Re: [PATCHv3 0/3] OMAP UART: Adding support for omap-serial driver.

From: Olof Johansson <olof@lixom.net>
To: "G, Manjunath Kondaiah" <manjugk@ti.com>
Cc: "Shilimkar, Santosh" <santosh.shilimkar@ti.com>,
	Govindraj <govindraj.ti@gmail.com>,
	Tony Lindgren <tony@atomide.com>,
	"linux-omap@vger.kernel.org" <linux-omap@vger.kernel.org>,
	"Pandita, Vikram" <vikram.pandita@ti.com>,
	"Raja, Govindraj" <govindraj.raja@ti.com>
Subject: Re: [PATCHv3 0/3] OMAP UART: Adding support for omap-serial driver.
Date: Wed, 25 Nov 2009 01:06:10 -0600	[thread overview]
Message-ID: <4B0CD762.70707@lixom.net> (raw)
In-Reply-To: <E0D41E29EB0DAC4E9F3FF173962E9E9402543D7ED2@dbde02.ent.ti.com>

G, Manjunath Kondaiah wrote:
>>> You should allow both of them to be enabled at the same time, so the
>>> same
>>> kernel can for example be booted on a ZOOM2 with debug board
>>> attached
>>> (8250 on GPMC), or on a beagle/overo board.
>>>
>>> Making them exclusive would be a step backwards.
>>>       
>> More so, selecting both config option really shouldn't break 
>> the build. If one expect a build break because only one of 
>> the options can be enabled then clearly the dependency should 
>> be used so that user can select only one option at a time.
>>     
>
> Ack. There should be dependency in Kconfig so that user can select
> either 8250 console(through Quad-uart for zoom2/zoom3) or OMAP-serial
> Console(through OMAP UART's).
>   

No. The drivers MUST handle co-existing. You can have a bunch of drivers 
configured to be _potential_ consoles, which one will end up being used 
depends on, among other things, the bootargs. But it should be allowed 
to configure both 8250 and omap-serial at the same time.

-Olof