From mboxrd@z Thu Jan  1 00:00:00 1970
From: marex@denx.de (Marek Vasut)
Date: Sat, 14 Dec 2013 15:16:29 +0100
Subject: [PATCH V1 05/11] ARM: dts: imx6qdl-sabrelite: specify pad settings
In-Reply-To: <20131214132905.GB16177@S2101-09.ap.freescale.net>
References: <1386899355-17379-1-git-send-email-troy.kisky@boundarydevices.com>
 <201312132250.29518.marex@denx.de>
 <20131214132905.GB16177@S2101-09.ap.freescale.net>
Message-ID: <201312141516.29435.marex@denx.de>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Saturday, December 14, 2013 at 02:29:07 PM, Shawn Guo wrote:
> On Fri, Dec 13, 2013 at 10:50:29PM +0100, Marek Vasut wrote:
> > On Friday, December 13, 2013 at 07:42:25 PM, Troy Kisky wrote:
> > > On 12/13/2013 4:48 AM, Marek Vasut wrote:
> > > > On Friday, December 13, 2013 at 02:49:09 AM, Troy Kisky wrote:
> > > >> Don't use 0x80000000 to get default pad settings.
> > > > 
> > > > What is the rationale behind this change please? Can you explain more
> > > > in detail?
> > > 
> > > No real need, but I thought relying on what the boot loader did or did
> > > not do
> > > was discouraged?
> > 
> > Full ACK on this, we do not rely on bootloader configuration (though
> > these two should be in-line).
> > 
> > > What is the value in not explicitly setting the pad registers?
> > 
> > My question was in the direction of "why do you need to change the pin
> > configuration values from the current ones?". This is what I want to
> > understand.
> > 
> > > Btw, I need to rebase series on your patch anyway so omitting this
> > > patch would be easy.
> > 
> > I am not saying to omit it, please do not misunderstand me. I am just
> > wondering why the change from 0x80000000 to 0x1b0b0 .
> 
> Per Documentation/devicetree/bindings/pinctrl/fsl,imx-pinctrl.txt,
> 
>  Bits used for CONFIG:
>  NO_PAD_CTL(1 << 31): indicate this pin does not need config.
> 
> 0x80000000 tells pinctrl driver to not touch pad config register at all.
> In that case, the configuration of the pad will be what boot loader
> configures or just the reset value.
> 
> Explicitly putting a proper pad config value instead of 0x80000000
> should be something we encourage.

Gotcha, thanks!

Best regards,
Marek Vasut