[3.16.y-ckt stable] Patch "iio:st_sensors: Fix oops when probing SPI devices" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    iio:st_sensors: Fix oops when probing SPI devices

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt13.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 57a01173d13c84de74e8b704c12c849067af678c Mon Sep 17 00:00:00 2001
From: Alban Bedel <alban.bedel at avionic-design.de>
Date: Mon, 20 Apr 2015 13:57:18 +0200
Subject: iio:st_sensors: Fix oops when probing SPI devices

commit 8e71c04f863a1754f21b27fb8ecb773d680a0a80 upstream.

In SPI mode the transfer buffer is locked with a mutex. However this
mutex is only initilized after the probe, but some transfer needs to
be done in the probe.

To fix this bug we move the mutex initialization at the beginning of
the device probe.

Signed-off-by: Alban Bedel <alban.bedel at avionic-design.de>
Acked-by: Denis Ciocca <denis.ciocca at st.com>
Signed-off-by: Jonathan Cameron <jic23 at kernel.org>
[ luis: backported to 3.16:
  - use 'pdata' instead of 'press_data' in st_press_common_probe()
  - adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/iio/accel/st_accel_core.c               | 1 +
 drivers/iio/common/st_sensors/st_sensors_core.c | 2 --
 drivers/iio/gyro/st_gyro_core.c                 | 1 +
 drivers/iio/magnetometer/st_magn_core.c         | 1 +
 drivers/iio/pressure/st_pressure_core.c         | 1 +
 5 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
index a2abf7c2ce3b..36cb5139e48e 100644
--- a/drivers/iio/accel/st_accel_core.c
+++ b/drivers/iio/accel/st_accel_core.c
@@ -458,6 +458,7 @@ int st_accel_common_probe(struct iio_dev *indio_dev,

 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &accel_info;
+	mutex_init(&adata->tb.buf_lock);

 	st_sensors_power_enable(indio_dev);

diff --git a/drivers/iio/common/st_sensors/st_sensors_core.c b/drivers/iio/common/st_sensors/st_sensors_core.c
index e8b932fed70e..4cafb43f948e 100644
--- a/drivers/iio/common/st_sensors/st_sensors_core.c
+++ b/drivers/iio/common/st_sensors/st_sensors_core.c
@@ -271,8 +271,6 @@ int st_sensors_init_sensor(struct iio_dev *indio_dev,
 	struct st_sensor_data *sdata = iio_priv(indio_dev);
 	int err = 0;

-	mutex_init(&sdata->tb.buf_lock);
-
 	if (pdata)
 		err = st_sensors_set_drdy_int_pin(indio_dev, pdata);

diff --git a/drivers/iio/gyro/st_gyro_core.c b/drivers/iio/gyro/st_gyro_core.c
index ed74a9069989..bd6015d01d08 100644
--- a/drivers/iio/gyro/st_gyro_core.c
+++ b/drivers/iio/gyro/st_gyro_core.c
@@ -310,6 +310,7 @@ int st_gyro_common_probe(struct iio_dev *indio_dev,

 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &gyro_info;
+	mutex_init(&gdata->tb.buf_lock);

 	st_sensors_power_enable(indio_dev);

diff --git a/drivers/iio/magnetometer/st_magn_core.c b/drivers/iio/magnetometer/st_magn_core.c
index 4d55151893af..04ec7bae5655 100644
--- a/drivers/iio/magnetometer/st_magn_core.c
+++ b/drivers/iio/magnetometer/st_magn_core.c
@@ -362,6 +362,7 @@ int st_magn_common_probe(struct iio_dev *indio_dev,

 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &magn_info;
+	mutex_init(&mdata->tb.buf_lock);

 	st_sensors_power_enable(indio_dev);

diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
index cd7e01f3a93b..1aa7c18471a8 100644
--- a/drivers/iio/pressure/st_pressure_core.c
+++ b/drivers/iio/pressure/st_pressure_core.c
@@ -395,6 +395,7 @@ int st_press_common_probe(struct iio_dev *indio_dev,

 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &press_info;
+	mutex_init(&pdata->tb.buf_lock);

 	st_sensors_power_enable(indio_dev);