[PATCH] media: uvcvideo: Fix uvc_ctrl_fixup_xu_info() not having any effect

[PATCH] media: uvcvideo: Fix uvc_ctrl_fixup_xu_info() not having any effect

[Hans de Goede]

uvc_ctrl_add_info() calls uvc_ctrl_get_flags() which will override
the fixed-up flags set by uvc_ctrl_fixup_xu_info().

This commit fixes this by adding a is_xu argument to uvc_ctrl_add_info()
and skipping the uvc_ctrl_get_flags() call for xu ctrls.

Note that the xu path has already called uvc_ctrl_get_flags() from
uvc_ctrl_fill_xu_info() before calling uvc_ctrl_add_info().

This fixes the xu motor controls not working properly on a Logitech
046d:08cc, and presumably also on the other Logitech models which have
a quirk for this in the uvc_ctrl_fixup_xu_info() function.

Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/media/usb/uvc/uvc_ctrl.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index e399b9fad757..4bdea5814d6a 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1815,7 +1815,7 @@ static int uvc_ctrl_fill_xu_info(struct uvc_device *dev,
 }
 
 static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
-	const struct uvc_control_info *info);
+	const struct uvc_control_info *info, bool is_xu);
 
 static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
 	struct uvc_control *ctrl)
@@ -1830,7 +1830,7 @@ static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
 	if (ret < 0)
 		return ret;
 
-	ret = uvc_ctrl_add_info(dev, ctrl, &info);
+	ret = uvc_ctrl_add_info(dev, ctrl, &info, true);
 	if (ret < 0)
 		uvc_trace(UVC_TRACE_CONTROL, "Failed to initialize control "
 			  "%pUl/%u on device %s entity %u\n", info.entity,
@@ -2009,7 +2009,7 @@ int uvc_ctrl_restore_values(struct uvc_device *dev)
  * Add control information to a given control.
  */
 static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
-	const struct uvc_control_info *info)
+	const struct uvc_control_info *info, bool is_xu)
 {
 	int ret = 0;
 
@@ -2029,7 +2029,8 @@ static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
 	 * default flag values from the uvc_ctrl array when the device doesn't
 	 * properly implement GET_INFO on standard controls.
 	 */
-	uvc_ctrl_get_flags(dev, ctrl, &ctrl->info);
+	if (!is_xu)
+		uvc_ctrl_get_flags(dev, ctrl, &ctrl->info);
 
 	ctrl->initialized = 1;
 
@@ -2252,7 +2253,7 @@ static void uvc_ctrl_init_ctrl(struct uvc_device *dev, struct uvc_control *ctrl)
 	for (; info < iend; ++info) {
 		if (uvc_entity_match_guid(ctrl->entity, info->entity) &&
 		    ctrl->index == info->index) {
-			uvc_ctrl_add_info(dev, ctrl, info);
+			uvc_ctrl_add_info(dev, ctrl, info, false);
 			break;
 		 }
 	}
-- 
2.26.2

Re: [PATCH] media: uvcvideo: Fix uvc_ctrl_fixup_xu_info() not having any effect

[Sasha Levin]

Hi

[This is an automated email]

This commit has been processed because it contains a -stable tag.
The stable tag indicates that it's relevant for the following trees: all

The bot has tested the following trees: v5.7.10, v5.4.53, v4.19.134, v4.14.189, v4.9.231, v4.4.231.

v5.7.10: Build OK!
v5.4.53: Build OK!
v4.19.134: Build OK!
v4.14.189: Failed to apply! Possible dependencies:
    859086ae3636 ("media: uvcvideo: Apply flags from device to actual properties")

v4.9.231: Failed to apply! Possible dependencies:
    859086ae3636 ("media: uvcvideo: Apply flags from device to actual properties")

v4.4.231: Failed to apply! Possible dependencies:
    859086ae3636 ("media: uvcvideo: Apply flags from device to actual properties")


NOTE: The patch will not be queued to stable trees until it is upstream.

How should we proceed with this patch?

-- 
Thanks
Sasha

Re: [PATCH] media: uvcvideo: Fix uvc_ctrl_fixup_xu_info() not having any effect

[Laurent Pinchart]

Hi Hans,

Thank you for the patch.

On Fri, Jul 24, 2020 at 01:48:23PM +0200, Hans de Goede wrote:
> uvc_ctrl_add_info() calls uvc_ctrl_get_flags() which will override
> the fixed-up flags set by uvc_ctrl_fixup_xu_info().
> 
> This commit fixes this by adding a is_xu argument to uvc_ctrl_add_info()
> and skipping the uvc_ctrl_get_flags() call for xu ctrls.
> 
> Note that the xu path has already called uvc_ctrl_get_flags() from
> uvc_ctrl_fill_xu_info() before calling uvc_ctrl_add_info().
> 
> This fixes the xu motor controls not working properly on a Logitech
> 046d:08cc, and presumably also on the other Logitech models which have
> a quirk for this in the uvc_ctrl_fixup_xu_info() function.
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/media/usb/uvc/uvc_ctrl.c | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index e399b9fad757..4bdea5814d6a 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -1815,7 +1815,7 @@ static int uvc_ctrl_fill_xu_info(struct uvc_device *dev,
>  }
>  
>  static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
> -	const struct uvc_control_info *info);
> +	const struct uvc_control_info *info, bool is_xu);
>  
>  static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
>  	struct uvc_control *ctrl)
> @@ -1830,7 +1830,7 @@ static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
>  	if (ret < 0)
>  		return ret;
>  
> -	ret = uvc_ctrl_add_info(dev, ctrl, &info);
> +	ret = uvc_ctrl_add_info(dev, ctrl, &info, true);
>  	if (ret < 0)
>  		uvc_trace(UVC_TRACE_CONTROL, "Failed to initialize control "
>  			  "%pUl/%u on device %s entity %u\n", info.entity,
> @@ -2009,7 +2009,7 @@ int uvc_ctrl_restore_values(struct uvc_device *dev)
>   * Add control information to a given control.
>   */
>  static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
> -	const struct uvc_control_info *info)
> +	const struct uvc_control_info *info, bool is_xu)
>  {
>  	int ret = 0;
>  
> @@ -2029,7 +2029,8 @@ static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
>  	 * default flag values from the uvc_ctrl array when the device doesn't
>  	 * properly implement GET_INFO on standard controls.
>  	 */
> -	uvc_ctrl_get_flags(dev, ctrl, &ctrl->info);
> +	if (!is_xu)
> +		uvc_ctrl_get_flags(dev, ctrl, &ctrl->info);

Would it make sense to instead move this line (and the above comment) to
uvc_ctrl_init_ctrl(), right after the uvc_ctrl_add_info() call ? If you
would prefer keeping it here, I think is_xu should be renamed to
update_flags (with the true/false values switched) to make it clearer.
It would then also add a comment to uvc_ctrl_init_xu_ctrl() right before
the call to uvc_ctrl_add_info() to state that we don't update flags to
avoid overwriting the value set by uvc_ctrl_fixup_xu_info() in
uvc_ctrl_fill_xu_info().

What's your preference ?

>  
>  	ctrl->initialized = 1;
>  
> @@ -2252,7 +2253,7 @@ static void uvc_ctrl_init_ctrl(struct uvc_device *dev, struct uvc_control *ctrl)
>  	for (; info < iend; ++info) {
>  		if (uvc_entity_match_guid(ctrl->entity, info->entity) &&
>  		    ctrl->index == info->index) {
> -			uvc_ctrl_add_info(dev, ctrl, info);
> +			uvc_ctrl_add_info(dev, ctrl, info, false);
>  			break;
>  		 }
>  	}

-- 
Regards,

Laurent Pinchart

Re: [PATCH] media: uvcvideo: Fix uvc_ctrl_fixup_xu_info() not having any effect

[Hans de Goede]

Hi,

On 7/28/20 12:25 AM, Laurent Pinchart wrote:
> Hi Hans,
> 
> Thank you for the patch.
> 
> On Fri, Jul 24, 2020 at 01:48:23PM +0200, Hans de Goede wrote:
>> uvc_ctrl_add_info() calls uvc_ctrl_get_flags() which will override
>> the fixed-up flags set by uvc_ctrl_fixup_xu_info().
>>
>> This commit fixes this by adding a is_xu argument to uvc_ctrl_add_info()
>> and skipping the uvc_ctrl_get_flags() call for xu ctrls.
>>
>> Note that the xu path has already called uvc_ctrl_get_flags() from
>> uvc_ctrl_fill_xu_info() before calling uvc_ctrl_add_info().
>>
>> This fixes the xu motor controls not working properly on a Logitech
>> 046d:08cc, and presumably also on the other Logitech models which have
>> a quirk for this in the uvc_ctrl_fixup_xu_info() function.
>>
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>>   drivers/media/usb/uvc/uvc_ctrl.c | 11 ++++++-----
>>   1 file changed, 6 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
>> index e399b9fad757..4bdea5814d6a 100644
>> --- a/drivers/media/usb/uvc/uvc_ctrl.c
>> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
>> @@ -1815,7 +1815,7 @@ static int uvc_ctrl_fill_xu_info(struct uvc_device *dev,
>>   }
>>   
>>   static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
>> -	const struct uvc_control_info *info);
>> +	const struct uvc_control_info *info, bool is_xu);
>>   
>>   static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
>>   	struct uvc_control *ctrl)
>> @@ -1830,7 +1830,7 @@ static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
>>   	if (ret < 0)
>>   		return ret;
>>   
>> -	ret = uvc_ctrl_add_info(dev, ctrl, &info);
>> +	ret = uvc_ctrl_add_info(dev, ctrl, &info, true);
>>   	if (ret < 0)
>>   		uvc_trace(UVC_TRACE_CONTROL, "Failed to initialize control "
>>   			  "%pUl/%u on device %s entity %u\n", info.entity,
>> @@ -2009,7 +2009,7 @@ int uvc_ctrl_restore_values(struct uvc_device *dev)
>>    * Add control information to a given control.
>>    */
>>   static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
>> -	const struct uvc_control_info *info)
>> +	const struct uvc_control_info *info, bool is_xu)
>>   {
>>   	int ret = 0;
>>   
>> @@ -2029,7 +2029,8 @@ static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
>>   	 * default flag values from the uvc_ctrl array when the device doesn't
>>   	 * properly implement GET_INFO on standard controls.
>>   	 */
>> -	uvc_ctrl_get_flags(dev, ctrl, &ctrl->info);
>> +	if (!is_xu)
>> +		uvc_ctrl_get_flags(dev, ctrl, &ctrl->info);
> 
> Would it make sense to instead move this line (and the above comment) to
> uvc_ctrl_init_ctrl(), right after the uvc_ctrl_add_info() call ?

I was thinking about the same lines, since that seems like the
obvious / logical fix. I was thinking about doing it before the
uvc_ctrl_add_info() call, but that will not work, because info
is const before the call.

Doing it after the add_info() call, as you suggest, we can pass
&ctrl->info to the get_flags call. So yes that will work and
is the logical thing to do.

I'll spin a v2 with this change.

> If you
> would prefer keeping it here, I think is_xu should be renamed to
> update_flags (with the true/false values switched) to make it clearer.
> It would then also add a comment to uvc_ctrl_init_xu_ctrl() right before
> the call to uvc_ctrl_add_info() to state that we don't update flags to
> avoid overwriting the value set by uvc_ctrl_fixup_xu_info() in
> uvc_ctrl_fill_xu_info().
> 
> What's your preference ?

See above.

Regards,

Hans



> 
>>   
>>   	ctrl->initialized = 1;
>>   
>> @@ -2252,7 +2253,7 @@ static void uvc_ctrl_init_ctrl(struct uvc_device *dev, struct uvc_control *ctrl)
>>   	for (; info < iend; ++info) {
>>   		if (uvc_entity_match_guid(ctrl->entity, info->entity) &&
>>   		    ctrl->index == info->index) {
>> -			uvc_ctrl_add_info(dev, ctrl, info);
>> +			uvc_ctrl_add_info(dev, ctrl, info, false);
>>   			break;
>>   		 }
>>   	}
>