> -----Original Message-----
> From: Guenter Roeck <groeck7@xxxxxxxxx> On Behalf Of Guenter Roeck
> Sent: Monday, February 24, 2020 4:27 PM
> To: Vadim Pasternak <vadimp@xxxxxxxxxxxx>
> Cc: linux-hwmon@xxxxxxxxxxxxxxx
> Subject: Re: [hwmon-next v1 2/2] hwmon: (pmbus/xdpe12284) Add custom
> format for vout limits conversion
>
> On 2/24/20 5:12 AM, Vadim Pasternak wrote:
> > Provide callback for overvoltage and undervoltage output readouts
> > conversion. These registers are presented in 'slinear11' format, while
> > default conversion for 'vout' class for the devices is 'vid'. It is
> > resulted in wrong conversion in pmbus_reg2data() for in{3-4}_lcrit and
> > in{3-4}_crit attributes.
> >
> > Signed-off-by: Vadim Pasternak <vadimp@xxxxxxxxxxxx>
> > ---
> > drivers/hwmon/pmbus/xdpe12284.c | 23 +++++++++++++++++++++++
> > 1 file changed, 23 insertions(+)
> >
> > diff --git a/drivers/hwmon/pmbus/xdpe12284.c
> > b/drivers/hwmon/pmbus/xdpe12284.c index ecd9b65627ec..751c8e18c881
> > 100644
> > --- a/drivers/hwmon/pmbus/xdpe12284.c
> > +++ b/drivers/hwmon/pmbus/xdpe12284.c
> > @@ -18,6 +18,28 @@
> > #define XDPE122_AMD_625MV 0x10 /* AMD mode 6.25mV */
> > #define XDPE122_PAGE_NUM 2
> >
> > +static int xdpe122_reg2data(u16 reg, int data, long *val) {
> > + s16 exponent;
> > + s32 mantissa;
> > +
> > + switch (reg) {
> > + case PMBUS_VOUT_OV_FAULT_LIMIT:
> > + case PMBUS_VOUT_UV_FAULT_LIMIT:
>
> Another situation where having a datasheet would be quite valuable.
>
> I would suggest to implement reading those two registers locally and convert
> them to the expected data format. That seems to be more straightforward than
> re-implementing slinear conversion.
Hi Guenter,
Do you mean to implement them locally through the virtual registers?
case PMBUS_VIRT_VMON_OV_FAULT_LIMIT:
case PMBUS_VIRT_VMON_UV_FAULT_LIMIT:
Thanks,
Vadim.
>
> Thanks,
> Guenter
>
> > + /* Convert to LINEAR11. */
> > + exponent = ((s16)data) >> 11;
> > + mantissa = ((s16)((data & GENMASK(10, 0)) << 5)) >> 5;
> > + *val = mantissa * 1000L;
> > + if (exponent >= 0)
> > + *val <<= exponent;
> > + else
> > + *val >>= -exponent;
> > + return 0;
> > + default:
> > + return -ENODATA;
> > + }
> > +}
> > +
> > static int xdpe122_identify(struct i2c_client *client,
> > struct pmbus_driver_info *info)
> > {
> > @@ -70,6 +92,7 @@ static struct pmbus_driver_info xdpe122_info = {
> > PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
> > PMBUS_HAVE_POUT | PMBUS_HAVE_PIN |
> PMBUS_HAVE_STATUS_INPUT,
> > .identify = xdpe122_identify,
> > + .reg2data = xdpe122_reg2data,
> > };
> >
> > static int xdpe122_probe(struct i2c_client *client,
> >
