Commit fcb575bf authored by Lars Povlsen's avatar Lars Povlsen Committed by Guenter Roeck
Browse files

hwmon: (sparx5) Fix initial reading of temperature 



If the temperature is read before the internal calibration is
completed, the driver returns -EIO. Instead it should return -EAGAIN
to encourage repeating the operation.

Note (groeck): Returning -EAGAIN to userspace may result in hard loops;
some userspace code interprets -EAGAIN as request to retry immediately.
I would prefer -ENODATA, but it turns out that the thermal subsystem only
handles -EAGAIN silently, so we'll have to stick with that.

Signed-off-by: default avatarLars Povlsen <lars.povlsen@microchip.com>
Link: https://lore.kernel.org/r/20200903134704.8949-1-lars.povlsen@microchip.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent ba4f184e

drivers/hwmon/sparx5-temp.c

+1 −1
Original line number Diff line number Diff line
@@ -56,7 +56,7 @@ static int s5_read(struct device *dev, enum hwmon_sensor_types type, 
	case hwmon_temp_input:

		stat = readl_relaxed(hwmon->base + TEMP_STAT);

		if (!(stat & TEMP_STAT_VALID))

			return -EIO;

			return -EAGAIN;

		value = stat & TEMP_STAT_TEMP;

		/*

		 * From register documentation: