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Date: Thu, 2 May 2024 13:09:57 +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
Message-ID: <ZjNmdfR2J6hNnYle@smile.fi.intel.com>
References: <20240501121742.1215792-1-sunilvl@ventanamicro.com>
 <20240501121742.1215792-18-sunilvl@ventanamicro.com>
 <ZjNaR-YtVTm4pbP7@smile.fi.intel.com>
 <ZjNh0Llcx+0VHevy@sunil-laptop>
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Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo

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:
> > On Wed, May 01, 2024 at 05:47:42PM +0530, Sunil V L wrote:

..

> > > + * This driver is for generic 16550 compatible UART enumerated via ACPI
> > > + * platform bus instead of PNP bus like PNP0501. This is not a full
> > 
> > This has to be told in the commit message. Anyway, we don't need a duplication
> > code, please use 8250_pnp.
> 
> Thank you for the review!. Major issue with PNP0501 is, it gets enumerated
> in a different way which causes issue to get _DEP to work.
> pnpacpi_init() creates PNP data structures which gets skipped if the
> UART puts _DEP on the GSI provider (interrupt controller). In that case,
> we need to somehow reinitialize such PNP devices after interrupt
> controller gets probed.

Then fix that code, we don't want a hack driver on top of the existing one for
the same.

What I might think out of head is that used IRQ core for your case should
return a deferred probe error code when it's not ready, then 8250_pnp will
get reprobed.

> I tried a solution [1] but it required several
> functions to be moved out of __init. 

> 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.

> [1] - https://patchwork.kernel.org/project/linux-pci/patch/20240415170113.662318-14-sunilvl@ventanamicro.com/

-- 
With Best Regards,
Andy Shevchenko