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  1. 14 5月, 2012 1 次提交
    • S
      [media] v4l2: use __u32 rather than enums in ioctl() structs · 6016af82
      由 Sakari Ailus 提交于 
      V4L2 uses the enum type in IOCTL arguments in IOCTLs that were defined until
the use of enum was considered less than ideal. Recently Rémi Denis-Courmont
brought up the issue by proposing a patch to convert the enums to unsigned:

<URL:http://www.spinics.net/lists/linux-media/msg46167.html>

This sparked a long discussion where another solution to the issue was
proposed: two sets of IOCTL structures, one with __u32 and the other with
enums, and conversion code between the two:

<URL:http://www.spinics.net/lists/linux-media/msg47168.html>

Both approaches implement a complete solution that resolves the problem. The
first one is simple but requires assuming enums and __u32 are the same in
size (so we won't break the ABI) while the second one is more complex and
less clean but does not require making that assumption.

The issue boils down to whether enums are fundamentally different from __u32
or not, and can the former be substituted by the latter. During the
discussion it was concluded that the __u32 has the same size as enums on all
archs Linux is supported: it has not been shown that replacing those enums
in IOCTL arguments would break neither source or binary compatibility. If no
such reason is found, just replacing the enums with __u32s is the way to go.

This is what this patch does. This patch is slightly different from Remi's
first RFC (link above): it uses __u32 instead of unsigned and also changes
the arguments of VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY.
Signed-off-by: NRémi Denis-Courmont <remi@remlab.net>
Signed-off-by: NSakari Ailus <sakari.ailus@iki.fi>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      6016af82
  3. 02 5月, 2012 1 次提交
  5. 11 4月, 2012 5 次提交
  7. 20 3月, 2012 1 次提交
  9. 19 3月, 2012 1 次提交
  11. 08 3月, 2012 1 次提交
  13. 07 3月, 2012 1 次提交
  15. 29 2月, 2012 1 次提交
  17. 14 2月, 2012 2 次提交
  19. 24 1月, 2012 1 次提交
    • H
      [media] V4L2: Add per-device-node capabilities · 583aa3a9
      由 Hans Verkuil 提交于 
      If V4L2_CAP_DEVICE_CAPS is set, then the new device_caps field is filled with
the capabilities of the opened device node.

The capabilities field traditionally contains the capabilities of the physical
device, being a superset of all capabilities available at the several device
nodes. E.g., if you open /dev/video0, then if it contains VBI caps then that means
that there is a corresponding vbi node as well. And the capabilities field of
both the video and vbi nodes should contain identical caps.

However, it would be very useful to also have a capabilities field that contains
just the caps for the currently open device, hence the new CAP bit and field.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      583aa3a9
  21. 16 1月, 2012 4 次提交
  23. 11 1月, 2012 2 次提交
  25. 06 1月, 2012 1 次提交
  27. 31 12月, 2011 1 次提交
  29. 20 12月, 2011 2 次提交
  31. 11 12月, 2011 1 次提交
  33. 26 11月, 2011 3 次提交
  35. 04 11月, 2011 2 次提交
  37. 27 9月, 2011 1 次提交
  39. 21 9月, 2011 1 次提交
  41. 11 9月, 2011 1 次提交
  43. 29 8月, 2011 1 次提交
  45. 06 8月, 2011 1 次提交
  47. 28 7月, 2011 4 次提交