increment)
-               mul = 128;
-       else
-               mul = 16;
-
-       return DIV_ROUND_CLOSEST(MHz(24), pwm_freq_hz * mul);
-}
-
-/*
- * LPT: This value represents the period of the PWM stream in clock periods
- * multiplied by 128 (default increment) or 16 (alternate increment, selected in
- * LPT SOUTH_CHICKEN2 register bit 5).
- */
-static u32 lpt_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 mul, clock;
-
-       if (panel->backlight.alternate_pwm_increment)
-               mul = 16;
-       else
-               mul = 128;
-
-       if (HAS_PCH_LPT_H(dev_priv))
-               clock = MHz(135); /* LPT:H */
-       else
-               clock = MHz(24); /* LPT:LP */
-
-       return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
-}
-
-/*
- * ILK/SNB/IVB: This value represents the period of the PWM stream in PCH
- * display raw clocks multiplied by 128.
- */
-static u32 pch_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-
-       return DIV_ROUND_CLOSEST(KHz(RUNTIME_INFO(dev_priv)->rawclk_freq),
-                                pwm_freq_hz * 128);
-}
-
-/*
- * Gen2: This field determines the number of time base events (display core
- * clock frequency/32) in total for a complete cycle of modulated backlight
- * control.
- *
- * Gen3: A time base event equals the display core clock ([DevPNV] HRAW clock)
- * divided by 32.
- */
-static u32 i9xx_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       int clock;
-
-       if (IS_PINEVIEW(dev_priv))
-               clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
-       else
-               clock = KHz(dev_priv->cdclk.hw.cdclk);
-
-       return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 32);
-}
-
-/*
- * Gen4: This value represents the period of the PWM stream in display core
- * clocks ([DevCTG] HRAW clocks) multiplied by 128.
- *
- */
-static u32 i965_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       int clock;
-
-       if (IS_G4X(dev_priv))
-               clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
-       else
-               clock = KHz(dev_priv->cdclk.hw.cdclk);
-
-       return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * 128);
-}
-
-/*
- * VLV: This value represents the period of the PWM stream in display core
- * clocks ([DevCTG] 200MHz HRAW clocks) multiplied by 128 or 25MHz S0IX clocks
- * multiplied by 16. CHV uses a 19.2MHz S0IX clock.
- */
-static u32 vlv_hz_to_pwm(struct intel_connector *connector, u32 pwm_freq_hz)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       int mul, clock;
-
-       if ((intel_de_read(dev_priv, CBR1_VLV) & CBR_PWM_CLOCK_MUX_SELECT) == 0) {
-               if (IS_CHERRYVIEW(dev_priv))
-                       clock = KHz(19200);
-               else
-                       clock = MHz(25);
-               mul = 16;
-       } else {
-               clock = KHz(RUNTIME_INFO(dev_priv)->rawclk_freq);
-               mul = 128;
-       }
-
-       return DIV_ROUND_CLOSEST(clock, pwm_freq_hz * mul);
-}
-
-static u16 get_vbt_pwm_freq(struct drm_i915_private *dev_priv)
-{
-       u16 pwm_freq_hz = dev_priv->vbt.backlight.pwm_freq_hz;
-
-       if (pwm_freq_hz) {
-               drm_dbg_kms(&dev_priv->drm,
-                           "VBT defined backlight frequency %u Hz\n",
-                           pwm_freq_hz);
-       } else {
-               pwm_freq_hz = 200;
-               drm_dbg_kms(&dev_priv->drm,
-                           "default backlight frequency %u Hz\n",
-                           pwm_freq_hz);
-       }
-
-       return pwm_freq_hz;
-}
-
-static u32 get_backlight_max_vbt(struct intel_connector *connector)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u16 pwm_freq_hz = get_vbt_pwm_freq(dev_priv);
-       u32 pwm;
-
-       if (!panel->backlight.pwm_funcs->hz_to_pwm) {
-               drm_dbg_kms(&dev_priv->drm,
-                           "backlight frequency conversion not supported\n");
-               return 0;
-       }
-
-       pwm = panel->backlight.pwm_funcs->hz_to_pwm(connector, pwm_freq_hz);
-       if (!pwm) {
-               drm_dbg_kms(&dev_priv->drm,
-                           "backlight frequency conversion failed\n");
-               return 0;
-       }
-
-       return pwm;
-}
-
-/*
- * Note: The setup hooks can't assume pipe is set!
- */
-static u32 get_backlight_min_vbt(struct intel_connector *connector)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       int min;
-
-       drm_WARN_ON(&dev_priv->drm, panel->backlight.pwm_level_max == 0);
-
-       /*
-        * XXX: If the vbt value is 255, it makes min equal to max, which leads
-        * to problems. There are such machines out there. Either our
-        * interpretation is wrong or the vbt has bogus data. Or both. Safeguard
-        * against this by letting the minimum be at most (arbitrarily chosen)
-        * 25% of the max.
-        */
-       min = clamp_t(int, dev_priv->vbt.backlight.min_brightness, 0, 64);
-       if (min != dev_priv->vbt.backlight.min_brightness) {
-               drm_dbg_kms(&dev_priv->drm,
-                           "clamping VBT min backlight %d/255 to %d/255\n",
-                           dev_priv->vbt.backlight.min_brightness, min);
-       }
-
-       /* vbt value is a coefficient in range [0..255] */
-       return scale(min, 0, 255, 0, panel->backlight.pwm_level_max);
-}
-
-static int lpt_setup_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 cpu_ctl2, pch_ctl1, pch_ctl2, val;
-       bool alt, cpu_mode;
-
-       if (HAS_PCH_LPT(dev_priv))
-               alt = intel_de_read(dev_priv, SOUTH_CHICKEN2) & LPT_PWM_GRANULARITY;
-       else
-               alt = intel_de_read(dev_priv, SOUTH_CHICKEN1) & SPT_PWM_GRANULARITY;
-       panel->backlight.alternate_pwm_increment = alt;
-
-       pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
-       panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
-
-       pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
-       panel->backlight.pwm_level_max = pch_ctl2 >> 16;
-
-       cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
-
-       if (!panel->backlight.pwm_level_max)
-               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
-
-       if (!panel->backlight.pwm_level_max)
-               return -ENODEV;
-
-       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
-
-       panel->backlight.pwm_enabled = pch_ctl1 & BLM_PCH_PWM_ENABLE;
-
-       cpu_mode = panel->backlight.pwm_enabled && HAS_PCH_LPT(dev_priv) &&
-                  !(pch_ctl1 & BLM_PCH_OVERRIDE_ENABLE) &&
-                  (cpu_ctl2 & BLM_PWM_ENABLE);
-
-       if (cpu_mode) {
-               val = pch_get_backlight(connector, unused);
-
-               drm_dbg_kms(&dev_priv->drm,
-                           "CPU backlight register was enabled, switching to PCH override\n");
-
-               /* Write converted CPU PWM value to PCH override register */
-               lpt_set_backlight(connector->base.state, val);
-               intel_de_write(dev_priv, BLC_PWM_PCH_CTL1,
-                              pch_ctl1 | BLM_PCH_OVERRIDE_ENABLE);
-
-               intel_de_write(dev_priv, BLC_PWM_CPU_CTL2,
-                              cpu_ctl2 & ~BLM_PWM_ENABLE);
-       }
-
-       return 0;
-}
-
-static int pch_setup_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 cpu_ctl2, pch_ctl1, pch_ctl2;
-
-       pch_ctl1 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL1);
-       panel->backlight.active_low_pwm = pch_ctl1 & BLM_PCH_POLARITY;
-
-       pch_ctl2 = intel_de_read(dev_priv, BLC_PWM_PCH_CTL2);
-       panel->backlight.pwm_level_max = pch_ctl2 >> 16;
-
-       if (!panel->backlight.pwm_level_max)
-               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
-
-       if (!panel->backlight.pwm_level_max)
-               return -ENODEV;
-
-       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
-
-       cpu_ctl2 = intel_de_read(dev_priv, BLC_PWM_CPU_CTL2);
-       panel->backlight.pwm_enabled = (cpu_ctl2 & BLM_PWM_ENABLE) &&
-               (pch_ctl1 & BLM_PCH_PWM_ENABLE);
-
-       return 0;
-}
-
-static int i9xx_setup_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 ctl, val;
-
-       ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
-
-       if (DISPLAY_VER(dev_priv) == 2 || IS_I915GM(dev_priv) || IS_I945GM(dev_priv))
-               panel->backlight.combination_mode = ctl & BLM_LEGACY_MODE;
-
-       if (IS_PINEVIEW(dev_priv))
-               panel->backlight.active_low_pwm = ctl & BLM_POLARITY_PNV;
-
-       panel->backlight.pwm_level_max = ctl >> 17;
-
-       if (!panel->backlight.pwm_level_max) {
-               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
-               panel->backlight.pwm_level_max >>= 1;
-       }
-
-       if (!panel->backlight.pwm_level_max)
-               return -ENODEV;
-
-       if (panel->backlight.combination_mode)
-               panel->backlight.pwm_level_max *= 0xff;
-
-       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
-
-       val = i9xx_get_backlight(connector, unused);
-       val = intel_panel_invert_pwm_level(connector, val);
-       val = clamp(val, panel->backlight.pwm_level_min, panel->backlight.pwm_level_max);
-
-       panel->backlight.pwm_enabled = val != 0;
-
-       return 0;
-}
-
-static int i965_setup_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 ctl, ctl2;
-
-       ctl2 = intel_de_read(dev_priv, BLC_PWM_CTL2);
-       panel->backlight.combination_mode = ctl2 & BLM_COMBINATION_MODE;
-       panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
-
-       ctl = intel_de_read(dev_priv, BLC_PWM_CTL);
-       panel->backlight.pwm_level_max = ctl >> 16;
-
-       if (!panel->backlight.pwm_level_max)
-               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
-
-       if (!panel->backlight.pwm_level_max)
-               return -ENODEV;
-
-       if (panel->backlight.combination_mode)
-               panel->backlight.pwm_level_max *= 0xff;
-
-       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
-
-       panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
-
-       return 0;
-}
-
-static int vlv_setup_backlight(struct intel_connector *connector, enum pipe pipe)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 ctl, ctl2;
-
-       if (drm_WARN_ON(&dev_priv->drm, pipe != PIPE_A && pipe != PIPE_B))
-               return -ENODEV;
-
-       ctl2 = intel_de_read(dev_priv, VLV_BLC_PWM_CTL2(pipe));
-       panel->backlight.active_low_pwm = ctl2 & BLM_POLARITY_I965;
-
-       ctl = intel_de_read(dev_priv, VLV_BLC_PWM_CTL(pipe));
-       panel->backlight.pwm_level_max = ctl >> 16;
-
-       if (!panel->backlight.pwm_level_max)
-               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
-
-       if (!panel->backlight.pwm_level_max)
-               return -ENODEV;
-
-       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
-
-       panel->backlight.pwm_enabled = ctl2 & BLM_PWM_ENABLE;
-
-       return 0;
-}
-
-static int
-bxt_setup_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 pwm_ctl, val;
-
-       panel->backlight.controller = dev_priv->vbt.backlight.controller;
-
-       pwm_ctl = intel_de_read(dev_priv,
-                               BXT_BLC_PWM_CTL(panel->backlight.controller));
-
-       /* Controller 1 uses the utility pin. */
-       if (panel->backlight.controller == 1) {
-               val = intel_de_read(dev_priv, UTIL_PIN_CTL);
-               panel->backlight.util_pin_active_low =
-                                       val & UTIL_PIN_POLARITY;
-       }
-
-       panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
-       panel->backlight.pwm_level_max =
-               intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
-
-       if (!panel->backlight.pwm_level_max)
-               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
-
-       if (!panel->backlight.pwm_level_max)
-               return -ENODEV;
-
-       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
-
-       panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
-
-       return 0;
-}
-
-static int
-cnp_setup_backlight(struct intel_connector *connector, enum pipe unused)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-       u32 pwm_ctl;
-
-       /*
-        * CNP has the BXT implementation of backlight, but with only one
-        * controller. TODO: ICP has multiple controllers but we only use
-        * controller 0 for now.
-        */
-       panel->backlight.controller = 0;
-
-       pwm_ctl = intel_de_read(dev_priv,
-                               BXT_BLC_PWM_CTL(panel->backlight.controller));
-
-       panel->backlight.active_low_pwm = pwm_ctl & BXT_BLC_PWM_POLARITY;
-       panel->backlight.pwm_level_max =
-               intel_de_read(dev_priv, BXT_BLC_PWM_FREQ(panel->backlight.controller));
-
-       if (!panel->backlight.pwm_level_max)
-               panel->backlight.pwm_level_max = get_backlight_max_vbt(connector);
-
-       if (!panel->backlight.pwm_level_max)
-               return -ENODEV;
-
-       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
-
-       panel->backlight.pwm_enabled = pwm_ctl & BXT_BLC_PWM_ENABLE;
-
-       return 0;
-}
-
-static int ext_pwm_setup_backlight(struct intel_connector *connector,
-                                  enum pipe pipe)
-{
-       struct drm_device *dev = connector->base.dev;
-       struct drm_i915_private *dev_priv = to_i915(dev);
-       struct intel_panel *panel = &connector->panel;
-       const char *desc;
-       u32 level;
-
-       /* Get the right PWM chip for DSI backlight according to VBT */
-       if (dev_priv->vbt.dsi.config->pwm_blc == PPS_BLC_PMIC) {
-               panel->backlight.pwm = pwm_get(dev->dev, "pwm_pmic_backlight");
-               desc = "PMIC";
-       } else {
-               panel->backlight.pwm = pwm_get(dev->dev, "pwm_soc_backlight");
-               desc = "SoC";
-       }
-
-       if (IS_ERR(panel->backlight.pwm)) {
-               drm_err(&dev_priv->drm, "Failed to get the %s PWM chip\n",
-                       desc);
-               panel->backlight.pwm = NULL;
-               return -ENODEV;
-       }
-
-       panel->backlight.pwm_level_max = 100; /* 100% */
-       panel->backlight.pwm_level_min = get_backlight_min_vbt(connector);
-
-#ifdef notyet
-       if (pwm_is_enabled(panel->backlight.pwm)) {
-               /* PWM is already enabled, use existing settings */
-               pwm_get_state(panel->backlight.pwm, &panel->backlight.pwm_state);
-
-               level = pwm_get_relative_duty_cycle(&panel->backlight.pwm_state,
-                                                   100);
-               level = intel_panel_invert_pwm_level(connector, level);
-               panel->backlight.pwm_enabled = true;
-
-               drm_dbg_kms(&dev_priv->drm, "PWM already enabled at freq %ld, VBT freq %d, level %d\n",
-                           NSEC_PER_SEC / (unsigned long)panel->backlight.pwm_state.period,
-                           get_vbt_pwm_freq(dev_priv), level);
-       } else {
-               /* Set period from VBT frequency, leave other settings at 0. */
-               panel->backlight.pwm_state.period =
-                       NSEC_PER_SEC / get_vbt_pwm_freq(dev_priv);
-       }
-#else
-       STUB();
-#endif
-
-       drm_info(&dev_priv->drm, "Using %s PWM for LCD backlight control\n",
-                desc);
-       return 0;
-}
-
-static void intel_pwm_set_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct intel_panel *panel = &connector->panel;
-
-       panel->backlight.pwm_funcs->set(conn_state,
-                                      intel_panel_invert_pwm_level(connector, level));
-}
-
-static u32 intel_pwm_get_backlight(struct intel_connector *connector, enum pipe pipe)
-{
-       struct intel_panel *panel = &connector->panel;
-
-       return intel_panel_invert_pwm_level(connector,
-                                           panel->backlight.pwm_funcs->get(connector, pipe));
-}
-
-static void intel_pwm_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                      const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct intel_panel *panel = &connector->panel;
-
-       panel->backlight.pwm_funcs->enable(crtc_state, conn_state,
-                                          intel_panel_invert_pwm_level(connector, level));
-}
-
-static void intel_pwm_disable_backlight(const struct drm_connector_state *conn_state, u32 level)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct intel_panel *panel = &connector->panel;
-
-       panel->backlight.pwm_funcs->disable(conn_state,
-                                           intel_panel_invert_pwm_level(connector, level));
-}
-
-static int intel_pwm_setup_backlight(struct intel_connector *connector, enum pipe pipe)
-{
-       struct intel_panel *panel = &connector->panel;
-       int ret = panel->backlight.pwm_funcs->setup(connector, pipe);
-
-       if (ret < 0)
-               return ret;
-
-       panel->backlight.min = panel->backlight.pwm_level_min;
-       panel->backlight.max = panel->backlight.pwm_level_max;
-       panel->backlight.level = intel_pwm_get_backlight(connector, pipe);
-       panel->backlight.enabled = panel->backlight.pwm_enabled;
-
-       return 0;
-}
-
-void intel_panel_update_backlight(struct intel_atomic_state *state,
-                                 struct intel_encoder *encoder,
-                                 const struct intel_crtc_state *crtc_state,
-                                 const struct drm_connector_state *conn_state)
-{
-       struct intel_connector *connector = to_intel_connector(conn_state->connector);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-       struct intel_panel *panel = &connector->panel;
-
-       if (!panel->backlight.present)
-               return;
-
-       mutex_lock(&dev_priv->backlight_lock);
-       if (!panel->backlight.enabled)
-               __intel_panel_enable_backlight(crtc_state, conn_state);
-
-       mutex_unlock(&dev_priv->backlight_lock);
-}
-
-int intel_panel_setup_backlight(struct drm_connector *connector, enum pipe pipe)
-{
-       struct drm_i915_private *dev_priv = to_i915(connector->dev);
-       struct intel_connector *intel_connector = to_intel_connector(connector);
-       struct intel_panel *panel = &intel_connector->panel;
-       int ret;
-
-       if (!dev_priv->vbt.backlight.present) {
-               if (dev_priv->quirks & QUIRK_BACKLIGHT_PRESENT) {
-                       drm_dbg_kms(&dev_priv->drm,
-                                   "no backlight present per VBT, but present per quirk\n");
-               } else {
-                       drm_dbg_kms(&dev_priv->drm,
-                                   "no backlight present per VBT\n");
-                       return 0;
-               }
-       }
-
-       /* ensure intel_panel has been initialized first */
-       if (drm_WARN_ON(&dev_priv->drm, !panel->backlight.funcs))
-               return -ENODEV;
-
-       /* set level and max in panel struct */
-       mutex_lock(&dev_priv->backlight_lock);
-       ret = panel->backlight.funcs->setup(intel_connector, pipe);
-       mutex_unlock(&dev_priv->backlight_lock);
-
-       if (ret) {
-               drm_dbg_kms(&dev_priv->drm,
-                           "failed to setup backlight for connector %s\n",
-                           connector->name);
-               return ret;
-       }
-
-       panel->backlight.present = true;
-
-       drm_dbg_kms(&dev_priv->drm,
-                   "Connector %s backlight initialized, %s, brightness %u/%u\n",
-                   connector->name,
-                   enableddisabled(panel->backlight.enabled),
-                   panel->backlight.level, panel->backlight.max);
-
-       return 0;
-}
-
-static void intel_panel_destroy_backlight(struct intel_panel *panel)
-{
-       /* dispose of the pwm */
-       if (panel->backlight.pwm)
-               pwm_put(panel->backlight.pwm);
-
-       panel->backlight.present = false;
-}
-
-static const struct intel_panel_bl_funcs bxt_pwm_funcs = {
-       .setup = bxt_setup_backlight,
-       .enable = bxt_enable_backlight,
-       .disable = bxt_disable_backlight,
-       .set = bxt_set_backlight,
-       .get = bxt_get_backlight,
-       .hz_to_pwm = bxt_hz_to_pwm,
-};
-
-static const struct intel_panel_bl_funcs cnp_pwm_funcs = {
-       .setup = cnp_setup_backlight,
-       .enable = cnp_enable_backlight,
-       .disable = cnp_disable_backlight,
-       .set = bxt_set_backlight,
-       .get = bxt_get_backlight,
-       .hz_to_pwm = cnp_hz_to_pwm,
-};
-
-static const struct intel_panel_bl_funcs lpt_pwm_funcs = {
-       .setup = lpt_setup_backlight,
-       .enable = lpt_enable_backlight,
-       .disable = lpt_disable_backlight,
-       .set = lpt_set_backlight,
-       .get = lpt_get_backlight,
-       .hz_to_pwm = lpt_hz_to_pwm,
-};
-
-static const struct intel_panel_bl_funcs spt_pwm_funcs = {
-       .setup = lpt_setup_backlight,
-       .enable = lpt_enable_backlight,
-       .disable = lpt_disable_backlight,
-       .set = lpt_set_backlight,
-       .get = lpt_get_backlight,
-       .hz_to_pwm = spt_hz_to_pwm,
-};
-
-static const struct intel_panel_bl_funcs pch_pwm_funcs = {
-       .setup = pch_setup_backlight,
-       .enable = pch_enable_backlight,
-       .disable = pch_disable_backlight,
-       .set = pch_set_backlight,
-       .get = pch_get_backlight,
-       .hz_to_pwm = pch_hz_to_pwm,
-};
-
-static const struct intel_panel_bl_funcs ext_pwm_funcs = {
-       .setup = ext_pwm_setup_backlight,
-       .enable = ext_pwm_enable_backlight,
-       .disable = ext_pwm_disable_backlight,
-       .set = ext_pwm_set_backlight,
-       .get = ext_pwm_get_backlight,
-};
-
-static const struct intel_panel_bl_funcs vlv_pwm_funcs = {
-       .setup = vlv_setup_backlight,
-       .enable = vlv_enable_backlight,
-       .disable = vlv_disable_backlight,
-       .set = vlv_set_backlight,
-       .get = vlv_get_backlight,
-       .hz_to_pwm = vlv_hz_to_pwm,
-};
-
-static const struct intel_panel_bl_funcs i965_pwm_funcs = {
-       .setup = i965_setup_backlight,
-       .enable = i965_enable_backlight,
-       .disable = i965_disable_backlight,
-       .set = i9xx_set_backlight,
-       .get = i9xx_get_backlight,
-       .hz_to_pwm = i965_hz_to_pwm,
-};
-
-static const struct intel_panel_bl_funcs i9xx_pwm_funcs = {
-       .setup = i9xx_setup_backlight,
-       .enable = i9xx_enable_backlight,
-       .disable = i9xx_disable_backlight,
-       .set = i9xx_set_backlight,
-       .get = i9xx_get_backlight,
-       .hz_to_pwm = i9xx_hz_to_pwm,
-};
-
-static const struct intel_panel_bl_funcs pwm_bl_funcs = {
-       .setup = intel_pwm_setup_backlight,
-       .enable = intel_pwm_enable_backlight,
-       .disable = intel_pwm_disable_backlight,
-       .set = intel_pwm_set_backlight,
-       .get = intel_pwm_get_backlight,
-};
-
-/* Set up chip specific backlight functions */
-static void
-intel_panel_init_backlight_funcs(struct intel_panel *panel)
-{
-       struct intel_connector *connector =
-               container_of(panel, struct intel_connector, panel);
-       struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
-
-       if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI &&
-           intel_dsi_dcs_init_backlight_funcs(connector) == 0)
-               return;
-
-       if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv)) {
-               panel->backlight.pwm_funcs = &bxt_pwm_funcs;
-       } else if (INTEL_PCH_TYPE(dev_priv) >= PCH_CNP) {
-               panel->backlight.pwm_funcs = &cnp_pwm_funcs;
-       } else if (INTEL_PCH_TYPE(dev_priv) >= PCH_LPT) {
-               if (HAS_PCH_LPT(dev_priv))
-                       panel->backlight.pwm_funcs = &lpt_pwm_funcs;
-               else
-                       panel->backlight.pwm_funcs = &spt_pwm_funcs;
-       } else if (HAS_PCH_SPLIT(dev_priv)) {
-               panel->backlight.pwm_funcs = &pch_pwm_funcs;
-       } else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
-               if (connector->base.connector_type == DRM_MODE_CONNECTOR_DSI) {
-                       panel->backlight.pwm_funcs = &ext_pwm_funcs;
-               } else {
-                       panel->backlight.pwm_funcs = &vlv_pwm_funcs;
-               }
-       } else if (DISPLAY_VER(dev_priv) == 4) {
-               panel->backlight.pwm_funcs = &i965_pwm_funcs;
-       } else {
-               panel->backlight.pwm_funcs = &i9xx_pwm_funcs;
-       }
-
-       if (connector->base.connector_type == DRM_MODE_CONNECTOR_eDP &&
-           intel_dp_aux_init_backlight_funcs(connector) == 0)
-               return;
-
-       /* We're using a standard PWM backlight interface */
-       panel->backlight.funcs = &pwm_bl_funcs;
-}
-
 enum drm_connector_status
 intel_panel_detect(struct drm_connector *connector, bool force)
 {
index 1d340f7..67dbb15 100644 (file)
@@ -8,15 +8,13 @@
 
 #include <linux/types.h>
 
-#include "intel_display.h"
-
+enum drm_connector_status;
 struct drm_connector;
 struct drm_connector_state;
 struct drm_display_mode;
+struct drm_i915_private;
 struct intel_connector;
-struct intel_crtc;
 struct intel_crtc_state;
-struct intel_encoder;
 struct intel_panel;
 
 int intel_panel_init(struct intel_panel *panel,
@@ -31,17 +29,6 @@ int intel_pch_panel_fitting(struct intel_crtc_state *crtc_state,
                            const struct drm_connector_state *conn_state);
 int intel_gmch_panel_fitting(struct intel_crtc_state *crtc_state,
                             const struct drm_connector_state *conn_state);
-void intel_panel_set_backlight_acpi(const struct drm_connector_state *conn_state,
-                                   u32 level, u32 max);
-int intel_panel_setup_backlight(struct drm_connector *connector,
-                               enum pipe pipe);
-void intel_panel_enable_backlight(const struct intel_crtc_state *crtc_state,
-                                 const struct drm_connector_state *conn_state);
-void intel_panel_update_backlight(struct intel_atomic_state *state,
-                                 struct intel_encoder *encoder,
-                                 const struct intel_crtc_state *crtc_state,
-                                 const struct drm_connector_state *conn_state);
-void intel_panel_disable_backlight(const struct drm_connector_state *old_conn_state);
 struct drm_display_mode *
 intel_panel_edid_downclock_mode(struct intel_connector *connector,
                                const struct drm_display_mode *fixed_mode);
@@ -49,22 +36,5 @@ struct drm_display_mode *
 intel_panel_edid_fixed_mode(struct intel_connector *connector);
 struct drm_display_mode *
 intel_panel_vbt_fixed_mode(struct intel_connector *connector);
-void intel_panel_set_pwm_level(const struct drm_connector_state *conn_state, u32 level);
-u32 intel_panel_invert_pwm_level(struct intel_connector *connector, u32 level);
-u32 intel_panel_backlight_level_to_pwm(struct intel_connector *connector, u32 level);
-u32 intel_panel_backlight_level_from_pwm(struct intel_connector *connector, u32 val);
-
-#if IS_ENABLED(CONFIG_BACKLIGHT_CLASS_DEVICE)
-int intel_backlight_device_register(struct intel_connector *connector);
-void intel_backlight_device_unregister(struct intel_connector *connector);
-#else /* CONFIG_BACKLIGHT_CLASS_DEVICE */
-static inline int intel_backlight_device_register(struct intel_connector *connector)
-{
-       return 0;
-}
-static inline void intel_backlight_device_unregister(struct intel_connector *connector)
-{
-}
-#endif /* CONFIG_BACKLIGHT_CLASS_DEVICE */
 
 #endif /* __INTEL_PANEL_H__ */
index e3c33fa..31ddd07 100644 (file)
@@ -32,6 +32,7 @@
 
 #include "i915_drv.h"
 #include "intel_atomic.h"
+#include "intel_backlight.h"
 #include "intel_connector.h"
 #include "intel_crtc.h"
 #include "intel_de.h"