Em Wed, 5 Dec 2018 16:56:39 -0200 Mauro Carvalho Chehab <mchehab+sams...@kernel.org> escreveu:
> Em Fri, 30 Nov 2018 15:58:07 +0100 > Andreas Pape <a...@ca-pape.de> escreveu: > > > Hi Kieran, > > > > thanks for the review. > > > > On Mon, 26 Nov 2018 12:48:08 +0000 > > Kieran Bingham <kieran.bing...@ideasonboard.com> wrote: > > > > > This one worries me a little... (but hopefully not too much) > > > > > > > As mentioned, I don't have any experience concerning video drivers;-). I > > found > > this patch more or less experimentally.... > > > > > > > > > Signed-off-by: Andreas Pape <a...@ca-pape.de> > > > > --- > > > > drivers/media/usb/stkwebcam/stk-webcam.c | 2 ++ > > > > 1 file changed, 2 insertions(+) > > > > > > > > diff --git a/drivers/media/usb/stkwebcam/stk-webcam.c > > > > b/drivers/media/usb/stkwebcam/stk-webcam.c > > > > index e61427e50525..c64928e36a5a 100644 > > > > --- a/drivers/media/usb/stkwebcam/stk-webcam.c > > > > +++ b/drivers/media/usb/stkwebcam/stk-webcam.c > > > > @@ -1155,6 +1155,8 @@ static int stk_vidioc_streamon(struct file *filp, > > > > if (dev->sio_bufs == NULL) > > > > return -EINVAL; > > > > dev->sequence = 0; > > > > + stk_initialise(dev); > > > > + stk_setup_format(dev); > > > > > > Glancing through the code base - this seems to imply to me that s_fmt > > > was not set/called (presumably by cheese) as stk_setup_format() is > > > called only by stk_vidioc_s_fmt_vid_cap() and stk_camera_resume(). > > > > > > Is this an issue? > > > > > > I presume that this means the camera will just operate in a default > > > configuration until cheese chooses something more specific. > > > > > > > Could be. I had a video but colours, sensitivity and possibly other things > > were crap or at least very "psychedelic". Therefore the idea came up that > > some kind of initialisation was missing here. > > > > > Actually - looking further this seems to be the case, as the mode is > > > simply stored in dev->vsettings.mode, and so this last setup stage will > > > just ensure the configuration of the hardware matches the driver. > > > > > > So it seems reasonable to me - but should it be set any earlier? > > > Perhaps not. > > > > > > > > > Are there any complaints when running v4l2-compliance on this device node? > > > > > > > Here is the output of v4l2-compliance: > > > > v4l2-compliance SHA : not available > > > > Driver Info: > > Driver name : stk > > Card type : stk > > Bus info : usb-0000:00:1d.7-5 > > Driver version: 4.15.18 > > Capabilities : 0x85200001 > > Video Capture > > Read/Write > > Streaming > > Extended Pix Format > > Device Capabilities > > Device Caps : 0x05200001 > > Video Capture > > Read/Write > > 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 > > > > 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 > > test VIDIOC_QUERYCTRL: OK > > test VIDIOC_G/S_CTRL: OK > > test VIDIOC_G/S/TRY_EXT_CTRLS: OK > > test VIDIOC_(UN)SUBSCRIBE_EVENT/DQEVENT: OK > > test VIDIOC_G/S_JPEGCOMP: OK (Not Supported) > > Standard Controls: 4 Private Controls: 0 > > > > Format ioctls: > > test VIDIOC_ENUM_FMT/FRAMESIZES/FRAMEINTERVALS: OK > > test VIDIOC_G/S_PARM: OK > > test VIDIOC_G_FBUF: OK (Not Supported) > > test VIDIOC_G_FMT: OK > > warn: v4l2-test-formats.cpp(732): TRY_FMT cannot handle an > > invalid pixelformat. > > warn: v4l2-test-formats.cpp(733): This may or may not be a > > problem. For more information see: > > warn: v4l2-test-formats.cpp(734): > > http://www.mail-archive.com/linux-media@vger.kernel.org/msg56550.html > > test VIDIOC_TRY_FMT: OK > > warn: v4l2-test-formats.cpp(997): S_FMT cannot handle an > > invalid pixelformat. > > warn: v4l2-test-formats.cpp(998): This may or may not be a > > problem. For more information see: > > warn: v4l2-test-formats.cpp(999): > > http://www.mail-archive.com/linux-media@vger.kernel.org/msg56550.html > > test VIDIOC_S_FMT: OK > > test VIDIOC_G_SLICED_VBI_CAP: OK (Not Supported) > > test Cropping: OK (Not Supported) > > test Composing: OK (Not Supported) > > test Scaling: OK (Not Supported) > > > > Codec ioctls: > > test VIDIOC_(TRY_)ENCODER_CMD: OK (Not Supported) > > test VIDIOC_G_ENC_INDEX: OK (Not Supported) > > test VIDIOC_(TRY_)DECODER_CMD: OK (Not Supported) > > > > Buffer ioctls: > > warn: v4l2-test-buffers.cpp(538): VIDIOC_CREATE_BUFS not > > supported > > test VIDIOC_REQBUFS/CREATE_BUFS/QUERYBUF: OK > > test VIDIOC_EXPBUF: OK (Not Supported) > > > > Test input 0: > > > > > > Total: 43, Succeeded: 43, Failed: 0, Warnings: 7 > > I'll apply this patch. On those USB cameras, the best is to always > initialize, as we can't ensure that apps will do that. > > There are actually some record scripts that just do a cat > at the /dev/video0 device, without issuing any ioctl > (or just doing a minimal set of them, via v4l2-ctl). Sorry, misread the patch. It actually seems wrong to initialize it at streamon(). That would actually break things like what I mentioned, where a script first calls v4l2-ctl and then do something like: $ v4l2-ctl -d /dev/video0 -v width=640,height=480,pixelformat=YUY2 $ cat /dev/video0 | mencoder rawvideo -rawvideo w=640:h=480:format=yuy2 (assuming that the stkwebcam driver supports it) I'll drop this one Thanks, Mauro
