Re: [PATCH v2 3/3] i2c: muxes: i2c-mux-gpmux: Use of_get_i2c_adapter_by_node()

From: Greg Kroah-Hartman
Date: Thu Oct 19 2023 - 14:00:58 EST


On Thu, Oct 19, 2023 at 12:10:16PM +0200, Herve Codina wrote:
> 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>
> Acked-by: Peter Rosin <peda@xxxxxxxxxx>
> ---
> drivers/i2c/muxes/i2c-mux-gpmux.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him
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