[linux-2.6-block.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 <j.anaszewski@samsung.com>
 *
 * 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 <linux/workqueue.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;
	/* assures led-triggers compatibility */
	struct work_struct work_brightness_set;
};

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 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);
}

static void aat1290_brightness_set(struct aat1290_led *led,
					enum led_brightness brightness)
{
	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);
}

/* LED subsystem callbacks */

static void aat1290_brightness_set_work(struct work_struct *work)
{
	struct aat1290_led *led =
		container_of(work, struct aat1290_led, work_brightness_set);

	aat1290_brightness_set(led, led->torch_brightness);
}

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

	led->torch_brightness = brightness;
	schedule_work(&led->work_brightness_set);
}

static int aat1290_led_brightness_set_sync(struct led_classdev *led_cdev,
					enum led_brightness brightness)
{
	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);

	aat1290_brightness_set(led, brightness);

	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");
		return ret;
	}

	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");
		return ret;
	}

	of_node_put(child_node);

	*sub_node = 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)
{
	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->torch_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 = aat1290_led_brightness_set;
	led_cdev->brightness_set_sync = aat1290_led_brightness_set_sync;
	led_cdev->max_brightness = led_cfg.max_brightness;
	led_cdev->flags |= LED_DEV_CAP_FLASH;
	INIT_WORK(&led->work_brightness_set, aat1290_brightness_set_work);

	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, sub_node, fled_cdev, NULL,
					  &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);
	cancel_work_sync(&led->work_brightness_set);

	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 <j.anaszewski@samsung.com>");
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 <j.anaszewski@samsung.com>
	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>
	22	#include <linux/slab.h>
	23	#include <linux/workqueue.h>
ac69b903	24	#include <media/v4l2-flash-led-class.h>
49c34b8e JA	25
	26	#define AAT1290_MOVIE_MODE_CURRENT_ADDR 17
	27	#define AAT1290_MAX_MM_CURR_PERCENT_0 16
	28	#define AAT1290_MAX_MM_CURR_PERCENT_100 1
	29
	30	#define AAT1290_FLASH_SAFETY_TIMER_ADDR 18
	31
	32	#define AAT1290_MOVIE_MODE_CONFIG_ADDR 19
	33	#define AAT1290_MOVIE_MODE_OFF 1
	34	#define AAT1290_MOVIE_MODE_ON 3
	35
	36	#define AAT1290_MM_CURRENT_RATIO_ADDR 20
	37	#define AAT1290_MM_TO_FL_1_92 1
	38
	39	#define AAT1290_MM_TO_FL_RATIO 1000 / 1920
	40	#define AAT1290_MAX_MM_CURRENT(fl_max) (fl_max * AAT1290_MM_TO_FL_RATIO)
	41
	42	#define AAT1290_LATCH_TIME_MIN_US 500
	43	#define AAT1290_LATCH_TIME_MAX_US 1000
	44	#define AAT1290_EN_SET_TICK_TIME_US 1
	45	#define AAT1290_FLEN_OFF_DELAY_TIME_US 10
	46	#define AAT1290_FLASH_TM_NUM_LEVELS 16
	47	#define AAT1290_MM_CURRENT_SCALE_SIZE 15
	48
	49
	50	struct aat1290_led_config_data {
	51	/* maximum LED current in movie mode */
	52	u32 max_mm_current;
	53	/* maximum LED current in flash mode */
	54	u32 max_flash_current;
	55	/* maximum flash timeout */
	56	u32 max_flash_tm;
ac69b903 JA	57	/* external strobe capability */
ac69b903 JA	58	bool has_external_strobe;
49c34b8e JA	59	/* max LED brightness level */
	60	enum led_brightness max_brightness;
	61	};
	62
	63	struct aat1290_led {
	64	/* platform device data */
	65	struct platform_device *pdev;
	66	/* secures access to the device */
	67	struct mutex lock;
	68
	69	/* corresponding LED Flash class device */
	70	struct led_classdev_flash fled_cdev;
ac69b903 JA	71	/* V4L2 Flash device */
ac69b903 JA	72	struct v4l2_flash *v4l2_flash;
49c34b8e JA	73
	74	/* FLEN pin */
	75	struct gpio_desc *gpio_fl_en;
	76	/* EN\|SET pin */
	77	struct gpio_desc *gpio_en_set;
	78	/* movie mode current scale */
	79	int *mm_current_scale;
	80	/* device mode */
	81	bool movie_mode;
	82
	83	/* brightness cache */
	84	unsigned int torch_brightness;
	85	/* assures led-triggers compatibility */
	86	struct work_struct work_brightness_set;
	87	};
	88
	89	static struct aat1290_led *fled_cdev_to_led(
	90	struct led_classdev_flash *fled_cdev)
	91	{
	92	return container_of(fled_cdev, struct aat1290_led, fled_cdev);
	93	}
	94
	95	static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value)
	96	{
	97	int i;
	98
	99	gpiod_direction_output(led->gpio_fl_en, 0);
	100	gpiod_direction_output(led->gpio_en_set, 0);
	101
	102	udelay(AAT1290_FLEN_OFF_DELAY_TIME_US);
	103
	104	/* write address */
	105	for (i = 0; i < addr; ++i) {
	106	udelay(AAT1290_EN_SET_TICK_TIME_US);
	107	gpiod_direction_output(led->gpio_en_set, 0);
	108	udelay(AAT1290_EN_SET_TICK_TIME_US);
	109	gpiod_direction_output(led->gpio_en_set, 1);
	110	}
	111
	112	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
	113
	114	/* write data */
	115	for (i = 0; i < value; ++i) {
	116	udelay(AAT1290_EN_SET_TICK_TIME_US);
	117	gpiod_direction_output(led->gpio_en_set, 0);
	118	udelay(AAT1290_EN_SET_TICK_TIME_US);
	119	gpiod_direction_output(led->gpio_en_set, 1);
	120	}
	121
	122	usleep_range(AAT1290_LATCH_TIME_MIN_US, AAT1290_LATCH_TIME_MAX_US);
	123	}
	124
	125	static void aat1290_set_flash_safety_timer(struct aat1290_led *led,
	126	unsigned int micro_sec)
	127	{
	128	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
	129	struct led_flash_setting *flash_tm = &fled_cdev->timeout;
	130	int flash_tm_reg = AAT1290_FLASH_TM_NUM_LEVELS -
	131	(micro_sec / flash_tm->step) + 1;
	132
	133	aat1290_as2cwire_write(led, AAT1290_FLASH_SAFETY_TIMER_ADDR,
	134	flash_tm_reg);
	135	}
	136
137	static void aat1290_brightness_set(struct aat1290_led *led,
138	enum led_brightness brightness)
139	{
140	mutex_lock(&led->lock);
141
142	if (brightness == 0) {
143	gpiod_direction_output(led->gpio_fl_en, 0);
144	gpiod_direction_output(led->gpio_en_set, 0);
145	led->movie_mode = false;
146	} else {
147	if (!led->movie_mode) {
148	aat1290_as2cwire_write(led,
149	AAT1290_MM_CURRENT_RATIO_ADDR,
150	AAT1290_MM_TO_FL_1_92);
151	led->movie_mode = true;
152	}
153
154	aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CURRENT_ADDR,
155	AAT1290_MAX_MM_CURR_PERCENT_0 - brightness);
156	aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR,
157	AAT1290_MOVIE_MODE_ON);
158	}
159
160	mutex_unlock(&led->lock);
161	}
162
163	/* LED subsystem callbacks */
164
165	static void aat1290_brightness_set_work(struct work_struct *work)
166	{
167	struct aat1290_led *led =
168	container_of(work, struct aat1290_led, work_brightness_set);
169
170	aat1290_brightness_set(led, led->torch_brightness);
171	}
172
173	static void aat1290_led_brightness_set(struct led_classdev *led_cdev,
174	enum led_brightness brightness)
175	{
176	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
177	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
178
179	led->torch_brightness = brightness;
180	schedule_work(&led->work_brightness_set);
181	}
182
183	static int aat1290_led_brightness_set_sync(struct led_classdev *led_cdev,
184	enum led_brightness brightness)
185	{
186	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
187	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
188
189	aat1290_brightness_set(led, brightness);
190
191	return 0;
192	}
193
194	static int aat1290_led_flash_strobe_set(struct led_classdev_flash *fled_cdev,
195	bool state)
196
197	{
198	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
199	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
200	struct led_flash_setting *timeout = &fled_cdev->timeout;
201
202	mutex_lock(&led->lock);
203
204	if (state) {
205	aat1290_set_flash_safety_timer(led, timeout->val);
206	gpiod_direction_output(led->gpio_fl_en, 1);
207	} else {
208	gpiod_direction_output(led->gpio_fl_en, 0);
209	gpiod_direction_output(led->gpio_en_set, 0);
210	}
211
212	/*
213	* To reenter movie mode after a flash event the part must be cycled
214	* off and back on to reset the movie mode and reprogrammed via the
215	* AS2Cwire. Therefore the brightness and movie_mode properties needs
216	* to be updated here to reflect the actual state.
217	*/
218	led_cdev->brightness = 0;
219	led->movie_mode = false;
220
221	mutex_unlock(&led->lock);
222
223	return 0;
224	}
225
226	static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
227	u32 timeout)
228	{
229	/*
230	* Don't do anything - flash timeout is cached in the led-class-flash
231	* core and will be applied in the strobe_set op, as writing the
232	* safety timer register spuriously turns the torch mode on.
233	*/
234
235	return 0;
236	}
237
238	static int aat1290_led_parse_dt(struct aat1290_led *led,
ac69b903 JA	239	struct aat1290_led_config_data *cfg,
ac69b903 JA	240	struct device_node **sub_node)
49c34b8e JA	241	{
	242	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
	243	struct device *dev = &led->pdev->dev;
	244	struct device_node *child_node;
ac69b903 JA	245	#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	246	struct pinctrl *pinctrl;
	247	#endif
49c34b8e JA	248	int ret = 0;
49c34b8e JA	249
8a687719	250	led->gpio_fl_en = devm_gpiod_get(dev, "flen", GPIOD_ASIS);
49c34b8e JA	251	if (IS_ERR(led->gpio_fl_en)) {
	252	ret = PTR_ERR(led->gpio_fl_en);
	253	dev_err(dev, "Unable to claim gpio \"flen\".\n");
	254	return ret;
	255	}
	256
8a687719	257	led->gpio_en_set = devm_gpiod_get(dev, "enset", GPIOD_ASIS);
49c34b8e JA	258	if (IS_ERR(led->gpio_en_set)) {
	259	ret = PTR_ERR(led->gpio_en_set);
	260	dev_err(dev, "Unable to claim gpio \"enset\".\n");
	261	return ret;
	262	}
	263
ac69b903 JA	264	#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	265	pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);
	266	if (IS_ERR(pinctrl)) {
	267	cfg->has_external_strobe = false;
	268	dev_info(dev,
	269	"No support for external strobe detected.\n");
	270	} else {
	271	cfg->has_external_strobe = true;
	272	}
	273	#endif
	274
49c34b8e JA	275	child_node = of_get_next_available_child(dev->of_node, NULL);
	276	if (!child_node) {
	277	dev_err(dev, "No DT child node found for connected LED.\n");
	278	return -EINVAL;
	279	}
	280
	281	led_cdev->name = of_get_property(child_node, "label", NULL) ? :
	282	child_node->name;
	283
	284	ret = of_property_read_u32(child_node, "led-max-microamp",
	285	&cfg->max_mm_current);
	286	/*
	287	* led-max-microamp will default to 1/20 of flash-max-microamp
	288	* in case it is missing.
	289	*/
	290	if (ret < 0)
	291	dev_warn(dev,
	292	"led-max-microamp DT property missing\n");
	293
	294	ret = of_property_read_u32(child_node, "flash-max-microamp",
	295	&cfg->max_flash_current);
	296	if (ret < 0) {
	297	dev_err(dev,
	298	"flash-max-microamp DT property missing\n");
	299	return ret;
	300	}
	301
	302	ret = of_property_read_u32(child_node, "flash-max-timeout-us",
	303	&cfg->max_flash_tm);
	304	if (ret < 0) {
	305	dev_err(dev,
	306	"flash-max-timeout-us DT property missing\n");
	307	return ret;
	308	}
	309
	310	of_node_put(child_node);
	311
ac69b903 JA	312	*sub_node = child_node;
ac69b903 JA	313
49c34b8e JA	314	return ret;
	315	}
	316
	317	static void aat1290_led_validate_mm_current(struct aat1290_led *led,
	318	struct aat1290_led_config_data *cfg)
	319	{
	320	int i, b = 0, e = AAT1290_MM_CURRENT_SCALE_SIZE;
	321
	322	while (e - b > 1) {
	323	i = b + (e - b) / 2;
	324	if (cfg->max_mm_current < led->mm_current_scale[i])
	325	e = i;
	326	else
	327	b = i;
	328	}
	329
	330	cfg->max_mm_current = led->mm_current_scale[b];
	331	cfg->max_brightness = b + 1;
	332	}
	333
305c324f	334	static int init_mm_current_scale(struct aat1290_led *led,
49c34b8e JA	335	struct aat1290_led_config_data *cfg)
	336	{
	337	int max_mm_current_percent[] = { 20, 22, 25, 28, 32, 36, 40, 45, 50, 56,
	338	63, 71, 79, 89, 100 };
	339	int i, max_mm_current =
	340	AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);
	341
ac69b903 JA	342	led->mm_current_scale = devm_kzalloc(&led->pdev->dev,
ac69b903 JA	343	sizeof(max_mm_current_percent),
49c34b8e JA	344	GFP_KERNEL);
	345	if (!led->mm_current_scale)
	346	return -ENOMEM;
	347
	348	for (i = 0; i < AAT1290_MM_CURRENT_SCALE_SIZE; ++i)
	349	led->mm_current_scale[i] = max_mm_current *
	350	max_mm_current_percent[i] / 100;
	351
	352	return 0;
	353	}
	354
	355	static int aat1290_led_get_configuration(struct aat1290_led *led,
ac69b903 JA	356	struct aat1290_led_config_data *cfg,
ac69b903 JA	357	struct device_node **sub_node)
49c34b8e JA	358	{
	359	int ret;
	360
ac69b903	361	ret = aat1290_led_parse_dt(led, cfg, sub_node);
49c34b8e JA	362	if (ret < 0)
	363	return ret;
	364	/*
	365	* Init non-linear movie mode current scale basing
	366	* on the max flash current from led configuration.
	367	*/
	368	ret = init_mm_current_scale(led, cfg);
	369	if (ret < 0)
	370	return ret;
	371
	372	aat1290_led_validate_mm_current(led, cfg);
	373
ac69b903 JA	374	#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	375	#else
	376	devm_kfree(&led->pdev->dev, led->mm_current_scale);
	377	#endif
49c34b8e JA	378
	379	return 0;
	380	}
	381
	382	static void aat1290_init_flash_timeout(struct aat1290_led *led,
	383	struct aat1290_led_config_data *cfg)
	384	{
	385	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
	386	struct led_flash_setting *setting;
	387
	388	/* Init flash timeout setting */
	389	setting = &fled_cdev->timeout;
	390	setting->min = cfg->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS;
	391	setting->max = cfg->max_flash_tm;
	392	setting->step = setting->min;
	393	setting->val = setting->max;
	394	}
	395
ac69b903 JA	396	#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
	397	static enum led_brightness aat1290_intensity_to_brightness(
	398	struct v4l2_flash *v4l2_flash,
	399	s32 intensity)
	400	{
	401	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	402	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
	403	int i;
	404
	405	for (i = AAT1290_MM_CURRENT_SCALE_SIZE - 1; i >= 0; --i)
	406	if (intensity >= led->mm_current_scale[i])
	407	return i + 1;
	408
	409	return 1;
	410	}
	411
	412	static s32 aat1290_brightness_to_intensity(struct v4l2_flash *v4l2_flash,
	413	enum led_brightness brightness)
	414	{
	415	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	416	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);
	417
	418	return led->mm_current_scale[brightness - 1];
	419	}
	420
	421	static int aat1290_led_external_strobe_set(struct v4l2_flash *v4l2_flash,
	422	bool enable)
	423	{
	424	struct aat1290_led *led = fled_cdev_to_led(v4l2_flash->fled_cdev);
	425	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
	426	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
	427	struct pinctrl *pinctrl;
	428
	429	gpiod_direction_output(led->gpio_fl_en, 0);
	430	gpiod_direction_output(led->gpio_en_set, 0);
	431
	432	led->movie_mode = false;
	433	led_cdev->brightness = 0;
	434
	435	pinctrl = devm_pinctrl_get_select(&led->pdev->dev,
	436	enable ? "isp" : "host");
	437	if (IS_ERR(pinctrl)) {
	438	dev_warn(&led->pdev->dev, "Unable to switch strobe source.\n");
	439	return PTR_ERR(pinctrl);
	440	}
	441
	442	return 0;
	443	}
	444
	445	static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
	446	struct aat1290_led_config_data *led_cfg,
	447	struct v4l2_flash_config *v4l2_sd_cfg)
	448	{
	449	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;
	450	struct led_flash_setting *s;
	451
	452	strlcpy(v4l2_sd_cfg->dev_name, led_cdev->name,
	453	sizeof(v4l2_sd_cfg->dev_name));
	454
	455	s = &v4l2_sd_cfg->torch_intensity;
	456	s->min = led->mm_current_scale[0];
	457	s->max = led_cfg->max_mm_current;
	458	s->step = 1;
	459	s->val = s->max;
460
461	v4l2_sd_cfg->has_external_strobe = led_cfg->has_external_strobe;
462	}
463
464	static const struct v4l2_flash_ops v4l2_flash_ops = {
465	.external_strobe_set = aat1290_led_external_strobe_set,
466	.intensity_to_led_brightness = aat1290_intensity_to_brightness,
467	.led_brightness_to_intensity = aat1290_brightness_to_intensity,
468	};
469	#else
470	static inline void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
471	struct aat1290_led_config_data *led_cfg,
472	struct v4l2_flash_config *v4l2_sd_cfg)
473	{
474	}
475	static const struct v4l2_flash_ops v4l2_flash_ops;
476	#endif
477
49c34b8e JA	478	static const struct led_flash_ops flash_ops = {
	479	.strobe_set = aat1290_led_flash_strobe_set,
	480	.timeout_set = aat1290_led_flash_timeout_set,
	481	};
	482
	483	static int aat1290_led_probe(struct platform_device *pdev)
	484	{
	485	struct device *dev = &pdev->dev;
ac69b903	486	struct device_node *sub_node = NULL;
49c34b8e JA	487	struct aat1290_led *led;
	488	struct led_classdev *led_cdev;
	489	struct led_classdev_flash *fled_cdev;
	490	struct aat1290_led_config_data led_cfg = {};
ac69b903	491	struct v4l2_flash_config v4l2_sd_cfg = {};
49c34b8e JA	492	int ret;
	493
	494	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
	495	if (!led)
	496	return -ENOMEM;
	497
	498	led->pdev = pdev;
	499	platform_set_drvdata(pdev, led);
	500
	501	fled_cdev = &led->fled_cdev;
	502	fled_cdev->ops = &flash_ops;
	503	led_cdev = &fled_cdev->led_cdev;
	504
ac69b903	505	ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);
49c34b8e JA	506	if (ret < 0)
	507	return ret;
	508
	509	mutex_init(&led->lock);
	510
	511	/* Initialize LED Flash class device */
	512	led_cdev->brightness_set = aat1290_led_brightness_set;
	513	led_cdev->brightness_set_sync = aat1290_led_brightness_set_sync;
	514	led_cdev->max_brightness = led_cfg.max_brightness;
	515	led_cdev->flags \|= LED_DEV_CAP_FLASH;
	516	INIT_WORK(&led->work_brightness_set, aat1290_brightness_set_work);
	517
	518	aat1290_init_flash_timeout(led, &led_cfg);
	519
	520	/* Register LED Flash class device */
	521	ret = led_classdev_flash_register(&pdev->dev, fled_cdev);
	522	if (ret < 0)
	523	goto err_flash_register;
	524
ac69b903 JA	525	aat1290_init_v4l2_flash_config(led, &led_cfg, &v4l2_sd_cfg);
	526
	527	/* Create V4L2 Flash subdev. */
	528	led->v4l2_flash = v4l2_flash_init(dev, sub_node, fled_cdev, NULL,
	529	&v4l2_flash_ops, &v4l2_sd_cfg);
	530	if (IS_ERR(led->v4l2_flash)) {
	531	ret = PTR_ERR(led->v4l2_flash);
	532	goto error_v4l2_flash_init;
	533	}
	534
49c34b8e JA	535	return 0;
49c34b8e JA	536
ac69b903 JA	537	error_v4l2_flash_init:
ac69b903 JA	538	led_classdev_flash_unregister(fled_cdev);
49c34b8e JA	539	err_flash_register:
	540	mutex_destroy(&led->lock);
	541
	542	return ret;
	543	}
	544
	545	static int aat1290_led_remove(struct platform_device *pdev)
	546	{
	547	struct aat1290_led *led = platform_get_drvdata(pdev);
	548
ac69b903	549	v4l2_flash_release(led->v4l2_flash);
49c34b8e JA	550	led_classdev_flash_unregister(&led->fled_cdev);
	551	cancel_work_sync(&led->work_brightness_set);
	552
	553	mutex_destroy(&led->lock);
	554
	555	return 0;
	556	}
	557
	558	static const struct of_device_id aat1290_led_dt_match[] = {
	559	{ .compatible = "skyworks,aat1290" },
	560	{},
	561	};
93a51aa4	562	MODULE_DEVICE_TABLE(of, aat1290_led_dt_match);
49c34b8e JA	563
	564	static struct platform_driver aat1290_led_driver = {
	565	.probe = aat1290_led_probe,
	566	.remove = aat1290_led_remove,
	567	.driver = {
	568	.name = "aat1290",
	569	.of_match_table = aat1290_led_dt_match,
	570	},
	571	};
	572
	573	module_platform_driver(aat1290_led_driver);
	574
	575	MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@samsung.com>");
	576	MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs");
	577	MODULE_LICENSE("GPL v2");