Matching anything that just happens to have the sought-for label as a prefix is wrong. For example, if the board designer has designated 10 lines for debug purposes, named "debug1" through "debug10", and we are looking up "debug1", if debug10 happens to be met first during the iteration we'd wrongly return that.
In theory, this can break existing users that could rely on this quirk, but OTOH keeping the current broken semantics can cause a lot of grief for people hitting this in the future and not understanding why they don't find the line they expect. Considering how few in-tree defconfigs currently set DM_GPIO_LOOKUP_LABEL (ignoring sandbox, only four "real" boards), let's fix it before the use becomes more widespread.
Signed-off-by: Rasmus Villemoes rasmus.villemoes@prevas.dk --- drivers/gpio/gpio-uclass.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c index 0ed32b7217..01342202fa 100644 --- a/drivers/gpio/gpio-uclass.c +++ b/drivers/gpio/gpio-uclass.c @@ -91,15 +91,13 @@ static int gpio_to_device(unsigned int gpio, struct gpio_desc *desc) static int dm_gpio_lookup_label(const char *name, struct gpio_dev_priv *uc_priv, ulong *offset) { - int len; int i;
*offset = -1; - len = strlen(name); for (i = 0; i < uc_priv->gpio_count; i++) { if (!uc_priv->name[i]) continue; - if (!strncmp(name, uc_priv->name[i], len)) { + if (!strcmp(name, uc_priv->name[i])) { *offset = i; return 0; }