From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758888Ab3E1WFR (ORCPT ); Tue, 28 May 2013 18:05:17 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:56563 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756411Ab3E1WFP (ORCPT ); Tue, 28 May 2013 18:05:15 -0400 Message-ID: <51A52A16.1040204@wwwdotorg.org> Date: Tue, 28 May 2013 16:05:10 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-Version: 1.0 To: Jon Hunter CC: Afzal Mohammed , Russell King , linux-doc@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org, Rob Herring , Grant Likely , Benoit Cousson , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 11/14] Documentation: dt: binding: omap: am43x timer References: <223d90dc9eeab13d8496690d336cdf0f7d27cd22.1369658705.git.afzal@ti.com> <51A520B5.8040803@gmail.com> In-Reply-To: <51A520B5.8040803@gmail.com> X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/28/2013 03:25 PM, Jon Hunter wrote: > > On 27/05/13 15:37, Afzal Mohammed wrote: >> AM43x timer bindings. >> >> Signed-off-by: Afzal Mohammed >> --- >> Documentation/devicetree/bindings/arm/omap/timer.txt | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/arm/omap/timer.txt b/Documentation/devicetree/bindings/arm/omap/timer.txt >> index d02e27c..70cb398 100644 >> --- a/Documentation/devicetree/bindings/arm/omap/timer.txt >> +++ b/Documentation/devicetree/bindings/arm/omap/timer.txt >> @@ -14,6 +14,8 @@ Required properties: >> ti,omap5430-timer (applicable to OMAP543x devices) >> ti,am335x-timer (applicable to AM335x devices) >> ti,am335x-timer-1ms (applicable to AM335x devices) >> + "ti,am4372-timer-1ms", "ti,am335x-timer-1ms" for AM43x 1ms timer >> + "ti,am4372-timer", "ti,am335x-timer" for AM43x timers other than 1ms one >> >> - reg: Contains timer register address range (base address and >> length). > > If you are adding more compatibility strings, then this implies that the > AM43x timers are not 100% compatible with any other device listed (such > as am335x or any omap device). That's fine but you should state that in > the changelog. If the AM43x timer registers are 100% compatible with > existing devices you should not add these. I'm not sure that's true; .dts files should always include a compatible value that describes the most specific model of the HW, plus any baseline compatible value that the HW is compatible with. This allows any required quirks/fixes/... to be applied for the specific HW model later even if nobody knows right now they'll be needed. Hence, defining new compatible values doesn't necessarily mean incompatible HW. From mboxrd@z Thu Jan 1 00:00:00 1970 From: swarren@wwwdotorg.org (Stephen Warren) Date: Tue, 28 May 2013 16:05:10 -0600 Subject: [PATCH v2 11/14] Documentation: dt: binding: omap: am43x timer In-Reply-To: <51A520B5.8040803@gmail.com> References: <223d90dc9eeab13d8496690d336cdf0f7d27cd22.1369658705.git.afzal@ti.com> <51A520B5.8040803@gmail.com> Message-ID: <51A52A16.1040204@wwwdotorg.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 05/28/2013 03:25 PM, Jon Hunter wrote: > > On 27/05/13 15:37, Afzal Mohammed wrote: >> AM43x timer bindings. >> >> Signed-off-by: Afzal Mohammed >> --- >> Documentation/devicetree/bindings/arm/omap/timer.txt | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/arm/omap/timer.txt b/Documentation/devicetree/bindings/arm/omap/timer.txt >> index d02e27c..70cb398 100644 >> --- a/Documentation/devicetree/bindings/arm/omap/timer.txt >> +++ b/Documentation/devicetree/bindings/arm/omap/timer.txt >> @@ -14,6 +14,8 @@ Required properties: >> ti,omap5430-timer (applicable to OMAP543x devices) >> ti,am335x-timer (applicable to AM335x devices) >> ti,am335x-timer-1ms (applicable to AM335x devices) >> + "ti,am4372-timer-1ms", "ti,am335x-timer-1ms" for AM43x 1ms timer >> + "ti,am4372-timer", "ti,am335x-timer" for AM43x timers other than 1ms one >> >> - reg: Contains timer register address range (base address and >> length). > > If you are adding more compatibility strings, then this implies that the > AM43x timers are not 100% compatible with any other device listed (such > as am335x or any omap device). That's fine but you should state that in > the changelog. If the AM43x timer registers are 100% compatible with > existing devices you should not add these. I'm not sure that's true; .dts files should always include a compatible value that describes the most specific model of the HW, plus any baseline compatible value that the HW is compatible with. This allows any required quirks/fixes/... to be applied for the specific HW model later even if nobody knows right now they'll be needed. Hence, defining new compatible values doesn't necessarily mean incompatible HW.