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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * LEDs driver for GPIOs
  4 *
  5 * Copyright (C) 2007 8D Technologies inc.
  6 * Raphael Assenat <raph@8d.com>
  7 * Copyright (C) 2008 Freescale Semiconductor, Inc.
  8 */
  9#include <linux/err.h>
 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>
 15#include <linux/of.h>
 16#include <linux/platform_device.h>
 17#include <linux/property.h>
 18#include <linux/slab.h>
 19#include "leds.h"
 20
 21struct gpio_led_data {
 22	struct led_classdev cdev;
 23	struct gpio_desc *gpiod;
 24	u8 can_sleep;
 25	u8 blinking;
 26	gpio_blink_set_t platform_gpio_blink_set;
 27};
 28
 29static inline struct gpio_led_data *
 30			cdev_to_gpio_led_data(struct led_classdev *led_cdev)
 31{
 32	return container_of(led_cdev, struct gpio_led_data, cdev);
 33}
 34
 35static void gpio_led_set(struct led_classdev *led_cdev,
 36	enum led_brightness value)
 37{
 38	struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
 39	int level;
 40
 41	if (value == LED_OFF)
 42		level = 0;
 43	else
 44		level = 1;
 45
 46	if (led_dat->blinking) {
 47		led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
 48						 NULL, NULL);
 49		led_dat->blinking = 0;
 50	} else {
 51		if (led_dat->can_sleep)
 52			gpiod_set_value_cansleep(led_dat->gpiod, level);
 53		else
 54			gpiod_set_value(led_dat->gpiod, level);
 55	}
 56}
 57
 58static int gpio_led_set_blocking(struct led_classdev *led_cdev,
 59	enum led_brightness value)
 60{
 61	gpio_led_set(led_cdev, value);
 62	return 0;
 63}
 64
 65static int gpio_blink_set(struct led_classdev *led_cdev,
 66	unsigned long *delay_on, unsigned long *delay_off)
 67{
 68	struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
 69
 70	led_dat->blinking = 1;
 71	return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
 72						delay_on, delay_off);
 73}
 74
 75static int create_gpio_led(const struct gpio_led *template,
 76	struct gpio_led_data *led_dat, struct device *parent,
 77	struct fwnode_handle *fwnode, gpio_blink_set_t blink_set)
 78{
 79	struct led_init_data init_data = {};
 80	int ret, state;
 81
 82	led_dat->cdev.default_trigger = template->default_trigger;
 83	led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
 84	if (!led_dat->can_sleep)
 85		led_dat->cdev.brightness_set = gpio_led_set;
 86	else
 87		led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
 88	led_dat->blinking = 0;
 89	if (blink_set) {
 90		led_dat->platform_gpio_blink_set = blink_set;
 91		led_dat->cdev.blink_set = gpio_blink_set;
 92	}
 93	if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
 94		state = gpiod_get_value_cansleep(led_dat->gpiod);
 95		if (state < 0)
 96			return state;
 97	} else {
 98		state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
 99	}
100	led_dat->cdev.brightness = state;
101	led_dat->cdev.max_brightness = 1;
102	if (!template->retain_state_suspended)
103		led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
104	if (template->panic_indicator)
105		led_dat->cdev.flags |= LED_PANIC_INDICATOR;
106	if (template->retain_state_shutdown)
107		led_dat->cdev.flags |= LED_RETAIN_AT_SHUTDOWN;
108
109	ret = gpiod_direction_output(led_dat->gpiod, state);
110	if (ret < 0)
111		return ret;
112
113	if (template->name) {
114		led_dat->cdev.name = template->name;
115		ret = devm_led_classdev_register(parent, &led_dat->cdev);
116	} else {
117		init_data.fwnode = fwnode;
118		ret = devm_led_classdev_register_ext(parent, &led_dat->cdev,
119						     &init_data);
120	}
121
122	return ret;
123}
124
125struct gpio_leds_priv {
126	int num_leds;
127	struct gpio_led_data leds[];
128};
129
130static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
131{
132	struct device *dev = &pdev->dev;
133	struct fwnode_handle *child;
134	struct gpio_leds_priv *priv;
135	int count, ret;
136
137	count = device_get_child_node_count(dev);
138	if (!count)
139		return ERR_PTR(-ENODEV);
140
141	priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
142	if (!priv)
143		return ERR_PTR(-ENOMEM);
144
145	device_for_each_child_node(dev, child) {
146		struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
147		struct gpio_led led = {};
 
148
149		/*
150		 * Acquire gpiod from DT with uninitialized label, which
151		 * will be updated after LED class device is registered,
152		 * Only then the final LED name is known.
153		 */
154		led.gpiod = devm_fwnode_gpiod_get(dev, child, NULL, GPIOD_ASIS,
155						  NULL);
 
156		if (IS_ERR(led.gpiod)) {
157			fwnode_handle_put(child);
158			return ERR_CAST(led.gpiod);
159		}
160
161		led_dat->gpiod = led.gpiod;
162
163		led.default_state = led_init_default_state_get(child);
 
 
 
 
 
 
 
 
164
165		if (fwnode_property_present(child, "retain-state-suspended"))
166			led.retain_state_suspended = 1;
167		if (fwnode_property_present(child, "retain-state-shutdown"))
168			led.retain_state_shutdown = 1;
169		if (fwnode_property_present(child, "panic-indicator"))
170			led.panic_indicator = 1;
171
172		ret = create_gpio_led(&led, led_dat, dev, child, NULL);
173		if (ret < 0) {
174			fwnode_handle_put(child);
175			return ERR_PTR(ret);
176		}
177		/* Set gpiod label to match the corresponding LED name. */
178		gpiod_set_consumer_name(led_dat->gpiod,
179					led_dat->cdev.dev->kobj.name);
180		priv->num_leds++;
181	}
182
183	return priv;
184}
185
186static const struct of_device_id of_gpio_leds_match[] = {
187	{ .compatible = "gpio-leds", },
188	{},
189};
190
191MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
192
193static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
194					    const struct gpio_led *template)
195{
196	struct gpio_desc *gpiod;
197	unsigned long flags = GPIOF_OUT_INIT_LOW;
198	int ret;
199
200	/*
201	 * This means the LED does not come from the device tree
202	 * or ACPI, so let's try just getting it by index from the
203	 * device, this will hit the board file, if any and get
204	 * the GPIO from there.
205	 */
206	gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOD_OUT_LOW);
207	if (!IS_ERR(gpiod)) {
208		gpiod_set_consumer_name(gpiod, template->name);
209		return gpiod;
210	}
211	if (PTR_ERR(gpiod) != -ENOENT)
212		return gpiod;
213
214	/*
215	 * This is the legacy code path for platform code that
216	 * still uses GPIO numbers. Ultimately we would like to get
217	 * rid of this block completely.
218	 */
219
220	/* skip leds that aren't available */
221	if (!gpio_is_valid(template->gpio))
222		return ERR_PTR(-ENOENT);
223
224	if (template->active_low)
225		flags |= GPIOF_ACTIVE_LOW;
226
227	ret = devm_gpio_request_one(dev, template->gpio, flags,
228				    template->name);
229	if (ret < 0)
230		return ERR_PTR(ret);
231
232	gpiod = gpio_to_desc(template->gpio);
233	if (!gpiod)
234		return ERR_PTR(-EINVAL);
235
236	return gpiod;
237}
238
239static int gpio_led_probe(struct platform_device *pdev)
240{
241	struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
242	struct gpio_leds_priv *priv;
243	int i, ret = 0;
244
245	if (pdata && pdata->num_leds) {
246		priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, pdata->num_leds),
247				    GFP_KERNEL);
248		if (!priv)
249			return -ENOMEM;
250
251		priv->num_leds = pdata->num_leds;
252		for (i = 0; i < priv->num_leds; i++) {
253			const struct gpio_led *template = &pdata->leds[i];
254			struct gpio_led_data *led_dat = &priv->leds[i];
255
256			if (template->gpiod)
257				led_dat->gpiod = template->gpiod;
258			else
259				led_dat->gpiod =
260					gpio_led_get_gpiod(&pdev->dev,
261							   i, template);
262			if (IS_ERR(led_dat->gpiod)) {
263				dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
264					 template->gpio, template->name);
265				continue;
266			}
267
268			ret = create_gpio_led(template, led_dat,
269					      &pdev->dev, NULL,
270					      pdata->gpio_blink_set);
271			if (ret < 0)
272				return ret;
273		}
274	} else {
275		priv = gpio_leds_create(pdev);
276		if (IS_ERR(priv))
277			return PTR_ERR(priv);
278	}
279
280	platform_set_drvdata(pdev, priv);
281
282	return 0;
283}
284
285static void gpio_led_shutdown(struct platform_device *pdev)
286{
287	struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
288	int i;
289
290	for (i = 0; i < priv->num_leds; i++) {
291		struct gpio_led_data *led = &priv->leds[i];
292
293		if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
294			gpio_led_set(&led->cdev, LED_OFF);
295	}
296}
297
298static struct platform_driver gpio_led_driver = {
299	.probe		= gpio_led_probe,
300	.shutdown	= gpio_led_shutdown,
301	.driver		= {
302		.name	= "leds-gpio",
303		.of_match_table = of_gpio_leds_match,
304	},
305};
306
307module_platform_driver(gpio_led_driver);
308
309MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
310MODULE_DESCRIPTION("GPIO LED driver");
311MODULE_LICENSE("GPL");
312MODULE_ALIAS("platform:leds-gpio");
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * LEDs driver for GPIOs
  4 *
  5 * Copyright (C) 2007 8D Technologies inc.
  6 * Raphael Assenat <raph@8d.com>
  7 * Copyright (C) 2008 Freescale Semiconductor, Inc.
  8 */
  9#include <linux/err.h>
 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>
 15#include <linux/of.h>
 16#include <linux/platform_device.h>
 17#include <linux/property.h>
 18#include <linux/slab.h>
 
 19
 20struct gpio_led_data {
 21	struct led_classdev cdev;
 22	struct gpio_desc *gpiod;
 23	u8 can_sleep;
 24	u8 blinking;
 25	gpio_blink_set_t platform_gpio_blink_set;
 26};
 27
 28static inline struct gpio_led_data *
 29			cdev_to_gpio_led_data(struct led_classdev *led_cdev)
 30{
 31	return container_of(led_cdev, struct gpio_led_data, cdev);
 32}
 33
 34static void gpio_led_set(struct led_classdev *led_cdev,
 35	enum led_brightness value)
 36{
 37	struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
 38	int level;
 39
 40	if (value == LED_OFF)
 41		level = 0;
 42	else
 43		level = 1;
 44
 45	if (led_dat->blinking) {
 46		led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
 47						 NULL, NULL);
 48		led_dat->blinking = 0;
 49	} else {
 50		if (led_dat->can_sleep)
 51			gpiod_set_value_cansleep(led_dat->gpiod, level);
 52		else
 53			gpiod_set_value(led_dat->gpiod, level);
 54	}
 55}
 56
 57static int gpio_led_set_blocking(struct led_classdev *led_cdev,
 58	enum led_brightness value)
 59{
 60	gpio_led_set(led_cdev, value);
 61	return 0;
 62}
 63
 64static int gpio_blink_set(struct led_classdev *led_cdev,
 65	unsigned long *delay_on, unsigned long *delay_off)
 66{
 67	struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
 68
 69	led_dat->blinking = 1;
 70	return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
 71						delay_on, delay_off);
 72}
 73
 74static int create_gpio_led(const struct gpio_led *template,
 75	struct gpio_led_data *led_dat, struct device *parent,
 76	struct fwnode_handle *fwnode, gpio_blink_set_t blink_set)
 77{
 78	struct led_init_data init_data = {};
 79	int ret, state;
 80
 81	led_dat->cdev.default_trigger = template->default_trigger;
 82	led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
 83	if (!led_dat->can_sleep)
 84		led_dat->cdev.brightness_set = gpio_led_set;
 85	else
 86		led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
 87	led_dat->blinking = 0;
 88	if (blink_set) {
 89		led_dat->platform_gpio_blink_set = blink_set;
 90		led_dat->cdev.blink_set = gpio_blink_set;
 91	}
 92	if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
 93		state = gpiod_get_value_cansleep(led_dat->gpiod);
 94		if (state < 0)
 95			return state;
 96	} else {
 97		state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
 98	}
 99	led_dat->cdev.brightness = state;
100	led_dat->cdev.max_brightness = 1;
101	if (!template->retain_state_suspended)
102		led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
103	if (template->panic_indicator)
104		led_dat->cdev.flags |= LED_PANIC_INDICATOR;
105	if (template->retain_state_shutdown)
106		led_dat->cdev.flags |= LED_RETAIN_AT_SHUTDOWN;
107
108	ret = gpiod_direction_output(led_dat->gpiod, state);
109	if (ret < 0)
110		return ret;
111
112	if (template->name) {
113		led_dat->cdev.name = template->name;
114		ret = devm_led_classdev_register(parent, &led_dat->cdev);
115	} else {
116		init_data.fwnode = fwnode;
117		ret = devm_led_classdev_register_ext(parent, &led_dat->cdev,
118						     &init_data);
119	}
120
121	return ret;
122}
123
124struct gpio_leds_priv {
125	int num_leds;
126	struct gpio_led_data leds[];
127};
128
129static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
130{
131	struct device *dev = &pdev->dev;
132	struct fwnode_handle *child;
133	struct gpio_leds_priv *priv;
134	int count, ret;
135
136	count = device_get_child_node_count(dev);
137	if (!count)
138		return ERR_PTR(-ENODEV);
139
140	priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
141	if (!priv)
142		return ERR_PTR(-ENOMEM);
143
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
149		/*
150		 * Acquire gpiod from DT with uninitialized label, which
151		 * will be updated after LED class device is registered,
152		 * Only then the final LED name is known.
153		 */
154		led.gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL, child,
155							     GPIOD_ASIS,
156							     NULL);
157		if (IS_ERR(led.gpiod)) {
158			fwnode_handle_put(child);
159			return ERR_CAST(led.gpiod);
160		}
161
162		led_dat->gpiod = led.gpiod;
163
164		if (!fwnode_property_read_string(child, "default-state",
165						 &state)) {
166			if (!strcmp(state, "keep"))
167				led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
168			else if (!strcmp(state, "on"))
169				led.default_state = LEDS_GPIO_DEFSTATE_ON;
170			else
171				led.default_state = LEDS_GPIO_DEFSTATE_OFF;
172		}
173
174		if (fwnode_property_present(child, "retain-state-suspended"))
175			led.retain_state_suspended = 1;
176		if (fwnode_property_present(child, "retain-state-shutdown"))
177			led.retain_state_shutdown = 1;
178		if (fwnode_property_present(child, "panic-indicator"))
179			led.panic_indicator = 1;
180
181		ret = create_gpio_led(&led, led_dat, dev, child, NULL);
182		if (ret < 0) {
183			fwnode_handle_put(child);
184			return ERR_PTR(ret);
185		}
186		/* Set gpiod label to match the corresponding LED name. */
187		gpiod_set_consumer_name(led_dat->gpiod,
188					led_dat->cdev.dev->kobj.name);
189		priv->num_leds++;
190	}
191
192	return priv;
193}
194
195static const struct of_device_id of_gpio_leds_match[] = {
196	{ .compatible = "gpio-leds", },
197	{},
198};
199
200MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
201
202static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
203					    const struct gpio_led *template)
204{
205	struct gpio_desc *gpiod;
206	unsigned long flags = GPIOF_OUT_INIT_LOW;
207	int ret;
208
209	/*
210	 * This means the LED does not come from the device tree
211	 * or ACPI, so let's try just getting it by index from the
212	 * device, this will hit the board file, if any and get
213	 * the GPIO from there.
214	 */
215	gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOD_OUT_LOW);
216	if (!IS_ERR(gpiod)) {
217		gpiod_set_consumer_name(gpiod, template->name);
218		return gpiod;
219	}
220	if (PTR_ERR(gpiod) != -ENOENT)
221		return gpiod;
222
223	/*
224	 * This is the legacy code path for platform code that
225	 * still uses GPIO numbers. Ultimately we would like to get
226	 * rid of this block completely.
227	 */
228
229	/* skip leds that aren't available */
230	if (!gpio_is_valid(template->gpio))
231		return ERR_PTR(-ENOENT);
232
233	if (template->active_low)
234		flags |= GPIOF_ACTIVE_LOW;
235
236	ret = devm_gpio_request_one(dev, template->gpio, flags,
237				    template->name);
238	if (ret < 0)
239		return ERR_PTR(ret);
240
241	gpiod = gpio_to_desc(template->gpio);
242	if (!gpiod)
243		return ERR_PTR(-EINVAL);
244
245	return gpiod;
246}
247
248static int gpio_led_probe(struct platform_device *pdev)
249{
250	struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
251	struct gpio_leds_priv *priv;
252	int i, ret = 0;
253
254	if (pdata && pdata->num_leds) {
255		priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, pdata->num_leds),
256				    GFP_KERNEL);
257		if (!priv)
258			return -ENOMEM;
259
260		priv->num_leds = pdata->num_leds;
261		for (i = 0; i < priv->num_leds; i++) {
262			const struct gpio_led *template = &pdata->leds[i];
263			struct gpio_led_data *led_dat = &priv->leds[i];
264
265			if (template->gpiod)
266				led_dat->gpiod = template->gpiod;
267			else
268				led_dat->gpiod =
269					gpio_led_get_gpiod(&pdev->dev,
270							   i, template);
271			if (IS_ERR(led_dat->gpiod)) {
272				dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
273					 template->gpio, template->name);
274				continue;
275			}
276
277			ret = create_gpio_led(template, led_dat,
278					      &pdev->dev, NULL,
279					      pdata->gpio_blink_set);
280			if (ret < 0)
281				return ret;
282		}
283	} else {
284		priv = gpio_leds_create(pdev);
285		if (IS_ERR(priv))
286			return PTR_ERR(priv);
287	}
288
289	platform_set_drvdata(pdev, priv);
290
291	return 0;
292}
293
294static void gpio_led_shutdown(struct platform_device *pdev)
295{
296	struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
297	int i;
298
299	for (i = 0; i < priv->num_leds; i++) {
300		struct gpio_led_data *led = &priv->leds[i];
301
302		if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
303			gpio_led_set(&led->cdev, LED_OFF);
304	}
305}
306
307static struct platform_driver gpio_led_driver = {
308	.probe		= gpio_led_probe,
309	.shutdown	= gpio_led_shutdown,
310	.driver		= {
311		.name	= "leds-gpio",
312		.of_match_table = of_gpio_leds_match,
313	},
314};
315
316module_platform_driver(gpio_led_driver);
317
318MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
319MODULE_DESCRIPTION("GPIO LED driver");
320MODULE_LICENSE("GPL");
321MODULE_ALIAS("platform:leds-gpio");