Re: [PATCH v3 09/11] serial: 8250_lpss: move Quark code from PCI driver

From: Andy Shevchenko
Date: Wed May 04 2016 - 06:03:43 EST


On Wed, May 4, 2016 at 12:51 PM, Bryan O'Donoghue
<pure.logic@xxxxxxxxxxxxxxxxx> wrote:
> On Wed, 2016-05-04 at 12:42 +0300, Andy Shevchenko wrote:
>> On Wed, May 4, 2016 at 12:31 PM, Bryan O'Donoghue
>> <pure.logic@xxxxxxxxxxxxxxxxx> wrote:
>> > Andy,
>> >
>> > If you are going to start removing working PCI devices from the PCI
>> > config table in favour of a shim in SERIAL_8250_LPSS then the very
>> > minimum should be some sort of dependency link between
>> > SERIAL_8250_LPSS
>> > and CONFIG_SERIAL_8250_PCI in kconfig.
>> >
>> > A user could reasonably read the QRK datasheet - switch on
>> > CONFIG_SERIAL_8250_PCI and then wonder why no console output
>> > happened
>> > on boot. S/he shouldn't have to know that devices were moved from
>> > the
>> > PCI driver to an LPSS shim driver or that the 8250_lpss driver now
>> > needs to be selected instead of the intuitively correct 8250_pci
>> > driver.
>>
>> That is taken care of since default is set to SERIAL_8250 (you even
>> don't need to have PCI driver enabled!).
>> Doesn't work for you?
>
> The default may be set to SERIAL_8250 but, without the QRK specific
> entry in 8250_pci.c you won't get console output.
>
> So if you are going to remove the QRK entry from 8250_pci.c and stuff
> it into 8250_lpss.c then 8250_lpss needs to be selected by
> CONFIG_SERIAL_8250_PCI.

Why?!

Now it should be enough to have SERIAL_8250 set to non-n to have
8250_lpss compiled.
Can you check it?

>
> Otherwise the person doing the config needs to know that stuff was
> moved from one file to another - even though it's a PCI device (not an
> LPSS/ACPI enumerated device) - which seems like an unreasonable level
> of knowledge to assume on the part of the user.
>

I understand that, that's why Heikki proposed to do something sane for
8250_mid and I use it as an example for this one.

--
With Best Regards,
Andy Shevchenko