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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/container_of.h>
10#include <linux/device.h>
11#include <linux/err.h>
12#include <linux/gpio.h>
13#include <linux/gpio/consumer.h>
14#include <linux/leds.h>
15#include <linux/mod_devicetable.h>
16#include <linux/module.h>
17#include <linux/overflow.h>
18#include <linux/pinctrl/consumer.h>
19#include <linux/platform_device.h>
20#include <linux/property.h>
21#include <linux/slab.h>
22#include <linux/types.h>
23
24#include "leds.h"
25
26struct gpio_led_data {
27 struct led_classdev cdev;
28 struct gpio_desc *gpiod;
29 u8 can_sleep;
30 u8 blinking;
31 gpio_blink_set_t platform_gpio_blink_set;
32};
33
34static inline struct gpio_led_data *
35 cdev_to_gpio_led_data(struct led_classdev *led_cdev)
36{
37 return container_of(led_cdev, struct gpio_led_data, cdev);
38}
39
40static void gpio_led_set(struct led_classdev *led_cdev,
41 enum led_brightness value)
42{
43 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
44 int level;
45
46 if (value == LED_OFF)
47 level = 0;
48 else
49 level = 1;
50
51 if (led_dat->blinking) {
52 led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
53 NULL, NULL);
54 led_dat->blinking = 0;
55 } else {
56 if (led_dat->can_sleep)
57 gpiod_set_value_cansleep(led_dat->gpiod, level);
58 else
59 gpiod_set_value(led_dat->gpiod, level);
60 }
61}
62
63static int gpio_led_set_blocking(struct led_classdev *led_cdev,
64 enum led_brightness value)
65{
66 gpio_led_set(led_cdev, value);
67 return 0;
68}
69
70static int gpio_blink_set(struct led_classdev *led_cdev,
71 unsigned long *delay_on, unsigned long *delay_off)
72{
73 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
74
75 led_dat->blinking = 1;
76 return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
77 delay_on, delay_off);
78}
79
80static int create_gpio_led(const struct gpio_led *template,
81 struct gpio_led_data *led_dat, struct device *parent,
82 struct fwnode_handle *fwnode, gpio_blink_set_t blink_set)
83{
84 struct led_init_data init_data = {};
85 struct pinctrl *pinctrl;
86 int ret, state;
87
88 led_dat->cdev.default_trigger = template->default_trigger;
89 led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
90 if (!led_dat->can_sleep)
91 led_dat->cdev.brightness_set = gpio_led_set;
92 else
93 led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
94 led_dat->blinking = 0;
95 if (blink_set) {
96 led_dat->platform_gpio_blink_set = blink_set;
97 led_dat->cdev.blink_set = gpio_blink_set;
98 }
99 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
100 state = gpiod_get_value_cansleep(led_dat->gpiod);
101 if (state < 0)
102 return state;
103 } else {
104 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
105 }
106 led_dat->cdev.brightness = state;
107 led_dat->cdev.max_brightness = 1;
108 if (!template->retain_state_suspended)
109 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
110 if (template->panic_indicator)
111 led_dat->cdev.flags |= LED_PANIC_INDICATOR;
112 if (template->retain_state_shutdown)
113 led_dat->cdev.flags |= LED_RETAIN_AT_SHUTDOWN;
114
115 ret = gpiod_direction_output(led_dat->gpiod, state);
116 if (ret < 0)
117 return ret;
118
119 if (template->name) {
120 led_dat->cdev.name = template->name;
121 ret = devm_led_classdev_register(parent, &led_dat->cdev);
122 } else {
123 init_data.fwnode = fwnode;
124 ret = devm_led_classdev_register_ext(parent, &led_dat->cdev,
125 &init_data);
126 }
127
128 if (ret)
129 return ret;
130
131 pinctrl = devm_pinctrl_get_select_default(led_dat->cdev.dev);
132 ret = PTR_ERR_OR_ZERO(pinctrl);
133 /* pinctrl-%d not present, not an error */
134 if (ret == -ENODEV)
135 ret = 0;
136 if (ret) {
137 dev_warn(led_dat->cdev.dev, "Failed to select %pfw pinctrl: %d\n",
138 fwnode, ret);
139 }
140
141 return ret;
142}
143
144struct gpio_leds_priv {
145 int num_leds;
146 struct gpio_led_data leds[] __counted_by(num_leds);
147};
148
149static struct gpio_leds_priv *gpio_leds_create(struct device *dev)
150{
151 struct fwnode_handle *child;
152 struct gpio_leds_priv *priv;
153 int count, ret;
154
155 count = device_get_child_node_count(dev);
156 if (!count)
157 return ERR_PTR(-ENODEV);
158
159 priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
160 if (!priv)
161 return ERR_PTR(-ENOMEM);
162
163 device_for_each_child_node(dev, child) {
164 struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
165 struct gpio_led led = {};
166
167 /*
168 * Acquire gpiod from DT with uninitialized label, which
169 * will be updated after LED class device is registered,
170 * Only then the final LED name is known.
171 */
172 led.gpiod = devm_fwnode_gpiod_get(dev, child, NULL, GPIOD_ASIS,
173 NULL);
174 if (IS_ERR(led.gpiod)) {
175 dev_err_probe(dev, PTR_ERR(led.gpiod), "Failed to get GPIO '%pfw'\n",
176 child);
177 fwnode_handle_put(child);
178 return ERR_CAST(led.gpiod);
179 }
180
181 led_dat->gpiod = led.gpiod;
182
183 led.default_state = led_init_default_state_get(child);
184
185 if (fwnode_property_present(child, "retain-state-suspended"))
186 led.retain_state_suspended = 1;
187 if (fwnode_property_present(child, "retain-state-shutdown"))
188 led.retain_state_shutdown = 1;
189 if (fwnode_property_present(child, "panic-indicator"))
190 led.panic_indicator = 1;
191
192 ret = create_gpio_led(&led, led_dat, dev, child, NULL);
193 if (ret < 0) {
194 fwnode_handle_put(child);
195 return ERR_PTR(ret);
196 }
197 /* Set gpiod label to match the corresponding LED name. */
198 gpiod_set_consumer_name(led_dat->gpiod,
199 led_dat->cdev.dev->kobj.name);
200 priv->num_leds++;
201 }
202
203 return priv;
204}
205
206static const struct of_device_id of_gpio_leds_match[] = {
207 { .compatible = "gpio-leds", },
208 {},
209};
210
211MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
212
213static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
214 const struct gpio_led *template)
215{
216 struct gpio_desc *gpiod;
217 unsigned long flags = GPIOF_OUT_INIT_LOW;
218 int ret;
219
220 /*
221 * This means the LED does not come from the device tree
222 * or ACPI, so let's try just getting it by index from the
223 * device, this will hit the board file, if any and get
224 * the GPIO from there.
225 */
226 gpiod = devm_gpiod_get_index_optional(dev, NULL, idx, GPIOD_OUT_LOW);
227 if (IS_ERR(gpiod))
228 return gpiod;
229 if (gpiod) {
230 gpiod_set_consumer_name(gpiod, template->name);
231 return gpiod;
232 }
233
234 /*
235 * This is the legacy code path for platform code that
236 * still uses GPIO numbers. Ultimately we would like to get
237 * rid of this block completely.
238 */
239
240 /* skip leds that aren't available */
241 if (!gpio_is_valid(template->gpio))
242 return ERR_PTR(-ENOENT);
243
244 if (template->active_low)
245 flags |= GPIOF_ACTIVE_LOW;
246
247 ret = devm_gpio_request_one(dev, template->gpio, flags,
248 template->name);
249 if (ret < 0)
250 return ERR_PTR(ret);
251
252 gpiod = gpio_to_desc(template->gpio);
253 if (!gpiod)
254 return ERR_PTR(-EINVAL);
255
256 return gpiod;
257}
258
259static int gpio_led_probe(struct platform_device *pdev)
260{
261 struct device *dev = &pdev->dev;
262 struct gpio_led_platform_data *pdata = dev_get_platdata(dev);
263 struct gpio_leds_priv *priv;
264 int i, ret;
265
266 if (pdata && pdata->num_leds) {
267 priv = devm_kzalloc(dev, struct_size(priv, leds, pdata->num_leds), GFP_KERNEL);
268 if (!priv)
269 return -ENOMEM;
270
271 priv->num_leds = pdata->num_leds;
272 for (i = 0; i < priv->num_leds; i++) {
273 const struct gpio_led *template = &pdata->leds[i];
274 struct gpio_led_data *led_dat = &priv->leds[i];
275
276 if (template->gpiod)
277 led_dat->gpiod = template->gpiod;
278 else
279 led_dat->gpiod =
280 gpio_led_get_gpiod(dev, i, template);
281 if (IS_ERR(led_dat->gpiod)) {
282 dev_info(dev, "Skipping unavailable LED gpio %d (%s)\n",
283 template->gpio, template->name);
284 continue;
285 }
286
287 ret = create_gpio_led(template, led_dat, dev, NULL,
288 pdata->gpio_blink_set);
289 if (ret < 0)
290 return ret;
291 }
292 } else {
293 priv = gpio_leds_create(dev);
294 if (IS_ERR(priv))
295 return PTR_ERR(priv);
296 }
297
298 platform_set_drvdata(pdev, priv);
299
300 return 0;
301}
302
303static void gpio_led_shutdown(struct platform_device *pdev)
304{
305 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
306 int i;
307
308 for (i = 0; i < priv->num_leds; i++) {
309 struct gpio_led_data *led = &priv->leds[i];
310
311 if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
312 gpio_led_set(&led->cdev, LED_OFF);
313 }
314}
315
316static struct platform_driver gpio_led_driver = {
317 .probe = gpio_led_probe,
318 .shutdown = gpio_led_shutdown,
319 .driver = {
320 .name = "leds-gpio",
321 .of_match_table = of_gpio_leds_match,
322 },
323};
324
325module_platform_driver(gpio_led_driver);
326
327MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
328MODULE_DESCRIPTION("GPIO LED driver");
329MODULE_LICENSE("GPL");
330MODULE_ALIAS("platform:leds-gpio");
1/*
2 * LEDs driver for GPIOs
3 *
4 * Copyright (C) 2007 8D Technologies inc.
5 * Raphael Assenat <raph@8d.com>
6 * Copyright (C) 2008 Freescale Semiconductor, Inc.
7 *
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.
11 *
12 */
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>
19#include <linux/of.h>
20#include <linux/platform_device.h>
21#include <linux/property.h>
22#include <linux/slab.h>
23
24struct gpio_led_data {
25 struct led_classdev cdev;
26 struct gpio_desc *gpiod;
27 u8 can_sleep;
28 u8 blinking;
29 gpio_blink_set_t platform_gpio_blink_set;
30};
31
32static inline struct gpio_led_data *
33 cdev_to_gpio_led_data(struct led_classdev *led_cdev)
34{
35 return container_of(led_cdev, struct gpio_led_data, cdev);
36}
37
38static void gpio_led_set(struct led_classdev *led_cdev,
39 enum led_brightness value)
40{
41 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
42 int level;
43
44 if (value == LED_OFF)
45 level = 0;
46 else
47 level = 1;
48
49 if (led_dat->blinking) {
50 led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
51 NULL, NULL);
52 led_dat->blinking = 0;
53 } else {
54 if (led_dat->can_sleep)
55 gpiod_set_value_cansleep(led_dat->gpiod, level);
56 else
57 gpiod_set_value(led_dat->gpiod, level);
58 }
59}
60
61static int gpio_led_set_blocking(struct led_classdev *led_cdev,
62 enum led_brightness value)
63{
64 gpio_led_set(led_cdev, value);
65 return 0;
66}
67
68static int gpio_blink_set(struct led_classdev *led_cdev,
69 unsigned long *delay_on, unsigned long *delay_off)
70{
71 struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
72
73 led_dat->blinking = 1;
74 return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
75 delay_on, delay_off);
76}
77
78static int create_gpio_led(const struct gpio_led *template,
79 struct gpio_led_data *led_dat, struct device *parent,
80 gpio_blink_set_t blink_set)
81{
82 int ret, state;
83
84 led_dat->gpiod = template->gpiod;
85 if (!led_dat->gpiod) {
86 /*
87 * This is the legacy code path for platform code that
88 * still uses GPIO numbers. Ultimately we would like to get
89 * rid of this block completely.
90 */
91 unsigned long flags = GPIOF_OUT_INIT_LOW;
92
93 /* skip leds that aren't available */
94 if (!gpio_is_valid(template->gpio)) {
95 dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n",
96 template->gpio, template->name);
97 return 0;
98 }
99
100 if (template->active_low)
101 flags |= GPIOF_ACTIVE_LOW;
102
103 ret = devm_gpio_request_one(parent, template->gpio, flags,
104 template->name);
105 if (ret < 0)
106 return ret;
107
108 led_dat->gpiod = gpio_to_desc(template->gpio);
109 if (!led_dat->gpiod)
110 return -EINVAL;
111 }
112
113 led_dat->cdev.name = template->name;
114 led_dat->cdev.default_trigger = template->default_trigger;
115 led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
116 if (!led_dat->can_sleep)
117 led_dat->cdev.brightness_set = gpio_led_set;
118 else
119 led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
120 led_dat->blinking = 0;
121 if (blink_set) {
122 led_dat->platform_gpio_blink_set = blink_set;
123 led_dat->cdev.blink_set = gpio_blink_set;
124 }
125 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
126 state = gpiod_get_value_cansleep(led_dat->gpiod);
127 if (state < 0)
128 return state;
129 } else {
130 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
131 }
132 led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
133 if (!template->retain_state_suspended)
134 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
135 if (template->panic_indicator)
136 led_dat->cdev.flags |= LED_PANIC_INDICATOR;
137
138 ret = gpiod_direction_output(led_dat->gpiod, state);
139 if (ret < 0)
140 return ret;
141
142 return devm_led_classdev_register(parent, &led_dat->cdev);
143}
144
145struct gpio_leds_priv {
146 int num_leds;
147 struct gpio_led_data leds[];
148};
149
150static inline int sizeof_gpio_leds_priv(int num_leds)
151{
152 return sizeof(struct gpio_leds_priv) +
153 (sizeof(struct gpio_led_data) * num_leds);
154}
155
156static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
157{
158 struct device *dev = &pdev->dev;
159 struct fwnode_handle *child;
160 struct gpio_leds_priv *priv;
161 int count, ret;
162
163 count = device_get_child_node_count(dev);
164 if (!count)
165 return ERR_PTR(-ENODEV);
166
167 priv = devm_kzalloc(dev, sizeof_gpio_leds_priv(count), GFP_KERNEL);
168 if (!priv)
169 return ERR_PTR(-ENOMEM);
170
171 device_for_each_child_node(dev, child) {
172 struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
173 struct gpio_led led = {};
174 const char *state = NULL;
175 struct device_node *np = to_of_node(child);
176
177 led.gpiod = devm_get_gpiod_from_child(dev, NULL, child);
178 if (IS_ERR(led.gpiod)) {
179 fwnode_handle_put(child);
180 return ERR_CAST(led.gpiod);
181 }
182
183 ret = fwnode_property_read_string(child, "label", &led.name);
184 if (ret && IS_ENABLED(CONFIG_OF) && np)
185 led.name = np->name;
186 if (!led.name) {
187 fwnode_handle_put(child);
188 return ERR_PTR(-EINVAL);
189 }
190
191 fwnode_property_read_string(child, "linux,default-trigger",
192 &led.default_trigger);
193
194 if (!fwnode_property_read_string(child, "default-state",
195 &state)) {
196 if (!strcmp(state, "keep"))
197 led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
198 else if (!strcmp(state, "on"))
199 led.default_state = LEDS_GPIO_DEFSTATE_ON;
200 else
201 led.default_state = LEDS_GPIO_DEFSTATE_OFF;
202 }
203
204 if (fwnode_property_present(child, "retain-state-suspended"))
205 led.retain_state_suspended = 1;
206 if (fwnode_property_present(child, "panic-indicator"))
207 led.panic_indicator = 1;
208
209 ret = create_gpio_led(&led, led_dat, dev, NULL);
210 if (ret < 0) {
211 fwnode_handle_put(child);
212 return ERR_PTR(ret);
213 }
214 led_dat->cdev.dev->of_node = np;
215 priv->num_leds++;
216 }
217
218 return priv;
219}
220
221static const struct of_device_id of_gpio_leds_match[] = {
222 { .compatible = "gpio-leds", },
223 {},
224};
225
226MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
227
228static int gpio_led_probe(struct platform_device *pdev)
229{
230 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
231 struct gpio_leds_priv *priv;
232 int i, ret = 0;
233
234 if (pdata && pdata->num_leds) {
235 priv = devm_kzalloc(&pdev->dev,
236 sizeof_gpio_leds_priv(pdata->num_leds),
237 GFP_KERNEL);
238 if (!priv)
239 return -ENOMEM;
240
241 priv->num_leds = pdata->num_leds;
242 for (i = 0; i < priv->num_leds; i++) {
243 ret = create_gpio_led(&pdata->leds[i],
244 &priv->leds[i],
245 &pdev->dev, pdata->gpio_blink_set);
246 if (ret < 0)
247 return ret;
248 }
249 } else {
250 priv = gpio_leds_create(pdev);
251 if (IS_ERR(priv))
252 return PTR_ERR(priv);
253 }
254
255 platform_set_drvdata(pdev, priv);
256
257 return 0;
258}
259
260static void gpio_led_shutdown(struct platform_device *pdev)
261{
262 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
263 int i;
264
265 for (i = 0; i < priv->num_leds; i++) {
266 struct gpio_led_data *led = &priv->leds[i];
267
268 gpio_led_set(&led->cdev, LED_OFF);
269 }
270}
271
272static struct platform_driver gpio_led_driver = {
273 .probe = gpio_led_probe,
274 .shutdown = gpio_led_shutdown,
275 .driver = {
276 .name = "leds-gpio",
277 .of_match_table = of_gpio_leds_match,
278 },
279};
280
281module_platform_driver(gpio_led_driver);
282
283MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
284MODULE_DESCRIPTION("GPIO LED driver");
285MODULE_LICENSE("GPL");
286MODULE_ALIAS("platform:leds-gpio");