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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/power/supply/gpio-charger.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | drivers/power/supply/gpio-charger.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/drivers/power/supply/gpio-charger.c b/drivers/power/supply/gpio-charger.c new file mode 100644 index 000000000..68212b397 --- /dev/null +++ b/drivers/power/supply/gpio-charger.c @@ -0,0 +1,400 @@ +// 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 + */ + +#include <linux/device.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/power_supply.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/gpio/consumer.h> + +#include <linux/power/gpio-charger.h> + +struct gpio_mapping { + u32 limit_ua; + u32 gpiodata; +} __packed; + +struct gpio_charger { + 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; + 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) +{ + struct power_supply *charger = devid; + + power_supply_changed(charger); + + return IRQ_HANDLED; +} + +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; + } + 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); + + switch (psp) { + case POWER_SUPPLY_PROP_ONLINE: + val->intval = gpiod_get_value_cansleep(gpio_charger->gpiod); + 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; + } + + return 0; +} + +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); + + 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) +{ + const char *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 irq; +} + +static int init_charge_current_limit(struct device *dev, + struct gpio_charger *gpio_charger) +{ + int i, len; + u32 cur_limit = U32_MAX; + + 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; + + 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; + } + + /* 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) +{ + 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 num_props = 0; + + if (!pdata && !dev->of_node) { + dev_err(dev, "No platform data\n"); + return -ENOENT; + } + + 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_optional(dev, NULL, GPIOD_IN); + if (IS_ERR(gpio_charger->gpiod)) { + /* Just try again if this happens */ + return dev_err_probe(dev, PTR_ERR(gpio_charger->gpiod), + "error getting GPIO descriptor\n"); + } + + if (gpio_charger->gpiod) { + gpio_charger_properties[num_props] = POWER_SUPPLY_PROP_ONLINE; + num_props++; + } + + 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 = 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.of_node = dev->of_node; + psy_cfg.drv_data = gpio_charger; + + 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 = devm_power_supply_register(dev, charger_desc, + &psy_cfg); + if (IS_ERR(gpio_charger->charger)) { + ret = PTR_ERR(gpio_charger->charger); + dev_err(dev, "Failed to register power supply: %d\n", ret); + return ret; + } + + gpio_charger->irq = gpio_charger_get_irq(dev, gpio_charger->charger, + gpio_charger->gpiod); + + charge_status_irq = gpio_charger_get_irq(dev, gpio_charger->charger, + gpio_charger->charge_status); + gpio_charger->charge_status_irq = charge_status_irq; + + platform_set_drvdata(pdev, gpio_charger); + + device_init_wakeup(dev, 1); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int gpio_charger_suspend(struct device *dev) +{ + struct gpio_charger *gpio_charger = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + gpio_charger->wakeup_enabled = + !enable_irq_wake(gpio_charger->irq); + + return 0; +} + +static int gpio_charger_resume(struct device *dev) +{ + struct gpio_charger *gpio_charger = dev_get_drvdata(dev); + + if (device_may_wakeup(dev) && gpio_charger->wakeup_enabled) + disable_irq_wake(gpio_charger->irq); + power_supply_changed(gpio_charger->charger); + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(gpio_charger_pm_ops, + gpio_charger_suspend, gpio_charger_resume); + +static const struct of_device_id gpio_charger_match[] = { + { .compatible = "gpio-charger" }, + { } +}; +MODULE_DEVICE_TABLE(of, gpio_charger_match); + +static struct platform_driver gpio_charger_driver = { + .probe = gpio_charger_probe, + .driver = { + .name = "gpio-charger", + .pm = &gpio_charger_pm_ops, + .of_match_table = gpio_charger_match, + }, +}; + +module_platform_driver(gpio_charger_driver); + +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); +MODULE_DESCRIPTION("Driver for chargers only communicating via GPIO(s)"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:gpio-charger"); |