drivers/leds/leds-lp5521.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * LP5521 LED chip driver.
  *
  * Copyright (C) 2010 Nokia Corporation
  * Copyright (C) 2012 Texas Instruments
  *
  * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
  *          Milo(Woogyom) Kim <milo.kim@ti.com>
  */

 #include <linux/cleanup.h>
 #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/platform_data/leds-lp55xx.h>
 #include <linux/slab.h>
 #include <linux/of.h>

 #include "leds-lp55xx-common.h"

 #define LP5521_MAX_LEDS			3
 #define LP5521_CMD_DIRECT		0x3F

 /* Registers */
 #define LP5521_REG_ENABLE		0x00
 #define LP5521_REG_OP_MODE		0x01
 #define LP5521_REG_R_PWM		0x02
 #define LP5521_REG_G_PWM		0x03
 #define LP5521_REG_B_PWM		0x04
 #define LP5521_REG_R_CURRENT		0x05
 #define LP5521_REG_G_CURRENT		0x06
 #define LP5521_REG_B_CURRENT		0x07
 #define LP5521_REG_CONFIG		0x08
 #define LP5521_REG_STATUS		0x0C
 #define LP5521_REG_RESET		0x0D
 #define LP5521_REG_R_PROG_MEM		0x10
 #define LP5521_REG_G_PROG_MEM		0x30
 #define LP5521_REG_B_PROG_MEM		0x50

 /* Base register to set LED current */
 #define LP5521_REG_LED_CURRENT_BASE	LP5521_REG_R_CURRENT
 /* Base register to set the brightness */
 #define LP5521_REG_LED_PWM_BASE		LP5521_REG_R_PWM

 /* Bits in ENABLE register */
 #define LP5521_MASTER_ENABLE		0x40	/* Chip master enable */
 #define LP5521_LOGARITHMIC_PWM		0x80	/* Logarithmic PWM adjustment */
 #define LP5521_EXEC_RUN			0x2A
 #define LP5521_ENABLE_DEFAULT	\
 	(LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
 #define LP5521_ENABLE_RUN_PROGRAM	\
 	(LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)

 /* CONFIG register */
 #define LP5521_PWM_HF			0x40	/* PWM: 0 = 256Hz, 1 = 558Hz */
 #define LP5521_PWRSAVE_EN		0x20	/* 1 = Power save mode */
 #define LP5521_CP_MODE_MASK		0x18	/* Charge pump mode */
 #define LP5521_CP_MODE_SHIFT		3
 #define LP5521_R_TO_BATT		0x04	/* R out: 0 = CP, 1 = Vbat */
 #define LP5521_CLK_INT			0x01	/* Internal clock */
 #define LP5521_DEFAULT_CFG		(LP5521_PWM_HF | LP5521_PWRSAVE_EN)

 /* Status */
 #define LP5521_EXT_CLK_USED		0x08

 /* default R channel current register value */
 #define LP5521_REG_R_CURR_DEFAULT	0xAF

 /* Reset register value */
 #define LP5521_RESET			0xFF

 static inline void lp5521_wait_opmode_done(void)
 {
 	/* operation mode change needs to be longer than 153 us */
 	usleep_range(200, 300);
 }

 static inline void lp5521_wait_enable_done(void)
 {
 	/* it takes more 488 us to update ENABLE register */
 	usleep_range(500, 600);
 }

 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
 {
 	int ret;

 	/* stop engine */
 	if (!start) {
 		lp55xx_stop_engine(chip);
 		lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
 		lp5521_wait_opmode_done();
 		return;
 	}

 	ret = lp55xx_run_engine_common(chip);
 	if (!ret)
 		lp5521_wait_enable_done();
 }

 static int lp5521_post_init_device(struct lp55xx_chip *chip)
 {
 	int ret;
 	u8 val;

 	/*
 	 * Make sure that the chip is reset by reading back the r channel
 	 * current reg. This is dummy read is required on some platforms -
 	 * otherwise further access to the R G B channels in the
 	 * LP5521_REG_ENABLE register will not have any effect - strange!
 	 */
 	ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
 	if (ret) {
 		dev_err(&chip->cl->dev, "error in resetting chip\n");
 		return ret;
 	}
 	if (val != LP5521_REG_R_CURR_DEFAULT) {
 		dev_err(&chip->cl->dev,
 			"unexpected data in register (expected 0x%x got 0x%x)\n",
 			LP5521_REG_R_CURR_DEFAULT, val);
 		ret = -EINVAL;
 		return ret;
 	}
 	usleep_range(10000, 20000);

 	/* Set all PWMs to direct control mode */
 	ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
 	if (ret)
 		return ret;

 	/* Update configuration for the clock setting */
 	val = LP5521_DEFAULT_CFG;
 	if (!lp55xx_is_extclk_used(chip))
 		val |= LP5521_CLK_INT;

 	val |= (chip->pdata->charge_pump_mode << LP5521_CP_MODE_SHIFT) & LP5521_CP_MODE_MASK;

 	ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
 	if (ret)
 		return ret;

 	/* Initialize all channels PWM to zero -> leds off */
 	lp55xx_write(chip, LP5521_REG_R_PWM, 0);
 	lp55xx_write(chip, LP5521_REG_G_PWM, 0);
 	lp55xx_write(chip, LP5521_REG_B_PWM, 0);

 	/* Set engines are set to run state when OP_MODE enables engines */
 	ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
 	if (ret)
 		return ret;

 	lp5521_wait_enable_done();

 	return 0;
 }

 static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
 {
 	struct lp55xx_platform_data *pdata = chip->pdata;
 	int ret;
 	u8 status;

 	ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
 	if (ret < 0)
 		return ret;

 	if (pdata->clock_mode != LP55XX_CLOCK_EXT)
 		return 0;

 	/* Check that ext clock is really in use if requested */
 	if  ((status & LP5521_EXT_CLK_USED) == 0)
 		return -EIO;

 	return 0;
 }

 static ssize_t lp5521_selftest(struct device *dev,
 			       struct device_attribute *attr,
 			       char *buf)
 {
 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
 	struct lp55xx_chip *chip = led->chip;
 	int ret;

 	guard(mutex)(&chip->lock);

 	ret = lp5521_run_selftest(chip, buf);

 	return sysfs_emit(buf, "%s\n", ret ? "FAIL" : "OK");
 }

 /* device attributes */
 LP55XX_DEV_ATTR_ENGINE_MODE(1);
 LP55XX_DEV_ATTR_ENGINE_MODE(2);
 LP55XX_DEV_ATTR_ENGINE_MODE(3);
 LP55XX_DEV_ATTR_ENGINE_LOAD(1);
 LP55XX_DEV_ATTR_ENGINE_LOAD(2);
 LP55XX_DEV_ATTR_ENGINE_LOAD(3);
 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);

 static struct attribute *lp5521_attributes[] = {
 	&dev_attr_engine1_mode.attr,
 	&dev_attr_engine2_mode.attr,
 	&dev_attr_engine3_mode.attr,
 	&dev_attr_engine1_load.attr,
 	&dev_attr_engine2_load.attr,
 	&dev_attr_engine3_load.attr,
 	&dev_attr_selftest.attr,
 	NULL
 };

 static const struct attribute_group lp5521_group = {
 	.attrs = lp5521_attributes,
 };

 /* Chip specific configurations */
 static struct lp55xx_device_config lp5521_cfg = {
 	.reg_op_mode = {
 		.addr = LP5521_REG_OP_MODE,
 	},
 	.reg_exec = {
 		.addr = LP5521_REG_ENABLE,
 	},
 	.reset = {
 		.addr = LP5521_REG_RESET,
 		.val  = LP5521_RESET,
 	},
 	.enable = {
 		.addr = LP5521_REG_ENABLE,
 		.val  = LP5521_ENABLE_DEFAULT,
 	},
 	.prog_mem_base = {
 		.addr = LP5521_REG_R_PROG_MEM,
 	},
 	.reg_led_pwm_base = {
 		.addr = LP5521_REG_LED_PWM_BASE,
 	},
 	.reg_led_current_base = {
 		.addr = LP5521_REG_LED_CURRENT_BASE,
 	},
 	.max_channel  = LP5521_MAX_LEDS,
 	.post_init_device   = lp5521_post_init_device,
 	.brightness_fn      = lp55xx_led_brightness,
 	.multicolor_brightness_fn = lp55xx_multicolor_brightness,
 	.set_led_current    = lp55xx_set_led_current,
 	.firmware_cb        = lp55xx_firmware_loaded_cb,
 	.run_engine         = lp5521_run_engine,
 	.dev_attr_group     = &lp5521_group,
 };

 static const struct i2c_device_id lp5521_id[] = {
 	{ "lp5521", .driver_data = (kernel_ulong_t)&lp5521_cfg, }, /* Three channel chip */
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, lp5521_id);

 static const struct of_device_id of_lp5521_leds_match[] = {
 	{ .compatible = "national,lp5521", .data = &lp5521_cfg, },
 	{},
 };

 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);

 static struct i2c_driver lp5521_driver = {
 	.driver = {
 		.name	= "lp5521",
 		.of_match_table = of_lp5521_leds_match,
 	},
 	.probe		= lp55xx_probe,
 	.remove		= lp55xx_remove,
 	.id_table	= lp5521_id,
 };

 module_i2c_driver(lp5521_driver);

 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
 MODULE_DESCRIPTION("LP5521 LED engine");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* LP5521 LED chip driver.
	*
	* Copyright (C) 2010 Nokia Corporation
	* Copyright (C) 2012 Texas Instruments
	*
	* Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
	* Milo(Woogyom) Kim <milo.kim@ti.com>
	*/

	#include <linux/cleanup.h>
	#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/platform_data/leds-lp55xx.h>
	#include <linux/slab.h>
	#include <linux/of.h>

	#include "leds-lp55xx-common.h"

	#define LP5521_MAX_LEDS 3
	#define LP5521_CMD_DIRECT 0x3F

	/* Registers */
	#define LP5521_REG_ENABLE 0x00
	#define LP5521_REG_OP_MODE 0x01
	#define LP5521_REG_R_PWM 0x02
	#define LP5521_REG_G_PWM 0x03
	#define LP5521_REG_B_PWM 0x04
	#define LP5521_REG_R_CURRENT 0x05
	#define LP5521_REG_G_CURRENT 0x06
	#define LP5521_REG_B_CURRENT 0x07
	#define LP5521_REG_CONFIG 0x08
	#define LP5521_REG_STATUS 0x0C
	#define LP5521_REG_RESET 0x0D
	#define LP5521_REG_R_PROG_MEM 0x10
	#define LP5521_REG_G_PROG_MEM 0x30
	#define LP5521_REG_B_PROG_MEM 0x50

	/* Base register to set LED current */
	#define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT
	/* Base register to set the brightness */
	#define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM

	/* Bits in ENABLE register */
	#define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */
	#define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */
	#define LP5521_EXEC_RUN 0x2A
	#define LP5521_ENABLE_DEFAULT \
	(LP5521_MASTER_ENABLE \| LP5521_LOGARITHMIC_PWM)
	#define LP5521_ENABLE_RUN_PROGRAM \
	(LP5521_ENABLE_DEFAULT \| LP5521_EXEC_RUN)

	/* CONFIG register */
	#define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
	#define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
	#define LP5521_CP_MODE_MASK 0x18 /* Charge pump mode */
	#define LP5521_CP_MODE_SHIFT 3
	#define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */
	#define LP5521_CLK_INT 0x01 /* Internal clock */
	#define LP5521_DEFAULT_CFG (LP5521_PWM_HF \| LP5521_PWRSAVE_EN)

	/* Status */
	#define LP5521_EXT_CLK_USED 0x08

	/* default R channel current register value */
	#define LP5521_REG_R_CURR_DEFAULT 0xAF

	/* Reset register value */
	#define LP5521_RESET 0xFF

	static inline void lp5521_wait_opmode_done(void)
	{
	/* operation mode change needs to be longer than 153 us */
	usleep_range(200, 300);
	}

	static inline void lp5521_wait_enable_done(void)
	{
	/* it takes more 488 us to update ENABLE register */
	usleep_range(500, 600);
	}

	static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
	{
	int ret;

	/* stop engine */
	if (!start) {
	lp55xx_stop_engine(chip);
	lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
	lp5521_wait_opmode_done();
	return;
	}

	ret = lp55xx_run_engine_common(chip);
	if (!ret)
	lp5521_wait_enable_done();
	}

	static int lp5521_post_init_device(struct lp55xx_chip *chip)
	{
	int ret;
	u8 val;

	/*
	* Make sure that the chip is reset by reading back the r channel
	* current reg. This is dummy read is required on some platforms -
	* otherwise further access to the R G B channels in the
	* LP5521_REG_ENABLE register will not have any effect - strange!
	*/
	ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
	if (ret) {
	dev_err(&chip->cl->dev, "error in resetting chip\n");
	return ret;
	}
	if (val != LP5521_REG_R_CURR_DEFAULT) {
	dev_err(&chip->cl->dev,
	"unexpected data in register (expected 0x%x got 0x%x)\n",
	LP5521_REG_R_CURR_DEFAULT, val);
	ret = -EINVAL;
	return ret;
	}
	usleep_range(10000, 20000);

	/* Set all PWMs to direct control mode */
	ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
	if (ret)
	return ret;

	/* Update configuration for the clock setting */
	val = LP5521_DEFAULT_CFG;
	if (!lp55xx_is_extclk_used(chip))
	val \|= LP5521_CLK_INT;

	val \|= (chip->pdata->charge_pump_mode << LP5521_CP_MODE_SHIFT) & LP5521_CP_MODE_MASK;

	ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
	if (ret)
	return ret;

	/* Initialize all channels PWM to zero -> leds off */
	lp55xx_write(chip, LP5521_REG_R_PWM, 0);
	lp55xx_write(chip, LP5521_REG_G_PWM, 0);
	lp55xx_write(chip, LP5521_REG_B_PWM, 0);

	/* Set engines are set to run state when OP_MODE enables engines */
	ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
	if (ret)
	return ret;

	lp5521_wait_enable_done();

	return 0;
	}

	static int lp5521_run_selftest(struct lp55xx_chip chip, char buf)
	{
	struct lp55xx_platform_data *pdata = chip->pdata;
	int ret;
	u8 status;

	ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
	if (ret < 0)
	return ret;

	if (pdata->clock_mode != LP55XX_CLOCK_EXT)
	return 0;

	/* Check that ext clock is really in use if requested */
	if ((status & LP5521_EXT_CLK_USED) == 0)
	return -EIO;

	return 0;
	}

	static ssize_t lp5521_selftest(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
	struct lp55xx_chip *chip = led->chip;
	int ret;

	guard(mutex)(&chip->lock);

	ret = lp5521_run_selftest(chip, buf);

	return sysfs_emit(buf, "%s\n", ret ? "FAIL" : "OK");
	}

	/* device attributes */
	LP55XX_DEV_ATTR_ENGINE_MODE(1);
	LP55XX_DEV_ATTR_ENGINE_MODE(2);
	LP55XX_DEV_ATTR_ENGINE_MODE(3);
	LP55XX_DEV_ATTR_ENGINE_LOAD(1);
	LP55XX_DEV_ATTR_ENGINE_LOAD(2);
	LP55XX_DEV_ATTR_ENGINE_LOAD(3);
	static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);

	static struct attribute *lp5521_attributes[] = {
	&dev_attr_engine1_mode.attr,
	&dev_attr_engine2_mode.attr,
	&dev_attr_engine3_mode.attr,
	&dev_attr_engine1_load.attr,
	&dev_attr_engine2_load.attr,
	&dev_attr_engine3_load.attr,
	&dev_attr_selftest.attr,
	NULL
	};

	static const struct attribute_group lp5521_group = {
	.attrs = lp5521_attributes,
	};

	/* Chip specific configurations */
	static struct lp55xx_device_config lp5521_cfg = {
	.reg_op_mode = {
	.addr = LP5521_REG_OP_MODE,
	},
	.reg_exec = {
	.addr = LP5521_REG_ENABLE,
	},
	.reset = {
	.addr = LP5521_REG_RESET,
	.val = LP5521_RESET,
	},
	.enable = {
	.addr = LP5521_REG_ENABLE,
	.val = LP5521_ENABLE_DEFAULT,
	},
	.prog_mem_base = {
	.addr = LP5521_REG_R_PROG_MEM,
	},
	.reg_led_pwm_base = {
	.addr = LP5521_REG_LED_PWM_BASE,
	},
	.reg_led_current_base = {
	.addr = LP5521_REG_LED_CURRENT_BASE,
	},
	.max_channel = LP5521_MAX_LEDS,
	.post_init_device = lp5521_post_init_device,
	.brightness_fn = lp55xx_led_brightness,
	.multicolor_brightness_fn = lp55xx_multicolor_brightness,
	.set_led_current = lp55xx_set_led_current,
	.firmware_cb = lp55xx_firmware_loaded_cb,
	.run_engine = lp5521_run_engine,
	.dev_attr_group = &lp5521_group,
	};

	static const struct i2c_device_id lp5521_id[] = {
	{ "lp5521", .driver_data = (kernel_ulong_t)&lp5521_cfg, }, /* Three channel chip */
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, lp5521_id);

	static const struct of_device_id of_lp5521_leds_match[] = {
	{ .compatible = "national,lp5521", .data = &lp5521_cfg, },
	{},
	};

	MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);

	static struct i2c_driver lp5521_driver = {
	.driver = {
	.name = "lp5521",
	.of_match_table = of_lp5521_leds_match,
	},
	.probe = lp55xx_probe,
	.remove = lp55xx_remove,
	.id_table = lp5521_id,
	};

	module_i2c_driver(lp5521_driver);

	MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
	MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
	MODULE_DESCRIPTION("LP5521 LED engine");
	MODULE_LICENSE("GPL v2");