[PATCH] hwmon: (ads7871) Fix incorrect error code in voltage_show

[Tabrez Ahmed <tabreztalks@gmail.com>]

The voltage_show() function returns -1 when the A/D conversion
fails to complete within the polling loop. -1 maps to -EPERM
(operation not permitted), which does not describe the actual
failure.

Replace this -1 error code with -ETIMEDOUT to better indicate
the timeout condition to userspace.

Note: not runtime tested due to lack of hardware.

Signed-off-by: Tabrez Ahmed <tabreztalks@gmail.com>
---
Note: This patch applies on top of my previously submitted patch:
"hwmon: (ads7871) Replace sprintf() with sysfs_emit()"
 
 drivers/hwmon/ads7871.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/ads7871.c b/drivers/hwmon/ads7871.c
index b84426c940c5e..4df54c86f786c 100644
--- a/drivers/hwmon/ads7871.c
+++ b/drivers/hwmon/ads7871.c
@@ -126,7 +126,7 @@ static ssize_t voltage_show(struct device *dev, struct device_attribute *da,
 		val = ((val >> 2) * 25000) / 8192;
 		return sysfs_emit(buf, "%d\n", val);
 	} else {
-		return -1;
+		return -ETIMEDOUT;
 	}
 }
 
-- 
2.43.0