From fe97fd7eb87255883ae1da2d726baaae2b50e80d Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Fri, 12 Feb 2016 18:55:19 +0200 Subject: [PATCH] drm/i915/dsi: 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 Reviewed-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-11-git-send-email-imre.deak@intel.com (cherry picked from commit 3f3f42b887fbffc3353e44ef9f32456c19ae4280) Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/intel_dsi.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c index 44742fa2f616..0193c62a53ef 100644 --- a/drivers/gpu/drm/i915/intel_dsi.c +++ b/drivers/gpu/drm/i915/intel_dsi.c @@ -664,13 +664,16 @@ static bool intel_dsi_get_hw_state(struct intel_encoder *encoder, struct drm_device *dev = encoder->base.dev; enum intel_display_power_domain power_domain; enum port port; + bool ret; DRM_DEBUG_KMS("\n"); 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; + /* XXX: this only works for one DSI output */ for_each_dsi_port(port, intel_dsi->ports) { i915_reg_t ctrl_reg = IS_BROXTON(dev) ? @@ -691,12 +694,16 @@ static bool intel_dsi_get_hw_state(struct intel_encoder *encoder, if (dpi_enabled || (func & CMD_MODE_DATA_WIDTH_MASK)) { if (I915_READ(MIPI_DEVICE_READY(port)) & DEVICE_READY) { *pipe = port == PORT_A ? PIPE_A : PIPE_B; - return true; + ret = true; + + goto out; } } } +out: + intel_display_power_put(dev_priv, power_domain); - return false; + return ret; } static void intel_dsi_get_config(struct intel_encoder *encoder, -- 2.20.1