[PATCH 1/3] gpio: uclass: warn when a gpio offset is already claimed

[Pranav Sanwal]

dm_gpio_request() returns -EBUSY when the requested offset is
already claimed, but gives no indication of which label is holding
it, making an offset collision opaque to debug.

Add a dev_warn() printing the label already holding the offset
alongside the newly requested label.

Signed-off-by: Pranav Sanwal <pranav.sanwal at amd.com>
---
 drivers/gpio/gpio-uclass.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-uclass.c b/drivers/gpio/gpio-uclass.c
index 7559b8dc7e2..45f7367438a 100644
--- a/drivers/gpio/gpio-uclass.c
+++ b/drivers/gpio/gpio-uclass.c
@@ -391,8 +391,12 @@ int dm_gpio_request(struct gpio_desc *desc, const char *label)
 	int ret;
 
 	uc_priv = dev_get_uclass_priv(dev);
-	if (gpio_is_claimed(uc_priv, desc->offset))
+	if (gpio_is_claimed(uc_priv, desc->offset)) {
+		dev_warn(dev, "gpio offset %u already claimed by '%s', requested label '%s'\n",
+			 desc->offset, uc_priv->name[desc->offset], label);
 		return -EBUSY;
+	}
+
 	str = strdup(label);
 	if (!str)
 		return -ENOMEM;
-- 
2.34.1