RE: [PATCH v5 2/4] hwmon: max31827: Add support for max31828 and max31829

From: Matyas, Daniel
Date: Fri Oct 27 2023 - 11:05:58 EST




> -----Original Message-----
> From: Guenter Roeck <groeck7@xxxxxxxxx> On Behalf Of Guenter Roeck
> Sent: Friday, October 27, 2023 5:52 PM
> To: Matyas, Daniel <Daniel.Matyas@xxxxxxxxxx>
> Cc: Jean Delvare <jdelvare@xxxxxxxx>; Jonathan Corbet
> <corbet@xxxxxxx>; linux-hwmon@xxxxxxxxxxxxxxx; linux-
> doc@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v5 2/4] hwmon: max31827: Add support for
> max31828 and max31829
>
> [External]
>
> On 10/27/23 06:00, Matyas, Daniel wrote:
> [ ... ]
>
> >> I also don't understand why that would be chip specific. I don't see
> >> anything along that line in the datasheet.
> >>
> >> Ah, wait ... I guess that is supposed to reflect the chip default.
> >> I don't see why the chip default makes a difference - a well defined
> >> default must be set either way. Again, there is no guarantee that the
> >> chip is in its default state when the driver is loaded.
> >
> > The well defined default was set in v4, but I deleted it, because the
> default value in hex for max31827 and max31828 alarm polarity, and
> max31827 fault queue is 0x0. I had 2 #defines for these values, but you
> said:
> > " Since MAX31827_ALRM_POL_LOW is 0, this code doesn't really do
> anything and just pollutes the code."
> >
> > So, I thought I should remove it altogether, since res is set to 0 in the
> beginning and the default value of these chips (i.e. 0) is implicitly set.
> >
> >>
> >> Also, why are the default values added in this patch and not in the
> >> previous patch ?
> >>
> >
> > In v4 these default values were set in the previous patch.
> >
>
> I asked you (or meant to ask you) to stop overwriting 0 with 0 in a
> variable. I didn't mean to ask you (if I did) to stop writing the default value
> into the chip. Sorry if I did; if so, that was a misunderstanding.
>
> Guenter

Well, writing the default value into res, would just overwrite 0 with 0. Should I still do it?

Daniel