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Date: Mon, 7 Jul 2014 18:23:09 +0300
From: Baruch Siach <baruch@tkos.co.il>
To: Linus Walleij <linus.walleij@linaro.org>
Cc: =?iso-8859-1?Q?S=F6ren?= Brinkmann <soren.brinkmann@xilinx.com>,
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Subject: Re: [PATCH v2 1/2] gpio: Add driver for Zynq GPIO controller
Message-ID: <20140707152309.GH4939@tarshish>
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Hi Linux,

On Mon, Jul 07, 2014 at 04:51:56PM +0200, Linus Walleij wrote:
> On Wed, Jun 18, 2014 at 5:36 PM, Sören Brinkmann <soren.brinkmann@xilinx.com> wrote:
> > The first is, how is userspace supposed to find the correct offset for a
> > GPIO pin.
> 
> The sysfs interface to GPIO is *NOT* *GOOD* this is universally
> agreed upon.
> 
> This needs someone to step in and provide a replacement, my preferred
> mechanism would be a /dev/gpiochip0/... hierarchy using char devices.

I really like the ability to control GPIOs from shell, both interactively and 
scripted. I find it useful for quick hardware level debugging, and for boot 
time scripting (mainly in initramfs). Do you intend to preserve this 
capability in the future? Will I need a special utility (or Busybox applet) to 
do this with char device ioctl?

baruch

-- 
     http://baruch.siach.name/blog/                  ~. .~   Tk Open Systems
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