From mboxrd@z Thu Jan  1 00:00:00 1970
From: u.kleine-koenig@pengutronix.de (Uwe =?iso-8859-1?Q?Kleine-K=F6nig?=)
Date: Mon, 6 Mar 2017 09:58:42 +0100
Subject: [PATCH 4/4] tty/serial: sh-sci: remove uneeded IS_ERR_OR_NULL
 calls
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To: linux-arm-kernel@lists.infradead.org
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Hello Geert,

On Mon, Mar 06, 2017 at 09:49:39AM +0100, Geert Uytterhoeven wrote:
> > Given that mctrl-gpio can be useful on legacy platforms, a device could
> > silently run without cts-gpio even there.
> 
> On platforms were CONFIG_GPIOLIB=n, this is not true, so the issue is moot.
> 
> All serial drivers using (optional) mctrl-gpio have this in Kconfig:
> 
>     select SERIAL_MCTRL_GPIO if GPIOLIB
> 
> So they will use mctrl-gpio when GPIOLIB is enabled.
> If GPIOPLIB is disabled, no flow control GPIOs are expected, and the
> driver should not break that case.

So it all boils down to the question: Is GPIOLIB=n enough to assume no
gpio is needed?

I'd say it is not.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-K?nig            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |