From mboxrd@z Thu Jan 1 00:00:00 1970 From: robh@kernel.org (Rob Herring) Date: Fri, 12 Feb 2016 09:04:30 -0600 Subject: [PATCH 1/3] input: cygnus-update touchscreen dt node document In-Reply-To: <979fb4dc5fba643a6780759d2a13530a@mail.gmail.com> References: <1455008277-8312-1-git-send-email-raveendra.padasalagi@broadcom.com> <1455008277-8312-2-git-send-email-raveendra.padasalagi@broadcom.com> <2631849.GeOulu78vx@wuerfel> <3b53af6b6c6735d10cb88518c8b8a0ae@mail.gmail.com> <20160209174351.GC40460@dtor-ws> <979fb4dc5fba643a6780759d2a13530a@mail.gmail.com> Message-ID: <20160212150430.GA15049@rob-hp-laptop> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 at gmail.com] > > Sent: 09 February 2016 23:14 > > To: Raveendra Padasalagi > > Cc: Arnd Bergmann; Russell King; devicetree at vger.kernel.org; linux-arm- > > kernel at lists.infradead.org; linux-input at 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 at vger.kernel.org; > > bcm-kernel-feedback-list at 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