Re: [PATCH 1/3] hwmon: (pmbus) Add driver for Delta DPS-920AB PSU

[Guenter Roeck]

On 5/21/21 5:33 AM, Robert Marko wrote:
> On Fri, May 21, 2021 at 1:41 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> > On 5/21/21 1:36 AM, Robert Marko wrote:
> > [ ... ]
> > > > In this context, I have a hard time finding a reference for
> > > > this power supply. Do you have a datasheet or some other documents
> > > > you can share ?
> > >
> > > Unfortunately, I don't have a datasheet as that would have made this way easier.
> > > It was all based on the vendor "driver" from DENT:
> > > https://github.com/dentproject/dentOS/blob/main/packages/platforms/delta/arm64/tn48m/tn48m-poe/modules/builds/src/arm64-delta-tn48m-poe-psu.c
> >
> > Ah, so this is not a driver for a power supply from DeltaPSU,
> > but a power supply from Delta Networks Technology Corporation,
> > as used in that company's TN48M-POE switch. That is a world
> > of difference, even though the parent company seems to be the
> > same. I am not sure if, based on this information, the driver
> > should claim to be for "Delta DPS-920AB PSU" in the first place.
>
> It's actually a PSU from Delta Electronics INC, Delta Networks are just using
> it inside of the Delta Networks TN48M-DN-P switch.
> I checked the label on the PSU-s.

Ok, thanks. Guess we'll have to live with that.

> > Can you run a block read on MFR_MODEL and MFG_SERIAL ?
> > That might give us an idea about the actual manufacturer
> > and model of this power supply.
>
> MFG_SERIAL is just a bunch of 0xf-s, but MFR_MODEL has something.
> However, the Armada 7040 I2C adapter cannot do block reads although
> it returns 11 bytes but it's just zeros.

Hmm, it seems more likely that the field is empty. Block read
isn't really different from other read operations.

Thanks,
Guenter

> > Also, isn't that the same power supply for which you were
> > trying to add another hwmon driver to display some of its
> > status information, obtained from some CPLD ?
>
> This and one more as the non-PoE version of the TN48M-DN switch
> has a single 150W PSU that does not support PMBus, but the CPLD
> always provides presence information and Power Good status.
> > Thanks,
> > Guenter