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DocBook/drm: Use a <variablelist> for vblank ioctls

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Signed-off-by: Michael Witten <mfwitten@gmail.com>
This commit is contained in:
Michael Witten 2011-08-25 21:11:30 +00:00
parent 65ffef508f
commit 51b9500de2
1 changed files with 25 additions and 14 deletions
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39
Documentation/DocBook/drm.tmpl
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@ -619,22 +619,33 @@ void intel_crt_init(struct drm_device *dev)
<title>VBlank event handling</title>
<para>
The DRM core exposes two vertical blank related ioctls:
DRM_IOCTL_WAIT_VBLANK and DRM_IOCTL_MODESET_CTL.
<variablelist>
<varlistentry>
<term>DRM_IOCTL_WAIT_VBLANK</term>
<listitem>
<para>
This takes a struct drm_wait_vblank structure as its argument,
and it is used to block or request a signal when a specified
vblank event occurs.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>DRM_IOCTL_MODESET_CTL</term>
<listitem>
<para>
This should be called by application level drivers before and
after mode setting, since on many devices the vertical blank
counter is reset at that time. Internally, the DRM snapshots
the last vblank count when the ioctl is called with the
_DRM_PRE_MODESET command so that the counter won't go backwards
(which is dealt with when _DRM_POST_MODESET is used).
</para>
</listitem>
</varlistentry>
</variablelist>
<!--!Edrivers/char/drm/drm_irq.c-->
</para>
<para>
DRM_IOCTL_WAIT_VBLANK takes a struct drm_wait_vblank structure
as its argument, and is used to block or request a signal when a
specified vblank event occurs.
</para>
<para>
DRM_IOCTL_MODESET_CTL should be called by application level
drivers before and after mode setting, since on many devices, the
vertical blank counter is reset at that time. Internally,
the DRM snapshots the last vblank count when the ioctl is called
with the _DRM_PRE_MODESET command so that the counter won't go
backwards (which is dealt with when _DRM_POST_MODESET is used).
</para>
<para>
To support the functions above, the DRM core provides several
helper functions for tracking vertical blank counters, and