[PATCH v2 11/11] leds: aat1290: add support for V4L2 Flash sub-device

Jacek Anaszewski
2015-03-27T13:49:45Z

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@iki.fi>
---
drivers/leds/Kconfig | 1 +
drivers/leds/leds-aat1290.c | 150 ++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 149 insertions(+), 2 deletions(-)

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index c3b5b027..d73f43f 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -47,6 +47,7 @@ config LEDS_AAT1290
depends on LEDS_CLASS_FLASH
depends on GPIOLIB
depends on OF
+ depends on PINCTRL
help
This option enables support for the LEDs on the AAT1290.

diff --git a/drivers/leds/leds-aat1290.c b/drivers/leds/leds-aat1290.c
index acfae35..34fd5c4 100644
--- a/drivers/leds/leds-aat1290.c
+++ b/drivers/leds/leds-aat1290.c
@@ -17,9 +17,11 @@
#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.h>

#define AAT1290_MOVIE_MODE_CURRENT_ADDR 17
#define AAT1290_MAX_MM_CURR_PERCENT_0 16
@@ -53,11 +55,17 @@ struct aat1290_led {

/* 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;
+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+ /* movie mode current scale */
+ int *mm_current_scale;
+#endif

/* maximum flash timeout */
u32 max_flash_tm;
@@ -224,11 +232,16 @@ static int aat1290_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
return 0;
}

-static int aat1290_led_parse_dt(struct aat1290_led *led)
+static int aat1290_led_parse_dt(struct aat1290_led *led,
+ struct device_node **sub_node,
+ struct v4l2_flash_config *v4l2_sd_cfg)
{
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");
@@ -245,6 +258,17 @@ static int aat1290_led_parse_dt(struct aat1290_led *led)
return ret;
}

+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+ pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);
+ if (IS_ERR(pinctrl)) {
+ v4l2_sd_cfg->has_external_strobe = false;
+ dev_info(dev,
+ "No support for external strobe detected.\n");
+ } else {
+ v4l2_sd_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");
@@ -270,6 +294,8 @@ static int aat1290_led_parse_dt(struct aat1290_led *led)
return ret;
}

+ *sub_node = child_node;
+
return ret;
}

@@ -286,6 +312,100 @@ static void aat1290_init_flash_timeout(struct aat1290_led *led)
setting->val = setting->max;
}

+#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
+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;
+}
+
+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;
+}
+
+int init_mm_current_scale(struct aat1290_led *led)
+{
+ 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(led->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 void aat1290_init_v4l2_flash_config(struct aat1290_led *led,
+ 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->mm_current_scale[AAT1290_MM_CURRENT_SCALE_SIZE - 1];
+ s->step = 1;
+ s->val = s->max;
+}
+
+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
+#define aat1290_init_v4l2_flash_config(led, v4l2_sd_cfg)
+#define init_mm_current_scale(led) (0)
+#endif
+
static const struct led_flash_ops flash_ops = {
.strobe_set = aat1290_led_flash_strobe_set,
.timeout_set = aat1290_led_flash_timeout_set,
@@ -294,9 +414,11 @@ static const struct led_flash_ops flash_ops = {
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 v4l2_flash_config v4l2_sd_cfg = {};
int ret;

led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
@@ -310,7 +432,15 @@ static int aat1290_led_probe(struct platform_device *pdev)
fled_cdev->ops = &flash_ops;
led_cdev = &fled_cdev->led_cdev;

- ret = aat1290_led_parse_dt(led);
+ ret = aat1290_led_parse_dt(led, &sub_node, &v4l2_sd_cfg);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Init non-linear movie mode current scale basing
+ * on the max flash current from Device Tree binding.
+ */
+ ret = init_mm_current_scale(led);
if (ret < 0)
return ret;

@@ -330,8 +460,23 @@ static int aat1290_led_probe(struct platform_device *pdev)
if (ret < 0)
goto err_flash_register;

+ aat1290_init_v4l2_flash_config(led, &v4l2_sd_cfg);
+
+ led_cdev->dev->of_node = sub_node;
+
+ /* Create V4L2 Flash subdev. */
+ led->v4l2_flash = v4l2_flash_init(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);

@@ -342,6 +487,7 @@ 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->fled_cdev);
cancel_work_sync(&led->work_brightness_set);

--
1.7.9.5