renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2025-01-01 10:13:58 +08:00
Code

drm/i915/lvds: Ensure the HW is powered during HW state readout

Browse Source 
The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-13-git-send-email-imre.deak@intel.com
(cherry picked from commit ecb2448218)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This commit is contained in:
Imre Deak 2016-02-12 18:55:21 +02:00 committed by Jani Nikula
parent 31feb61a68
commit 380bdff2d0
1 changed files with 11 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/gpu/drm/i915/intel_lvds.c
View File

@ -75,22 +75,30 @@ static bool intel_lvds_get_hw_state(struct intel_encoder *encoder,
struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
enum intel_display_power_domain power_domain;
u32 tmp;
bool ret;
power_domain = intel_display_port_power_domain(encoder);
if (!intel_display_power_is_enabled(dev_priv, power_domain))
if (!intel_display_power_get_if_enabled(dev_priv, power_domain))
return false;
ret = false;
tmp = I915_READ(lvds_encoder->reg);
if (!(tmp & LVDS_PORT_EN))
return false;
goto out;
if (HAS_PCH_CPT(dev))
*pipe = PORT_TO_PIPE_CPT(tmp);
else
*pipe = PORT_TO_PIPE(tmp);
return true;
ret = true;
out:
intel_display_power_put(dev_priv, power_domain);
return ret;
}
static void intel_lvds_get_config(struct intel_encoder *encoder,