patch "iio: gyro: bmg160: fix endianness when reading axes" added to staging-linus

patch "iio: gyro: bmg160: fix endianness when reading axes" added to staging-linus

[gregkh]

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

    iio: gyro: bmg160: fix endianness when reading axes

to my staging git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


>From 95e7ff034175db7d8aefabe7716c4d42bea24fde Mon Sep 17 00:00:00 2001
From: Irina Tirdea <irina.tirdea@intel.com>
Date: Tue, 29 Mar 2016 15:37:30 +0300
Subject: iio: gyro: bmg160: fix endianness when reading axes

For big endian platforms, reading the axes will return
invalid values.

The device stores each axis value in a 16 bit little
endian register. The driver uses regmap_read_bulk to get
the axis value, resulting in a 16 bit little endian value.
This needs to be converted to cpu endianness to work
on big endian platforms.

Fix endianness for big endian platforms by converting
the values for the axes read from little endian to
cpu.

This is also partially fixed in commit 82d8e5da1a33 ("iio:
accel: bmg160: optimize transfers in trigger handler").

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---
 drivers/iio/gyro/bmg160_core.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/gyro/bmg160_core.c b/drivers/iio/gyro/bmg160_core.c
index bbce3b09ac45..8d3f0b36bc1c 100644
--- a/drivers/iio/gyro/bmg160_core.c
+++ b/drivers/iio/gyro/bmg160_core.c
@@ -452,7 +452,7 @@ static int bmg160_get_temp(struct bmg160_data *data, int *val)
 static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
 {
 	int ret;
-	unsigned int raw_val;
+	__le16 raw_val;
 
 	mutex_lock(&data->mutex);
 	ret = bmg160_set_power_state(data, true);
@@ -462,7 +462,7 @@ static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
 	}
 
 	ret = regmap_bulk_read(data->regmap, BMG160_AXIS_TO_REG(axis), &raw_val,
-			       2);
+			       sizeof(raw_val));
 	if (ret < 0) {
 		dev_err(data->dev, "Error reading axis %d\n", axis);
 		bmg160_set_power_state(data, false);
@@ -470,7 +470,7 @@ static int bmg160_get_axis(struct bmg160_data *data, int axis, int *val)
 		return ret;
 	}
 
-	*val = sign_extend32(raw_val, 15);
+	*val = sign_extend32(le16_to_cpu(raw_val), 15);
 	ret = bmg160_set_power_state(data, false);
 	mutex_unlock(&data->mutex);
 	if (ret < 0)
@@ -733,6 +733,7 @@ static const struct iio_event_spec bmg160_event = {
 		.sign = 's',						\
 		.realbits = 16,					\
 		.storagebits = 16,					\
+		.endianness = IIO_LE,					\
 	},								\
 	.event_spec = &bmg160_event,					\
 	.num_event_specs = 1						\
-- 
2.8.0