Re: [PATCH 1/3] input: cygnus-update touchscreen dt node document

Rob Herring
2016-02-12T15:04:43Z

Your mailer is not handling wrapping correctly. Generally, Outlook does
not work for maillists.

On Wed, Feb 10, 2016 at 10:24:43AM +0530, Raveendra Padasalagi wrote:
> > -----Original Message-----
> > From: Dmitry Torokhov [mailto:dmitry.torokhov@gmail.com]
> > Sent: 09 February 2016 23:14
> > To: Raveendra Padasalagi
> > Cc: Arnd Bergmann; Russell King; devicetree@vger.kernel.org; linux-arm-
> > kernel@lists.infradead.org; linux-input@vger.kernel.org; Rob Herring;
> Pawel
> > Moll; Mark Rutland; Ian Campbell; Kumar Gala; Jonathan Richardson; Jon
> > Mason; Florian Fainelli; Ray Jui; Scott Branden;
> linux-kernel@vger.kernel.org;
> > bcm-kernel-feedback-list@broadcom.com
> > Subject: Re: [PATCH 1/3] input: cygnus-update touchscreen dt node
> document

And Outlook's reply header is non-standard.

[...]

> > > In Cygnus SOC, Touch screen controller registers are shared with ADC
> > > and flex timer IP's.
> > > Using readl/writel could lead to race condition. So this patch is
> > > introduced to take care mutually exclusive access of register's in
> > > such a case.
> > >
> > > In the platform's where touchscreen register's are not shared normal
> > > readl/writel could be used.
> >
> > Are there currently platforms where the registers are not shared? If we
> have to
> > use regmap to correctly update registers (and thus we need
> > syscon) then I wonder if we should even attempt to support direct
> register
> > access by the driver.
>
> Currently there are no platforms without register sharing, but we would
> like to keep
> the driver generic enough to take care of future SOC's if comes with
> dedicated registers
> and same touchscreen IP being re-used.

These future SoCs will have a different compatible string and you should
use that to determine whether reg or syscon is used.

Rob