| Message ID | 5c449812e54fff0816282e712ab9e24c8b278cb6.1347023744.git.hans.verkuil@cisco.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 09/07/2012 03:29 PM, Hans Verkuil wrote: > From: Hans Verkuil<hans.verkuil@cisco.com> > > - S/TRY_FMT should always succeed, unless an invalid type field is passed in. > - TRY_FMT should give the same result as S_FMT, all other things being equal. > - ENUMFMT may return different formats for different inputs or outputs. > > This was decided during the 2012 Media Workshop. > > Signed-off-by: Hans Verkuil<hans.verkuil@cisco.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> A typo managed to snick in below... > --- > Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml | 3 +++ > Documentation/DocBook/media/v4l/vidioc-g-fmt.xml | 9 ++++++--- > 2 files changed, 9 insertions(+), 3 deletions(-) > > diff --git a/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml b/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml > index 81ebe48..0bd3324 100644 > --- a/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml > +++ b/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml > @@ -58,6 +58,9 @@ structure. Drivers fill the rest of the structure or return an > incrementing by one until<errorcode>EINVAL</errorcode> is > returned.</para> > > +<para>Note that after switching input or output the list of enumerated image > +formats may be different.</para> > + > <table pgwide="1" frame="none" id="v4l2-fmtdesc"> > <title>struct<structname>v4l2_fmtdesc</structname></title> > <tgroup cols="3"> > diff --git a/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml b/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml > index 52acff1..9ef279a 100644 > --- a/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml > +++ b/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml > @@ -81,7 +81,7 @@ the application calls the<constant>VIDIOC_S_FMT</constant> ioctl > with a pointer to a<structname>v4l2_format</structname> structure > the driver checks > and adjusts the parameters against hardware abilities. Drivers > -should not return an error code unless the input is ambiguous, this is > +should not return an error code unless the<structfield>type</structfield> field is invalid, this is > a mechanism to fathom device capabilities and to approach parameters > acceptable for both the application and driver. On success the driver > may program the hardware, allocate resources and generally prepare for > @@ -107,6 +107,10 @@ disabling I/O or possibly time consuming hardware preparations. > Although strongly recommended drivers are not required to implement > this ioctl.</para> > > +<para>The format as returned by<constant>VIDIOC_TRY_FMT</constant> > +must be identical to what<constant>VIDIOC_S_FMT</constant> returns for > +the same input or output.</para> > + > <table pgwide="1" frame="none" id="v4l2-format"> > <title>struct<structname>v4l2_format</structname></title> > <tgroup cols="4"> > @@ -187,8 +191,7 @@ capture and output devices.</entry> > <term><errorcode>EINVAL</errorcode></term> > <listitem> > <para>The&v4l2-format;<structfield>type</structfield> > -field is invalid, the requested buffer type not supported, or the > -format is not supported with this buffer type.</para> > +field is invalia or the requested buffer type not supported.</para> invalia -> invalid > </listitem> > </varlistentry> > </variablelist> -- Regards, Sylwester -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Friday 07 September 2012 15:29:04 Hans Verkuil wrote: > From: Hans Verkuil <hans.verkuil@cisco.com> > > - S/TRY_FMT should always succeed, unless an invalid type field is passed > in. - TRY_FMT should give the same result as S_FMT, all other things being > equal. - ENUMFMT may return different formats for different inputs or > outputs. > > This was decided during the 2012 Media Workshop. > > Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> With the typo fix reported by Sylwester, Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
diff --git a/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml b/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml index 81ebe48..0bd3324 100644 --- a/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml +++ b/Documentation/DocBook/media/v4l/vidioc-enum-fmt.xml @@ -58,6 +58,9 @@ structure. Drivers fill the rest of the structure or return an incrementing by one until <errorcode>EINVAL</errorcode> is returned.</para> + <para>Note that after switching input or output the list of enumerated image +formats may be different.</para> + <table pgwide="1" frame="none" id="v4l2-fmtdesc"> <title>struct <structname>v4l2_fmtdesc</structname></title> <tgroup cols="3"> diff --git a/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml b/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml index 52acff1..9ef279a 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-fmt.xml @@ -81,7 +81,7 @@ the application calls the <constant>VIDIOC_S_FMT</constant> ioctl with a pointer to a <structname>v4l2_format</structname> structure the driver checks and adjusts the parameters against hardware abilities. Drivers -should not return an error code unless the input is ambiguous, this is +should not return an error code unless the <structfield>type</structfield> field is invalid, this is a mechanism to fathom device capabilities and to approach parameters acceptable for both the application and driver. On success the driver may program the hardware, allocate resources and generally prepare for @@ -107,6 +107,10 @@ disabling I/O or possibly time consuming hardware preparations. Although strongly recommended drivers are not required to implement this ioctl.</para> + <para>The format as returned by <constant>VIDIOC_TRY_FMT</constant> +must be identical to what <constant>VIDIOC_S_FMT</constant> returns for +the same input or output.</para> + <table pgwide="1" frame="none" id="v4l2-format"> <title>struct <structname>v4l2_format</structname></title> <tgroup cols="4"> @@ -187,8 +191,7 @@ capture and output devices.</entry> <term><errorcode>EINVAL</errorcode></term> <listitem> <para>The &v4l2-format; <structfield>type</structfield> -field is invalid, the requested buffer type not supported, or the -format is not supported with this buffer type.</para> +field is invalia or the requested buffer type not supported.</para> </listitem> </varlistentry> </variablelist>