During DP AUX communication we might time out 1 jiffy too early, because the calculated expiry jiffy value is one less than needed. This is only one reason for false DP AUX timeouts. For a complete solution we also need the following fix, which is now queued for mainline: http://marc.info/?l=linux-kernel&m=136748515710837&w=2 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=64133 Signed-off-by: Imre Deak <imre.deak at intel.com> --- drivers/gpu/drm/i915/intel_dp.c | 2 +- drivers/gpu/drm/i915/intel_i2c.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 3426a61..8cdc3d7 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -276,7 +276,7 @@ intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq) #define C (((status = I915_READ_NOTRACE(ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0) if (has_aux_irq) done = wait_event_timeout(dev_priv->gmbus_wait_queue, C, - msecs_to_jiffies(10)); + msecs_to_jiffies_timeout(10)); else done = wait_for_atomic(C, 10) == 0; if (!done) diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c index 98cd8535..639fe19 100644 --- a/drivers/gpu/drm/i915/intel_i2c.c +++ b/drivers/gpu/drm/i915/intel_i2c.c @@ -263,7 +263,8 @@ gmbus_wait_idle(struct drm_i915_private *dev_priv) /* Important: The hw handles only the first bit, so set only one! */ I915_WRITE(GMBUS4 + reg_offset, GMBUS_IDLE_EN); - ret = wait_event_timeout(dev_priv->gmbus_wait_queue, C, 10); + ret = wait_event_timeout(dev_priv->gmbus_wait_queue, C, + msecs_to_jiffies_timeout(10)); I915_WRITE(GMBUS4 + reg_offset, 0); -- 1.8.1.2
