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Date:   Tue, 30 May 2023 11:48:14 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Niklas Schnelle <schnelle@linux.ibm.com>
Cc:     Arnd Bergmann <arnd@arndb.de>, Jiri Slaby <jirislaby@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= 
        <u.kleine-koenig@pengutronix.de>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Alan Stern <stern@rowland.harvard.edu>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        linux-pci@vger.kernel.org, Arnd Bergmann <arnd@kernel.org>,
        linux-serial@vger.kernel.org
Subject: Re: [PATCH v4 33/41] tty: serial: handle HAS_IOPORT dependencies
Message-ID: <2023053059-self-mangle-30b6@gregkh>
References: <20230516110038.2413224-1-schnelle@linux.ibm.com>
 <20230516110038.2413224-34-schnelle@linux.ibm.com>
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On Tue, May 16, 2023 at 01:00:29PM +0200, Niklas Schnelle wrote:
> In a future patch HAS_IOPORT=n will result in inb()/outb() and friends
> not being declared. We thus need to add HAS_IOPORT as dependency for
> those drivers using them unconditionally. For 8250 based drivers some
> support MMIO only use so fence only the parts requiring I/O ports.

Why can't you have dummy inb()/outb() so we don't need these #ifdefs all
over the place in .c files?  Was that documented somewhere?  We do that
for other driver/hardware apis, why are these so special they don't
deserve that?

Otherwise this makes old drivers really messy with these additional
#ifdefs, something we never wanted to do in .c files.

thanks,

greg k-h