[PATCH] nvmem: qfprom: Specify LE device endianness

Stephen Boyd sboyd at codeaurora.org
Fri Nov 20 15:37:54 PST 2015


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 at codeaurora.org>
Cc: Kevin Hilman <khilman at linaro.org>
Cc: Tyler Baker <tyler.baker at linaro.org>
Cc: Simon Arlott <simon at fire.lp0.eu>
Cc: Mark Brown <broonie at kernel.org>
Signed-off-by: Stephen Boyd <sboyd at codeaurora.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




More information about the linux-arm-kernel mailing list