[PATCH v4 1/3] leds: Require valid fwnode pointer for composing name

From: Alexander Dahl
Date: Fri Sep 11 2020 - 12:10:07 EST

The function 'led_compose_name()' is called in
'led_classdev_register_ext(()' only and in its implementation it always
parses the fwnode passed with the init_data struct. If there's no
fwnode, EINVAL is returned and 'led_classdev_register_ext()' returns

If this is detected early the same fallback mechanism can be used , as
if init_data itself is NULL. This will allow drivers to pass fully
populated 'init_data' or sparse initialized 'init_data' with a NULL
fwnode in a more elegant way with only one function call.

Fixes: bb4e9af0348d ("leds: core: Add support for composing LED class device names")
Suggested-by: Pavel Machek <pavel@xxxxxx>
Signed-off-by: Alexander Dahl <post@xxxxxxxxxxx>

* added this patch to series (Suggested-by: Pavel Machek)

drivers/leds/led-class.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index cc3929f858b6..3da50c7ecfe7 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -346,7 +346,7 @@ int led_classdev_register_ext(struct device *parent,
const char *proposed_name = composed_name;
int ret;

- if (init_data) {
+ if (init_data && init_data->fwnode) {
if (init_data->devname_mandatory && !init_data->devicename) {
dev_err(parent, "Mandatory device name is missing");
return -EINVAL;