This is a note to let you know that I've just added the patch titled
i2c: muxes: i2c-mux-gpmux: Use of_get_i2c_adapter_by_node()
to the 5.15-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:
i2c-muxes-i2c-mux-gpmux-use-of_get_i2c_adapter_by_node.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 3dc0ec46f6e7511fc4fdf6b6cda439382bc957f1 Mon Sep 17 00:00:00 2001
From: Herve Codina <herve.codina@xxxxxxxxxxx>
Date: Fri, 20 Oct 2023 17:30:13 +0200
Subject: i2c: muxes: i2c-mux-gpmux: Use of_get_i2c_adapter_by_node()
From: Herve Codina <herve.codina@xxxxxxxxxxx>
commit 3dc0ec46f6e7511fc4fdf6b6cda439382bc957f1 upstream.
i2c-mux-gpmux uses the pair of_find_i2c_adapter_by_node() /
i2c_put_adapter(). These pair alone is not correct to properly lock the
I2C parent adapter.
Indeed, i2c_put_adapter() decrements the module refcount while
of_find_i2c_adapter_by_node() does not increment it. This leads to an
underflow of the parent module refcount.
Use the dedicated function, of_get_i2c_adapter_by_node(), to handle
correctly the module refcount.
Fixes: ac8498f0ce53 ("i2c: i2c-mux-gpmux: new driver")
Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Acked-by: Peter Rosin <peda@xxxxxxxxxx>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/i2c/muxes/i2c-mux-gpmux.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/i2c/muxes/i2c-mux-gpmux.c
+++ b/drivers/i2c/muxes/i2c-mux-gpmux.c
@@ -52,7 +52,7 @@ static struct i2c_adapter *mux_parent_ad
dev_err(dev, "Cannot parse i2c-parent\n");
return ERR_PTR(-ENODEV);
}
- parent = of_find_i2c_adapter_by_node(parent_np);
+ parent = of_get_i2c_adapter_by_node(parent_np);
of_node_put(parent_np);
if (!parent)
return ERR_PTR(-EPROBE_DEFER);
Patches currently in stable-queue which might be from herve.codina@xxxxxxxxxxx are
queue-5.15/i2c-muxes-i2c-demux-pinctrl-use-of_get_i2c_adapter_by_node.patch
queue-5.15/i2c-muxes-i2c-mux-pinctrl-use-of_get_i2c_adapter_by_node.patch
queue-5.15/i2c-muxes-i2c-mux-gpmux-use-of_get_i2c_adapter_by_node.patch
