drm/i915: add comments on what stage a given PM handler is called
This will hopefully make it easier to navigate the code without the need
to consult the full PM documentation.
v2:
- add a comment that the freeze handler is also called after rebooting
- add a comment that the thaw handler is also called to recover from
errors (Ville)
- add the PM event names (PMSG_THAW etc.) for reference (Ville)
- add comments that s0ix can be handled both via system and runtime
suspend (Ville)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index bce58d3..035ec94 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1534,10 +1534,30 @@
}
static const struct dev_pm_ops i915_pm_ops = {
+ /*
+ * S0ix (via system suspend) and S3 event handlers [PMSG_SUSPEND,
+ * PMSG_RESUME]
+ */
.suspend = i915_pm_suspend,
.suspend_late = i915_pm_suspend_late,
.resume_early = i915_pm_resume_early,
.resume = i915_pm_resume,
+
+ /*
+ * S4 event handlers
+ * @freeze, @freeze_late : called (1) before creating the
+ * hibernation image [PMSG_FREEZE] and
+ * (2) after rebooting, before restoring
+ * the image [PMSG_QUIESCE]
+ * @thaw, @thaw_early : called (1) after creating the hibernation
+ * image, before writing it [PMSG_THAW]
+ * and (2) after failing to create or
+ * restore the image [PMSG_RECOVER]
+ * @poweroff, @poweroff_late: called after writing the hibernation
+ * image, before rebooting [PMSG_HIBERNATE]
+ * @restore, @restore_early : called after rebooting and restoring the
+ * hibernation image [PMSG_RESTORE]
+ */
.freeze = i915_pm_suspend,
.freeze_late = i915_pm_suspend_late,
.thaw_early = i915_pm_resume_early,
@@ -1546,6 +1566,8 @@
.poweroff_late = i915_pm_suspend_late,
.restore_early = i915_pm_resume_early,
.restore = i915_pm_resume,
+
+ /* S0ix (via runtime suspend) event handlers */
.runtime_suspend = intel_runtime_suspend,
.runtime_resume = intel_runtime_resume,
};