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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
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
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
63#define LM3530_BRT_RAMP_FALL_SHIFT (0)
64#define LM3530_BRT_RAMP_RISE_SHIFT (3)
65
66
67#define LM3530_ALS1_IMP_SHIFT (0)
68#define LM3530_ALS2_IMP_SHIFT (4)
69
70
71#define LM3530_ALS_ZB_MAX (4)
72#define LM3530_ALS_WINDOW_mV (1000)
73#define LM3530_ALS_OFFSET_mV (4)
74
75
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
83#define MAX_BRIGHTNESS (127)
84
85struct lm3530_mode_map {
86 const char *mode;
87 enum lm3530_mode mode_val;
88};
89
90static 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};
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105
106struct 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
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118
119
120
121
122struct lm3530_als_data {
123 u8 config;
124 u8 imp_sel;
125 u8 zones[LM3530_ALS_ZB_MAX];
126};
127
128static 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
145static 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
156static 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
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
190static 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
207static 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
224static 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;
268 reg_val[1] = als.config;
269 reg_val[2] = brt_ramp;
270 reg_val[3] = als.imp_sel;
271 reg_val[4] = brightness;
272 reg_val[5] = als.zones[0];
273 reg_val[6] = als.zones[1];
274 reg_val[7] = als.zones[2];
275 reg_val[8] = als.zones[3];
276 reg_val[9] = LM3530_DEF_ZT_0;
277 reg_val[10] = LM3530_DEF_ZT_1;
278 reg_val[11] = LM3530_DEF_ZT_2;
279 reg_val[12] = LM3530_DEF_ZT_3;
280 reg_val[13] = LM3530_DEF_ZT_4;
281
282 ret = lm3530_led_enable(drvdata);
283 if (ret)
284 return ret;
285
286 for (i = 0; i < LM3530_REG_MAX; i++) {
287
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
305static 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
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
350static 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
369static 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
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}
401static DEVICE_ATTR(mode, 0644, lm3530_mode_get, lm3530_mode_set);
402
403static struct attribute *lm3530_attrs[] = {
404 &dev_attr_mode.attr,
405 NULL
406};
407ATTRIBUTE_GROUPS(lm3530);
408
409static int lm3530_probe(struct i2c_client *client,
410 const struct i2c_device_id *id)
411{
412 struct lm3530_platform_data *pdata = dev_get_platdata(&client->dev);
413 struct lm3530_data *drvdata;
414 int err = 0;
415
416 if (pdata == NULL) {
417 dev_err(&client->dev, "platform data required\n");
418 return -ENODEV;
419 }
420
421
422 if (pdata->mode > LM3530_BL_MODE_PWM) {
423 dev_err(&client->dev, "Illegal Mode request\n");
424 return -EINVAL;
425 }
426
427 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
428 dev_err(&client->dev, "I2C_FUNC_I2C not supported\n");
429 return -EIO;
430 }
431
432 drvdata = devm_kzalloc(&client->dev, sizeof(struct lm3530_data),
433 GFP_KERNEL);
434 if (drvdata == NULL)
435 return -ENOMEM;
436
437 drvdata->mode = pdata->mode;
438 drvdata->client = client;
439 drvdata->pdata = pdata;
440 drvdata->brightness = LED_OFF;
441 drvdata->enable = false;
442 drvdata->led_dev.name = LM3530_LED_DEV;
443 drvdata->led_dev.brightness_set = lm3530_brightness_set;
444 drvdata->led_dev.max_brightness = MAX_BRIGHTNESS;
445 drvdata->led_dev.groups = lm3530_groups;
446
447 i2c_set_clientdata(client, drvdata);
448
449 drvdata->regulator = devm_regulator_get(&client->dev, "vin");
450 if (IS_ERR(drvdata->regulator)) {
451 dev_err(&client->dev, "regulator get failed\n");
452 err = PTR_ERR(drvdata->regulator);
453 drvdata->regulator = NULL;
454 return err;
455 }
456
457 if (drvdata->pdata->brt_val) {
458 err = lm3530_init_registers(drvdata);
459 if (err < 0) {
460 dev_err(&client->dev,
461 "Register Init failed: %d\n", err);
462 return err;
463 }
464 }
465 err = led_classdev_register(&client->dev, &drvdata->led_dev);
466 if (err < 0) {
467 dev_err(&client->dev, "Register led class failed: %d\n", err);
468 return err;
469 }
470
471 return 0;
472}
473
474static int lm3530_remove(struct i2c_client *client)
475{
476 struct lm3530_data *drvdata = i2c_get_clientdata(client);
477
478 lm3530_led_disable(drvdata);
479 led_classdev_unregister(&drvdata->led_dev);
480 return 0;
481}
482
483static const struct i2c_device_id lm3530_id[] = {
484 {LM3530_NAME, 0},
485 {}
486};
487MODULE_DEVICE_TABLE(i2c, lm3530_id);
488
489static struct i2c_driver lm3530_i2c_driver = {
490 .probe = lm3530_probe,
491 .remove = lm3530_remove,
492 .id_table = lm3530_id,
493 .driver = {
494 .name = LM3530_NAME,
495 .owner = THIS_MODULE,
496 },
497};
498
499module_i2c_driver(lm3530_i2c_driver);
500
501MODULE_DESCRIPTION("Back Light driver for LM3530");
502MODULE_LICENSE("GPL v2");
503MODULE_AUTHOR("Shreshtha Kumar SAHU <shreshthakumar.sahu@stericsson.com>");
504
