Re: [PATCH 1/2] serial: 8250: Allow port registration without UPF_BOOT_AUTOCONF

From: Esben Haabendal
Date: Mon Apr 29 2019 - 02:38:05 EST


"Enrico Weigelt, metux IT consult" <lkml@xxxxxxxxx> writes:

> On 27.04.19 10:58, Esben Haabendal wrote:
>
> Hi folks,
>
>> That said, the purpose of UPF_BOOT_AUTOCONF (for 8250 driver) is to
>> request and map the register memory. So when that is already done by
>> the parent MFD driver, I think it is silly to workaround problems
>> caused by UPF_BOOT_AUTOCONF being force setted, when it really
>> shouldn't.
> I tend to agree. Maybe we should give serial8250_register_8250_port()
> some flags for controlling this, or add another function for those
> cases.

Changing serial8250_register_8250_port() would break existing drivers,
as I have seen that some explicitly rely on the automtic addition of
UPF_BOOT_AUTOCONF.

> A minimal-invasive approach could be introducing an
> serial8250_register_8250_port_ext() with extra parameters, and let
> serial8250_register_8250_port() just call it.

So basically a rename of __serial8250_register_8250_port() in my patch
to serial8250_register_8250_port_ext()? Fine with me. Should we give
it an EXPORT_SYMBOL() also, as it is just as valid to use in modules as
the current serial8250_register_8250_port()?

/Esben