Re: [External] [PATCH 1/2] platform/x86: thinkpad_acpi: Restore X1 Carbon 9th Gen dual fan quirk

[Lyude Paul]

Some answers/comments down below

On Fri, 2022-04-29 at 21:25 -0400, Mark Pearson wrote:
> Hi Lyude
> 
> On 4/29/22 17:14, Lyude Paul wrote:
> > The new method of probing dual fan support introduced in:
> > 
> > bf779aaf56ea ("platform/x86: thinkpad_acpi: Add dual fan probe")
> > 
> > While this commit says this works on the X1 Carbon 9th Gen, it actually
> > just results in hiding the second fan on my local machine. Additionally,
> > I'm fairly sure this machine powers on quite often without either of the
> > two fans spinning.
> > 
> > So let's fix this by adding back the dual fan quirk for the X1 Carbon 9th
> > Gen.
> > 
> > Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
> > Fixes: bf779aaf56ea ("platform/x86: thinkpad_acpi: Add dual fan probe")
> > Cc: Mark Pearson <markpearson@xxxxxxxxxx>
> > Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
> > Cc: Henrique de Moraes Holschuh <hmh@xxxxxxxxxx>
> > Cc: Mark Gross <markgross@xxxxxxxxxx>
> > Cc: ibm-acpi-devel@xxxxxxxxxxxxxxxxxxxxx
> > Cc: platform-driver-x86@xxxxxxxxxxxxxxx
> > ---
> >  drivers/platform/x86/thinkpad_acpi.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/drivers/platform/x86/thinkpad_acpi.c
> > b/drivers/platform/x86/thinkpad_acpi.c
> > index c568fae56db2..9067fd0a945c 100644
> > --- a/drivers/platform/x86/thinkpad_acpi.c
> > +++ b/drivers/platform/x86/thinkpad_acpi.c
> > @@ -8699,6 +8699,7 @@ static const struct tpacpi_quirk fan_quirk_table[]
> > __initconst = {
> >         TPACPI_Q_LNV3('N', '2', 'E', TPACPI_FAN_2CTL),  /* P1 / X1 Extreme
> > (1st gen) */
> >         TPACPI_Q_LNV3('N', '2', 'O', TPACPI_FAN_2CTL),  /* P1 / X1 Extreme
> > (2nd gen) */
> >         TPACPI_Q_LNV3('N', '3', '0', TPACPI_FAN_2CTL),  /* P15 (1st gen) /
> > P15v (1st gen) */
> > +       TPACPI_Q_LNV3('N', '3', '2', TPACPI_FAN_2CTL),  /* X1 Carbon (9th
> > gen) */
> >         TPACPI_Q_LNV3('N', '3', '7', TPACPI_FAN_2CTL),  /* T15g (2nd gen)
> > */
> >         TPACPI_Q_LNV3('N', '1', 'O', TPACPI_FAN_NOFAN), /* X1 Tablet (2nd
> > gen) */
> >  };
> I just double checked this on my X1C9 - and it's working correctly. 2nd
> fan is detected correctly.
> 
> I'd rather understand why it's not working on your setup then just
> re-introduce the quirk.

Of course! I figured as much, it's just easy to start conversations with a
revert :P

> 
> What happens on your system when the
>   res = fan2_get_speed(&speed);
> is called? If that is failing it means your 2nd fan isn't responding and
> that's not supposed to happen. Could you let me know if you get an error
> code, if it happens every boot, etc
> I assume when the function is called later it works successfully?

It definitely seems to happen every boot, not sure about the error code it
returns. I will check and get you this info asap

> 
> Also please confirm which BIOS and EC version you have.

BIOS version N32ET75W (1.51) release date 12/02/2021, embedded controller is
0.1.32


> 
> Thanks
> Mark
> 

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat