From 26a91555bd27b0672ab4efaf4de04fe7321540dc Mon Sep 17 00:00:00 2001 From: Mika Kahola Date: Tue, 18 Aug 2015 14:37:02 +0300 Subject: [PATCH] drm/i915: DVO pixel clock check MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It is possible the we request to have a mode that has higher pixel clock than our HW can support. This patch checks if requested pixel clock is lower than the one supported by the HW. The requested mode is discarded if we cannot support the requested pixel clock. This patch applies to DVO. V2: - removed computation for max pixel clock V3: - cleanup by removing unnecessary lines V4: - clock check against max dotclock moved inside 'if (fixed_mode)' V5: - dot clock check against fixed_mode clock when available Signed-off-by: Mika Kahola Reviewed-by: Ville Syrjälä Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_dvo.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c index dc532bb61d22..c80fe1f49ede 100644 --- a/drivers/gpu/drm/i915/intel_dvo.c +++ b/drivers/gpu/drm/i915/intel_dvo.c @@ -201,6 +201,8 @@ intel_dvo_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode) { struct intel_dvo *intel_dvo = intel_attached_dvo(connector); + int max_dotclk = to_i915(connector->dev)->max_dotclk_freq; + int target_clock = mode->clock; if (mode->flags & DRM_MODE_FLAG_DBLSCAN) return MODE_NO_DBLESCAN; @@ -212,8 +214,13 @@ intel_dvo_mode_valid(struct drm_connector *connector, return MODE_PANEL; if (mode->vdisplay > intel_dvo->panel_fixed_mode->vdisplay) return MODE_PANEL; + + target_clock = intel_dvo->panel_fixed_mode->clock; } + if (target_clock > max_dotclk) + return MODE_CLOCK_HIGH; + return intel_dvo->dev.dev_ops->mode_valid(&intel_dvo->dev, mode); }