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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
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151
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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 led.default_state = led_init_default_state_get(child);
165
166 if (fwnode_property_present(child, "retain-state-suspended"))
167 led.retain_state_suspended = 1;
168 if (fwnode_property_present(child, "retain-state-shutdown"))
169 led.retain_state_shutdown = 1;
170 if (fwnode_property_present(child, "panic-indicator"))
171 led.panic_indicator = 1;
172
173 ret = create_gpio_led(&led, led_dat, dev, child, NULL);
174 if (ret < 0) {
175 fwnode_handle_put(child);
176 return ERR_PTR(ret);
177 }
178
179 gpiod_set_consumer_name(led_dat->gpiod,
180 led_dat->cdev.dev->kobj.name);
181 priv->num_leds++;
182 }
183
184 return priv;
185}
186
187static const struct of_device_id of_gpio_leds_match[] = {
188 { .compatible = "gpio-leds", },
189 {},
190};
191
192MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
193
194static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
195 const struct gpio_led *template)
196{
197 struct gpio_desc *gpiod;
198 unsigned long flags = GPIOF_OUT_INIT_LOW;
199 int ret;
200
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206
207 gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOD_OUT_LOW);
208 if (!IS_ERR(gpiod)) {
209 gpiod_set_consumer_name(gpiod, template->name);
210 return gpiod;
211 }
212 if (PTR_ERR(gpiod) != -ENOENT)
213 return gpiod;
214
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219
220
221
222 if (!gpio_is_valid(template->gpio))
223 return ERR_PTR(-ENOENT);
224
225 if (template->active_low)
226 flags |= GPIOF_ACTIVE_LOW;
227
228 ret = devm_gpio_request_one(dev, template->gpio, flags,
229 template->name);
230 if (ret < 0)
231 return ERR_PTR(ret);
232
233 gpiod = gpio_to_desc(template->gpio);
234 if (!gpiod)
235 return ERR_PTR(-EINVAL);
236
237 return gpiod;
238}
239
240static int gpio_led_probe(struct platform_device *pdev)
241{
242 struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
243 struct gpio_leds_priv *priv;
244 int i, ret = 0;
245
246 if (pdata && pdata->num_leds) {
247 priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, pdata->num_leds),
248 GFP_KERNEL);
249 if (!priv)
250 return -ENOMEM;
251
252 priv->num_leds = pdata->num_leds;
253 for (i = 0; i < priv->num_leds; i++) {
254 const struct gpio_led *template = &pdata->leds[i];
255 struct gpio_led_data *led_dat = &priv->leds[i];
256
257 if (template->gpiod)
258 led_dat->gpiod = template->gpiod;
259 else
260 led_dat->gpiod =
261 gpio_led_get_gpiod(&pdev->dev,
262 i, template);
263 if (IS_ERR(led_dat->gpiod)) {
264 dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
265 template->gpio, template->name);
266 continue;
267 }
268
269 ret = create_gpio_led(template, led_dat,
270 &pdev->dev, NULL,
271 pdata->gpio_blink_set);
272 if (ret < 0)
273 return ret;
274 }
275 } else {
276 priv = gpio_leds_create(pdev);
277 if (IS_ERR(priv))
278 return PTR_ERR(priv);
279 }
280
281 platform_set_drvdata(pdev, priv);
282
283 return 0;
284}
285
286static void gpio_led_shutdown(struct platform_device *pdev)
287{
288 struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
289 int i;
290
291 for (i = 0; i < priv->num_leds; i++) {
292 struct gpio_led_data *led = &priv->leds[i];
293
294 if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
295 gpio_led_set(&led->cdev, LED_OFF);
296 }
297}
298
299static struct platform_driver gpio_led_driver = {
300 .probe = gpio_led_probe,
301 .shutdown = gpio_led_shutdown,
302 .driver = {
303 .name = "leds-gpio",
304 .of_match_table = of_gpio_leds_match,
305 },
306};
307
308module_platform_driver(gpio_led_driver);
309
310MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
311MODULE_DESCRIPTION("GPIO LED driver");
312MODULE_LICENSE("GPL");
313MODULE_ALIAS("platform:leds-gpio");
314
