Re: [RFC PATCH] gpio: add GPIO hogging mechanism

From: boris brezillon
Date: Thu Dec 19 2013 - 12:30:10 EST


Hello Felipe,

On 19/12/2013 17:47, Felipe Balbi wrote:
On Thu, Dec 19, 2013 at 08:41:09AM -0800, Greg Kroah-Hartman wrote:
On Thu, Dec 19, 2013 at 03:34:31PM +0100, Boris BREZILLON wrote:
GPIO hogging is a way to request and configure specific GPIO without
explicitly requesting it in the device driver.

The request and configuration procedure is handled in the core device
driver code before the driver probe function is called.

It allows specific GPIOs to be configured without any driver specific code.

Particularly usefull when a external device is connected to a bus and the
bus connections depends on an external switch controlled by a GPIO pin.
for external switches, you probably need a pinctrl-gpio driver.

Do you mean using pinctrl pinconf to configure the PIN as output-high or
output-low ?

This was my first proposal
(see https://www.mail-archive.com/devicetree@xxxxxxxxxxxxxxx/msg05829.html).


Best Regards,

Boris
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