[PATCH v2 10/11] leds: max77693: add support for V4L2 Flash sub-device

Jacek Anaszewski
2015-03-27T13:49:44Z

Add support for V4L2 Flash sub-device to the max77693 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@iki.fi>
---
drivers/leds/leds-max77693.c | 125 ++++++++++++++++++++++++++++++++++++++++--
1 file changed, 119 insertions(+), 6 deletions(-)

diff --git a/drivers/leds/leds-max77693.c b/drivers/leds/leds-max77693.c
index 65c910d..91a4ec9 100644
--- a/drivers/leds/leds-max77693.c
+++ b/drivers/leds/leds-max77693.c
@@ -21,6 +21,7 @@
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
+#include <media/v4l2-flash.h>
#include <uapi/linux/leds.h>

#define MODE_OFF 0
@@ -65,6 +66,8 @@ struct max77693_sub_led {
struct led_classdev_flash fled_cdev;
/* assures led-triggers compatibility */
struct work_struct work_brightness_set;
+ /* V4L2 Flash device */
+ struct v4l2_flash *v4l2_flash;

/* brightness cache */
unsigned int torch_brightness;
@@ -642,7 +645,8 @@ static int max77693_led_flash_timeout_set(
}

static int max77693_led_parse_dt(struct max77693_led_device *led,
- struct max77693_led_config_data *cfg)
+ struct max77693_led_config_data *cfg,
+ struct device_node **sub_nodes)
{
struct device *dev = &led->pdev->dev;
struct max77693_sub_led *sub_leds = led->sub_leds;
@@ -688,6 +692,13 @@ static int max77693_led_parse_dt(struct max77693_led_device *led,
return -EINVAL;
}

+ if (sub_nodes[fled_id]) {
+ dev_err(dev,
+ "Conflicting \"led-sources\" DT properties\n");
+ return -EINVAL;
+ }
+
+ sub_nodes[fled_id] = child_node;
sub_leds[fled_id].fled_id = fled_id;

cfg->label[fled_id] =
@@ -776,11 +787,12 @@ static void max77693_led_validate_configuration(struct max77693_led_device *led,
}

static int max77693_led_get_configuration(struct max77693_led_device *led,
- struct max77693_led_config_data *cfg)
+ struct max77693_led_config_data *cfg,
+ struct device_node **sub_nodes)
{
int ret;

- ret = max77693_led_parse_dt(led, cfg);
+ ret = max77693_led_parse_dt(led, cfg, sub_nodes);
if (ret < 0)
return ret;

@@ -828,6 +840,66 @@ static void max77693_init_flash_settings(struct max77693_sub_led *sub_led,
setting->val = setting->max;
}

+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+
+static int max77693_led_external_strobe_set(
+ struct v4l2_flash *v4l2_flash,
+ bool enable)
+{
+ struct max77693_sub_led *sub_led =
+ flcdev_to_sub_led(v4l2_flash->fled_cdev);
+ struct max77693_led_device *led = sub_led_to_led(sub_led);
+ int fled_id = sub_led->fled_id;
+ int ret;
+
+ mutex_lock(&led->lock);
+
+ if (enable)
+ ret = max77693_add_mode(led, MODE_FLASH_EXTERNAL(fled_id));
+ else
+ ret = max77693_clear_mode(led, MODE_FLASH_EXTERNAL(fled_id));
+
+ mutex_unlock(&led->lock);
+
+ return ret;
+}
+
+static void max77693_init_v4l2_flash_config(struct max77693_sub_led *sub_led,
+ struct max77693_led_config_data *led_cfg,
+ struct v4l2_flash_config *v4l2_sd_cfg)
+{
+ struct max77693_led_device *led = sub_led_to_led(sub_led);
+ struct device *dev = &led->pdev->dev;
+ struct max77693_dev *iodev = dev_get_drvdata(dev->parent);
+ struct i2c_client *i2c = iodev->i2c;
+ struct led_flash_setting *s;
+
+ snprintf(v4l2_sd_cfg->dev_name, sizeof(v4l2_sd_cfg->dev_name),
+ "%s %d-%04x", sub_led->fled_cdev.led_cdev.name,
+ i2c_adapter_id(i2c->adapter), i2c->addr);
+
+ s = &v4l2_sd_cfg->intensity;
+ s->min = TORCH_IOUT_MIN;
+ s->max = sub_led->fled_cdev.led_cdev.max_brightness * TORCH_IOUT_STEP;
+ s->step = TORCH_IOUT_STEP;
+ s->val = s->max;
+
+ /* Init flash faults config */
+ v4l2_sd_cfg->flash_faults = LED_FAULT_OVER_VOLTAGE |
+ LED_FAULT_SHORT_CIRCUIT |
+ LED_FAULT_OVER_CURRENT;
+
+ v4l2_sd_cfg->has_external_strobe = true;
+}
+
+static const struct v4l2_flash_ops v4l2_flash_ops = {
+ .external_strobe_set = max77693_led_external_strobe_set,
+};
+
+#else
+#define max77693_init_v4l2_flash_config(sub_led, led_cfg, v4l2_sd_cfg)
+#endif
+
static void max77693_init_fled_cdev(struct max77693_sub_led *sub_led,
struct max77693_led_config_data *led_cfg)
{
@@ -859,12 +931,49 @@ static void max77693_init_fled_cdev(struct max77693_sub_led *sub_led,
sub_led->flash_timeout = fled_cdev->timeout.val;
}

+static int max77693_register_led(struct max77693_sub_led *sub_led,
+ struct max77693_led_config_data *led_cfg,
+ struct device_node *sub_node)
+{
+ struct max77693_led_device *led = sub_led_to_led(sub_led);
+ struct led_classdev_flash *fled_cdev = &sub_led->fled_cdev;
+ struct device *dev = &led->pdev->dev;
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+ struct v4l2_flash_config v4l2_sd_cfg = {};
+#endif
+ int ret;
+
+ /* Register in the LED subsystem */
+ ret = led_classdev_flash_register(dev, fled_cdev);
+ if (ret < 0)
+ return ret;
+
+ max77693_init_v4l2_flash_config(sub_led, led_cfg, &v4l2_sd_cfg);
+
+ fled_cdev->led_cdev.dev->of_node = sub_node;
+
+ /* Register in the V4L2 subsystem. */
+ sub_led->v4l2_flash = v4l2_flash_init(fled_cdev, &v4l2_flash_ops,
+ &v4l2_sd_cfg);
+ if (IS_ERR(sub_led->v4l2_flash)) {
+ ret = PTR_ERR(sub_led->v4l2_flash);
+ goto err_v4l2_flash_init;
+ }
+
+ return 0;
+
+err_v4l2_flash_init:
+ led_classdev_flash_unregister(fled_cdev);
+ return ret;
+}
+
static int max77693_led_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct max77693_dev *iodev = dev_get_drvdata(dev->parent);
struct max77693_led_device *led;
struct max77693_sub_led *sub_leds;
+ struct device_node *sub_nodes[2] = {};
struct max77693_led_config_data led_cfg = {};
int init_fled_cdev[2], i, ret;

@@ -878,7 +987,7 @@ static int max77693_led_probe(struct platform_device *pdev)
sub_leds = led->sub_leds;

platform_set_drvdata(pdev, led);
- ret = max77693_led_get_configuration(led, &led_cfg);
+ ret = max77693_led_get_configuration(led, &led_cfg, sub_nodes);
if (ret < 0)
return ret;

@@ -899,12 +1008,13 @@ static int max77693_led_probe(struct platform_device *pdev)
max77693_init_fled_cdev(&sub_leds[i], &led_cfg);

- /* Register LED Flash class device(s) */
+ /* Register LED Flash class and related V4L2 Flash device(s) */
for (i = FLED1; i <= FLED2; ++i) {
if (!init_fled_cdev[i])
continue;

- ret = led_classdev_flash_register(dev, &sub_leds[i].fled_cdev);
+ ret = max77693_register_led(&sub_leds[i], &led_cfg,
+ sub_nodes[i]);
if (ret < 0) {
/*
* At this moment FLED1 might have been already
@@ -923,6 +1033,7 @@ err_register_led2:
/* It is possible than only FLED2 was to be registered */
if (!init_fled_cdev[FLED1])
goto err_register_led1;
+ v4l2_flash_release(sub_leds[FLED1].v4l2_flash);
led_classdev_flash_unregister(&sub_leds[FLED1].fled_cdev);
err_register_led1:
mutex_destroy(&led->lock);
@@ -936,11 +1047,13 @@ static int max77693_led_remove(struct platform_device *pdev)
struct max77693_sub_led *sub_leds = led->sub_leds;

if (led->iout_joint || max77693_fled_used(led, FLED1)) {
+ v4l2_flash_release(sub_leds[FLED1].v4l2_flash);
led_classdev_flash_unregister(&sub_leds[FLED1].fled_cdev);
cancel_work_sync(&sub_leds[FLED1].work_brightness_set);
}

if (!led->iout_joint && max77693_fled_used(led, FLED2)) {
+ v4l2_flash_release(sub_leds[FLED2].v4l2_flash);
led_classdev_flash_unregister(&sub_leds[FLED2].fled_cdev);
cancel_work_sync(&sub_leds[FLED2].work_brightness_set);
}
--
1.7.9.5