blob: 4a1276578352283544ceb6fda2ff176d0772d887 [file] [log] [blame]
Mark Brown0081e802008-12-04 16:52:33 +00001/*
2 * LED driver for WM8350 driven LEDS.
3 *
4 * Copyright(C) 2007, 2008 Wolfson Microelectronics PLC.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 */
11
12#include <linux/kernel.h>
13#include <linux/init.h>
14#include <linux/platform_device.h>
15#include <linux/leds.h>
16#include <linux/err.h>
17#include <linux/mfd/wm8350/pmic.h>
18#include <linux/regulator/consumer.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090019#include <linux/slab.h>
Paul Gortmaker54f4ded2011-07-03 13:56:03 -040020#include <linux/module.h>
Mark Brown0081e802008-12-04 16:52:33 +000021
22/* Microamps */
23static const int isink_cur[] = {
24 4,
25 5,
26 6,
27 7,
28 8,
29 10,
30 11,
31 14,
32 16,
33 19,
34 23,
35 27,
36 32,
37 39,
38 46,
39 54,
40 65,
41 77,
42 92,
43 109,
44 130,
45 154,
46 183,
47 218,
48 259,
49 308,
50 367,
51 436,
52 518,
53 616,
54 733,
55 872,
56 1037,
57 1233,
58 1466,
59 1744,
60 2073,
61 2466,
62 2933,
63 3487,
64 4147,
65 4932,
66 5865,
67 6975,
68 8294,
69 9864,
70 11730,
71 13949,
72 16589,
73 19728,
74 23460,
75 27899,
76 33178,
77 39455,
78 46920,
79 55798,
80 66355,
81 78910,
82 93840,
83 111596,
84 132710,
85 157820,
86 187681,
87 223191
88};
89
90#define to_wm8350_led(led_cdev) \
91 container_of(led_cdev, struct wm8350_led, cdev)
92
93static void wm8350_led_enable(struct wm8350_led *led)
94{
95 int ret;
96
97 if (led->enabled)
98 return;
99
100 ret = regulator_enable(led->isink);
101 if (ret != 0) {
102 dev_err(led->cdev.dev, "Failed to enable ISINK: %d\n", ret);
103 return;
104 }
105
106 ret = regulator_enable(led->dcdc);
107 if (ret != 0) {
108 dev_err(led->cdev.dev, "Failed to enable DCDC: %d\n", ret);
109 regulator_disable(led->isink);
110 return;
111 }
112
113 led->enabled = 1;
114}
115
116static void wm8350_led_disable(struct wm8350_led *led)
117{
118 int ret;
119
120 if (!led->enabled)
121 return;
122
123 ret = regulator_disable(led->dcdc);
124 if (ret != 0) {
125 dev_err(led->cdev.dev, "Failed to disable DCDC: %d\n", ret);
126 return;
127 }
128
129 ret = regulator_disable(led->isink);
130 if (ret != 0) {
131 dev_err(led->cdev.dev, "Failed to disable ISINK: %d\n", ret);
132 regulator_enable(led->dcdc);
133 return;
134 }
135
136 led->enabled = 0;
137}
138
139static void led_work(struct work_struct *work)
140{
141 struct wm8350_led *led = container_of(work, struct wm8350_led, work);
142 int ret;
143 int uA;
144 unsigned long flags;
145
146 mutex_lock(&led->mutex);
147
148 spin_lock_irqsave(&led->value_lock, flags);
149
150 if (led->value == LED_OFF) {
151 spin_unlock_irqrestore(&led->value_lock, flags);
152 wm8350_led_disable(led);
153 goto out;
154 }
155
156 /* This scales linearly into the index of valid current
157 * settings which results in a linear scaling of perceived
158 * brightness due to the non-linear current settings provided
159 * by the hardware.
160 */
161 uA = (led->max_uA_index * led->value) / LED_FULL;
162 spin_unlock_irqrestore(&led->value_lock, flags);
163 BUG_ON(uA >= ARRAY_SIZE(isink_cur));
164
165 ret = regulator_set_current_limit(led->isink, isink_cur[uA],
166 isink_cur[uA]);
167 if (ret != 0)
168 dev_err(led->cdev.dev, "Failed to set %duA: %d\n",
169 isink_cur[uA], ret);
170
171 wm8350_led_enable(led);
172
173out:
174 mutex_unlock(&led->mutex);
175}
176
177static void wm8350_led_set(struct led_classdev *led_cdev,
178 enum led_brightness value)
179{
180 struct wm8350_led *led = to_wm8350_led(led_cdev);
181 unsigned long flags;
182
183 spin_lock_irqsave(&led->value_lock, flags);
184 led->value = value;
185 schedule_work(&led->work);
186 spin_unlock_irqrestore(&led->value_lock, flags);
187}
188
Mark Brown0081e802008-12-04 16:52:33 +0000189static void wm8350_led_shutdown(struct platform_device *pdev)
190{
191 struct wm8350_led *led = platform_get_drvdata(pdev);
192
193 mutex_lock(&led->mutex);
194 led->value = LED_OFF;
195 wm8350_led_disable(led);
196 mutex_unlock(&led->mutex);
197}
198
199static int wm8350_led_probe(struct platform_device *pdev)
200{
201 struct regulator *isink, *dcdc;
202 struct wm8350_led *led;
203 struct wm8350_led_platform_data *pdata = pdev->dev.platform_data;
204 int ret, i;
205
206 if (pdata == NULL) {
207 dev_err(&pdev->dev, "no platform data\n");
208 return -ENODEV;
209 }
210
211 if (pdata->max_uA < isink_cur[0]) {
212 dev_err(&pdev->dev, "Invalid maximum current %duA\n",
213 pdata->max_uA);
214 return -EINVAL;
215 }
216
217 isink = regulator_get(&pdev->dev, "led_isink");
218 if (IS_ERR(isink)) {
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300219 printk(KERN_ERR "%s: can't get ISINK\n", __func__);
Mark Brown0081e802008-12-04 16:52:33 +0000220 return PTR_ERR(isink);
221 }
222
223 dcdc = regulator_get(&pdev->dev, "led_vcc");
224 if (IS_ERR(dcdc)) {
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300225 printk(KERN_ERR "%s: can't get DCDC\n", __func__);
Mark Brown0081e802008-12-04 16:52:33 +0000226 ret = PTR_ERR(dcdc);
227 goto err_isink;
228 }
229
230 led = kzalloc(sizeof(*led), GFP_KERNEL);
231 if (led == NULL) {
232 ret = -ENOMEM;
233 goto err_dcdc;
234 }
235
236 led->cdev.brightness_set = wm8350_led_set;
237 led->cdev.default_trigger = pdata->default_trigger;
238 led->cdev.name = pdata->name;
Richard Purdie859cb7f2009-01-08 17:55:03 +0000239 led->cdev.flags |= LED_CORE_SUSPENDRESUME;
Mark Brown0081e802008-12-04 16:52:33 +0000240 led->enabled = regulator_is_enabled(isink);
241 led->isink = isink;
242 led->dcdc = dcdc;
243
244 for (i = 0; i < ARRAY_SIZE(isink_cur) - 1; i++)
245 if (isink_cur[i] >= pdata->max_uA)
246 break;
247 led->max_uA_index = i;
248 if (pdata->max_uA != isink_cur[i])
249 dev_warn(&pdev->dev,
250 "Maximum current %duA is not directly supported,"
251 " check platform data\n",
252 pdata->max_uA);
253
254 spin_lock_init(&led->value_lock);
255 mutex_init(&led->mutex);
256 INIT_WORK(&led->work, led_work);
257 led->value = LED_OFF;
258 platform_set_drvdata(pdev, led);
259
260 ret = led_classdev_register(&pdev->dev, &led->cdev);
261 if (ret < 0)
262 goto err_led;
263
264 return 0;
265
266 err_led:
267 kfree(led);
268 err_dcdc:
269 regulator_put(dcdc);
270 err_isink:
271 regulator_put(isink);
272 return ret;
273}
274
275static int wm8350_led_remove(struct platform_device *pdev)
276{
277 struct wm8350_led *led = platform_get_drvdata(pdev);
278
279 led_classdev_unregister(&led->cdev);
Tejun Heo99ef2122010-12-24 15:59:07 +0100280 flush_work_sync(&led->work);
Mark Brown0081e802008-12-04 16:52:33 +0000281 wm8350_led_disable(led);
282 regulator_put(led->dcdc);
283 regulator_put(led->isink);
284 kfree(led);
285 return 0;
286}
287
288static struct platform_driver wm8350_led_driver = {
289 .driver = {
290 .name = "wm8350-led",
291 .owner = THIS_MODULE,
292 },
293 .probe = wm8350_led_probe,
294 .remove = wm8350_led_remove,
295 .shutdown = wm8350_led_shutdown,
Mark Brown0081e802008-12-04 16:52:33 +0000296};
297
298static int __devinit wm8350_led_init(void)
299{
300 return platform_driver_register(&wm8350_led_driver);
301}
302module_init(wm8350_led_init);
303
304static void wm8350_led_exit(void)
305{
306 platform_driver_unregister(&wm8350_led_driver);
307}
308module_exit(wm8350_led_exit);
309
310MODULE_AUTHOR("Mark Brown");
311MODULE_DESCRIPTION("WM8350 LED driver");
312MODULE_LICENSE("GPL");
313MODULE_ALIAS("platform:wm8350-led");