2 * Simple driver for Texas Instruments LM3639 Backlight + Flash LED driver chip
3 * Copyright (C) 2012 Texas Instruments
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/i2c.h>
13 #include <linux/leds.h>
14 #include <linux/backlight.h>
15 #include <linux/err.h>
16 #include <linux/delay.h>
17 #include <linux/uaccess.h>
18 #include <linux/interrupt.h>
19 #include <linux/regmap.h>
20 #include <linux/platform_data/lm3639_bl.h>
22 #define REG_DEV_ID 0x00
23 #define REG_CHECKSUM 0x01
24 #define REG_BL_CONF_1 0x02
25 #define REG_BL_CONF_2 0x03
26 #define REG_BL_CONF_3 0x04
27 #define REG_BL_CONF_4 0x05
28 #define REG_FL_CONF_1 0x06
29 #define REG_FL_CONF_2 0x07
30 #define REG_FL_CONF_3 0x08
31 #define REG_IO_CTRL 0x09
32 #define REG_ENABLE 0x0A
34 #define REG_MAX REG_FLAG
36 struct lm3639_chip_data {
38 struct lm3639_platform_data *pdata;
40 struct backlight_device *bled;
41 struct led_classdev cdev_flash;
42 struct led_classdev cdev_torch;
43 struct regmap *regmap;
45 unsigned int bled_mode;
46 unsigned int bled_map;
47 unsigned int last_flag;
51 static int lm3639_chip_init(struct lm3639_chip_data *pchip)
55 struct lm3639_platform_data *pdata = pchip->pdata;
57 /* input pins config. */
59 regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x08,
64 reg_val = (pdata->pin_pwm & 0x40) | pdata->pin_strobe | pdata->pin_tx;
65 ret = regmap_update_bits(pchip->regmap, REG_IO_CTRL, 0x7C, reg_val);
70 ret = regmap_write(pchip->regmap, REG_BL_CONF_4, pdata->init_brt_led);
74 ret = regmap_write(pchip->regmap, REG_BL_CONF_3, pdata->init_brt_led);
78 /* output pins config. */
79 if (!pdata->init_brt_led)
80 reg_val = pdata->fled_pins | pdata->bled_pins;
82 reg_val = pdata->fled_pins | pdata->bled_pins | 0x01;
84 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x79, reg_val);
90 dev_err(pchip->dev, "i2c failed to access register\n");
94 /* update and get brightness */
95 static int lm3639_bled_update_status(struct backlight_device *bl)
99 struct lm3639_chip_data *pchip = bl_get_data(bl);
100 struct lm3639_platform_data *pdata = pchip->pdata;
102 ret = regmap_read(pchip->regmap, REG_FLAG, ®_val);
107 dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
110 if (pdata->pin_pwm) {
111 if (pdata->pwm_set_intensity)
112 pdata->pwm_set_intensity(bl->props.brightness,
116 "No pwm control func. in plat-data\n");
117 return bl->props.brightness;
120 /* i2c control and set brigtness */
121 ret = regmap_write(pchip->regmap, REG_BL_CONF_4, bl->props.brightness);
124 ret = regmap_write(pchip->regmap, REG_BL_CONF_3, bl->props.brightness);
128 if (!bl->props.brightness)
129 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x00);
131 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x01, 0x01);
135 return bl->props.brightness;
137 dev_err(pchip->dev, "i2c failed to access registers\n");
138 return bl->props.brightness;
141 static int lm3639_bled_get_brightness(struct backlight_device *bl)
144 unsigned int reg_val;
145 struct lm3639_chip_data *pchip = bl_get_data(bl);
146 struct lm3639_platform_data *pdata = pchip->pdata;
148 if (pdata->pin_pwm) {
149 if (pdata->pwm_get_intensity)
150 bl->props.brightness = pdata->pwm_get_intensity();
153 "No pwm control func. in plat-data\n");
154 return bl->props.brightness;
157 ret = regmap_read(pchip->regmap, REG_BL_CONF_1, ®_val);
161 ret = regmap_read(pchip->regmap, REG_BL_CONF_4, ®_val);
163 ret = regmap_read(pchip->regmap, REG_BL_CONF_3, ®_val);
166 bl->props.brightness = reg_val;
168 return bl->props.brightness;
170 dev_err(pchip->dev, "i2c failed to access register\n");
171 return bl->props.brightness;
174 static const struct backlight_ops lm3639_bled_ops = {
175 .options = BL_CORE_SUSPENDRESUME,
176 .update_status = lm3639_bled_update_status,
177 .get_brightness = lm3639_bled_get_brightness,
180 /* backlight mapping mode */
181 static ssize_t lm3639_bled_mode_store(struct device *dev,
182 struct device_attribute *devAttr,
183 const char *buf, size_t size)
186 struct lm3639_chip_data *pchip = dev_get_drvdata(dev);
189 ret = kstrtouint(buf, 10, &state);
195 regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
199 regmap_update_bits(pchip->regmap, REG_BL_CONF_1, 0x10,
208 dev_err(pchip->dev, "%s:i2c access fail to register\n", __func__);
212 dev_err(pchip->dev, "%s:input conversion fail\n", __func__);
217 static DEVICE_ATTR(bled_mode, 0666, NULL, lm3639_bled_mode_store);
220 static void lm3639_torch_brightness_set(struct led_classdev *cdev,
221 enum led_brightness brightness)
224 unsigned int reg_val;
225 struct lm3639_chip_data *pchip;
227 pchip = container_of(cdev, struct lm3639_chip_data, cdev_torch);
229 ret = regmap_read(pchip->regmap, REG_FLAG, ®_val);
233 dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
235 /* brightness 0 means off state */
237 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
243 ret = regmap_update_bits(pchip->regmap,
244 REG_FL_CONF_1, 0x70, (brightness - 1) << 4);
247 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x02);
253 dev_err(pchip->dev, "i2c failed to access register\n");
258 static void lm3639_flash_brightness_set(struct led_classdev *cdev,
259 enum led_brightness brightness)
262 unsigned int reg_val;
263 struct lm3639_chip_data *pchip;
265 pchip = container_of(cdev, struct lm3639_chip_data, cdev_flash);
267 ret = regmap_read(pchip->regmap, REG_FLAG, ®_val);
271 dev_info(pchip->dev, "last flag is 0x%x\n", reg_val);
273 /* torch off before flash control */
274 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x00);
278 /* brightness 0 means off state */
282 ret = regmap_update_bits(pchip->regmap,
283 REG_FL_CONF_1, 0x0F, brightness - 1);
286 ret = regmap_update_bits(pchip->regmap, REG_ENABLE, 0x06, 0x06);
292 dev_err(pchip->dev, "i2c failed to access register\n");
296 static const struct regmap_config lm3639_regmap = {
299 .max_register = REG_MAX,
302 static int lm3639_probe(struct i2c_client *client,
303 const struct i2c_device_id *id)
306 struct lm3639_chip_data *pchip;
307 struct lm3639_platform_data *pdata = client->dev.platform_data;
308 struct backlight_properties props;
310 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
311 dev_err(&client->dev, "i2c functionality check fail.\n");
316 dev_err(&client->dev, "Needs Platform Data.\n");
320 pchip = devm_kzalloc(&client->dev,
321 sizeof(struct lm3639_chip_data), GFP_KERNEL);
325 pchip->pdata = pdata;
326 pchip->dev = &client->dev;
328 pchip->regmap = devm_regmap_init_i2c(client, &lm3639_regmap);
329 if (IS_ERR(pchip->regmap)) {
330 ret = PTR_ERR(pchip->regmap);
331 dev_err(&client->dev, "fail : allocate register map: %d\n",
335 i2c_set_clientdata(client, pchip);
337 /* chip initialize */
338 ret = lm3639_chip_init(pchip);
340 dev_err(&client->dev, "fail : chip init\n");
345 props.type = BACKLIGHT_RAW;
346 props.brightness = pdata->init_brt_led;
347 props.max_brightness = pdata->max_brt_led;
349 backlight_device_register("lm3639_bled", pchip->dev, pchip,
350 &lm3639_bled_ops, &props);
351 if (IS_ERR(pchip->bled)) {
352 dev_err(&client->dev, "fail : backlight register\n");
357 ret = device_create_file(&(pchip->bled->dev), &dev_attr_bled_mode);
359 dev_err(&client->dev, "failed : add sysfs entries\n");
365 pchip->cdev_flash.name = "lm3639_flash";
366 pchip->cdev_flash.max_brightness = 16;
367 pchip->cdev_flash.brightness_set = lm3639_flash_brightness_set;
368 ret = led_classdev_register((struct device *)
369 &client->dev, &pchip->cdev_flash);
371 dev_err(&client->dev, "fail : flash register\n");
377 pchip->cdev_torch.name = "lm3639_torch";
378 pchip->cdev_torch.max_brightness = 8;
379 pchip->cdev_torch.brightness_set = lm3639_torch_brightness_set;
380 ret = led_classdev_register((struct device *)
381 &client->dev, &pchip->cdev_torch);
383 dev_err(&client->dev, "fail : torch register\n");
391 led_classdev_unregister(&pchip->cdev_flash);
393 device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
395 backlight_device_unregister(pchip->bled);
400 static int lm3639_remove(struct i2c_client *client)
402 struct lm3639_chip_data *pchip = i2c_get_clientdata(client);
404 regmap_write(pchip->regmap, REG_ENABLE, 0x00);
406 if (&pchip->cdev_torch)
407 led_classdev_unregister(&pchip->cdev_torch);
408 if (&pchip->cdev_flash)
409 led_classdev_unregister(&pchip->cdev_flash);
411 device_remove_file(&(pchip->bled->dev), &dev_attr_bled_mode);
412 backlight_device_unregister(pchip->bled);
417 static const struct i2c_device_id lm3639_id[] = {
422 MODULE_DEVICE_TABLE(i2c, lm3639_id);
423 static struct i2c_driver lm3639_i2c_driver = {
427 .probe = lm3639_probe,
428 .remove = lm3639_remove,
429 .id_table = lm3639_id,
432 module_i2c_driver(lm3639_i2c_driver);
434 MODULE_DESCRIPTION("Texas Instruments Backlight+Flash LED driver for LM3639");
435 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
436 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
437 MODULE_LICENSE("GPL v2");