From eceb784cec4dc0fcc2993d9ee4a7c0d111ada80a Mon Sep 17 00:00:00 2001 From: Zhenyu Wang Date: Mon, 25 Jan 2010 10:35:16 +0800 Subject: [PATCH] drm/i915: disable hotplug detect before Ironlake CRT detect This tries to fix CRT detect loop hang seen on some Ironlake form factor, to clear up hotplug detect state before taking CRT detect to make sure next hotplug detect cycle is consistent. Cc: Stable Team Signed-off-by: Zhenyu Wang Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/intel_crt.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c index ddefc871edfe..79dd4026586f 100644 --- a/drivers/gpu/drm/i915/intel_crt.c +++ b/drivers/gpu/drm/i915/intel_crt.c @@ -157,6 +157,9 @@ static bool intel_ironlake_crt_detect_hotplug(struct drm_connector *connector) adpa = I915_READ(PCH_ADPA); adpa &= ~ADPA_CRT_HOTPLUG_MASK; + /* disable HPD first */ + I915_WRITE(PCH_ADPA, adpa); + (void)I915_READ(PCH_ADPA); adpa |= (ADPA_CRT_HOTPLUG_PERIOD_128 | ADPA_CRT_HOTPLUG_WARMUP_10MS | -- 2.30.2