Re: [PATCH v5 2/2] hwmon: scmi: Scale values to target desired HWMON units

[Sudeep Holla]

On Tue, May 14, 2019 at 09:58:06AM -0700, Guenter Roeck wrote:
> On Tue, May 14, 2019 at 09:44:02AM -0700, Florian Fainelli wrote:
> > On 5/14/19 9:37 AM, Sudeep Holla wrote:
> > > On Wed, May 08, 2019 at 11:46:35AM -0700, 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 <f.fainelli@xxxxxxxxx>
> > >> ---
> > >>  drivers/hwmon/scmi-hwmon.c | 45 ++++++++++++++++++++++++++++++++++++++
> > >>  1 file changed, 45 insertions(+)
> > >>
> > >> diff --git a/drivers/hwmon/scmi-hwmon.c b/drivers/hwmon/scmi-hwmon.c
> > >> index a80183a488c5..2c7b87edf5aa 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;
> > >> +
> > >> +	while (x--)
> > >> +		r *= 10;
> > >> +
> > >> +	return r;
> > >> +}
> > >> +
> > >> +static int 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;
> > >> +	}
> > >> +
> > >
> > > I was applying this and wanted to check if we can add a check for scale=0
> > > here and return early here to above the below check and __pow10(0) ?
> >
> > Doing an early check for scale == 0 sounds like a good idea,good catch!
> > Feel free to amend the patch directly when you apply it.
> >
>
> Ok with me. Just make it == 0 :-).
>

Thanks Guenter and Florian for quick response, done now.

--
Regards,
Sudeep