regulator: AXP20x: Add support for regulators subsystem

AXP202 and AXP209 come with two synchronous step-down DC-DCs and five
LDOs. This patch introduces basic support for those regulators.

Signed-off-by: Carlo Caione <carlo@caione.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

3 files changed, 293 insertions, 0 deletions

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 903eb37f047a..65e5d7d1b35a 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -139,6 +139,13 @@ config REGULATOR_AS3722
 	  AS3722 PMIC. This will enable support for all the software
 	  controllable DCDC/LDO regulators.
 
+config REGULATOR_AXP20X
+	tristate "X-POWERS AXP20X PMIC Regulators"
+	depends on MFD_AXP20X
+	help
+	  This driver provides support for the voltage regulators on the
+	  AXP20X PMIC.
+
 config REGULATOR_BCM590XX
 	tristate "Broadcom BCM590xx PMU Regulators"
 	depends on MFD_BCM590XX
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 12ef277a48b4..c14696b290c0 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_REGULATOR_ANATOP) += anatop-regulator.o
 obj-$(CONFIG_REGULATOR_ARIZONA) += arizona-micsupp.o arizona-ldo1.o
 obj-$(CONFIG_REGULATOR_AS3711) += as3711-regulator.o
 obj-$(CONFIG_REGULATOR_AS3722) += as3722-regulator.o
+obj-$(CONFIG_REGULATOR_AXP20X) += axp20x-regulator.o
 obj-$(CONFIG_REGULATOR_BCM590XX) += bcm590xx-regulator.o
 obj-$(CONFIG_REGULATOR_DA903X)	+= da903x.o
 obj-$(CONFIG_REGULATOR_DA9052)	+= da9052-regulator.o
diff --git a/drivers/regulator/axp20x-regulator.c b/drivers/regulator/axp20x-regulator.c
new file mode 100644
index 000000000000..78a29e60f53a
--- /dev/null
+++ b/drivers/regulator/axp20x-regulator.c
@@ -0,0 +1,285 @@
+/*
+ * AXP20x regulators driver.
+ *
+ * Copyright (C) 2013 Carlo Caione <carlo@caione.org>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/axp20x.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
+
+#define AXP20X_IO_ENABLED		0x03
+#define AXP20X_IO_DISABLED		0x07
+
+#define AXP20X_WORKMODE_DCDC2_MASK	BIT(2)
+#define AXP20X_WORKMODE_DCDC3_MASK	BIT(1)
+
+#define AXP20X_FREQ_DCDC_MASK		0x0f
+
+#define AXP20X_DESC_IO(_id, _supply, _min, _max, _step, _vreg, _vmask, _ereg,   \
+		       _emask, _enable_val, _disable_val)			\
+	[AXP20X_##_id] = {							\
+		.name		= #_id,						\
+		.supply_name	= (_supply),					\
+		.type		= REGULATOR_VOLTAGE,				\
+		.id		= AXP20X_##_id,					\
+		.n_voltages	= (((_max) - (_min)) / (_step) + 1),		\
+		.owner		= THIS_MODULE,					\
+		.min_uV		= (_min) * 1000,				\
+		.uV_step	= (_step) * 1000,				\
+		.vsel_reg	= (_vreg),					\
+		.vsel_mask	= (_vmask),					\
+		.enable_reg	= (_ereg),					\
+		.enable_mask	= (_emask),					\
+		.enable_val	= (_enable_val),				\
+		.disable_val	= (_disable_val),				\
+		.ops		= &axp20x_ops,					\
+	}
+
+#define AXP20X_DESC(_id, _supply, _min, _max, _step, _vreg, _vmask, _ereg,	\
+		    _emask) 							\
+	[AXP20X_##_id] = {							\
+		.name		= #_id,						\
+		.supply_name	= (_supply),					\
+		.type		= REGULATOR_VOLTAGE,				\
+		.id		= AXP20X_##_id,					\
+		.n_voltages	= (((_max) - (_min)) / (_step) + 1),		\
+		.owner		= THIS_MODULE,					\
+		.min_uV		= (_min) * 1000,				\
+		.uV_step	= (_step) * 1000,				\
+		.vsel_reg	= (_vreg),					\
+		.vsel_mask	= (_vmask),					\
+		.enable_reg	= (_ereg),					\
+		.enable_mask	= (_emask),					\
+		.ops		= &axp20x_ops,					\
+	}
+
+#define AXP20X_DESC_FIXED(_id, _supply, _volt)					\
+	[AXP20X_##_id] = {							\
+		.name		= #_id,						\
+		.supply_name	= (_supply),					\
+		.type		= REGULATOR_VOLTAGE,				\
+		.id		= AXP20X_##_id,					\
+		.n_voltages	= 1,						\
+		.owner		= THIS_MODULE,					\
+		.min_uV		= (_volt) * 1000,				\
+		.ops		= &axp20x_ops_fixed				\
+	}
+
+#define AXP20X_DESC_TABLE(_id, _supply, _table, _vreg, _vmask, _ereg, _emask)	\
+	[AXP20X_##_id] = {							\
+		.name		= #_id,						\
+		.supply_name	= (_supply),					\
+		.type		= REGULATOR_VOLTAGE,				\
+		.id		= AXP20X_##_id,					\
+		.n_voltages	= ARRAY_SIZE(_table),				\
+		.owner		= THIS_MODULE,					\
+		.vsel_reg	= (_vreg),					\
+		.vsel_mask	= (_vmask),					\
+		.enable_reg	= (_ereg),					\
+		.enable_mask	= (_emask),					\
+		.volt_table	= (_table),					\
+		.ops		= &axp20x_ops_table,				\
+	}
+
+static const int axp20x_ldo4_data[] = { 1250000, 1300000, 1400000, 1500000, 1600000,
+					1700000, 1800000, 1900000, 2000000, 2500000,
+					2700000, 2800000, 3000000, 3100000, 3200000,
+					3300000 };
+
+static struct regulator_ops axp20x_ops_fixed = {
+	.list_voltage		= regulator_list_voltage_linear,
+};
+
+static struct regulator_ops axp20x_ops_table = {
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.list_voltage		= regulator_list_voltage_table,
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.is_enabled		= regulator_is_enabled_regmap,
+};
+
+static struct regulator_ops axp20x_ops = {
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.list_voltage		= regulator_list_voltage_linear,
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.is_enabled		= regulator_is_enabled_regmap,
+};
+
+static const struct regulator_desc axp20x_regulators[] = {
+	AXP20X_DESC(DCDC2, "vin2", 700, 2275, 25, AXP20X_DCDC2_V_OUT, 0x3f,
+		    AXP20X_PWR_OUT_CTRL, 0x10),
+	AXP20X_DESC(DCDC3, "vin3", 700, 3500, 25, AXP20X_DCDC3_V_OUT, 0x7f,
+		    AXP20X_PWR_OUT_CTRL, 0x02),
+	AXP20X_DESC_FIXED(LDO1, "acin", 1300),
+	AXP20X_DESC(LDO2, "ldo24in", 1800, 3300, 100, AXP20X_LDO24_V_OUT, 0xf0,
+		    AXP20X_PWR_OUT_CTRL, 0x04),
+	AXP20X_DESC(LDO3, "ldo3in", 700, 3500, 25, AXP20X_LDO3_V_OUT, 0x7f,
+		    AXP20X_PWR_OUT_CTRL, 0x40),
+	AXP20X_DESC_TABLE(LDO4, "ldo24in", axp20x_ldo4_data, AXP20X_LDO24_V_OUT, 0x0f,
+			  AXP20X_PWR_OUT_CTRL, 0x08),
+	AXP20X_DESC_IO(LDO5, "ldo5in", 1800, 3300, 100, AXP20X_LDO5_V_OUT, 0xf0,
+		       AXP20X_GPIO0_CTRL, 0x07, AXP20X_IO_ENABLED,
+		       AXP20X_IO_DISABLED),
+};
+
+#define AXP_MATCH(_name, _id) \
+	[AXP20X_##_id] = { \
+		.name		= #_name, \
+		.driver_data	= (void *) &axp20x_regulators[AXP20X_##_id], \
+	}
+
+static struct of_regulator_match axp20x_matches[] = {
+	AXP_MATCH(dcdc2, DCDC2),
+	AXP_MATCH(dcdc3, DCDC3),
+	AXP_MATCH(ldo1, LDO1),
+	AXP_MATCH(ldo2, LDO2),
+	AXP_MATCH(ldo3, LDO3),
+	AXP_MATCH(ldo4, LDO4),
+	AXP_MATCH(ldo5, LDO5),
+};
+
+static int axp20x_set_dcdc_freq(struct platform_device *pdev, u32 dcdcfreq)
+{
+	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
+
+	if (dcdcfreq < 750) {
+		dcdcfreq = 750;
+		dev_warn(&pdev->dev, "DCDC frequency too low. Set to 750kHz\n");
+	}
+
+	if (dcdcfreq > 1875) {
+		dcdcfreq = 1875;
+		dev_warn(&pdev->dev, "DCDC frequency too high. Set to 1875kHz\n");
+	}
+
+	dcdcfreq = (dcdcfreq - 750) / 75;
+
+	return regmap_update_bits(axp20x->regmap, AXP20X_DCDC_FREQ,
+				  AXP20X_FREQ_DCDC_MASK, dcdcfreq);
+}
+
+static int axp20x_regulator_parse_dt(struct platform_device *pdev)
+{
+	struct device_node *np, *regulators;
+	int ret;
+	u32 dcdcfreq;
+
+	np = of_node_get(pdev->dev.parent->of_node);
+	if (!np)
+		return 0;
+
+	regulators = of_find_node_by_name(np, "regulators");
+	if (!regulators) {
+		dev_warn(&pdev->dev, "regulators node not found\n");
+	} else {
+		ret = of_regulator_match(&pdev->dev, regulators, axp20x_matches,
+					 ARRAY_SIZE(axp20x_matches));
+		if (ret < 0) {
+			dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
+			return ret;
+		}
+
+		dcdcfreq = 1500;
+		of_property_read_u32(regulators, "x-powers,dcdc-freq", &dcdcfreq);
+		ret = axp20x_set_dcdc_freq(pdev, dcdcfreq);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "Error setting dcdc frequency: %d\n", ret);
+			return ret;
+		}
+
+		of_node_put(regulators);
+	}
+
+	return 0;
+}
+
+static int axp20x_set_dcdc_workmode(struct regulator_dev *rdev, int id, u32 workmode)
+{
+	unsigned int mask = AXP20X_WORKMODE_DCDC2_MASK;
+
+	if ((id != AXP20X_DCDC2) && (id != AXP20X_DCDC3))
+		return -EINVAL;
+
+	if (id == AXP20X_DCDC3)
+		mask = AXP20X_WORKMODE_DCDC3_MASK;
+
+	workmode <<= ffs(mask) - 1;
+
+	return regmap_update_bits(rdev->regmap, AXP20X_DCDC_MODE, mask, workmode);
+}
+
+static int axp20x_regulator_probe(struct platform_device *pdev)
+{
+	struct regulator_dev *rdev;
+	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
+	struct regulator_config config = { };
+	struct regulator_init_data *init_data;
+	int ret, i;
+	u32 workmode;
+
+	ret = axp20x_regulator_parse_dt(pdev);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < AXP20X_REG_ID_MAX; i++) {
+		init_data = axp20x_matches[i].init_data;
+
+		config.dev = &pdev->dev;
+		config.init_data = init_data;
+		config.regmap = axp20x->regmap;
+		config.of_node = axp20x_matches[i].of_node;
+
+		rdev = devm_regulator_register(&pdev->dev, &axp20x_regulators[i],
+					       &config);
+		if (IS_ERR(rdev)) {
+			dev_err(&pdev->dev, "Failed to register %s\n",
+				axp20x_regulators[i].name);
+
+			return PTR_ERR(rdev);
+		}
+
+		ret = of_property_read_u32(axp20x_matches[i].of_node, "x-powers,dcdc-workmode",
+					   &workmode);
+		if (!ret) {
+			if (axp20x_set_dcdc_workmode(rdev, i, workmode))
+				dev_err(&pdev->dev, "Failed to set workmode on %s\n",
+					axp20x_regulators[i].name);
+		}
+	}
+
+	return 0;
+}
+
+static struct platform_driver axp20x_regulator_driver = {
+	.probe	= axp20x_regulator_probe,
+	.driver	= {
+		.name		= "axp20x-regulator",
+		.owner		= THIS_MODULE,
+	},
+};
+
+module_platform_driver(axp20x_regulator_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
+MODULE_DESCRIPTION("Regulator Driver for AXP20X PMIC");