regulator: max14577: Add support for MAX77836 regulators

Add support for MAX77836 chipset and its additional two LDO regulators.
These LDO regulators are controlled by the PMIC block with additional
regmap (different I2C slave address).

The MAX77836 charger and safeout regulators are almost identical to
MAX14577. The registers layout is the same, except values for charger's
current. The patch adds simple mapping between device type and supported
current by the charger regulator.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

2 files changed, 246 insertions, 38 deletions

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 903eb37f047a..f0cc9e6dac3a 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -266,11 +266,12 @@ config REGULATOR_LP8788
 	  This driver supports LP8788 voltage regulator chip.
 
 config REGULATOR_MAX14577
-	tristate "Maxim 14577 regulator"
+	tristate "Maxim 14577/77836 regulator"
 	depends on MFD_MAX14577
 	help
-	  This driver controls a Maxim 14577 regulator via I2C bus.
-	  The regulators include safeout LDO and current regulator 'CHARGER'.
+	  This driver controls a Maxim MAX14577/77836 regulator via I2C bus.
+	  The MAX14577 regulators include safeout LDO and charger current
+	  regulator. The MAX77836 has two additional LDOs.
 
 config REGULATOR_MAX1586
 	tristate "Maxim 1586/1587 voltage regulator"
diff --git a/drivers/regulator/max14577.c b/drivers/regulator/max14577.c
index ed60baaeceec..5d9c605cf534 100644
--- a/drivers/regulator/max14577.c
+++ b/drivers/regulator/max14577.c
@@ -1,5 +1,5 @@
 /*
- * max14577.c - Regulator driver for the Maxim 14577
+ * max14577.c - Regulator driver for the Maxim 14577/77836
  *
  * Copyright (C) 2013,2014 Samsung Electronics
  * Krzysztof Kozlowski <k.kozlowski@samsung.com>
@@ -22,6 +22,42 @@
 #include <linux/mfd/max14577-private.h>
 #include <linux/regulator/of_regulator.h>
 
+/*
+ * Valid limits of current for max14577 and max77836 chargers.
+ * They must correspond to MBCICHWRCL and MBCICHWRCH fields in CHGCTRL4
+ * register for given chipset.
+ */
+struct maxim_charger_current {
+	/* Minimal current, set in CHGCTRL4/MBCICHWRCL, uA */
+	unsigned int min;
+	/*
+	 * Minimal current when high setting is active,
+	 * set in CHGCTRL4/MBCICHWRCH, uA
+	 */
+	unsigned int high_start;
+	/* Value of one step in high setting, uA */
+	unsigned int high_step;
+	/* Maximum current of high setting, uA */
+	unsigned int max;
+};
+
+/* Table of valid charger currents for different Maxim chipsets */
+static const struct maxim_charger_current maxim_charger_currents[] = {
+	[MAXIM_DEVICE_TYPE_UNKNOWN] = { 0, 0, 0, 0 },
+	[MAXIM_DEVICE_TYPE_MAX14577] = {
+		.min		= MAX14577_REGULATOR_CURRENT_LIMIT_MIN,
+		.high_start	= MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_START,
+		.high_step	= MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_STEP,
+		.max		= MAX14577_REGULATOR_CURRENT_LIMIT_MAX,
+	},
+	[MAXIM_DEVICE_TYPE_MAX77836] = {
+		.min		= MAX77836_REGULATOR_CURRENT_LIMIT_MIN,
+		.high_start	= MAX77836_REGULATOR_CURRENT_LIMIT_HIGH_START,
+		.high_step	= MAX77836_REGULATOR_CURRENT_LIMIT_HIGH_STEP,
+		.max		= MAX77836_REGULATOR_CURRENT_LIMIT_MAX,
+	},
+};
+
 static int max14577_reg_is_enabled(struct regulator_dev *rdev)
 {
 	int rid = rdev_get_id(rdev);
@@ -47,6 +83,9 @@ static int max14577_reg_get_current_limit(struct regulator_dev *rdev)
 {
 	u8 reg_data;
 	struct regmap *rmap = rdev->regmap;
+	struct max14577 *max14577 = rdev_get_drvdata(rdev);
+	const struct maxim_charger_current *limits =
+		&maxim_charger_currents[max14577->dev_type];
 
 	if (rdev_get_id(rdev) != MAX14577_CHARGER)
 		return -EINVAL;
@@ -54,12 +93,11 @@ static int max14577_reg_get_current_limit(struct regulator_dev *rdev)
 	max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL4, &reg_data);
 
 	if ((reg_data & CHGCTRL4_MBCICHWRCL_MASK) == 0)
-		return MAX14577_REGULATOR_CURRENT_LIMIT_MIN;
+		return limits->min;
 
 	reg_data = ((reg_data & CHGCTRL4_MBCICHWRCH_MASK) >>
 			CHGCTRL4_MBCICHWRCH_SHIFT);
-	return MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_START +
-		reg_data * MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_STEP;
+	return limits->high_start + reg_data * limits->high_step;
 }
 
 static int max14577_reg_set_current_limit(struct regulator_dev *rdev,
@@ -67,33 +105,39 @@ static int max14577_reg_set_current_limit(struct regulator_dev *rdev,
 {
 	int i, current_bits = 0xf;
 	u8 reg_data;
+	struct max14577 *max14577 = rdev_get_drvdata(rdev);
+	const struct maxim_charger_current *limits =
+		&maxim_charger_currents[max14577->dev_type];
 
 	if (rdev_get_id(rdev) != MAX14577_CHARGER)
 		return -EINVAL;
 
-	if (min_uA > MAX14577_REGULATOR_CURRENT_LIMIT_MAX ||
-			max_uA < MAX14577_REGULATOR_CURRENT_LIMIT_MIN)
+	if (min_uA > limits->max || max_uA < limits->min)
 		return -EINVAL;
 
-	if (max_uA < MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_START) {
-		/* Less than 200 mA, so set 90mA (turn only Low Bit off) */
+	if (max_uA < limits->high_start) {
+		/*
+		 * Less than high_start,
+		 * so set the minimal current (turn only Low Bit off)
+		 */
 		u8 reg_data = 0x0 << CHGCTRL4_MBCICHWRCL_SHIFT;
 		return max14577_update_reg(rdev->regmap,
 				MAX14577_CHG_REG_CHG_CTRL4,
 				CHGCTRL4_MBCICHWRCL_MASK, reg_data);
 	}
 
-	/* max_uA is in range: <LIMIT_HIGH_START, inifinite>, so search for
-	 * valid current starting from LIMIT_MAX. */
-	for (i = MAX14577_REGULATOR_CURRENT_LIMIT_MAX;
-			i >= MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_START;
-			i -= MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_STEP) {
+	/*
+	 * max_uA is in range: <high_start, inifinite>, so search for
+	 * valid current starting from maximum current.
+	 */
+	for (i = limits->max; i >= limits->high_start; i -= limits->high_step) {
 		if (i <= max_uA)
 			break;
 		current_bits--;
 	}
 	BUG_ON(current_bits < 0); /* Cannot happen */
-	/* Turn Low Bit on (use range 200mA-950 mA) */
+
+	/* Turn Low Bit on (use range high_start-max)... */
 	reg_data = 0x1 << CHGCTRL4_MBCICHWRCL_SHIFT;
 	/* and set proper High Bits */
 	reg_data |= current_bits << CHGCTRL4_MBCICHWRCH_SHIFT;
@@ -118,7 +162,7 @@ static struct regulator_ops max14577_charger_ops = {
 	.set_current_limit	= max14577_reg_set_current_limit,
 };
 
-static const struct regulator_desc supported_regulators[] = {
+static const struct regulator_desc max14577_supported_regulators[] = {
 	[MAX14577_SAFEOUT] = {
 		.name		= "SAFEOUT",
 		.id		= MAX14577_SAFEOUT,
@@ -141,16 +185,88 @@ static const struct regulator_desc supported_regulators[] = {
 	},
 };
 
+static struct regulator_ops max77836_ldo_ops = {
+	.is_enabled		= regulator_is_enabled_regmap,
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.list_voltage		= regulator_list_voltage_linear,
+	.map_voltage		= regulator_map_voltage_linear,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	/* TODO: add .set_suspend_mode */
+};
+
+static const struct regulator_desc max77836_supported_regulators[] = {
+	[MAX14577_SAFEOUT] = {
+		.name		= "SAFEOUT",
+		.id		= MAX14577_SAFEOUT,
+		.ops		= &max14577_safeout_ops,
+		.type		= REGULATOR_VOLTAGE,
+		.owner		= THIS_MODULE,
+		.n_voltages	= 1,
+		.min_uV		= MAX14577_REGULATOR_SAFEOUT_VOLTAGE,
+		.enable_reg	= MAX14577_REG_CONTROL2,
+		.enable_mask	= CTRL2_SFOUTORD_MASK,
+	},
+	[MAX14577_CHARGER] = {
+		.name		= "CHARGER",
+		.id		= MAX14577_CHARGER,
+		.ops		= &max14577_charger_ops,
+		.type		= REGULATOR_CURRENT,
+		.owner		= THIS_MODULE,
+		.enable_reg	= MAX14577_CHG_REG_CHG_CTRL2,
+		.enable_mask	= CHGCTRL2_MBCHOSTEN_MASK,
+	},
+	[MAX77836_LDO1] = {
+		.name		= "LDO1",
+		.id		= MAX77836_LDO1,
+		.ops		= &max77836_ldo_ops,
+		.type		= REGULATOR_VOLTAGE,
+		.owner		= THIS_MODULE,
+		.n_voltages	= MAX77836_REGULATOR_LDO_VOLTAGE_STEPS_NUM,
+		.min_uV		= MAX77836_REGULATOR_LDO_VOLTAGE_MIN,
+		.uV_step	= MAX77836_REGULATOR_LDO_VOLTAGE_STEP,
+		.enable_reg	= MAX77836_LDO_REG_CNFG1_LDO1,
+		.enable_mask	= MAX77836_CNFG1_LDO_PWRMD_MASK,
+		.vsel_reg	= MAX77836_LDO_REG_CNFG1_LDO1,
+		.vsel_mask	= MAX77836_CNFG1_LDO_TV_MASK,
+	},
+	[MAX77836_LDO2] = {
+		.name		= "LDO2",
+		.id		= MAX77836_LDO2,
+		.ops		= &max77836_ldo_ops,
+		.type		= REGULATOR_VOLTAGE,
+		.owner		= THIS_MODULE,
+		.n_voltages	= MAX77836_REGULATOR_LDO_VOLTAGE_STEPS_NUM,
+		.min_uV		= MAX77836_REGULATOR_LDO_VOLTAGE_MIN,
+		.uV_step	= MAX77836_REGULATOR_LDO_VOLTAGE_STEP,
+		.enable_reg	= MAX77836_LDO_REG_CNFG1_LDO2,
+		.enable_mask	= MAX77836_CNFG1_LDO_PWRMD_MASK,
+		.vsel_reg	= MAX77836_LDO_REG_CNFG1_LDO2,
+		.vsel_mask	= MAX77836_CNFG1_LDO_TV_MASK,
+	},
+};
+
 #ifdef CONFIG_OF
 static struct of_regulator_match max14577_regulator_matches[] = {
 	{ .name	= "SAFEOUT", },
 	{ .name = "CHARGER", },
 };
 
-static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
+static struct of_regulator_match max77836_regulator_matches[] = {
+	{ .name	= "SAFEOUT", },
+	{ .name = "CHARGER", },
+	{ .name = "LDO1", },
+	{ .name = "LDO2", },
+};
+
+static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,
+		enum maxim_device_type dev_type)
 {
 	int ret;
 	struct device_node *np;
+	struct of_regulator_match *regulator_matches;
+	unsigned int regulator_matches_size;
 
 	np = of_get_child_by_name(pdev->dev.parent->of_node, "regulators");
 	if (!np) {
@@ -158,8 +274,19 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	ret = of_regulator_match(&pdev->dev, np, max14577_regulator_matches,
-			MAX14577_REG_MAX);
+	switch (dev_type) {
+	case MAXIM_DEVICE_TYPE_MAX77836:
+		regulator_matches = max77836_regulator_matches;
+		regulator_matches_size = ARRAY_SIZE(max77836_regulator_matches);
+		break;
+	case MAXIM_DEVICE_TYPE_MAX14577:
+	default:
+		regulator_matches = max14577_regulator_matches;
+		regulator_matches_size = ARRAY_SIZE(max14577_regulator_matches);
+	}
+
+	ret = of_regulator_match(&pdev->dev, np, regulator_matches,
+			regulator_matches_size);
 	if (ret < 0)
 		dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
 	else
@@ -170,31 +297,74 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
 	return ret;
 }
 
-static inline struct regulator_init_data *match_init_data(int index)
+static inline struct regulator_init_data *match_init_data(int index,
+		enum maxim_device_type dev_type)
 {
-	return max14577_regulator_matches[index].init_data;
+	switch (dev_type) {
+	case MAXIM_DEVICE_TYPE_MAX77836:
+		return max77836_regulator_matches[index].init_data;
+
+	case MAXIM_DEVICE_TYPE_MAX14577:
+	default:
+		return max14577_regulator_matches[index].init_data;
+	}
 }
 
-static inline struct device_node *match_of_node(int index)
+static inline struct device_node *match_of_node(int index,
+		enum maxim_device_type dev_type)
 {
-	return max14577_regulator_matches[index].of_node;
+	switch (dev_type) {
+	case MAXIM_DEVICE_TYPE_MAX77836:
+		return max77836_regulator_matches[index].of_node;
+
+	case MAXIM_DEVICE_TYPE_MAX14577:
+	default:
+		return max14577_regulator_matches[index].of_node;
+	}
 }
 #else /* CONFIG_OF */
-static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
+static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev,
+		enum maxim_device_type dev_type)
 {
 	return 0;
 }
-static inline struct regulator_init_data *match_init_data(int index)
+static inline struct regulator_init_data *match_init_data(int index,
+		enum maxim_device_type dev_type)
 {
 	return NULL;
 }
 
-static inline struct device_node *match_of_node(int index)
+static inline struct device_node *match_of_node(int index,
+		enum maxim_device_type dev_type)
 {
 	return NULL;
 }
 #endif /* CONFIG_OF */
 
+/**
+ * Registers for regulators of max77836 use different I2C slave addresses so
+ * different regmaps must be used for them.
+ *
+ * Returns proper regmap for accessing regulator passed by id.
+ */
+static struct regmap *max14577_get_regmap(struct max14577 *max14577,
+		int reg_id)
+{
+	switch (max14577->dev_type) {
+	case MAXIM_DEVICE_TYPE_MAX77836:
+		switch (reg_id) {
+		case MAX77836_SAFEOUT ... MAX77836_CHARGER:
+			return max14577->regmap;
+		default:
+			/* MAX77836_LDO1 ... MAX77836_LDO2 */
+			return max14577->regmap_pmic;
+		}
+
+	case MAXIM_DEVICE_TYPE_MAX14577:
+	default:
+		return max14577->regmap;
+	}
+}
 
 static int max14577_regulator_probe(struct platform_device *pdev)
 {
@@ -202,15 +372,29 @@ static int max14577_regulator_probe(struct platform_device *pdev)
 	struct max14577_platform_data *pdata = dev_get_platdata(max14577->dev);
 	int i, ret;
 	struct regulator_config config = {};
+	const struct regulator_desc *supported_regulators;
+	unsigned int supported_regulators_size;
+	enum maxim_device_type dev_type = max14577->dev_type;
 
-	ret = max14577_regulator_dt_parse_pdata(pdev);
+	ret = max14577_regulator_dt_parse_pdata(pdev, dev_type);
 	if (ret)
 		return ret;
 
+	switch (dev_type) {
+	case MAXIM_DEVICE_TYPE_MAX77836:
+		supported_regulators = max77836_supported_regulators;
+		supported_regulators_size = ARRAY_SIZE(max77836_supported_regulators);
+		break;
+	case MAXIM_DEVICE_TYPE_MAX14577:
+	default:
+		supported_regulators = max14577_supported_regulators;
+		supported_regulators_size = ARRAY_SIZE(max14577_supported_regulators);
+	}
+
 	config.dev = &pdev->dev;
-	config.regmap = max14577->regmap;
+	config.driver_data = max14577;
 
-	for (i = 0; i < ARRAY_SIZE(supported_regulators); i++) {
+	for (i = 0; i < supported_regulators_size; i++) {
 		struct regulator_dev *regulator;
 		/*
 		 * Index of supported_regulators[] is also the id and must
@@ -220,17 +404,19 @@ static int max14577_regulator_probe(struct platform_device *pdev)
 			config.init_data = pdata->regulators[i].initdata;
 			config.of_node = pdata->regulators[i].of_node;
 		} else {
-			config.init_data = match_init_data(i);
-			config.of_node = match_of_node(i);
+			config.init_data = match_init_data(i, dev_type);
+			config.of_node = match_of_node(i, dev_type);
 		}
+		config.regmap = max14577_get_regmap(max14577,
+				supported_regulators[i].id);
 
 		regulator = devm_regulator_register(&pdev->dev,
 				&supported_regulators[i], &config);
 		if (IS_ERR(regulator)) {
 			ret = PTR_ERR(regulator);
 			dev_err(&pdev->dev,
-					"Regulator init failed for ID %d with error: %d\n",
-					i, ret);
+					"Regulator init failed for %d/%s with error: %d\n",
+					i, supported_regulators[i].name, ret);
 			return ret;
 		}
 	}
@@ -238,20 +424,41 @@ static int max14577_regulator_probe(struct platform_device *pdev)
 	return ret;
 }
 
+static const struct platform_device_id max14577_regulator_id[] = {
+	{ "max14577-regulator", MAXIM_DEVICE_TYPE_MAX14577, },
+	{ "max77836-regulator", MAXIM_DEVICE_TYPE_MAX77836, },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, max14577_regulator_id);
+
 static struct platform_driver max14577_regulator_driver = {
 	.driver = {
 		   .owner = THIS_MODULE,
 		   .name = "max14577-regulator",
 		   },
-	.probe	= max14577_regulator_probe,
+	.probe		= max14577_regulator_probe,
+	.id_table	= max14577_regulator_id,
 };
 
 static int __init max14577_regulator_init(void)
 {
+	/* Check for valid values for charger */
 	BUILD_BUG_ON(MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_START +
 			MAX14577_REGULATOR_CURRENT_LIMIT_HIGH_STEP * 0xf !=
 			MAX14577_REGULATOR_CURRENT_LIMIT_MAX);
-	BUILD_BUG_ON(ARRAY_SIZE(supported_regulators) != MAX14577_REG_MAX);
+	BUILD_BUG_ON(MAX77836_REGULATOR_CURRENT_LIMIT_HIGH_START +
+			MAX77836_REGULATOR_CURRENT_LIMIT_HIGH_STEP * 0xf !=
+			MAX77836_REGULATOR_CURRENT_LIMIT_MAX);
+	/* Valid charger current values must be provided for each chipset */
+	BUILD_BUG_ON(ARRAY_SIZE(maxim_charger_currents) != MAXIM_DEVICE_TYPE_NUM);
+
+	BUILD_BUG_ON(ARRAY_SIZE(max14577_supported_regulators) != MAX14577_REGULATOR_NUM);
+	BUILD_BUG_ON(ARRAY_SIZE(max77836_supported_regulators) != MAX77836_REGULATOR_NUM);
+
+	BUILD_BUG_ON(MAX77836_REGULATOR_LDO_VOLTAGE_MIN +
+			(MAX77836_REGULATOR_LDO_VOLTAGE_STEP *
+			  (MAX77836_REGULATOR_LDO_VOLTAGE_STEPS_NUM - 1)) !=
+			MAX77836_REGULATOR_LDO_VOLTAGE_MAX);
 
 	return platform_driver_register(&max14577_regulator_driver);
 }
@@ -264,6 +471,6 @@ static void __exit max14577_regulator_exit(void)
 module_exit(max14577_regulator_exit);
 
 MODULE_AUTHOR("Krzysztof Kozlowski <k.kozlowski@samsung.com>");
-MODULE_DESCRIPTION("MAXIM 14577 regulator driver");
+MODULE_DESCRIPTION("Maxim 14577/77836 regulator driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:max14577-regulator");