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2012-05-14[media] v4l2: use __u32 rather than enums in ioctl() structsSakari Ailus1-1/+1
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: Rémi Denis-Courmont <remi@remlab.net> Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-04-10[media] v4l: Document integer menu controlsSakari Ailus1-2/+37
Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-12-11[media] Remove unneeded comments from the media API DocBook filesSylwester Nawrocki1-8/+0
This removes comment tags intended for emacs configuration from 67 files in the Media API DocBook. Such comments are not really helpful and violate the coding style rules. Signed-off-by: Sylwester Nawrocki <snjw23@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-09-21[media] videodev2.h: add V4L2_CTRL_FLAG_VOLATILEHans Verkuil1-0/+9
Add a new VOLATILE control flag that is set for volatile controls. That way applications know whether the value of the control is volatile (i.e. can change continuously) or not. Until now this was an internal property, but it is useful to know in userspace as well. A typical use case is the gain value when autogain is on. In that case the hardware will continuously adjust the gain based various environmental factors. This patch just adds and documents the flag, it's not yet used. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-28[media] DocBook: document V4L2_CTRL_TYPE_BITMASKHans Verkuil1-1/+11
[mchehab@redhat.com: Fix a merge conflict and make compat.xml coherent with v4l2.xml] Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Sakari Ailus <sakari.ailus@iki.fi> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-28[media] DocBook: Move all media docbook stuff into its own directoryMauro Carvalho Chehab1-0/+434
This patch addresses several issues pointed by Randy Dunlap <rdunlap@xenotime.net> at changeset ece722c: - In the generated index.html file, "media" is listed first, but it should be listed in alphabetical order, not first. - The generated files are (hidden) in .tmpmedia/ - The link from the top-level index.html file to "media" is to media/index.html, but the file is actually in .tmpmedia/media/index.html - Please build docs with and without using "O=builddir" and test that. - Would it be possible for media to have its own Makefile instead of merging into this one? Due to the way cleandocs target works, I had to rename the media DocBook to media_api, otherwise cleandocs would remove the /media directory. Thanks-to: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>