This is a note to let you know that I've just added the patch titled

    drm/i915: Fix PSR programming

to the 3.13-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-i915-fix-psr-programming.patch
and it can be found in the queue-3.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 24bd9bf54d45d28089251cdf62bf14323d1aa827 Mon Sep 17 00:00:00 2001
From: Ben Widawsky <[email protected]>
Date: Tue, 4 Mar 2014 22:38:10 -0800
Subject: drm/i915: Fix PSR programming

From: Ben Widawsky <[email protected]>

commit 24bd9bf54d45d28089251cdf62bf14323d1aa827 upstream.

| 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 ed8546ac1f99b850879f07b1e9b06b42fb0a36d9
Author: Ben Widawsky <[email protected]>
Date:   Mon Nov 4 22:45:05 2013 -0800

    drm/i915/bdw: Support eDP PSR

Cc: Rodrigo Vivi <[email protected]>
Cc: Kenneth Graunke <[email protected]>
Cc: Art Runyan <[email protected]>
Reported-by: "Kumar, Kiran S" <[email protected]>
Signed-off-by: Ben Widawsky <[email protected]>
Signed-off-by: Jani Nikula <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/gpu/drm/i915/intel_dp.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1634,7 +1634,7 @@ static void intel_edp_psr_enable_source(
                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);


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.13/drm-i915-fix-psr-programming.patch
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