1 // SPDX-License-Identifier: GPL-2.0-only
3 * LEDs driver for GPIOs
5 * Copyright (C) 2007 8D Technologies inc.
6 * Raphael Assenat <raph@8d.com>
7 * Copyright (C) 2008 Freescale Semiconductor, Inc.
10 #include <linux/gpio.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/kernel.h>
13 #include <linux/leds.h>
14 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/property.h>
18 #include <linux/slab.h>
21 struct gpio_led_data {
22 struct led_classdev cdev;
23 struct gpio_desc *gpiod;
26 gpio_blink_set_t platform_gpio_blink_set;
29 static inline struct gpio_led_data *
30 cdev_to_gpio_led_data(struct led_classdev *led_cdev)
32 return container_of(led_cdev, struct gpio_led_data, cdev);
35 static void gpio_led_set(struct led_classdev *led_cdev,
36 enum led_brightness value)
38 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
46 if (led_dat->blinking) {
47 led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
49 led_dat->blinking = 0;
50 } else if (led_dat->cdev.flags & SET_GPIO_INPUT) {
51 gpiod_direction_input(led_dat->gpiod);
52 led_dat->cdev.flags &= ~SET_GPIO_INPUT;
53 } else if (led_dat->cdev.flags & SET_GPIO_OUTPUT) {
54 gpiod_direction_output(led_dat->gpiod, level);
55 led_dat->cdev.flags &= ~SET_GPIO_OUTPUT;
57 if (led_dat->can_sleep ||
58 (led_dat->cdev.flags & (SET_GPIO_INPUT | SET_GPIO_OUTPUT) ))
59 gpiod_set_value_cansleep(led_dat->gpiod, level);
61 gpiod_set_value(led_dat->gpiod, level);
65 static int gpio_led_set_blocking(struct led_classdev *led_cdev,
66 enum led_brightness value)
68 gpio_led_set(led_cdev, value);
72 static enum led_brightness gpio_led_get(struct led_classdev *led_cdev)
74 struct gpio_led_data *led_dat =
75 container_of(led_cdev, struct gpio_led_data, cdev);
76 return gpiod_get_value_cansleep(led_dat->gpiod) ? LED_FULL : LED_OFF;
79 static int gpio_blink_set(struct led_classdev *led_cdev,
80 unsigned long *delay_on, unsigned long *delay_off)
82 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
84 led_dat->blinking = 1;
85 return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
89 static int create_gpio_led(const struct gpio_led *template,
90 struct gpio_led_data *led_dat, struct device *parent,
91 struct fwnode_handle *fwnode, gpio_blink_set_t blink_set)
93 struct led_init_data init_data = {};
96 led_dat->cdev.default_trigger = template->default_trigger;
97 led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
98 if (!led_dat->can_sleep)
99 led_dat->cdev.brightness_set = gpio_led_set;
101 led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
102 led_dat->blinking = 0;
104 led_dat->platform_gpio_blink_set = blink_set;
105 led_dat->cdev.blink_set = gpio_blink_set;
107 led_dat->cdev.brightness_get = gpio_led_get;
108 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
109 state = gpiod_get_value_cansleep(led_dat->gpiod);
113 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
115 led_dat->cdev.brightness = state;
116 led_dat->cdev.max_brightness = 1;
117 if (!template->retain_state_suspended)
118 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
119 if (template->panic_indicator)
120 led_dat->cdev.flags |= LED_PANIC_INDICATOR;
121 if (template->retain_state_shutdown)
122 led_dat->cdev.flags |= LED_RETAIN_AT_SHUTDOWN;
124 ret = gpiod_direction_output(led_dat->gpiod, state);
128 if (template->name) {
129 led_dat->cdev.name = template->name;
130 ret = devm_led_classdev_register(parent, &led_dat->cdev);
132 init_data.fwnode = fwnode;
133 ret = devm_led_classdev_register_ext(parent, &led_dat->cdev,
140 struct gpio_leds_priv {
142 struct gpio_led_data leds[];
145 static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
147 struct device *dev = &pdev->dev;
148 struct fwnode_handle *child;
149 struct gpio_leds_priv *priv;
152 count = device_get_child_node_count(dev);
154 return ERR_PTR(-ENODEV);
156 priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
158 return ERR_PTR(-ENOMEM);
160 device_for_each_child_node(dev, child) {
161 struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
162 struct gpio_led led = {};
165 * Acquire gpiod from DT with uninitialized label, which
166 * will be updated after LED class device is registered,
167 * Only then the final LED name is known.
169 led.gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL, child,
172 if (IS_ERR(led.gpiod)) {
173 fwnode_handle_put(child);
174 return ERR_CAST(led.gpiod);
177 led_dat->gpiod = led.gpiod;
179 led.default_state = led_init_default_state_get(child);
181 if (fwnode_property_present(child, "retain-state-suspended"))
182 led.retain_state_suspended = 1;
183 if (fwnode_property_present(child, "retain-state-shutdown"))
184 led.retain_state_shutdown = 1;
185 if (fwnode_property_present(child, "panic-indicator"))
186 led.panic_indicator = 1;
188 ret = create_gpio_led(&led, led_dat, dev, child, NULL);
190 fwnode_handle_put(child);
193 /* Set gpiod label to match the corresponding LED name. */
194 gpiod_set_consumer_name(led_dat->gpiod,
195 led_dat->cdev.dev->kobj.name);
202 static const struct of_device_id of_gpio_leds_match[] = {
203 { .compatible = "gpio-leds", },
207 MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
209 static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
210 const struct gpio_led *template)
212 struct gpio_desc *gpiod;
213 unsigned long flags = GPIOF_OUT_INIT_LOW;
217 * This means the LED does not come from the device tree
218 * or ACPI, so let's try just getting it by index from the
219 * device, this will hit the board file, if any and get
220 * the GPIO from there.
222 gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOD_OUT_LOW);
223 if (!IS_ERR(gpiod)) {
224 gpiod_set_consumer_name(gpiod, template->name);
227 if (PTR_ERR(gpiod) != -ENOENT)
231 * This is the legacy code path for platform code that
232 * still uses GPIO numbers. Ultimately we would like to get
233 * rid of this block completely.
236 /* skip leds that aren't available */
237 if (!gpio_is_valid(template->gpio))
238 return ERR_PTR(-ENOENT);
240 if (template->active_low)
241 flags |= GPIOF_ACTIVE_LOW;
243 ret = devm_gpio_request_one(dev, template->gpio, flags,
248 gpiod = gpio_to_desc(template->gpio);
250 return ERR_PTR(-EINVAL);
255 static int gpio_led_probe(struct platform_device *pdev)
257 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
258 struct gpio_leds_priv *priv;
261 if (pdata && pdata->num_leds) {
262 priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, pdata->num_leds),
267 priv->num_leds = pdata->num_leds;
268 for (i = 0; i < priv->num_leds; i++) {
269 const struct gpio_led *template = &pdata->leds[i];
270 struct gpio_led_data *led_dat = &priv->leds[i];
273 led_dat->gpiod = template->gpiod;
276 gpio_led_get_gpiod(&pdev->dev,
278 if (IS_ERR(led_dat->gpiod)) {
279 dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
280 template->gpio, template->name);
284 ret = create_gpio_led(template, led_dat,
286 pdata->gpio_blink_set);
291 priv = gpio_leds_create(pdev);
293 return PTR_ERR(priv);
296 platform_set_drvdata(pdev, priv);
301 static void gpio_led_shutdown(struct platform_device *pdev)
303 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
306 for (i = 0; i < priv->num_leds; i++) {
307 struct gpio_led_data *led = &priv->leds[i];
309 if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
310 gpio_led_set(&led->cdev, LED_OFF);
314 static struct platform_driver gpio_led_driver = {
315 .probe = gpio_led_probe,
316 .shutdown = gpio_led_shutdown,
319 .of_match_table = of_gpio_leds_match,
323 module_platform_driver(gpio_led_driver);
325 MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
326 MODULE_DESCRIPTION("GPIO LED driver");
327 MODULE_LICENSE("GPL");
328 MODULE_ALIAS("platform:leds-gpio");