Re: [RFC PATCH v2 4/4] hwmon: (jc42) Don't cache the temperature register

From: Martin Blumenstingl
Date: Thu Oct 20 2022 - 18:22:29 EST


Hi Guenter,

On Fri, Oct 21, 2022 at 12:14 AM Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
>
> On Thu, Oct 20, 2022 at 11:03:20PM +0200, Martin Blumenstingl wrote:
> > Now that we're utilizing regmap and it's regcache for the
> > minimum/maximum/critical temperature registers the only cached register
> > that's left is the actual temperature register. Drop the custom cache
> > implementation as it just complicates things.
> >
>
> Ah, you got there eventually. Just combine this patch into the first
> patch of the series. No need to keep separate patches, especially since
> a lot of the code changed in patch 1 and 2 is just thrown away here.
Thanks again for the quick response and for the great feedback. I'll
combine the patches tomorrow and send a v3!

> That reminds me, though: Make sure that the alarm bits are not dropped
> after reading the temperature (running the 'sensors' command with
> alarms active should do). I have some JC42 chips here and will do the
> same.
I configured below ambient high and crit temperatures:
jc42-i2c-0-1a
Adapter: SMBus PIIX4 adapter port 0 at 0b00
temp1: +35.0°C (low = +0.0°C) ALARM (HIGH, CRIT)
(high = +25.0°C, hyst = +25.0°C)
(crit = +30.0°C, hyst = +30.0°C)

Then I ran "sensors" three times in a row.
The output of all "sensors" commands is the same, meaning all of them
show the ALARM (HIGH, CRIT) part.

Do you want me to mention this somewhere (for example in the
cover-letter or the new patch #1)?


Best regards,
Martin