leds: Add new LED driver for lm355x chips

This driver is a general version for LM355x,lm3554 and lm3556,led chips of TI.

LM3554 :
The LM3554 is a 2 MHz fixed-frequency synchronous boost
converter with 1.2A dual high side led drivers.
Datasheet: www.ti.com/lit/ds/symlink/lm3554.pdf

LM3556 :
The LM3556 is a 4 MHz fixed-frequency synchronous boost
converter plus 1.5A constant current driver for a high-current white LED.
Datasheet: www.national.com/ds/LM/LM3556.pdf

(bryan.wu@canonical.com: use flush_work() to replace flush_work_sync() which is
deprecated)

Signed-off-by: G.Shark Jeong <gshark.jeong@gmail.com>
Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
diff --git a/drivers/leds/leds-lm355x.c b/drivers/leds/leds-lm355x.c
new file mode 100644
index 0000000..065ec01
--- /dev/null
+++ b/drivers/leds/leds-lm355x.c
@@ -0,0 +1,572 @@
+/*
+* Simple driver for Texas Instruments LM355x LED Flash driver chip
+* Copyright (C) 2012 Texas Instruments
+*
+* This program is free software; you can redistribute it and/or modify
+* it under the terms of the GNU General Public License version 2 as
+* published by the Free Software Foundation.
+*/
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+#include <linux/leds.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/fs.h>
+#include <linux/regmap.h>
+#include <linux/workqueue.h>
+#include <linux/platform_data/leds-lm355x.h>
+
+enum lm355x_type {
+	CHIP_LM3554 = 0,
+	CHIP_LM3556,
+};
+
+enum lm355x_regs {
+	REG_FLAG = 0,
+	REG_TORCH_CFG,
+	REG_TORCH_CTRL,
+	REG_STROBE_CFG,
+	REG_FLASH_CTRL,
+	REG_INDI_CFG,
+	REG_INDI_CTRL,
+	REG_OPMODE,
+	REG_MAX,
+};
+
+/* operation mode */
+enum lm355x_mode {
+	MODE_SHDN = 0,
+	MODE_INDIC,
+	MODE_TORCH,
+	MODE_FLASH
+};
+
+/* register map info. */
+struct lm355x_reg_data {
+	u8 regno;
+	u8 mask;
+	u8 shift;
+};
+
+struct lm355x_chip_data {
+	struct device *dev;
+	enum lm355x_type type;
+
+	struct led_classdev cdev_flash;
+	struct led_classdev cdev_torch;
+	struct led_classdev cdev_indicator;
+
+	struct work_struct work_flash;
+	struct work_struct work_torch;
+	struct work_struct work_indicator;
+
+	u8 br_flash;
+	u8 br_torch;
+	u8 br_indicator;
+
+	struct lm355x_platform_data *pdata;
+	struct regmap *regmap;
+	struct mutex lock;
+
+	unsigned int last_flag;
+	struct lm355x_reg_data *regs;
+};
+
+/* specific indicator function for lm3556 */
+enum lm3556_indic_pulse_time {
+	PULSE_TIME_0_MS = 0,
+	PULSE_TIME_32_MS,
+	PULSE_TIME_64_MS,
+	PULSE_TIME_92_MS,
+	PULSE_TIME_128_MS,
+	PULSE_TIME_160_MS,
+	PULSE_TIME_196_MS,
+	PULSE_TIME_224_MS,
+	PULSE_TIME_256_MS,
+	PULSE_TIME_288_MS,
+	PULSE_TIME_320_MS,
+	PULSE_TIME_352_MS,
+	PULSE_TIME_384_MS,
+	PULSE_TIME_416_MS,
+	PULSE_TIME_448_MS,
+	PULSE_TIME_480_MS,
+};
+
+enum lm3556_indic_n_blank {
+	INDIC_N_BLANK_0 = 0,
+	INDIC_N_BLANK_1,
+	INDIC_N_BLANK_2,
+	INDIC_N_BLANK_3,
+	INDIC_N_BLANK_4,
+	INDIC_N_BLANK_5,
+	INDIC_N_BLANK_6,
+	INDIC_N_BLANK_7,
+	INDIC_N_BLANK_8,
+	INDIC_N_BLANK_9,
+	INDIC_N_BLANK_10,
+	INDIC_N_BLANK_11,
+	INDIC_N_BLANK_12,
+	INDIC_N_BLANK_13,
+	INDIC_N_BLANK_14,
+	INDIC_N_BLANK_15,
+};
+
+enum lm3556_indic_period {
+	INDIC_PERIOD_0 = 0,
+	INDIC_PERIOD_1,
+	INDIC_PERIOD_2,
+	INDIC_PERIOD_3,
+	INDIC_PERIOD_4,
+	INDIC_PERIOD_5,
+	INDIC_PERIOD_6,
+	INDIC_PERIOD_7,
+};
+
+#define INDIC_PATTERN_SIZE 4
+
+struct indicator {
+	u8 blinking;
+	u8 period_cnt;
+};
+
+/* indicator pattern data only for lm3556 */
+static struct indicator indicator_pattern[INDIC_PATTERN_SIZE] = {
+	[0] = {(INDIC_N_BLANK_1 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_1},
+	[1] = {(INDIC_N_BLANK_15 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_2},
+	[2] = {(INDIC_N_BLANK_10 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_4},
+	[3] = {(INDIC_N_BLANK_5 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_7},
+};
+
+static struct lm355x_reg_data lm3554_regs[REG_MAX] = {
+	[REG_FLAG] = {0xD0, 0xBF, 0},
+	[REG_TORCH_CFG] = {0xE0, 0x80, 7},
+	[REG_TORCH_CTRL] = {0xA0, 0x38, 3},
+	[REG_STROBE_CFG] = {0xE0, 0x04, 2},
+	[REG_FLASH_CTRL] = {0xB0, 0x78, 3},
+	[REG_INDI_CFG] = {0xE0, 0x08, 3},
+	[REG_INDI_CTRL] = {0xA0, 0xC0, 6},
+	[REG_OPMODE] = {0xA0, 0x03, 0},
+};
+
+static struct lm355x_reg_data lm3556_regs[REG_MAX] = {
+	[REG_FLAG] = {0x0B, 0xFF, 0},
+	[REG_TORCH_CFG] = {0x0A, 0x10, 4},
+	[REG_TORCH_CTRL] = {0x09, 0x70, 4},
+	[REG_STROBE_CFG] = {0x0A, 0x20, 5},
+	[REG_FLASH_CTRL] = {0x09, 0x0F, 0},
+	[REG_INDI_CFG] = {0xFF, 0xFF, 0},
+	[REG_INDI_CTRL] = {0x09, 0x70, 4},
+	[REG_OPMODE] = {0x0A, 0x03, 0},
+};
+
+static char lm355x_name[][I2C_NAME_SIZE] = {
+	[CHIP_LM3554] = LM3554_NAME,
+	[CHIP_LM3556] = LM3556_NAME,
+};
+
+/* chip initialize */
+static int __devinit lm355x_chip_init(struct lm355x_chip_data *chip)
+{
+	int ret;
+	unsigned int reg_val;
+	struct lm355x_platform_data *pdata = chip->pdata;
+
+	/* input and output pins configuration */
+	switch (chip->type) {
+	case CHIP_LM3554:
+		reg_val = pdata->pin_tx2 | pdata->ntc_pin;
+		ret = regmap_update_bits(chip->regmap, 0xE0, 0x28, reg_val);
+		if (ret < 0)
+			goto out;
+		reg_val = pdata->pass_mode;
+		ret = regmap_update_bits(chip->regmap, 0xA0, 0x04, reg_val);
+		if (ret < 0)
+			goto out;
+		break;
+
+	case CHIP_LM3556:
+		reg_val = pdata->pin_tx2 | pdata->ntc_pin | pdata->pass_mode;
+		ret = regmap_update_bits(chip->regmap, 0x0A, 0xC4, reg_val);
+		if (ret < 0)
+			goto out;
+		break;
+	default:
+		return -ENODATA;
+	}
+
+	return ret;
+out:
+	dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
+	return ret;
+}
+
+/* chip control */
+static void lm355x_control(struct lm355x_chip_data *chip,
+			   u8 brightness, enum lm355x_mode opmode)
+{
+	int ret;
+	unsigned int reg_val;
+	struct lm355x_platform_data *pdata = chip->pdata;
+	struct lm355x_reg_data *preg = chip->regs;
+
+	ret = regmap_read(chip->regmap, preg[REG_FLAG].regno, &chip->last_flag);
+	if (ret < 0)
+		goto out;
+	if (chip->last_flag & preg[REG_FLAG].mask)
+		dev_info(chip->dev, "%s Last FLAG is 0x%x\n",
+			 lm355x_name[chip->type],
+			 chip->last_flag & preg[REG_FLAG].mask);
+	/* brightness 0 means shutdown */
+	if (!brightness)
+		opmode = MODE_SHDN;
+
+	switch (opmode) {
+	case MODE_TORCH:
+		ret =
+		    regmap_update_bits(chip->regmap, preg[REG_TORCH_CTRL].regno,
+				       preg[REG_TORCH_CTRL].mask,
+				       (brightness - 1)
+				       << preg[REG_TORCH_CTRL].shift);
+		if (ret < 0)
+			goto out;
+
+		if (pdata->pin_tx1 != LM355x_PIN_TORCH_DISABLE) {
+			ret =
+			    regmap_update_bits(chip->regmap,
+					       preg[REG_TORCH_CFG].regno,
+					       preg[REG_TORCH_CFG].mask,
+					       0x01 <<
+					       preg[REG_TORCH_CFG].shift);
+			if (ret < 0)
+				goto out;
+			opmode = MODE_SHDN;
+			dev_info(chip->dev,
+				 "torch brt is set - ext. torch pin mode\n");
+		}
+		break;
+
+	case MODE_FLASH:
+
+		ret =
+		    regmap_update_bits(chip->regmap, preg[REG_FLASH_CTRL].regno,
+				       preg[REG_FLASH_CTRL].mask,
+				       (brightness - 1)
+				       << preg[REG_FLASH_CTRL].shift);
+		if (ret < 0)
+			goto out;
+
+		if (pdata->pin_strobe != LM355x_PIN_STROBE_DISABLE) {
+			if (chip->type == CHIP_LM3554)
+				reg_val = 0x00;
+			else
+				reg_val = 0x01;
+			ret =
+			    regmap_update_bits(chip->regmap,
+					       preg[REG_STROBE_CFG].regno,
+					       preg[REG_STROBE_CFG].mask,
+					       reg_val <<
+					       preg[REG_STROBE_CFG].shift);
+			if (ret < 0)
+				goto out;
+			opmode = MODE_SHDN;
+			dev_info(chip->dev,
+				 "flash brt is set - ext. strobe pin mode\n");
+		}
+		break;
+
+	case MODE_INDIC:
+		ret =
+		    regmap_update_bits(chip->regmap, preg[REG_INDI_CTRL].regno,
+				       preg[REG_INDI_CTRL].mask,
+				       (brightness - 1)
+				       << preg[REG_INDI_CTRL].shift);
+		if (ret < 0)
+			goto out;
+
+		if (pdata->pin_tx2 != LM355x_PIN_TX_DISABLE) {
+			ret =
+			    regmap_update_bits(chip->regmap,
+					       preg[REG_INDI_CFG].regno,
+					       preg[REG_INDI_CFG].mask,
+					       0x01 <<
+					       preg[REG_INDI_CFG].shift);
+			if (ret < 0)
+				goto out;
+			opmode = MODE_SHDN;
+		}
+		break;
+	case MODE_SHDN:
+		break;
+	default:
+		return;
+	}
+	/* operation mode control */
+	ret = regmap_update_bits(chip->regmap, preg[REG_OPMODE].regno,
+				 preg[REG_OPMODE].mask,
+				 opmode << preg[REG_OPMODE].shift);
+	if (ret < 0)
+		goto out;
+	return;
+out:
+	dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
+	return;
+}
+
+/* torch */
+static void lm355x_deferred_torch_brightness_set(struct work_struct *work)
+{
+	struct lm355x_chip_data *chip =
+	    container_of(work, struct lm355x_chip_data, work_torch);
+
+	mutex_lock(&chip->lock);
+	lm355x_control(chip, chip->br_torch, MODE_TORCH);
+	mutex_unlock(&chip->lock);
+}
+
+static void lm355x_torch_brightness_set(struct led_classdev *cdev,
+					enum led_brightness brightness)
+{
+	struct lm355x_chip_data *chip =
+	    container_of(cdev, struct lm355x_chip_data, cdev_torch);
+
+	chip->br_torch = brightness;
+	schedule_work(&chip->work_torch);
+}
+
+/* flash */
+static void lm355x_deferred_strobe_brightness_set(struct work_struct *work)
+{
+	struct lm355x_chip_data *chip =
+	    container_of(work, struct lm355x_chip_data, work_flash);
+
+	mutex_lock(&chip->lock);
+	lm355x_control(chip, chip->br_flash, MODE_FLASH);
+	mutex_unlock(&chip->lock);
+}
+
+static void lm355x_strobe_brightness_set(struct led_classdev *cdev,
+					 enum led_brightness brightness)
+{
+	struct lm355x_chip_data *chip =
+	    container_of(cdev, struct lm355x_chip_data, cdev_flash);
+
+	chip->br_flash = brightness;
+	schedule_work(&chip->work_flash);
+}
+
+/* indicator */
+static void lm355x_deferred_indicator_brightness_set(struct work_struct *work)
+{
+	struct lm355x_chip_data *chip =
+	    container_of(work, struct lm355x_chip_data, work_indicator);
+
+	mutex_lock(&chip->lock);
+	lm355x_control(chip, chip->br_indicator, MODE_INDIC);
+	mutex_unlock(&chip->lock);
+}
+
+static void lm355x_indicator_brightness_set(struct led_classdev *cdev,
+					    enum led_brightness brightness)
+{
+	struct lm355x_chip_data *chip =
+	    container_of(cdev, struct lm355x_chip_data, cdev_indicator);
+
+	chip->br_indicator = brightness;
+	schedule_work(&chip->work_indicator);
+}
+
+/* indicator pattern only for lm3556*/
+static ssize_t lm3556_indicator_pattern_store(struct device *dev,
+					      struct device_attribute *devAttr,
+					      const char *buf, size_t size)
+{
+	ssize_t ret;
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	struct lm355x_chip_data *chip =
+	    container_of(led_cdev, struct lm355x_chip_data, cdev_indicator);
+	unsigned int state;
+
+	ret = kstrtouint(buf, 10, &state);
+	if (ret)
+		goto out;
+	if (state > INDIC_PATTERN_SIZE - 1)
+		state = INDIC_PATTERN_SIZE - 1;
+
+	ret = regmap_write(chip->regmap, 0x04,
+			   indicator_pattern[state].blinking);
+	if (ret < 0)
+		goto out;
+
+	ret = regmap_write(chip->regmap, 0x05,
+			   indicator_pattern[state].period_cnt);
+	if (ret < 0)
+		goto out;
+
+	return size;
+out:
+	dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
+	return size;
+}
+
+static DEVICE_ATTR(pattern, 0666, NULL, lm3556_indicator_pattern_store);
+
+static const struct regmap_config lm355x_regmap = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0xFF,
+};
+
+/* module initialize */
+static int __devinit lm355x_probe(struct i2c_client *client,
+				  const struct i2c_device_id *id)
+{
+	struct lm355x_platform_data *pdata = client->dev.platform_data;
+	struct lm355x_chip_data *chip;
+
+	int err;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "i2c functionality check fail.\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (pdata == NULL) {
+		dev_err(&client->dev, "needs Platform Data.\n");
+		return -ENODATA;
+	}
+
+	chip = devm_kzalloc(&client->dev,
+			    sizeof(struct lm355x_chip_data), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->dev = &client->dev;
+	chip->type = id->driver_data;
+	switch (id->driver_data) {
+	case CHIP_LM3554:
+		chip->regs = lm3554_regs;
+		break;
+	case CHIP_LM3556:
+		chip->regs = lm3556_regs;
+		break;
+	default:
+		return -ENOSYS;
+	}
+	chip->pdata = pdata;
+
+	chip->regmap = devm_regmap_init_i2c(client, &lm355x_regmap);
+	if (IS_ERR(chip->regmap)) {
+		err = PTR_ERR(chip->regmap);
+		dev_err(&client->dev,
+			"Failed to allocate register map: %d\n", err);
+		return err;
+	}
+
+	mutex_init(&chip->lock);
+	i2c_set_clientdata(client, chip);
+
+	err = lm355x_chip_init(chip);
+	if (err < 0)
+		goto err_out;
+
+	/* flash */
+	INIT_WORK(&chip->work_flash, lm355x_deferred_strobe_brightness_set);
+	chip->cdev_flash.name = "flash";
+	chip->cdev_flash.max_brightness = 16;
+	chip->cdev_flash.brightness_set = lm355x_strobe_brightness_set;
+	err = led_classdev_register((struct device *)
+				    &client->dev, &chip->cdev_flash);
+	if (err < 0)
+		goto err_out;
+	/* torch */
+	INIT_WORK(&chip->work_torch, lm355x_deferred_torch_brightness_set);
+	chip->cdev_torch.name = "torch";
+	chip->cdev_torch.max_brightness = 8;
+	chip->cdev_torch.brightness_set = lm355x_torch_brightness_set;
+	err = led_classdev_register((struct device *)
+				    &client->dev, &chip->cdev_torch);
+	if (err < 0)
+		goto err_create_torch_file;
+	/* indicator */
+	INIT_WORK(&chip->work_indicator,
+		  lm355x_deferred_indicator_brightness_set);
+	chip->cdev_indicator.name = "indicator";
+	if (id->driver_data == CHIP_LM3554)
+		chip->cdev_indicator.max_brightness = 4;
+	else
+		chip->cdev_indicator.max_brightness = 8;
+	chip->cdev_indicator.brightness_set = lm355x_indicator_brightness_set;
+	err = led_classdev_register((struct device *)
+				    &client->dev, &chip->cdev_indicator);
+	if (err < 0)
+		goto err_create_indicator_file;
+	/* indicator pattern control only for LM3554 */
+	if (id->driver_data == CHIP_LM3556) {
+		err =
+		    device_create_file(chip->cdev_indicator.dev,
+				       &dev_attr_pattern);
+		if (err < 0)
+			goto err_create_pattern_file;
+	}
+
+	dev_info(&client->dev, "%s is initialized\n",
+		 lm355x_name[id->driver_data]);
+	return 0;
+
+err_create_pattern_file:
+	led_classdev_unregister(&chip->cdev_indicator);
+err_create_indicator_file:
+	led_classdev_unregister(&chip->cdev_torch);
+err_create_torch_file:
+	led_classdev_unregister(&chip->cdev_flash);
+err_out:
+	return err;
+}
+
+static int __devexit lm355x_remove(struct i2c_client *client)
+{
+	struct lm355x_chip_data *chip = i2c_get_clientdata(client);
+	struct lm355x_reg_data *preg = chip->regs;
+
+	regmap_write(chip->regmap, preg[REG_OPMODE].regno, 0);
+	if (chip->type == CHIP_LM3556)
+		device_remove_file(chip->cdev_indicator.dev, &dev_attr_pattern);
+	led_classdev_unregister(&chip->cdev_indicator);
+	flush_work(&chip->work_indicator);
+	led_classdev_unregister(&chip->cdev_torch);
+	flush_work(&chip->work_torch);
+	led_classdev_unregister(&chip->cdev_flash);
+	flush_work(&chip->work_flash);
+	dev_info(&client->dev, "%s is removed\n", lm355x_name[chip->type]);
+
+	return 0;
+}
+
+static const struct i2c_device_id lm355x_id[] = {
+	{LM3554_NAME, CHIP_LM3554},
+	{LM3556_NAME, CHIP_LM3556},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, lm355x_id);
+
+static struct i2c_driver lm355x_i2c_driver = {
+	.driver = {
+		   .name = LM355x_NAME,
+		   .owner = THIS_MODULE,
+		   .pm = NULL,
+		   },
+	.probe = lm355x_probe,
+	.remove = __devexit_p(lm355x_remove),
+	.id_table = lm355x_id,
+};
+
+module_i2c_driver(lm355x_i2c_driver);
+
+MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM355x");
+MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
+MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
+MODULE_LICENSE("GPL v2");