[linux.git] / drivers / leds / leds-aat1290.c

/*
 *	LED Flash class driver for the AAT1290
 *	1.5A Step-Up Current Regulator for Flash LEDs
 *
 *	Copyright (C) 2015, Samsung Electronics Co., Ltd.
 *	Author: Jacek Anaszewski <[email protected]>
 *
 * 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/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/led-class-flash.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <media/v4l2-flash-led-class.h>

#define AAT1290_MOVIE_MODE_CURRENT_ADDR	17
#define AAT1290_MAX_MM_CURR_PERCENT_0	16
#define AAT1290_MAX_MM_CURR_PERCENT_100	1

#define AAT1290_FLASH_SAFETY_TIMER_ADDR	18

#define AAT1290_MOVIE_MODE_CONFIG_ADDR	19
#define AAT1290_MOVIE_MODE_OFF		1
#define AAT1290_MOVIE_MODE_ON		3

#define AAT1290_MM_CURRENT_RATIO_ADDR	20
#define AAT1290_MM_TO_FL_1_92		1

#define AAT1290_MM_TO_FL_RATIO		1000 / 1920
#define AAT1290_MAX_MM_CURRENT(fl_max)	(fl_max * AAT1290_MM_TO_FL_RATIO)

#define AAT1290_LATCH_TIME_MIN_US	500
#define AAT1290_LATCH_TIME_MAX_US	1000
#define AAT1290_EN_SET_TICK_TIME_US	1
#define AAT1290_FLEN_OFF_DELAY_TIME_US	10
#define AAT1290_FLASH_TM_NUM_LEVELS	16
#define AAT1290_MM_CURRENT_SCALE_SIZE	15


struct aat1290_led_config_data {
	/* maximum LED current in movie mode */
	u32 max_mm_current;
	/* maximum LED current in flash mode */
	u32 max_flash_current;
	/* maximum flash timeout */
	u32 max_flash_tm;
	/* external strobe capability */
	bool has_external_strobe;
	/* max LED brightness level */
	enum led_brightness max_brightness;
};

struct aat1290_led {
	/* platform device data */
	struct platform_device *pdev;
	/* secures access to the device */
	struct mutex lock;

	/* corresponding LED Flash class device */
	struct led_classdev_flash fled_cdev;
	/* V4L2 Flash device */
	struct v4l2_flash *v4l2_flash;

	/* FLEN pin */
	struct gpio_desc *gpio_fl_en;
	/* EN|SET pin  */
	struct gpio_desc *gpio_en_set;
	/* movie mode current scale */
	int *mm_current_scale;
	/* device mode */
	bool movie_mode;

	/* brightness cache */
	unsigned int torch_brightness;
};

static struct aat1290_led *fled_cdev_to_led(
				struct led_classdev_flash *fled_cdev)
{
	return container_of(fled_cdev, struct aat1290_led, fled_cdev);
}

static struct led_classdev_flash *led_cdev_to_fled_cdev(
				struct led_classdev *led_cdev)
{
	return container_of(led_cdev, struct led_classdev_flash, led_cdev);
}

static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value)
{
	int i;

	gpiod_direction_output(led->gpio_fl_en, 0);
	gpiod_direction_output(led->gpio_en_set, 0);

	udelay(AAT1290_FLEN_OFF_DELAY_TIME_US);

	/* write address */
	for (i = 0; i < addr; ++i) {
		udelay(AAT1290_EN_SET_TICK_TIME_US);
		gpiod_direction_output(led->gpio_en_set, 0);
		udelay(AAT1290_EN_SET_TICK_TIME_US);
		gpiod_direction_output(led->gpio_en_set, 1);
	}

	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);

	/* write data */
	for (i = 0; i < value; ++i) {
		udelay(AAT1290_EN_SET_TICK_TIME_US);
		gpiod_direction_output(led->gpio_en_set, 0);
		udelay(AAT1290_EN_SET_TICK_TIME_US);
		gpiod_direction_output(led->gpio_en_set, 1);
	}

	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
}

static void aat1290_set_flash_safety_timer(struct aat1290_led *led,
					unsigned int micro_sec)
{
	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
	struct led_flash_setting *flash_tm = &fled_cdev->timeout;
	int flash_tm_reg = AAT1290_FLASH_TM_NUM_LEVELS -
				(micro_sec / flash_tm->step) + 1;

	aat1290_as2cwire_write(led, AAT1290_FLASH_SAFETY_TIMER_ADDR,
							flash_tm_reg);
}

/* LED subsystem callbacks */

static int aat1290_led_brightness_set(struct led_classdev *led_cdev,
					enum led_brightness brightness)
{
	struct led_classdev_flash *fled_cdev = led_cdev_to_fled_cdev(led_cdev);
	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);

	mutex_lock(&led->lock);

	if (brightness == 0) {
		gpiod_direction_output(led->gpio_fl_en, 0);
		gpiod_direction_output(led->gpio_en_set, 0);
		led->movie_mode = false;
	} else {
		if (!led->movie_mode) {
			aat1290_as2cwire_write(led,
				AAT1290_MM_CURRENT_RATIO_ADDR,
				AAT1290_MM_TO_FL_1_92);
			led->movie_mode = true;
		}

		aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CURRENT_ADDR,
				AAT1290_MAX_MM_CURR_PERCENT_0 - brightness);
		aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR,
				AAT1290_MOVIE_MODE_ON);
	}

	mutex_unlock(&led->lock);

	return 0;
}

static int aat1290_led_flash_strobe_set(struct led_classdev_flash *fled_cdev,
					 bool state)

{
	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
	struct led_flash_setting *timeout = &fled_cdev->timeout;

	mutex_lock(&led->lock);

	if (state) {
		aat1290_set_flash_safety_timer(led, timeout->val);
		gpiod_direction_output(led->gpio_fl_en, 1);
	} else {
		gpiod_direction_output(led->gpio_fl_en, 0);
		gpiod_direction_output(led->gpio_en_set, 0);
	}

	/*
	 * To reenter movie mode after a flash event the part must be cycled
	 * off and back on to reset the movie mode and reprogrammed via the
	 * AS2Cwire. Therefore the brightness and movie_mode properties needs
	 * to be updated here to reflect the actual state.
	 */
	led_cdev->brightness = 0;
	led->movie_mode = false;

	mutex_unlock(&led->lock);

	return 0;
}

static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
						u32 timeout)
{
	/*
	 * Don't do anything - flash timeout is cached in the led-class-flash
	 * core and will be applied in the strobe_set op, as writing the
	 * safety timer register spuriously turns the torch mode on.
	 */

	return 0;
}

static int aat1290_led_parse_dt(struct aat1290_led *led,
			struct aat1290_led_config_data *cfg,
			struct device_node **sub_node)
{
	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
	struct device *dev = &led->pdev->dev;
	struct device_node *child_node;
#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	struct pinctrl *pinctrl;
#endif
	int ret = 0;

	led->gpio_fl_en = devm_gpiod_get(dev, "flen", GPIOD_ASIS);
	if (IS_ERR(led->gpio_fl_en)) {
		ret = PTR_ERR(led->gpio_fl_en);
		dev_err(dev, "Unable to claim gpio \"flen\".\n");
		return ret;
	}

	led->gpio_en_set = devm_gpiod_get(dev, "enset", GPIOD_ASIS);
	if (IS_ERR(led->gpio_en_set)) {
		ret = PTR_ERR(led->gpio_en_set);
		dev_err(dev, "Unable to claim gpio \"enset\".\n");
		return ret;
	}

#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);
	if (IS_ERR(pinctrl)) {
		cfg->has_external_strobe = false;
		dev_info(dev,
			 "No support for external strobe detected.\n");
	} else {
		cfg->has_external_strobe = true;
	}
#endif

	child_node = of_get_next_available_child(dev->of_node, NULL);
	if (!child_node) {
		dev_err(dev, "No DT child node found for connected LED.\n");
		return -EINVAL;
	}

	led_cdev->name = of_get_property(child_node, "label", NULL) ? :
						child_node->name;

	ret = of_property_read_u32(child_node, "led-max-microamp",
				&cfg->max_mm_current);
	/*
	 * led-max-microamp will default to 1/20 of flash-max-microamp
	 * in case it is missing.
	 */
	if (ret < 0)
		dev_warn(dev,
			"led-max-microamp DT property missing\n");

	ret = of_property_read_u32(child_node, "flash-max-microamp",
				&cfg->max_flash_current);
	if (ret < 0) {
		dev_err(dev,
			"flash-max-microamp DT property missing\n");
		goto err_parse_dt;
	}

	ret = of_property_read_u32(child_node, "flash-max-timeout-us",
				&cfg->max_flash_tm);
	if (ret < 0) {
		dev_err(dev,
			"flash-max-timeout-us DT property missing\n");
		goto err_parse_dt;
	}

	*sub_node = child_node;

err_parse_dt:
	of_node_put(child_node);

	return ret;
}

static void aat1290_led_validate_mm_current(struct aat1290_led *led,
					struct aat1290_led_config_data *cfg)
{
	int i, b = 0, e = AAT1290_MM_CURRENT_SCALE_SIZE;

	while (e - b > 1) {
		i = b + (e - b) / 2;
		if (cfg->max_mm_current < led->mm_current_scale[i])
			e = i;
		else
			b = i;
	}

	cfg->max_mm_current = led->mm_current_scale[b];
	cfg->max_brightness = b + 1;
}

static int init_mm_current_scale(struct aat1290_led *led,
			struct aat1290_led_config_data *cfg)
{
	static const int max_mm_current_percent[] = {
		20, 22, 25, 28, 32, 36, 40, 45, 50, 56,
		63, 71, 79, 89, 100
	};
	int i, max_mm_current =
			AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);

	led->mm_current_scale = devm_kzalloc(&led->pdev->dev,
					sizeof(max_mm_current_percent),
					GFP_KERNEL);
	if (!led->mm_current_scale)
		return -ENOMEM;

	for (i = 0; i < AAT1290_MM_CURRENT_SCALE_SIZE; ++i)
		led->mm_current_scale[i] = max_mm_current *
					  max_mm_current_percent[i] / 100;

	return 0;
}

static int aat1290_led_get_configuration(struct aat1290_led *led,
					struct aat1290_led_config_data *cfg,
					struct device_node **sub_node)
{
	int ret;

	ret = aat1290_led_parse_dt(led, cfg, sub_node);
	if (ret < 0)
		return ret;
	/*
	 * Init non-linear movie mode current scale basing
	 * on the max flash current from led configuration.
	 */
	ret = init_mm_current_scale(led, cfg);
	if (ret < 0)
		return ret;

	aat1290_led_validate_mm_current(led, cfg);

#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
#else
	devm_kfree(&led->pdev->dev, led->mm_current_scale);
#endif

	return 0;
}

static void aat1290_init_flash_timeout(struct aat1290_led *led,
				struct aat1290_led_config_data *cfg)
{
	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
	struct led_flash_setting *setting;

	/* Init flash timeout setting */
	setting = &fled_cdev->timeout;
	setting->min = cfg->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS;
	setting->max = cfg->max_flash_tm;
	setting->step = setting->min;
	setting->val = setting->max;
}

#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
static enum led_brightness aat1290_intensity_to_brightness(
					struct v4l2_flash *v4l2_flash,
					s32 intensity)
{
	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
	int i;

	for (i = AAT1290_MM_CURRENT_SCALE_SIZE - 1; i >= 0; --i)
		if (intensity >= led->mm_current_scale[i])
			return i + 1;

	return 1;
}

static s32 aat1290_brightness_to_intensity(struct v4l2_flash *v4l2_flash,
					enum led_brightness brightness)
{
	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);

	return led->mm_current_scale[brightness - 1];
}

static int aat1290_led_external_strobe_set(struct v4l2_flash *v4l2_flash,
						bool enable)
{
	struct aat1290_led *led = fled_cdev_to_led(v4l2_flash->fled_cdev);
	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
	struct pinctrl *pinctrl;

	gpiod_direction_output(led->gpio_fl_en, 0);
	gpiod_direction_output(led->gpio_en_set, 0);

	led->movie_mode = false;
	led_cdev->brightness = 0;

	pinctrl = devm_pinctrl_get_select(&led->pdev->dev,
						enable ? "isp" : "host");
	if (IS_ERR(pinctrl)) {
		dev_warn(&led->pdev->dev, "Unable to switch strobe source.\n");
		return PTR_ERR(pinctrl);
	}

	return 0;
}

static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
					struct aat1290_led_config_data *led_cfg,
					struct v4l2_flash_config *v4l2_sd_cfg)
{
	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
	struct led_flash_setting *s;

	strlcpy(v4l2_sd_cfg->dev_name, led_cdev->name,
		sizeof(v4l2_sd_cfg->dev_name));

	s = &v4l2_sd_cfg->intensity;
	s->min = led->mm_current_scale[0];
	s->max = led_cfg->max_mm_current;
	s->step = 1;
	s->val = s->max;

	v4l2_sd_cfg->has_external_strobe = led_cfg->has_external_strobe;
}

static const struct v4l2_flash_ops v4l2_flash_ops = {
	.external_strobe_set = aat1290_led_external_strobe_set,
	.intensity_to_led_brightness = aat1290_intensity_to_brightness,
	.led_brightness_to_intensity = aat1290_brightness_to_intensity,
};
#else
static inline void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
				struct aat1290_led_config_data *led_cfg,
				struct v4l2_flash_config *v4l2_sd_cfg)
{
}
static const struct v4l2_flash_ops v4l2_flash_ops;
#endif

static const struct led_flash_ops flash_ops = {
	.strobe_set = aat1290_led_flash_strobe_set,
	.timeout_set = aat1290_led_flash_timeout_set,
};

static int aat1290_led_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *sub_node = NULL;
	struct aat1290_led *led;
	struct led_classdev *led_cdev;
	struct led_classdev_flash *fled_cdev;
	struct aat1290_led_config_data led_cfg = {};
	struct v4l2_flash_config v4l2_sd_cfg = {};
	int ret;

	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
	if (!led)
		return -ENOMEM;

	led->pdev = pdev;
	platform_set_drvdata(pdev, led);

	fled_cdev = &led->fled_cdev;
	fled_cdev->ops = &flash_ops;
	led_cdev = &fled_cdev->led_cdev;

	ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);
	if (ret < 0)
		return ret;

	mutex_init(&led->lock);

	/* Initialize LED Flash class device */
	led_cdev->brightness_set_blocking = aat1290_led_brightness_set;
	led_cdev->max_brightness = led_cfg.max_brightness;
	led_cdev->flags |= LED_DEV_CAP_FLASH;

	aat1290_init_flash_timeout(led, &led_cfg);

	/* Register LED Flash class device */
	ret = led_classdev_flash_register(&pdev->dev, fled_cdev);
	if (ret < 0)
		goto err_flash_register;

	aat1290_init_v4l2_flash_config(led, &led_cfg, &v4l2_sd_cfg);

	/* Create V4L2 Flash subdev. */
	led->v4l2_flash = v4l2_flash_init(dev, of_fwnode_handle(sub_node),
					  fled_cdev, &v4l2_flash_ops,
					  &v4l2_sd_cfg);
	if (IS_ERR(led->v4l2_flash)) {
		ret = PTR_ERR(led->v4l2_flash);
		goto error_v4l2_flash_init;
	}

	return 0;

error_v4l2_flash_init:
	led_classdev_flash_unregister(fled_cdev);
err_flash_register:
	mutex_destroy(&led->lock);

	return ret;
}

static int aat1290_led_remove(struct platform_device *pdev)
{
	struct aat1290_led *led = platform_get_drvdata(pdev);

	v4l2_flash_release(led->v4l2_flash);
	led_classdev_flash_unregister(&led->fled_cdev);

	mutex_destroy(&led->lock);

	return 0;
}

static const struct of_device_id aat1290_led_dt_match[] = {
	{ .compatible = "skyworks,aat1290" },
	{},
};
MODULE_DEVICE_TABLE(of, aat1290_led_dt_match);

static struct platform_driver aat1290_led_driver = {
	.probe		= aat1290_led_probe,
	.remove		= aat1290_led_remove,
	.driver		= {
		.name	= "aat1290",
		.of_match_table = aat1290_led_dt_match,
	},
};

module_platform_driver(aat1290_led_driver);

MODULE_AUTHOR("Jacek Anaszewski <[email protected]>");
MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
49c34b8e JA	1	/*
	2	* LED Flash class driver for the AAT1290
	3	* 1.5A Step-Up Current Regulator for Flash LEDs
	4	*
	5	* Copyright (C) 2015, Samsung Electronics Co., Ltd.
	6	* Author: Jacek Anaszewski <[email protected]>
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* version 2 as published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/delay.h>
	14	#include <linux/gpio/consumer.h>
	15	#include <linux/led-class-flash.h>
	16	#include <linux/leds.h>
	17	#include <linux/module.h>
	18	#include <linux/mutex.h>
	19	#include <linux/of.h>
ac69b903	20	#include <linux/pinctrl/consumer.h>
49c34b8e JA	21	#include <linux/platform_device.h>
49c34b8e JA	22	#include <linux/slab.h>
ac69b903	23	#include <media/v4l2-flash-led-class.h>
49c34b8e JA	24
	25	#define AAT1290_MOVIE_MODE_CURRENT_ADDR 17
	26	#define AAT1290_MAX_MM_CURR_PERCENT_0 16
	27	#define AAT1290_MAX_MM_CURR_PERCENT_100 1
	28
	29	#define AAT1290_FLASH_SAFETY_TIMER_ADDR 18
	30
	31	#define AAT1290_MOVIE_MODE_CONFIG_ADDR 19
	32	#define AAT1290_MOVIE_MODE_OFF 1
	33	#define AAT1290_MOVIE_MODE_ON 3
	34
	35	#define AAT1290_MM_CURRENT_RATIO_ADDR 20
	36	#define AAT1290_MM_TO_FL_1_92 1
	37
	38	#define AAT1290_MM_TO_FL_RATIO 1000 / 1920
	39	#define AAT1290_MAX_MM_CURRENT(fl_max) (fl_max * AAT1290_MM_TO_FL_RATIO)
	40
	41	#define AAT1290_LATCH_TIME_MIN_US 500
	42	#define AAT1290_LATCH_TIME_MAX_US 1000
	43	#define AAT1290_EN_SET_TICK_TIME_US 1
	44	#define AAT1290_FLEN_OFF_DELAY_TIME_US 10
	45	#define AAT1290_FLASH_TM_NUM_LEVELS 16
	46	#define AAT1290_MM_CURRENT_SCALE_SIZE 15
	47
	48
	49	struct aat1290_led_config_data {
	50	/* maximum LED current in movie mode */
	51	u32 max_mm_current;
	52	/* maximum LED current in flash mode */
	53	u32 max_flash_current;
	54	/* maximum flash timeout */
	55	u32 max_flash_tm;
ac69b903 JA	56	/* external strobe capability */
ac69b903 JA	57	bool has_external_strobe;
49c34b8e JA	58	/* max LED brightness level */
	59	enum led_brightness max_brightness;
	60	};
	61
	62	struct aat1290_led {
	63	/* platform device data */
	64	struct platform_device *pdev;
	65	/* secures access to the device */
	66	struct mutex lock;
	67
	68	/* corresponding LED Flash class device */
	69	struct led_classdev_flash fled_cdev;
ac69b903 JA	70	/* V4L2 Flash device */
ac69b903 JA	71	struct v4l2_flash *v4l2_flash;
49c34b8e JA	72
	73	/* FLEN pin */
	74	struct gpio_desc *gpio_fl_en;
	75	/* EN\|SET pin */
	76	struct gpio_desc *gpio_en_set;
	77	/* movie mode current scale */
	78	int *mm_current_scale;
	79	/* device mode */
	80	bool movie_mode;
	81
	82	/* brightness cache */
	83	unsigned int torch_brightness;
49c34b8e JA	84	};
	85
	86	static struct aat1290_led *fled_cdev_to_led(
	87	struct led_classdev_flash *fled_cdev)
	88	{
	89	return container_of(fled_cdev, struct aat1290_led, fled_cdev);
	90	}
	91
269e92da JA	92	static struct led_classdev_flash *led_cdev_to_fled_cdev(
	93	struct led_classdev *led_cdev)
	94	{
	95	return container_of(led_cdev, struct led_classdev_flash, led_cdev);
	96	}
	97
49c34b8e JA	98	static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value)
	99	{
	100	int i;
	101
	102	gpiod_direction_output(led->gpio_fl_en, 0);
	103	gpiod_direction_output(led->gpio_en_set, 0);
	104
	105	udelay(AAT1290_FLEN_OFF_DELAY_TIME_US);
	106
	107	/* write address */
	108	for (i = 0; i < addr; ++i) {
	109	udelay(AAT1290_EN_SET_TICK_TIME_US);
	110	gpiod_direction_output(led->gpio_en_set, 0);
	111	udelay(AAT1290_EN_SET_TICK_TIME_US);
	112	gpiod_direction_output(led->gpio_en_set, 1);
	113	}
	114
	115	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
	116
	117	/* write data */
	118	for (i = 0; i < value; ++i) {
	119	udelay(AAT1290_EN_SET_TICK_TIME_US);
	120	gpiod_direction_output(led->gpio_en_set, 0);
	121	udelay(AAT1290_EN_SET_TICK_TIME_US);
	122	gpiod_direction_output(led->gpio_en_set, 1);
	123	}
	124
	125	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
	126	}
	127
	128	static void aat1290_set_flash_safety_timer(struct aat1290_led *led,
	129	unsigned int micro_sec)
	130	{
	131	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
	132	struct led_flash_setting *flash_tm = &fled_cdev->timeout;
	133	int flash_tm_reg = AAT1290_FLASH_TM_NUM_LEVELS -
	134	(micro_sec / flash_tm->step) + 1;
	135
	136	aat1290_as2cwire_write(led, AAT1290_FLASH_SAFETY_TIMER_ADDR,
	137	flash_tm_reg);
	138	}
	139
269e92da JA	140	/* LED subsystem callbacks */
	141
	142	static int aat1290_led_brightness_set(struct led_classdev *led_cdev,
49c34b8e JA	143	enum led_brightness brightness)
49c34b8e JA	144	{
269e92da JA	145	struct led_classdev_flash *fled_cdev = led_cdev_to_fled_cdev(led_cdev);
	146	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
	147
49c34b8e JA	148	mutex_lock(&led->lock);
	149
	150	if (brightness == 0) {
	151	gpiod_direction_output(led->gpio_fl_en, 0);
	152	gpiod_direction_output(led->gpio_en_set, 0);
	153	led->movie_mode = false;
	154	} else {
	155	if (!led->movie_mode) {
	156	aat1290_as2cwire_write(led,
	157	AAT1290_MM_CURRENT_RATIO_ADDR,
	158	AAT1290_MM_TO_FL_1_92);
	159	led->movie_mode = true;
	160	}
	161
	162	aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CURRENT_ADDR,
	163	AAT1290_MAX_MM_CURR_PERCENT_0 - brightness);
	164	aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR,
	165	AAT1290_MOVIE_MODE_ON);
	166	}
	167
	168	mutex_unlock(&led->lock);
49c34b8e JA	169
	170	return 0;
	171	}
	172
	173	static int aat1290_led_flash_strobe_set(struct led_classdev_flash *fled_cdev,
	174	bool state)
	175
	176	{
	177	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
	178	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
	179	struct led_flash_setting *timeout = &fled_cdev->timeout;
	180
	181	mutex_lock(&led->lock);
	182
	183	if (state) {
	184	aat1290_set_flash_safety_timer(led, timeout->val);
	185	gpiod_direction_output(led->gpio_fl_en, 1);
	186	} else {
	187	gpiod_direction_output(led->gpio_fl_en, 0);
	188	gpiod_direction_output(led->gpio_en_set, 0);
	189	}
	190
	191	/*
	192	* To reenter movie mode after a flash event the part must be cycled
	193	* off and back on to reset the movie mode and reprogrammed via the
	194	* AS2Cwire. Therefore the brightness and movie_mode properties needs
	195	* to be updated here to reflect the actual state.
	196	*/
	197	led_cdev->brightness = 0;
	198	led->movie_mode = false;
	199
	200	mutex_unlock(&led->lock);
	201
	202	return 0;
	203	}
	204
	205	static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
	206	u32 timeout)
	207	{
	208	/*
	209	* Don't do anything - flash timeout is cached in the led-class-flash
	210	* core and will be applied in the strobe_set op, as writing the
	211	* safety timer register spuriously turns the torch mode on.
	212	*/
	213
	214	return 0;
	215	}
	216
	217	static int aat1290_led_parse_dt(struct aat1290_led *led,
ac69b903 JA	218	struct aat1290_led_config_data *cfg,
ac69b903 JA	219	struct device_node **sub_node)
49c34b8e JA	220	{
	221	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
	222	struct device *dev = &led->pdev->dev;
	223	struct device_node *child_node;
ac69b903 JA	224	#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	225	struct pinctrl *pinctrl;
	226	#endif
49c34b8e JA	227	int ret = 0;
49c34b8e JA	228
8a687719	229	led->gpio_fl_en = devm_gpiod_get(dev, "flen", GPIOD_ASIS);
49c34b8e JA	230	if (IS_ERR(led->gpio_fl_en)) {
	231	ret = PTR_ERR(led->gpio_fl_en);
	232	dev_err(dev, "Unable to claim gpio \"flen\".\n");
	233	return ret;
	234	}
	235
8a687719	236	led->gpio_en_set = devm_gpiod_get(dev, "enset", GPIOD_ASIS);
49c34b8e JA	237	if (IS_ERR(led->gpio_en_set)) {
	238	ret = PTR_ERR(led->gpio_en_set);
	239	dev_err(dev, "Unable to claim gpio \"enset\".\n");
	240	return ret;
	241	}
	242
ac69b903 JA	243	#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	244	pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);
	245	if (IS_ERR(pinctrl)) {
	246	cfg->has_external_strobe = false;
	247	dev_info(dev,
	248	"No support for external strobe detected.\n");
	249	} else {
	250	cfg->has_external_strobe = true;
	251	}
	252	#endif
	253
49c34b8e JA	254	child_node = of_get_next_available_child(dev->of_node, NULL);
	255	if (!child_node) {
	256	dev_err(dev, "No DT child node found for connected LED.\n");
	257	return -EINVAL;
	258	}
	259
	260	led_cdev->name = of_get_property(child_node, "label", NULL) ? :
	261	child_node->name;
	262
	263	ret = of_property_read_u32(child_node, "led-max-microamp",
	264	&cfg->max_mm_current);
	265	/*
	266	* led-max-microamp will default to 1/20 of flash-max-microamp
	267	* in case it is missing.
	268	*/
	269	if (ret < 0)
	270	dev_warn(dev,
	271	"led-max-microamp DT property missing\n");
	272
	273	ret = of_property_read_u32(child_node, "flash-max-microamp",
	274	&cfg->max_flash_current);
	275	if (ret < 0) {
	276	dev_err(dev,
	277	"flash-max-microamp DT property missing\n");
0c24199c	278	goto err_parse_dt;
49c34b8e JA	279	}
	280
	281	ret = of_property_read_u32(child_node, "flash-max-timeout-us",
	282	&cfg->max_flash_tm);
	283	if (ret < 0) {
	284	dev_err(dev,
	285	"flash-max-timeout-us DT property missing\n");
0c24199c	286	goto err_parse_dt;
49c34b8e JA	287	}
49c34b8e JA	288
ac69b903 JA	289	*sub_node = child_node;
ac69b903 JA	290
0c24199c JA	291	err_parse_dt:
	292	of_node_put(child_node);
	293
49c34b8e JA	294	return ret;
	295	}
	296
	297	static void aat1290_led_validate_mm_current(struct aat1290_led *led,
	298	struct aat1290_led_config_data *cfg)
	299	{
	300	int i, b = 0, e = AAT1290_MM_CURRENT_SCALE_SIZE;
	301
	302	while (e - b > 1) {
	303	i = b + (e - b) / 2;
	304	if (cfg->max_mm_current < led->mm_current_scale[i])
	305	e = i;
	306	else
	307	b = i;
	308	}
	309
	310	cfg->max_mm_current = led->mm_current_scale[b];
	311	cfg->max_brightness = b + 1;
	312	}
	313
305c324f	314	static int init_mm_current_scale(struct aat1290_led *led,
49c34b8e JA	315	struct aat1290_led_config_data *cfg)
49c34b8e JA	316	{
17224244 CIK	317	static const int max_mm_current_percent[] = {
	318	20, 22, 25, 28, 32, 36, 40, 45, 50, 56,
	319	63, 71, 79, 89, 100
	320	};
49c34b8e JA	321	int i, max_mm_current =
	322	AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
	323
ac69b903 JA	324	led->mm_current_scale = devm_kzalloc(&led->pdev->dev,
ac69b903 JA	325	sizeof(max_mm_current_percent),
49c34b8e JA	326	GFP_KERNEL);
	327	if (!led->mm_current_scale)
	328	return -ENOMEM;
	329
	330	for (i = 0; i < AAT1290_MM_CURRENT_SCALE_SIZE; ++i)
	331	led->mm_current_scale[i] = max_mm_current *
	332	max_mm_current_percent[i] / 100;
	333
	334	return 0;
	335	}
	336
	337	static int aat1290_led_get_configuration(struct aat1290_led *led,
ac69b903 JA	338	struct aat1290_led_config_data *cfg,
ac69b903 JA	339	struct device_node **sub_node)
49c34b8e JA	340	{
	341	int ret;
	342
ac69b903	343	ret = aat1290_led_parse_dt(led, cfg, sub_node);
49c34b8e JA	344	if (ret < 0)
	345	return ret;
	346	/*
	347	* Init non-linear movie mode current scale basing
	348	* on the max flash current from led configuration.
	349	*/
	350	ret = init_mm_current_scale(led, cfg);
	351	if (ret < 0)
	352	return ret;
	353
	354	aat1290_led_validate_mm_current(led, cfg);
	355
ac69b903 JA	356	#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	357	#else
	358	devm_kfree(&led->pdev->dev, led->mm_current_scale);
	359	#endif
49c34b8e JA	360
	361	return 0;
	362	}
	363
	364	static void aat1290_init_flash_timeout(struct aat1290_led *led,
	365	struct aat1290_led_config_data *cfg)
	366	{
	367	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
	368	struct led_flash_setting *setting;
	369
	370	/* Init flash timeout setting */
	371	setting = &fled_cdev->timeout;
	372	setting->min = cfg->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS;
	373	setting->max = cfg->max_flash_tm;
	374	setting->step = setting->min;
	375	setting->val = setting->max;
	376	}
	377
ac69b903 JA	378	#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	379	static enum led_brightness aat1290_intensity_to_brightness(
	380	struct v4l2_flash *v4l2_flash,
	381	s32 intensity)
	382	{
	383	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	384	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
	385	int i;
	386
	387	for (i = AAT1290_MM_CURRENT_SCALE_SIZE - 1; i >= 0; --i)
	388	if (intensity >= led->mm_current_scale[i])
	389	return i + 1;
	390
	391	return 1;
	392	}
	393
	394	static s32 aat1290_brightness_to_intensity(struct v4l2_flash *v4l2_flash,
	395	enum led_brightness brightness)
	396	{
	397	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	398	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
	399
	400	return led->mm_current_scale[brightness - 1];
	401	}
	402
	403	static int aat1290_led_external_strobe_set(struct v4l2_flash *v4l2_flash,
	404	bool enable)
	405	{
	406	struct aat1290_led *led = fled_cdev_to_led(v4l2_flash->fled_cdev);
	407	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	408	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
	409	struct pinctrl *pinctrl;
	410
	411	gpiod_direction_output(led->gpio_fl_en, 0);
	412	gpiod_direction_output(led->gpio_en_set, 0);
	413
	414	led->movie_mode = false;
	415	led_cdev->brightness = 0;
	416
	417	pinctrl = devm_pinctrl_get_select(&led->pdev->dev,
	418	enable ? "isp" : "host");
	419	if (IS_ERR(pinctrl)) {
	420	dev_warn(&led->pdev->dev, "Unable to switch strobe source.\n");
	421	return PTR_ERR(pinctrl);
	422	}
	423
	424	return 0;
	425	}
	426
	427	static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
	428	struct aat1290_led_config_data *led_cfg,
	429	struct v4l2_flash_config *v4l2_sd_cfg)
	430	{
	431	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
	432	struct led_flash_setting *s;
	433
	434	strlcpy(v4l2_sd_cfg->dev_name, led_cdev->name,
	435	sizeof(v4l2_sd_cfg->dev_name));
	436
503dd28a	437	s = &v4l2_sd_cfg->intensity;
ac69b903 JA	438	s->min = led->mm_current_scale[0];
	439	s->max = led_cfg->max_mm_current;
	440	s->step = 1;
	441	s->val = s->max;
	442
	443	v4l2_sd_cfg->has_external_strobe = led_cfg->has_external_strobe;
	444	}
	445
	446	static const struct v4l2_flash_ops v4l2_flash_ops = {
	447	.external_strobe_set = aat1290_led_external_strobe_set,
	448	.intensity_to_led_brightness = aat1290_intensity_to_brightness,
	449	.led_brightness_to_intensity = aat1290_brightness_to_intensity,
	450	};
	451	#else
	452	static inline void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
	453	struct aat1290_led_config_data *led_cfg,
	454	struct v4l2_flash_config *v4l2_sd_cfg)
	455	{
	456	}
	457	static const struct v4l2_flash_ops v4l2_flash_ops;
	458	#endif
	459
49c34b8e JA	460	static const struct led_flash_ops flash_ops = {
	461	.strobe_set = aat1290_led_flash_strobe_set,
	462	.timeout_set = aat1290_led_flash_timeout_set,
	463	};
	464
	465	static int aat1290_led_probe(struct platform_device *pdev)
	466	{
	467	struct device *dev = &pdev->dev;
ac69b903	468	struct device_node *sub_node = NULL;
49c34b8e JA	469	struct aat1290_led *led;
	470	struct led_classdev *led_cdev;
	471	struct led_classdev_flash *fled_cdev;
	472	struct aat1290_led_config_data led_cfg = {};
ac69b903	473	struct v4l2_flash_config v4l2_sd_cfg = {};
49c34b8e JA	474	int ret;
	475
	476	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
	477	if (!led)
	478	return -ENOMEM;
	479
	480	led->pdev = pdev;
	481	platform_set_drvdata(pdev, led);
	482
	483	fled_cdev = &led->fled_cdev;
	484	fled_cdev->ops = &flash_ops;
	485	led_cdev = &fled_cdev->led_cdev;
	486
ac69b903	487	ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);
49c34b8e JA	488	if (ret < 0)
	489	return ret;
	490
	491	mutex_init(&led->lock);
	492
	493	/* Initialize LED Flash class device */
269e92da	494	led_cdev->brightness_set_blocking = aat1290_led_brightness_set;
49c34b8e JA	495	led_cdev->max_brightness = led_cfg.max_brightness;
49c34b8e JA	496	led_cdev->flags \|= LED_DEV_CAP_FLASH;
49c34b8e JA	497
	498	aat1290_init_flash_timeout(led, &led_cfg);
	499
	500	/* Register LED Flash class device */
	501	ret = led_classdev_flash_register(&pdev->dev, fled_cdev);
	502	if (ret < 0)
	503	goto err_flash_register;
	504
ac69b903 JA	505	aat1290_init_v4l2_flash_config(led, &led_cfg, &v4l2_sd_cfg);
	506
	507	/* Create V4L2 Flash subdev. */
048ea05b	508	led->v4l2_flash = v4l2_flash_init(dev, of_fwnode_handle(sub_node),
503dd28a	509	fled_cdev, &v4l2_flash_ops,
048ea05b	510	&v4l2_sd_cfg);
ac69b903 JA	511	if (IS_ERR(led->v4l2_flash)) {
	512	ret = PTR_ERR(led->v4l2_flash);
	513	goto error_v4l2_flash_init;
	514	}
	515
49c34b8e JA	516	return 0;
49c34b8e JA	517
ac69b903 JA	518	error_v4l2_flash_init:
ac69b903 JA	519	led_classdev_flash_unregister(fled_cdev);
49c34b8e JA	520	err_flash_register:
	521	mutex_destroy(&led->lock);
	522
	523	return ret;
	524	}
	525
	526	static int aat1290_led_remove(struct platform_device *pdev)
	527	{
	528	struct aat1290_led *led = platform_get_drvdata(pdev);
	529
ac69b903	530	v4l2_flash_release(led->v4l2_flash);
49c34b8e	531	led_classdev_flash_unregister(&led->fled_cdev);
49c34b8e JA	532
	533	mutex_destroy(&led->lock);
	534
	535	return 0;
	536	}
	537
	538	static const struct of_device_id aat1290_led_dt_match[] = {
	539	{ .compatible = "skyworks,aat1290" },
	540	{},
	541	};
93a51aa4	542	MODULE_DEVICE_TABLE(of, aat1290_led_dt_match);
49c34b8e JA	543
	544	static struct platform_driver aat1290_led_driver = {
	545	.probe = aat1290_led_probe,
	546	.remove = aat1290_led_remove,
	547	.driver = {
	548	.name = "aat1290",
	549	.of_match_table = aat1290_led_dt_match,
	550	},
	551	};
	552
	553	module_platform_driver(aat1290_led_driver);
	554
	555	MODULE_AUTHOR("Jacek Anaszewski <[email protected]>");
	556	MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs");
	557	MODULE_LICENSE("GPL v2");