From: Hans de Goede hdegoede@redhat.com
commit f407e2dca0f559621114eeaf657880d83f237fbd upstream.
On machines with dual accelerometers described in a single ACPI fwnode, the bmc150_accel_probe() instantiates a second i2c-client for the second accelerometer.
A pointer to this manually instantiated second i2c-client is stored inside the iio_dev's private-data through bmc150_set_second_device(), so that the i2c-client can be unregistered from bmc150_accel_remove().
Before this commit bmc150_set_second_device() took only 1 argument so it would store the pointer in private-data of the iio_dev belonging to the manually instantiated i2c-client, leading to the bmc150_accel_remove() call for the second_dev trying to unregister *itself* while it was being removed, leading to a deadlock and rmmod hanging.
Change bmc150_set_second_device() to take 2 arguments: 1. The i2c-client which is instantiating the second i2c-client for the 2nd accelerometer and 2. The second-device pointer itself (which also is an i2c-client).
This will store the second_device pointer in the private data of the iio_dev belonging to the (ACPI instantiated) i2c-client for the first accelerometer and will make bmc150_accel_remove() unregister the second_device i2c-client when called for the first client, avoiding the deadlock.
Fixes: 5bfb3a4bd8f6 ("iio: accel: bmc150: Check for a second ACPI device for BOSC0200") Cc: Jeremy Cline jeremy@jcline.org Signed-off-by: Hans de Goede hdegoede@redhat.com Reviewed-by: Andy Shevchenko andy.shevchenko@gmail.com Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/iio/accel/bmc150-accel-core.c | 4 ++-- drivers/iio/accel/bmc150-accel-i2c.c | 2 +- drivers/iio/accel/bmc150-accel.h | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/iio/accel/bmc150-accel-core.c +++ b/drivers/iio/accel/bmc150-accel-core.c @@ -1816,11 +1816,11 @@ struct i2c_client *bmc150_get_second_dev } EXPORT_SYMBOL_GPL(bmc150_get_second_device);
-void bmc150_set_second_device(struct i2c_client *client) +void bmc150_set_second_device(struct i2c_client *client, struct i2c_client *second_dev) { struct bmc150_accel_data *data = iio_priv(i2c_get_clientdata(client));
- data->second_device = client; + data->second_device = second_dev; } EXPORT_SYMBOL_GPL(bmc150_set_second_device);
--- a/drivers/iio/accel/bmc150-accel-i2c.c +++ b/drivers/iio/accel/bmc150-accel-i2c.c @@ -70,7 +70,7 @@ static int bmc150_accel_probe(struct i2c
second_dev = i2c_acpi_new_device(&client->dev, 1, &board_info); if (!IS_ERR(second_dev)) - bmc150_set_second_device(second_dev); + bmc150_set_second_device(client, second_dev); } #endif
--- a/drivers/iio/accel/bmc150-accel.h +++ b/drivers/iio/accel/bmc150-accel.h @@ -18,7 +18,7 @@ int bmc150_accel_core_probe(struct devic const char *name, bool block_supported); int bmc150_accel_core_remove(struct device *dev); struct i2c_client *bmc150_get_second_device(struct i2c_client *second_device); -void bmc150_set_second_device(struct i2c_client *second_device); +void bmc150_set_second_device(struct i2c_client *client, struct i2c_client *second_dev); extern const struct dev_pm_ops bmc150_accel_pm_ops; extern const struct regmap_config bmc150_regmap_conf;