drivers: w1: fix return check in bit_read for w1-gpio

The driver masked the return value of a pin read operation before checking the error. Thus not detecting a potential error and leading to logically dead code, which was detected by coverity in CID 340853. Anther instance XORs 1 before returning, resulting in an unexpected return value; Signed-off-by: Thomas Stranger <[email protected]>
zephyrproject-rtos · Feb 8, 2024 · 505cc19 · 505cc19
1 parent 199487b
commit 505cc19
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/drivers/w1/w1_zephyr_gpio.c b/drivers/w1/w1_zephyr_gpio.c
@@ -156,10 +156,11 @@ static int w1_gpio_reset_bus(const struct device *dev)
 	}
 
 	W1_GPIO_WAIT_US(timing->i);
-	ret = gpio_pin_get_dt(spec) ^ 0x01;
+	ret = gpio_pin_get_dt(spec);
 	if (ret < 0) {
 		goto out;
 	}
+	ret ^= 0x01;
 
 	W1_GPIO_WAIT_US(timing->j);
 out:
@@ -190,10 +191,11 @@ static int w1_gpio_read_bit(const struct device *dev)
 	}
 
 	W1_GPIO_WAIT_US(timing->e);
-	ret = gpio_pin_get_dt(spec) & 0x01;
+	ret = gpio_pin_get_dt(spec);
 	if (ret < 0) {
 		goto out;
 	}
+	ret &= 0x01;
 
 	W1_GPIO_WAIT_US(timing->f);
 out: