linux-kernel - [PATCH] nvmem: qfprom: Specify LE device endianness

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 20 Nov 2015 15:37:54 -0800
From:	Stephen Boyd <sboyd@...eaurora.org>
To:	Srinivas Kandagatla <srinivas.kandagatla@...aro.org>,
	Maxime Ripard <maxime.ripard@...e-electrons.com>
Cc:	linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	Rajendra Nayak <rnayak@...eaurora.org>,
	Kevin Hilman <khilman@...aro.org>,
	Tyler Baker <tyler.baker@...aro.org>,
	Simon Arlott <simon@...e.lp0.eu>,
	Mark Brown <broonie@...nel.org>
Subject: [PATCH] nvmem: qfprom: Specify LE device endianness

The qfprom is a little endian device, but so far we've been
relying on the regmap mmio bus handling this for us without
explicitly stating that fact. After commit 4a98da2164cf
(regmap-mmio: Use native endianness for read/write, 2015-10-29),
the regmap mmio bus will read/write with the __raw_*() IO
accessors, instead of using the readl/writel() APIs that do
proper byte swapping for little endian devices.

So if we're running on a big endian processor and haven't
specified the endianness explicitly in the regmap config or in
DT, we're going to switch from doing little endian byte swapping
to big endian accesses without byte swapping, leading to some
confusing results. Specify the endianness explicitly so that the
regmap core properly byte swaps the accesses for us.

Cc: Rajendra Nayak <rnayak@...eaurora.org>
Cc: Kevin Hilman <khilman@...aro.org>
Cc: Tyler Baker <tyler.baker@...aro.org>
Cc: Simon Arlott <simon@...e.lp0.eu>
Cc: Mark Brown <broonie@...nel.org>
Signed-off-by: Stephen Boyd <sboyd@...eaurora.org>
---
 drivers/nvmem/qfprom.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index afb67e7eeee4..3829e5fbf8c3 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -21,6 +21,7 @@ static struct regmap_config qfprom_regmap_config = {
 	.reg_bits = 32,
 	.val_bits = 8,
 	.reg_stride = 1,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
 };

 static struct nvmem_config econfig = {
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/