Patch "iio: gyro: bmg160: fix endianness when reading axes" has been added to the 4.4-stable tree

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 the 4.4-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:
iio-gyro-bmg160-fix-endianness-when-reading-axes.patch
and it can be found in the queue-4.4 subdirectory.

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

From: Irina Tirdea <[email protected]>
Date: Tue, 29 Mar 2016 15:37:30 +0300
Subject: iio: gyro: bmg160: fix endianness when reading axes

From: Irina Tirdea <[email protected]>

commit 95e7ff034175db7d8aefabe7716c4d42bea24fde upstream.

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").

---
 drivers/iio/gyro/bmg160_core.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

@@ -452,7 +452,7 @@ static int bmg160_get_temp(struct bmg160
 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
 	}
 
 	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
 		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 bmg16
 		.sign = 's',						\
 		.realbits = 16,					\
 		.storagebits = 16,					\
+		.endianness = IIO_LE,					\
 	},								\
 	.event_spec = &bmg160_event,					\
 	.num_event_specs = 1						\

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

queue-4.4/iio-gyro-bmg160-fix-buffer-read-values.patch queue-4.4/iio-gyro-bmg160-fix-endianness-when-reading-axes.patch queue-4.4/iio-accel-bmc150-fix-endianness-when-reading-axes.patch