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

[Guenter Roeck]

On 5/27/21 12:43 PM, Robert Marko wrote:
> On Thu, May 27, 2021 at 9:27 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> > On Thu, May 27, 2021 at 09:14:03PM +0200, Robert Marko wrote:
> > > On Thu, May 27, 2021 at 6:37 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> > > > On 5/27/21 7:58 AM, Robert Marko wrote:
> > > > [ ... ]
> > > >
> > > > > > > > > > I tried applying the block support for mv64xx as well:
> > > > > > > > > > https://patchwork.ozlabs.org/project/linux-i2c/patch/20200118115820.9080-1-fuga@xxxxxxxxxxxxxx/
> > > > > > > >
> > > > > > > > That patch would be needed, but it looks buggy to me. This chunk:
> > > > > > > >
> > > > > > > > +               drv_data->effective_length = data+1;
> > > > > > > > +               drv_data->bytes_left = data+1;
> > > > > > > > +               drv_data->msg->len = data+1;
> > > > > > > >
> > > > > > > > should be:
> > > > > > > >
> > > > > > > > +               drv_data->effective_length = data+1;
> > > > > > > > +               drv_data->bytes_left = data;
> > > > > > > > +               drv_data->msg->len = data+1;
> > > > > > > >
> > > > > > > > It should also make sure that 'data' is not larger than I2C_SMBUS_BLOCK_MAX,
> > > > > > > > and bail out if it isn't.
> > > > > > >
> > > > > > > Yeah, I did not check the contents, I just saw 2 reviews and tested it
> > > > > > > since it can't hurt.
> > > > > >
> > > > > > That patch doesn't work at all. Make the above change, and also change
> > > > > > the type of effective_length from u32 to int, and try again.
> > > > >
> > > > > I was just looking and it, and doing the changes you recommended make
> > > > > no difference at all.
> > > >
> > > > Is the i2c controller compatible with marvell,mv78230-i2c ?
> > > > The block transfers would not work in that case. Let me know
> > > > and I'll send you a patch that might fix it.
> > >
> > > Yes, the CPU is Armada 7040 and I can see that compatible is
> > > marvell,mv78230-i2c indeed.
> > >
> > > It would be great if you have the patch,
> >
> > See below.
>
> I can confirm that this does indeed enable block reads and
> i2c_smbus_read_block_data()
> works now.
>
> PMBUS_MFR_ID and PMBUS_MFR_MODEL are indeed populated.

Excellent.

Guenter