Re: [PATCH v9 0/2] [media] atmel-isc: add driver for Atmel ISC

[Hans Verkuil]

On 08/15/2016 08:09 AM, Wu, Songjun wrote:
> 
> 
> On 8/12/2016 15:32, Hans Verkuil wrote:
>> One quick question:
>>
>> On 08/11/2016 09:06 AM, Songjun Wu wrote:
>>> The Image Sensor Controller driver includes two parts.
>>> 1) Driver code to implement the ISC function.
>>> 2) Device tree binding documentation, it describes how
>>>    to add the ISC in device tree.
>>>
>>> Test result with v4l-utils.
>>> # v4l2-compliance -f
>>> v4l2-compliance SHA   : not available
>>>
>>> Driver Info:
>>>         Driver name   : atmel_isc
>>>         Card type     : Atmel Image Sensor Controller
>>>         Bus info      : platform:atmel_isc f0008000.isc
>>>         Driver version: 4.7.0
>>>         Capabilities  : 0x84200001
>>>                 Video Capture
>>>                 Streaming
>>>                 Extended Pix Format
>>>                 Device Capabilities
>>>         Device Caps   : 0x04200001
>>>                 Video Capture
>>>                 Streaming
>>>                 Extended Pix Format
>>>
>>> Compliance test for device /dev/video0 (not using libv4l2):
>>>
>>> Required ioctls:
>>>         test VIDIOC_QUERYCAP: OK
>>>
>>> Allow for multiple opens:
>>>         test second video open: OK
>>>         test VIDIOC_QUERYCAP: OK
>>>         test VIDIOC_G/S_PRIORITY: OK
>>>         test for unlimited opens: OK
>>>
>>> Debug ioctls:
>>>         test VIDIOC_DBG_G/S_REGISTER: OK (Not Supported)
>>>         test VIDIOC_LOG_STATUS: OK (Not Supported)
>>>
>>> Input ioctls:
>>>         test VIDIOC_G/S_TUNER/ENUM_FREQ_BANDS: OK (Not Supported)
>>>         test VIDIOC_G/S_FREQUENCY: OK (Not Supported)
>>>         test VIDIOC_S_HW_FREQ_SEEK: OK (Not Supported)
>>>         test VIDIOC_ENUMAUDIO: OK (Not Supported)
>>>         test VIDIOC_G/S/ENUMINPUT: OK
>>>         test VIDIOC_G/S_AUDIO: OK (Not Supported)
>>>         Inputs: 1 Audio Inputs: 0 Tuners: 0
>>>
>>> Output ioctls:
>>>         test VIDIOC_G/S_MODULATOR: OK (Not Supported)
>>>         test VIDIOC_G/S_FREQUENCY: OK (Not Supported)
>>>         test VIDIOC_ENUMAUDOUT: OK (Not Supported)
>>>         test VIDIOC_G/S/ENUMOUTPUT: OK (Not Supported)
>>>         test VIDIOC_G/S_AUDOUT: OK (Not Supported)
>>>         Outputs: 0 Audio Outputs: 0 Modulators: 0
>>>
>>> Input/Output configuration ioctls:
>>>         test VIDIOC_ENUM/G/S/QUERY_STD: OK (Not Supported)
>>>         test VIDIOC_ENUM/G/S/QUERY_DV_TIMINGS: OK (Not Supported)
>>>         test VIDIOC_DV_TIMINGS_CAP: OK (Not Supported)
>>>         test VIDIOC_G/S_EDID: OK (Not Supported)
>>>
>>> Test input 0:
>>>
>>>         Control ioctls:
>>>                 test VIDIOC_QUERY_EXT_CTRL/QUERYMENU: OK (Not Supported)
>>>                 test VIDIOC_QUERYCTRL: OK (Not Supported)
>>>                 test VIDIOC_G/S_CTRL: OK (Not Supported)
>>>                 test VIDIOC_G/S/TRY_EXT_CTRLS: OK (Not Supported)
>>>                 test VIDIOC_(UN)SUBSCRIBE_EVENT/DQEVENT: OK (Not Supported)
>>>                 test VIDIOC_G/S_JPEGCOMP: OK (Not Supported)
>>>                 Standard Controls: 0 Private Controls: 0
>>
>> Can you confirm that the sensor subdevice you are using does not have any controls?
>> I ask since that is fairly unusual, so I want to make sure that controls are really
>> not supported in this setup.
>>
> Sorry for the late reply.
> The subdevice I use supports controls, but I did not develop the v4l2 
> controls in the sensor driver.

So you mean the sensor hardware has controls, but the sensor driver doesn't implement
them? Do I understand you correctly?

> Should I add the v4l2 controls and test again?

If the sensor driver does not implement controls (i.e. has a struct v4l2_ctrl_handler),
then everything is fine and the v4l2-compliance output is correct.

Please confirm this. I just want to be 100% certain about this before I make the pull
request.

Thanks,

	Hans