Enforce voltage limits from the device tree. Enforcing the limits also

happens when regulators are registered.  As a consequence they will be
properly initialized even when the firmware doesn't do that.

ok patrick@

diff --git a/sys/dev/ofw/ofw_regulator.c b/sys/dev/ofw/ofw_regulator.c
index a728bdb..efd720a 100644 (file)
--- a/sys/dev/ofw/ofw_regulator.c
+++ b/sys/dev/ofw/ofw_regulator.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ofw_regulator.c,v 1.2 2017/11/18 13:48:50 kettenis Exp $      */
+/*     $OpenBSD: ofw_regulator.c,v 1.3 2017/12/16 21:12:03 kettenis Exp $      */
 /*
  * Copyright (c) 2016 Mark Kettenis
  *
@@ -30,6 +30,18 @@ LIST_HEAD(, regulator_device) regulator_devices =
 void
 regulator_register(struct regulator_device *rd)
 {
+       rd->rd_min = OF_getpropint(rd->rd_node, "regulator-min-microvolt", 0);
+       rd->rd_max = OF_getpropint(rd->rd_node, "regulator-max-microvolt", ~0);
+       KASSERT(rd->rd_min <= rd->rd_max);
+
+       if (rd->rd_get_voltage && rd->rd_set_voltage) {
+               uint32_t voltage = rd->rd_get_voltage(rd->rd_cookie);
+               if (voltage < rd->rd_min)
+                       rd->rd_set_voltage(rd->rd_cookie, rd->rd_min);
+               if (voltage > rd->rd_max)
+                       rd->rd_set_voltage(rd->rd_cookie, rd->rd_max);
+       }
+
        rd->rd_phandle = OF_getpropint(rd->rd_node, "phandle", 0);
        if (rd->rd_phandle == 0)
                return;
@@ -127,8 +139,12 @@ regulator_set_voltage(uint32_t phandle, uint32_t voltage)
                        break;
        }
 
+       /* Check limits. */
+       if (rd && (voltage < rd->rd_min || voltage > rd->rd_max))
+               return EINVAL;
+
        if (rd && rd->rd_set_voltage)
                return rd->rd_set_voltage(rd->rd_cookie, voltage);
 
-       return -1;
+       return ENODEV;
 }

diff --git a/sys/dev/ofw/ofw_regulator.h b/sys/dev/ofw/ofw_regulator.h
index d3abf51..006ecfa 100644 (file)
--- a/sys/dev/ofw/ofw_regulator.h
+++ b/sys/dev/ofw/ofw_regulator.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ofw_regulator.h,v 1.3 2017/11/18 21:03:23 kettenis Exp $      */
+/*     $OpenBSD: ofw_regulator.h,v 1.4 2017/12/16 21:12:03 kettenis Exp $      */
 /*
  * Copyright (c) 2016 Mark Kettenis
  *
@@ -24,6 +24,8 @@ struct regulator_device {
        uint32_t (*rd_get_voltage)(void *);
        int     (*rd_set_voltage)(void *, uint32_t);
 
+       uint32_t rd_min, rd_max;
+
        LIST_ENTRY(regulator_device) rd_list;
        uint32_t rd_phandle;
 };