Re: [PATCH 00/14] Remove linux/version.h from most drivers/media

From: Hans Verkuil
Date: Sun Jun 26 2011 - 14:01:08 EST

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In reply to: Mauro Carvalho Chehab: "[PATCH 00/14] Remove linux/version.h from most drivers/media"
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On Sunday, June 26, 2011 18:06:20 Mauro Carvalho Chehab wrote:
> At the V4L2 API, one of the fields of VIDIOC_QUERYCAP requires the usage
> of KERNEL_VERSION macro, in order to provide the driver version. However,
> this is not handled consistently across subsystems. There are very few
> drivers that take it seriously.
>
> So, instead of the current way, let's replace it by a subsystem version.
> Removing the driver-specific version reported via V4L2 API is a good
> thing, due to several reasons:
> 1) every time include/linux/version.h changes, all media drivers
> need to be recompiled;
> 2) eventually, this macro will be changed at Kernel 3.x;
> 3) developers are lazy on updating it at a per-driver basis;
> The information there is not consistent;
> 4) a check for the V4L2 API, incremented as new changes are added
> means that the changes will happen on a consistent way, being
> incremented when new features are added at the Kernel;
> 5) From time to time, people do the wrong thing, including version.h
> where it is not needed, and spending Kernel Janitor's time to
> cleanup the mess.
>
> There's one additional reason for the change: before this patch series,
> a call to an unsupported ioctl would be returning -EINVAL. So, userspace
> applications can't detect if the error were due to invalid parameters,
> or to unsupported ioctl. This series changes the behavior to return
> -ENOIOCTLCMD for non-supported ioctl's.
>
> So, after this patch series, if VIDIOC_QUERYCAP returns version 3.x.y,
> userspace applications can rely on -ENOIOCTLCMD in order to detect that
> an ioctl is not supported by a given driver.
>
> After this patch series, the only places at drivers/media that will keep
> linux/version.h are:
> drivers/media/video/et61x251/et61x251_core.c
> drivers/media/video/pvrusb2/pvrusb2-v4l2.c
> drivers/media/video/sn9c102/sn9c102_core.c
> drivers/media/video/uvc/uvc_driver.c
> drivers/media/video/uvc/uvc_v4l2.c
> And, of course: drivers/media/video/v4l2-ioctl.c
>
> The rationale is that et61x251, pvrusb2, sn9c102 and uvc uses the
> legacy way of handling ioctl's. Two of those drivers are obsoleted by
> gspca. The other two drivers (pvrusb2 and uvc) needs porting.

Except for the ENOIOCTLCMD changes:

Acked-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>

I suggest that the ENOIOCTLCMD changes are in a separate patch series due to
the uncertainty of what the right return code is.

Also, while it would be great to have a different ioctl than EINVAL for unsupported
ioctls, I am afraid of breaking existing applications. Some may rely on this.

Regards,

Hans

>
> Mauro Carvalho Chehab (14):
> [media] v4l2 core: return -ENOIOCTLCMD if an ioctl doesn't exist
> [media] return -ENOIOCTLCMD for unsupported ioctl's at legacy drivers
> [media] v4l2-ioctl: Add a default value for kernel version
> [media] drxd, siano: Remove unused include linux/version.h
> [media] Stop using linux/version.h on most video drivers
> [media] pwc: Use the default version for VIDIOC_QUERYCAP
> [media] ivtv,cx18: Use default version control for VIDIOC_QUERYCAP
> [media] et61x251: Use LINUX_VERSION_CODE for VIDIOC_QUERYCAP
> [media] pvrusb2: Use LINUX_VERSION_CODE for VIDIOC_QUERYCAP
> [media] sn9c102: Use LINUX_VERSION_CODE for VIDIOC_QUERYCAP
> [media] uvcvideo: Use LINUX_VERSION_CODE for VIDIOC_QUERYCAP
> [media] Stop using linux/version.h the remaining video drivers
> [media] radio: Use the subsystem version control for VIDIOC_QUERYCAP
> [media] DocBook/v4l: Document the new system-wide version behavior
>
> Documentation/DocBook/media/Makefile | 1 +
> Documentation/DocBook/media/v4l/common.xml | 10 ++++++++-
> Documentation/DocBook/media/v4l/func-ioctl.xml | 17 ++++++++-------
> Documentation/DocBook/media/v4l/v4l2.xml | 7 ++++++
> .../DocBook/media/v4l/vidioc-querycap.xml | 15 ++++++++-----
> drivers/media/dvb/frontends/drxd_hard.c | 1 -
> drivers/media/dvb/siano/smscoreapi.h | 1 -
> drivers/media/radio/dsbr100.c | 7 +----
> drivers/media/radio/radio-aimslab.c | 5 +---
> drivers/media/radio/radio-aztech.c | 5 +---
> drivers/media/radio/radio-cadet.c | 5 +---
> drivers/media/radio/radio-gemtek.c | 7 +----
> drivers/media/radio/radio-maxiradio.c | 10 +++-----
> drivers/media/radio/radio-mr800.c | 6 +---
> drivers/media/radio/radio-rtrack2.c | 5 +---
> drivers/media/radio/radio-sf16fmi.c | 5 +---
> drivers/media/radio/radio-tea5764.c | 6 +---
> drivers/media/radio/radio-terratec.c | 5 +---
> drivers/media/radio/radio-timb.c | 3 +-
> drivers/media/radio/radio-trust.c | 5 +---
> drivers/media/radio/radio-typhoon.c | 9 +++----
> drivers/media/radio/radio-zoltrix.c | 5 +---
> drivers/media/radio/si470x/radio-si470x-i2c.c | 4 +--
> drivers/media/radio/si470x/radio-si470x-usb.c | 2 -
> drivers/media/radio/si470x/radio-si470x.h | 1 -
> drivers/media/radio/wl128x/fmdrv.h | 5 +---
> drivers/media/radio/wl128x/fmdrv_v4l2.c | 1 -
> drivers/media/video/arv.c | 5 +--
> drivers/media/video/au0828/au0828-core.c | 1 +
> drivers/media/video/au0828/au0828-video.c | 5 ----
> drivers/media/video/bt8xx/bttv-driver.c | 14 +++---------
> drivers/media/video/bt8xx/bttvp.h | 3 --
> drivers/media/video/bw-qcam.c | 3 +-
> drivers/media/video/c-qcam.c | 3 +-
> drivers/media/video/cpia2/cpia2.h | 5 ----
> drivers/media/video/cpia2/cpia2_v4l.c | 12 +++-------
> drivers/media/video/cx18/cx18-driver.h | 1 -
> drivers/media/video/cx18/cx18-ioctl.c | 1 -
> drivers/media/video/cx18/cx18-version.h | 8 +------
> drivers/media/video/cx231xx/cx231xx-video.c | 14 +++---------
> drivers/media/video/cx231xx/cx231xx.h | 1 -
> drivers/media/video/cx23885/altera-ci.c | 1 -
> drivers/media/video/cx23885/cx23885-417.c | 1 -
> drivers/media/video/cx23885/cx23885-core.c | 13 ++---------
> drivers/media/video/cx23885/cx23885-video.c | 1 -
> drivers/media/video/cx23885/cx23885.h | 3 +-
> drivers/media/video/cx88/cx88-alsa.c | 19 +++--------------
> drivers/media/video/cx88/cx88-blackbird.c | 20 ++----------------
> drivers/media/video/cx88/cx88-dvb.c | 18 ++--------------
> drivers/media/video/cx88/cx88-mpeg.c | 11 ++-------
> drivers/media/video/cx88/cx88-video.c | 21 ++-----------------
> drivers/media/video/cx88/cx88.h | 4 +-
> drivers/media/video/davinci/vpif_capture.c | 9 ++-----
> drivers/media/video/davinci/vpif_capture.h | 7 +-----
> drivers/media/video/davinci/vpif_display.c | 9 ++-----
> drivers/media/video/davinci/vpif_display.h | 8 +------
> drivers/media/video/em28xx/em28xx-video.c | 14 ++++--------
> drivers/media/video/et61x251/et61x251.h | 1 -
> drivers/media/video/et61x251/et61x251_core.c | 16 +++-----------
> drivers/media/video/fsl-viu.c | 10 +-------
> drivers/media/video/gspca/gl860/gl860.h | 1 -
> drivers/media/video/gspca/gspca.c | 12 +++-------
> drivers/media/video/hdpvr/hdpvr-core.c | 1 +
> drivers/media/video/hdpvr/hdpvr-video.c | 2 -
> drivers/media/video/hdpvr/hdpvr.h | 6 -----
> drivers/media/video/ivtv/ivtv-driver.h | 1 -
> drivers/media/video/ivtv/ivtv-ioctl.c | 1 -
> drivers/media/video/ivtv/ivtv-version.h | 7 +-----
> drivers/media/video/m5mols/m5mols_capture.c | 2 -
> drivers/media/video/m5mols/m5mols_core.c | 1 -
> drivers/media/video/mem2mem_testdev.c | 4 +--
> drivers/media/video/mx1_camera.c | 5 +--
> drivers/media/video/mx2_camera.c | 5 +--
> drivers/media/video/mx3_camera.c | 3 +-
> drivers/media/video/omap1_camera.c | 5 +--
> drivers/media/video/omap24xxcam.c | 5 +--
> drivers/media/video/omap3isp/isp.c | 1 +
> drivers/media/video/omap3isp/ispvideo.c | 1 -
> drivers/media/video/omap3isp/ispvideo.h | 3 +-
> drivers/media/video/pms.c | 4 +--
> drivers/media/video/pvrusb2/pvrusb2-main.c | 1 +
> drivers/media/video/pvrusb2/pvrusb2-v4l2.c | 9 +------
> drivers/media/video/pwc/pwc-ioctl.h | 1 -
> drivers/media/video/pwc/pwc-v4l.c | 1 -
> drivers/media/video/pwc/pwc.h | 7 +-----
> drivers/media/video/pxa_camera.c | 5 +--
> drivers/media/video/s2255drv.c | 15 +++----------
> drivers/media/video/s5p-fimc/fimc-capture.c | 2 -
> drivers/media/video/s5p-fimc/fimc-core.c | 3 +-
> drivers/media/video/saa7134/saa7134-core.c | 12 +++-------
> drivers/media/video/saa7134/saa7134-empress.c | 1 -
> drivers/media/video/saa7134/saa7134-video.c | 2 -
> drivers/media/video/saa7134/saa7134.h | 3 +-
> drivers/media/video/saa7164/saa7164.h | 1 -
> drivers/media/video/sh_mobile_ceu_camera.c | 3 +-
> drivers/media/video/sh_vou.c | 3 +-
> drivers/media/video/sn9c102/sn9c102.h | 1 -
> drivers/media/video/sn9c102/sn9c102_core.c | 16 +++-----------
> drivers/media/video/timblogiw.c | 1 -
> drivers/media/video/tlg2300/pd-common.h | 1 -
> drivers/media/video/tlg2300/pd-main.c | 1 +
> drivers/media/video/tlg2300/pd-radio.c | 2 -
> drivers/media/video/usbvision/usbvision-video.c | 12 +----------
> drivers/media/video/uvc/uvc_driver.c | 3 +-
> drivers/media/video/uvc/uvc_v4l2.c | 4 +-
> drivers/media/video/uvc/uvcvideo.h | 3 +-
> drivers/media/video/v4l2-ioctl.c | 6 +++-
> drivers/media/video/vino.c | 5 +---
> drivers/media/video/vivi.c | 14 +++---------
> drivers/media/video/w9966.c | 4 +--
> drivers/media/video/zoran/zoran.h | 4 ---
> drivers/media/video/zoran/zoran_card.c | 7 ++++-
> drivers/media/video/zoran/zoran_driver.c | 3 --
> drivers/media/video/zr364xx.c | 6 +---
> 114 files changed, 186 insertions(+), 461 deletions(-)
>
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Next message: Will Drewry: "Re: [PATCH v2] init: add root=PARTUUID=UUID,PARTNROFF=%d support"
Previous message: Marc MERLIN: "All kinds of irq 16: nobody cared with Sandy Bridge Asus P8H67-MMB and multiple drivers"
In reply to: Mauro Carvalho Chehab: "[PATCH 00/14] Remove linux/version.h from most drivers/media"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]