i2c: muxes: i2c-demux-pinctrl: Use of_get_i2c_adapter_by_node()

commit 0fb118de50 upstream.

i2c-demux-pinctrl 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: 50a5ba8769 ("i2c: mux: demux-pinctrl: add driver")
Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Cc: stable@vger.kernel.org
Acked-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Herve Codina 2023-10-20 17:30:12 +02:00 committed by Greg Kroah-Hartman
parent f9a7b3b33c
commit ff0312a156
1 changed files with 1 additions and 1 deletions

View File

@ -61,7 +61,7 @@ static int i2c_demux_activate_master(struct i2c_demux_pinctrl_priv *priv, u32 ne
if (ret)
goto err;
adap = of_find_i2c_adapter_by_node(priv->chan[new_chan].parent_np);
adap = of_get_i2c_adapter_by_node(priv->chan[new_chan].parent_np);
if (!adap) {
ret = -ENODEV;
goto err_with_revert;