This is a note to let you know that I've just added the patch titled
iio: accel: bmc150: Don't make the remove function of the second
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-testing 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 be merged to the staging-next branch sometime soon,
after it passes testing, and the merge window is open.
If you have any questions about this process, please let me know.
>From f407e2dca0f559621114eeaf657880d83f237fbd Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@xxxxxxxxxx>
Date: Sun, 23 May 2021 19:00:56 +0200
Subject: iio: accel: bmc150: Don't make the remove function of the second
accelerometer unregister itself
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@xxxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
---
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(-)
diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c
index c526d83f14d5..1aec873bee03 100644
--- a/drivers/iio/accel/bmc150-accel-core.c
+++ b/drivers/iio/accel/bmc150-accel-core.c
@@ -1811,11 +1811,11 @@ struct i2c_client *bmc150_get_second_device(struct i2c_client *client)
}
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);
diff --git a/drivers/iio/accel/bmc150-accel-i2c.c b/drivers/iio/accel/bmc150-accel-i2c.c
index 69f709319484..2afaae0294ee 100644
--- 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_client *client,
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
diff --git a/drivers/iio/accel/bmc150-accel.h b/drivers/iio/accel/bmc150-accel.h
index 6024f15b9700..e30c1698f6fb 100644
--- a/drivers/iio/accel/bmc150-accel.h
+++ b/drivers/iio/accel/bmc150-accel.h
@@ -18,7 +18,7 @@ int bmc150_accel_core_probe(struct device *dev, struct regmap *regmap, int irq,
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;
--
2.32.0
