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Subject: Re: [PATCH 0/3] 8250: Split Fintek PCIE to UART to independent file
To: Sudip Mukherjee <sudipm.mukherjee@gmail.com>, Rob Groner <rgroner@rtd.com>
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From: Peter Hung <hpeter@gmail.com>
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Date: Wed, 20 Jan 2016 16:24:36 +0800
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Hi Sudip,

Sudip Mukherjee 於 2016/1/20 下午 02:22 寫道:
> On Wed, Jan 20, 2016 at 10:59:28AM +0800, Peter Hung wrote:

> But my personal opinion, if we move out the serial port related code
> into a new driver (a new Kconfig symbol) userspace of many system will
> break if this new symbol is not enabled by the distributions. But in the
> way I have done the new symbol needs to be enabled only if the user
> wants to use the GPIO capability. If that is not enabled GPIO cannot be
> used but it will never break the serial port related code for them.
> I think we should give a thought to that before splitting out the codes
> from 8250_pci.

I agree with your opinion. I'm trying to implement GPIO with 2 ways,
One is like yours, add platform_device with in 8250_pci.c and implement
GPIOLIB platform driver with in 'driver/gpio", and the other is trying
split out from 8250_pci.c to MFD.

In my personal opinion, the first method is less impact with compatible
old system.
-- 
With Best Regards,
Peter Hung