From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guy Shapiro Subject: Re: [PATCH 1/2] Documentation: sample averaging for imx6ul_tsc Date: Thu, 8 Dec 2016 17:15:17 +0200 Message-ID: <82b04890-692d-4e22-36c1-a21affad5126@mobi-wize.com> References: <1480232698-23075-1-git-send-email-guy.shapiro@mobi-wize.com> <20161201161343.g7p2maxiatp4m5di@rob-hp-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20161201161343.g7p2maxiatp4m5di@rob-hp-laptop> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Rob Herring Cc: fabio.estevam@freescale.com, mark.rutland@arm.com, devicetree@vger.kernel.org, haibo.chen@freescale.com, dmitry.torokhov@gmail.com, linux-input@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org On 01/12/2016 18:13, Rob Herring wrote: > On Sun, Nov 27, 2016 at 09:44:57AM +0200, Guy Shapiro wrote: >> The i.MX6UL internal touchscreen controller contains an option to >> average upon samples. This feature reduces noise from the produced >> touch locations. >> >> This patch introduces a new device tree optional property for this >> feature. It provides control over the amount of averaged samples per >> touch event. >> >> The property was inspired by a similar property on the >> "brcm,iproc-touchscreen" binding. >> >> Signed-off-by: Guy Shapiro >> --- >> .../devicetree/bindings/input/touchscreen/imx6ul_tsc.txt | 8 > ++++++++ >> 1 file changed, 8 insertions(+) >> >> diff --git > a/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt > b/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt >> index 853dff9..a66069f 100644 >> --- a/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt >> +++ b/Documentation/devicetree/bindings/input/touchscreen/imx6ul_tsc.txt >> @@ -17,6 +17,13 @@ Optional properties: >> This value depends on the touch screen. >> - pre-charge-time: the touch screen need some time to precharge. >> This value depends on the touch screen. >> +- average-samples: Number of data samples which are averaged for each > read. >> + Valid values 0-4 >> + 0 = 1 sample >> + 1 = 4 samples >> + 2 = 8 samples >> + 3 = 16 samples >> + 4 = 32 samples > Either this needs a vendor prefix or should be documented as a generic > property. In the latter case, you should use actual number of samples > (1-32) for the values. In the term "generic property", do you mean to document it on bindings/input/touchscreen/touchscreen.txt ? If so, should I add the "touchscreen-" prefix like all the other properties in that file? Grepping bindings/input/touchscreen/, I found two other device drivers that implement a similar property - "ti-tsc-adc" and "brcm,iproc-touchscreen" (The latter, BTW, uses a non vendor prefixed property name). Do we want to move from per-vendor properties to a generic one? If we do, should we deprecate the existing vendor specific properties?