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/pinctrl/consumer.h>
17 #include <linux/platform_device.h>
18 #include <linux/property.h>
19 #include <linux/slab.h>
22 struct gpio_led_data {
23 struct led_classdev cdev;
24 struct gpio_desc *gpiod;
27 gpio_blink_set_t platform_gpio_blink_set;
30 static inline struct gpio_led_data *
31 cdev_to_gpio_led_data(struct led_classdev *led_cdev)
33 return container_of(led_cdev, struct gpio_led_data, cdev);
36 static void gpio_led_set(struct led_classdev *led_cdev,
37 enum led_brightness value)
39 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
47 if (led_dat->blinking) {
48 led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
50 led_dat->blinking = 0;
51 } else if (led_dat->cdev.flags & SET_GPIO_INPUT) {
52 gpiod_direction_input(led_dat->gpiod);
53 led_dat->cdev.flags &= ~SET_GPIO_INPUT;
54 } else if (led_dat->cdev.flags & SET_GPIO_OUTPUT) {
55 gpiod_direction_output(led_dat->gpiod, level);
56 led_dat->cdev.flags &= ~SET_GPIO_OUTPUT;
58 if (led_dat->can_sleep ||
59 (led_dat->cdev.flags & (SET_GPIO_INPUT | SET_GPIO_OUTPUT) ))
60 gpiod_set_value_cansleep(led_dat->gpiod, level);
62 gpiod_set_value(led_dat->gpiod, level);
66 static int gpio_led_set_blocking(struct led_classdev *led_cdev,
67 enum led_brightness value)
69 gpio_led_set(led_cdev, value);
73 static enum led_brightness gpio_led_get(struct led_classdev *led_cdev)
75 struct gpio_led_data *led_dat =
76 container_of(led_cdev, struct gpio_led_data, cdev);
77 return gpiod_get_value_cansleep(led_dat->gpiod) ? LED_FULL : LED_OFF;
80 static int gpio_blink_set(struct led_classdev *led_cdev,
81 unsigned long *delay_on, unsigned long *delay_off)
83 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
85 led_dat->blinking = 1;
86 return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
90 static int create_gpio_led(const struct gpio_led *template,
91 struct gpio_led_data *led_dat, struct device *parent,
92 struct fwnode_handle *fwnode, gpio_blink_set_t blink_set)
94 struct led_init_data init_data = {};
95 struct pinctrl *pinctrl;
98 led_dat->cdev.default_trigger = template->default_trigger;
99 led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
100 if (!led_dat->can_sleep)
101 led_dat->cdev.brightness_set = gpio_led_set;
103 led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
104 led_dat->blinking = 0;
106 led_dat->platform_gpio_blink_set = blink_set;
107 led_dat->cdev.blink_set = gpio_blink_set;
109 led_dat->cdev.brightness_get = gpio_led_get;
110 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
111 state = gpiod_get_value_cansleep(led_dat->gpiod);
115 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
117 led_dat->cdev.brightness = state;
118 led_dat->cdev.max_brightness = 1;
119 if (!template->retain_state_suspended)
120 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
121 if (template->panic_indicator)
122 led_dat->cdev.flags |= LED_PANIC_INDICATOR;
123 if (template->retain_state_shutdown)
124 led_dat->cdev.flags |= LED_RETAIN_AT_SHUTDOWN;
126 ret = gpiod_direction_output(led_dat->gpiod, state);
130 if (template->name) {
131 led_dat->cdev.name = template->name;
132 ret = devm_led_classdev_register(parent, &led_dat->cdev);
134 init_data.fwnode = fwnode;
135 ret = devm_led_classdev_register_ext(parent, &led_dat->cdev,
142 pinctrl = devm_pinctrl_get_select_default(led_dat->cdev.dev);
143 if (IS_ERR(pinctrl)) {
144 ret = PTR_ERR(pinctrl);
145 if (ret != -ENODEV) {
146 dev_warn(led_dat->cdev.dev,
147 "Failed to select %pOF pinctrl: %d\n",
148 to_of_node(fwnode), ret);
150 /* pinctrl-%d not present, not an error */
158 struct gpio_leds_priv {
160 struct gpio_led_data leds[];
163 static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
165 struct device *dev = &pdev->dev;
166 struct fwnode_handle *child;
167 struct gpio_leds_priv *priv;
170 count = device_get_child_node_count(dev);
172 return ERR_PTR(-ENODEV);
174 priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
176 return ERR_PTR(-ENOMEM);
178 device_for_each_child_node(dev, child) {
179 struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
180 struct gpio_led led = {};
183 * Acquire gpiod from DT with uninitialized label, which
184 * will be updated after LED class device is registered,
185 * Only then the final LED name is known.
187 led.gpiod = devm_fwnode_gpiod_get(dev, child, NULL, GPIOD_ASIS,
189 if (IS_ERR(led.gpiod)) {
190 fwnode_handle_put(child);
191 return ERR_CAST(led.gpiod);
194 led_dat->gpiod = led.gpiod;
196 led.default_state = led_init_default_state_get(child);
198 if (fwnode_property_present(child, "retain-state-suspended"))
199 led.retain_state_suspended = 1;
200 if (fwnode_property_present(child, "retain-state-shutdown"))
201 led.retain_state_shutdown = 1;
202 if (fwnode_property_present(child, "panic-indicator"))
203 led.panic_indicator = 1;
205 ret = create_gpio_led(&led, led_dat, dev, child, NULL);
207 fwnode_handle_put(child);
210 /* Set gpiod label to match the corresponding LED name. */
211 gpiod_set_consumer_name(led_dat->gpiod,
212 led_dat->cdev.dev->kobj.name);
219 static const struct of_device_id of_gpio_leds_match[] = {
220 { .compatible = "gpio-leds", },
224 MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
226 static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
227 const struct gpio_led *template)
229 struct gpio_desc *gpiod;
230 unsigned long flags = GPIOF_OUT_INIT_LOW;
234 * This means the LED does not come from the device tree
235 * or ACPI, so let's try just getting it by index from the
236 * device, this will hit the board file, if any and get
237 * the GPIO from there.
239 gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOD_OUT_LOW);
240 if (!IS_ERR(gpiod)) {
241 gpiod_set_consumer_name(gpiod, template->name);
244 if (PTR_ERR(gpiod) != -ENOENT)
248 * This is the legacy code path for platform code that
249 * still uses GPIO numbers. Ultimately we would like to get
250 * rid of this block completely.
253 /* skip leds that aren't available */
254 if (!gpio_is_valid(template->gpio))
255 return ERR_PTR(-ENOENT);
257 if (template->active_low)
258 flags |= GPIOF_ACTIVE_LOW;
260 ret = devm_gpio_request_one(dev, template->gpio, flags,
265 gpiod = gpio_to_desc(template->gpio);
267 return ERR_PTR(-EINVAL);
272 static int gpio_led_probe(struct platform_device *pdev)
274 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
275 struct gpio_leds_priv *priv;
278 if (pdata && pdata->num_leds) {
279 priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, pdata->num_leds),
284 priv->num_leds = pdata->num_leds;
285 for (i = 0; i < priv->num_leds; i++) {
286 const struct gpio_led *template = &pdata->leds[i];
287 struct gpio_led_data *led_dat = &priv->leds[i];
290 led_dat->gpiod = template->gpiod;
293 gpio_led_get_gpiod(&pdev->dev,
295 if (IS_ERR(led_dat->gpiod)) {
296 dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
297 template->gpio, template->name);
301 ret = create_gpio_led(template, led_dat,
303 pdata->gpio_blink_set);
308 priv = gpio_leds_create(pdev);
310 return PTR_ERR(priv);
313 platform_set_drvdata(pdev, priv);
318 static void gpio_led_shutdown(struct platform_device *pdev)
320 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
323 for (i = 0; i < priv->num_leds; i++) {
324 struct gpio_led_data *led = &priv->leds[i];
326 if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
327 gpio_led_set(&led->cdev, LED_OFF);
331 static struct platform_driver gpio_led_driver = {
332 .probe = gpio_led_probe,
333 .shutdown = gpio_led_shutdown,
336 .of_match_table = of_gpio_leds_match,
340 module_platform_driver(gpio_led_driver);
342 MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
343 MODULE_DESCRIPTION("GPIO LED driver");
344 MODULE_LICENSE("GPL");
345 MODULE_ALIAS("platform:leds-gpio");