linux-kernel - Re: [PATCH] serial: 8250: Add support for using platform

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20190507093631.GC4529@dell>
Date:   Tue, 7 May 2019 10:36:31 +0100
From:   Lee Jones <lee.jones@...aro.org>
To:     Esben Haabendal <esben@...bendal.dk>
Cc:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        linux-serial@...r.kernel.org, Enrico Weigelt <lkml@...ux.net>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Jiri Slaby <jslaby@...e.com>,
        Darwin Dingel <darwin.dingel@...iedtelesis.co.nz>,
        Jisheng Zhang <Jisheng.Zhang@...aptics.com>,
        Sebastian Andrzej Siewior <bigeasy@...utronix.de>,
        He Zhe <zhe.he@...driver.com>, Marek Vasut <marex@...x.de>,
        Douglas Anderson <dianders@...omium.org>,
        Paul Burton <paul.burton@...s.com>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] serial: 8250: Add support for using platform_device
 resources

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
Follow Linaro: Facebook | Twitter | Blog