/* * LEDs driver for GPIOs * * Copyright (C) 2007 8D Technologies inc. * Raphael Assenat * 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 #include #include #include #include #include #include #include #include #include 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 , Trent Piepho "); MODULE_DESCRIPTION("GPIO LED driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:leds-gpio");