blob: 3dd7090a9a9b1f59c922b1e31c271d8581e38f0c [file] [log] [blame]
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -07001/*
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>
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -070020#include <linux/regulator/consumer.h>
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -070021
22#define LM3530_LED_DEV "lcd-backlight"
23#define LM3530_NAME "lm3530-led"
24
25#define LM3530_GEN_CONFIG 0x10
26#define LM3530_ALS_CONFIG 0x20
27#define LM3530_BRT_RAMP_RATE 0x30
28#define LM3530_ALS_ZONE_REG 0x40
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 15
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 */
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -070071#define LM3530_ALS_ZB_MAX (4)
72#define LM3530_ALS_WINDOW_mV (1000)
73#define LM3530_ALS_OFFSET_mV (4)
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -070074
75/* Zone Target Register defaults */
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -070076#define LM3530_DEF_ZT_0 (0x7F)
77#define LM3530_DEF_ZT_1 (0x66)
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -070078#define LM3530_DEF_ZT_2 (0x4C)
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -070079#define LM3530_DEF_ZT_3 (0x33)
80#define LM3530_DEF_ZT_4 (0x19)
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -070081
82struct lm3530_mode_map {
83 const char *mode;
84 enum lm3530_mode mode_val;
85};
86
87static struct lm3530_mode_map mode_map[] = {
88 { "man", LM3530_BL_MODE_MANUAL },
89 { "als", LM3530_BL_MODE_ALS },
90 { "pwm", LM3530_BL_MODE_PWM },
91};
92
93/**
94 * struct lm3530_data
95 * @led_dev: led class device
96 * @client: i2c client
97 * @pdata: LM3530 platform data
98 * @mode: mode of operation - manual, ALS, PWM
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -070099 * @regulator: regulator
100 * @brighness: previous brightness value
101 * @enable: regulator is enabled
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700102 */
103struct lm3530_data {
104 struct led_classdev led_dev;
105 struct i2c_client *client;
106 struct lm3530_platform_data *pdata;
107 enum lm3530_mode mode;
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700108 struct regulator *regulator;
109 enum led_brightness brightness;
110 bool enable;
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700111};
112
113static const u8 lm3530_reg[LM3530_REG_MAX] = {
114 LM3530_GEN_CONFIG,
115 LM3530_ALS_CONFIG,
116 LM3530_BRT_RAMP_RATE,
117 LM3530_ALS_ZONE_REG,
118 LM3530_ALS_IMP_SELECT,
119 LM3530_BRT_CTRL_REG,
120 LM3530_ALS_ZB0_REG,
121 LM3530_ALS_ZB1_REG,
122 LM3530_ALS_ZB2_REG,
123 LM3530_ALS_ZB3_REG,
124 LM3530_ALS_Z0T_REG,
125 LM3530_ALS_Z1T_REG,
126 LM3530_ALS_Z2T_REG,
127 LM3530_ALS_Z3T_REG,
128 LM3530_ALS_Z4T_REG,
129};
130
131static int lm3530_get_mode_from_str(const char *str)
132{
133 int i;
134
135 for (i = 0; i < ARRAY_SIZE(mode_map); i++)
136 if (sysfs_streq(str, mode_map[i].mode))
137 return mode_map[i].mode_val;
138
139 return -1;
140}
141
142static int lm3530_init_registers(struct lm3530_data *drvdata)
143{
144 int ret = 0;
145 int i;
146 u8 gen_config;
147 u8 als_config = 0;
148 u8 brt_ramp;
149 u8 als_imp_sel = 0;
150 u8 brightness;
151 u8 reg_val[LM3530_REG_MAX];
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -0700152 u8 zones[LM3530_ALS_ZB_MAX];
153 u32 als_vmin, als_vmax, als_vstep;
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700154 struct lm3530_platform_data *pltfm = drvdata->pdata;
155 struct i2c_client *client = drvdata->client;
156
157 gen_config = (pltfm->brt_ramp_law << LM3530_RAMP_LAW_SHIFT) |
158 ((pltfm->max_current & 7) << LM3530_MAX_CURR_SHIFT);
159
160 if (drvdata->mode == LM3530_BL_MODE_MANUAL ||
161 drvdata->mode == LM3530_BL_MODE_ALS)
162 gen_config |= (LM3530_ENABLE_I2C);
163
164 if (drvdata->mode == LM3530_BL_MODE_ALS) {
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -0700165 if (pltfm->als_vmax == 0) {
166 pltfm->als_vmin = als_vmin = 0;
167 pltfm->als_vmin = als_vmax = LM3530_ALS_WINDOW_mV;
168 }
169
170 als_vmin = pltfm->als_vmin;
171 als_vmax = pltfm->als_vmax;
172
173 if ((als_vmax - als_vmin) > LM3530_ALS_WINDOW_mV)
174 pltfm->als_vmax = als_vmax =
175 als_vmin + LM3530_ALS_WINDOW_mV;
176
177 /* n zone boundary makes n+1 zones */
178 als_vstep = (als_vmax - als_vmin) / (LM3530_ALS_ZB_MAX + 1);
179
180 for (i = 0; i < LM3530_ALS_ZB_MAX; i++)
181 zones[i] = (((als_vmin + LM3530_ALS_OFFSET_mV) +
182 als_vstep + (i * als_vstep)) * LED_FULL)
183 / 1000;
184
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700185 als_config =
186 (pltfm->als_avrg_time << LM3530_ALS_AVG_TIME_SHIFT) |
187 (LM3530_ENABLE_ALS) |
188 (pltfm->als_input_mode << LM3530_ALS_SEL_SHIFT);
189
190 als_imp_sel =
191 (pltfm->als1_resistor_sel << LM3530_ALS1_IMP_SHIFT) |
192 (pltfm->als2_resistor_sel << LM3530_ALS2_IMP_SHIFT);
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -0700193
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700194 }
195
196 if (drvdata->mode == LM3530_BL_MODE_PWM)
197 gen_config |= (LM3530_ENABLE_PWM) |
198 (pltfm->pwm_pol_hi << LM3530_PWM_POL_SHIFT) |
199 (LM3530_ENABLE_PWM_SIMPLE);
200
201 brt_ramp = (pltfm->brt_ramp_fall << LM3530_BRT_RAMP_FALL_SHIFT) |
202 (pltfm->brt_ramp_rise << LM3530_BRT_RAMP_RISE_SHIFT);
203
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700204 if (drvdata->brightness)
205 brightness = drvdata->brightness;
206 else
207 brightness = drvdata->brightness = pltfm->brt_val;
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700208
209 reg_val[0] = gen_config; /* LM3530_GEN_CONFIG */
210 reg_val[1] = als_config; /* LM3530_ALS_CONFIG */
211 reg_val[2] = brt_ramp; /* LM3530_BRT_RAMP_RATE */
212 reg_val[3] = 0x00; /* LM3530_ALS_ZONE_REG */
213 reg_val[4] = als_imp_sel; /* LM3530_ALS_IMP_SELECT */
214 reg_val[5] = brightness; /* LM3530_BRT_CTRL_REG */
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -0700215 reg_val[6] = zones[0]; /* LM3530_ALS_ZB0_REG */
216 reg_val[7] = zones[1]; /* LM3530_ALS_ZB1_REG */
217 reg_val[8] = zones[2]; /* LM3530_ALS_ZB2_REG */
218 reg_val[9] = zones[3]; /* LM3530_ALS_ZB3_REG */
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700219 reg_val[10] = LM3530_DEF_ZT_0; /* LM3530_ALS_Z0T_REG */
220 reg_val[11] = LM3530_DEF_ZT_1; /* LM3530_ALS_Z1T_REG */
221 reg_val[12] = LM3530_DEF_ZT_2; /* LM3530_ALS_Z2T_REG */
222 reg_val[13] = LM3530_DEF_ZT_3; /* LM3530_ALS_Z3T_REG */
223 reg_val[14] = LM3530_DEF_ZT_4; /* LM3530_ALS_Z4T_REG */
224
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700225 if (!drvdata->enable) {
226 ret = regulator_enable(drvdata->regulator);
227 if (ret) {
228 dev_err(&drvdata->client->dev,
229 "Enable regulator failed\n");
230 return ret;
231 }
232 drvdata->enable = true;
233 }
234
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700235 for (i = 0; i < LM3530_REG_MAX; i++) {
236 ret = i2c_smbus_write_byte_data(client,
237 lm3530_reg[i], reg_val[i]);
238 if (ret)
239 break;
240 }
241
242 return ret;
243}
244
245static void lm3530_brightness_set(struct led_classdev *led_cdev,
246 enum led_brightness brt_val)
247{
248 int err;
249 struct lm3530_data *drvdata =
250 container_of(led_cdev, struct lm3530_data, led_dev);
251
252 switch (drvdata->mode) {
253 case LM3530_BL_MODE_MANUAL:
254
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700255 if (!drvdata->enable) {
256 err = lm3530_init_registers(drvdata);
257 if (err) {
258 dev_err(&drvdata->client->dev,
259 "Register Init failed: %d\n", err);
260 break;
261 }
262 }
263
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700264 /* set the brightness in brightness control register*/
265 err = i2c_smbus_write_byte_data(drvdata->client,
266 LM3530_BRT_CTRL_REG, brt_val / 2);
267 if (err)
268 dev_err(&drvdata->client->dev,
269 "Unable to set brightness: %d\n", err);
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700270 else
271 drvdata->brightness = brt_val / 2;
272
273 if (brt_val == 0) {
274 err = regulator_disable(drvdata->regulator);
275 if (err)
276 dev_err(&drvdata->client->dev,
277 "Disable regulator failed\n");
278 drvdata->enable = false;
279 }
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700280 break;
281 case LM3530_BL_MODE_ALS:
282 break;
283 case LM3530_BL_MODE_PWM:
284 break;
285 default:
286 break;
287 }
288}
289
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -0700290static ssize_t lm3530_mode_get(struct device *dev,
291 struct device_attribute *attr, char *buf)
292{
293 struct i2c_client *client = container_of(
294 dev->parent, struct i2c_client, dev);
295 struct lm3530_data *drvdata = i2c_get_clientdata(client);
296 int i, len = 0;
297
298 for (i = 0; i < ARRAY_SIZE(mode_map); i++)
299 if (drvdata->mode == mode_map[i].mode_val)
300 len += sprintf(buf + len, "[%s] ", mode_map[i].mode);
301 else
302 len += sprintf(buf + len, "%s ", mode_map[i].mode);
303
304 len += sprintf(buf + len, "\n");
305
306 return len;
307}
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700308
309static ssize_t lm3530_mode_set(struct device *dev, struct device_attribute
310 *attr, const char *buf, size_t size)
311{
312 int err;
313 struct i2c_client *client = container_of(
314 dev->parent, struct i2c_client, dev);
315 struct lm3530_data *drvdata = i2c_get_clientdata(client);
316 int mode;
317
318 mode = lm3530_get_mode_from_str(buf);
319 if (mode < 0) {
320 dev_err(dev, "Invalid mode\n");
321 return -EINVAL;
322 }
323
324 if (mode == LM3530_BL_MODE_MANUAL)
325 drvdata->mode = LM3530_BL_MODE_MANUAL;
326 else if (mode == LM3530_BL_MODE_ALS)
327 drvdata->mode = LM3530_BL_MODE_ALS;
328 else if (mode == LM3530_BL_MODE_PWM) {
329 dev_err(dev, "PWM mode not supported\n");
330 return -EINVAL;
331 }
332
333 err = lm3530_init_registers(drvdata);
334 if (err) {
335 dev_err(dev, "Setting %s Mode failed :%d\n", buf, err);
336 return err;
337 }
338
339 return sizeof(drvdata->mode);
340}
Shreshtha Kumar Sahu40b14452011-07-25 17:13:17 -0700341static DEVICE_ATTR(mode, 0644, lm3530_mode_get, lm3530_mode_set);
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700342
343static int __devinit lm3530_probe(struct i2c_client *client,
344 const struct i2c_device_id *id)
345{
346 struct lm3530_platform_data *pdata = client->dev.platform_data;
347 struct lm3530_data *drvdata;
348 int err = 0;
349
350 if (pdata == NULL) {
351 dev_err(&client->dev, "platform data required\n");
352 err = -ENODEV;
353 goto err_out;
354 }
355
356 /* BL mode */
357 if (pdata->mode > LM3530_BL_MODE_PWM) {
358 dev_err(&client->dev, "Illegal Mode request\n");
359 err = -EINVAL;
360 goto err_out;
361 }
362
363 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
364 dev_err(&client->dev, "I2C_FUNC_I2C not supported\n");
365 err = -EIO;
366 goto err_out;
367 }
368
369 drvdata = kzalloc(sizeof(struct lm3530_data), GFP_KERNEL);
370 if (drvdata == NULL) {
371 err = -ENOMEM;
372 goto err_out;
373 }
374
375 drvdata->mode = pdata->mode;
376 drvdata->client = client;
377 drvdata->pdata = pdata;
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700378 drvdata->brightness = LED_OFF;
379 drvdata->enable = false;
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700380 drvdata->led_dev.name = LM3530_LED_DEV;
381 drvdata->led_dev.brightness_set = lm3530_brightness_set;
382
383 i2c_set_clientdata(client, drvdata);
384
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700385 drvdata->regulator = regulator_get(&client->dev, "vin");
386 if (IS_ERR(drvdata->regulator)) {
387 dev_err(&client->dev, "regulator get failed\n");
388 err = PTR_ERR(drvdata->regulator);
389 drvdata->regulator = NULL;
390 goto err_regulator_get;
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700391 }
392
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700393 if (drvdata->pdata->brt_val) {
394 err = lm3530_init_registers(drvdata);
395 if (err < 0) {
396 dev_err(&client->dev,
397 "Register Init failed: %d\n", err);
398 err = -ENODEV;
399 goto err_reg_init;
400 }
401 }
402 err = led_classdev_register(&client->dev, &drvdata->led_dev);
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700403 if (err < 0) {
404 dev_err(&client->dev, "Register led class failed: %d\n", err);
405 err = -ENODEV;
406 goto err_class_register;
407 }
408
409 err = device_create_file(drvdata->led_dev.dev, &dev_attr_mode);
410 if (err < 0) {
411 dev_err(&client->dev, "File device creation failed: %d\n", err);
412 err = -ENODEV;
413 goto err_create_file;
414 }
415
416 return 0;
417
418err_create_file:
419 led_classdev_unregister(&drvdata->led_dev);
420err_class_register:
421err_reg_init:
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700422 regulator_put(drvdata->regulator);
423err_regulator_get:
424 i2c_set_clientdata(client, NULL);
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700425 kfree(drvdata);
426err_out:
427 return err;
428}
429
430static int __devexit lm3530_remove(struct i2c_client *client)
431{
432 struct lm3530_data *drvdata = i2c_get_clientdata(client);
433
434 device_remove_file(drvdata->led_dev.dev, &dev_attr_mode);
Shreshtha Kumar Sahu9b2da532011-05-24 17:13:28 -0700435
436 if (drvdata->enable)
437 regulator_disable(drvdata->regulator);
438 regulator_put(drvdata->regulator);
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700439 led_classdev_unregister(&drvdata->led_dev);
440 kfree(drvdata);
441 return 0;
442}
443
444static const struct i2c_device_id lm3530_id[] = {
445 {LM3530_NAME, 0},
446 {}
447};
Axel Lind5f33d42011-05-17 15:44:09 -0700448MODULE_DEVICE_TABLE(i2c, lm3530_id);
Shreshtha Kumar Sahub1e6b702011-03-22 16:30:16 -0700449
450static struct i2c_driver lm3530_i2c_driver = {
451 .probe = lm3530_probe,
452 .remove = lm3530_remove,
453 .id_table = lm3530_id,
454 .driver = {
455 .name = LM3530_NAME,
456 .owner = THIS_MODULE,
457 },
458};
459
460static int __init lm3530_init(void)
461{
462 return i2c_add_driver(&lm3530_i2c_driver);
463}
464
465static void __exit lm3530_exit(void)
466{
467 i2c_del_driver(&lm3530_i2c_driver);
468}
469
470module_init(lm3530_init);
471module_exit(lm3530_exit);
472
473MODULE_DESCRIPTION("Back Light driver for LM3530");
474MODULE_LICENSE("GPL v2");
475MODULE_AUTHOR("Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>");