// SPDX-License-Identifier: GPL-2.0-only

  /*
   * LP5562 LED driver
   *
   * Copyright (C) 2013 Texas Instruments
   *
   * Author: Milo(Woogyom) Kim <milo.kim@ti.com>

   */
  
  #include <linux/delay.h>
  #include <linux/firmware.h>
  #include <linux/i2c.h>

  #include <linux/leds.h>
  #include <linux/module.h>
  #include <linux/mutex.h>

  #include <linux/of.h>

  #include <linux/platform_data/leds-lp55xx.h>
  #include <linux/slab.h>
  
  #include "leds-lp55xx-common.h"
  
  #define LP5562_PROGRAM_LENGTH		32
  #define LP5562_MAX_LEDS			4
  
  /* ENABLE Register 00h */
  #define LP5562_REG_ENABLE		0x00
  #define LP5562_EXEC_ENG1_M		0x30
  #define LP5562_EXEC_ENG2_M		0x0C
  #define LP5562_EXEC_ENG3_M		0x03
  #define LP5562_EXEC_M			0x3F
  #define LP5562_MASTER_ENABLE		0x40	/* Chip master enable */
  #define LP5562_LOGARITHMIC_PWM		0x80	/* Logarithmic PWM adjustment */
  #define LP5562_EXEC_RUN			0x2A
  #define LP5562_ENABLE_DEFAULT	\
  	(LP5562_MASTER_ENABLE | LP5562_LOGARITHMIC_PWM)
  #define LP5562_ENABLE_RUN_PROGRAM	\
  	(LP5562_ENABLE_DEFAULT | LP5562_EXEC_RUN)
  
  /* OPMODE Register 01h */
  #define LP5562_REG_OP_MODE		0x01
  #define LP5562_MODE_ENG1_M		0x30
  #define LP5562_MODE_ENG2_M		0x0C
  #define LP5562_MODE_ENG3_M		0x03
  #define LP5562_LOAD_ENG1		0x10
  #define LP5562_LOAD_ENG2		0x04
  #define LP5562_LOAD_ENG3		0x01
  #define LP5562_RUN_ENG1			0x20
  #define LP5562_RUN_ENG2			0x08
  #define LP5562_RUN_ENG3			0x02
  #define LP5562_ENG1_IS_LOADING(mode)	\
  	((mode & LP5562_MODE_ENG1_M) == LP5562_LOAD_ENG1)
  #define LP5562_ENG2_IS_LOADING(mode)	\
  	((mode & LP5562_MODE_ENG2_M) == LP5562_LOAD_ENG2)
  #define LP5562_ENG3_IS_LOADING(mode)	\
  	((mode & LP5562_MODE_ENG3_M) == LP5562_LOAD_ENG3)
  
  /* BRIGHTNESS Registers */
  #define LP5562_REG_R_PWM		0x04
  #define LP5562_REG_G_PWM		0x03
  #define LP5562_REG_B_PWM		0x02
  #define LP5562_REG_W_PWM		0x0E
  
  /* CURRENT Registers */
  #define LP5562_REG_R_CURRENT		0x07
  #define LP5562_REG_G_CURRENT		0x06
  #define LP5562_REG_B_CURRENT		0x05
  #define LP5562_REG_W_CURRENT		0x0F
  
  /* CONFIG Register 08h */
  #define LP5562_REG_CONFIG		0x08

  #define LP5562_PWM_HF			0x40
  #define LP5562_PWRSAVE_EN		0x20
  #define LP5562_CLK_INT			0x01	/* Internal clock */
  #define LP5562_DEFAULT_CFG		(LP5562_PWM_HF | LP5562_PWRSAVE_EN)

  
  /* RESET Register 0Dh */
  #define LP5562_REG_RESET		0x0D
  #define LP5562_RESET			0xFF
  
  /* PROGRAM ENGINE Registers */
  #define LP5562_REG_PROG_MEM_ENG1	0x10
  #define LP5562_REG_PROG_MEM_ENG2	0x30
  #define LP5562_REG_PROG_MEM_ENG3	0x50
  
  /* LEDMAP Register 70h */
  #define LP5562_REG_ENG_SEL		0x70
  #define LP5562_ENG_SEL_PWM		0
  #define LP5562_ENG_FOR_RGB_M		0x3F
  #define LP5562_ENG_SEL_RGB		0x1B	/* R:ENG1, G:ENG2, B:ENG3 */
  #define LP5562_ENG_FOR_W_M		0xC0
  #define LP5562_ENG1_FOR_W		0x40	/* W:ENG1 */
  #define LP5562_ENG2_FOR_W		0x80	/* W:ENG2 */
  #define LP5562_ENG3_FOR_W		0xC0	/* W:ENG3 */
  
  /* Program Commands */
  #define LP5562_CMD_DISABLE		0x00
  #define LP5562_CMD_LOAD			0x15
  #define LP5562_CMD_RUN			0x2A
  #define LP5562_CMD_DIRECT		0x3F
  #define LP5562_PATTERN_OFF		0
  
  static inline void lp5562_wait_opmode_done(void)
  {
  	/* operation mode change needs to be longer than 153 us */
  	usleep_range(200, 300);
  }
  
  static inline void lp5562_wait_enable_done(void)
  {
  	/* it takes more 488 us to update ENABLE register */
  	usleep_range(500, 600);
  }
  
  static void lp5562_set_led_current(struct lp55xx_led *led, u8 led_current)
  {

  	static const u8 addr[] = {

  		LP5562_REG_R_CURRENT,
  		LP5562_REG_G_CURRENT,
  		LP5562_REG_B_CURRENT,
  		LP5562_REG_W_CURRENT,
  	};
  
  	led->led_current = led_current;
  	lp55xx_write(led->chip, addr[led->chan_nr], led_current);
  }
  
  static void lp5562_load_engine(struct lp55xx_chip *chip)
  {
  	enum lp55xx_engine_index idx = chip->engine_idx;

  	static const u8 mask[] = {

  		[LP55XX_ENGINE_1] = LP5562_MODE_ENG1_M,
  		[LP55XX_ENGINE_2] = LP5562_MODE_ENG2_M,
  		[LP55XX_ENGINE_3] = LP5562_MODE_ENG3_M,
  	};

  	static const u8 val[] = {

  		[LP55XX_ENGINE_1] = LP5562_LOAD_ENG1,
  		[LP55XX_ENGINE_2] = LP5562_LOAD_ENG2,
  		[LP55XX_ENGINE_3] = LP5562_LOAD_ENG3,
  	};
  
  	lp55xx_update_bits(chip, LP5562_REG_OP_MODE, mask[idx], val[idx]);
  
  	lp5562_wait_opmode_done();
  }
  
  static void lp5562_stop_engine(struct lp55xx_chip *chip)
  {
  	lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DISABLE);
  	lp5562_wait_opmode_done();
  }
  
  static void lp5562_run_engine(struct lp55xx_chip *chip, bool start)
  {
  	int ret;
  	u8 mode;
  	u8 exec;
  
  	/* stop engine */
  	if (!start) {
  		lp55xx_write(chip, LP5562_REG_ENABLE, LP5562_ENABLE_DEFAULT);
  		lp5562_wait_enable_done();
  		lp5562_stop_engine(chip);
  		lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
  		lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
  		lp5562_wait_opmode_done();
  		return;
  	}
  
  	/*
  	 * To run the engine,
  	 * operation mode and enable register should updated at the same time
  	 */
  
  	ret = lp55xx_read(chip, LP5562_REG_OP_MODE, &mode);
  	if (ret)
  		return;
  
  	ret = lp55xx_read(chip, LP5562_REG_ENABLE, &exec);
  	if (ret)
  		return;
  
  	/* change operation mode to RUN only when each engine is loading */
  	if (LP5562_ENG1_IS_LOADING(mode)) {
  		mode = (mode & ~LP5562_MODE_ENG1_M) | LP5562_RUN_ENG1;
  		exec = (exec & ~LP5562_EXEC_ENG1_M) | LP5562_RUN_ENG1;
  	}
  
  	if (LP5562_ENG2_IS_LOADING(mode)) {
  		mode = (mode & ~LP5562_MODE_ENG2_M) | LP5562_RUN_ENG2;
  		exec = (exec & ~LP5562_EXEC_ENG2_M) | LP5562_RUN_ENG2;
  	}
  
  	if (LP5562_ENG3_IS_LOADING(mode)) {
  		mode = (mode & ~LP5562_MODE_ENG3_M) | LP5562_RUN_ENG3;
  		exec = (exec & ~LP5562_EXEC_ENG3_M) | LP5562_RUN_ENG3;
  	}
  
  	lp55xx_write(chip, LP5562_REG_OP_MODE, mode);
  	lp5562_wait_opmode_done();
  
  	lp55xx_update_bits(chip, LP5562_REG_ENABLE, LP5562_EXEC_M, exec);
  	lp5562_wait_enable_done();
  }
  
  static int lp5562_update_firmware(struct lp55xx_chip *chip,
  					const u8 *data, size_t size)
  {
  	enum lp55xx_engine_index idx = chip->engine_idx;
  	u8 pattern[LP5562_PROGRAM_LENGTH] = {0};

  	static const u8 addr[] = {

  		[LP55XX_ENGINE_1] = LP5562_REG_PROG_MEM_ENG1,
  		[LP55XX_ENGINE_2] = LP5562_REG_PROG_MEM_ENG2,
  		[LP55XX_ENGINE_3] = LP5562_REG_PROG_MEM_ENG3,
  	};
  	unsigned cmd;
  	char c[3];
  	int program_size;
  	int nrchars;
  	int offset = 0;
  	int ret;
  	int i;
  
  	/* clear program memory before updating */
  	for (i = 0; i < LP5562_PROGRAM_LENGTH; i++)
  		lp55xx_write(chip, addr[idx] + i, 0);
  
  	i = 0;
  	while ((offset < size - 1) && (i < LP5562_PROGRAM_LENGTH)) {
  		/* separate sscanfs because length is working only for %s */
  		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
  		if (ret != 1)
  			goto err;
  
  		ret = sscanf(c, "%2x", &cmd);
  		if (ret != 1)
  			goto err;
  
  		pattern[i] = (u8)cmd;
  		offset += nrchars;
  		i++;
  	}
  
  	/* Each instruction is 16bit long. Check that length is even */
  	if (i % 2)
  		goto err;
  
  	program_size = i;
  	for (i = 0; i < program_size; i++)
  		lp55xx_write(chip, addr[idx] + i, pattern[i]);
  
  	return 0;
  
  err:
  	dev_err(&chip->cl->dev, "wrong pattern format
  ");
  	return -EINVAL;
  }
  
  static void lp5562_firmware_loaded(struct lp55xx_chip *chip)
  {
  	const struct firmware *fw = chip->fw;

  	/*
  	 * the firmware is encoded in ascii hex character, with 2 chars
  	 * per byte
  	 */
  	if (fw->size > (LP5562_PROGRAM_LENGTH * 2)) {

  		dev_err(&chip->cl->dev, "firmware data size overflow: %zu
  ",
  			fw->size);
  		return;
  	}
  
  	/*

  	 * Program memory sequence

  	 *  1) set engine mode to "LOAD"
  	 *  2) write firmware data into program memory
  	 */
  
  	lp5562_load_engine(chip);
  	lp5562_update_firmware(chip, fw->data, fw->size);
  }
  
  static int lp5562_post_init_device(struct lp55xx_chip *chip)
  {
  	int ret;

  	u8 cfg = LP5562_DEFAULT_CFG;

  
  	/* Set all PWMs to direct control mode */
  	ret = lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
  	if (ret)
  		return ret;
  
  	lp5562_wait_opmode_done();

  	/* Update configuration for the clock setting */
  	if (!lp55xx_is_extclk_used(chip))
  		cfg |= LP5562_CLK_INT;
  
  	ret = lp55xx_write(chip, LP5562_REG_CONFIG, cfg);

  	if (ret)
  		return ret;
  
  	/* Initialize all channels PWM to zero -> leds off */
  	lp55xx_write(chip, LP5562_REG_R_PWM, 0);
  	lp55xx_write(chip, LP5562_REG_G_PWM, 0);
  	lp55xx_write(chip, LP5562_REG_B_PWM, 0);
  	lp55xx_write(chip, LP5562_REG_W_PWM, 0);
  
  	/* Set LED map as register PWM by default */
  	lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
  
  	return 0;
  }

  static int lp5562_led_brightness(struct lp55xx_led *led)

  {

  	struct lp55xx_chip *chip = led->chip;

  	static const u8 addr[] = {

  		LP5562_REG_R_PWM,
  		LP5562_REG_G_PWM,
  		LP5562_REG_B_PWM,
  		LP5562_REG_W_PWM,
  	};

  	int ret;

  
  	mutex_lock(&chip->lock);

  	ret = lp55xx_write(chip, addr[led->chan_nr], led->brightness);

  	mutex_unlock(&chip->lock);

  
  	return ret;

  }
  
  static void lp5562_write_program_memory(struct lp55xx_chip *chip,
  					u8 base, const u8 *rgb, int size)
  {
  	int i;
  
  	if (!rgb || size <= 0)
  		return;
  
  	for (i = 0; i < size; i++)
  		lp55xx_write(chip, base + i, *(rgb + i));
  
  	lp55xx_write(chip, base + i, 0);
  	lp55xx_write(chip, base + i + 1, 0);
  }
  
  /* check the size of program count */
  static inline bool _is_pc_overflow(struct lp55xx_predef_pattern *ptn)
  {

  	return ptn->size_r >= LP5562_PROGRAM_LENGTH ||
  	       ptn->size_g >= LP5562_PROGRAM_LENGTH ||
  	       ptn->size_b >= LP5562_PROGRAM_LENGTH;

  }
  
  static int lp5562_run_predef_led_pattern(struct lp55xx_chip *chip, int mode)
  {
  	struct lp55xx_predef_pattern *ptn;
  	int i;
  
  	if (mode == LP5562_PATTERN_OFF) {
  		lp5562_run_engine(chip, false);
  		return 0;
  	}
  
  	ptn = chip->pdata->patterns + (mode - 1);
  	if (!ptn || _is_pc_overflow(ptn)) {
  		dev_err(&chip->cl->dev, "invalid pattern data
  ");
  		return -EINVAL;
  	}
  
  	lp5562_stop_engine(chip);
  
  	/* Set LED map as RGB */
  	lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_RGB);
  
  	/* Load engines */
  	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
  		chip->engine_idx = i;
  		lp5562_load_engine(chip);
  	}
  
  	/* Clear program registers */
  	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1, 0);
  	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1 + 1, 0);
  	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2, 0);
  	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2 + 1, 0);
  	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3, 0);
  	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3 + 1, 0);
  
  	/* Program engines */
  	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG1,
  				ptn->r, ptn->size_r);
  	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG2,
  				ptn->g, ptn->size_g);
  	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG3,
  				ptn->b, ptn->size_b);
  
  	/* Run engines */
  	lp5562_run_engine(chip, true);
  
  	return 0;
  }
  
  static ssize_t lp5562_store_pattern(struct device *dev,
  				struct device_attribute *attr,
  				const char *buf, size_t len)
  {
  	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
  	struct lp55xx_chip *chip = led->chip;
  	struct lp55xx_predef_pattern *ptn = chip->pdata->patterns;
  	int num_patterns = chip->pdata->num_patterns;
  	unsigned long mode;
  	int ret;
  
  	ret = kstrtoul(buf, 0, &mode);
  	if (ret)
  		return ret;
  
  	if (mode > num_patterns || !ptn)
  		return -EINVAL;
  
  	mutex_lock(&chip->lock);
  	ret = lp5562_run_predef_led_pattern(chip, mode);
  	mutex_unlock(&chip->lock);
  
  	if (ret)
  		return ret;
  
  	return len;
  }
  
  static ssize_t lp5562_store_engine_mux(struct device *dev,
  				     struct device_attribute *attr,
  				     const char *buf, size_t len)
  {
  	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
  	struct lp55xx_chip *chip = led->chip;
  	u8 mask;
  	u8 val;
  
  	/* LED map
  	 * R ... Engine 1 (fixed)
  	 * G ... Engine 2 (fixed)
  	 * B ... Engine 3 (fixed)
  	 * W ... Engine 1 or 2 or 3
  	 */
  
  	if (sysfs_streq(buf, "RGB")) {
  		mask = LP5562_ENG_FOR_RGB_M;
  		val = LP5562_ENG_SEL_RGB;
  	} else if (sysfs_streq(buf, "W")) {
  		enum lp55xx_engine_index idx = chip->engine_idx;
  
  		mask = LP5562_ENG_FOR_W_M;
  		switch (idx) {
  		case LP55XX_ENGINE_1:
  			val = LP5562_ENG1_FOR_W;
  			break;
  		case LP55XX_ENGINE_2:
  			val = LP5562_ENG2_FOR_W;
  			break;
  		case LP55XX_ENGINE_3:
  			val = LP5562_ENG3_FOR_W;
  			break;
  		default:
  			return -EINVAL;
  		}
  
  	} else {
  		dev_err(dev, "choose RGB or W
  ");
  		return -EINVAL;
  	}
  
  	mutex_lock(&chip->lock);
  	lp55xx_update_bits(chip, LP5562_REG_ENG_SEL, mask, val);
  	mutex_unlock(&chip->lock);
  
  	return len;
  }

  static LP55XX_DEV_ATTR_WO(led_pattern, lp5562_store_pattern);
  static LP55XX_DEV_ATTR_WO(engine_mux, lp5562_store_engine_mux);

  
  static struct attribute *lp5562_attributes[] = {
  	&dev_attr_led_pattern.attr,
  	&dev_attr_engine_mux.attr,
  	NULL,
  };
  
  static const struct attribute_group lp5562_group = {
  	.attrs = lp5562_attributes,
  };
  
  /* Chip specific configurations */
  static struct lp55xx_device_config lp5562_cfg = {
  	.max_channel  = LP5562_MAX_LEDS,
  	.reset = {
  		.addr = LP5562_REG_RESET,
  		.val  = LP5562_RESET,
  	},
  	.enable = {
  		.addr = LP5562_REG_ENABLE,
  		.val  = LP5562_ENABLE_DEFAULT,
  	},
  	.post_init_device   = lp5562_post_init_device,
  	.set_led_current    = lp5562_set_led_current,

  	.brightness_fn      = lp5562_led_brightness,

  	.run_engine         = lp5562_run_engine,
  	.firmware_cb        = lp5562_firmware_loaded,
  	.dev_attr_group     = &lp5562_group,
  };
  
  static int lp5562_probe(struct i2c_client *client,
  			const struct i2c_device_id *id)
  {
  	int ret;
  	struct lp55xx_chip *chip;
  	struct lp55xx_led *led;

  	struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);

  	struct device_node *np = dev_of_node(&client->dev);

  	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
  	if (!chip)
  		return -ENOMEM;
  
  	chip->cfg = &lp5562_cfg;

  	if (!pdata) {

  		if (np) {

  			pdata = lp55xx_of_populate_pdata(&client->dev, np,
  							 chip);

  			if (IS_ERR(pdata))
  				return PTR_ERR(pdata);

  		} else {
  			dev_err(&client->dev, "no platform data
  ");
  			return -EINVAL;
  		}

  	}

  	led = devm_kcalloc(&client->dev,
  			pdata->num_channels, sizeof(*led), GFP_KERNEL);

  	if (!led)
  		return -ENOMEM;
  
  	chip->cl = client;
  	chip->pdata = pdata;

  
  	mutex_init(&chip->lock);
  
  	i2c_set_clientdata(client, led);
  
  	ret = lp55xx_init_device(chip);
  	if (ret)
  		goto err_init;
  
  	ret = lp55xx_register_leds(led, chip);
  	if (ret)

  		goto err_out;

  
  	ret = lp55xx_register_sysfs(chip);
  	if (ret) {
  		dev_err(&client->dev, "registering sysfs failed
  ");

  		goto err_out;

  	}
  
  	return 0;

  err_out:

  	lp55xx_deinit_device(chip);
  err_init:
  	return ret;
  }
  
  static int lp5562_remove(struct i2c_client *client)
  {
  	struct lp55xx_led *led = i2c_get_clientdata(client);
  	struct lp55xx_chip *chip = led->chip;
  
  	lp5562_stop_engine(chip);
  
  	lp55xx_unregister_sysfs(chip);

  	lp55xx_deinit_device(chip);
  
  	return 0;
  }
  
  static const struct i2c_device_id lp5562_id[] = {
  	{ "lp5562", 0 },
  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, lp5562_id);

  #ifdef CONFIG_OF
  static const struct of_device_id of_lp5562_leds_match[] = {
  	{ .compatible = "ti,lp5562", },
  	{},
  };
  
  MODULE_DEVICE_TABLE(of, of_lp5562_leds_match);
  #endif

  static struct i2c_driver lp5562_driver = {
  	.driver = {
  		.name	= "lp5562",

  		.of_match_table = of_match_ptr(of_lp5562_leds_match),

  	},
  	.probe		= lp5562_probe,
  	.remove		= lp5562_remove,
  	.id_table	= lp5562_id,
  };
  
  module_i2c_driver(lp5562_driver);
  
  MODULE_DESCRIPTION("Texas Instruments LP5562 LED Driver");
  MODULE_AUTHOR("Milo Kim");
  MODULE_LICENSE("GPL");