[PATCH 1/6] led-uclass: do not create fallback label for top-level node

[Rasmus Villemoes]

Many existing drivers, and led-uclass itself, rely on uc_plat->label
being NULL for the device representing the top node, as opposed to the
child nodes representing individual LEDs. This means that the drivers
whose .probe methods rely on this were broken by 83c63f0d1185 ("led:
Move OF "label" property parsing to core"), and also that the top node
wrongly shows up with 'led list'. Some drivers have since been fixed
up individually, e.g.

e3aa76644c2a "led: gpio: Check device compatible string to determine the top level node"
01074697801b "led: gpio: Use NOP uclass driver for top-level node"
910b01c27c04 "drivers: led: bcm6753: do not use null label to find the top"

Binding the same driver to the top node as to the individual child
nodes is arguably wrong, and the approach of using a UCLASS_NOP driver
for the top node is probably better.

But as a temporary work-around, we can use a heuristic that only sets
the label to the fallback value derived from the node name if the node
does not have a "compatible" property - i.e., if it has been bound to
the LED driver explicitly via device_bind_driver_to_node() [similar to
what e3aa76644c2a did, but that then vanished with the next commit.]

Fixes: 83c63f0d1185 ("led: Move OF "label" property parsing to core")
Signed-off-by: Rasmus Villemoes <rasmus.villemoes at prevas.dk>
---
 drivers/led/led-uclass.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/led/led-uclass.c b/drivers/led/led-uclass.c
index 68ca3c2970..5a5d07b9a7 100644
--- a/drivers/led/led-uclass.c
+++ b/drivers/led/led-uclass.c
@@ -72,7 +72,7 @@ static int led_post_bind(struct udevice *dev)
 	const char *default_state;
 
 	uc_plat->label = dev_read_string(dev, "label");
-	if (!uc_plat->label)
+	if (!uc_plat->label && !dev_read_string(dev, "compatible"))
 		uc_plat->label = ofnode_get_name(dev_ofnode(dev));
 
 	uc_plat->default_state = LEDST_COUNT;
-- 
2.40.1.1.g1c60b9335d