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

[Dan Scally]

On 02/12/2020 09:39, Andy Shevchenko wrote:
> 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

Ah! I didn't read intel_cht_int33fe_common.c before, just the typec.c.
Having reviewed common I think I'm clear on the method now, thank you :)


>> 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.

Agree!