From d673c02c4bdbcbe3076a2680f9c954be26b525c8 Mon Sep 17 00:00:00 2001
From: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Tue, 9 May 2017 16:03:25 +0200
Subject: drm/vblank: Switch drm_driver->get_vblank_timestamp to return a bool
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There's really no reason for anything more:
- Calling this while the crtc vblank stuff isn't set up is a driver
  bug. Those places alrready DRM_ERROR.
- Calling this when the crtc is off is either a driver bug (calling
  drm_crtc_handle_vblank at the wrong time) or a core bug (for
  anything else). Again, we DRM_ERROR.
- EINVAL is checked at higher levels already, and if we'd use struct
  drm_crtc * instead of (dev, pipe) it would be real obvious that
  those are again core bugs.

The only valid failure mode is crap hardware that couldn't sample a
useful timestamp, to ask the core to just grab a not-so-accurate
timestamp. Bool is perfectly fine for that.

v2: Also fix up the one caller, I lost that in the shuffling (Jani).

v3: Fixup commit message (Neil).

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Cc: Eric Anholt <eric@anholt.net>
Cc: Rob Clark <robdclark@gmail.com>
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170509140329.24114-1-daniel.vetter@ffwll.ch
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

(limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu.h')

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 6a81299..7b4f808 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -1910,10 +1910,10 @@ int amdgpu_device_resume(struct drm_device *dev, bool resume, bool fbcon);
 u32 amdgpu_get_vblank_counter_kms(struct drm_device *dev, unsigned int pipe);
 int amdgpu_enable_vblank_kms(struct drm_device *dev, unsigned int pipe);
 void amdgpu_disable_vblank_kms(struct drm_device *dev, unsigned int pipe);
-int amdgpu_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
-				    int *max_error,
-				    struct timeval *vblank_time,
-				    unsigned flags);
+bool amdgpu_get_vblank_timestamp_kms(struct drm_device *dev, unsigned int pipe,
+				     int *max_error,
+				     struct timeval *vblank_time,
+				     unsigned flags);
 long amdgpu_kms_compat_ioctl(struct file *filp, unsigned int cmd,
 			     unsigned long arg);
 
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