stm32mp: regulator: add SoC pwr regulator support

This driver binds and manages the following regulator of
SoC's PWR block :
  - reg11
  - reg18
  - usb33

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>

arch/arm/mach-stm32mp/Makefile

@@ -9,3 +9,4 @@ obj-y += syscon.o
 
 obj-$(CONFIG_SPL_BUILD) += spl.o
 obj-$(CONFIG_ARMV7_PSCI) += psci.o
+obj-$(CONFIG_$(SPL_)DM_REGULATOR) += pwr_regulator.o

arch/arm/mach-stm32mp/include/mach/stm32.h

@@ -28,6 +28,7 @@
 enum {
 	STM32MP_SYSCON_UNKNOWN,
 	STM32MP_SYSCON_STGEN,
+	STM32MP_SYSCON_PWR,
 };
 
 /*

arch/arm/mach-stm32mp/pwr_regulator.c

@@ -0,0 +1,274 @@
+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+/*
+ * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <regmap.h>
+#include <syscon.h>
+#include <power/pmic.h>
+#include <power/regulator.h>
+
+#define STM32MP_PWR_CR3 0xc
+#define STM32MP_PWR_CR3_USB33DEN BIT(24)
+#define STM32MP_PWR_CR3_USB33RDY BIT(26)
+#define STM32MP_PWR_CR3_REG18DEN BIT(28)
+#define STM32MP_PWR_CR3_REG18RDY BIT(29)
+#define STM32MP_PWR_CR3_REG11DEN BIT(30)
+#define STM32MP_PWR_CR3_REG11RDY BIT(31)
+
+struct stm32mp_pwr_reg_info {
+	u32 enable;
+	u32 ready;
+	char *name;
+};
+
+struct stm32mp_pwr_priv {
+	struct regmap *regmap;
+};
+
+static int stm32mp_pwr_write(struct udevice *dev, uint reg,
+			     const uint8_t *buff, int len)
+{
+	struct stm32mp_pwr_priv *priv = dev_get_priv(dev);
+	u32 val = *(u32 *)buff;
+
+	if (len != 4)
+		return -EINVAL;
+
+	return regmap_write(priv->regmap, STM32MP_PWR_CR3, val);
+}
+
+static int stm32mp_pwr_read(struct udevice *dev, uint reg, uint8_t *buff,
+			    int len)
+{
+	struct stm32mp_pwr_priv *priv = dev_get_priv(dev);
+
+	if (len != 4)
+		return -EINVAL;
+
+	return regmap_read(priv->regmap, STM32MP_PWR_CR3, (u32 *)buff);
+}
+
+static int stm32mp_pwr_ofdata_to_platdata(struct udevice *dev)
+{
+	struct stm32mp_pwr_priv *priv = dev_get_priv(dev);
+	struct regmap *regmap;
+
+	regmap = syscon_get_regmap_by_driver_data(STM32MP_SYSCON_PWR);
+	if (IS_ERR(regmap)) {
+		pr_err("%s: unable to find regmap (%ld)\n", __func__,
+		       PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+	priv->regmap = regmap;
+
+	return 0;
+}
+
+static const struct pmic_child_info pwr_children_info[] = {
+	{ .prefix = "reg", .driver = "stm32mp_pwr_regulator"},
+	{ .prefix = "usb", .driver = "stm32mp_pwr_regulator"},
+	{ },
+};
+
+static int stm32mp_pwr_bind(struct udevice *dev)
+{
+	int children;
+
+	children = pmic_bind_children(dev, dev->node, pwr_children_info);
+	if (!children)
+		dev_dbg(dev, "no child found\n");
+
+	return 0;
+}
+
+static struct dm_pmic_ops stm32mp_pwr_ops = {
+	.read = stm32mp_pwr_read,
+	.write = stm32mp_pwr_write,
+};
+
+static const struct udevice_id stm32mp_pwr_ids[] = {
+	{ .compatible = "st,stm32mp1,pwr-reg" },
+	{ }
+};
+
+U_BOOT_DRIVER(stm32mp_pwr_pmic) = {
+	.name = "stm32mp_pwr_pmic",
+	.id = UCLASS_PMIC,
+	.of_match = stm32mp_pwr_ids,
+	.bind = stm32mp_pwr_bind,
+	.ops = &stm32mp_pwr_ops,
+	.ofdata_to_platdata = stm32mp_pwr_ofdata_to_platdata,
+	.priv_auto_alloc_size = sizeof(struct stm32mp_pwr_priv),
+};
+
+static const struct stm32mp_pwr_reg_info stm32mp_pwr_reg11 = {
+	.enable = STM32MP_PWR_CR3_REG11DEN,
+	.ready = STM32MP_PWR_CR3_REG11RDY,
+	.name = "reg11"
+};
+
+static const struct stm32mp_pwr_reg_info stm32mp_pwr_reg18 = {
+	.enable = STM32MP_PWR_CR3_REG18DEN,
+	.ready = STM32MP_PWR_CR3_REG18RDY,
+	.name = "reg18"
+};
+
+static const struct stm32mp_pwr_reg_info stm32mp_pwr_usb33 = {
+	.enable = STM32MP_PWR_CR3_USB33DEN,
+	.ready = STM32MP_PWR_CR3_USB33RDY,
+	.name = "usb33"
+};
+
+static const struct stm32mp_pwr_reg_info *stm32mp_pwr_reg_infos[] = {
+	&stm32mp_pwr_reg11,
+	&stm32mp_pwr_reg18,
+	&stm32mp_pwr_usb33,
+	NULL
+};
+
+static int stm32mp_pwr_regulator_probe(struct udevice *dev)
+{
+	const struct stm32mp_pwr_reg_info **p = stm32mp_pwr_reg_infos;
+	struct dm_regulator_uclass_platdata *uc_pdata;
+
+	uc_pdata = dev_get_uclass_platdata(dev);
+
+	while (*p) {
+		int rc;
+
+		rc = dev_read_stringlist_search(dev, "regulator-name",
+						(*p)->name);
+		if (rc >= 0) {
+			dev_dbg(dev, "found regulator %s\n", (*p)->name);
+			break;
+		} else if (rc != -ENODATA) {
+			return rc;
+		}
+		p++;
+	}
+	if (!*p) {
+		int i = 0;
+		const char *s;
+
+		dev_dbg(dev, "regulator ");
+		while (dev_read_string_index(dev, "regulator-name",
+					     i++, &s) >= 0)
+			dev_dbg(dev, "%s'%s' ", (i > 1) ? ", " : "", s);
+		dev_dbg(dev, "%s not supported\n", (i > 2) ? "are" : "is");
+		return -EINVAL;
+	}
+
+	uc_pdata->type = REGULATOR_TYPE_FIXED;
+	dev->priv = (void *)*p;
+
+	return 0;
+}
+
+static int stm32mp_pwr_regulator_set_value(struct udevice *dev, int uV)
+{
+	struct dm_regulator_uclass_platdata *uc_pdata;
+
+	uc_pdata = dev_get_uclass_platdata(dev);
+	if (!uc_pdata)
+		return -ENXIO;
+
+	if (uc_pdata->min_uV != uV) {
+		dev_dbg(dev, "Invalid uV=%d for: %s\n", uV, uc_pdata->name);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int stm32mp_pwr_regulator_get_value(struct udevice *dev)
+{
+	struct dm_regulator_uclass_platdata *uc_pdata;
+
+	uc_pdata = dev_get_uclass_platdata(dev);
+	if (!uc_pdata)
+		return -ENXIO;
+
+	if (uc_pdata->min_uV != uc_pdata->max_uV) {
+		dev_dbg(dev, "Invalid constraints for: %s\n", uc_pdata->name);
+		return -EINVAL;
+	}
+
+	return uc_pdata->min_uV;
+}
+
+static int stm32mp_pwr_regulator_get_enable(struct udevice *dev)
+{
+	const struct stm32mp_pwr_reg_info *p = dev_get_priv(dev);
+	int rc;
+	u32 reg;
+
+	rc = pmic_read(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
+	if (rc)
+		return rc;
+
+	dev_dbg(dev, "%s id %s\n", p->name, (reg & p->enable) ? "on" : "off");
+
+	return (reg & p->enable) != 0;
+}
+
+static int stm32mp_pwr_regulator_set_enable(struct udevice *dev, bool enable)
+{
+	const struct stm32mp_pwr_reg_info *p = dev_get_priv(dev);
+	int rc;
+	u32 reg;
+	u32 time_start;
+
+	dev_dbg(dev, "Turning %s %s\n", enable ? "on" : "off", p->name);
+
+	rc = pmic_read(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
+	if (rc)
+		return rc;
+
+	/* if regulator is already in the wanted state, nothing to do */
+	if (!!(reg & p->enable) == enable)
+		return 0;
+
+	reg &= ~p->enable;
+	if (enable)
+		reg |= p->enable;
+
+	rc = pmic_write(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
+	if (rc)
+		return rc;
+
+	if (!enable)
+		return 0;
+
+	/* waiting ready for enable */
+	time_start = get_timer(0);
+	while (1) {
+		rc = pmic_read(dev->parent, 0, (uint8_t *)&reg, sizeof(reg));
+		if (rc)
+			return rc;
+		if (reg & p->ready)
+			break;
+		if (get_timer(time_start) > CONFIG_SYS_HZ) {
+			dev_dbg(dev, "%s: timeout\n", p->name);
+			return -ETIMEDOUT;
+		}
+	}
+	return 0;
+}
+
+static const struct dm_regulator_ops stm32mp_pwr_regulator_ops = {
+	.set_value  = stm32mp_pwr_regulator_set_value,
+	.get_value  = stm32mp_pwr_regulator_get_value,
+	.get_enable = stm32mp_pwr_regulator_get_enable,
+	.set_enable = stm32mp_pwr_regulator_set_enable,
+};
+
+U_BOOT_DRIVER(stm32mp_pwr_regulator) = {
+	.name = "stm32mp_pwr_regulator",
+	.id = UCLASS_REGULATOR,
+	.ops = &stm32mp_pwr_regulator_ops,
+	.probe = stm32mp_pwr_regulator_probe,
+};

arch/arm/mach-stm32mp/syscon.c

@@ -11,6 +11,8 @@
 static const struct udevice_id stm32mp_syscon_ids[] = {
 	{ .compatible = "st,stm32-stgen",
 	  .data = STM32MP_SYSCON_STGEN },
+	{ .compatible = "st,stm32mp1-pwr",
+	  .data = STM32MP_SYSCON_PWR },
 	{ }
 };