From mboxrd@z Thu Jan  1 00:00:00 1970
From: robh@kernel.org (Rob Herring)
Date: Thu, 17 Mar 2016 15:00:54 -0500
Subject: [PATCH 14/18] gpio: vf610: add support for WKPU unit
In-Reply-To: <1457576219-7971-15-git-send-email-stefan@agner.ch>
References: <1457576219-7971-1-git-send-email-stefan@agner.ch>
 <1457576219-7971-15-git-send-email-stefan@agner.ch>
Message-ID: <20160317200054.GA3799@rob-hp-laptop>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Wed, Mar 09, 2016 at 06:16:55PM -0800, Stefan Agner wrote:
> WKPU unit support within the VF610 GPIO driver. The WKPU unit allows
> some GPIO to be the wakeup source from lowest power modes LPSTOPx.
> The relationship between the GPIO banks and the WKPU GPIO numbering
> can be derived from the device tree property fsl,gpio-wakeup.
> 
> Signed-off-by: Stefan Agner <stefan@agner.ch>
> ---
>  .../devicetree/bindings/gpio/gpio-vf610.txt        |   6 +
>  drivers/gpio/gpio-vf610.c                          | 151 +++++++++++++++++++++
>  2 files changed, 157 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/gpio/gpio-vf610.txt b/Documentation/devicetree/bindings/gpio/gpio-vf610.txt
> index 436cc99..985ddfd 100644
> --- a/Documentation/devicetree/bindings/gpio/gpio-vf610.txt
> +++ b/Documentation/devicetree/bindings/gpio/gpio-vf610.txt
> @@ -22,6 +22,12 @@ Required properties for GPIO node:
>        4 = active high level-sensitive.
>        8 = active low level-sensitive.
>  
> +Option properties:

Optional

> +- fsl,gpio-wakeup : map GPIOs to WKPU unit, 3 argument cells per phandle

phandle to what?

> +      cell 1: First GPIO (relative to the GPIO block)
> +      cell 2: First GPIO of the WKPU unit
> +      cell 3: Number of consecutive GPIO's

An interrupt-map could work here instead even though I'm guessing you 
don't make the WKPU an interrupt parent. Your table would look something 
like this:

<WKPU# <&gpio> GPIO#>

> +
>  Note: Each GPIO port should have an alias correctly numbered in "aliases"
>  node.
>  
> diff --git a/drivers/gpio/gpio-vf610.c b/drivers/gpio/gpio-vf610.c
> index 1a022be..650a41a 100644
> --- a/drivers/gpio/gpio-vf610.c
> +++ b/drivers/gpio/gpio-vf610.c

The WKPU seems to purely be an interrupt controller. Perhaps you should 
use stacked irq domain here. Then it would not be tied into the GPIO 
controller at all.

Rob