leds: bd2606mvv: Fix device child node usage in bd2606mvv_probe()

The current implementation accesses the `child` fwnode handle outside of
fwnode_for_each_available_child_node() without incrementing its
refcount. Add the missing call to `fwnode_handle_get(child)`.

The cleanup process where `child` is accessed is not right either
because a single call to `fwnode_handle_put()` is carried out in case of
an error, ignoring unasigned nodes at the point when the error happens.
Keep `child` inside of the first loop, and use the helper pointer that
receives references via `fwnode_handle_get()` to handle the child nodes
within the second loop.

Moreover, the iterated nodes are direct children of the device node,
and the `device_for_each_child_node()` macro accounts for child node
availability. By restricting `child` to live within that loop, the
scoped version of it can be used to simplify the error handling.

`fwnode_for_each_available_child_node()` is meant to access the child
nodes of an fwnode, and therefore not direct child nodes of the device
node.

Use `device_for_each_child_node_scoped()` to indicate device's direct
child nodes.

Fixes: 8325642d2757 ("leds: bd2606mvv: Driver for the Rohm 6 Channel i2c LED driver")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Link: https://lore.kernel.org/r/20240721-device_for_each_child_node-available-v2-3-f33748fd8b2d@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>

diff --git a/drivers/leds/leds-bd2606mvv.c b/drivers/leds/leds-bd2606mvv.c
index 3fda712d2f80955fb8fe1a6d03c864634e683f87..c1181a35d0f7623e4ffd78aded5e04902d6146eb 100644 (file)
--- a/drivers/leds/leds-bd2606mvv.c
+++ b/drivers/leds/leds-bd2606mvv.c
@@ -69,16 +69,14 @@ static const struct regmap_config bd2606mvv_regmap = {
 
 static int bd2606mvv_probe(struct i2c_client *client)
 {
-       struct fwnode_handle *np, *child;
        struct device *dev = &client->dev;
        struct bd2606mvv_priv *priv;
        struct fwnode_handle *led_fwnodes[BD2606_MAX_LEDS] = { 0 };
        int active_pairs[BD2606_MAX_LEDS / 2] = { 0 };
        int err, reg;
-       int i;
+       int i, j;
 
-       np = dev_fwnode(dev);
-       if (!np)
+       if (!dev_fwnode(dev))
                return -ENODEV;
 
        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
@@ -94,20 +92,18 @@ static int bd2606mvv_probe(struct i2c_client *client)
 
        i2c_set_clientdata(client, priv);
 
-       fwnode_for_each_available_child_node(np, child) {
+       device_for_each_child_node_scoped(dev, child) {
                struct bd2606mvv_led *led;
 
                err = fwnode_property_read_u32(child, "reg", &reg);
-               if (err) {
-                       fwnode_handle_put(child);
+               if (err)
                        return err;
-               }
-               if (reg < 0 || reg >= BD2606_MAX_LEDS || led_fwnodes[reg]) {
-                       fwnode_handle_put(child);
+
+               if (reg < 0 || reg >= BD2606_MAX_LEDS || led_fwnodes[reg])
                        return -EINVAL;
-               }
+
                led = &priv->leds[reg];
-               led_fwnodes[reg] = child;
+               led_fwnodes[reg] = fwnode_handle_get(child);
                active_pairs[reg / 2]++;
                led->priv = priv;
                led->led_no = reg;
@@ -130,7 +126,8 @@ static int bd2606mvv_probe(struct i2c_client *client)
                                                     &priv->leds[i].ldev,
                                                     &init_data);
                if (err < 0) {
-                       fwnode_handle_put(child);
+                       for (j = i; j < BD2606_MAX_LEDS; j++)
+                               fwnode_handle_put(led_fwnodes[j]);
                        return dev_err_probe(dev, err,
                                             "couldn't register LED %s\n",
                                             priv->leds[i].ldev.name);