summary refs log tree commit diff
path: root/drivers/leds/flash
diff options
context:
space:
mode:
authorLinus Walleij <linus.walleij@linaro.org>2021-05-28 22:23:59 +0200
committerPavel Machek <pavel@ucw.cz>2021-07-12 10:30:04 +0200
commit293fee7f607841cc128c3f6df9b464e8abf99fb0 (patch)
tree612ce59a2236997f36a61a3b1963bb180129ba2a /drivers/leds/flash
parente73f0f0ee7541171d89f2e2491130c7771ba58d3 (diff)
downloadlinux-293fee7f607841cc128c3f6df9b464e8abf99fb0.tar.gz
leds: aat1290: Move driver to flash subdirectory
We created a subdirectory for LED drivers that depend on
CONFIG_LEDS_CLASS_FLASH, and this driver does so let's
move it there.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Diffstat (limited to 'drivers/leds/flash')
-rw-r--r--drivers/leds/flash/Kconfig9
-rw-r--r--drivers/leds/flash/Makefile1
-rw-r--r--drivers/leds/flash/leds-aat1290.c556
3 files changed, 566 insertions, 0 deletions
diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig
index 3f49f3edbffb..736153b0bfd6 100644
--- a/drivers/leds/flash/Kconfig
+++ b/drivers/leds/flash/Kconfig
@@ -2,6 +2,15 @@
 
 if LEDS_CLASS_FLASH
 
+config LEDS_AAT1290
+	tristate "LED support for the AAT1290"
+	depends on V4L2_FLASH_LED_CLASS || !V4L2_FLASH_LED_CLASS
+	depends on GPIOLIB || COMPILE_TEST
+	depends on OF
+	depends on PINCTRL
+	help
+	  This option enables support for the LEDs on the AAT1290.
+
 config LEDS_RT4505
 	tristate "LED support for RT4505 flashlight controller"
 	depends on I2C && OF
diff --git a/drivers/leds/flash/Makefile b/drivers/leds/flash/Makefile
index 09aee561f769..11bec5881d51 100644
--- a/drivers/leds/flash/Makefile
+++ b/drivers/leds/flash/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
+obj-$(CONFIG_LEDS_AAT1290)	+= leds-aat1290.o
 obj-$(CONFIG_LEDS_RT4505)	+= leds-rt4505.o
 obj-$(CONFIG_LEDS_RT8515)	+= leds-rt8515.o
diff --git a/drivers/leds/flash/leds-aat1290.c b/drivers/leds/flash/leds-aat1290.c
new file mode 100644
index 000000000000..589484b22c79
--- /dev/null
+++ b/drivers/leds/flash/leds-aat1290.c
@@ -0,0 +1,556 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *	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>
+ */
+
+#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
+
+#define AAT1290_NAME			"aat1290"
+
+
+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 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(dev), NULL);
+	if (!child_node) {
+		dev_err(dev, "No DT child node found for connected LED.\n");
+		return -EINVAL;
+	}
+
+	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->dev->kobj.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 led_init_data init_data = {};
+	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);
+
+	init_data.fwnode = of_fwnode_handle(sub_node);
+	init_data.devicename = AAT1290_NAME;
+
+	/* Register LED Flash class device */
+	ret = led_classdev_flash_register_ext(&pdev->dev, fled_cdev,
+					      &init_data);
+	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 <j.anaszewski@samsung.com>");
+MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs");
+MODULE_LICENSE("GPL v2");