From 560e4370f9d00915475f0566939dfa7a8c453ab4 Mon Sep 17 00:00:00 2001
From: patrick <patrick@openbsd.org>
Date: Mon, 13 Aug 2018 15:14:27 +0000
Subject: [PATCH] Support GPIO-based voltage regulators.

ok kettenis@
---
 sys/dev/ofw/ofw_regulator.c | 120 +++++++++++++++++++++++++++++++++++-
 1 file changed, 118 insertions(+), 2 deletions(-)

diff --git a/sys/dev/ofw/ofw_regulator.c b/sys/dev/ofw/ofw_regulator.c
index 4c2c7152721..cd916e88139 100644
--- a/sys/dev/ofw/ofw_regulator.c
+++ b/sys/dev/ofw/ofw_regulator.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ofw_regulator.c,v 1.5 2018/08/02 09:45:17 kettenis Exp $	*/
+/*	$OpenBSD: ofw_regulator.c,v 1.6 2018/08/13 15:14:27 patrick Exp $	*/
 /*
  * Copyright (c) 2016 Mark Kettenis
  *
@@ -27,6 +27,9 @@
 LIST_HEAD(, regulator_device) regulator_devices =
 	LIST_HEAD_INITIALIZER(regulator_devices);
 
+uint32_t regulator_gpio_get_voltage(int);
+int regulator_gpio_set_voltage(int, uint32_t);
+
 void
 regulator_register(struct regulator_device *rd)
 {
@@ -149,6 +152,9 @@ regulator_get_voltage(uint32_t phandle)
 	if (OF_is_compatible(node, "regulator-fixed"))
 		return OF_getpropint(node, "regulator-min-voltage", 0);
 
+	if (OF_is_compatible(node, "regulator-gpio"))
+		return regulator_gpio_get_voltage(node);
+
 	return 0;
 }
 
@@ -157,7 +163,7 @@ regulator_set_voltage(uint32_t phandle, uint32_t voltage)
 {
 	struct regulator_device *rd;
 	uint32_t old, delta;
-	int error;
+	int error, node;
 
 	LIST_FOREACH(rd, &regulator_devices, rd_list) {
 		if (rd->rd_phandle == phandle)
@@ -178,5 +184,115 @@ regulator_set_voltage(uint32_t phandle, uint32_t voltage)
 		return error;
 	}
 
+	node = OF_getnodebyphandle(phandle);
+	if (node == 0)
+		return ENODEV;
+
+	if (OF_is_compatible(node, "regulator-gpio"))
+		return regulator_gpio_set_voltage(node, voltage);
+
 	return ENODEV;
 }
+
+uint32_t
+regulator_gpio_get_voltage(int node)
+{
+	uint32_t *gpio, *gpios, *states;
+	uint32_t idx, voltage;
+	size_t glen, slen;
+	int i;
+
+	pinctrl_byname(node, "default");
+
+	if ((glen = OF_getproplen(node, "gpios")) <= 0)
+		return EINVAL;
+	if ((slen = OF_getproplen(node, "states")) <= 0)
+		return EINVAL;
+
+	if (slen % (2 * sizeof(uint32_t)) != 0)
+		return EINVAL;
+
+	gpios = malloc(glen, M_TEMP, M_WAITOK);
+	states = malloc(slen, M_TEMP, M_WAITOK);
+
+	OF_getpropintarray(node, "gpios", gpios, glen);
+	OF_getpropintarray(node, "states", states, slen);
+
+	idx = 0;
+	gpio = gpios;
+	while (gpio && gpio < gpios + (glen / sizeof(uint32_t))) {
+		idx |= (1 << i);
+		gpio = gpio_controller_next_pin(gpio);
+		i++;
+	}
+
+	voltage = 0;
+	for (i = 0; i < slen / (2 * sizeof(uint32_t)); i++) {
+		if (states[2 * i + 1] == idx) {
+			voltage = states[2 * i];
+			break;
+		}
+	}
+	if (i >= slen / (2 * sizeof(uint32_t)))
+		return 0;
+
+	free(gpios, M_TEMP, glen);
+	free(states, M_TEMP, slen);
+
+	return voltage;
+}
+
+int
+regulator_gpio_set_voltage(int node, uint32_t voltage)
+{
+	uint32_t *gpio, *gpios, *states;
+	size_t glen, slen;
+	uint32_t min, max;
+	uint32_t idx;
+	int i;
+
+	pinctrl_byname(node, "default");
+
+	/* Check limits. */
+	min = OF_getpropint(node, "regulator-min-microvolt", 0);
+	max = OF_getpropint(node, "regulator-max-microvolt", 0);
+	if (voltage < min || voltage > max)
+		return EINVAL;
+
+	if ((glen = OF_getproplen(node, "gpios")) <= 0)
+		return EINVAL;
+	if ((slen = OF_getproplen(node, "states")) <= 0)
+		return EINVAL;
+
+	if (slen % (2 * sizeof(uint32_t)) != 0)
+		return EINVAL;
+
+	gpios = malloc(glen, M_TEMP, M_WAITOK);
+	states = malloc(slen, M_TEMP, M_WAITOK);
+
+	OF_getpropintarray(node, "gpios", gpios, glen);
+	OF_getpropintarray(node, "states", states, slen);
+
+	idx = 0;
+	for (i = 0; i < slen / (2 * sizeof(uint32_t)); i++) {
+		if (states[2 * i] < min || states[2 * i] > max)
+			continue;
+		if (states[2 * i] == voltage)
+			idx = states[2 * i + 1];
+	}
+	if (i >= slen / (2 * sizeof(uint32_t)))
+		return EINVAL;
+
+	i = 0;
+	gpio = gpios;
+	while (gpio && gpio < gpios + (glen / sizeof(uint32_t))) {
+		gpio_controller_set_pin(gpio, !!(idx & (1 << i)));
+		gpio = gpio_controller_next_pin(gpio);
+		i++;
+	}
+
+	free(gpios, M_TEMP, glen);
+	free(states, M_TEMP, slen);
+
+	return 0;
+}
-- 
2.20.1