From mboxrd@z Thu Jan  1 00:00:00 1970
From: Lee Jones <lee.jones@linaro.org>
Subject: Re: [PATCH] serial: 8250: Add support for using platform_device
 resources
Date: Tue, 7 May 2019 10:36:31 +0100
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To: Esben Haabendal <esben@haabendal.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>, linux-serial@vger.kernel.org, Enrico Weigelt <lkml@metux.net>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Jiri Slaby <jslaby@suse.com>, Darwin Dingel <darwin.dingel@alliedtelesis.co.nz>, Jisheng Zhang <Jisheng.Zhang@synaptics.com>, Sebastian Andrzej Siewior <bigeasy@linutronix.de>, He Zhe <zhe.he@windriver.com>, Marek Vasut <marex@denx.de>, Douglas Anderson <dianders@chromium.org>, Paul Burton <paul.burton@mips.com>, linux-kernel@vger.kernel.org
List-Id: linux-serial@vger.kernel.org

On Tue, 07 May 2019, Lee Jones wrote:

> On Thu, 02 May 2019, Esben Haabendal wrote:
> 
> > Hi Lee
> > 
> > Could you help clarify whether or not this patch is trying to do
> > something odd/wrong?
> > 
> > I might be misunderstanding Andy (probably is), but the discussion
> > revolves around the changes I propose where I change the serial8250
> > driver to use platform_get_resource() in favour of
> > request_mem_region()/release_mem_region().
> 
> Since 'serial8250' is registered as a platform device, I don't see any
> reason why it shouldn't have the capability to obtain its memory
> regions from the platform_get_*() helpers.

Not sure which device you're trying to enable, but if it's booted
using Device Tree, you could always use 'of_serial'.

It does seem a little odd that the 'serial8250' IP block has been
incorporated into an MFD.  Which device is it you're trying to enable
exactly? 

> > In my understanding, use of platform_get_resource() is the right thing
> > to do in order to integrate properly with with MFD drivers that splits a
> > common memory resource in mfd_add_device() using the mem_base argument.
> 

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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