diff options
Diffstat (limited to 'Documentation/DocBook/media/v4l')
5 files changed, 37 insertions, 20 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml index 6f1f9a629dc..b17a7aac699 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml @@ -183,7 +183,12 @@ applications must set the array to zero.</entry> <entry>__u32</entry> <entry><structfield>ctrl_class</structfield></entry> <entry>The control class to which all controls belong, see -<xref linkend="ctrl-class" />.</entry> +<xref linkend="ctrl-class" />. Drivers that use a kernel framework for handling +controls will also accept a value of 0 here, meaning that the controls can +belong to any control class. Whether drivers support this can be tested by setting +<structfield>ctrl_class</structfield> to 0 and calling <constant>VIDIOC_TRY_EXT_CTRLS</constant> +with a <structfield>count</structfield> of 0. If that succeeds, then the driver +supports this feature.</entry> </row> <row> <entry>__u32</entry> @@ -194,10 +199,13 @@ also be zero.</entry> <row> <entry>__u32</entry> <entry><structfield>error_idx</structfield></entry> - <entry>Set by the driver in case of an error. It is the -index of the control causing the error or equal to 'count' when the -error is not associated with a particular control. Undefined when the -ioctl returns 0 (success).</entry> + <entry>Set by the driver in case of an error. If it is equal +to <structfield>count</structfield>, then no actual changes were made to +controls. In other words, the error was not associated with setting a particular +control. If it is another value, then only the controls up to <structfield>error_idx-1</structfield> +were modified and control <structfield>error_idx</structfield> is the one that +caused the error. The <structfield>error_idx</structfield> value is undefined +if the ioctl returned 0 (success).</entry> </row> <row> <entry>__u32</entry> diff --git a/Documentation/DocBook/media/v4l/vidioc-g-fbuf.xml b/Documentation/DocBook/media/v4l/vidioc-g-fbuf.xml index 93817f33703..7c63815e7af 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-fbuf.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-fbuf.xml @@ -364,15 +364,20 @@ capability and it is cleared otherwise.</entry> <row> <entry><constant>V4L2_FBUF_FLAG_OVERLAY</constant></entry> <entry>0x0002</entry> - <entry>The frame buffer is an overlay surface the same -size as the capture. [?]</entry> - </row> - <row> - <entry spanname="hspan">The purpose of -<constant>V4L2_FBUF_FLAG_OVERLAY</constant> was never quite clear. -Most drivers seem to ignore this flag. For compatibility with the -<wordasword>bttv</wordasword> driver applications should set the -<constant>V4L2_FBUF_FLAG_OVERLAY</constant> flag.</entry> + <entry>If this flag is set for a video capture device, then the +driver will set the initial overlay size to cover the full framebuffer size, +otherwise the existing overlay size (as set by &VIDIOC-S-FMT;) will be used. + +Only one video capture driver (bttv) supports this flag. The use of this flag +for capture devices is deprecated. There is no way to detect which drivers +support this flag, so the only reliable method of setting the overlay size is +through &VIDIOC-S-FMT;. + +If this flag is set for a video output device, then the video output overlay +window is relative to the top-left corner of the framebuffer and restricted +to the size of the framebuffer. If it is cleared, then the video output +overlay window is relative to the video output display. + </entry> </row> <row> <entry><constant>V4L2_FBUF_FLAG_CHROMAKEY</constant></entry> diff --git a/Documentation/DocBook/media/v4l/vidioc-g-frequency.xml b/Documentation/DocBook/media/v4l/vidioc-g-frequency.xml index 16431813beb..66e9a525786 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-frequency.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-frequency.xml @@ -98,8 +98,11 @@ the &v4l2-output; <structfield>modulator</structfield> field and the <entry>&v4l2-tuner-type;</entry> <entry><structfield>type</structfield></entry> <entry>The tuner type. This is the same value as in the -&v4l2-tuner; <structfield>type</structfield> field. The field is not -applicable to modulators, &ie; ignored by drivers.</entry> +&v4l2-tuner; <structfield>type</structfield> field. The type must be set +to <constant>V4L2_TUNER_RADIO</constant> for <filename>/dev/radioX</filename> +device nodes, and to <constant>V4L2_TUNER_ANALOG_TV</constant> +for all others. The field is not applicable to modulators, &ie; ignored +by drivers.</entry> </row> <row> <entry>__u32</entry> diff --git a/Documentation/DocBook/media/v4l/vidioc-g-input.xml b/Documentation/DocBook/media/v4l/vidioc-g-input.xml index 08ae82f131f..1d43065090d 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-input.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-input.xml @@ -61,8 +61,8 @@ desired input in an integer and call the <constant>VIDIOC_S_INPUT</constant> ioctl with a pointer to this integer. Side effects are possible. For example inputs may support different video standards, so the driver may implicitly switch the -current standard. It is good practice to select an input before -querying or negotiating any other parameters.</para> +current standard. Because of these possible side effects applications +must select an input before querying or negotiating any other parameters.</para> <para>Information about video inputs is available using the &VIDIOC-ENUMINPUT; ioctl.</para> diff --git a/Documentation/DocBook/media/v4l/vidioc-g-output.xml b/Documentation/DocBook/media/v4l/vidioc-g-output.xml index fd45f1c13cc..4533068ecb8 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-output.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-output.xml @@ -61,8 +61,9 @@ desired output in an integer and call the <constant>VIDIOC_S_OUTPUT</constant> ioctl with a pointer to this integer. Side effects are possible. For example outputs may support different video standards, so the driver may implicitly switch the current -standard. It is good practice to select an output before querying or -negotiating any other parameters.</para> +standard. +standard. Because of these possible side effects applications +must select an output before querying or negotiating any other parameters.</para> <para>Information about video outputs is available using the &VIDIOC-ENUMOUTPUT; ioctl.</para> |