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/mod_devicetable.h>
15 #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;
52 if (led_dat->can_sleep)
53 gpiod_set_value_cansleep(led_dat->gpiod, level);
55 gpiod_set_value(led_dat->gpiod, level);
59 static int gpio_led_set_blocking(struct led_classdev *led_cdev,
60 enum led_brightness value)
62 gpio_led_set(led_cdev, value);
66 static int gpio_blink_set(struct led_classdev *led_cdev,
67 unsigned long *delay_on, unsigned long *delay_off)
69 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
71 led_dat->blinking = 1;
72 return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
76 static int create_gpio_led(const struct gpio_led *template,
77 struct gpio_led_data *led_dat, struct device *parent,
78 struct fwnode_handle *fwnode, gpio_blink_set_t blink_set)
80 struct led_init_data init_data = {};
81 struct pinctrl *pinctrl;
84 led_dat->cdev.default_trigger = template->default_trigger;
85 led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
86 if (!led_dat->can_sleep)
87 led_dat->cdev.brightness_set = gpio_led_set;
89 led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
90 led_dat->blinking = 0;
92 led_dat->platform_gpio_blink_set = blink_set;
93 led_dat->cdev.blink_set = gpio_blink_set;
95 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
96 state = gpiod_get_value_cansleep(led_dat->gpiod);
100 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
102 led_dat->cdev.brightness = state;
103 led_dat->cdev.max_brightness = 1;
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 if (template->name) {
116 led_dat->cdev.name = template->name;
117 ret = devm_led_classdev_register(parent, &led_dat->cdev);
119 init_data.fwnode = fwnode;
120 ret = devm_led_classdev_register_ext(parent, &led_dat->cdev,
127 pinctrl = devm_pinctrl_get_select_default(led_dat->cdev.dev);
128 ret = PTR_ERR_OR_ZERO(pinctrl);
129 /* pinctrl-%d not present, not an error */
133 dev_warn(led_dat->cdev.dev, "Failed to select %pfw pinctrl: %d\n",
140 struct gpio_leds_priv {
142 struct gpio_led_data leds[] __counted_by(num_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_gpiod_get(dev, child, NULL, GPIOD_ASIS,
171 if (IS_ERR(led.gpiod)) {
172 fwnode_handle_put(child);
173 return ERR_CAST(led.gpiod);
176 led_dat->gpiod = led.gpiod;
178 led.default_state = led_init_default_state_get(child);
180 if (fwnode_property_present(child, "retain-state-suspended"))
181 led.retain_state_suspended = 1;
182 if (fwnode_property_present(child, "retain-state-shutdown"))
183 led.retain_state_shutdown = 1;
184 if (fwnode_property_present(child, "panic-indicator"))
185 led.panic_indicator = 1;
187 ret = create_gpio_led(&led, led_dat, dev, child, NULL);
189 fwnode_handle_put(child);
192 /* Set gpiod label to match the corresponding LED name. */
193 gpiod_set_consumer_name(led_dat->gpiod,
194 led_dat->cdev.dev->kobj.name);
201 static const struct of_device_id of_gpio_leds_match[] = {
202 { .compatible = "gpio-leds", },
206 MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
208 static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
209 const struct gpio_led *template)
211 struct gpio_desc *gpiod;
212 unsigned long flags = GPIOF_OUT_INIT_LOW;
216 * This means the LED does not come from the device tree
217 * or ACPI, so let's try just getting it by index from the
218 * device, this will hit the board file, if any and get
219 * the GPIO from there.
221 gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOD_OUT_LOW);
222 if (!IS_ERR(gpiod)) {
223 gpiod_set_consumer_name(gpiod, template->name);
226 if (PTR_ERR(gpiod) != -ENOENT)
230 * This is the legacy code path for platform code that
231 * still uses GPIO numbers. Ultimately we would like to get
232 * rid of this block completely.
235 /* skip leds that aren't available */
236 if (!gpio_is_valid(template->gpio))
237 return ERR_PTR(-ENOENT);
239 if (template->active_low)
240 flags |= GPIOF_ACTIVE_LOW;
242 ret = devm_gpio_request_one(dev, template->gpio, flags,
247 gpiod = gpio_to_desc(template->gpio);
249 return ERR_PTR(-EINVAL);
254 static int gpio_led_probe(struct platform_device *pdev)
256 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
257 struct gpio_leds_priv *priv;
260 if (pdata && pdata->num_leds) {
261 priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, pdata->num_leds),
266 priv->num_leds = pdata->num_leds;
267 for (i = 0; i < priv->num_leds; i++) {
268 const struct gpio_led *template = &pdata->leds[i];
269 struct gpio_led_data *led_dat = &priv->leds[i];
272 led_dat->gpiod = template->gpiod;
275 gpio_led_get_gpiod(&pdev->dev,
277 if (IS_ERR(led_dat->gpiod)) {
278 dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
279 template->gpio, template->name);
283 ret = create_gpio_led(template, led_dat,
285 pdata->gpio_blink_set);
290 priv = gpio_leds_create(pdev);
292 return PTR_ERR(priv);
295 platform_set_drvdata(pdev, priv);
300 static void gpio_led_shutdown(struct platform_device *pdev)
302 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
305 for (i = 0; i < priv->num_leds; i++) {
306 struct gpio_led_data *led = &priv->leds[i];
308 if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
309 gpio_led_set(&led->cdev, LED_OFF);
313 static struct platform_driver gpio_led_driver = {
314 .probe = gpio_led_probe,
315 .shutdown = gpio_led_shutdown,
318 .of_match_table = of_gpio_leds_match,
322 module_platform_driver(gpio_led_driver);
324 MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
325 MODULE_DESCRIPTION("GPIO LED driver");
326 MODULE_LICENSE("GPL");
327 MODULE_ALIAS("platform:leds-gpio");