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 void gpio_led_set(struct led_classdev *led_cdev,
33 enum led_brightness value)
35 struct gpio_led_data *led_dat =
36 container_of(led_cdev, struct gpio_led_data, cdev);
44 if (led_dat->blinking) {
45 led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
47 led_dat->blinking = 0;
49 if (led_dat->can_sleep)
50 gpiod_set_value_cansleep(led_dat->gpiod, level);
52 gpiod_set_value(led_dat->gpiod, level);
56 static int gpio_led_set_blocking(struct led_classdev *led_cdev,
57 enum led_brightness value)
59 gpio_led_set(led_cdev, value);
63 static int gpio_blink_set(struct led_classdev *led_cdev,
64 unsigned long *delay_on, unsigned long *delay_off)
66 struct gpio_led_data *led_dat =
67 container_of(led_cdev, struct gpio_led_data, cdev);
69 led_dat->blinking = 1;
70 return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
74 static int create_gpio_led(const struct gpio_led *template,
75 struct gpio_led_data *led_dat, struct device *parent,
76 gpio_blink_set_t blink_set)
80 led_dat->gpiod = template->gpiod;
81 if (!led_dat->gpiod) {
83 * This is the legacy code path for platform code that
84 * still uses GPIO numbers. Ultimately we would like to get
85 * rid of this block completely.
87 unsigned long flags = GPIOF_OUT_INIT_LOW;
89 /* skip leds that aren't available */
90 if (!gpio_is_valid(template->gpio)) {
91 dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n",
92 template->gpio, template->name);
96 if (template->active_low)
97 flags |= GPIOF_ACTIVE_LOW;
99 ret = devm_gpio_request_one(parent, template->gpio, flags,
104 led_dat->gpiod = gpio_to_desc(template->gpio);
109 led_dat->cdev.name = template->name;
110 led_dat->cdev.default_trigger = template->default_trigger;
111 led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
112 if (!led_dat->can_sleep)
113 led_dat->cdev.brightness_set = gpio_led_set;
115 led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
116 led_dat->blinking = 0;
118 led_dat->platform_gpio_blink_set = blink_set;
119 led_dat->cdev.blink_set = gpio_blink_set;
121 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP)
122 state = !!gpiod_get_value_cansleep(led_dat->gpiod);
124 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
125 led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
126 if (!template->retain_state_suspended)
127 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
128 if (template->panic_indicator)
129 led_dat->cdev.flags |= LED_PANIC_INDICATOR;
131 ret = gpiod_direction_output(led_dat->gpiod, state);
135 return led_classdev_register(parent, &led_dat->cdev);
138 struct gpio_leds_priv {
140 struct gpio_led_data leds[];
143 static inline int sizeof_gpio_leds_priv(int num_leds)
145 return sizeof(struct gpio_leds_priv) +
146 (sizeof(struct gpio_led_data) * num_leds);
149 static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
151 struct device *dev = &pdev->dev;
152 struct fwnode_handle *child;
153 struct gpio_leds_priv *priv;
155 struct device_node *np;
157 count = device_get_child_node_count(dev);
159 return ERR_PTR(-ENODEV);
161 priv = devm_kzalloc(dev, sizeof_gpio_leds_priv(count), GFP_KERNEL);
163 return ERR_PTR(-ENOMEM);
165 device_for_each_child_node(dev, child) {
166 struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
167 struct gpio_led led = {};
168 const char *state = NULL;
170 led.gpiod = devm_get_gpiod_from_child(dev, NULL, child);
171 if (IS_ERR(led.gpiod)) {
172 fwnode_handle_put(child);
173 ret = PTR_ERR(led.gpiod);
177 np = to_of_node(child);
179 if (fwnode_property_present(child, "label")) {
180 fwnode_property_read_string(child, "label", &led.name);
182 if (IS_ENABLED(CONFIG_OF) && !led.name && np)
189 fwnode_property_read_string(child, "linux,default-trigger",
190 &led.default_trigger);
192 if (!fwnode_property_read_string(child, "default-state",
194 if (!strcmp(state, "keep"))
195 led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
196 else if (!strcmp(state, "on"))
197 led.default_state = LEDS_GPIO_DEFSTATE_ON;
199 led.default_state = LEDS_GPIO_DEFSTATE_OFF;
202 if (fwnode_property_present(child, "retain-state-suspended"))
203 led.retain_state_suspended = 1;
204 if (fwnode_property_present(child, "panic-indicator"))
205 led.panic_indicator = 1;
207 ret = create_gpio_led(&led, led_dat, dev, NULL);
209 fwnode_handle_put(child);
212 led_dat->cdev.dev->of_node = np;
219 for (count = priv->num_leds - 1; count >= 0; count--)
220 led_classdev_unregister(&priv->leds[count].cdev);
224 static const struct of_device_id of_gpio_leds_match[] = {
225 { .compatible = "gpio-leds", },
229 MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
231 static int gpio_led_probe(struct platform_device *pdev)
233 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
234 struct gpio_leds_priv *priv;
237 if (pdata && pdata->num_leds) {
238 priv = devm_kzalloc(&pdev->dev,
239 sizeof_gpio_leds_priv(pdata->num_leds),
244 priv->num_leds = pdata->num_leds;
245 for (i = 0; i < priv->num_leds; i++) {
246 ret = create_gpio_led(&pdata->leds[i],
248 &pdev->dev, pdata->gpio_blink_set);
250 /* On failure: unwind the led creations */
251 for (i = i - 1; i >= 0; i--)
252 led_classdev_unregister(
253 &priv->leds[i].cdev);
258 priv = gpio_leds_create(pdev);
260 return PTR_ERR(priv);
263 platform_set_drvdata(pdev, priv);
268 static int gpio_led_remove(struct platform_device *pdev)
270 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
273 for (i = 0; i < priv->num_leds; i++)
274 led_classdev_unregister(&priv->leds[i].cdev);
279 static void gpio_led_shutdown(struct platform_device *pdev)
281 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
284 for (i = 0; i < priv->num_leds; i++) {
285 struct gpio_led_data *led = &priv->leds[i];
287 gpio_led_set(&led->cdev, LED_OFF);
291 static struct platform_driver gpio_led_driver = {
292 .probe = gpio_led_probe,
293 .remove = gpio_led_remove,
294 .shutdown = gpio_led_shutdown,
297 .of_match_table = of_gpio_leds_match,
301 module_platform_driver(gpio_led_driver);
303 MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
304 MODULE_DESCRIPTION("GPIO LED driver");
305 MODULE_LICENSE("GPL");
306 MODULE_ALIAS("platform:leds-gpio");