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13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/platform_device.h>
16#include <linux/leds.h>
17#include <linux/workqueue.h>
18
19#include <asm/gpio.h>
20
21struct gpio_led_data {
22 struct led_classdev cdev;
23 unsigned gpio;
24 struct work_struct work;
25 u8 new_level;
26 u8 can_sleep;
27 u8 active_low;
28 int (*platform_gpio_blink_set)(unsigned gpio,
29 unsigned long *delay_on, unsigned long *delay_off);
30};
31
32static void gpio_led_work(struct work_struct *work)
33{
34 struct gpio_led_data *led_dat =
35 container_of(work, struct gpio_led_data, work);
36
37 gpio_set_value_cansleep(led_dat->gpio, led_dat->new_level);
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 =
44 container_of(led_cdev, struct gpio_led_data, cdev);
45 int level;
46
47 if (value == LED_OFF)
48 level = 0;
49 else
50 level = 1;
51
52 if (led_dat->active_low)
53 level = !level;
54
55
56
57
58
59 if (led_dat->can_sleep) {
60 led_dat->new_level = level;
61 schedule_work(&led_dat->work);
62 } else
63 gpio_set_value(led_dat->gpio, level);
64}
65
66static int gpio_blink_set(struct led_classdev *led_cdev,
67 unsigned long *delay_on, unsigned long *delay_off)
68{
69 struct gpio_led_data *led_dat =
70 container_of(led_cdev, struct gpio_led_data, cdev);
71
72 return led_dat->platform_gpio_blink_set(led_dat->gpio, delay_on, delay_off);
73}
74
75static int __devinit create_gpio_led(const struct gpio_led *template,
76 struct gpio_led_data *led_dat, struct device *parent,
77 int (*blink_set)(unsigned, unsigned long *, unsigned long *))
78{
79 int ret, state;
80
81 led_dat->gpio = -1;
82
83
84 if (!gpio_is_valid(template->gpio)) {
85 printk(KERN_INFO "Skipping unavailable LED gpio %d (%s)\n",
86 template->gpio, template->name);
87 return 0;
88 }
89
90 ret = gpio_request(template->gpio, template->name);
91 if (ret < 0)
92 return ret;
93
94 led_dat->cdev.name = template->name;
95 led_dat->cdev.default_trigger = template->default_trigger;
96 led_dat->gpio = template->gpio;
97 led_dat->can_sleep = gpio_cansleep(template->gpio);
98 led_dat->active_low = template->active_low;
99 if (blink_set) {
100 led_dat->platform_gpio_blink_set = blink_set;
101 led_dat->cdev.blink_set = gpio_blink_set;
102 }
103 led_dat->cdev.brightness_set = gpio_led_set;
104 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP)
105 state = !!gpio_get_value(led_dat->gpio) ^ led_dat->active_low;
106 else
107 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
108 led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
109 if (!template->retain_state_suspended)
110 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
111
112 ret = gpio_direction_output(led_dat->gpio, led_dat->active_low ^ state);
113 if (ret < 0)
114 goto err;
115
116 INIT_WORK(&led_dat->work, gpio_led_work);
117
118 ret = led_classdev_register(parent, &led_dat->cdev);
119 if (ret < 0)
120 goto err;
121
122 return 0;
123err:
124 gpio_free(led_dat->gpio);
125 return ret;
126}
127
128static void delete_gpio_led(struct gpio_led_data *led)
129{
130 if (!gpio_is_valid(led->gpio))
131 return;
132 led_classdev_unregister(&led->cdev);
133 cancel_work_sync(&led->work);
134 gpio_free(led->gpio);
135}
136
137#ifdef CONFIG_LEDS_GPIO_PLATFORM
138static int __devinit gpio_led_probe(struct platform_device *pdev)
139{
140 struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
141 struct gpio_led_data *leds_data;
142 int i, ret = 0;
143
144 if (!pdata)
145 return -EBUSY;
146
147 leds_data = kzalloc(sizeof(struct gpio_led_data) * pdata->num_leds,
148 GFP_KERNEL);
149 if (!leds_data)
150 return -ENOMEM;
151
152 for (i = 0; i < pdata->num_leds; i++) {
153 ret = create_gpio_led(&pdata->leds[i], &leds_data[i],
154 &pdev->dev, pdata->gpio_blink_set);
155 if (ret < 0)
156 goto err;
157 }
158
159 platform_set_drvdata(pdev, leds_data);
160
161 return 0;
162
163err:
164 for (i = i - 1; i >= 0; i--)
165 delete_gpio_led(&leds_data[i]);
166
167 kfree(leds_data);
168
169 return ret;
170}
171
172static int __devexit gpio_led_remove(struct platform_device *pdev)
173{
174 int i;
175 struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
176 struct gpio_led_data *leds_data;
177
178 leds_data = platform_get_drvdata(pdev);
179
180 for (i = 0; i < pdata->num_leds; i++)
181 delete_gpio_led(&leds_data[i]);
182
183 kfree(leds_data);
184
185 return 0;
186}
187
188static struct platform_driver gpio_led_driver = {
189 .probe = gpio_led_probe,
190 .remove = __devexit_p(gpio_led_remove),
191 .driver = {
192 .name = "leds-gpio",
193 .owner = THIS_MODULE,
194 },
195};
196
197MODULE_ALIAS("platform:leds-gpio");
198#endif
199
200
201#ifdef CONFIG_LEDS_GPIO_OF
202#include <linux/of_platform.h>
203#include <linux/of_gpio.h>
204
205struct gpio_led_of_platform_data {
206 int num_leds;
207 struct gpio_led_data led_data[];
208};
209
210static int __devinit of_gpio_leds_probe(struct of_device *ofdev,
211 const struct of_device_id *match)
212{
213 struct device_node *np = ofdev->node, *child;
214 struct gpio_led led;
215 struct gpio_led_of_platform_data *pdata;
216 int count = 0, ret;
217
218
219 for_each_child_of_node(np, child)
220 count++;
221 if (!count)
222 return 0;
223
224 pdata = kzalloc(sizeof(*pdata) + sizeof(struct gpio_led_data) * count,
225 GFP_KERNEL);
226 if (!pdata)
227 return -ENOMEM;
228
229 memset(&led, 0, sizeof(led));
230 for_each_child_of_node(np, child) {
231 enum of_gpio_flags flags;
232 const char *state;
233
234 led.gpio = of_get_gpio_flags(child, 0, &flags);
235 led.active_low = flags & OF_GPIO_ACTIVE_LOW;
236 led.name = of_get_property(child, "label", NULL) ? : child->name;
237 led.default_trigger =
238 of_get_property(child, "linux,default-trigger", NULL);
239 state = of_get_property(child, "default-state", NULL);
240 if (state) {
241 if (!strcmp(state, "keep"))
242 led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
243 else if(!strcmp(state, "on"))
244 led.default_state = LEDS_GPIO_DEFSTATE_ON;
245 else
246 led.default_state = LEDS_GPIO_DEFSTATE_OFF;
247 }
248
249 ret = create_gpio_led(&led, &pdata->led_data[pdata->num_leds++],
250 &ofdev->dev, NULL);
251 if (ret < 0) {
252 of_node_put(child);
253 goto err;
254 }
255 }
256
257 dev_set_drvdata(&ofdev->dev, pdata);
258
259 return 0;
260
261err:
262 for (count = pdata->num_leds - 2; count >= 0; count--)
263 delete_gpio_led(&pdata->led_data[count]);
264
265 kfree(pdata);
266
267 return ret;
268}
269
270static int __devexit of_gpio_leds_remove(struct of_device *ofdev)
271{
272 struct gpio_led_of_platform_data *pdata = dev_get_drvdata(&ofdev->dev);
273 int i;
274
275 for (i = 0; i < pdata->num_leds; i++)
276 delete_gpio_led(&pdata->led_data[i]);
277
278 kfree(pdata);
279
280 dev_set_drvdata(&ofdev->dev, NULL);
281
282 return 0;
283}
284
285static const struct of_device_id of_gpio_leds_match[] = {
286 { .compatible = "gpio-leds", },
287 {},
288};
289
290static struct of_platform_driver of_gpio_leds_driver = {
291 .driver = {
292 .name = "of_gpio_leds",
293 .owner = THIS_MODULE,
294 },
295 .match_table = of_gpio_leds_match,
296 .probe = of_gpio_leds_probe,
297 .remove = __devexit_p(of_gpio_leds_remove),
298};
299#endif
300
301static int __init gpio_led_init(void)
302{
303 int ret;
304
305#ifdef CONFIG_LEDS_GPIO_PLATFORM
306 ret = platform_driver_register(&gpio_led_driver);
307 if (ret)
308 return ret;
309#endif
310#ifdef CONFIG_LEDS_GPIO_OF
311 ret = of_register_platform_driver(&of_gpio_leds_driver);
312#endif
313#ifdef CONFIG_LEDS_GPIO_PLATFORM
314 if (ret)
315 platform_driver_unregister(&gpio_led_driver);
316#endif
317
318 return ret;
319}
320
321static void __exit gpio_led_exit(void)
322{
323#ifdef CONFIG_LEDS_GPIO_PLATFORM
324 platform_driver_unregister(&gpio_led_driver);
325#endif
326#ifdef CONFIG_LEDS_GPIO_OF
327 of_unregister_platform_driver(&of_gpio_leds_driver);
328#endif
329}
330
331module_init(gpio_led_init);
332module_exit(gpio_led_exit);
333
334MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
335MODULE_DESCRIPTION("GPIO LED driver");
336MODULE_LICENSE("GPL");
337
