2 * LEDs driver for GPIOs
4 * Copyright (C) 2007 8D Technologies inc.
5 * Raphael Assenat <raph@8d.com>
6 * Copyright (C) 2008 Freescale Semiconductor, Inc.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/err.h>
14 #include <linux/gpio.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/kernel.h>
17 #include <linux/leds.h>
18 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <linux/property.h>
22 #include <linux/slab.h>
24 struct gpio_led_data {
25 struct led_classdev cdev;
26 struct gpio_desc *gpiod;
29 gpio_blink_set_t platform_gpio_blink_set;
32 static inline struct gpio_led_data *
33 cdev_to_gpio_led_data(struct led_classdev *led_cdev)
35 return container_of(led_cdev, struct gpio_led_data, cdev);
38 static void gpio_led_set(struct led_classdev *led_cdev,
39 enum led_brightness value)
41 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
49 if (led_dat->blinking) {
50 led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
52 led_dat->blinking = 0;
54 if (led_dat->can_sleep)
55 gpiod_set_value_cansleep(led_dat->gpiod, level);
57 gpiod_set_value(led_dat->gpiod, level);
61 static int gpio_led_set_blocking(struct led_classdev *led_cdev,
62 enum led_brightness value)
64 gpio_led_set(led_cdev, value);
68 static int gpio_blink_set(struct led_classdev *led_cdev,
69 unsigned long *delay_on, unsigned long *delay_off)
71 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
73 led_dat->blinking = 1;
74 return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
78 static int create_gpio_led(const struct gpio_led *template,
79 struct gpio_led_data *led_dat, struct device *parent,
80 struct device_node *np, gpio_blink_set_t blink_set)
84 led_dat->cdev.name = template->name;
85 led_dat->cdev.default_trigger = template->default_trigger;
86 led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
87 if (!led_dat->can_sleep)
88 led_dat->cdev.brightness_set = gpio_led_set;
90 led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
91 led_dat->blinking = 0;
93 led_dat->platform_gpio_blink_set = blink_set;
94 led_dat->cdev.blink_set = gpio_blink_set;
96 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
97 state = gpiod_get_value_cansleep(led_dat->gpiod);
101 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
103 led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
104 if (!template->retain_state_suspended)
105 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
106 if (template->panic_indicator)
107 led_dat->cdev.flags |= LED_PANIC_INDICATOR;
108 if (template->retain_state_shutdown)
109 led_dat->cdev.flags |= LED_RETAIN_AT_SHUTDOWN;
111 ret = gpiod_direction_output(led_dat->gpiod, state);
115 return devm_of_led_classdev_register(parent, np, &led_dat->cdev);
118 struct gpio_leds_priv {
120 struct gpio_led_data leds[];
123 static inline int sizeof_gpio_leds_priv(int num_leds)
125 return sizeof(struct gpio_leds_priv) +
126 (sizeof(struct gpio_led_data) * num_leds);
129 static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
131 struct device *dev = &pdev->dev;
132 struct fwnode_handle *child;
133 struct gpio_leds_priv *priv;
136 count = device_get_child_node_count(dev);
138 return ERR_PTR(-ENODEV);
140 priv = devm_kzalloc(dev, sizeof_gpio_leds_priv(count), GFP_KERNEL);
142 return ERR_PTR(-ENOMEM);
144 device_for_each_child_node(dev, child) {
145 struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
146 struct gpio_led led = {};
147 const char *state = NULL;
148 struct device_node *np = to_of_node(child);
150 ret = fwnode_property_read_string(child, "label", &led.name);
151 if (ret && IS_ENABLED(CONFIG_OF) && np)
154 fwnode_handle_put(child);
155 return ERR_PTR(-EINVAL);
158 led.gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL, child,
161 if (IS_ERR(led.gpiod)) {
162 fwnode_handle_put(child);
163 return ERR_CAST(led.gpiod);
166 fwnode_property_read_string(child, "linux,default-trigger",
167 &led.default_trigger);
169 if (!fwnode_property_read_string(child, "default-state",
171 if (!strcmp(state, "keep"))
172 led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
173 else if (!strcmp(state, "on"))
174 led.default_state = LEDS_GPIO_DEFSTATE_ON;
176 led.default_state = LEDS_GPIO_DEFSTATE_OFF;
179 if (fwnode_property_present(child, "retain-state-suspended"))
180 led.retain_state_suspended = 1;
181 if (fwnode_property_present(child, "retain-state-shutdown"))
182 led.retain_state_shutdown = 1;
183 if (fwnode_property_present(child, "panic-indicator"))
184 led.panic_indicator = 1;
186 ret = create_gpio_led(&led, led_dat, dev, np, NULL);
188 fwnode_handle_put(child);
191 led_dat->cdev.dev->of_node = np;
198 static const struct of_device_id of_gpio_leds_match[] = {
199 { .compatible = "gpio-leds", },
203 MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
205 static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
206 const struct gpio_led *template)
208 struct gpio_desc *gpiod;
209 unsigned long flags = GPIOF_OUT_INIT_LOW;
213 * This means the LED does not come from the device tree
214 * or ACPI, so let's try just getting it by index from the
215 * device, this will hit the board file, if any and get
216 * the GPIO from there.
218 gpiod = devm_gpiod_get_index(dev, NULL, idx, flags);
219 if (!IS_ERR(gpiod)) {
220 gpiod_set_consumer_name(gpiod, template->name);
223 if (PTR_ERR(gpiod) != -ENOENT)
227 * This is the legacy code path for platform code that
228 * still uses GPIO numbers. Ultimately we would like to get
229 * rid of this block completely.
232 /* skip leds that aren't available */
233 if (!gpio_is_valid(template->gpio))
234 return ERR_PTR(-ENOENT);
236 if (template->active_low)
237 flags |= GPIOF_ACTIVE_LOW;
239 ret = devm_gpio_request_one(dev, template->gpio, flags,
244 gpiod = gpio_to_desc(template->gpio);
246 return ERR_PTR(-EINVAL);
251 static int gpio_led_probe(struct platform_device *pdev)
253 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
254 struct gpio_leds_priv *priv;
257 if (pdata && pdata->num_leds) {
258 priv = devm_kzalloc(&pdev->dev,
259 sizeof_gpio_leds_priv(pdata->num_leds),
264 priv->num_leds = pdata->num_leds;
265 for (i = 0; i < priv->num_leds; i++) {
266 const struct gpio_led *template = &pdata->leds[i];
267 struct gpio_led_data *led_dat = &priv->leds[i];
270 led_dat->gpiod = template->gpiod;
273 gpio_led_get_gpiod(&pdev->dev,
275 if (IS_ERR(led_dat->gpiod)) {
276 dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
277 template->gpio, template->name);
281 ret = create_gpio_led(template, led_dat,
283 pdata->gpio_blink_set);
288 priv = gpio_leds_create(pdev);
290 return PTR_ERR(priv);
293 platform_set_drvdata(pdev, priv);
298 static void gpio_led_shutdown(struct platform_device *pdev)
300 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
303 for (i = 0; i < priv->num_leds; i++) {
304 struct gpio_led_data *led = &priv->leds[i];
306 if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
307 gpio_led_set(&led->cdev, LED_OFF);
311 static struct platform_driver gpio_led_driver = {
312 .probe = gpio_led_probe,
313 .shutdown = gpio_led_shutdown,
316 .of_match_table = of_gpio_leds_match,
320 module_platform_driver(gpio_led_driver);
322 MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
323 MODULE_DESCRIPTION("GPIO LED driver");
324 MODULE_LICENSE("GPL");
325 MODULE_ALIAS("platform:leds-gpio");