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PM / sleep: Asynchronous threads for suspend_noirq
[linux/fpc-iii.git] / drivers / leds / leds-lm3530.c
blob652368c2ea9a5b9ca1d806de4057747a2c2fea0a
1 /*
2 * Copyright (C) 2011 ST-Ericsson SA.
3 * Copyright (C) 2009 Motorola, Inc.
4 *
5 * License Terms: GNU General Public License v2
6 *
7 * Simple driver for National Semiconductor LM3530 Backlight driver chip
8 *
9 * Author: Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>
10 * based on leds-lm3530.c by Dan Murphy <D.Murphy@motorola.com>
11 */
12
13 #include <linux/i2c.h>
14 #include <linux/leds.h>
15 #include <linux/slab.h>
16 #include <linux/platform_device.h>
17 #include <linux/input.h>
18 #include <linux/led-lm3530.h>
19 #include <linux/types.h>
20 #include <linux/regulator/consumer.h>
21 #include <linux/module.h>
22
23 #define LM3530_LED_DEV "lcd-backlight"
24 #define LM3530_NAME "lm3530-led"
25
26 #define LM3530_GEN_CONFIG 0x10
27 #define LM3530_ALS_CONFIG 0x20
28 #define LM3530_BRT_RAMP_RATE 0x30
29 #define LM3530_ALS_IMP_SELECT 0x41
30 #define LM3530_BRT_CTRL_REG 0xA0
31 #define LM3530_ALS_ZB0_REG 0x60
32 #define LM3530_ALS_ZB1_REG 0x61
33 #define LM3530_ALS_ZB2_REG 0x62
34 #define LM3530_ALS_ZB3_REG 0x63
35 #define LM3530_ALS_Z0T_REG 0x70
36 #define LM3530_ALS_Z1T_REG 0x71
37 #define LM3530_ALS_Z2T_REG 0x72
38 #define LM3530_ALS_Z3T_REG 0x73
39 #define LM3530_ALS_Z4T_REG 0x74
40 #define LM3530_REG_MAX 14
41
42 /* General Control Register */
43 #define LM3530_EN_I2C_SHIFT (0)
44 #define LM3530_RAMP_LAW_SHIFT (1)
45 #define LM3530_MAX_CURR_SHIFT (2)
46 #define LM3530_EN_PWM_SHIFT (5)
47 #define LM3530_PWM_POL_SHIFT (6)
48 #define LM3530_EN_PWM_SIMPLE_SHIFT (7)
49
50 #define LM3530_ENABLE_I2C (1 << LM3530_EN_I2C_SHIFT)
51 #define LM3530_ENABLE_PWM (1 << LM3530_EN_PWM_SHIFT)
52 #define LM3530_POL_LOW (1 << LM3530_PWM_POL_SHIFT)
53 #define LM3530_ENABLE_PWM_SIMPLE (1 << LM3530_EN_PWM_SIMPLE_SHIFT)
54
55 /* ALS Config Register Options */
56 #define LM3530_ALS_AVG_TIME_SHIFT (0)
57 #define LM3530_EN_ALS_SHIFT (3)
58 #define LM3530_ALS_SEL_SHIFT (5)
59
60 #define LM3530_ENABLE_ALS (3 << LM3530_EN_ALS_SHIFT)
61
62 /* Brightness Ramp Rate Register */
63 #define LM3530_BRT_RAMP_FALL_SHIFT (0)
64 #define LM3530_BRT_RAMP_RISE_SHIFT (3)
65
66 /* ALS Resistor Select */
67 #define LM3530_ALS1_IMP_SHIFT (0)
68 #define LM3530_ALS2_IMP_SHIFT (4)
69
70 /* Zone Boundary Register defaults */
71 #define LM3530_ALS_ZB_MAX (4)
72 #define LM3530_ALS_WINDOW_mV (1000)
73 #define LM3530_ALS_OFFSET_mV (4)
74
75 /* Zone Target Register defaults */
76 #define LM3530_DEF_ZT_0 (0x7F)
77 #define LM3530_DEF_ZT_1 (0x66)
78 #define LM3530_DEF_ZT_2 (0x4C)
79 #define LM3530_DEF_ZT_3 (0x33)
80 #define LM3530_DEF_ZT_4 (0x19)
81
82 /* 7 bits are used for the brightness : LM3530_BRT_CTRL_REG */
83 #define MAX_BRIGHTNESS (127)
84
85 struct lm3530_mode_map {
86 const char *mode;
87 enum lm3530_mode mode_val;
88 };
89
90 static struct lm3530_mode_map mode_map[] = {
91 { "man", LM3530_BL_MODE_MANUAL },
92 { "als", LM3530_BL_MODE_ALS },
93 { "pwm", LM3530_BL_MODE_PWM },
94 };
95
96 /**
97 * struct lm3530_data
98 * @led_dev: led class device
99 * @client: i2c client
100 * @pdata: LM3530 platform data
101 * @mode: mode of operation - manual, ALS, PWM
102 * @regulator: regulator
103 * @brighness: previous brightness value
104 * @enable: regulator is enabled
105 */
106 struct lm3530_data {
107 struct led_classdev led_dev;
108 struct i2c_client *client;
109 struct lm3530_platform_data *pdata;
110 enum lm3530_mode mode;
111 struct regulator *regulator;
112 enum led_brightness brightness;
113 bool enable;
114 };
115
116 /*
117 * struct lm3530_als_data
118 * @config : value of ALS configuration register
119 * @imp_sel : value of ALS resistor select register
120 * @zone : values of ALS ZB(Zone Boundary) registers
121 */
122 struct lm3530_als_data {
123 u8 config;
124 u8 imp_sel;
125 u8 zones[LM3530_ALS_ZB_MAX];
126 };
127
128 static const u8 lm3530_reg[LM3530_REG_MAX] = {
129 LM3530_GEN_CONFIG,
130 LM3530_ALS_CONFIG,
131 LM3530_BRT_RAMP_RATE,
132 LM3530_ALS_IMP_SELECT,
133 LM3530_BRT_CTRL_REG,
134 LM3530_ALS_ZB0_REG,
135 LM3530_ALS_ZB1_REG,
136 LM3530_ALS_ZB2_REG,
137 LM3530_ALS_ZB3_REG,
138 LM3530_ALS_Z0T_REG,
139 LM3530_ALS_Z1T_REG,
140 LM3530_ALS_Z2T_REG,
141 LM3530_ALS_Z3T_REG,
142 LM3530_ALS_Z4T_REG,
143 };
144
145 static int lm3530_get_mode_from_str(const char *str)
146 {
147 int i;
148
149 for (i = 0; i < ARRAY_SIZE(mode_map); i++)
150 if (sysfs_streq(str, mode_map[i].mode))
151 return mode_map[i].mode_val;
152
153 return -EINVAL;
154 }
155
156 static void lm3530_als_configure(struct lm3530_platform_data *pdata,
157 struct lm3530_als_data *als)
158 {
159 int i;
160 u32 als_vmin, als_vmax, als_vstep;
161
162 if (pdata->als_vmax == 0) {
163 pdata->als_vmin = 0;
164 pdata->als_vmax = LM3530_ALS_WINDOW_mV;
165 }
166
167 als_vmin = pdata->als_vmin;
168 als_vmax = pdata->als_vmax;
169
170 if ((als_vmax - als_vmin) > LM3530_ALS_WINDOW_mV)
171 pdata->als_vmax = als_vmax = als_vmin + LM3530_ALS_WINDOW_mV;
172
173 /* n zone boundary makes n+1 zones */
174 als_vstep = (als_vmax - als_vmin) / (LM3530_ALS_ZB_MAX + 1);
175
176 for (i = 0; i < LM3530_ALS_ZB_MAX; i++)
177 als->zones[i] = (((als_vmin + LM3530_ALS_OFFSET_mV) +
178 als_vstep + (i * als_vstep)) * LED_FULL) / 1000;
179
180 als->config =
181 (pdata->als_avrg_time << LM3530_ALS_AVG_TIME_SHIFT) |
182 (LM3530_ENABLE_ALS) |
183 (pdata->als_input_mode << LM3530_ALS_SEL_SHIFT);
184
185 als->imp_sel =
186 (pdata->als1_resistor_sel << LM3530_ALS1_IMP_SHIFT) |
187 (pdata->als2_resistor_sel << LM3530_ALS2_IMP_SHIFT);
188 }
189
190 static int lm3530_led_enable(struct lm3530_data *drvdata)
191 {
192 int ret;
193
194 if (drvdata->enable)
195 return 0;
196
197 ret = regulator_enable(drvdata->regulator);
198 if (ret) {
199 dev_err(drvdata->led_dev.dev, "Failed to enable vin:%d\n", ret);
200 return ret;
201 }
202
203 drvdata->enable = true;
204 return 0;
205 }
206
207 static void lm3530_led_disable(struct lm3530_data *drvdata)
208 {
209 int ret;
210
211 if (!drvdata->enable)
212 return;
213
214 ret = regulator_disable(drvdata->regulator);
215 if (ret) {
216 dev_err(drvdata->led_dev.dev, "Failed to disable vin:%d\n",
217 ret);
218 return;
219 }
220
221 drvdata->enable = false;
222 }
223
224 static int lm3530_init_registers(struct lm3530_data *drvdata)
225 {
226 int ret = 0;
227 int i;
228 u8 gen_config;
229 u8 brt_ramp;
230 u8 brightness;
231 u8 reg_val[LM3530_REG_MAX];
232 struct lm3530_platform_data *pdata = drvdata->pdata;
233 struct i2c_client *client = drvdata->client;
234 struct lm3530_pwm_data *pwm = &pdata->pwm_data;
235 struct lm3530_als_data als;
236
237 memset(&als, 0, sizeof(struct lm3530_als_data));
238
239 gen_config = (pdata->brt_ramp_law << LM3530_RAMP_LAW_SHIFT) |
240 ((pdata->max_current & 7) << LM3530_MAX_CURR_SHIFT);
241
242 switch (drvdata->mode) {
243 case LM3530_BL_MODE_MANUAL:
244 gen_config |= LM3530_ENABLE_I2C;
245 break;
246 case LM3530_BL_MODE_ALS:
247 gen_config |= LM3530_ENABLE_I2C;
248 lm3530_als_configure(pdata, &als);
249 break;
250 case LM3530_BL_MODE_PWM:
251 gen_config |= LM3530_ENABLE_PWM | LM3530_ENABLE_PWM_SIMPLE |
252 (pdata->pwm_pol_hi << LM3530_PWM_POL_SHIFT);
253 break;
254 }
255
256 brt_ramp = (pdata->brt_ramp_fall << LM3530_BRT_RAMP_FALL_SHIFT) |
257 (pdata->brt_ramp_rise << LM3530_BRT_RAMP_RISE_SHIFT);
258
259 if (drvdata->brightness)
260 brightness = drvdata->brightness;
261 else
262 brightness = drvdata->brightness = pdata->brt_val;
263
264 if (brightness > drvdata->led_dev.max_brightness)
265 brightness = drvdata->led_dev.max_brightness;
266
267 reg_val[0] = gen_config; /* LM3530_GEN_CONFIG */
268 reg_val[1] = als.config; /* LM3530_ALS_CONFIG */
269 reg_val[2] = brt_ramp; /* LM3530_BRT_RAMP_RATE */
270 reg_val[3] = als.imp_sel; /* LM3530_ALS_IMP_SELECT */
271 reg_val[4] = brightness; /* LM3530_BRT_CTRL_REG */
272 reg_val[5] = als.zones[0]; /* LM3530_ALS_ZB0_REG */
273 reg_val[6] = als.zones[1]; /* LM3530_ALS_ZB1_REG */
274 reg_val[7] = als.zones[2]; /* LM3530_ALS_ZB2_REG */
275 reg_val[8] = als.zones[3]; /* LM3530_ALS_ZB3_REG */
276 reg_val[9] = LM3530_DEF_ZT_0; /* LM3530_ALS_Z0T_REG */
277 reg_val[10] = LM3530_DEF_ZT_1; /* LM3530_ALS_Z1T_REG */
278 reg_val[11] = LM3530_DEF_ZT_2; /* LM3530_ALS_Z2T_REG */
279 reg_val[12] = LM3530_DEF_ZT_3; /* LM3530_ALS_Z3T_REG */
280 reg_val[13] = LM3530_DEF_ZT_4; /* LM3530_ALS_Z4T_REG */
281
282 ret = lm3530_led_enable(drvdata);
283 if (ret)
284 return ret;
285
286 for (i = 0; i < LM3530_REG_MAX; i++) {
287 /* do not update brightness register when pwm mode */
288 if (lm3530_reg[i] == LM3530_BRT_CTRL_REG &&
289 drvdata->mode == LM3530_BL_MODE_PWM) {
290 if (pwm->pwm_set_intensity)
291 pwm->pwm_set_intensity(reg_val[i],
292 drvdata->led_dev.max_brightness);
293 continue;
294 }
295
296 ret = i2c_smbus_write_byte_data(client,
297 lm3530_reg[i], reg_val[i]);
298 if (ret)
299 break;
300 }
301
302 return ret;
303 }
304
305 static void lm3530_brightness_set(struct led_classdev *led_cdev,
306 enum led_brightness brt_val)
307 {
308 int err;
309 struct lm3530_data *drvdata =
310 container_of(led_cdev, struct lm3530_data, led_dev);
311 struct lm3530_platform_data *pdata = drvdata->pdata;
312 struct lm3530_pwm_data *pwm = &pdata->pwm_data;
313 u8 max_brightness = led_cdev->max_brightness;
314
315 switch (drvdata->mode) {
316 case LM3530_BL_MODE_MANUAL:
317
318 if (!drvdata->enable) {
319 err = lm3530_init_registers(drvdata);
320 if (err) {
321 dev_err(&drvdata->client->dev,
322 "Register Init failed: %d\n", err);
323 break;
324 }
325 }
326
327 /* set the brightness in brightness control register*/
328 err = i2c_smbus_write_byte_data(drvdata->client,
329 LM3530_BRT_CTRL_REG, brt_val);
330 if (err)
331 dev_err(&drvdata->client->dev,
332 "Unable to set brightness: %d\n", err);
333 else
334 drvdata->brightness = brt_val;
335
336 if (brt_val == 0)
337 lm3530_led_disable(drvdata);
338 break;
339 case LM3530_BL_MODE_ALS:
340 break;
341 case LM3530_BL_MODE_PWM:
342 if (pwm->pwm_set_intensity)
343 pwm->pwm_set_intensity(brt_val, max_brightness);
344 break;
345 default:
346 break;
347 }
348 }
349
350 static ssize_t lm3530_mode_get(struct device *dev,
351 struct device_attribute *attr, char *buf)
352 {
353 struct led_classdev *led_cdev = dev_get_drvdata(dev);
354 struct lm3530_data *drvdata;
355 int i, len = 0;
356
357 drvdata = container_of(led_cdev, struct lm3530_data, led_dev);
358 for (i = 0; i < ARRAY_SIZE(mode_map); i++)
359 if (drvdata->mode == mode_map[i].mode_val)
360 len += sprintf(buf + len, "[%s] ", mode_map[i].mode);
361 else
362 len += sprintf(buf + len, "%s ", mode_map[i].mode);
363
364 len += sprintf(buf + len, "\n");
365
366 return len;
367 }
368
369 static ssize_t lm3530_mode_set(struct device *dev, struct device_attribute
370 *attr, const char *buf, size_t size)
371 {
372 struct led_classdev *led_cdev = dev_get_drvdata(dev);
373 struct lm3530_data *drvdata;
374 struct lm3530_pwm_data *pwm;
375 u8 max_brightness;
376 int mode, err;
377
378 drvdata = container_of(led_cdev, struct lm3530_data, led_dev);
379 pwm = &drvdata->pdata->pwm_data;
380 max_brightness = led_cdev->max_brightness;
381 mode = lm3530_get_mode_from_str(buf);
382 if (mode < 0) {
383 dev_err(dev, "Invalid mode\n");
384 return mode;
385 }
386
387 drvdata->mode = mode;
388
389 /* set pwm to low if unnecessary */
390 if (mode != LM3530_BL_MODE_PWM && pwm->pwm_set_intensity)
391 pwm->pwm_set_intensity(0, max_brightness);
392
393 err = lm3530_init_registers(drvdata);
394 if (err) {
395 dev_err(dev, "Setting %s Mode failed :%d\n", buf, err);
396 return err;
397 }
398
399 return sizeof(drvdata->mode);
400 }
401 static DEVICE_ATTR(mode, 0644, lm3530_mode_get, lm3530_mode_set);
402
403 static int lm3530_probe(struct i2c_client *client,
404 const struct i2c_device_id *id)
405 {
406 struct lm3530_platform_data *pdata = dev_get_platdata(&client->dev);
407 struct lm3530_data *drvdata;
408 int err = 0;
409
410 if (pdata == NULL) {
411 dev_err(&client->dev, "platform data required\n");
412 return -ENODEV;
413 }
414
415 /* BL mode */
416 if (pdata->mode > LM3530_BL_MODE_PWM) {
417 dev_err(&client->dev, "Illegal Mode request\n");
418 return -EINVAL;
419 }
420
421 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
422 dev_err(&client->dev, "I2C_FUNC_I2C not supported\n");
423 return -EIO;
424 }
425
426 drvdata = devm_kzalloc(&client->dev, sizeof(struct lm3530_data),
427 GFP_KERNEL);
428 if (drvdata == NULL)
429 return -ENOMEM;
430
431 drvdata->mode = pdata->mode;
432 drvdata->client = client;
433 drvdata->pdata = pdata;
434 drvdata->brightness = LED_OFF;
435 drvdata->enable = false;
436 drvdata->led_dev.name = LM3530_LED_DEV;
437 drvdata->led_dev.brightness_set = lm3530_brightness_set;
438 drvdata->led_dev.max_brightness = MAX_BRIGHTNESS;
439
440 i2c_set_clientdata(client, drvdata);
441
442 drvdata->regulator = devm_regulator_get(&client->dev, "vin");
443 if (IS_ERR(drvdata->regulator)) {
444 dev_err(&client->dev, "regulator get failed\n");
445 err = PTR_ERR(drvdata->regulator);
446 drvdata->regulator = NULL;
447 return err;
448 }
449
450 if (drvdata->pdata->brt_val) {
451 err = lm3530_init_registers(drvdata);
452 if (err < 0) {
453 dev_err(&client->dev,
454 "Register Init failed: %d\n", err);
455 return err;
456 }
457 }
458 err = led_classdev_register(&client->dev, &drvdata->led_dev);
459 if (err < 0) {
460 dev_err(&client->dev, "Register led class failed: %d\n", err);
461 return err;
462 }
463
464 err = device_create_file(drvdata->led_dev.dev, &dev_attr_mode);
465 if (err < 0) {
466 dev_err(&client->dev, "File device creation failed: %d\n", err);
467 err = -ENODEV;
468 goto err_create_file;
469 }
470
471 return 0;
472
473 err_create_file:
474 led_classdev_unregister(&drvdata->led_dev);
475 return err;
476 }
477
478 static int lm3530_remove(struct i2c_client *client)
479 {
480 struct lm3530_data *drvdata = i2c_get_clientdata(client);
481
482 device_remove_file(drvdata->led_dev.dev, &dev_attr_mode);
483
484 lm3530_led_disable(drvdata);
485 led_classdev_unregister(&drvdata->led_dev);
486 return 0;
487 }
488
489 static const struct i2c_device_id lm3530_id[] = {
490 {LM3530_NAME, 0},
491 {}
492 };
493 MODULE_DEVICE_TABLE(i2c, lm3530_id);
494
495 static struct i2c_driver lm3530_i2c_driver = {
496 .probe = lm3530_probe,
497 .remove = lm3530_remove,
498 .id_table = lm3530_id,
499 .driver = {
500 .name = LM3530_NAME,
501 .owner = THIS_MODULE,
502 },
503 };
504
505 module_i2c_driver(lm3530_i2c_driver);
506
507 MODULE_DESCRIPTION("Back Light driver for LM3530");
508 MODULE_LICENSE("GPL v2");
509 MODULE_AUTHOR("Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>");
Linux with added FPC-III support