drm/i915: enable lvds pin pairs before dpll on gen2

Otherwise things migt not work too well.

Breakage introduced in

commit eb1cbe4848b01f9f073064377875bc7d71eb401b
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Wed Mar 28 23:12:16 2012 +0200

    drm/i915: split PLL update code out of i9xx_crtc_mode_set

Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: stable@vger.kernel.org (for 3.5 only)
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index bc2ad348e5d8ce9e13c51b1c6dba019e0e2acc4e..c040aee1341cf2065f1ea91eb1b54fbdf54d96b8 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4191,12 +4191,6 @@ static void i8xx_update_pll(struct drm_crtc *crtc,
        POSTING_READ(DPLL(pipe));
        udelay(150);
 
-       I915_WRITE(DPLL(pipe), dpll);
-
-       /* Wait for the clocks to stabilize. */
-       POSTING_READ(DPLL(pipe));
-       udelay(150);
-
        /* The LVDS pin pair needs to be on before the DPLLs are enabled.
         * This is an exception to the general rule that mode_set doesn't turn
         * things on.
@@ -4204,6 +4198,12 @@ static void i8xx_update_pll(struct drm_crtc *crtc,
        if (intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS))
                intel_update_lvds(crtc, clock, adjusted_mode);
 
+       I915_WRITE(DPLL(pipe), dpll);
+
+       /* Wait for the clocks to stabilize. */
+       POSTING_READ(DPLL(pipe));
+       udelay(150);
+
        /* The pixel multiplier can only be updated once the
         * DPLL is enabled and the clocks are stable.
         *