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Raphael Assenat22e03f32007-02-27 19:49:53 +00001/*
2 * LEDs driver for GPIOs
3 *
4 * Copyright (C) 2007 8D Technologies inc.
5 * Raphael Assenat <raph@8d.com>
Trent Piephoa7d878a2009-01-10 17:26:01 +00006 * Copyright (C) 2008 Freescale Semiconductor, Inc.
Raphael Assenat22e03f32007-02-27 19:49:53 +00007 *
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/kernel.h>
14#include <linux/init.h>
15#include <linux/platform_device.h>
16#include <linux/leds.h>
Grant Likelya314c5c2011-02-22 20:06:04 -070017#include <linux/of_platform.h>
18#include <linux/of_gpio.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090019#include <linux/slab.h>
David Brownell00852272007-05-10 10:51:41 +010020#include <linux/workqueue.h>
Paul Gortmaker54f4ded2011-07-03 13:56:03 -040021#include <linux/module.h>
David Brownell00852272007-05-10 10:51:41 +010022
Raphael Assenat22e03f32007-02-27 19:49:53 +000023#include <asm/gpio.h>
24
25struct gpio_led_data {
26 struct led_classdev cdev;
27 unsigned gpio;
David Brownell00852272007-05-10 10:51:41 +010028 struct work_struct work;
29 u8 new_level;
30 u8 can_sleep;
Raphael Assenat22e03f32007-02-27 19:49:53 +000031 u8 active_low;
Benjamin Herrenschmidt21463252010-05-22 20:54:55 +100032 u8 blinking;
33 int (*platform_gpio_blink_set)(unsigned gpio, int state,
Herbert Valerio Riedelca3259b2008-03-09 23:48:25 +000034 unsigned long *delay_on, unsigned long *delay_off);
Raphael Assenat22e03f32007-02-27 19:49:53 +000035};
36
David Brownell00852272007-05-10 10:51:41 +010037static void gpio_led_work(struct work_struct *work)
38{
39 struct gpio_led_data *led_dat =
40 container_of(work, struct gpio_led_data, work);
41
Benjamin Herrenschmidt21463252010-05-22 20:54:55 +100042 if (led_dat->blinking) {
43 led_dat->platform_gpio_blink_set(led_dat->gpio,
44 led_dat->new_level,
45 NULL, NULL);
46 led_dat->blinking = 0;
47 } else
48 gpio_set_value_cansleep(led_dat->gpio, led_dat->new_level);
David Brownell00852272007-05-10 10:51:41 +010049}
Raphael Assenat22e03f32007-02-27 19:49:53 +000050
51static void gpio_led_set(struct led_classdev *led_cdev,
52 enum led_brightness value)
53{
54 struct gpio_led_data *led_dat =
55 container_of(led_cdev, struct gpio_led_data, cdev);
56 int level;
57
58 if (value == LED_OFF)
59 level = 0;
60 else
61 level = 1;
62
63 if (led_dat->active_low)
64 level = !level;
65
David Brownell306dd852008-03-27 00:59:02 +000066 /* Setting GPIOs with I2C/etc requires a task context, and we don't
67 * seem to have a reliable way to know if we're already in one; so
68 * let's just assume the worst.
69 */
David Brownell00852272007-05-10 10:51:41 +010070 if (led_dat->can_sleep) {
David Brownell306dd852008-03-27 00:59:02 +000071 led_dat->new_level = level;
72 schedule_work(&led_dat->work);
Benjamin Herrenschmidt21463252010-05-22 20:54:55 +100073 } else {
74 if (led_dat->blinking) {
75 led_dat->platform_gpio_blink_set(led_dat->gpio, level,
76 NULL, NULL);
77 led_dat->blinking = 0;
78 } else
79 gpio_set_value(led_dat->gpio, level);
80 }
Raphael Assenat22e03f32007-02-27 19:49:53 +000081}
82
Herbert Valerio Riedelca3259b2008-03-09 23:48:25 +000083static int gpio_blink_set(struct led_classdev *led_cdev,
84 unsigned long *delay_on, unsigned long *delay_off)
85{
86 struct gpio_led_data *led_dat =
87 container_of(led_cdev, struct gpio_led_data, cdev);
88
Benjamin Herrenschmidt21463252010-05-22 20:54:55 +100089 led_dat->blinking = 1;
90 return led_dat->platform_gpio_blink_set(led_dat->gpio, GPIO_LED_BLINK,
91 delay_on, delay_off);
Herbert Valerio Riedelca3259b2008-03-09 23:48:25 +000092}
93
Trent Piephoa7d878a2009-01-10 17:26:01 +000094static int __devinit create_gpio_led(const struct gpio_led *template,
95 struct gpio_led_data *led_dat, struct device *parent,
Benjamin Herrenschmidt21463252010-05-22 20:54:55 +100096 int (*blink_set)(unsigned, int, unsigned long *, unsigned long *))
Trent Piephoa7d878a2009-01-10 17:26:01 +000097{
Trent Piephoed88bae2009-05-12 15:33:12 -070098 int ret, state;
Trent Piephoa7d878a2009-01-10 17:26:01 +000099
Dmitry Eremin-Solenikov0b4634f2009-11-16 01:48:32 +0300100 led_dat->gpio = -1;
101
David Brownelld379ee82009-03-05 16:46:44 -0800102 /* skip leds that aren't available */
103 if (!gpio_is_valid(template->gpio)) {
Michal Simek2fea0922009-08-06 16:04:51 -0700104 printk(KERN_INFO "Skipping unavailable LED gpio %d (%s)\n",
David Brownelld379ee82009-03-05 16:46:44 -0800105 template->gpio, template->name);
David Brownellac15e952009-04-07 17:51:49 -0700106 return 0;
David Brownelld379ee82009-03-05 16:46:44 -0800107 }
108
Trent Piephoa7d878a2009-01-10 17:26:01 +0000109 ret = gpio_request(template->gpio, template->name);
110 if (ret < 0)
111 return ret;
112
113 led_dat->cdev.name = template->name;
114 led_dat->cdev.default_trigger = template->default_trigger;
115 led_dat->gpio = template->gpio;
116 led_dat->can_sleep = gpio_cansleep(template->gpio);
117 led_dat->active_low = template->active_low;
Benjamin Herrenschmidt21463252010-05-22 20:54:55 +1000118 led_dat->blinking = 0;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000119 if (blink_set) {
120 led_dat->platform_gpio_blink_set = blink_set;
121 led_dat->cdev.blink_set = gpio_blink_set;
122 }
123 led_dat->cdev.brightness_set = gpio_led_set;
Trent Piephoed88bae2009-05-12 15:33:12 -0700124 if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP)
David Daneydabc69c2011-10-31 17:12:17 -0700125 state = !!gpio_get_value_cansleep(led_dat->gpio) ^ led_dat->active_low;
Trent Piephoed88bae2009-05-12 15:33:12 -0700126 else
127 state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
128 led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
Richard Purdiedefb5122009-02-17 15:04:07 +0000129 if (!template->retain_state_suspended)
130 led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000131
Trent Piephoed88bae2009-05-12 15:33:12 -0700132 ret = gpio_direction_output(led_dat->gpio, led_dat->active_low ^ state);
Trent Piephoa7d878a2009-01-10 17:26:01 +0000133 if (ret < 0)
134 goto err;
Benjamin Herrenschmidt21463252010-05-22 20:54:55 +1000135
Trent Piephoa7d878a2009-01-10 17:26:01 +0000136 INIT_WORK(&led_dat->work, gpio_led_work);
137
138 ret = led_classdev_register(parent, &led_dat->cdev);
139 if (ret < 0)
140 goto err;
141
142 return 0;
143err:
144 gpio_free(led_dat->gpio);
145 return ret;
146}
147
148static void delete_gpio_led(struct gpio_led_data *led)
149{
David Brownelld379ee82009-03-05 16:46:44 -0800150 if (!gpio_is_valid(led->gpio))
151 return;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000152 led_classdev_unregister(&led->cdev);
153 cancel_work_sync(&led->work);
154 gpio_free(led->gpio);
155}
156
Grant Likelya314c5c2011-02-22 20:06:04 -0700157struct gpio_leds_priv {
158 int num_leds;
159 struct gpio_led_data leds[];
Raphael Assenat22e03f32007-02-27 19:49:53 +0000160};
161
Grant Likelya314c5c2011-02-22 20:06:04 -0700162static inline int sizeof_gpio_leds_priv(int num_leds)
163{
164 return sizeof(struct gpio_leds_priv) +
165 (sizeof(struct gpio_led_data) * num_leds);
166}
Trent Piephoa7d878a2009-01-10 17:26:01 +0000167
168/* Code to create from OpenFirmware platform devices */
Shawn Guo2bcc7ed2011-05-31 16:23:43 +0800169#ifdef CONFIG_OF_GPIO
Grant Likelya314c5c2011-02-22 20:06:04 -0700170static struct gpio_leds_priv * __devinit gpio_leds_create_of(struct platform_device *pdev)
Trent Piephoa7d878a2009-01-10 17:26:01 +0000171{
Grant Likelya314c5c2011-02-22 20:06:04 -0700172 struct device_node *np = pdev->dev.of_node, *child;
173 struct gpio_leds_priv *priv;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000174 int count = 0, ret;
175
Grant Likelya314c5c2011-02-22 20:06:04 -0700176 /* count LEDs in this device, so we know how much to allocate */
Trent Piephoa7d878a2009-01-10 17:26:01 +0000177 for_each_child_of_node(np, child)
178 count++;
179 if (!count)
Grant Likelya314c5c2011-02-22 20:06:04 -0700180 return NULL;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000181
Grant Likelya314c5c2011-02-22 20:06:04 -0700182 priv = kzalloc(sizeof_gpio_leds_priv(count), GFP_KERNEL);
183 if (!priv)
184 return NULL;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000185
Trent Piephoa7d878a2009-01-10 17:26:01 +0000186 for_each_child_of_node(np, child) {
Anton Vorontsov0493a4f2010-03-11 13:58:47 -0800187 struct gpio_led led = {};
Trent Piephoa7d878a2009-01-10 17:26:01 +0000188 enum of_gpio_flags flags;
Trent Piephoed88bae2009-05-12 15:33:12 -0700189 const char *state;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000190
191 led.gpio = of_get_gpio_flags(child, 0, &flags);
192 led.active_low = flags & OF_GPIO_ACTIVE_LOW;
193 led.name = of_get_property(child, "label", NULL) ? : child->name;
194 led.default_trigger =
195 of_get_property(child, "linux,default-trigger", NULL);
Trent Piephoed88bae2009-05-12 15:33:12 -0700196 state = of_get_property(child, "default-state", NULL);
197 if (state) {
198 if (!strcmp(state, "keep"))
199 led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
Grant Likelya314c5c2011-02-22 20:06:04 -0700200 else if (!strcmp(state, "on"))
Trent Piephoed88bae2009-05-12 15:33:12 -0700201 led.default_state = LEDS_GPIO_DEFSTATE_ON;
202 else
203 led.default_state = LEDS_GPIO_DEFSTATE_OFF;
204 }
Trent Piephoa7d878a2009-01-10 17:26:01 +0000205
Grant Likelya314c5c2011-02-22 20:06:04 -0700206 ret = create_gpio_led(&led, &priv->leds[priv->num_leds++],
207 &pdev->dev, NULL);
Trent Piephoa7d878a2009-01-10 17:26:01 +0000208 if (ret < 0) {
209 of_node_put(child);
210 goto err;
211 }
212 }
213
Grant Likelya314c5c2011-02-22 20:06:04 -0700214 return priv;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000215
216err:
Grant Likelya314c5c2011-02-22 20:06:04 -0700217 for (count = priv->num_leds - 2; count >= 0; count--)
218 delete_gpio_led(&priv->leds[count]);
219 kfree(priv);
220 return NULL;
Trent Piephoa7d878a2009-01-10 17:26:01 +0000221}
222
223static const struct of_device_id of_gpio_leds_match[] = {
224 { .compatible = "gpio-leds", },
225 {},
226};
Shawn Guo2bcc7ed2011-05-31 16:23:43 +0800227#else /* CONFIG_OF_GPIO */
Grant Likelya314c5c2011-02-22 20:06:04 -0700228static struct gpio_leds_priv * __devinit gpio_leds_create_of(struct platform_device *pdev)
229{
230 return NULL;
231}
232#define of_gpio_leds_match NULL
Shawn Guo2bcc7ed2011-05-31 16:23:43 +0800233#endif /* CONFIG_OF_GPIO */
Trent Piephoa7d878a2009-01-10 17:26:01 +0000234
Grant Likelya314c5c2011-02-22 20:06:04 -0700235
236static int __devinit gpio_led_probe(struct platform_device *pdev)
237{
238 struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
239 struct gpio_leds_priv *priv;
240 int i, ret = 0;
241
242 if (pdata && pdata->num_leds) {
243 priv = kzalloc(sizeof_gpio_leds_priv(pdata->num_leds),
244 GFP_KERNEL);
245 if (!priv)
246 return -ENOMEM;
247
248 priv->num_leds = pdata->num_leds;
249 for (i = 0; i < priv->num_leds; i++) {
250 ret = create_gpio_led(&pdata->leds[i],
251 &priv->leds[i],
252 &pdev->dev, pdata->gpio_blink_set);
253 if (ret < 0) {
254 /* On failure: unwind the led creations */
255 for (i = i - 1; i >= 0; i--)
256 delete_gpio_led(&priv->leds[i]);
257 kfree(priv);
258 return ret;
259 }
260 }
261 } else {
262 priv = gpio_leds_create_of(pdev);
263 if (!priv)
264 return -ENODEV;
265 }
266
267 platform_set_drvdata(pdev, priv);
268
269 return 0;
270}
271
272static int __devexit gpio_led_remove(struct platform_device *pdev)
273{
274 struct gpio_leds_priv *priv = dev_get_drvdata(&pdev->dev);
275 int i;
276
277 for (i = 0; i < priv->num_leds; i++)
278 delete_gpio_led(&priv->leds[i]);
279
280 dev_set_drvdata(&pdev->dev, NULL);
281 kfree(priv);
282
283 return 0;
284}
285
286static struct platform_driver gpio_led_driver = {
287 .probe = gpio_led_probe,
288 .remove = __devexit_p(gpio_led_remove),
289 .driver = {
290 .name = "leds-gpio",
291 .owner = THIS_MODULE,
Grant Likely40182942010-04-13 16:13:02 -0700292 .of_match_table = of_gpio_leds_match,
Trent Piephoa7d878a2009-01-10 17:26:01 +0000293 },
Trent Piephoa7d878a2009-01-10 17:26:01 +0000294};
Grant Likelya314c5c2011-02-22 20:06:04 -0700295
296MODULE_ALIAS("platform:leds-gpio");
Trent Piephoa7d878a2009-01-10 17:26:01 +0000297
Richard Purdieb2bdc3e2009-02-02 23:04:42 +0000298static int __init gpio_led_init(void)
299{
Grant Likelya314c5c2011-02-22 20:06:04 -0700300 return platform_driver_register(&gpio_led_driver);
Richard Purdieb2bdc3e2009-02-02 23:04:42 +0000301}
302
303static void __exit gpio_led_exit(void)
304{
Richard Purdieb2bdc3e2009-02-02 23:04:42 +0000305 platform_driver_unregister(&gpio_led_driver);
Richard Purdieb2bdc3e2009-02-02 23:04:42 +0000306}
307
308module_init(gpio_led_init);
309module_exit(gpio_led_exit);
310
Trent Piephoa7d878a2009-01-10 17:26:01 +0000311MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
Raphael Assenat22e03f32007-02-27 19:49:53 +0000312MODULE_DESCRIPTION("GPIO LED driver");
313MODULE_LICENSE("GPL");