power: supply: max77650: Add support for battery charger

Add basic support for the battery charger for max77650 PMIC.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

3 files changed, 376 insertions, 0 deletions

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index e901b9879e7e..0230c96fa94d 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -499,6 +499,13 @@ config CHARGER_DETECTOR_MAX14656
 	  Revision 1.2 and can be found e.g. in Kindle 4/5th generation
 	  readers and certain LG devices.
 
+config CHARGER_MAX77650
+	tristate "Maxim MAX77650 battery charger driver"
+	depends on MFD_MAX77650
+	help
+	  Say Y to enable support for the battery charger control of MAX77650
+	  PMICs.
+
 config CHARGER_MAX77693
 	tristate "Maxim MAX77693 battery charger driver"
 	depends on MFD_MAX77693
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index b731c2a9b695..b73eb8c5c1a9 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -70,6 +70,7 @@ obj-$(CONFIG_CHARGER_MANAGER)	+= charger-manager.o
 obj-$(CONFIG_CHARGER_LTC3651)	+= ltc3651-charger.o
 obj-$(CONFIG_CHARGER_MAX14577)	+= max14577_charger.o
 obj-$(CONFIG_CHARGER_DETECTOR_MAX14656)	+= max14656_charger_detector.o
+obj-$(CONFIG_CHARGER_MAX77650)	+= max77650-charger.o
 obj-$(CONFIG_CHARGER_MAX77693)	+= max77693_charger.o
 obj-$(CONFIG_CHARGER_MAX8997)	+= max8997_charger.o
 obj-$(CONFIG_CHARGER_MAX8998)	+= max8998_charger.o
diff --git a/drivers/power/supply/max77650-charger.c b/drivers/power/supply/max77650-charger.c
new file mode 100644
index 000000000000..e34714cb05ec
--- /dev/null
+++ b/drivers/power/supply/max77650-charger.c
@@ -0,0 +1,368 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (C) 2018 BayLibre SAS
+// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
+//
+// Battery charger driver for MAXIM 77650/77651 charger/power-supply.
+
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/max77650.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/regmap.h>
+
+#define MAX77650_CHARGER_ENABLED		BIT(0)
+#define MAX77650_CHARGER_DISABLED		0x00
+#define MAX77650_CHARGER_CHG_EN_MASK		BIT(0)
+
+#define MAX77650_CHG_DETAILS_MASK		GENMASK(7, 4)
+#define MAX77650_CHG_DETAILS_BITS(_reg) \
+		(((_reg) & MAX77650_CHG_DETAILS_MASK) >> 4)
+
+/* Charger is OFF. */
+#define MAX77650_CHG_OFF			0x00
+/* Charger is in prequalification mode. */
+#define MAX77650_CHG_PREQ			0x01
+/* Charger is in fast-charge constant current mode. */
+#define MAX77650_CHG_ON_CURR			0x02
+/* Charger is in JEITA modified fast-charge constant-current mode. */
+#define MAX77650_CHG_ON_CURR_JEITA		0x03
+/* Charger is in fast-charge constant-voltage mode. */
+#define MAX77650_CHG_ON_VOLT			0x04
+/* Charger is in JEITA modified fast-charge constant-voltage mode. */
+#define MAX77650_CHG_ON_VOLT_JEITA		0x05
+/* Charger is in top-off mode. */
+#define MAX77650_CHG_ON_TOPOFF			0x06
+/* Charger is in JEITA modified top-off mode. */
+#define MAX77650_CHG_ON_TOPOFF_JEITA		0x07
+/* Charger is done. */
+#define MAX77650_CHG_DONE			0x08
+/* Charger is JEITA modified done. */
+#define MAX77650_CHG_DONE_JEITA			0x09
+/* Charger is suspended due to a prequalification timer fault. */
+#define MAX77650_CHG_SUSP_PREQ_TIM_FAULT	0x0a
+/* Charger is suspended due to a fast-charge timer fault. */
+#define MAX77650_CHG_SUSP_FAST_CHG_TIM_FAULT	0x0b
+/* Charger is suspended due to a battery temperature fault. */
+#define MAX77650_CHG_SUSP_BATT_TEMP_FAULT	0x0c
+
+#define MAX77650_CHGIN_DETAILS_MASK		GENMASK(3, 2)
+#define MAX77650_CHGIN_DETAILS_BITS(_reg) \
+		(((_reg) & MAX77650_CHGIN_DETAILS_MASK) >> 2)
+
+#define MAX77650_CHGIN_UNDERVOLTAGE_LOCKOUT	0x00
+#define MAX77650_CHGIN_OVERVOLTAGE_LOCKOUT	0x01
+#define MAX77650_CHGIN_OKAY			0x11
+
+#define MAX77650_CHARGER_CHG_MASK	BIT(1)
+#define MAX77650_CHARGER_CHG_CHARGING(_reg) \
+		(((_reg) & MAX77650_CHARGER_CHG_MASK) > 1)
+
+#define MAX77650_CHARGER_VCHGIN_MIN_MASK	0xc0
+#define MAX77650_CHARGER_VCHGIN_MIN_SHIFT(_val)	((_val) << 5)
+
+#define MAX77650_CHARGER_ICHGIN_LIM_MASK	0x1c
+#define MAX77650_CHARGER_ICHGIN_LIM_SHIFT(_val)	((_val) << 2)
+
+struct max77650_charger_data {
+	struct regmap *map;
+	struct device *dev;
+};
+
+static enum power_supply_property max77650_charger_properties[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_ONLINE,
+	POWER_SUPPLY_PROP_CHARGE_TYPE
+};
+
+static const unsigned int max77650_charger_vchgin_min_table[] = {
+	4000000, 4100000, 4200000, 4300000, 4400000, 4500000, 4600000, 4700000
+};
+
+static const unsigned int max77650_charger_ichgin_lim_table[] = {
+	95000, 190000, 285000, 380000, 475000
+};
+
+static int max77650_charger_set_vchgin_min(struct max77650_charger_data *chg,
+					   unsigned int val)
+{
+	int i, rv;
+
+	for (i = 0; i < ARRAY_SIZE(max77650_charger_vchgin_min_table); i++) {
+		if (val == max77650_charger_vchgin_min_table[i]) {
+			rv = regmap_update_bits(chg->map,
+					MAX77650_REG_CNFG_CHG_B,
+					MAX77650_CHARGER_VCHGIN_MIN_MASK,
+					MAX77650_CHARGER_VCHGIN_MIN_SHIFT(i));
+			if (rv)
+				return rv;
+
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int max77650_charger_set_ichgin_lim(struct max77650_charger_data *chg,
+					   unsigned int val)
+{
+	int i, rv;
+
+	for (i = 0; i < ARRAY_SIZE(max77650_charger_ichgin_lim_table); i++) {
+		if (val == max77650_charger_ichgin_lim_table[i]) {
+			rv = regmap_update_bits(chg->map,
+					MAX77650_REG_CNFG_CHG_B,
+					MAX77650_CHARGER_ICHGIN_LIM_MASK,
+					MAX77650_CHARGER_ICHGIN_LIM_SHIFT(i));
+			if (rv)
+				return rv;
+
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int max77650_charger_enable(struct max77650_charger_data *chg)
+{
+	int rv;
+
+	rv = regmap_update_bits(chg->map,
+				MAX77650_REG_CNFG_CHG_B,
+				MAX77650_CHARGER_CHG_EN_MASK,
+				MAX77650_CHARGER_ENABLED);
+	if (rv)
+		dev_err(chg->dev, "unable to enable the charger: %d\n", rv);
+
+	return rv;
+}
+
+static int max77650_charger_disable(struct max77650_charger_data *chg)
+{
+	int rv;
+
+	rv = regmap_update_bits(chg->map,
+				MAX77650_REG_CNFG_CHG_B,
+				MAX77650_CHARGER_CHG_EN_MASK,
+				MAX77650_CHARGER_DISABLED);
+	if (rv)
+		dev_err(chg->dev, "unable to disable the charger: %d\n", rv);
+
+	return rv;
+}
+
+static irqreturn_t max77650_charger_check_status(int irq, void *data)
+{
+	struct max77650_charger_data *chg = data;
+	int rv, reg;
+
+	rv = regmap_read(chg->map, MAX77650_REG_STAT_CHG_B, &reg);
+	if (rv) {
+		dev_err(chg->dev,
+			"unable to read the charger status: %d\n", rv);
+		return IRQ_HANDLED;
+	}
+
+	switch (MAX77650_CHGIN_DETAILS_BITS(reg)) {
+	case MAX77650_CHGIN_UNDERVOLTAGE_LOCKOUT:
+		dev_err(chg->dev, "undervoltage lockout detected, disabling charger\n");
+		max77650_charger_disable(chg);
+		break;
+	case MAX77650_CHGIN_OVERVOLTAGE_LOCKOUT:
+		dev_err(chg->dev, "overvoltage lockout detected, disabling charger\n");
+		max77650_charger_disable(chg);
+		break;
+	case MAX77650_CHGIN_OKAY:
+		max77650_charger_enable(chg);
+		break;
+	default:
+		/* May be 0x10 - debouncing */
+		break;
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int max77650_charger_get_property(struct power_supply *psy,
+					 enum power_supply_property psp,
+					 union power_supply_propval *val)
+{
+	struct max77650_charger_data *chg = power_supply_get_drvdata(psy);
+	int rv, reg;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		rv = regmap_read(chg->map, MAX77650_REG_STAT_CHG_B, &reg);
+		if (rv)
+			return rv;
+
+		if (MAX77650_CHARGER_CHG_CHARGING(reg)) {
+			val->intval = POWER_SUPPLY_STATUS_CHARGING;
+			break;
+		}
+
+		switch (MAX77650_CHG_DETAILS_BITS(reg)) {
+		case MAX77650_CHG_OFF:
+		case MAX77650_CHG_SUSP_PREQ_TIM_FAULT:
+		case MAX77650_CHG_SUSP_FAST_CHG_TIM_FAULT:
+		case MAX77650_CHG_SUSP_BATT_TEMP_FAULT:
+			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+			break;
+		case MAX77650_CHG_PREQ:
+		case MAX77650_CHG_ON_CURR:
+		case MAX77650_CHG_ON_CURR_JEITA:
+		case MAX77650_CHG_ON_VOLT:
+		case MAX77650_CHG_ON_VOLT_JEITA:
+		case MAX77650_CHG_ON_TOPOFF:
+		case MAX77650_CHG_ON_TOPOFF_JEITA:
+			val->intval = POWER_SUPPLY_STATUS_CHARGING;
+			break;
+		case MAX77650_CHG_DONE:
+			val->intval = POWER_SUPPLY_STATUS_FULL;
+			break;
+		default:
+			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
+		}
+		break;
+	case POWER_SUPPLY_PROP_ONLINE:
+		rv = regmap_read(chg->map, MAX77650_REG_STAT_CHG_B, &reg);
+		if (rv)
+			return rv;
+
+		val->intval = MAX77650_CHARGER_CHG_CHARGING(reg);
+		break;
+	case POWER_SUPPLY_PROP_CHARGE_TYPE:
+		rv = regmap_read(chg->map, MAX77650_REG_STAT_CHG_B, &reg);
+		if (rv)
+			return rv;
+
+		if (!MAX77650_CHARGER_CHG_CHARGING(reg)) {
+			val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
+			break;
+		}
+
+		switch (MAX77650_CHG_DETAILS_BITS(reg)) {
+		case MAX77650_CHG_PREQ:
+		case MAX77650_CHG_ON_CURR:
+		case MAX77650_CHG_ON_CURR_JEITA:
+		case MAX77650_CHG_ON_VOLT:
+		case MAX77650_CHG_ON_VOLT_JEITA:
+			val->intval = POWER_SUPPLY_CHARGE_TYPE_FAST;
+			break;
+		case MAX77650_CHG_ON_TOPOFF:
+		case MAX77650_CHG_ON_TOPOFF_JEITA:
+			val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
+			break;
+		default:
+			val->intval = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static const struct power_supply_desc max77650_battery_desc = {
+	.name		= "max77650",
+	.type		= POWER_SUPPLY_TYPE_USB,
+	.get_property	= max77650_charger_get_property,
+	.properties	= max77650_charger_properties,
+	.num_properties	= ARRAY_SIZE(max77650_charger_properties),
+};
+
+static int max77650_charger_probe(struct platform_device *pdev)
+{
+	struct power_supply_config pscfg = {};
+	struct max77650_charger_data *chg;
+	struct power_supply *battery;
+	struct device *dev, *parent;
+	int rv, chg_irq, chgin_irq;
+	unsigned int prop;
+
+	dev = &pdev->dev;
+	parent = dev->parent;
+
+	chg = devm_kzalloc(dev, sizeof(*chg), GFP_KERNEL);
+	if (!chg)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, chg);
+
+	chg->map = dev_get_regmap(parent, NULL);
+	if (!chg->map)
+		return -ENODEV;
+
+	chg->dev = dev;
+
+	pscfg.of_node = dev->of_node;
+	pscfg.drv_data = chg;
+
+	chg_irq = platform_get_irq_byname(pdev, "CHG");
+	if (chg_irq < 0)
+		return chg_irq;
+
+	chgin_irq = platform_get_irq_byname(pdev, "CHGIN");
+	if (chgin_irq < 0)
+		return chgin_irq;
+
+	rv = devm_request_any_context_irq(dev, chg_irq,
+					  max77650_charger_check_status,
+					  IRQF_ONESHOT, "chg", chg);
+	if (rv < 0)
+		return rv;
+
+	rv = devm_request_any_context_irq(dev, chgin_irq,
+					  max77650_charger_check_status,
+					  IRQF_ONESHOT, "chgin", chg);
+	if (rv < 0)
+		return rv;
+
+	battery = devm_power_supply_register(dev,
+					     &max77650_battery_desc, &pscfg);
+	if (IS_ERR(battery))
+		return PTR_ERR(battery);
+
+	rv = of_property_read_u32(dev->of_node,
+				  "input-voltage-min-microvolt", &prop);
+	if (rv == 0) {
+		rv = max77650_charger_set_vchgin_min(chg, prop);
+		if (rv)
+			return rv;
+	}
+
+	rv = of_property_read_u32(dev->of_node,
+				  "input-current-limit-microamp", &prop);
+	if (rv == 0) {
+		rv = max77650_charger_set_ichgin_lim(chg, prop);
+		if (rv)
+			return rv;
+	}
+
+	return max77650_charger_enable(chg);
+}
+
+static int max77650_charger_remove(struct platform_device *pdev)
+{
+	struct max77650_charger_data *chg = platform_get_drvdata(pdev);
+
+	return max77650_charger_disable(chg);
+}
+
+static struct platform_driver max77650_charger_driver = {
+	.driver = {
+		.name = "max77650-charger",
+	},
+	.probe = max77650_charger_probe,
+	.remove = max77650_charger_remove,
+};
+module_platform_driver(max77650_charger_driver);
+
+MODULE_DESCRIPTION("MAXIM 77650/77651 charger driver");
+MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
+MODULE_LICENSE("GPL v2");