linux-kernel - [PATCH 1/1] iio: gyro: bmg160: fix endianness when reading axes

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>] [day] [month] [year] [list]

Message-Id: <1459185271-18514-1-git-send-email-irina.tirdea@intel.com>
Date:	Mon, 28 Mar 2016 20:14:31 +0300
From:	Irina Tirdea <irina.tirdea@...el.com>
To:	Jonathan Cameron <jic23@...nel.org>, linux-iio@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, Hartmut Knaack <knaack.h@....de>,
	Lars-Peter Clausen <lars@...afoo.de>,
	Peter Meerwald <pmeerw@...erw.net>,
	Markus Pargmann <mpa@...gutronix.de>,
	Irina Tirdea <irina.tirdea@...el.com>
Subject: [PATCH 1/1] 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@...el.com>
---
 drivers/iio/gyro/bmg160_core.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/gyro/bmg160_core.c b/drivers/iio/gyro/bmg160_core.c
index bbce3b0..295cf1d 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);
@@ -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						\
-- 
1.9.1