From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mout.kundenserver.de ([212.227.126.131]:37073 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726563AbeLACHq (ORCPT ); Fri, 30 Nov 2018 21:07:46 -0500 Date: Fri, 30 Nov 2018 15:58:07 +0100 From: Andreas Pape To: kieran.bingham@ideasonboard.com Cc: linux-media@vger.kernel.org Subject: Re: [PATCH 2/3] media: stkwebcam: Bugfix for not correctly initialized camera Message-Id: <20181130155807.f1be928e4fc3a05e13fc710b@ca-pape.de> In-Reply-To: References: <20181123161454.3215-1-ap@ca-pape.de> <20181123161454.3215-3-ap@ca-pape.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Hi Kieran, thanks for the review. On Mon, 26 Nov 2018 12:48:08 +0000 Kieran Bingham 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 > > --- > > 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 Kind regards, Andreas -- Andreas Pape