drm/i915: Fix PSR programming

| has a higher precedence than ?. Therefore, the calculation doesn't do
at all what you would expect. Thanks to Ken for convincing me that this
was indeed the issue. Send me back to C programmer school, please.

I'm sort of surprised PSR was continuing to work for people. It should
be broken IMO (and it was broken for me, but I had assumed it never
worked).

Regression from:
commit bcaaf0d56191229700f19543f39e245cb454ee49
Author: Ben Widawsky <benjamin.widawsky@intel.com>
Date:   Mon Nov 4 22:45:05 2013 -0800

    drm/i915/bdw: Support eDP PSR

Cc: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Cc: Kenneth Graunke <kenneth.w.graunke@intel.com>
Cc: Art Runyan <arthur.j.runyan@intel.com>
Reported-by: "Kumar, Kiran S" <kiran.s.kumar@intel.com>
Cc: stable@vger.kernel.org [v3.13+]
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 57552eb386b0b1b6d735a7fb0f9b770405e5f411..41bdac44dfc1e32abe3b2466aa1b34f126e8548f 100644 (file)
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1639,7 +1639,7 @@ static void intel_edp_psr_enable_source(struct intel_dp *intel_dp)
                val |= EDP_PSR_LINK_DISABLE;
 
        I915_WRITE(EDP_PSR_CTL(dev), val |
-                  IS_BROADWELL(dev) ? 0 : link_entry_time |
+                  (IS_BROADWELL(dev) ? 0 : link_entry_time) |
                   max_sleep_time << EDP_PSR_MAX_SLEEP_TIME_SHIFT |
                   idle_frames << EDP_PSR_IDLE_FRAME_SHIFT |
                   EDP_PSR_ENABLE);