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

commit 3171d37b58a76e1febbf3f4af2d06234a98cf88b upstream.

i2c-mux-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: c4aee3e1b0 ("i2c: mux: pinctrl: remove platform_data")
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 17:30:11 +02:00 committed by Greg Kroah-Hartman
parent 519ff2d9fe
commit 07ec3d952a

View File

@ -62,7 +62,7 @@ static struct i2c_adapter *i2c_mux_pinctrl_parent_adapter(struct device *dev)
dev_err(dev, "Cannot parse i2c-parent\n"); dev_err(dev, "Cannot parse i2c-parent\n");
return ERR_PTR(-ENODEV); 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); of_node_put(parent_np);
if (!parent) if (!parent)
return ERR_PTR(-EPROBE_DEFER); return ERR_PTR(-EPROBE_DEFER);