adp1653: Add device tree bindings for LED controller

arch/arm/boot/dts/omap3-n900.dts line 566

Quoted 3 lines · Pavel Machek

[...]

arch/arm/boot/dts/omap3-n900.dts +2 -0

+	adp1653: adp1653 at 30 {
+		compatible = "ad,adp1653";

The Analog Devices vendor prefix is adi.

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

Hi Pavel,

Am 16.11.2014 um 08:59 schrieb Pavel Machek:

Quoted 2 lines

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

[...]

Quoted 6 lines

arch/arm/boot/dts/omap3-n900.dts +0 -0

index 739fcf2..ed0bfc1 100644
@@ -553,6 +561,18 @@
 

arch/arm/boot/dts/omap3-n900.dts line 565

Quoted 4 lines

arch/arm/boot/dts/omap3-n900.dts +2 -0

 		ti,usb-charger-detection = <&isp1704>;
 	};
+
+	adp1653: adp1653 at 30 {

This should probably be led-controller at 30 (a generic description not specific to the model). The label name is fine.

arch/arm/boot/dts/omap3-n900.dts line 574

Quoted 1 line

arch/arm/boot/dts/omap3-n900.dts +1 -0

+		gpios = <&gpio3 24 GPIO_ACTIVE_HIGH>; /* Want 88 */

At least to me, the meaning of "Want 88" is not clear - drop or clarify?

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

Signed-off-by Pavel Machek <[email protected]>

Thanks,
Pavel

Quoted 5 lines · On Sunday 16 November 2014 08:59:28 Pavel Machek wrote:

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

I think that this patch is probably not good and specially not for n900. adp1653 should be registered throw omap3 isp camera subsystem which does not have DT support yet.

See n900 legacy board camera code in file board-rx51-camera.c.

Hi!

Quoted 11 lines · Pali Roh?r

Quoted 6 lines · On Sunday 16 November 2014 08:59:28 Pavel Machek wrote:

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

I think that this patch is probably not good and specially not for n900. adp1653 should be registered throw omap3 isp camera subsystem which does not have DT support yet.

Can you explain?

adp1653 is independend device on i2c bus, and we have kernel driver for it (unlike rest of n900 camera system). Just now it is unusable due to lack of DT binding. It has two functions, LED light and a camera flash; yes, the second one should be integrated to the rest of camera system, but that is not yet merged. That should not prevent us from merging DT support for the flash, so that this part can be tested/maintained.

Quoted 2 lines

See n900 legacy board camera code in file
board-rx51-camera.c.

I have seen that.
Pavel

Quoted 17 lines · On Monday 17 November 2014 11:05:19 Pavel Machek wrote:

Hi!

Quoted 11 lines · Pali Roh?r

Quoted 6 lines · On Sunday 16 November 2014 08:59:28 Pavel Machek wrote:

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

I think that this patch is probably not good and specially not for n900. adp1653 should be registered throw omap3 isp camera subsystem which does not have DT support yet.

Can you explain?

Quoted 9 lines

adp1653 is independend device on i2c bus, and we have kernel driver for it (unlike rest of n900 camera system). Just now it is unusable due to lack of DT binding. It has two functions, LED light and a camera flash; yes, the second one should be integrated to the rest of camera system, but that is not yet merged. That should not prevent us from merging DT support for the flash, so that this part can be tested/maintained.

Ok. When ISP camera subsystem has DT support somebody will modify n900 DT to add camera flash from adp1653 to ISP... I believe it will not be hard.

Quoted 28 lines · Pali Roh?r

Quoted 26 lines · On Monday 17 November 2014 11:05:19 Pavel Machek wrote:

Hi!

Quoted 11 lines · Pali Roh?r

Quoted 6 lines · On Sunday 16 November 2014 08:59:28 Pavel Machek wrote:

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

I think that this patch is probably not good and specially not for n900. adp1653 should be registered throw omap3 isp camera subsystem which does not have DT support yet.

Can you explain?

adp1653 is independend device on i2c bus, and we have kernel driver for it (unlike rest of n900 camera system). Just now it is unusable due to lack of DT binding. It has two functions, LED light and a camera flash; yes, the second one should be integrated to the rest of camera system, but that is not yet merged. That should not prevent us from merging DT support for the flash, so that this part can be tested/maintained.

Quoted 3 lines

Ok. When ISP camera subsystem has DT support somebody will modify n900 DT to add camera flash from adp1653 to ISP... I believe it will not be hard.

Exactly. And yes, I'd like to get complete camera support for n900 merged. But first step is "make sure existing support does not break".

Quoted 29 lines · Pavel Machek

Quoted 28 lines · Pali Roh?r

Quoted 26 lines · On Monday 17 November 2014 11:05:19 Pavel Machek wrote:

Hi!

Quoted 5 lines · Pali Roh?r

Quoted 4 lines · On Sunday 16 November 2014 08:59:28 Pavel Machek wrote:

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

Quoted 7 lines

Quoted 2 lines

I'll clean up driver code a bit more, remove the
printks. Anything else obviously wrong?

I think that this patch is probably not good and specially not for n900. adp1653 should be registered throw omap3 isp camera subsystem which does not have DT support yet.

Can you explain?

adp1653 is independend device on i2c bus, and we have kernel driver for it (unlike rest of n900 camera system). Just now it is unusable due to lack of DT binding. It has two functions, LED light and a camera flash; yes, the second one should be integrated to the rest of camera system, but that is not yet merged. That should not prevent us from merging DT support for the flash, so that this part can be tested/maintained.

Quoted 7 lines

Quoted 3 lines

Ok. When ISP camera subsystem has DT support somebody will modify n900 DT to add camera flash from adp1653 to ISP... I believe it will not be hard.

Exactly. And yes, I'd like to get complete camera support for n900 merged. But first step is "make sure existing support does not break".

There's nothing stopping us from initializing the camera code from pdata-quirks.c for now to keep it working. Certainly the binding should be added to the driver, but that removes a dependency to the legacy booting mode if things are otherwise working.

Regards,

Tony

Quoted 44 lines · On Monday 17 November 2014 15:55:46 Tony Lindgren wrote:

Quoted 29 lines · Pavel Machek

Quoted 28 lines · Pali Roh?r

Quoted 26 lines · On Monday 17 November 2014 11:05:19 Pavel Machek wrote:

Hi!

Quoted 5 lines · Pali Roh?r

Quoted 4 lines · On Sunday 16 November 2014 08:59:28 Pavel Machek wrote:

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

Quoted 7 lines

Quoted 2 lines

I'll clean up driver code a bit more, remove the
printks. Anything else obviously wrong?

I think that this patch is probably not good and specially not for n900. adp1653 should be registered throw omap3 isp camera subsystem which does not have DT support yet.

Can you explain?

adp1653 is independend device on i2c bus, and we have kernel driver for it (unlike rest of n900 camera system). Just now it is unusable due to lack of DT binding. It has two functions, LED light and a camera flash; yes, the second one should be integrated to the rest of camera system, but that is not yet merged. That should not prevent us from merging DT support for the flash, so that this part can be tested/maintained.

Quoted 7 lines

Quoted 3 lines

Ok. When ISP camera subsystem has DT support somebody will modify n900 DT to add camera flash from adp1653 to ISP... I believe it will not be hard.

Exactly. And yes, I'd like to get complete camera support for n900 merged. But first step is "make sure existing support does not break".

There's nothing stopping us from initializing the camera code from pdata-quirks.c for now to keep it working. Certainly the binding should be added to the driver, but that removes a dependency to the legacy booting mode if things are otherwise working.

Quoted 3 lines

Regards,

Tony

Tony, legacy board code for n900 is not in mainline tree. And that omap3 camera subsystem for n900 is broken since 3.5 kernel... (both Front and Back camera on n900 show only green picture).

Hi Pali,

Quoted 8 lines · Pali Roh?r

Quoted 7 lines · On Monday 17 November 2014 15:55:46 Tony Lindgren wrote:

Quoted 6 lines · Pavel Machek

Quoted 5 lines · Pali Roh?r

Quoted 4 lines · On Monday 17 November 2014 11:05:19 Pavel Machek wrote:

Hi!

Quoted 1 line · Pali Roh?r

On Sunday 16 November 2014 08:59:28 Pavel Machek

Quoted 38 lines

Quoted 38 lines

Quoted 24 lines

Quoted 24 lines

Quoted 23 lines

Quoted 11 lines

Quoted 6 lines

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

I think that this patch is probably not good and specially not for n900. adp1653 should be registered throw omap3 isp camera subsystem which does not have DT support yet.

Can you explain?

adp1653 is independend device on i2c bus, and we have kernel driver for it (unlike rest of n900 camera system). Just now it is unusable due to lack of DT binding. It has two functions, LED light and a camera flash; yes, the second one should be integrated to the rest of camera system, but that is not yet merged. That should not prevent us from merging DT support for the flash, so that this part can be tested/maintained.

Quoted 7 lines

Quoted 3 lines

Ok. When ISP camera subsystem has DT support somebody will modify n900 DT to add camera flash from adp1653 to ISP... I believe it will not be hard.

Exactly. And yes, I'd like to get complete camera support for n900 merged. But first step is "make sure existing support does not break".

There's nothing stopping us from initializing the camera code from pdata-quirks.c for now to keep it working. Certainly the binding should be added to the driver, but that removes a dependency to the legacy booting mode if things are otherwise working.

Quoted 8 lines

Quoted 3 lines

Regards,

Tony

Tony, legacy board code for n900 is not in mainline tree. And that omap3 camera subsystem for n900 is broken since 3.5 kernel... (both Front and Back camera on n900 show only green picture).

Can you capture raw bayer images correctly? I assume green means YUV buffers that are all zero.

Do you know more specifically which patch breaks it?

Quoted 4 lines

Can you capture raw bayer images correctly? I assume green means YUV buffers that are all zero.

Do you know more specifically which patch breaks it?

CCing freemangordon (Ivaylo Dimitrov). He tried to debug it months ago but without success. Should know more info about this problem.

I think that commit which broke it was not bisected...

Quoted 6 lines · On Monday 17 November 2014 15:55:46 Tony Lindgren wrote:

There's nothing stopping us from initializing the camera code from pdata-quirks.c for now to keep it working. Certainly the binding should be added to the driver, but that removes a dependency to the legacy booting mode if things are otherwise working.

Tony, legacy board code for n900 is not in mainline tree. And that omap3 camera subsystem for n900 is broken since 3.5 kernel... (both Front and Back camera on n900 show only green picture).

Quoted 7 lines · Pali Roh?r

Quoted 5 lines · On Monday 17 November 2014 15:55:46 Tony Lindgren wrote:

There's nothing stopping us from initializing the camera code from pdata-quirks.c for now to keep it working. Certainly the binding should be added to the driver, but that removes a dependency to the legacy booting mode if things are otherwise working.

Quoted 4 lines

Tony, legacy board code for n900 is not in mainline tree. And that omap3 camera subsystem for n900 is broken since 3.5 kernel... (both Front and Back camera on n900 show only green picture).

I'm still seeing the legacy board code for n900 in mainline tree :) It's deprecated, but still there.

Are you maybe talking about some other piece of platform_data that's no longer in the mainline kernel?

No idea what might be wrong with the camera though.

Regards,

Tony

Quoted 8 lines · Pali Roh?r

Quoted 6 lines · On Monday 17 November 2014 15:55:46 Tony Lindgren wrote:

There's nothing stopping us from initializing the camera code from pdata-quirks.c for now to keep it working. Certainly the binding should be added to the driver, but that removes a dependency to the legacy booting mode if things are otherwise working.

Quoted 4 lines

Tony, legacy board code for n900 is not in mainline tree. And that omap3 camera subsystem for n900 is broken since 3.5 kernel... (both Front and Back camera on n900 show only green picture).

I'm still seeing the legacy board code for n900 in mainline tree :) It's deprecated, but still there.

Are you maybe talking about some other piece of platform_data that's no longer in the mainline kernel?

No idea what might be wrong with the camera though.

Quoted 20 lines · Tony Lindgren

Quoted 8 lines · Pali Roh?r

Quoted 6 lines · On Monday 17 November 2014 15:55:46 Tony Lindgren wrote:

There's nothing stopping us from initializing the camera code from pdata-quirks.c for now to keep it working. Certainly the binding should be added to the driver, but that removes a dependency to the legacy booting mode if things are otherwise working.

Quoted 4 lines

Tony, legacy board code for n900 is not in mainline tree. And that omap3 camera subsystem for n900 is broken since 3.5 kernel... (both Front and Back camera on n900 show only green picture).

I'm still seeing the legacy board code for n900 in mainline tree :) It's deprecated, but still there.

Are you maybe talking about some other piece of platform_data that's no longer in the mainline kernel?

Quoted 1 line

No idea what might be wrong with the camera though.

Camera support for main and secondary cameras was never mainline, AFAICT.

Merging it will not be easy, as it lacks DT support... and was broken for long time.

Anyway, flash is kind of important for me, since it makes phone useful as backup light; and it is simple piece of hw, so I intend to keep it useful.

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

Signed-off-by Pavel Machek <[email protected]>

Thanks,
Pavel

arch/arm/boot/dts/omap3-n900.dts +12 -0

index 739fcf2..ed0bfc1 100644
@@ -553,6 +561,18 @@
 
 		ti,usb-charger-detection = <&isp1704>;
 	};
+
+	adp1653: adp1653 at 30 {
+		compatible = "ad,adp1653";
+		reg = <0x30>;
+
+		max-flash-timeout-usec = <500000>;
+		max-flash-intensity-uA    = <320000>;
+		max-torch-intensity-uA     = <50000>;
+		max-indicator-intensity-uA = <17500>;
+
+		gpios = <&gpio3 24 GPIO_ACTIVE_HIGH>; /* Want 88 */
+	};
 };
 
 &i2c3 {

drivers/media/i2c/adp1653.c +96 -6

index 873fe19..e21ed02 100644
@@ -8,6 +8,7 @@
  * Contributors:
  *	Sakari Ailus <[email protected]>
  *	Tuukka Toivonen <[email protected]>
+ *      Pavel Machek <[email protected]>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License

@@ -34,9 +35,12 @@
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/slab.h>
+#include <linux/of_gpio.h>
 #include <media/adp1653.h>
 #include <media/v4l2-device.h>
 
+#include <linux/gpio.h>
+
 #define TIMEOUT_MAX		820000
 #define TIMEOUT_STEP		54600
 #define TIMEOUT_MIN		(TIMEOUT_MAX - ADP1653_REG_CONFIG_TMR_SET_MAX \

@@ -308,7 +316,16 @@ __adp1653_set_power(struct adp1653_flash *flash, int on)
 {
 	int ret;
 
-	ret = flash->platform_data->power(&flash->subdev, on);
+	if (flash->platform_data->power)
+		ret = flash->platform_data->power(&flash->subdev, on);
+	else {
+		gpio_set_value(flash->platform_data->power_gpio, on);
+		if (on) {
+			/* Some delay is apparently required. */
+			udelay(20);
+		}
+	}
+			
 	if (ret < 0)
 		return ret;
 

@@ -316,8 +333,13 @@ __adp1653_set_power(struct adp1653_flash *flash, int on)
 		return 0;
 
 	ret = adp1653_init_device(flash);
-	if (ret < 0)
+	if (ret >= 0)
+		return ret;
+
+	if (flash->platform_data->power)
 		flash->platform_data->power(&flash->subdev, 0);
+	else
+		gpio_set_value(flash->platform_data->power_gpio, 0);
 
 	return ret;
 }

@@ -407,21 +429,87 @@ static int adp1653_resume(struct device *dev)
 
 #endif /* CONFIG_PM */
 
+
+
+
+
+
+
+
+
+
+
+
+
+
+static int adp1653_of_init(struct i2c_client *client, struct adp1653_flash *flash, 
+			   struct device_node *node)
+{
+	u32 val;
+	struct adp1653_platform_data *pd;
+	enum of_gpio_flags flags;
+	int gpio;
+
+	if (!node)
+		return -EINVAL;
+
+	printk("adp1653: no platform data\n");
+	pd = devm_kzalloc(&client->dev, sizeof(*pd), GFP_KERNEL);
+	if (!pd)
+		return -ENOMEM;
+	flash->platform_data = pd;
+
+
+
+
+
+
+
+	if (of_property_read_u32(node, "max-flash-timeout-usec", &val)) return -EINVAL;
+	pd->max_flash_timeout = val;
+	if (of_property_read_u32(node, "max-flash-intensity-uA", &val)) return -EINVAL;
+	pd->max_flash_intensity = val/1000;
+	if (of_property_read_u32(node, "max-torch-intensity-uA", &val)) return -EINVAL;
+	pd->max_torch_intensity = val/1000;
+	if (of_property_read_u32(node, "max-indicator-intensity-uA", &val)) return -EINVAL;
+	pd->max_indicator_intensity = val;
+
+	if (!of_find_property(node, "gpios", NULL)) {
+		printk("No gpio node\n");
+		return -EINVAL;
+	}
+
+	gpio = of_get_gpio_flags(node, 0, &flags);
+	if (gpio < 0) {
+		printk("Error getting GPIO\n"); 
+		return -EINVAL;
+	}
+
+	pd->power_gpio = gpio;
+
+	return 0;
+}
+
+
 static int adp1653_probe(struct i2c_client *client,
 			 const struct i2c_device_id *devid)
 {
 	struct adp1653_flash *flash;
 	int ret;
 
-	/* we couldn't work without platform data */
-	if (client->dev.platform_data == NULL)
-		return -ENODEV;
+	printk("adp1653: probe\n");
 
 	flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
 	if (flash == NULL)
 		return -ENOMEM;
 
-	flash->platform_data = client->dev.platform_data;
+	/* we couldn't work without platform data */
+	if (client->dev.platform_data == NULL) {
+		ret = adp1653_of_init(client, flash, client->dev.of_node);
+		if (ret)
+			return ret;
+	} else
+		flash->platform_data = client->dev.platform_data;
 
 	mutex_init(&flash->power_lock);
 

@@ -439,9 +527,15 @@ static int adp1653_probe(struct i2c_client *client,
 
 	flash->subdev.entity.type = MEDIA_ENT_T_V4L2_SUBDEV_FLASH;
 
+	__adp1653_set_power(flash, 1);
+
+	__adp1653_set_power(flash, 0);
+	printk("Flash should have blinked\n");
+
 	return 0;
 
 free_and_quit:
+	printk("adp1653: something failed registering\n");
 	v4l2_ctrl_handler_free(&flash->ctrls);
 	return ret;
 }

include/media/adp1653.h +5 -3

index 1d9b48a..b556580 100644
@@ -100,9 +100,11 @@ struct adp1653_platform_data {
 	int (*power)(struct v4l2_subdev *sd, int on);
 
 	u32 max_flash_timeout;		/* flash light timeout in us */
-	u32 max_flash_intensity;	/* led intensity, flash mode */
-	u32 max_torch_intensity;	/* led intensity, torch mode */
-	u32 max_indicator_intensity;	/* indicator led intensity */
+	u32 max_flash_intensity;	/* led intensity, flash mode, mA */
+	u32 max_torch_intensity;	/* led intensity, torch mode, mA */
+	u32 max_indicator_intensity;	/* indicator led intensity, uA */
+
+	int power_gpio;			/* for device-tree based boot */
 };
 
 #define to_adp1653_flash(sd)	container_of(sd, struct adp1653_flash, subdev)

Signature · 3 lines

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Hi Pavel,

Quoted 3 lines · Pavel Machek

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

Quoted 2 lines

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

Jacek Anaszewski is working on flash support for LED devices. I think it'd be good to sync the DT bindings for the two, as the types of devices supported by the LED API and the V4L2 flash API are quite similar.

Cc Jacek.

Hi Pavel, Sakari,

Quoted 13 lines · Sakari Ailus

Hi Pavel,

Quoted 5 lines · Pavel Machek

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

Jacek Anaszewski is working on flash support for LED devices. I think it'd be good to sync the DT bindings for the two, as the types of devices supported by the LED API and the V4L2 flash API are quite similar.

Quoted 1 line

Cc Jacek.

I've already submitted a patch [1] that updates leds common bindings. I hasn't been merged yet, as the related LED Flash class patch [2] still needs some indicator leds related discussion [3].

I think this is a good moment to discuss the flash related led common bindings.

[1] http://www.spinics.net/lists/linux-leds/msg02121.html

[2] http://www.spinics.net/lists/linux-media/msg83100.html
[3] http://www.spinics.net/lists/linux-leds/msg02472.html

Quoted 22 lines · Jacek Anaszewski

Hi Pavel, Sakari,

Quoted 6 lines · Sakari Ailus

Hi Pavel,

Quoted 3 lines · Pavel Machek

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

Quoted 8 lines

Quoted 2 lines

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

Jacek Anaszewski is working on flash support for LED devices. I think it'd be good to sync the DT bindings for the two, as the types of devices supported by the LED API and the V4L2 flash API are quite similar.

Cc Jacek.

I've already submitted a patch [1] that updates leds common bindings. I hasn't been merged yet, as the related LED Flash class patch [2] still needs some indicator leds related discussion [3].

Quoted 2 lines

I think this is a good moment to discuss the flash related led common bindings.

Part of problem is that adp1653 is not regarded as "LED" device by current kernel driver.

Quoted 1 line

[1] http://www.spinics.net/lists/linux-leds/msg02121.html

(quoted diff) +16 -0

@@ -3,6 +3,17 @@ Common leds properties.
  Optional properties for child nodes:
  - label : The label for this LED.  If omitted, the label is
    taken from the node name (excluding the unit address).
+- iout-torch : Array of maximum intensities in microamperes of the
  torch
+	led currents in order from sub-led 0 to N-1, where N is the
  number
+	of torch sub-leds exposed by the device
+- iout-flash : Array of maximum intensities in microamperes of the
  flash
+	led currents in order from sub-led 0 to N-1, where N is the
  number
+	of flash sub-leds exposed by the device
+- iout-indicator : Array of maximum intensities in microamperes of
+  the indicator led currents in order from sub-led 0 to N-1,
+  where N is the number of indicator sub-leds exposed by the device
+- flash-timeout : timeout in microseconds after which flash led
+  is turned off
 
  - linux,default-trigger :  This parameter, if present, is a
      string defining the trigger assigned to the LED.  Current
      triggers are:

@@ -19,5 +30,10 @@ Examples:
  system-status {
  	       label = "Status";
  	       linux,default-trigger = "heartbeat";
+	       iout-torch = <500 500>;
+	       iout-flash = <1000 1000>;
+	       iout-indicator = <100 100>;
+	       flash-timeout = <1000>;
+
...
  };

I don't get it; system-status describes single LED, why are iout-torch (and friends) arrays of two?

Also, at least on adp1653, these are actually two leds -- white and red. Torch and flash is white led, indicator is red led.

Quoted 2 lines

[2] http://www.spinics.net/lists/linux-media/msg83100.html
[3] http://www.spinics.net/lists/linux-leds/msg02472.html

What device are you using for testing? Can you cc me on future patches?

Why do we need complex "flash LED class" support, and where is the V4L2 glue?

Quoted 10 lines

Quoted 7 lines

I've already submitted a patch [1] that updates leds common bindings. I hasn't been merged yet, as the related LED Flash class patch [2] still needs some indicator leds related discussion [3].

I think this is a good moment to discuss the flash related led common bindings.

Part of problem is that adp1653 is not regarded as "LED" device by current kernel driver.

It doesn't prevent us from keeping the flash devices related DT bindings unified across kernel subsystems. The DT bindings docs for the adp1653 could just provide a reference to the led/common.txt bindings. In the future, when LED Flash class will be merged, all the V4L2 Flash drivers might be moved to the LED subsystem to gain the LED subsystem support.

Quoted 12 lines

(quoted diff) +5 -0

@@ -19,5 +30,10 @@ Examples:
 system-status {
 	       label = "Status";
 	       linux,default-trigger = "heartbeat";
+	       iout-torch = <500 500>;
+	       iout-flash = <1000 1000>;
+	       iout-indicator = <100 100>;
+	       flash-timeout = <1000>;
+
...
 };

Quoted 2 lines

I don't get it; system-status describes single LED, why are iout-torch (and friends) arrays of two?

Some devices can control more than one led. The array is for such purposes. The system-status should be probably renamed to something more generic for both common leds and flash leds, e.g. system-led.

Quoted 2 lines

Also, at least on adp1653, these are actually two leds -- white and red. Torch and flash is white led, indicator is red led.

Then you should define three properties:

iout-torch = <[uA]>;
iout-flash = <[uA]>;
iout-indicator = <[uA]>;

iout-torch and iout-flash properties would determine the current for the white led in the torch and flash modes respectively and the iout-indicator property would determine the current for the indicator led.

Quoted 5 lines

Quoted 2 lines

[2] http://www.spinics.net/lists/linux-media/msg83100.html
[3] http://www.spinics.net/lists/linux-leds/msg02472.html

What device are you using for testing? Can you cc me on future patches?

I am using max77693 [1] and aat1290 [2]. OK, I will add you on cc.

The v4l2-flash sub-device registers with v4l2-async API in a media device. Exemplary support for v4l2-flash sub-devices is added to the exynos4-is driver in the patch [5].

Quoted 11 lines

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Quoted 7 lines

I've already submitted a patch [1] that updates leds common bindings. I hasn't been merged yet, as the related LED Flash class patch [2] still needs some indicator leds related discussion [3].

I think this is a good moment to discuss the flash related led common bindings.

Part of problem is that adp1653 is not regarded as "LED" device by current kernel driver.

Quoted 6 lines

It doesn't prevent us from keeping the flash devices related DT bindings unified across kernel subsystems. The DT bindings docs for the adp1653 could just provide a reference to the led/common.txt bindings. In the future, when LED Flash class will be merged, all the V4L2 Flash drivers might be moved to the LED subsystem to gain the LED subsystem support.

Yeah, that makses sense.

Quoted 12 lines

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(quoted diff) +5 -0

@@ -19,5 +30,10 @@ Examples:
  system-status {
  	       label = "Status";
  	       linux,default-trigger = "heartbeat";
+	       iout-torch = <500 500>;
+	       iout-flash = <1000 1000>;
+	       iout-indicator = <100 100>;
+	       flash-timeout = <1000>;
+
...
  };

Quoted 7 lines

Quoted 2 lines

I don't get it; system-status describes single LED, why are iout-torch (and friends) arrays of two?

Some devices can control more than one led. The array is for such purposes. The system-status should be probably renamed to something more generic for both common leds and flash leds, e.g. system-led.

No, sorry. The Documentation/devicetree/bindings/leds/common.txt describes binding for _one LED_. Yes, your device can have two leds, so your devices should have two such blocks in the device tree... Each led should have its own label and default trigger, for example. And I guess flash-timeout be per-LED, too.

Would it make sense to include "-uA" and "-usec" suffixes in the dt property names?

Quoted 5 lines

Quoted 2 lines

Also, at least on adp1653, these are actually two leds -- white and red. Torch and flash is white led, indicator is red led.

Then you should define three properties:

Quoted 8 lines

iout-torch = <[uA]>;
iout-flash = <[uA]>;
iout-indicator = <[uA]>;

iout-torch and iout-flash properties would determine the current for the white led in the torch and flash modes respectively and the iout-indicator property would determine the current for the indicator led.

Yes, that would work. I have used

arch/arm/boot/dts/omap3-n900.dts +4 -0

+               max-flash-timeout-usec = <500000>;
+               max-flash-intensity-uA     = <320000>;
+               max-torch-intensity-uA     =  <50000>;
+               max-indicator-intensity-uA =  <17500>;

. Which is pretty similar. (Actually, maybe the longer property names are easier to understand for more people?) (And yes, I should probably separate red and white led into separate groups).

Quoted 6 lines

Quoted 5 lines

Quoted 2 lines

[2] http://www.spinics.net/lists/linux-media/msg83100.html
[3] http://www.spinics.net/lists/linux-leds/msg02472.html

What device are you using for testing? Can you cc me on future patches?

Quoted 1 line

I am using max77693 [1] and aat1290 [2]. OK, I will add you on cc.

Thanks for cc and thanks for links!

I see max77693 has two different "white" leds, aat1290 has one "white" led, and neither of them has secondary red led for indication?

Quoted 3 lines

The v4l2-flash sub-device registers with v4l2-async API in a media device. Exemplary support for v4l2-flash sub-devices is added to the exynos4-is driver in the patch [5].

Thanks for the links. It seems that aside from moving adp1653 driver to device tree, it should be moved to the LED framework, but that's a topic for another patch.

Quoted 20 lines

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(quoted diff) +5 -0

@@ -19,5 +30,10 @@ Examples:
 system-status {
 	       label = "Status";
 	       linux,default-trigger = "heartbeat";
+	       iout-torch = <500 500>;
+	       iout-flash = <1000 1000>;
+	       iout-indicator = <100 100>;
+	       flash-timeout = <1000>;
+
...
 };

Quoted 7 lines

Quoted 2 lines

I don't get it; system-status describes single LED, why are iout-torch (and friends) arrays of two?

Some devices can control more than one led. The array is for such purposes. The system-status should be probably renamed to something more generic for both common leds and flash leds, e.g. system-led.

Quoted 5 lines

No, sorry. The Documentation/devicetree/bindings/leds/common.txt describes binding for _one LED_. Yes, your device can have two leds, so your devices should have two such blocks in the device tree... Each led should have its own label and default trigger, for example. And I guess flash-timeout be per-LED, too.

I think that a device tree binding describes a single physical device. No matter how many sub-leds a device controls, it is still one piece of hardware.

default-trigger property should also be an array of strings.

I agree that flash-timeout should be per led - an array, similarly as in case of iout's.

Quoted 4 lines

Quoted 3 lines

The v4l2-flash sub-device registers with v4l2-async API in a media device. Exemplary support for v4l2-flash sub-devices is added to the exynos4-is driver in the patch [5].

Quoted 3 lines

Thanks for the links. It seems that aside from moving adp1653 driver to device tree, it should be moved to the LED framework, but that's a topic for another patch.

Like I mentioned in the previous message the LED Flash class patch isn't in its final shape yet. Nonetheless I think that we should agree on the leds/common.txt documentation improvements and define DT documentation for adp1653 accordingly.

Hi!

Quoted 26 lines

Quoted 20 lines

Quoted 12 lines

Quoted 12 lines

(quoted diff) +5 -0

@@ -19,5 +30,10 @@ Examples:
  system-status {
  	       label = "Status";
  	       linux,default-trigger = "heartbeat";
+	       iout-torch = <500 500>;
+	       iout-flash = <1000 1000>;
+	       iout-indicator = <100 100>;
+	       flash-timeout = <1000>;
+
...
  };

Quoted 7 lines

Quoted 2 lines

I don't get it; system-status describes single LED, why are iout-torch (and friends) arrays of two?

Some devices can control more than one led. The array is for such purposes. The system-status should be probably renamed to something more generic for both common leds and flash leds, e.g. system-led.

Quoted 5 lines

No, sorry. The Documentation/devicetree/bindings/leds/common.txt describes binding for _one LED_. Yes, your device can have two leds, so your devices should have two such blocks in the device tree... Each led should have its own label and default trigger, for example. And I guess flash-timeout be per-LED, too.

Quoted 3 lines

I think that a device tree binding describes a single physical device. No matter how many sub-leds a device controls, it is still one piece of hardware.

You got this wrong, sorry.

In my case, there are three physical devices:

adp1653
white LED
red LED

Each LED should have an label, and probably default trigger -- default trigger for red one should be "we are recording video" and for white should be "this is flash for default camera".

If the hardware LED changes with one that needs different current, the block for the adp1653 stays the same, but white LED block should be updated with different value.

Quoted 1 line

default-trigger property should also be an array of strings.

That is not how it currently works.

Quoted 3 lines

I agree that flash-timeout should be per led - an array, similarly as in case of iout's.

Agreed about per-led, disagreed about the array. As all the fields would need arrays, and as LED system currently does not use arrays for label and linux,default-trigger, I believe we should follow existing design and model it as three devices. (It _is_ physically three devices.)

Quoted 3 lines

If the hardware LED changes with one that needs different current, the block for the adp1653 stays the same, but white LED block should be updated with different value.

I think that you are talking about sub nodes. Indeed I am leaning towards this type of design.

Quoted 7 lines

Quoted 2 lines

I agree that flash-timeout should be per led - an array, similarly as in case of iout's.

Agreed about per-led, disagreed about the array. As all the fields would need arrays, and as LED system currently does not use arrays for label and linux,default-trigger, I believe we should follow existing design and model it as three devices. (It _is_ physically three devices.)

Right, I missed that the leds/common.txt describes child node.

I propose following modifications to the binding:

Optional properties for child nodes:
- iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- iout-mode-flash : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
- iout-mode-indicator : initial intensity in microamperes of the indicator LED; it is required to enable support for the indicator led

- max-iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- max-iout-mode-flash : maximum intensity in microamperes of the flash LED
- max-iout-mode-indicator : maximum intensity in microamperes of the indicator LED
- flash-timeout : timeout in microseconds after which flash
led is turned off

I propose to avoid name "torch", as for ordinary leds it would be misleading.

Hi!

Quoted 6 lines

Quoted 3 lines

If the hardware LED changes with one that needs different current, the block for the adp1653 stays the same, but white LED block should be updated with different value.

I think that you are talking about sub nodes. Indeed I am leaning towards this type of design.

I think I am :-).

Quoted 21 lines

Quoted 7 lines

Quoted 2 lines

I agree that flash-timeout should be per led - an array, similarly as in case of iout's.

Agreed about per-led, disagreed about the array. As all the fields would need arrays, and as LED system currently does not use arrays for label and linux,default-trigger, I believe we should follow existing design and model it as three devices. (It _is_ physically three devices.)

Right, I missed that the leds/common.txt describes child node.

I propose following modifications to the binding:

Optional properties for child nodes:
- iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- iout-mode-flash : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
- iout-mode-indicator : initial intensity in microamperes of the indicator LED; it is required to enable support for the indicator led

Quoted 8 lines

- max-iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- max-iout-mode-flash : maximum intensity in microamperes of the flash LED
- max-iout-mode-indicator : maximum intensity in microamperes of the indicator LED
- flash-timeout : timeout in microseconds after which flash
led is turned off

Ok, I took a look, and "iout" is notation I understand, but people may have trouble with and I don't see it used anywhere else.

Also... do we need both "current" and "max-current" properties?

But regulators already have "regulator-max-microamp" property. So what about:

max-microamp : maximum intensity in microamperes of the LED
(torch LED for flash devices)
max-flash-microamp : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
flash-timeout-microseconds : timeout in microseconds after which flash
led is turned off

If you had indicator on the same led, I guess

indicator-microamp : recommended intensity in microamperes of the LED
for indication

...would do?

Hi Pavel, Sakari,

Quoted 62 lines · Pavel Machek

Hi!

Quoted 6 lines

Quoted 3 lines

If the hardware LED changes with one that needs different current, the block for the adp1653 stays the same, but white LED block should be updated with different value.

I think that you are talking about sub nodes. Indeed I am leaning towards this type of design.

I think I am :-).

Quoted 22 lines

Quoted 8 lines

Quoted 2 lines

I agree that flash-timeout should be per led - an array, similarly as in case of iout's.

Agreed about per-led, disagreed about the array. As all the fields would need arrays, and as LED system currently does not use arrays for label and linux,default-trigger, I believe we should follow existing design and model it as three devices. (It _is_ physically three devices.)

Right, I missed that the leds/common.txt describes child node.

I propose following modifications to the binding:

Optional properties for child nodes:
- iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- iout-mode-flash : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
- iout-mode-indicator : initial intensity in microamperes of the indicator LED; it is required to enable support for the indicator led

Quoted 8 lines

- max-iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- max-iout-mode-flash : maximum intensity in microamperes of the flash LED
- max-iout-mode-indicator : maximum intensity in microamperes of the indicator LED
- flash-timeout : timeout in microseconds after which flash
led is turned off

Ok, I took a look, and "iout" is notation I understand, but people may have trouble with and I don't see it used anywhere else.

Also... do we need both "current" and "max-current" properties?

But regulators already have "regulator-max-microamp" property. So what about:

max-microamp : maximum intensity in microamperes of the LED
(torch LED for flash devices)
max-flash-microamp : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
flash-timeout-microseconds : timeout in microseconds after which flash
led is turned off

If you had indicator on the same led, I guess

indicator-microamp : recommended intensity in microamperes of the LED
for indication

Quoted 2 lines

...would do?

Ongoing discussion allowed me for taking a look at the indicator issue from different perspective. This is also vital for the issue of whether a v4l2-flash sub-device should be created per device or per sub-led [1].

Currently each sub-led is represented as a separate device tree sub node and the led drivers create separate LED class device for the sub nodes. What this implies is that indicator led also must be represented by the separate LED class device.

This is contrary to the way how V4L2 Flash API approaches this issue, as it considers a flash device as a regulator chip driven through a bus. The API allows to set the led in torch or flash mode and implicitly assumes that there can be additional indicator led supported, which can't be turned on separately, but the drivers apply the indicator current to the indicator led when the torch or flash led is activated.

I propose to create separate v4l2-flash device for the indicator led, and treat it as a regular sub-led similarly like it is done in the LED subsystem. LED Flash class driver would only add a flag LED_DEV_CAP_INDICATOR and basing on it the v4l2-flash sub-device would create only V4L2_CID_FLASH_INDICATOR_INTENSITY control for it. There could ba also additional control added:
V4L2_CID_FLASH_INDICATOR_PATTERN to support the feature supported by some LED class drivers.

From the media device perspective such an approach would be harmful, as the indicator led could be turned on right before strobing the flash or turning the torch on, by separate calls to different v4l2-flash sub-devices.

The design described above would allow for avoiding issues I touched in the message [1].

Hi Jacek and Pavel,

Quoted 65 lines · Jacek Anaszewski

Hi Pavel, Sakari,

Quoted 62 lines · Pavel Machek

Hi!

Quoted 6 lines

Quoted 3 lines

If the hardware LED changes with one that needs different current, the block for the adp1653 stays the same, but white LED block should be updated with different value.

I think that you are talking about sub nodes. Indeed I am leaning towards this type of design.

I think I am :-).

Quoted 22 lines

Quoted 8 lines

Quoted 2 lines

I agree that flash-timeout should be per led - an array, similarly as in case of iout's.

Agreed about per-led, disagreed about the array. As all the fields would need arrays, and as LED system currently does not use arrays for label and linux,default-trigger, I believe we should follow existing design and model it as three devices. (It _is_ physically three devices.)

Right, I missed that the leds/common.txt describes child node.

I propose following modifications to the binding:

Optional properties for child nodes:
- iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- iout-mode-flash : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
- iout-mode-indicator : initial intensity in microamperes of the indicator LED; it is required to enable support for the indicator led

Quoted 8 lines

- max-iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- max-iout-mode-flash : maximum intensity in microamperes of the flash LED
- max-iout-mode-indicator : maximum intensity in microamperes of the indicator LED
- flash-timeout : timeout in microseconds after which flash
led is turned off

Ok, I took a look, and "iout" is notation I understand, but people may have trouble with and I don't see it used anywhere else.

Also... do we need both "current" and "max-current" properties?

But regulators already have "regulator-max-microamp" property. So what about:

max-microamp : maximum intensity in microamperes of the LED
(torch LED for flash devices)
max-flash-microamp : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
flash-timeout-microseconds : timeout in microseconds after which flash
led is turned off

If you had indicator on the same led, I guess

indicator-microamp : recommended intensity in microamperes of the LED
for indication

The value for the indicator is maximum as well, not just a recommendation.

Quoted 14 lines

Quoted 2 lines

...would do?

Ongoing discussion allowed me for taking a look at the indicator issue from different perspective. This is also vital for the issue of whether a v4l2-flash sub-device should be created per device or per sub-led [1].

Currently each sub-led is represented as a separate device tree sub node and the led drivers create separate LED class device for the sub nodes. What this implies is that indicator led also must be represented by the separate LED class device.

Quoted 7 lines

This is contrary to the way how V4L2 Flash API approaches this issue, as it considers a flash device as a regulator chip driven through a bus. The API allows to set the led in torch or flash mode and implicitly assumes that there can be additional indicator led supported, which can't be turned on separately, but the drivers apply the indicator current to the indicator led when the torch or flash led is activated.

The indicator is independent of the flash LED in V4L2 flash API. At least that's how it should be, and in adp1653 the two are independent, but the as3645a can't use indicator with the flash AFAIR.

Quoted 8 lines

I propose to create separate v4l2-flash device for the indicator led, and treat it as a regular sub-led similarly like it is done in the LED subsystem. LED Flash class driver would only add a flag LED_DEV_CAP_INDICATOR and basing on it the v4l2-flash sub-device would create only V4L2_CID_FLASH_INDICATOR_INTENSITY control for it. There could ba also additional control added:
V4L2_CID_FLASH_INDICATOR_PATTERN to support the feature supported by some LED class drivers.

Interesting idea.

The flash controller is still a single I2C device with common set of faults, for instance. Some devices refuse to work again in case of faults until they are cleared (= read).

Could the indicator pattern control be present in the same sub-device?

Are there any flash LED controllers that support such functionality?

Quoted 7 lines

From the media device perspective such an approach would
be harmful, as the indicator led could be turned on right before strobing the flash or turning the torch on, by separate calls to different v4l2-flash sub-devices.

The design described above would allow for avoiding issues I touched in the message [1].

Let me reply this separately. Feel free to ping me if I obviously appear to miss something.

Quoted 11 lines

Quoted 11 lines

But regulators already have "regulator-max-microamp" property. So what about:

max-microamp : maximum intensity in microamperes of the LED
(torch LED for flash devices)
max-flash-microamp : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
flash-timeout-microseconds : timeout in microseconds after which flash
led is turned off

Quoted 4 lines

Quoted 4 lines

If you had indicator on the same led, I guess

indicator-microamp : recommended intensity in microamperes of the LED
for indication

The value for the indicator is maximum as well, not just a recommendation.

I would also swap the segments of a property name to follow the convention as in case of "regulator-max-microamp".

Updated version:

==========================================================

Optional properties for child nodes:
- max-microamp : maximum intensity in microamperes of the LED (torch LED for flash devices)
- flash-max-microamp : maximum intensity in microamperes of the flash LED; it is mandatory if the led should support the flash mode
- flash-timeout-microsec : timeout in microseconds after which the flash led is turned off

- indicator-pattern : identifier of the blinking pattern for the indicator led

Hi!

Quoted 7 lines

I would also swap the segments of a property name to follow the convention as in case of "regulator-max-microamp".

Updated version:

==========================================================

Quoted 8 lines

Optional properties for child nodes:
- max-microamp : maximum intensity in microamperes of the LED (torch LED for flash devices)
- flash-max-microamp : maximum intensity in microamperes of the flash LED; it is mandatory if the led should support the flash mode
- flash-timeout-microsec : timeout in microseconds after which the flash led is turned off

Works for me. Do you want to submit a patch or should I do it?

Quoted 4 lines

- indicator-pattern : identifier of the blinking pattern for the indicator led

This would need a bit more documentation, no?

Hi Pavel, Sakari,

Quoted 58 lines · Pavel Machek

Hi!

Quoted 6 lines

Quoted 3 lines

If the hardware LED changes with one that needs different current, the block for the adp1653 stays the same, but white LED block should be updated with different value.

I think that you are talking about sub nodes. Indeed I am leaning towards this type of design.

I think I am :-).

Quoted 22 lines

Quoted 8 lines

Quoted 2 lines

I agree that flash-timeout should be per led - an array, similarly as in case of iout's.

Agreed about per-led, disagreed about the array. As all the fields would need arrays, and as LED system currently does not use arrays for label and linux,default-trigger, I believe we should follow existing design and model it as three devices. (It _is_ physically three devices.)

Right, I missed that the leds/common.txt describes child node.

I propose following modifications to the binding:

Optional properties for child nodes:
- iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- iout-mode-flash : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
- iout-mode-indicator : initial intensity in microamperes of the indicator LED; it is required to enable support for the indicator led

Quoted 8 lines

- max-iout-mode-led : maximum intensity in microamperes of the LED
(torch LED for flash devices)
- max-iout-mode-flash : maximum intensity in microamperes of the flash LED
- max-iout-mode-indicator : maximum intensity in microamperes of the indicator LED
- flash-timeout : timeout in microseconds after which flash
led is turned off

Ok, I took a look, and "iout" is notation I understand, but people may have trouble with and I don't see it used anywhere else.

Also... do we need both "current" and "max-current" properties?

But regulators already have "regulator-max-microamp" property. So what about:

max-microamp : maximum intensity in microamperes of the LED
(torch LED for flash devices)
max-flash-microamp : initial intensity in microamperes of the
flash LED; it is required to enable support for the flash led
flash-timeout-microseconds : timeout in microseconds after which flash
led is turned off

Quoted 6 lines

If you had indicator on the same led, I guess

indicator-microamp : recommended intensity in microamperes of the LED
for indication

...would do?

Ongoing discussion allowed me for taking a look at the indicator issue from different perspective. This is also vital for the issue of whether a v4l2-flash sub-device should be created per device or per sub-led [1].

Currently each sub-led is represented as a separate device tree sub node and the led drivers create separate LED class device for the sub nodes. What this implies is that indicator led also must be represented by the separate LED class device.

This is contrary to the way how V4L2 Flash API approaches this issue, as it considers a flash device as a regulator chip driven through a bus. The API allows to set the led in torch or flash mode and implicitly assumes that there can be additional indicator led supported, which can't be turned on separately, but the drivers apply the indicator current to the indicator led when the torch or flash led is activated.

I propose to create separate v4l2-flash device for the indicator led, and treat it as a regular sub-led similarly like it is done in the LED subsystem. LED Flash class driver would only add a flag LED_DEV_CAP_INDICATOR and basing on it the v4l2-flash sub-device would create only V4L2_CID_FLASH_INDICATOR_INTENSITY control for it. There could ba also additional control added:
V4L2_CID_FLASH_INDICATOR_PATTERN to support the feature supported by some LED class drivers.

From the media device perspective such an approach would
be harmful, as the indicator led could be turned on right

before strobing the flash or turning the torch on, by separate calls to different v4l2-flash sub-devices.

The design described above would allow for avoiding issues I touched in the message [1].

Regarding DT documentation:

I would also swap the segments of a property name to follow the convention as in case of "regulator-max-microamp".

Updated version:

==========================================================

Optional properties for child nodes:
- max-microamp : maximum intensity in microamperes of the LED (torch LED for flash devices)
- flash-max-microamp : maximum intensity in microamperes of the flash LED; it is mandatory if the led should support the flash mode
- flash-timeout-microsec : timeout in microseconds after which the flash led is turned off
- indicator-pattern : identifier of the blinking pattern for the indicator led

==========================================================

Regards,
Jacek

[1]
http://permalink.gmane.org/gmane.linux.drivers.video-input-infrastructure/84643

Hi Pavel, Sakari,

Quoted 6 lines · Sakari Ailus

Hi Pavel,

Quoted 3 lines · Pavel Machek

For device tree people: Yes, I know I'll have to create file in documentation, but does the binding below look acceptable?

Quoted 8 lines

Quoted 2 lines

I'll clean up driver code a bit more, remove the printks. Anything else obviously wrong?

Jacek Anaszewski is working on flash support for LED devices. I think it'd be good to sync the DT bindings for the two, as the types of devices supported by the LED API and the V4L2 flash API are quite similar.

Cc Jacek.

I've already submitted a patch [1] that updates leds common bindings. I hasn't been merged yet, as the related LED Flash class patch [2] still needs some indicator leds related discussion [3].

I think this is a good moment to discuss the flash related led common bindings.

[2] http://www.spinics.net/lists/linux-media/msg83100.html