| Message ID | 4b1bc0d5-808b-816d-d7de-5baa8851e74f@xs4all.nl |
|---|---|
| State | New |
| Headers | show |
| Series | media: usb: uvc: fill in description for unknown pixelformats | expand |
On 29/03/2023 18:05, Ricardo Ribalda wrote: > Hi Hans > > Thanks for the patch. > > I believe the user can fetch this info from lsusb, so this is kind of > duplicated info, and this is why it was removed. You got to set some description, so using the GUID this seems best. > Is there an app that uses this unknown format code ? Or the only > complaint is that WARN() is too loud for the user? Normally drivers do not pass on unknown formats, but if a driver does, then I want a WARN. If a driver does this legitimately (and I understand that's the case for UVC), then the driver should fill in the description to avoid this WARN. > > Regards! > > On Wed, 29 Mar 2023 at 14:39, Hans Verkuil <hverkuil@xs4all.nl> wrote: >> >> If the fcc is 0 (indicating an unknown GUID format), then fill in the >> description field in ENUM_FMT. Otherwise the V4L2 core will WARN. >> >> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> >> Fixes: 50459f103edf ("media: uvcvideo: Remove format descriptions") >> --- >> diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c >> index 7aefa76a42b3..2f1ced1212cd 100644 >> --- a/drivers/media/usb/uvc/uvc_driver.c >> +++ b/drivers/media/usb/uvc/uvc_driver.c >> @@ -256,6 +256,9 @@ static int uvc_parse_format(struct uvc_device *dev, >> } else { >> dev_info(&streaming->intf->dev, >> "Unknown video format %pUl\n", &buffer[5]); >> + snprintf(format->name, sizeof(format->name), "%pUl\n", >> + &buffer[5]); > Don't we need at least 38 chars for this? Yes. But all we have is 31 chars, so we take what we can :-) This is what uvc did before this was removed. Regards, Hans > > https://docs.kernel.org/core-api/printk-formats.html#uuid-guid-addresses > > >> + >> format->fcc = 0; >> } >> >> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c >> index 35453f81c1d9..fc6f9e7d8506 100644 >> --- a/drivers/media/usb/uvc/uvc_v4l2.c >> +++ b/drivers/media/usb/uvc/uvc_v4l2.c >> @@ -713,6 +713,10 @@ static int uvc_ioctl_enum_fmt(struct uvc_streaming *stream, >> if (format->flags & UVC_FMT_FLAG_COMPRESSED) >> fmt->flags |= V4L2_FMT_FLAG_COMPRESSED; >> fmt->pixelformat = format->fcc; >> + if (format->name[0]) >> + strscpy(fmt->description, format->name, >> + sizeof(fmt->description)); >> + >> return 0; >> } >> >> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h >> index 9a596c8d894a..22656755a801 100644 >> --- a/drivers/media/usb/uvc/uvcvideo.h >> +++ b/drivers/media/usb/uvc/uvcvideo.h >> @@ -264,6 +264,8 @@ struct uvc_format { >> u32 fcc; >> u32 flags; >> >> + char name[32]; >> + >> unsigned int nframes; >> struct uvc_frame *frame; >> }; >> > > > -- > Ricardo Ribalda
Hi, On 3/29/23 14:28, Hans Verkuil wrote: > If the fcc is 0 (indicating an unknown GUID format), then fill in the > description field in ENUM_FMT. Otherwise the V4L2 core will WARN. > > Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> > Fixes: 50459f103edf ("media: uvcvideo: Remove format descriptions") Thanks, patch looks good to me: FWIW: Reviewed-by: Hans de Goede <hdegoede@redhat.com> Regards, Hans > --- > diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c > index 7aefa76a42b3..2f1ced1212cd 100644 > --- a/drivers/media/usb/uvc/uvc_driver.c > +++ b/drivers/media/usb/uvc/uvc_driver.c > @@ -256,6 +256,9 @@ static int uvc_parse_format(struct uvc_device *dev, > } else { > dev_info(&streaming->intf->dev, > "Unknown video format %pUl\n", &buffer[5]); > + snprintf(format->name, sizeof(format->name), "%pUl\n", > + &buffer[5]); > + > format->fcc = 0; > } > > diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c > index 35453f81c1d9..fc6f9e7d8506 100644 > --- a/drivers/media/usb/uvc/uvc_v4l2.c > +++ b/drivers/media/usb/uvc/uvc_v4l2.c > @@ -713,6 +713,10 @@ static int uvc_ioctl_enum_fmt(struct uvc_streaming *stream, > if (format->flags & UVC_FMT_FLAG_COMPRESSED) > fmt->flags |= V4L2_FMT_FLAG_COMPRESSED; > fmt->pixelformat = format->fcc; > + if (format->name[0]) > + strscpy(fmt->description, format->name, > + sizeof(fmt->description)); > + > return 0; > } > > diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h > index 9a596c8d894a..22656755a801 100644 > --- a/drivers/media/usb/uvc/uvcvideo.h > +++ b/drivers/media/usb/uvc/uvcvideo.h > @@ -264,6 +264,8 @@ struct uvc_format { > u32 fcc; > u32 flags; > > + char name[32]; > + > unsigned int nframes; > struct uvc_frame *frame; > }; >
Hi Hans, On Wed, Apr 05, 2023 at 09:40:20AM +0300, Laurent Pinchart wrote: > On Wed, Mar 29, 2023 at 07:20:59PM +0200, Hans Verkuil wrote: > > On 29/03/2023 18:05, Ricardo Ribalda wrote: > > > Hi Hans > > > > > > Thanks for the patch. > > > > > > I believe the user can fetch this info from lsusb, so this is kind of > > > duplicated info, and this is why it was removed. > > > > You got to set some description, so using the GUID this seems best. > > > > > Is there an app that uses this unknown format code ? Or the only > > > complaint is that WARN() is too loud for the user? > > > > Normally drivers do not pass on unknown formats, but if a driver does, > > then I want a WARN. If a driver does this legitimately (and I understand > > that's the case for UVC), then the driver should fill in the description > > to avoid this WARN. > > In hindsight we shouldn't have added a text description to formats :-) > > > > On Wed, 29 Mar 2023 at 14:39, Hans Verkuil wrote: > > >> > > >> If the fcc is 0 (indicating an unknown GUID format), then fill in the > > >> description field in ENUM_FMT. Otherwise the V4L2 core will WARN. > > >> > > >> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> > > >> Fixes: 50459f103edf ("media: uvcvideo: Remove format descriptions") > > >> --- > > >> diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c > > >> index 7aefa76a42b3..2f1ced1212cd 100644 > > >> --- a/drivers/media/usb/uvc/uvc_driver.c > > >> +++ b/drivers/media/usb/uvc/uvc_driver.c > > >> @@ -256,6 +256,9 @@ static int uvc_parse_format(struct uvc_device *dev, > > >> } else { > > >> dev_info(&streaming->intf->dev, > > >> "Unknown video format %pUl\n", &buffer[5]); > > >> + snprintf(format->name, sizeof(format->name), "%pUl\n", > > >> + &buffer[5]); > > > Don't we need at least 38 chars for this? > > > > Yes. But all we have is 31 chars, so we take what we can :-) > > > > This is what uvc did before this was removed. > > > > Regards, > > > > Hans > > > > > https://docs.kernel.org/core-api/printk-formats.html#uuid-guid-addresses > > > > > >> + > > >> format->fcc = 0; > > >> } > > >> > > >> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c > > >> index 35453f81c1d9..fc6f9e7d8506 100644 > > >> --- a/drivers/media/usb/uvc/uvc_v4l2.c > > >> +++ b/drivers/media/usb/uvc/uvc_v4l2.c > > >> @@ -713,6 +713,10 @@ static int uvc_ioctl_enum_fmt(struct uvc_streaming *stream, > > >> if (format->flags & UVC_FMT_FLAG_COMPRESSED) > > >> fmt->flags |= V4L2_FMT_FLAG_COMPRESSED; > > >> fmt->pixelformat = format->fcc; > > >> + if (format->name[0]) > > >> + strscpy(fmt->description, format->name, > > >> + sizeof(fmt->description)); > > >> + > > >> return 0; > > >> } > > >> > > >> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h > > >> index 9a596c8d894a..22656755a801 100644 > > >> --- a/drivers/media/usb/uvc/uvcvideo.h > > >> +++ b/drivers/media/usb/uvc/uvcvideo.h > > >> @@ -264,6 +264,8 @@ struct uvc_format { > > >> u32 fcc; > > >> u32 flags; > > >> > > >> + char name[32]; > > >> + > > I'd not really nice to have to store the name for every format, when we > know it will very rarely be used. > > One alternative option would be to store the GUID, which would halve the > amount of memory. Another option would be to stop reporting those > formats to userspace in uvc_ioctl_enum_fmt(). They can't be selected > anyway, they have no unique 4CC. Any opinion on this ? I'm increasingly tempted by not reporting unsupported formats to userspace. > > >> unsigned int nframes; > > >> struct uvc_frame *frame; > > >> };
On 19/04/2023 08:23, Laurent Pinchart wrote: > Hi Hans, > > On Wed, Apr 05, 2023 at 09:40:20AM +0300, Laurent Pinchart wrote: >> On Wed, Mar 29, 2023 at 07:20:59PM +0200, Hans Verkuil wrote: >>> On 29/03/2023 18:05, Ricardo Ribalda wrote: >>>> Hi Hans >>>> >>>> Thanks for the patch. >>>> >>>> I believe the user can fetch this info from lsusb, so this is kind of >>>> duplicated info, and this is why it was removed. >>> >>> You got to set some description, so using the GUID this seems best. >>> >>>> Is there an app that uses this unknown format code ? Or the only >>>> complaint is that WARN() is too loud for the user? >>> >>> Normally drivers do not pass on unknown formats, but if a driver does, >>> then I want a WARN. If a driver does this legitimately (and I understand >>> that's the case for UVC), then the driver should fill in the description >>> to avoid this WARN. >> >> In hindsight we shouldn't have added a text description to formats :-) >> >>>> On Wed, 29 Mar 2023 at 14:39, Hans Verkuil wrote: >>>>> >>>>> If the fcc is 0 (indicating an unknown GUID format), then fill in the >>>>> description field in ENUM_FMT. Otherwise the V4L2 core will WARN. >>>>> >>>>> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> >>>>> Fixes: 50459f103edf ("media: uvcvideo: Remove format descriptions") >>>>> --- >>>>> diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c >>>>> index 7aefa76a42b3..2f1ced1212cd 100644 >>>>> --- a/drivers/media/usb/uvc/uvc_driver.c >>>>> +++ b/drivers/media/usb/uvc/uvc_driver.c >>>>> @@ -256,6 +256,9 @@ static int uvc_parse_format(struct uvc_device *dev, >>>>> } else { >>>>> dev_info(&streaming->intf->dev, >>>>> "Unknown video format %pUl\n", &buffer[5]); >>>>> + snprintf(format->name, sizeof(format->name), "%pUl\n", >>>>> + &buffer[5]); >>>> Don't we need at least 38 chars for this? >>> >>> Yes. But all we have is 31 chars, so we take what we can :-) >>> >>> This is what uvc did before this was removed. >>> >>> Regards, >>> >>> Hans >>> >>>> https://docs.kernel.org/core-api/printk-formats.html#uuid-guid-addresses >>>> >>>>> + >>>>> format->fcc = 0; >>>>> } >>>>> >>>>> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c >>>>> index 35453f81c1d9..fc6f9e7d8506 100644 >>>>> --- a/drivers/media/usb/uvc/uvc_v4l2.c >>>>> +++ b/drivers/media/usb/uvc/uvc_v4l2.c >>>>> @@ -713,6 +713,10 @@ static int uvc_ioctl_enum_fmt(struct uvc_streaming *stream, >>>>> if (format->flags & UVC_FMT_FLAG_COMPRESSED) >>>>> fmt->flags |= V4L2_FMT_FLAG_COMPRESSED; >>>>> fmt->pixelformat = format->fcc; >>>>> + if (format->name[0]) >>>>> + strscpy(fmt->description, format->name, >>>>> + sizeof(fmt->description)); >>>>> + >>>>> return 0; >>>>> } >>>>> >>>>> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h >>>>> index 9a596c8d894a..22656755a801 100644 >>>>> --- a/drivers/media/usb/uvc/uvcvideo.h >>>>> +++ b/drivers/media/usb/uvc/uvcvideo.h >>>>> @@ -264,6 +264,8 @@ struct uvc_format { >>>>> u32 fcc; >>>>> u32 flags; >>>>> >>>>> + char name[32]; >>>>> + >> >> I'd not really nice to have to store the name for every format, when we >> know it will very rarely be used. >> >> One alternative option would be to store the GUID, which would halve the >> amount of memory. Another option would be to stop reporting those >> formats to userspace in uvc_ioctl_enum_fmt(). They can't be selected >> anyway, they have no unique 4CC. > > Any opinion on this ? I'm increasingly tempted by not reporting > unsupported formats to userspace. Since they cannot be selected, I think that is the best approach. Perhaps only show them in the kernel log if debugging is enabled. Regards, Hans > >>>>> unsigned int nframes; >>>>> struct uvc_frame *frame; >>>>> }; >
On 29.03.23 14:28, Hans Verkuil wrote: > If the fcc is 0 (indicating an unknown GUID format), then fill in the > description field in ENUM_FMT. Otherwise the V4L2 core will WARN. What happened to this? It seems this fall through the cracks. BTW: > Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Afaics it might be good to have these in here: Link: https://bugzilla.kernel.org/show_bug.cgi?id=217252 Link: https://bugzilla.redhat.com/show_bug.cgi?id=2180107 A comment in the former is what brought me here. Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) -- Everything you wanna know about Linux kernel regression tracking: https://linux-regtracking.leemhuis.info/about/#tldr If I did something stupid, please tell me, as explained on that page. #regzbot ^backmonitor: https://lore.kernel.org/lkml/dc8e5276-ef88-648f-9f0d-10151ea62c90@leemhuis.info/ #regzbot poke > Fixes: 50459f103edf ("media: uvcvideo: Remove format descriptions") > --- > diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c > index 7aefa76a42b3..2f1ced1212cd 100644 > --- a/drivers/media/usb/uvc/uvc_driver.c > +++ b/drivers/media/usb/uvc/uvc_driver.c > @@ -256,6 +256,9 @@ static int uvc_parse_format(struct uvc_device *dev, > } else { > dev_info(&streaming->intf->dev, > "Unknown video format %pUl\n", &buffer[5]); > + snprintf(format->name, sizeof(format->name), "%pUl\n", > + &buffer[5]); > + > format->fcc = 0; > } > > diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c > index 35453f81c1d9..fc6f9e7d8506 100644 > --- a/drivers/media/usb/uvc/uvc_v4l2.c > +++ b/drivers/media/usb/uvc/uvc_v4l2.c > @@ -713,6 +713,10 @@ static int uvc_ioctl_enum_fmt(struct uvc_streaming *stream, > if (format->flags & UVC_FMT_FLAG_COMPRESSED) > fmt->flags |= V4L2_FMT_FLAG_COMPRESSED; > fmt->pixelformat = format->fcc; > + if (format->name[0]) > + strscpy(fmt->description, format->name, > + sizeof(fmt->description)); > + > return 0; > } > > diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h > index 9a596c8d894a..22656755a801 100644 > --- a/drivers/media/usb/uvc/uvcvideo.h > +++ b/drivers/media/usb/uvc/uvcvideo.h > @@ -264,6 +264,8 @@ struct uvc_format { > u32 fcc; > u32 flags; > > + char name[32]; > + > unsigned int nframes; > struct uvc_frame *frame; > }; >
On 31.05.23 14:44, Laurent Pinchart wrote: > Hi Thorsten, > > On Wed, May 31, 2023 at 01:48:51PM +0200, Linux regression tracking (Thorsten Leemhuis) wrote: >> On 29.03.23 14:28, Hans Verkuil wrote: >>> If the fcc is 0 (indicating an unknown GUID format), then fill in the >>> description field in ENUM_FMT. Otherwise the V4L2 core will WARN. >> >> What happened to this? It seems this fall through the cracks. > > I've posted a better fix, You mean an even better fix, as this one already was a better fix for a earlier fix ;) > see > https://lore.kernel.org/linux-media/20230506065809.24645-1-laurent.pinchart@ideasonboard.com/. > Of course, fate had it that it got reviewed exactly on the day when I started by holidays :-S :-D > I'm now back, and will send a pull request. In that case: welcome back. >> BTW: >> >>> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> >> >> Afaics it might be good to have these in here: >> >> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217252 >> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2180107 > > I'll add those two links. Great, many thx! Ciao, Thorsten >> A comment in the former is what brought me here. >> >> Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) >> -- >> Everything you wanna know about Linux kernel regression tracking: >> https://linux-regtracking.leemhuis.info/about/#tldr >> If I did something stupid, please tell me, as explained on that page. >> >> #regzbot ^backmonitor: >> https://lore.kernel.org/lkml/dc8e5276-ef88-648f-9f0d-10151ea62c90@leemhuis.info/ >> #regzbot poke >> >>> Fixes: 50459f103edf ("media: uvcvideo: Remove format descriptions") >>> --- >>> diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c >>> index 7aefa76a42b3..2f1ced1212cd 100644 >>> --- a/drivers/media/usb/uvc/uvc_driver.c >>> +++ b/drivers/media/usb/uvc/uvc_driver.c >>> @@ -256,6 +256,9 @@ static int uvc_parse_format(struct uvc_device *dev, >>> } else { >>> dev_info(&streaming->intf->dev, >>> "Unknown video format %pUl\n", &buffer[5]); >>> + snprintf(format->name, sizeof(format->name), "%pUl\n", >>> + &buffer[5]); >>> + >>> format->fcc = 0; >>> } >>> >>> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c >>> index 35453f81c1d9..fc6f9e7d8506 100644 >>> --- a/drivers/media/usb/uvc/uvc_v4l2.c >>> +++ b/drivers/media/usb/uvc/uvc_v4l2.c >>> @@ -713,6 +713,10 @@ static int uvc_ioctl_enum_fmt(struct uvc_streaming *stream, >>> if (format->flags & UVC_FMT_FLAG_COMPRESSED) >>> fmt->flags |= V4L2_FMT_FLAG_COMPRESSED; >>> fmt->pixelformat = format->fcc; >>> + if (format->name[0]) >>> + strscpy(fmt->description, format->name, >>> + sizeof(fmt->description)); >>> + >>> return 0; >>> } >>> >>> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h >>> index 9a596c8d894a..22656755a801 100644 >>> --- a/drivers/media/usb/uvc/uvcvideo.h >>> +++ b/drivers/media/usb/uvc/uvcvideo.h >>> @@ -264,6 +264,8 @@ struct uvc_format { >>> u32 fcc; >>> u32 flags; >>> >>> + char name[32]; >>> + >>> unsigned int nframes; >>> struct uvc_frame *frame; >>> }; >
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c index 7aefa76a42b3..2f1ced1212cd 100644 --- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -256,6 +256,9 @@ static int uvc_parse_format(struct uvc_device *dev, } else { dev_info(&streaming->intf->dev, "Unknown video format %pUl\n", &buffer[5]); + snprintf(format->name, sizeof(format->name), "%pUl\n", + &buffer[5]); + format->fcc = 0; } diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c index 35453f81c1d9..fc6f9e7d8506 100644 --- a/drivers/media/usb/uvc/uvc_v4l2.c +++ b/drivers/media/usb/uvc/uvc_v4l2.c @@ -713,6 +713,10 @@ static int uvc_ioctl_enum_fmt(struct uvc_streaming *stream, if (format->flags & UVC_FMT_FLAG_COMPRESSED) fmt->flags |= V4L2_FMT_FLAG_COMPRESSED; fmt->pixelformat = format->fcc; + if (format->name[0]) + strscpy(fmt->description, format->name, + sizeof(fmt->description)); + return 0; } diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h index 9a596c8d894a..22656755a801 100644 --- a/drivers/media/usb/uvc/uvcvideo.h +++ b/drivers/media/usb/uvc/uvcvideo.h @@ -264,6 +264,8 @@ struct uvc_format { u32 fcc; u32 flags; + char name[32]; + unsigned int nframes; struct uvc_frame *frame; };
If the fcc is 0 (indicating an unknown GUID format), then fill in the description field in ENUM_FMT. Otherwise the V4L2 core will WARN. Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Fixes: 50459f103edf ("media: uvcvideo: Remove format descriptions") ---