[3.13.y.z extended stable] Patch "spi: orion: fix incorrect handling of cell-index DT property" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    spi: orion: fix incorrect handling of cell-index DT property

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.7.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 795b6127f7f70a800d8ae5ff60d6829ab909e98f Mon Sep 17 00:00:00 2001
From: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Date: Sun, 27 Jul 2014 23:53:19 +0200
Subject: spi: orion: fix incorrect handling of cell-index DT property

commit e06871cd2c92e5c65d7ca1d32866b4ca5dd4ac30 upstream.

In commit f814f9ac5a81 ("spi/orion: add device tree binding"), Device
Tree support was added to the spi-orion driver. However, this commit
reads the "cell-index" property, without taking into account the fact
that DT properties are big-endian encoded.

Since most of the platforms using spi-orion with DT have apparently
not used anything but cell-index = <0>, the problem was not
visible. But as soon as one starts using cell-index = <1>, the problem
becomes clearly visible, as the master->bus_num gets a wrong value
(actually it gets the value 0, which conflicts with the first bus that
has cell-index = <0>).

This commit fixes that by using of_property_read_u32() to read the
property value, which does the appropriate endianness conversion when
needed.

Fixes: f814f9ac5a81 ("spi/orion: add device tree binding")
Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth at gmail.com>
Signed-off-by: Mark Brown <broonie at linaro.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/spi/spi-orion.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/spi/spi-orion.c b/drivers/spi/spi-orion.c
index 744841e..fbc9ac9 100644
--- a/drivers/spi/spi-orion.c
+++ b/drivers/spi/spi-orion.c
@@ -404,8 +404,6 @@ static int orion_spi_probe(struct platform_device *pdev)
 	struct resource *r;
 	unsigned long tclk_hz;
 	int status = 0;
-	const u32 *iprop;
-	int size;

 	master = spi_alloc_master(&pdev->dev, sizeof(*spi));
 	if (master == NULL) {
@@ -416,10 +414,10 @@ static int orion_spi_probe(struct platform_device *pdev)
 	if (pdev->id != -1)
 		master->bus_num = pdev->id;
 	if (pdev->dev.of_node) {
-		iprop = of_get_property(pdev->dev.of_node, "cell-index",
-					&size);
-		if (iprop && size == sizeof(*iprop))
-			master->bus_num = *iprop;
+		u32 cell_index;
+		if (!of_property_read_u32(pdev->dev.of_node, "cell-index",
+					  &cell_index))
+			master->bus_num = cell_index;
 	}

 	/* we support only mode 0, and no options */
--
1.9.1