Re: [PATCH 18/18] ipu3: Add driver for dummy INT3472 ACPI device

From: Andy Shevchenko
Date: Wed Dec 02 2020 - 04:40:42 EST


On Tue, Dec 01, 2020 at 08:59:53PM +0000, Dan Scally wrote:
> On 01/12/2020 18:49, Andy Shevchenko wrote:

...

> > Seems we can do this, by locating intel_int3472.c under PDx86 hood and dropping
> > ACPI ID table from TPS68470 MFD driver. The PMIC can be instantiated via
> > i2c_acpi_new_device() (IIRC the API name).
> >
> > And actually it makes more sense since it's not and MFD and should not be there.
> >
> > (Dan, patch wise the one creates intel_int3472.c followed by another one that
> > moves ACPI ID from PMIC and introduces its instantiation via I²C board info
> > structure)
>
> I'm mostly following this, but why would we need an i2c_board_info or
> i2c_acpi_new_device()? The INT3472 entries that refer to actual tps68470
> devices do have an I2cSerialBusV2 enumerated in _CRS so in their case
> there's an i2c device registered with the kernel already.

Because as we discussed already we can't have two drivers for the same ID
without a big disruption in the driver(s).

If you have a single point of enumeration, it will make things much easier
(refer to the same intel_cht_int33fe driver you mentioned earlier).

I just realize that the name of int3472 should follow the same pattern, i.e.
intel_skl_int3472.c

> I think we need those things when we get round to handling the
> VCM/EEPROM that's hidden within the sensor's ACPI entry, but I've not
> done any work on that yet at all.

Let's consider this later — one step at a time.

--
With Best Regards,
Andy Shevchenko