[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <548F7809.1020303@broadcom.com>
Date: Mon, 15 Dec 2014 16:08:41 -0800
From: Ray Jui <rjui@...adcom.com>
To: Arnd Bergmann <arnd@...db.de>,
<linux-arm-kernel@...ts.infradead.org>
CC: Alexandre Courbot <gnurou@...il.com>,
Mark Rutland <mark.rutland@....com>,
"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
Florian Fainelli <f.fainelli@...il.com>,
Russell King <linux@....linux.org.uk>,
Scott Branden <sbranden@...adcom.com>,
Pawel Moll <pawel.moll@....com>,
Ian Campbell <ijc+devicetree@...lion.org.uk>,
Linus Walleij <linus.walleij@...aro.org>,
Christian Daudt <bcm@...thebug.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
Matt Porter <mporter@...aro.org>,
Joe Perches <joe@...ches.com>,
Rob Herring <robh+dt@...nel.org>,
<bcm-kernel-feedback-list@...adcom.com>,
"linux-gpio@...r.kernel.org" <linux-gpio@...r.kernel.org>,
Kumar Gala <galak@...eaurora.org>,
Grant Likely <grant.likely@...aro.org>
Subject: Re: [PATCH v5 1/3] gpio: Cygnus: define Broadcom Cygnus GPIO binding
On 12/15/2014 1:57 PM, Arnd Bergmann wrote:
> On Monday 15 December 2014 13:35:47 Ray Jui wrote:
>>
>> Like I said previously, dynamic GPIO allocation works fine in the
>> kernel, as long as all of our GPIO clients in the kernel use gpiod based
>> API, which is what we will enforce going forward. The only problem is
>> with some of our customers who use GPIO through sysfs and expect fixed
>> global GPIO numbers. Thinking about this more, it's probably not that
>> difficult to add a script for those customers to convert/map the GPIO
>> numbers based on readings parsed from sysfs, so I guess that's fine.
>>
>
> I think we discussed the user space interface a number of times
> in the past, but I forgot the outcome. Either there is already
> a way to name gpio lines uniquely in sysfs, or there should be
> one.
>
> Can you reach the gpio interfaces using /sys/devices/0001234.bus/1234566.gpiocontroller/...?
>
> Arnd
>
We use entries under /sys/class/gpio/ to control GPIOs. All base, label,
and ngpio info specific to a GPIO controller can be found there.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists