From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933176AbcILN60 (ORCPT ); Mon, 12 Sep 2016 09:58:26 -0400 Received: from mail-wm0-f49.google.com ([74.125.82.49]:35488 "EHLO mail-wm0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932862AbcILN6U (ORCPT ); Mon, 12 Sep 2016 09:58:20 -0400 Date: Mon, 12 Sep 2016 15:00:15 +0100 From: Lee Jones To: Olimpiu Dejeu Cc: Rob Herring , linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, devicetree@vger.kernel.org, jg1.han@samsung.com Subject: Re: [PATCH] backlight: arcxcnn: devicetree bindings for ArticSand devices Message-ID: <20160912140015.GF9789@dell> References: <1471893084-4551-1-git-send-email-olimpiu@arcticsand.com> <20160823182057.GA8472@rob-hp-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.6.2 (2016-07-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 09 Sep 2016, Olimpiu Dejeu wrote: > On Tue, Aug 23, 2016 at 2:20 PM, Rob Herring wrote: > > > On Mon, Aug 22, 2016 at 03:11:24PM -0400, Olimpiu Dejeu wrote: > > > This is the device tree bindings documentation file > > > > > > Signed-off-by: Olimpiu Dejeu > > > > > > --- > > > .../bindings/video/backlight/arcxcnn.txt | 29 > > ++++++++++++++++++++++ > > > > > Check your directory location. Things have moved. > > > > Not sure what you mean. This seems to be the right place. Please advise. What kernel version are you on? Documentation/devicetree/bindings/leds/backlight > > > 1 file changed, 29 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/video/backlight/ > > arcxcnn.txt > > > > > > diff --git a/Documentation/devicetree/bindings/video/backlight/arcxcnn.txt > > b/Documentation/devicetree/bindings/video/backlight/arcxcnn.txt > > > new file mode 100644 > > > index 0000000..9cd7315 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/video/backlight/arcxcnn.txt > > > @@ -0,0 +1,29 @@ > > > +arcxcnn bindings > > > + > > > +Required properties: > > > + - compatible: "arc,arcxcnn", "arc,arc2c0608" > > > > One per line please. > > > > Is arcxcnn a specific chip? If not drop it. No wildcards in compatible > > strings. > > > > Wild-cards can be dropped but there could be a large family of similar > chips that would be supported with this one driver. How would one add > support for a range of chips, some of which don't exist yet? If they do not exist, then do not mention them in this document. Every other chip needs to be named individually. [...] > > > + - pwm-period: PWM period value. Set only PWM input mode used (u32) > > > + - prg-addr: Register address of ROM area to be updated (u32) low 8 > > bits used > > > + - prg-val: Register value to be updated (u32) low 8 bits used > > > > What is this for? This should be a specific property or properties to do > > explicit things, not a generic fill registers/rom with magic values. > > > > We need to expose some registers for test without exposing underlying > functionality. Do you suggest not documenting this in the bindings yet > keeping the code in the driver? We followed the pattern from the lp855x_bl > driver. If you are supplying addresses, use the reg property. > > > + > > > +Example: > > > + > > > + /* ARC2C0608 */ > > > + backlight@30 { > > > + compatible = "arc,arc2c0608"; > > > + reg = <0x30>; > > > + > > > + init-brt = <123>; > > > + > > > + /* LED0+1 string enabled */ > > > + prg_06h { > > > + prg-addr = <0x06>; > > > + prg-val = <0x83>; > > > + }; > > > + > > > + }; > > > > > -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog