| /* |
| * LEDs driver for GPIOs |
| * |
| * Copyright (C) 2007 8D Technologies inc. |
| * Raphael Assenat <raph@8d.com> |
| * Copyright (C) 2008 Freescale Semiconductor, Inc. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| */ |
| #include <linux/err.h> |
| #include <linux/gpio.h> |
| #include <linux/gpio/consumer.h> |
| #include <linux/kernel.h> |
| #include <linux/leds.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/property.h> |
| #include <linux/slab.h> |
| |
| struct gpio_led_data { |
| struct led_classdev cdev; |
| struct gpio_desc *gpiod; |
| u8 can_sleep; |
| u8 blinking; |
| int (*platform_gpio_blink_set)(struct gpio_desc *desc, int state, |
| unsigned long *delay_on, unsigned long *delay_off); |
| }; |
| |
| static void gpio_led_set(struct led_classdev *led_cdev, |
| enum led_brightness value) |
| { |
| struct gpio_led_data *led_dat = |
| container_of(led_cdev, struct gpio_led_data, cdev); |
| int level; |
| |
| if (value == LED_OFF) |
| level = 0; |
| else |
| level = 1; |
| |
| if (led_dat->blinking) { |
| led_dat->platform_gpio_blink_set(led_dat->gpiod, level, |
| NULL, NULL); |
| led_dat->blinking = 0; |
| } else { |
| if (led_dat->can_sleep) |
| gpiod_set_value_cansleep(led_dat->gpiod, level); |
| else |
| gpiod_set_value(led_dat->gpiod, level); |
| } |
| } |
| |
| static int gpio_led_set_blocking(struct led_classdev *led_cdev, |
| enum led_brightness value) |
| { |
| gpio_led_set(led_cdev, value); |
| return 0; |
| } |
| |
| static int gpio_blink_set(struct led_classdev *led_cdev, |
| unsigned long *delay_on, unsigned long *delay_off) |
| { |
| struct gpio_led_data *led_dat = |
| container_of(led_cdev, struct gpio_led_data, cdev); |
| |
| led_dat->blinking = 1; |
| return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK, |
| delay_on, delay_off); |
| } |
| |
| static int create_gpio_led(const struct gpio_led *template, |
| struct gpio_led_data *led_dat, struct device *parent, |
| int (*blink_set)(struct gpio_desc *, int, unsigned long *, |
| unsigned long *)) |
| { |
| int ret, state; |
| |
| led_dat->gpiod = template->gpiod; |
| if (!led_dat->gpiod) { |
| /* |
| * This is the legacy code path for platform code that |
| * still uses GPIO numbers. Ultimately we would like to get |
| * rid of this block completely. |
| */ |
| unsigned long flags = 0; |
| |
| /* skip leds that aren't available */ |
| if (!gpio_is_valid(template->gpio)) { |
| dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n", |
| template->gpio, template->name); |
| return 0; |
| } |
| |
| if (template->active_low) |
| flags |= GPIOF_ACTIVE_LOW; |
| |
| ret = devm_gpio_request_one(parent, template->gpio, flags, |
| template->name); |
| if (ret < 0) |
| return ret; |
| |
| led_dat->gpiod = gpio_to_desc(template->gpio); |
| if (!led_dat->gpiod) |
| return -EINVAL; |
| } |
| |
| led_dat->cdev.name = template->name; |
| led_dat->cdev.default_trigger = template->default_trigger; |
| led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod); |
| if (!led_dat->can_sleep) |
| led_dat->cdev.brightness_set = gpio_led_set; |
| else |
| led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking; |
| led_dat->blinking = 0; |
| if (blink_set) { |
| led_dat->platform_gpio_blink_set = blink_set; |
| led_dat->cdev.blink_set = gpio_blink_set; |
| } |
| if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) |
| state = !!gpiod_get_value_cansleep(led_dat->gpiod); |
| else |
| state = (template->default_state == LEDS_GPIO_DEFSTATE_ON); |
| led_dat->cdev.brightness = state ? LED_FULL : LED_OFF; |
| if (!template->retain_state_suspended) |
| led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME; |
| |
| ret = gpiod_direction_output(led_dat->gpiod, state); |
| if (ret < 0) |
| return ret; |
| |
| return led_classdev_register(parent, &led_dat->cdev); |
| } |
| |
| struct gpio_leds_priv { |
| int num_leds; |
| struct gpio_led_data leds[]; |
| }; |
| |
| static inline int sizeof_gpio_leds_priv(int num_leds) |
| { |
| return sizeof(struct gpio_leds_priv) + |
| (sizeof(struct gpio_led_data) * num_leds); |
| } |
| |
| static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct fwnode_handle *child; |
| struct gpio_leds_priv *priv; |
| int count, ret; |
| struct device_node *np; |
| |
| count = device_get_child_node_count(dev); |
| if (!count) |
| return ERR_PTR(-ENODEV); |
| |
| priv = devm_kzalloc(dev, sizeof_gpio_leds_priv(count), GFP_KERNEL); |
| if (!priv) |
| return ERR_PTR(-ENOMEM); |
| |
| device_for_each_child_node(dev, child) { |
| struct gpio_led led = {}; |
| const char *state = NULL; |
| |
| led.gpiod = devm_get_gpiod_from_child(dev, NULL, child); |
| if (IS_ERR(led.gpiod)) { |
| fwnode_handle_put(child); |
| ret = PTR_ERR(led.gpiod); |
| goto err; |
| } |
| |
| np = to_of_node(child); |
| |
| if (fwnode_property_present(child, "label")) { |
| fwnode_property_read_string(child, "label", &led.name); |
| } else { |
| if (IS_ENABLED(CONFIG_OF) && !led.name && np) |
| led.name = np->name; |
| if (!led.name) { |
| ret = -EINVAL; |
| goto err; |
| } |
| } |
| fwnode_property_read_string(child, "linux,default-trigger", |
| &led.default_trigger); |
| |
| if (!fwnode_property_read_string(child, "default-state", |
| &state)) { |
| if (!strcmp(state, "keep")) |
| led.default_state = LEDS_GPIO_DEFSTATE_KEEP; |
| else if (!strcmp(state, "on")) |
| led.default_state = LEDS_GPIO_DEFSTATE_ON; |
| else |
| led.default_state = LEDS_GPIO_DEFSTATE_OFF; |
| } |
| |
| if (fwnode_property_present(child, "retain-state-suspended")) |
| led.retain_state_suspended = 1; |
| |
| ret = create_gpio_led(&led, &priv->leds[priv->num_leds], |
| dev, NULL); |
| if (ret < 0) { |
| fwnode_handle_put(child); |
| goto err; |
| } |
| priv->num_leds++; |
| } |
| |
| return priv; |
| |
| err: |
| for (count = priv->num_leds - 1; count >= 0; count--) |
| led_classdev_unregister(&priv->leds[count].cdev); |
| return ERR_PTR(ret); |
| } |
| |
| static const struct of_device_id of_gpio_leds_match[] = { |
| { .compatible = "gpio-leds", }, |
| {}, |
| }; |
| |
| MODULE_DEVICE_TABLE(of, of_gpio_leds_match); |
| |
| static int gpio_led_probe(struct platform_device *pdev) |
| { |
| struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev); |
| struct gpio_leds_priv *priv; |
| int i, ret = 0; |
| |
| if (pdata && pdata->num_leds) { |
| priv = devm_kzalloc(&pdev->dev, |
| sizeof_gpio_leds_priv(pdata->num_leds), |
| GFP_KERNEL); |
| if (!priv) |
| return -ENOMEM; |
| |
| priv->num_leds = pdata->num_leds; |
| for (i = 0; i < priv->num_leds; i++) { |
| ret = create_gpio_led(&pdata->leds[i], |
| &priv->leds[i], |
| &pdev->dev, pdata->gpio_blink_set); |
| if (ret < 0) { |
| /* On failure: unwind the led creations */ |
| for (i = i - 1; i >= 0; i--) |
| led_classdev_unregister( |
| &priv->leds[i].cdev); |
| return ret; |
| } |
| } |
| } else { |
| priv = gpio_leds_create(pdev); |
| if (IS_ERR(priv)) |
| return PTR_ERR(priv); |
| } |
| |
| platform_set_drvdata(pdev, priv); |
| |
| return 0; |
| } |
| |
| static int gpio_led_remove(struct platform_device *pdev) |
| { |
| struct gpio_leds_priv *priv = platform_get_drvdata(pdev); |
| int i; |
| |
| for (i = 0; i < priv->num_leds; i++) |
| led_classdev_unregister(&priv->leds[i].cdev); |
| |
| return 0; |
| } |
| |
| static void gpio_led_shutdown(struct platform_device *pdev) |
| { |
| struct gpio_leds_priv *priv = platform_get_drvdata(pdev); |
| int i; |
| |
| for (i = 0; i < priv->num_leds; i++) { |
| struct gpio_led_data *led = &priv->leds[i]; |
| |
| gpio_led_set(&led->cdev, LED_OFF); |
| } |
| } |
| |
| static struct platform_driver gpio_led_driver = { |
| .probe = gpio_led_probe, |
| .remove = gpio_led_remove, |
| .shutdown = gpio_led_shutdown, |
| .driver = { |
| .name = "leds-gpio", |
| .of_match_table = of_gpio_leds_match, |
| }, |
| }; |
| |
| module_platform_driver(gpio_led_driver); |
| |
| MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>"); |
| MODULE_DESCRIPTION("GPIO LED driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:leds-gpio"); |