On 5/7/19 4:09 PM, Florian Fainelli wrote:
If the SCMI firmware implementation is reporting values in a scale that
is different from the HWMON units, we need to scale up or down the value
according to how far appart they are.
Signed-off-by: Florian Fainelli <[email protected]>
---
drivers/hwmon/scmi-hwmon.c | 43 +++++++++++++++++++++++++++++++++++++-
1 file changed, 42 insertions(+), 1 deletion(-)
diff --git a/drivers/hwmon/scmi-hwmon.c b/drivers/hwmon/scmi-hwmon.c
index a80183a488c5..7820854e5954 100644
--- a/drivers/hwmon/scmi-hwmon.c
+++ b/drivers/hwmon/scmi-hwmon.c
@@ -18,6 +18,47 @@ struct scmi_sensors {
const struct scmi_sensor_info **info[hwmon_max];
};
+static inline u64 __pow10(u8 x)
+{
+ u64 r = 1;
+
+ if (unlikely(x > 18))
+ return r;
+
Strictly speaking that would be 19 (10^19=0x8AC7230489E80000),
and I am not sure if returning 1 in that case is such a good idea.
If you really want to handle over/underflow situations, it should
be in the calling code.
Thanks,
Guenter
+ while (x--)
+ r *= 10;
+
+ return r;
+}
+
+static u64 scmi_hwmon_scale(const struct scmi_sensor_info *sensor, u64 value)
+{
+ s8 scale = sensor->scale;
+ u64 f;
+
+ switch (sensor->type) {
+ case TEMPERATURE_C:
+ case VOLTAGE:
+ case CURRENT:
+ scale += 3;
+ break;
+ case POWER:
+ case ENERGY:
+ scale += 6;
+ break;
+ default:
+ break;
+ }
+
+ f = __pow10(abs(scale));
+ if (scale > 0)
+ value *= f;
+ else
+ value = div64_u64(value, f);
+
+ return value;
+}
+
static int scmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *val)
{
@@ -30,7 +71,7 @@ static int scmi_hwmon_read(struct device *dev, enum
hwmon_sensor_types type,
sensor = *(scmi_sensors->info[type] + channel);
ret = h->sensor_ops->reading_get(h, sensor->id, false, &value);
if (!ret)
- *val = value;
+ *val = scmi_hwmon_scale(sensor, value);
return ret;
}
