summaryrefslogtreecommitdiffstats
path: root/Documentation/DocBook/media/v4l/vidioc-querycap.xml
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-23 22:39:09 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-23 22:39:09 +0100
commite317234975cb7463b8ca21a93bb6862d9dcf113f (patch)
tree4446fa3a21364f3cba23a22aa2a94027f169d8df /Documentation/DocBook/media/v4l/vidioc-querycap.xml
parentMerge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/g... (diff)
parentMerge branch 'staging/for_v3.4' into v4l_for_linus (diff)
downloadlinux-e317234975cb7463b8ca21a93bb6862d9dcf113f.tar.xz
linux-e317234975cb7463b8ca21a93bb6862d9dcf113f.zip
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab: - V4L2 API additions to better support JPEG compression control - media API additions to properly support MPEG decoders - V4L2 API additions for image crop/scaling - a few other V4L2 API DocBook fixes/improvements - two new DVB frontend drivers: m88rs2000 and rtl2830 - two new DVB drivers: az6007 and rtl28xxu - a framework for ISA drivers, that removed lots of common code found at the ISA radio drivers - a new FM transmitter driver (radio-keene) - a GPIO-based IR receiver driver - a new sensor driver: mt9m032 - some new video drivers: adv7183, blackfin, mx2_emmaprp, sii9234_drv, vs6624 - several new board additions, driver fixes, improvements and cleanups. * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (295 commits) [media] update CARDLIST.em28xx [media] partially reverts changeset fa5527c [media] stb0899: fix the limits for signal strength values [media] em28xx: support for 2304:0242 PCTV QuatroStick (510e) [media] em28xx: support for 2013:0251 PCTV QuatroStick nano (520e) [media] -EINVAL -> -ENOTTY [media] gspca - sn9c20x: Cleanup source [media] gspca - sn9c20x: Simplify register write for capture start/stop [media] gspca - sn9c20x: Add automatic JPEG compression mechanism [media] gspca - sn9c20x: Greater delay in case of sensor no response [media] gspca - sn9c20x: Optimize the code of write sequences [media] gspca - sn9c20x: Add the JPEG compression quality control [media] gspca - sn9c20x: Add a delay after Omnivision sensor reset [media] gspca - sn9c20x: Propagate USB errors to higher level [media] gspca - sn9c20x: Use the new video control mechanism [media] gspca - sn9c20x: Fix loss of frame start [media] gspca - zc3xx: Lack of register 08 value for sensor cs2102k [media] gspca - ov534_9: Add brightness to OmniVision 5621 sensor [media] gspca - zc3xx: Add V4L2_CID_JPEG_COMPRESSION_QUALITY control support [media] pvrusb2: fix 7MHz & 8MHz DVB-T tuner support for HVR1900 rev D1F5 ...
Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-querycap.xml')
-rw-r--r--Documentation/DocBook/media/v4l/vidioc-querycap.xml36
1 files changed, 33 insertions, 3 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-querycap.xml b/Documentation/DocBook/media/v4l/vidioc-querycap.xml
index e3664d6f2de4..4643505cd4ca 100644
--- a/Documentation/DocBook/media/v4l/vidioc-querycap.xml
+++ b/Documentation/DocBook/media/v4l/vidioc-querycap.xml
@@ -124,12 +124,35 @@ printf ("Version: %u.%u.%u\n",
<row>
<entry>__u32</entry>
<entry><structfield>capabilities</structfield></entry>
- <entry>Device capabilities, see <xref
- linkend="device-capabilities" />.</entry>
+ <entry>Available capabilities of the physical device as a whole, see <xref
+ linkend="device-capabilities" />. The same physical device can export
+ multiple devices in /dev (e.g. /dev/videoX, /dev/vbiY and /dev/radioZ).
+ The <structfield>capabilities</structfield> field should contain a union
+ of all capabilities available around the several V4L2 devices exported
+ to userspace.
+ For all those devices the <structfield>capabilities</structfield> field
+ returns the same set of capabilities. This allows applications to open
+ just one of the devices (typically the video device) and discover whether
+ video, vbi and/or radio are also supported.
+ </entry>
</row>
<row>
<entry>__u32</entry>
- <entry><structfield>reserved</structfield>[4]</entry>
+ <entry><structfield>device_caps</structfield></entry>
+ <entry>Device capabilities of the opened device, see <xref
+ linkend="device-capabilities" />. Should contain the available capabilities
+ of that specific device node. So, for example, <structfield>device_caps</structfield>
+ of a radio device will only contain radio related capabilities and
+ no video or vbi capabilities. This field is only set if the <structfield>capabilities</structfield>
+ field contains the <constant>V4L2_CAP_DEVICE_CAPS</constant> capability.
+ Only the <structfield>capabilities</structfield> field can have the
+ <constant>V4L2_CAP_DEVICE_CAPS</constant> capability, <structfield>device_caps</structfield>
+ will never set <constant>V4L2_CAP_DEVICE_CAPS</constant>.
+ </entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>reserved</structfield>[3]</entry>
<entry>Reserved for future extensions. Drivers must set
this array to zero.</entry>
</row>
@@ -276,6 +299,13 @@ linkend="async">asynchronous</link> I/O methods.</entry>
<entry>The device supports the <link
linkend="mmap">streaming</link> I/O method.</entry>
</row>
+ <row>
+ <entry><constant>V4L2_CAP_DEVICE_CAPS</constant></entry>
+ <entry>0x80000000</entry>
+ <entry>The driver fills the <structfield>device_caps</structfield>
+ field. This capability can only appear in the <structfield>capabilities</structfield>
+ field and never in the <structfield>device_caps</structfield> field.</entry>
+ </row>
</tbody>
</tgroup>
</table>