[media] v4l: v4l2_subdev userspace frame interval API
authorLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Wed, 5 May 2010 14:38:35 +0000 (11:38 -0300)
committerMauro Carvalho Chehab <mchehab@redhat.com>
Tue, 22 Mar 2011 07:53:32 +0000 (04:53 -0300)
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>
Documentation/DocBook/media-entities.tmpl
Documentation/DocBook/v4l/v4l2.xml
Documentation/DocBook/v4l/vidioc-subdev-enum-frame-interval.xml [new file with mode: 0644]
Documentation/DocBook/v4l/vidioc-subdev-g-frame-interval.xml [new file with mode: 0644]
drivers/media/video/v4l2-subdev.c
include/linux/v4l2-subdev.h
include/media/v4l2-subdev.h

index dbb9cb2e1ec60e7cafcc67772ee6fad6c83c75dc..a95eb5783760b320dcc53250ee2a6bebcd7f8224 100644 (file)
@@ -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>">
 <!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>">
 <!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">
index 2ada2f86bb54da5a141b1cde2b4c817b76bef74f..a436716ef3bcf45181149132ae10d401a72d3922 100644 (file)
@@ -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;
diff --git a/Documentation/DocBook/v4l/vidioc-subdev-enum-frame-interval.xml b/Documentation/DocBook/v4l/vidioc-subdev-enum-frame-interval.xml
new file mode 100644 (file)
index 0000000..2f8f4f0
--- /dev/null
@@ -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>
diff --git a/Documentation/DocBook/v4l/vidioc-subdev-g-frame-interval.xml b/Documentation/DocBook/v4l/vidioc-subdev-g-frame-interval.xml
new file mode 100644 (file)
index 0000000..0bc3ea2
--- /dev/null
@@ -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>
index 207cc5cceb299aee00b555a77f95738fefe1b57b..a4a12563ec3c71e6ac32542dab288ef9c5ef41fd 100644 (file)
@@ -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;
index 8dbb44873821c4f513ff3fca2891617a7eb47e3e..c55f9e9e1dd361a28f0ab75ea870d7d0cea12e5e 100644 (file)
@@ -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
index 4215650151be61c3d78dac369f7ecf316c3a19a0..8b7a78a013c696e6965bceaaa72561e7c3696bfb 100644 (file)
@@ -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,