From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [RFC PATCH v2 1/4] dt-bindings: input: Add support for the MPR121 without interrupt line Date: Sat, 27 Jul 2019 11:01:54 +0300 Message-ID: <20190727080154.GB795@penguin> References: <1558098773-47416-1-git-send-email-michal.vokac@ysoft.com> <1558098773-47416-2-git-send-email-michal.vokac@ysoft.com> <20190613223945.GA938@bogus> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <20190613223945.GA938@bogus> Sender: linux-kernel-owner@vger.kernel.org To: Rob Herring Cc: Michal =?utf-8?B?Vm9rw6HEjQ==?= , Mark Rutland , Shawn Guo , Sascha Hauer , Fabio Estevam , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Pengutronix Kernel Team List-Id: devicetree@vger.kernel.org On Thu, Jun 13, 2019 at 04:39:45PM -0600, Rob Herring wrote: > On Fri, May 17, 2019 at 03:12:50PM +0200, Michal Vokáč wrote: > > Normally, the MPR121 controller uses separate interrupt line to notify > > the I2C host that a key was touched/released. To support platforms that > > can not use the interrupt line, polling of the MPR121 registers can be > > used. > > 'separate' from what? > > > > > Signed-off-by: Michal Vokáč > > --- > > Changes since v1: > > - Document the polled binding in the original file, do not create a new one. > > (Rob) > > > > Documentation/devicetree/bindings/input/mpr121-touchkey.txt | 9 +++++++-- > > 1 file changed, 7 insertions(+), 2 deletions(-) > > > > diff --git a/Documentation/devicetree/bindings/input/mpr121-touchkey.txt b/Documentation/devicetree/bindings/input/mpr121-touchkey.txt > > index b7c61ee5841b..97f55273d473 100644 > > --- a/Documentation/devicetree/bindings/input/mpr121-touchkey.txt > > +++ b/Documentation/devicetree/bindings/input/mpr121-touchkey.txt > > @@ -1,9 +1,14 @@ > > -* Freescale MPR121 Controllor > > +* Freescale MPR121 Controller > > > > Required Properties: > > -- compatible: Should be "fsl,mpr121-touchkey" > > +- compatible: Should be one of: > > + - "fsl,mpr121-touchkey" - MPR121 with interrupt line > > + - "fsl,mpr121-touchkey-polled" - MPR121 with polling > > - reg: The I2C slave address of the device. > > - interrupts: The interrupt number to the cpu. > > + In case of "fsl,mpr121-touchkey-polled" the interrupt > > + line is not used and hence the interrupts property is > > + not required. > > Absence of the interrupts property is enough to determine polled mode > and you don't need a separate compatible string. I would prefer if we could distinguish between chip working in polled mode intentionally vs DT writer simply forgetting to specify interrupt property. Should we key the polling mode off "linux,poll-interval" property? We probably going to need it anyway as not everyone needs the same polling frequency. Thanks. -- Dmitry