[media] v4l: v4l2_subdev userspace frame interval API

The three new ioctl VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL,
VIDIOC_SUBDEV_G_FRAME_INTERVAL and VIDIOC_SUBDEV_S_FRAME_INTERVAL can be
used to enumerate and configure a subdev's frame rate from userspace.

Two new video::g/s_frame_interval subdev operations are introduced to
support those ioctls. The existing video::g/s_parm operations are
deprecated and shouldn't be used anymore.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Laurent Pinchart 2010-05-05 11:38:35 -03:00 committed by Mauro Carvalho Chehab
parent 333c8b9778
commit 35c3017a29
7 changed files with 360 additions and 0 deletions

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@ -89,7 +89,9 @@
<!ENTITY VIDIOC-SUBDEV-ENUM-FRAME-SIZE "<link linkend='vidioc-subdev-enum-frame-size'><constant>VIDIOC_SUBDEV_ENUM_FRAME_SIZE</constant></link>">
<!ENTITY VIDIOC-SUBDEV-ENUM-MBUS-CODE "<link linkend='vidioc-subdev-enum-mbus-code'><constant>VIDIOC_SUBDEV_ENUM_MBUS_CODE</constant></link>">
<!ENTITY VIDIOC-SUBDEV-G-FMT "<link linkend='vidioc-subdev-g-fmt'><constant>VIDIOC_SUBDEV_G_FMT</constant></link>">
<!ENTITY VIDIOC-SUBDEV-G-FRAME-INTERVAL "<link linkend='vidioc-subdev-g-frame-interval'><constant>VIDIOC_SUBDEV_G_FRAME_INTERVAL</constant></link>">
<!ENTITY VIDIOC-SUBDEV-S-FMT "<link linkend='vidioc-subdev-g-fmt'><constant>VIDIOC_SUBDEV_S_FMT</constant></link>">
<!ENTITY VIDIOC-SUBDEV-S-FRAME-INTERVAL "<link linkend='vidioc-subdev-g-frame-interval'><constant>VIDIOC_SUBDEV_S_FRAME_INTERVAL</constant></link>">
<!ENTITY VIDIOC-TRY-ENCODER-CMD "<link linkend='vidioc-encoder-cmd'><constant>VIDIOC_TRY_ENCODER_CMD</constant></link>">
<!ENTITY VIDIOC-TRY-EXT-CTRLS "<link linkend='vidioc-g-ext-ctrls'><constant>VIDIOC_TRY_EXT_CTRLS</constant></link>">
<!ENTITY VIDIOC-TRY-FMT "<link linkend='vidioc-g-fmt'><constant>VIDIOC_TRY_FMT</constant></link>">
@ -193,6 +195,8 @@
<!ENTITY v4l2-sliced-vbi-cap "struct&nbsp;<link linkend='v4l2-sliced-vbi-cap'>v4l2_sliced_vbi_cap</link>">
<!ENTITY v4l2-sliced-vbi-data "struct&nbsp;<link linkend='v4l2-sliced-vbi-data'>v4l2_sliced_vbi_data</link>">
<!ENTITY v4l2-sliced-vbi-format "struct&nbsp;<link linkend='v4l2-sliced-vbi-format'>v4l2_sliced_vbi_format</link>">
<!ENTITY v4l2-subdev-frame-interval "struct&nbsp;<link linkend='v4l2-subdev-frame-interval'>v4l2_subdev_frame_interval</link>">
<!ENTITY v4l2-subdev-frame-interval-enum "struct&nbsp;<link linkend='v4l2-subdev-frame-interval-enum'>v4l2_subdev_frame_interval_enum</link>">
<!ENTITY v4l2-subdev-frame-size-enum "struct&nbsp;<link linkend='v4l2-subdev-frame-size-enum'>v4l2_subdev_frame_size_enum</link>">
<!ENTITY v4l2-subdev-format "struct&nbsp;<link linkend='v4l2-subdev-format'>v4l2_subdev_format</link>">
<!ENTITY v4l2-subdev-mbus-code-enum "struct&nbsp;<link linkend='v4l2-subdev-mbus-code-enum'>v4l2_subdev_mbus_code_enum</link>">
@ -331,10 +335,12 @@
<!ENTITY sub-reqbufs SYSTEM "v4l/vidioc-reqbufs.xml">
<!ENTITY sub-s-hw-freq-seek SYSTEM "v4l/vidioc-s-hw-freq-seek.xml">
<!ENTITY sub-streamon SYSTEM "v4l/vidioc-streamon.xml">
<!ENTITY sub-subdev-enum-frame-interval SYSTEM "v4l/vidioc-subdev-enum-frame-interval.xml">
<!ENTITY sub-subdev-enum-frame-size SYSTEM "v4l/vidioc-subdev-enum-frame-size.xml">
<!ENTITY sub-subdev-enum-mbus-code SYSTEM "v4l/vidioc-subdev-enum-mbus-code.xml">
<!ENTITY sub-subdev-formats SYSTEM "v4l/subdev-formats.xml">
<!ENTITY sub-subdev-g-fmt SYSTEM "v4l/vidioc-subdev-g-fmt.xml">
<!ENTITY sub-subdev-g-frame-interval SYSTEM "v4l/vidioc-subdev-g-frame-interval.xml">
<!ENTITY sub-capture-c SYSTEM "v4l/capture.c.xml">
<!ENTITY sub-keytable-c SYSTEM "v4l/keytable.c.xml">
<!ENTITY sub-v4l2grab-c SYSTEM "v4l/v4l2grab.c.xml">

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@ -507,9 +507,11 @@ and discussions on the V4L mailing list.</revremark>
&sub-reqbufs;
&sub-s-hw-freq-seek;
&sub-streamon;
&sub-subdev-enum-frame-interval;
&sub-subdev-enum-frame-size;
&sub-subdev-enum-mbus-code;
&sub-subdev-g-fmt;
&sub-subdev-g-frame-interval;
&sub-subscribe-event;
<!-- End of ioctls. -->
&sub-mmap;

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@ -0,0 +1,152 @@
<refentry id="vidioc-subdev-enum-frame-interval">
<refmeta>
<refentrytitle>ioctl VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL</refentrytitle>
&manvol;
</refmeta>
<refnamediv>
<refname>VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL</refname>
<refpurpose>Enumerate frame intervals</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcprototype>
<funcdef>int <function>ioctl</function></funcdef>
<paramdef>int <parameter>fd</parameter></paramdef>
<paramdef>int <parameter>request</parameter></paramdef>
<paramdef>struct v4l2_subdev_frame_interval_enum *
<parameter>argp</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>fd</parameter></term>
<listitem>
<para>&fd;</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>request</parameter></term>
<listitem>
<para>VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>argp</parameter></term>
<listitem>
<para></para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<note>
<title>Experimental</title>
<para>This is an <link linkend="experimental">experimental</link>
interface and may change in the future.</para>
</note>
<para>This ioctl lets applications enumerate available frame intervals on a
given sub-device pad. Frame intervals only makes sense for sub-devices that
can control the frame period on their own. This includes, for instance,
image sensors and TV tuners.</para>
<para>For the common use case of image sensors, the frame intervals
available on the sub-device output pad depend on the frame format and size
on the same pad. Applications must thus specify the desired format and size
when enumerating frame intervals.</para>
<para>To enumerate frame intervals applications initialize the
<structfield>index</structfield>, <structfield>pad</structfield>,
<structfield>code</structfield>, <structfield>width</structfield> and
<structfield>height</structfield> fields of
&v4l2-subdev-frame-interval-enum; and call the
<constant>VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL</constant> ioctl with a pointer
to this structure. Drivers fill the rest of the structure or return
an &EINVAL; if one of the input fields is invalid. All frame intervals are
enumerable by beginning at index zero and incrementing by one until
<errorcode>EINVAL</errorcode> is returned.</para>
<para>Available frame intervals may depend on the current 'try' formats
at other pads of the sub-device, as well as on the current active links. See
&VIDIOC-SUBDEV-G-FMT; for more information about the try formats.</para>
<para>Sub-devices that support the frame interval enumeration ioctl should
implemented it on a single pad only. Its behaviour when supported on
multiple pads of the same sub-device is not defined.</para>
<table pgwide="1" frame="none" id="v4l2-subdev-frame-interval-enum">
<title>struct <structname>v4l2_subdev_frame_interval_enum</structname></title>
<tgroup cols="3">
&cs-str;
<tbody valign="top">
<row>
<entry>__u32</entry>
<entry><structfield>index</structfield></entry>
<entry>Number of the format in the enumeration, set by the
application.</entry>
</row>
<row>
<entry>__u32</entry>
<entry><structfield>pad</structfield></entry>
<entry>Pad number as reported by the media controller API.</entry>
</row>
<row>
<entry>__u32</entry>
<entry><structfield>code</structfield></entry>
<entry>The media bus format code, as defined in
<xref linkend="v4l2-mbus-format" />.</entry>
</row>
<row>
<entry>__u32</entry>
<entry><structfield>width</structfield></entry>
<entry>Frame width, in pixels.</entry>
</row>
<row>
<entry>__u32</entry>
<entry><structfield>height</structfield></entry>
<entry>Frame height, in pixels.</entry>
</row>
<row>
<entry>&v4l2-fract;</entry>
<entry><structfield>interval</structfield></entry>
<entry>Period, in seconds, between consecutive video frames.</entry>
</row>
<row>
<entry>__u32</entry>
<entry><structfield>reserved</structfield>[9]</entry>
<entry>Reserved for future extensions. Applications and drivers must
set the array to zero.</entry>
</row>
</tbody>
</tgroup>
</table>
</refsect1>
<refsect1>
&return-value;
<variablelist>
<varlistentry>
<term><errorcode>EINVAL</errorcode></term>
<listitem>
<para>The &v4l2-subdev-frame-interval-enum;
<structfield>pad</structfield> references a non-existing pad, one of
the <structfield>code</structfield>, <structfield>width</structfield>
or <structfield>height</structfield> fields are invalid for the given
pad or the <structfield>index</structfield> field is out of bounds.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
</refentry>

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@ -0,0 +1,141 @@
<refentry id="vidioc-subdev-g-frame-interval">
<refmeta>
<refentrytitle>ioctl VIDIOC_SUBDEV_G_FRAME_INTERVAL, VIDIOC_SUBDEV_S_FRAME_INTERVAL</refentrytitle>
&manvol;
</refmeta>
<refnamediv>
<refname>VIDIOC_SUBDEV_G_FRAME_INTERVAL</refname>
<refname>VIDIOC_SUBDEV_S_FRAME_INTERVAL</refname>
<refpurpose>Get or set the frame interval on a subdev pad</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcprototype>
<funcdef>int <function>ioctl</function></funcdef>
<paramdef>int <parameter>fd</parameter></paramdef>
<paramdef>int <parameter>request</parameter></paramdef>
<paramdef>struct v4l2_subdev_frame_interval *<parameter>argp</parameter>
</paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>fd</parameter></term>
<listitem>
<para>&fd;</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>request</parameter></term>
<listitem>
<para>VIDIOC_SUBDEV_G_FRAME_INTERVAL, VIDIOC_SUBDEV_S_FRAME_INTERVAL</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>argp</parameter></term>
<listitem>
<para></para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<note>
<title>Experimental</title>
<para>This is an <link linkend="experimental">experimental</link>
interface and may change in the future.</para>
</note>
<para>These ioctls are used to get and set the frame interval at specific
subdev pads in the image pipeline. The frame interval only makes sense for
sub-devices that can control the frame period on their own. This includes,
for instance, image sensors and TV tuners. Sub-devices that don't support
frame intervals must not implement these ioctls.</para>
<para>To retrieve the current frame interval applications set the
<structfield>pad</structfield> field of a &v4l2-subdev-frame-interval; to
the desired pad number as reported by the media controller API. When they
call the <constant>VIDIOC_SUBDEV_G_FRAME_INTERVAL</constant> ioctl with a
pointer to this structure the driver fills the members of the
<structfield>interval</structfield> field.</para>
<para>To change the current frame interval applications set both the
<structfield>pad</structfield> field and all members of the
<structfield>interval</structfield> field. When they call the
<constant>VIDIOC_SUBDEV_S_FRAME_INTERVAL</constant> ioctl with a pointer to
this structure the driver verifies the requested interval, adjusts it based
on the hardware capabilities and configures the device. Upon return the
&v4l2-subdev-frame-interval; contains the current frame interval as would be
returned by a <constant>VIDIOC_SUBDEV_G_FRAME_INTERVAL</constant> call.
</para>
<para>Drivers must not return an error solely because the requested interval
doesn't match the device capabilities. They must instead modify the interval
to match what the hardware can provide. The modified interval should be as
close as possible to the original request.</para>
<para>Sub-devices that support the frame interval ioctls should implement
them on a single pad only. Their behaviour when supported on multiple pads
of the same sub-device is not defined.</para>
<table pgwide="1" frame="none" id="v4l2-subdev-frame-interval">
<title>struct <structname>v4l2_subdev_frame_interval</structname></title>
<tgroup cols="3">
&cs-str;
<tbody valign="top">
<row>
<entry>__u32</entry>
<entry><structfield>pad</structfield></entry>
<entry>Pad number as reported by the media controller API.</entry>
</row>
<row>
<entry>&v4l2-fract;</entry>
<entry><structfield>interval</structfield></entry>
<entry>Period, in seconds, between consecutive video frames.</entry>
</row>
<row>
<entry>__u32</entry>
<entry><structfield>reserved</structfield>[9]</entry>
<entry>Reserved for future extensions. Applications and drivers must
set the array to zero.</entry>
</row>
</tbody>
</tgroup>
</table>
</refsect1>
<refsect1>
&return-value;
<variablelist>
<varlistentry>
<term><errorcode>EBUSY</errorcode></term>
<listitem>
<para>The frame interval can't be changed because the pad is currently
busy. This can be caused, for instance, by an active video stream on
the pad. The ioctl must not be retried without performing another
action to fix the problem first. Only returned by
<constant>VIDIOC_SUBDEV_S_FRAME_INTERVAL</constant></para>
</listitem>
</varlistentry>
<varlistentry>
<term><errorcode>EINVAL</errorcode></term>
<listitem>
<para>The &v4l2-subdev-frame-interval; <structfield>pad</structfield>
references a non-existing pad, or the pad doesn't support frame
intervals.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
</refentry>

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@ -232,6 +232,22 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
return v4l2_subdev_call(sd, pad, enum_frame_size, subdev_fh,
fse);
}
case VIDIOC_SUBDEV_G_FRAME_INTERVAL:
return v4l2_subdev_call(sd, video, g_frame_interval, arg);
case VIDIOC_SUBDEV_S_FRAME_INTERVAL:
return v4l2_subdev_call(sd, video, s_frame_interval, arg);
case VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL: {
struct v4l2_subdev_frame_interval_enum *fie = arg;
if (fie->pad >= sd->entity.num_pads)
return -EINVAL;
return v4l2_subdev_call(sd, pad, enum_frame_interval, subdev_fh,
fie);
}
#endif
default:
return -ENOIOCTLCMD;

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@ -80,11 +80,47 @@ struct v4l2_subdev_frame_size_enum {
__u32 reserved[9];
};
/**
* struct v4l2_subdev_frame_interval - Pad-level frame rate
* @pad: pad number, as reported by the media API
* @interval: frame interval in seconds
*/
struct v4l2_subdev_frame_interval {
__u32 pad;
struct v4l2_fract interval;
__u32 reserved[9];
};
/**
* struct v4l2_subdev_frame_interval_enum - Frame interval enumeration
* @pad: pad number, as reported by the media API
* @index: frame interval index during enumeration
* @code: format code (from enum v4l2_mbus_pixelcode)
* @width: frame width in pixels
* @height: frame height in pixels
* @interval: frame interval in seconds
*/
struct v4l2_subdev_frame_interval_enum {
__u32 index;
__u32 pad;
__u32 code;
__u32 width;
__u32 height;
struct v4l2_fract interval;
__u32 reserved[9];
};
#define VIDIOC_SUBDEV_G_FMT _IOWR('V', 4, struct v4l2_subdev_format)
#define VIDIOC_SUBDEV_S_FMT _IOWR('V', 5, struct v4l2_subdev_format)
#define VIDIOC_SUBDEV_G_FRAME_INTERVAL \
_IOWR('V', 21, struct v4l2_subdev_frame_interval)
#define VIDIOC_SUBDEV_S_FRAME_INTERVAL \
_IOWR('V', 22, struct v4l2_subdev_frame_interval)
#define VIDIOC_SUBDEV_ENUM_MBUS_CODE \
_IOWR('V', 2, struct v4l2_subdev_mbus_code_enum)
#define VIDIOC_SUBDEV_ENUM_FRAME_SIZE \
_IOWR('V', 74, struct v4l2_subdev_frame_size_enum)
#define VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL \
_IOWR('V', 75, struct v4l2_subdev_frame_interval_enum)
#endif

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@ -268,6 +268,10 @@ struct v4l2_subdev_video_ops {
int (*s_crop)(struct v4l2_subdev *sd, struct v4l2_crop *crop);
int (*g_parm)(struct v4l2_subdev *sd, struct v4l2_streamparm *param);
int (*s_parm)(struct v4l2_subdev *sd, struct v4l2_streamparm *param);
int (*g_frame_interval)(struct v4l2_subdev *sd,
struct v4l2_subdev_frame_interval *interval);
int (*s_frame_interval)(struct v4l2_subdev *sd,
struct v4l2_subdev_frame_interval *interval);
int (*enum_framesizes)(struct v4l2_subdev *sd, struct v4l2_frmsizeenum *fsize);
int (*enum_frameintervals)(struct v4l2_subdev *sd, struct v4l2_frmivalenum *fival);
int (*enum_dv_presets) (struct v4l2_subdev *sd,
@ -420,6 +424,9 @@ struct v4l2_subdev_pad_ops {
int (*enum_frame_size)(struct v4l2_subdev *sd,
struct v4l2_subdev_fh *fh,
struct v4l2_subdev_frame_size_enum *fse);
int (*enum_frame_interval)(struct v4l2_subdev *sd,
struct v4l2_subdev_fh *fh,
struct v4l2_subdev_frame_interval_enum *fie);
int (*get_fmt)(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh,
struct v4l2_subdev_format *format);
int (*set_fmt)(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh,