From: H. Nikolaus Schaller hns@goldelico.com
[ Upstream commit c1087c29e96a48e9080377e168d35dcb52fb068b ]
Commit 96f524105b9c ("leds: tca6507: use fwnode API instead of OF")
changed to fwnode API but did not take into account that a missing property "linux,default-trigger" now seems to return an error and as a side effect sets value to -1. This seems to be different from of_get_property() which always returned NULL in any case of error.
Neglecting this side-effect leads to
[ 11.201965] Unable to handle kernel paging request at virtual address ffffffff when read
in the strcmp() of led_trigger_set_default() if there is no led-trigger defined in the DTS.
I don't know if this was recently introduced somewhere in the fwnode lib or if the effect was missed in initial testing. Anyways it seems to be a bug to ignore the error return value of an optional value here in the driver.
Fixes: 96f524105b9c ("leds: tca6507: use fwnode API instead of OF") Signed-off-by: H. Nikolaus Schaller hns@goldelico.com Acked-by: Pavel Machek pavel@ucw.cz Reviewed-by: Marek Behún kabel@kernel.org Signed-off-by: Lee Jones lee@kernel.org Link: https://lore.kernel.org/r/cbae7617db83113de726fcc423a805ebaa1bfca6.168043397... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/leds/leds-tca6507.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/leds/leds-tca6507.c b/drivers/leds/leds-tca6507.c index 225b765830bdc..caad9d3e0eac8 100644 --- a/drivers/leds/leds-tca6507.c +++ b/drivers/leds/leds-tca6507.c @@ -696,8 +696,9 @@ tca6507_led_dt_init(struct device *dev) if (fwnode_property_read_string(child, "label", &led.name)) led.name = fwnode_get_name(child);
- fwnode_property_read_string(child, "linux,default-trigger", - &led.default_trigger); + if (fwnode_property_read_string(child, "linux,default-trigger", + &led.default_trigger)) + led.default_trigger = NULL;
led.flags = 0; if (fwnode_property_match_string(child, "compatible",