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Date: Fri, 3 May 2024 18:32:10 +0300
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Sunil V L <sunilvl@ventanamicro.com>
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Subject: Re: [PATCH v5 17/17] serial: 8250: Add 8250_acpi driver
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Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo

On Fri, May 03, 2024 at 07:29:35PM +0530, Sunil V L wrote:
> On Thu, May 02, 2024 at 06:35:52PM +0300, Andy Shevchenko wrote:
> > On Thu, May 02, 2024 at 04:50:57PM +0530, Sunil V L wrote:
> > > On Thu, May 02, 2024 at 01:09:57PM +0300, Andy Shevchenko wrote:
> > > > On Thu, May 02, 2024 at 03:20:08PM +0530, Sunil V L wrote:
> > > > > On Thu, May 02, 2024 at 12:17:59PM +0300, Andy Shevchenko wrote:

..

> > > > > This driver is not a duplicate of 8250_pnp. It just relies on UART
> > > > > enumerated as platform device instead of using PNP interfaces.
> > > > > Isn't it better and simple to have an option to enumerate as platform
> > > > > device instead of PNP? 
> > > > 
> > > > Ah, then extract platform driver first from 8250_core.c.
> > > > 
> > > Let me know if I understand your suggestion correctly. Do you mean call
> > > something like serial8250_acpi_init() from serial8250_init() and
> > > register the driver directly in serial8250_acpi_init()?
> > 
> > Extract the code to be 8250_platform.c and update that file.
> > I have locally the extraction of RSA code, I will see if I can help you
> > with the rest.
> > 
> Thanks!. That will be helpful. TBH, I don't understand what to do for
> extracting the platform driver code. There are already several vendor
> specific UART drivers (ex: 8250_fsl.c) which are enumerated as platform
> devices. 8250_core.c looks cleanly supporting such drivers which can
> register themselves with the core. For generic UART, DT has 8250_of.c
> and ACPI has 8250_pnp.c. But 8250_pnp.c comes with baggage of PNP
> contract. So, the driver in this patch is similar to vendor specific
> drivers to support generic uart devices which are enumerated as platform
> device.

> I can rename 8250_acpi.c to 8250_platform.c if that is better.

No, that's not what I meant. We _already_ have a generic platform driver,
it's just inline in the 8250_core.c and needs to be extracted. When it's done,
you may simply add an ACPI table to it.

> Could you please help with a patch even if not compiled so that I can
> understand your suggestion better? 

-- 
With Best Regards,
Andy Shevchenko