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

    drm/tegra: dpaux: Fix transfers larger than 4 bytes

to the 4.1-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-tegra-dpaux-fix-transfers-larger-than-4-bytes.patch
and it can be found in the queue-4.1 subdirectory.

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


>From 3c1dae0a07c651526f8e878d223a88f82caa5a50 Mon Sep 17 00:00:00 2001
From: Thierry Reding <[email protected]>
Date: Thu, 11 Jun 2015 18:33:48 +0200
Subject: drm/tegra: dpaux: Fix transfers larger than 4 bytes

From: Thierry Reding <[email protected]>

commit 3c1dae0a07c651526f8e878d223a88f82caa5a50 upstream.

The DPAUX read/write FIFO registers aren't sequential in the register
space, causing transfers larger than 4 bytes to cause accesses to non-
existing FIFO registers.

Fixes: 6b6b604215c6 ("drm/tegra: Add eDP support")
Signed-off-by: Thierry Reding <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/gpu/drm/tegra/dpaux.c |   18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

--- a/drivers/gpu/drm/tegra/dpaux.c
+++ b/drivers/gpu/drm/tegra/dpaux.c
@@ -72,34 +72,32 @@ static inline void tegra_dpaux_writel(st
 static void tegra_dpaux_write_fifo(struct tegra_dpaux *dpaux, const u8 *buffer,
                                   size_t size)
 {
-       unsigned long offset = DPAUX_DP_AUXDATA_WRITE(0);
        size_t i, j;
 
-       for (i = 0; i < size; i += 4) {
-               size_t num = min_t(size_t, size - i, 4);
+       for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
+               size_t num = min_t(size_t, size - i * 4, 4);
                unsigned long value = 0;
 
                for (j = 0; j < num; j++)
-                       value |= buffer[i + j] << (j * 8);
+                       value |= buffer[i * 4 + j] << (j * 8);
 
-               tegra_dpaux_writel(dpaux, value, offset++);
+               tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXDATA_WRITE(i));
        }
 }
 
 static void tegra_dpaux_read_fifo(struct tegra_dpaux *dpaux, u8 *buffer,
                                  size_t size)
 {
-       unsigned long offset = DPAUX_DP_AUXDATA_READ(0);
        size_t i, j;
 
-       for (i = 0; i < size; i += 4) {
-               size_t num = min_t(size_t, size - i, 4);
+       for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
+               size_t num = min_t(size_t, size - i * 4, 4);
                unsigned long value;
 
-               value = tegra_dpaux_readl(dpaux, offset++);
+               value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXDATA_READ(i));
 
                for (j = 0; j < num; j++)
-                       buffer[i + j] = value >> (j * 8);
+                       buffer[i * 4 + j] = value >> (j * 8);
        }
 }
 


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

queue-4.1/drm-tegra-dpaux-fix-transfers-larger-than-4-bytes.patch
queue-4.1/drm-bridge-ptn3460-include-linux-gpio-consumer.h.patch
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