From bb66c5122b4300b475b585fffb811311f39f5431 Mon Sep 17 00:00:00 2001 From: Zhao Yakui Date: Thu, 10 Sep 2009 15:45:49 +0800 Subject: [PATCH] drm/i915: Write zero to DPLL_MD Reg for non-SDVO output When the output device is LVDS, maybe the pixel clock of adjusted_mode will be less than that in mode. In such case it will set the incorrect multipler factor in DPLL_MD register. So the dpll_md_reg will be reset when the output type is non-SDVO https://bugs.freedesktop.org/show_bug.cgi?id=22761 Signed-off-by: Zhao Yakui Reviewd-by: Eric Anholt Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/intel_display.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 155719ff99d1..cb5305ccb15c 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2652,9 +2652,12 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc, udelay(150); if (IS_I965G(dev) && !IS_IGDNG(dev)) { - sdvo_pixel_multiply = adjusted_mode->clock / mode->clock; - I915_WRITE(dpll_md_reg, (0 << DPLL_MD_UDI_DIVIDER_SHIFT) | + if (is_sdvo) { + sdvo_pixel_multiply = adjusted_mode->clock / mode->clock; + I915_WRITE(dpll_md_reg, (0 << DPLL_MD_UDI_DIVIDER_SHIFT) | ((sdvo_pixel_multiply - 1) << DPLL_MD_UDI_MULTIPLIER_SHIFT)); + } else + I915_WRITE(dpll_md_reg, 0); } else { /* write it again -- the BIOS does, after all */ I915_WRITE(dpll_reg, dpll); -- 2.20.1