linux-kernel - Re: [PATCH 1/7] selftests: gpio: rework and simplify test implementation

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]

Date:   Mon, 4 Jan 2021 09:51:29 +0800
From:   Kent Gibson <warthog618@...il.com>
To:     Andy Shevchenko <andy.shevchenko@...il.com>
Cc:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@...r.kernel.org>,
        "open list:KERNEL SELFTEST FRAMEWORK" 
        <linux-kselftest@...r.kernel.org>,
        Bartosz Golaszewski <bgolaszewski@...libre.com>,
        Linus Walleij <linus.walleij@...aro.org>,
        Shuah Khan <shuah@...nel.org>,
        Bamvor Jian Zhang <bamv2005@...il.com>
Subject: Re: [PATCH 1/7] selftests: gpio: rework and simplify test
 implementation

On Sun, Jan 03, 2021 at 05:10:10PM +0200, Andy Shevchenko wrote:
> On Sun, Jan 3, 2021 at 4:17 AM Kent Gibson <warthog618@...il.com> wrote:
> > On Sun, Jan 03, 2021 at 12:20:26AM +0200, Andy Shevchenko wrote:
> > > On Sat, Jan 2, 2021 at 4:32 AM Kent Gibson <warthog618@...il.com> wrote:
> 
[snip]
> 
> ...
> 
> > > > +       local platform=`cat $SYSFS/kernel/debug/gpio | grep "$chip:" | tr -d ',' | awk '{print $5}'`
> > >
> > > Besides useless use of cat (and tr + awk can be simplified) why are
> >
> > What do you suggest for the tr/awk simplification?
> 
> You have `awk`, you can easily switch the entire pipeline to a little
> awk scriptlet.
> 

Baah, the number that I'm after is in the $SYSFS/kernel/debug/gpio that I
was pulling the platform from, so I can just pull it directly from there.

No need to go hunting through the file system for the base file - the
range of GPIOs assigned to the chip is right there.

In this example it is the 508:

# e.g. gpiochip0: GPIOs 508-511, parent: platform/gpio-mockup.0, gpio-mockup-A:

So I'll use that - unless it is unreliable for some reason?

Cheers,
Kent.