1 files changed, 278 insertions, 150 deletions

diff --git a/drivers/power/supply/gpio-charger.c b/drivers/power/supply/gpio-charger.c
index 001731e88718..2504190eba82 100644
--- a/drivers/power/supply/gpio-charger.c
+++ b/drivers/power/supply/gpio-charger.c
@@ -1,20 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
  *  Driver for chargers which report their online status through a GPIO pin
- *
- *  This program is free software; you can redistribute it and/or modify it
- *  under  the terms of the GNU General  Public License as published by the
- *  Free Software Foundation;  either version 2 of the License, or (at your
- *  option) any later version.
- *
- *  You should have received a copy of the GNU General Public License along
- *  with this program; if not, write to the Free Software Foundation, Inc.,
- *  675 Mass Ave, Cambridge, MA 02139, USA.
- *
  */
 
 #include <linux/device.h>
-#include <linux/gpio.h> /* For legacy platform data */
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
@@ -27,15 +17,26 @@
 
 #include <linux/power/gpio-charger.h>
 
+struct gpio_mapping {
+	u32 limit_ua;
+	u32 gpiodata;
+} __packed;
+
 struct gpio_charger {
-	const struct gpio_charger_platform_data *pdata;
+	struct device *dev;
 	unsigned int irq;
+	unsigned int charge_status_irq;
 	bool wakeup_enabled;
 
 	struct power_supply *charger;
 	struct power_supply_desc charger_desc;
 	struct gpio_desc *gpiod;
-	bool legacy_gpio_requested;
+	struct gpio_desc *charge_status;
+
+	struct gpio_descs *current_limit_gpios;
+	struct gpio_mapping *current_limit_map;
+	u32 current_limit_map_size;
+	u32 charge_current_limit;
 };
 
 static irqreturn_t gpio_charger_irq(int irq, void *devid)
@@ -52,17 +53,61 @@ static inline struct gpio_charger *psy_to_gpio_charger(struct power_supply *psy)
 	return power_supply_get_drvdata(psy);
 }
 
+static int set_charge_current_limit(struct gpio_charger *gpio_charger, int val)
+{
+	struct gpio_mapping mapping;
+	int ndescs = gpio_charger->current_limit_gpios->ndescs;
+	struct gpio_desc **gpios = gpio_charger->current_limit_gpios->desc;
+	int i;
+
+	if (!gpio_charger->current_limit_map_size)
+		return -EINVAL;
+
+	for (i = 0; i < gpio_charger->current_limit_map_size; i++) {
+		if (gpio_charger->current_limit_map[i].limit_ua <= val)
+			break;
+	}
+
+	/*
+	 * If a valid charge current limit isn't found, default to smallest
+	 * current limitation for safety reasons.
+	 */
+	if (i >= gpio_charger->current_limit_map_size)
+		i = gpio_charger->current_limit_map_size - 1;
+
+	mapping = gpio_charger->current_limit_map[i];
+
+	for (i = 0; i < ndescs; i++) {
+		bool val = (mapping.gpiodata >> i) & 1;
+
+		gpiod_set_value_cansleep(gpios[ndescs - i - 1], val);
+	}
+
+	gpio_charger->charge_current_limit = mapping.limit_ua;
+
+	dev_dbg(gpio_charger->dev, "set charge current limit to %d (requested: %d)\n",
+		gpio_charger->charge_current_limit, val);
+
+	return 0;
+}
+
 static int gpio_charger_get_property(struct power_supply *psy,
 		enum power_supply_property psp, union power_supply_propval *val)
 {
 	struct gpio_charger *gpio_charger = psy_to_gpio_charger(psy);
-	const struct gpio_charger_platform_data *pdata = gpio_charger->pdata;
 
 	switch (psp) {
 	case POWER_SUPPLY_PROP_ONLINE:
 		val->intval = gpiod_get_value_cansleep(gpio_charger->gpiod);
-		/* This xor is only ever used with legacy pdata GPIO */
-		val->intval ^= pdata->gpio_active_low;
+		break;
+	case POWER_SUPPLY_PROP_STATUS:
+		if (gpiod_get_value_cansleep(gpio_charger->charge_status))
+			val->intval = POWER_SUPPLY_STATUS_CHARGING;
+		else
+			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		break;
+	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
+		val->intval = gpio_charger->charge_current_limit;
 		break;
 	default:
 		return -EINVAL;
@@ -71,175 +116,260 @@ static int gpio_charger_get_property(struct power_supply *psy,
 	return 0;
 }
 
-static enum power_supply_property gpio_charger_properties[] = {
-	POWER_SUPPLY_PROP_ONLINE,
-};
+static int gpio_charger_set_property(struct power_supply *psy,
+	enum power_supply_property psp, const union power_supply_propval *val)
+{
+	struct gpio_charger *gpio_charger = psy_to_gpio_charger(psy);
 
-static
-struct gpio_charger_platform_data *gpio_charger_parse_dt(struct device *dev)
+	switch (psp) {
+	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
+		return set_charge_current_limit(gpio_charger, val->intval);
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int gpio_charger_property_is_writeable(struct power_supply *psy,
+					      enum power_supply_property psp)
+{
+	switch (psp) {
+	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
+		return 1;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static enum power_supply_type gpio_charger_get_type(struct device *dev)
 {
-	struct device_node *np = dev->of_node;
-	struct gpio_charger_platform_data *pdata;
 	const char *chargetype;
-	int ret;
 
-	if (!np)
-		return ERR_PTR(-ENOENT);
-
-	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
-	if (!pdata)
-		return ERR_PTR(-ENOMEM);
-
-	pdata->name = np->name;
-	pdata->type = POWER_SUPPLY_TYPE_UNKNOWN;
-	ret = of_property_read_string(np, "charger-type", &chargetype);
-	if (ret >= 0) {
-		if (!strncmp("unknown", chargetype, 7))
-			pdata->type = POWER_SUPPLY_TYPE_UNKNOWN;
-		else if (!strncmp("battery", chargetype, 7))
-			pdata->type = POWER_SUPPLY_TYPE_BATTERY;
-		else if (!strncmp("ups", chargetype, 3))
-			pdata->type = POWER_SUPPLY_TYPE_UPS;
-		else if (!strncmp("mains", chargetype, 5))
-			pdata->type = POWER_SUPPLY_TYPE_MAINS;
-		else if (!strncmp("usb-sdp", chargetype, 7))
-			pdata->type = POWER_SUPPLY_TYPE_USB;
-		else if (!strncmp("usb-dcp", chargetype, 7))
-			pdata->type = POWER_SUPPLY_TYPE_USB_DCP;
-		else if (!strncmp("usb-cdp", chargetype, 7))
-			pdata->type = POWER_SUPPLY_TYPE_USB_CDP;
-		else if (!strncmp("usb-aca", chargetype, 7))
-			pdata->type = POWER_SUPPLY_TYPE_USB_ACA;
-		else
-			dev_warn(dev, "unknown charger type %s\n", chargetype);
+	if (!device_property_read_string(dev, "charger-type", &chargetype)) {
+		if (!strcmp("unknown", chargetype))
+			return POWER_SUPPLY_TYPE_UNKNOWN;
+		if (!strcmp("battery", chargetype))
+			return POWER_SUPPLY_TYPE_BATTERY;
+		if (!strcmp("ups", chargetype))
+			return POWER_SUPPLY_TYPE_UPS;
+		if (!strcmp("mains", chargetype))
+			return POWER_SUPPLY_TYPE_MAINS;
+		if (!strcmp("usb-sdp", chargetype))
+			return POWER_SUPPLY_TYPE_USB;
+		if (!strcmp("usb-dcp", chargetype))
+			return POWER_SUPPLY_TYPE_USB;
+		if (!strcmp("usb-cdp", chargetype))
+			return POWER_SUPPLY_TYPE_USB;
+		if (!strcmp("usb-aca", chargetype))
+			return POWER_SUPPLY_TYPE_USB;
+	}
+	dev_warn(dev, "unknown charger type %s\n", chargetype);
+
+	return POWER_SUPPLY_TYPE_UNKNOWN;
+}
+
+static int gpio_charger_get_irq(struct device *dev, void *dev_id,
+				struct gpio_desc *gpio)
+{
+	int ret, irq = gpiod_to_irq(gpio);
+
+	if (irq > 0) {
+		ret = devm_request_any_context_irq(dev, irq, gpio_charger_irq,
+						   IRQF_TRIGGER_RISING |
+						   IRQF_TRIGGER_FALLING,
+						   dev_name(dev),
+						   dev_id);
+		if (ret < 0) {
+			dev_warn(dev, "Failed to request irq: %d\n", ret);
+			irq = 0;
+		}
 	}
 
-	return pdata;
+	return irq;
 }
 
+static int init_charge_current_limit(struct device *dev,
+				    struct gpio_charger *gpio_charger)
+{
+	int i, len;
+	u32 cur_limit = U32_MAX;
+	bool set_def_limit;
+	u32 def_limit;
+
+	gpio_charger->current_limit_gpios = devm_gpiod_get_array_optional(dev,
+		"charge-current-limit", GPIOD_OUT_LOW);
+	if (IS_ERR(gpio_charger->current_limit_gpios)) {
+		dev_err(dev, "error getting current-limit GPIOs\n");
+		return PTR_ERR(gpio_charger->current_limit_gpios);
+	}
+
+	if (!gpio_charger->current_limit_gpios)
+		return 0;
+
+	len = device_property_read_u32_array(dev, "charge-current-limit-mapping",
+		NULL, 0);
+	if (len < 0)
+		return len;
+
+	if (len == 0 || len % 2) {
+		dev_err(dev, "invalid charge-current-limit-mapping length\n");
+		return -EINVAL;
+	}
+
+	gpio_charger->current_limit_map = devm_kmalloc_array(dev,
+		len / 2, sizeof(*gpio_charger->current_limit_map), GFP_KERNEL);
+	if (!gpio_charger->current_limit_map)
+		return -ENOMEM;
+
+	gpio_charger->current_limit_map_size = len / 2;
+
+	len = device_property_read_u32_array(dev, "charge-current-limit-mapping",
+		(u32 *) gpio_charger->current_limit_map, len);
+	if (len < 0)
+		return len;
+
+	set_def_limit = !device_property_read_u32(dev,
+						  "charge-current-limit-default-microamp",
+						  &def_limit);
+	for (i = 0; i < gpio_charger->current_limit_map_size; i++) {
+		if (gpio_charger->current_limit_map[i].limit_ua > cur_limit) {
+			dev_err(dev, "charge-current-limit-mapping not sorted by current in descending order\n");
+			return -EINVAL;
+		}
+
+		cur_limit = gpio_charger->current_limit_map[i].limit_ua;
+		if (set_def_limit && def_limit == cur_limit) {
+			set_charge_current_limit(gpio_charger, cur_limit);
+			return 0;
+		}
+	}
+
+	if (set_def_limit)
+		dev_warn(dev, "charge-current-limit-default-microamp %u not listed in charge-current-limit-mapping\n",
+			 def_limit);
+
+	/* default to smallest current limitation for safety reasons */
+	len = gpio_charger->current_limit_map_size - 1;
+	set_charge_current_limit(gpio_charger,
+		gpio_charger->current_limit_map[len].limit_ua);
+
+	return 0;
+}
+
+/*
+ * The entries will be overwritten by driver's probe routine depending
+ * on the available features. This list ensures, that the array is big
+ * enough for all optional features.
+ */
+static enum power_supply_property gpio_charger_properties[] = {
+	POWER_SUPPLY_PROP_ONLINE,
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
+};
+
 static int gpio_charger_probe(struct platform_device *pdev)
 {
-	const struct gpio_charger_platform_data *pdata = pdev->dev.platform_data;
+	struct device *dev = &pdev->dev;
+	const struct gpio_charger_platform_data *pdata = dev->platform_data;
 	struct power_supply_config psy_cfg = {};
 	struct gpio_charger *gpio_charger;
 	struct power_supply_desc *charger_desc;
+	struct gpio_desc *charge_status;
+	int charge_status_irq;
 	int ret;
-	int irq;
-
-	if (!pdata) {
-		pdata = gpio_charger_parse_dt(&pdev->dev);
-		if (IS_ERR(pdata)) {
-			ret = PTR_ERR(pdata);
-			if (ret != -EPROBE_DEFER)
-				dev_err(&pdev->dev, "No platform data\n");
-			return ret;
-		}
+	int num_props = 0;
+
+	if (!pdata && !dev->of_node) {
+		dev_err(dev, "No platform data\n");
+		return -ENOENT;
 	}
 
-	gpio_charger = devm_kzalloc(&pdev->dev, sizeof(*gpio_charger),
-					GFP_KERNEL);
-	if (!gpio_charger) {
-		dev_err(&pdev->dev, "Failed to alloc driver structure\n");
+	gpio_charger = devm_kzalloc(dev, sizeof(*gpio_charger), GFP_KERNEL);
+	if (!gpio_charger)
 		return -ENOMEM;
-	}
+	gpio_charger->dev = dev;
 
 	/*
 	 * This will fetch a GPIO descriptor from device tree, ACPI or
 	 * boardfile descriptor tables. It's good to try this first.
 	 */
-	gpio_charger->gpiod = devm_gpiod_get(&pdev->dev, NULL, GPIOD_IN);
-
-	/*
-	 * If this fails and we're not using device tree, try the
-	 * legacy platform data method.
-	 */
-	if (IS_ERR(gpio_charger->gpiod) && !pdev->dev.of_node) {
-		/* Non-DT: use legacy GPIO numbers */
-		if (!gpio_is_valid(pdata->gpio)) {
-			dev_err(&pdev->dev, "Invalid gpio pin in pdata\n");
-			return -EINVAL;
-		}
-		ret = gpio_request(pdata->gpio, dev_name(&pdev->dev));
-		if (ret) {
-			dev_err(&pdev->dev, "Failed to request gpio pin: %d\n",
-				ret);
-			return ret;
-		}
-		gpio_charger->legacy_gpio_requested = true;
-		ret = gpio_direction_input(pdata->gpio);
-		if (ret) {
-			dev_err(&pdev->dev, "Failed to set gpio to input: %d\n",
-				ret);
-			goto err_gpio_free;
-		}
-		/* Then convert this to gpiod for now */
-		gpio_charger->gpiod = gpio_to_desc(pdata->gpio);
-	} else if (IS_ERR(gpio_charger->gpiod)) {
+	gpio_charger->gpiod = devm_gpiod_get_optional(dev, NULL, GPIOD_IN);
+	if (IS_ERR(gpio_charger->gpiod)) {
 		/* Just try again if this happens */
-		if (PTR_ERR(gpio_charger->gpiod) == -EPROBE_DEFER)
-			return -EPROBE_DEFER;
-		dev_err(&pdev->dev, "error getting GPIO descriptor\n");
-		return PTR_ERR(gpio_charger->gpiod);
+		return dev_err_probe(dev, PTR_ERR(gpio_charger->gpiod),
+				     "error getting GPIO descriptor\n");
 	}
 
-	charger_desc = &gpio_charger->charger_desc;
+	if (gpio_charger->gpiod) {
+		gpio_charger_properties[num_props] = POWER_SUPPLY_PROP_ONLINE;
+		num_props++;
+	}
 
-	charger_desc->name = pdata->name ? pdata->name : "gpio-charger";
-	charger_desc->type = pdata->type;
+	charge_status = devm_gpiod_get_optional(dev, "charge-status", GPIOD_IN);
+	if (IS_ERR(charge_status))
+		return PTR_ERR(charge_status);
+	if (charge_status) {
+		gpio_charger->charge_status = charge_status;
+		gpio_charger_properties[num_props] = POWER_SUPPLY_PROP_STATUS;
+		num_props++;
+	}
+
+	ret = init_charge_current_limit(dev, gpio_charger);
+	if (ret < 0)
+		return ret;
+	if (gpio_charger->current_limit_map) {
+		gpio_charger_properties[num_props] =
+			POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX;
+		num_props++;
+	}
+
+	charger_desc = &gpio_charger->charger_desc;
 	charger_desc->properties = gpio_charger_properties;
-	charger_desc->num_properties = ARRAY_SIZE(gpio_charger_properties);
+	charger_desc->num_properties = num_props;
 	charger_desc->get_property = gpio_charger_get_property;
+	charger_desc->set_property = gpio_charger_set_property;
+	charger_desc->property_is_writeable =
+					gpio_charger_property_is_writeable;
 
-	psy_cfg.supplied_to = pdata->supplied_to;
-	psy_cfg.num_supplicants = pdata->num_supplicants;
-	psy_cfg.of_node = pdev->dev.of_node;
+	psy_cfg.fwnode = dev_fwnode(dev);
 	psy_cfg.drv_data = gpio_charger;
 
-	gpio_charger->pdata = pdata;
+	if (pdata) {
+		charger_desc->name = pdata->name;
+		charger_desc->type = pdata->type;
+		psy_cfg.supplied_to = pdata->supplied_to;
+		psy_cfg.num_supplicants = pdata->num_supplicants;
+	} else {
+		charger_desc->name = dev->of_node->name;
+		charger_desc->type = gpio_charger_get_type(dev);
+	}
+
+	if (!charger_desc->name)
+		charger_desc->name = pdev->name;
 
-	gpio_charger->charger = power_supply_register(&pdev->dev,
-						      charger_desc, &psy_cfg);
+	gpio_charger->charger = devm_power_supply_register(dev, charger_desc,
+							   &psy_cfg);
 	if (IS_ERR(gpio_charger->charger)) {
 		ret = PTR_ERR(gpio_charger->charger);
-		dev_err(&pdev->dev, "Failed to register power supply: %d\n",
-			ret);
-		goto err_gpio_free;
+		dev_err(dev, "Failed to register power supply: %d\n", ret);
+		return ret;
 	}
 
-	irq = gpiod_to_irq(gpio_charger->gpiod);
-	if (irq > 0) {
-		ret = request_any_context_irq(irq, gpio_charger_irq,
-				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
-				dev_name(&pdev->dev), gpio_charger->charger);
-		if (ret < 0)
-			dev_warn(&pdev->dev, "Failed to request irq: %d\n", ret);
-		else
-			gpio_charger->irq = irq;
-	}
-
-	platform_set_drvdata(pdev, gpio_charger);
-
-	device_init_wakeup(&pdev->dev, 1);
-
-	return 0;
-
-err_gpio_free:
-	if (gpio_charger->legacy_gpio_requested)
-		gpio_free(pdata->gpio);
-	return ret;
-}
+	gpio_charger->irq = gpio_charger_get_irq(dev, gpio_charger->charger,
+						 gpio_charger->gpiod);
 
-static int gpio_charger_remove(struct platform_device *pdev)
-{
-	struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);
+	charge_status_irq = gpio_charger_get_irq(dev, gpio_charger->charger,
+						 gpio_charger->charge_status);
+	gpio_charger->charge_status_irq = charge_status_irq;
 
-	if (gpio_charger->irq)
-		free_irq(gpio_charger->irq, gpio_charger->charger);
-
-	power_supply_unregister(gpio_charger->charger);
+	platform_set_drvdata(pdev, gpio_charger);
 
-	if (gpio_charger->legacy_gpio_requested)
-		gpio_free(gpio_charger->pdata->gpio);
+	ret = devm_device_init_wakeup(dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to init wakeup\n");
 
 	return 0;
 }
@@ -258,8 +388,7 @@ static int gpio_charger_suspend(struct device *dev)
 
 static int gpio_charger_resume(struct device *dev)
 {
-	struct platform_device *pdev = to_platform_device(dev);
-	struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);
+	struct gpio_charger *gpio_charger = dev_get_drvdata(dev);
 
 	if (device_may_wakeup(dev) && gpio_charger->wakeup_enabled)
 		disable_irq_wake(gpio_charger->irq);
@@ -280,7 +409,6 @@ MODULE_DEVICE_TABLE(of, gpio_charger_match);
 
 static struct platform_driver gpio_charger_driver = {
 	.probe = gpio_charger_probe,
-	.remove = gpio_charger_remove,
 	.driver = {
 		.name = "gpio-charger",
 		.pm = &gpio_charger_pm_ops,
@@ -291,6 +419,6 @@ static struct platform_driver gpio_charger_driver = {
 module_platform_driver(gpio_charger_driver);
 
 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
-MODULE_DESCRIPTION("Driver for chargers which report their online status through a GPIO");
+MODULE_DESCRIPTION("Driver for chargers only communicating via GPIO(s)");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:gpio-charger");