[PATCH/RFC v9 19/19] leds: aat1290: add support for V4L2 Flash sub-device

[Jacek Anaszewski <j.anaszewski@samsung.com>]

Add support for V4L2 Flash sub-device to the aat1290 LED Flash class
driver. The support allows for V4L2 Flash sub-device to take the control
of the LED Flash class device.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Bryan Wu <cooloney@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/leds/leds-aat1290.c |   61 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/drivers/leds/leds-aat1290.c b/drivers/leds/leds-aat1290.c
index 15d969b..81a8f48 100644
--- a/drivers/leds/leds-aat1290.c
+++ b/drivers/leds/leds-aat1290.c
@@ -21,6 +21,7 @@
 #include <linux/gpio.h>
 #include <linux/of_gpio.h>
 #include <linux/of.h>
+#include <media/v4l2-flash.h>
 #include <linux/workqueue.h>
 
 #define AAT1290_MOVIE_MODE_CURRENT_ADDR	17
@@ -63,6 +64,7 @@ struct aat1290_led {
 	struct mutex lock;
 
 	struct led_classdev_flash ldev;
+	struct v4l2_flash *v4l2_flash;
 
 	int flen_gpio;
 	int en_set_gpio;
@@ -280,11 +282,51 @@ static void aat1290_init_flash_settings(struct aat1290_led *led,
 	setting->val = setting->max;
 }
 
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+static void aat1290_init_v4l2_ctrl_config(struct aat1290_led_settings *s,
+					struct v4l2_flash_ctrl_config *config)
+{
+	struct led_flash_setting *setting;
+	struct v4l2_ctrl_config *c;
+
+	c = &config->intensity;
+	setting = &s->torch_brightness;
+	c->min = setting->min;
+	c->max = setting->max;
+	c->step = setting->step;
+	c->def = setting->val;
+
+	c = &config->flash_timeout;
+	setting = &s->flash_timeout;
+	c->min = setting->min;
+	c->max = setting->max;
+	c->step = setting->step;
+	c->def = setting->val;
+
+	config->has_external_strobe = false;
+}
+#else
+#define aat1290_init_v4l2_ctrl_config(s, config)
+#endif
+
 static const struct led_flash_ops flash_ops = {
 	.strobe_set = aat1290_led_flash_strobe_set,
 	.timeout_set = aat1290_led_flash_timeout_set,
 };
 
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+static const struct v4l2_flash_ops v4l2_flash_ops = {
+	.external_strobe_set = NULL,
+};
+
+static const struct v4l2_flash_ops *get_v4l2_flash_ops(void)
+{
+	return &v4l2_flash_ops;
+}
+#else
+#define get_v4l2_flash_ops() (NULL)
+#endif
+
 static int aat1290_led_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -292,6 +334,9 @@ static int aat1290_led_probe(struct platform_device *pdev)
 	struct aat1290_led *led;
 	struct led_classdev *led_cdev;
 	struct led_classdev_flash *flash;
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+	struct v4l2_flash_ctrl_config v4l2_flash_config;
+#endif
 	struct aat1290_led_settings settings;
 	int flen_gpio, enset_gpio, ret;
 
@@ -344,6 +389,9 @@ static int aat1290_led_probe(struct platform_device *pdev)
 
 	flash->timeout = settings.flash_timeout;
 
+	/* Init V4L2 Flash controls basing on initialized settings */
+	aat1290_init_v4l2_ctrl_config(&settings, &v4l2_flash_config);
+
 	/* Init led class */
 	led_cdev = &flash->led_cdev;
 	led_cdev->name = led->label;
@@ -361,8 +409,20 @@ static int aat1290_led_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto error_gpio_en_set;
 
+	/* Create V4L2 Flash subdev. */
+	led->v4l2_flash = v4l2_flash_init(flash,
+					  get_v4l2_flash_ops(),
+					  dev_node,
+					  &v4l2_flash_config);
+	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(flash);
 error_gpio_en_set:
 	if (gpio_is_valid(enset_gpio))
 		gpio_free(enset_gpio);
@@ -378,6 +438,7 @@ 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->ldev);
 	cancel_work_sync(&led->work_brightness_set);
 
-- 
1.7.9.5