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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-07 17:49:05 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-07 17:49:05 +0900
commit0b8e74c6f44094189dbe78baf4101acc7570c6af (patch)
tree6440561d09fb71ba5928664604ec92f29940be6b /Documentation/DocBook/media/v4l/common.xml
parent7f60ba388f5b9dd8b0da463b394412dace3ab814 (diff)
parentbd0d10498826ed150da5e4c45baf8b9c7088fb71 (diff)
downloadlwn-0b8e74c6f44094189dbe78baf4101acc7570c6af.tar.gz
lwn-0b8e74c6f44094189dbe78baf4101acc7570c6af.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: "The first part of the media updates for Kernel 3.7. This series contain: - A major tree renaming patch series: now, drivers are organized internally by their used bus, instead of by V4L2 and/or DVB API, providing a cleaner driver location for hybrid drivers that implement both APIs, and allowing to cleanup the Kconfig items and make them more intuitive for the end user; - Media Kernel developers are typically very lazy with their duties of keeping the MAINTAINERS entries for their drivers updated. As now the tree is more organized, we're doing an effort to add/update those entries for the drivers that aren't currently orphan; - Several DVB USB drivers got moved to a new DVB USB v2 core; the new core fixes several bugs (as the existing one that got bitroted). Now, suspend/resume finally started to work fine (at least with some devices - we should expect more work with regards to it); - added multistream support for DVB-T2, and unified the API for DVB-S2 and ISDB-S. Backward binary support is preserved; - as usual, a few new drivers, some V4L2 core improvements and lots of drivers improvements and fixes. There are some points to notice on this series: 1) you should expect a trivial merge conflict on your tree, with the removal of Documentation/feature-removal-schedule.txt: this series would be adding two additional entries there. I opted to not rebase it due to this recent change; 2) With regards to the PCTV 520e udev-related breakage, I opted to fix it in a way that the patches can be backported to 3.5 even without your firmware fix patch. This way, Greg doesn't need to rush backporting your patch (as there are still the firmware cache and firmware path customization issues to be addressed there). I'll send later a patch (likely after the end of the merge window) reverting the rest of the DRX-K async firmware request, fully restoring its original behaviour to allow media drivers to initialize everything serialized as before for 3.7 and upper. 3) I'm planning to work on this weekend to test the DMABUF patches for V4L2. The patches are on my queue for several Kernel cycles, but, up to now, there is/was no way to test the series locally. I have some concerns about this particular changeset with regards to security issues, and with regards to the replacement of the old VIDIOC_OVERLAY ioctl's that is broken on modern systems, due to GPU drivers change. The Overlay API allows direct PCI2PCI transfers from a media capture card into the GPU framebuffer, but its API is crappy. Also, the only existing X11 driver that implements it requires a XV extension that is not available anymore on modern drivers. The DMABUF can do the same thing, but with it is promising to be a properly-designed API. If I can successfully test this series and be happy with it, I should be asking you to pull them next week." * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (717 commits) em28xx: regression fix: use DRX-K sync firmware requests on em28xx drxk: allow loading firmware synchrousnously em28xx: Make all em28xx extensions to be initialized asynchronously [media] tda18271: properly report read errors in tda18271_get_id [media] tda18271: delay IR & RF calibration until init() if delay_cal is set [media] MAINTAINERS: add Michael Krufky as tda827x maintainer [media] MAINTAINERS: add Michael Krufky as tda8290 maintainer [media] MAINTAINERS: add Michael Krufky as cxusb maintainer [media] MAINTAINERS: add Michael Krufky as lg2160 maintainer [media] MAINTAINERS: add Michael Krufky as lgdt3305 maintainer [media] MAINTAINERS: add Michael Krufky as mxl111sf maintainer [media] MAINTAINERS: add Michael Krufky as mxl5007t maintainer [media] MAINTAINERS: add Michael Krufky as tda18271 maintainer [media] s5p-tv: Report only multi-plane capabilities in vidioc_querycap [media] s5p-mfc: Fix misplaced return statement in s5p_mfc_suspend() [media] exynos-gsc: Add missing static storage class specifiers [media] exynos-gsc: Remove <linux/version.h> header file inclusion [media] s5p-fimc: Fix incorrect condition in fimc_lite_reqbufs() [media] s5p-tv: Fix potential NULL pointer dereference error [media] s5k6aa: Fix possible NULL pointer dereference ...
Diffstat (limited to 'Documentation/DocBook/media/v4l/common.xml')
-rw-r--r--Documentation/DocBook/media/v4l/common.xml30
1 files changed, 14 insertions, 16 deletions
diff --git a/Documentation/DocBook/media/v4l/common.xml b/Documentation/DocBook/media/v4l/common.xml
index b91d25313b63..73c6847436c9 100644
--- a/Documentation/DocBook/media/v4l/common.xml
+++ b/Documentation/DocBook/media/v4l/common.xml
@@ -564,7 +564,7 @@ automatically.</para>
<para>To query and select the standard used by the current video
input or output applications call the &VIDIOC-G-STD; and
&VIDIOC-S-STD; ioctl, respectively. The <emphasis>received</emphasis>
-standard can be sensed with the &VIDIOC-QUERYSTD; ioctl. Note parameter of all these ioctls is a pointer to a &v4l2-std-id; type (a standard set), <emphasis>not</emphasis> an index into the standard enumeration.<footnote>
+standard can be sensed with the &VIDIOC-QUERYSTD; ioctl. Note that the parameter of all these ioctls is a pointer to a &v4l2-std-id; type (a standard set), <emphasis>not</emphasis> an index into the standard enumeration.<footnote>
<para>An alternative to the current scheme is to use pointers
to indices as arguments of <constant>VIDIOC_G_STD</constant> and
<constant>VIDIOC_S_STD</constant>, the &v4l2-input; and
@@ -588,30 +588,28 @@ switch to a standard by &v4l2-std-id;.</para>
</footnote> Drivers must implement all video standard ioctls
when the device has one or more video inputs or outputs.</para>
- <para>Special rules apply to USB cameras where the notion of video
-standards makes little sense. More generally any capture device,
-output devices accordingly, which is <itemizedlist>
+ <para>Special rules apply to devices such as USB cameras where the notion of video
+standards makes little sense. More generally for any capture or output device
+which is: <itemizedlist>
<listitem>
<para>incapable of capturing fields or frames at the nominal
rate of the video standard, or</para>
</listitem>
<listitem>
- <para>where <link linkend="buffer">timestamps</link> refer
-to the instant the field or frame was received by the driver, not the
-capture time, or</para>
- </listitem>
- <listitem>
- <para>where <link linkend="buffer">sequence numbers</link>
-refer to the frames received by the driver, not the captured
-frames.</para>
+ <para>that does not support the video standard formats at all.</para>
</listitem>
</itemizedlist> Here the driver shall set the
<structfield>std</structfield> field of &v4l2-input; and &v4l2-output;
-to zero, the <constant>VIDIOC_G_STD</constant>,
+to zero and the <constant>VIDIOC_G_STD</constant>,
<constant>VIDIOC_S_STD</constant>,
<constant>VIDIOC_QUERYSTD</constant> and
<constant>VIDIOC_ENUMSTD</constant> ioctls shall return the
-&EINVAL;.<footnote>
+&ENOTTY;.<footnote>
+ <para>See <xref linkend="buffer" /> for a rationale.</para>
+ <para>Applications can make use of the <xref linkend="input-capabilities" /> and
+<xref linkend="output-capabilities"/> flags to determine whether the video standard ioctls
+are available for the device.</para>
+&ENOTTY;.
<para>See <xref linkend="buffer" /> for a rationale. Probably
even USB cameras follow some well known video standard. It might have
been better to explicitly indicate elsewhere if a device cannot live
@@ -626,9 +624,9 @@ up to normal expectations, instead of this exception.</para>
&v4l2-standard; standard;
if (-1 == ioctl (fd, &VIDIOC-G-STD;, &amp;std_id)) {
- /* Note when VIDIOC_ENUMSTD always returns EINVAL this
+ /* Note when VIDIOC_ENUMSTD always returns ENOTTY this
is no video device or it falls under the USB exception,
- and VIDIOC_G_STD returning EINVAL is no error. */
+ and VIDIOC_G_STD returning ENOTTY is no error. */
perror ("VIDIOC_G_STD");
exit (EXIT_FAILURE);