Re: [PATCH] hwmon: (pmbus/ibm-cffps) Do not swap max_power_out

[Brandon Wyman]

On 2021-08-30 16:27, Guenter Roeck wrote:
> On 8/30/21 2:07 PM, Brandon Wyman wrote:
> > On 2021-08-30 08:50, Eddie James wrote:
> > > On Sat, 2021-08-28 at 08:52 -0700, Guenter Roeck wrote:
> > > > On Fri, Aug 27, 2021 at 11:04:33PM +0000, Brandon Wyman wrote:
> > > > > The bytes for max_power_out from the ibm-cffps devices do not need
> > > > > to be
> > > > > swapped.
> > > > >
> > > > > Signed-off-by: Brandon Wyman <bjwyman@xxxxxxxxx>
> > > > Eddie, can you confirm this ?
> > > This can't be true for all the power supplies supported by this driver,
> > > no. I think we need to check the version first. Brandon, I tested this
> > > on witherspoon (which is psu version 1) and get 3148 watts. If it's not
> > > swapped, that would be 19468 watts...
> > >
> > > Thanks,
> > > Eddie
> > I had tested this on a variety of systems with a variety of different 
> > power supplies, but I did *NOT* test this on the Witherspoon power 
> > supplies.
> >
> > This apparently requires a bit more thought to figure out how to 
> > handle the other types and also not get Witherspoon wrong.
>
> Is the specification for those power supplies available in public ?
>
> Thanks,
> Guenter
No, unfortunately those power supply specifications are not available to 
the public.

Sorry,

Brandon

> > Thanks for checking Eddie.
> >
> > > > Thanks,
> > > > Guenter
> > > >
> > > > > ---
> > > > >   drivers/hwmon/pmbus/ibm-cffps.c | 2 +-
> > > > >   1 file changed, 1 insertion(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/drivers/hwmon/pmbus/ibm-cffps.c
> > > > > b/drivers/hwmon/pmbus/ibm-cffps.c
> > > > > index df712ce4b164..29b77f192c9e 100644
> > > > > --- a/drivers/hwmon/pmbus/ibm-cffps.c
> > > > > +++ b/drivers/hwmon/pmbus/ibm-cffps.c
> > > > > @@ -171,7 +171,7 @@ static ssize_t ibm_cffps_debugfs_read(struct
> > > > > file *file, char __user *buf,
> > > > >           cmd = CFFPS_SN_CMD;
> > > > >           break;
> > > > >       case CFFPS_DEBUGFS_MAX_POWER_OUT:
> > > > > -        rc = i2c_smbus_read_word_swapped(psu->client,
> > > > > +        rc = i2c_smbus_read_word_data(psu->client,
> > > > >                            CFFPS_MAX_POWER_OUT_CM
> > > > > D);
> > > > >           if (rc < 0)
> > > > >               return rc;
> > > > > --
> > > > > 2.25.1