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

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 <[email protected]>
Cc: [email protected]
Acked-by: Peter Rosin <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
Signed-off-by: Wolfram Sang <[email protected]>

diff --git a/drivers/i2c/muxes/i2c-mux-gpmux.c b/drivers/i2c/muxes/i2c-mux-gpmux.c
index baccf4bfaf0284be021aeb744d84e1cfaefa8cea..8305661e12539b6bfff279f3165eb5d216d6a55a 100644 (file)
--- 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_adapter(struct device *dev)
                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);