drm: Disable vblank interrupt immediately when drm_vblank_offdelay<0

Make drm_vblank_put() disable the vblank interrupt immediately when the
refcount drops to zero and drm_vblank_offdelay<0.

v2: Preserve the current drm_vblank_offdelay==0 'never disable' behaviur

Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Ville Syrjälä 2014-08-06 14:49:53 +03:00 committed by Daniel Vetter
parent ffe7c73a8d
commit 4ed0ce3d0b
4 changed files with 11 additions and 7 deletions

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@ -3386,6 +3386,7 @@ void (*disable_vblank) (struct drm_device *dev, int crtc);</synopsis>
by scheduling a timer. The delay is accessible through the vblankoffdelay
module parameter or the <varname>drm_vblank_offdelay</varname> global
variable and expressed in milliseconds. Its default value is 5000 ms.
Zero means never disable, and a negative value means disable immediately.
</para>
<para>
When a vertical blanking interrupt occurs drivers only need to call the

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@ -39,7 +39,7 @@
unsigned int drm_debug = 0; /* 1 to enable debug output */
EXPORT_SYMBOL(drm_debug);
unsigned int drm_vblank_offdelay = 5000; /* Default to 5000 msecs. */
int drm_vblank_offdelay = 5000; /* Default to 5000 msecs. */
unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */
@ -53,7 +53,7 @@ MODULE_AUTHOR(CORE_AUTHOR);
MODULE_DESCRIPTION(CORE_DESC);
MODULE_LICENSE("GPL and additional rights");
MODULE_PARM_DESC(debug, "Enable debug output");
MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs]");
MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)");
MODULE_PARM_DESC(timestamp_precision_usec, "Max. error on timestamps [usecs]");
MODULE_PARM_DESC(timestamp_monotonic, "Use monotonic timestamps");

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@ -993,10 +993,13 @@ void drm_vblank_put(struct drm_device *dev, int crtc)
BUG_ON(atomic_read(&vblank->refcount) == 0);
/* Last user schedules interrupt disable */
if (atomic_dec_and_test(&vblank->refcount) &&
(drm_vblank_offdelay > 0))
if (atomic_dec_and_test(&vblank->refcount)) {
if (drm_vblank_offdelay < 0)
vblank_disable_fn((unsigned long)vblank);
else if (drm_vblank_offdelay > 0)
mod_timer(&vblank->disable_timer,
jiffies + ((drm_vblank_offdelay * HZ)/1000));
}
}
EXPORT_SYMBOL(drm_vblank_put);

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@ -1345,7 +1345,7 @@ extern void drm_put_dev(struct drm_device *dev);
extern void drm_unplug_dev(struct drm_device *dev);
extern unsigned int drm_debug;
extern unsigned int drm_vblank_offdelay;
extern int drm_vblank_offdelay;
extern unsigned int drm_timestamp_precision;
extern unsigned int drm_timestamp_monotonic;