led: Fix next Coverity scan error
The following was reported by Coverity scan:
*** CID 542488: Control flow issues (NO_EFFECT)
/drivers/led/led-uclass.c: 277 in led_get_function_name()
271 return uc_plat->label;
272
273 /* Now try to detect function label name */
274 func = dev_read_string(dev, "function");
275 cp = dev_read_u32(dev, "color", &color);
276 // prevent coverity scan error CID 541279: (TAINTED_SCALAR)
>>> CID 542488: Control flow issues (NO_EFFECT)
>>> This less-than-zero comparison of an unsigned value is never true. "color < 0U".
277 if (color < LED_COLOR_ID_WHITE || color >= LED_COLOR_ID_MAX)
278 cp = -EINVAL;
279
Fix it.
Addresses-Coverity-ID: 542488
Link: https://lists.denx.de/pipermail/u-boot/2025-February/581567.html
Signed-off-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
diff --git a/drivers/led/led-uclass.c b/drivers/led/led-uclass.c
index 22f61d1..edcdeee 100644
--- a/drivers/led/led-uclass.c
+++ b/drivers/led/led-uclass.c
@@ -273,8 +273,12 @@
/* Now try to detect function label name */
func = dev_read_string(dev, "function");
cp = dev_read_u32(dev, "color", &color);
- // prevent coverity scan error CID 541279: (TAINTED_SCALAR)
- if (color < LED_COLOR_ID_WHITE || color >= LED_COLOR_ID_MAX)
+ /*
+ * prevent coverity scan error CID 541279: (TAINTED_SCALAR)
+ * only check the upper bound. No need to check the lower bound
+ * as color is from type u32 and never can be lower than 0.
+ */
+ if (color >= LED_COLOR_ID_MAX)
cp = -EINVAL;
if (cp == 0 || func) {