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

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
This commit is contained in:
Imre Deak 2016-02-12 18:55:21 +02:00
parent 5b0921748c
commit ecb2448218
1 changed files with 11 additions and 3 deletions

View File

@ -76,22 +76,30 @@ static bool intel_lvds_get_hw_state(struct intel_encoder *encoder,
struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base); struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
enum intel_display_power_domain power_domain; enum intel_display_power_domain power_domain;
u32 tmp; u32 tmp;
bool ret;
power_domain = intel_display_port_power_domain(encoder); 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; return false;
ret = false;
tmp = I915_READ(lvds_encoder->reg); tmp = I915_READ(lvds_encoder->reg);
if (!(tmp & LVDS_PORT_EN)) if (!(tmp & LVDS_PORT_EN))
return false; goto out;
if (HAS_PCH_CPT(dev)) if (HAS_PCH_CPT(dev))
*pipe = PORT_TO_PIPE_CPT(tmp); *pipe = PORT_TO_PIPE_CPT(tmp);
else else
*pipe = PORT_TO_PIPE(tmp); *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, static void intel_lvds_get_config(struct intel_encoder *encoder,