From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: Re: [PATCH v7 5/5] ARM: OMAP: gpmc: add DT bindings for GPMC timings and NAND Date: Thu, 6 Dec 2012 10:22:30 -0600 Message-ID: <50C0C646.9000802@ti.com> References: <1354734571-10774-1-git-send-email-zonque@gmail.com> <1354734571-10774-6-git-send-email-zonque@gmail.com> <20121205222232.67B2B3E0E22@localhost> <50BFCBCC.6030706@ti.com> <20121205232426.BAD573E0E22@localhost> <20121206000302.GM21682@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20121206000302.GM21682-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: "devicetree-discuss" To: Tony Lindgren Cc: x0148406-l0cyMroinI0@public.gmane.org, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, nsekhar-l0cyMroinI0@public.gmane.org, rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org On 12/05/2012 06:03 PM, Tony Lindgren wrote: > * Grant Likely [121205 15:26]: >> On Wed, 5 Dec 2012 16:33:48 -0600, Jon Hunter wrote: >>> On 12/05/2012 04:22 PM, Grant Likely wrote: >>>> >>>> Please, be specific. Use something like "ti,am3340-gpmc" or >>>> "ti,omap3430-gpmc". The compatible property is a list so that new >>>> devices can claim compatibility with old. Compatible strings that are >>>> overly generic are a pet-peave of mine. >>> >>> We aim to use the binding for omap2,3,4,5 as well as the am33xx devices >>> (which are omap based). Would it be sufficient to have "ti,omap2-gpmc" >>> implying all omap2+ based devices or should we have a compatible string >>> for each device supported? >> >> Are they each register-level compatible with one another? >> >> The general recommended approach here is to make subsequent silicon >> claim compatibility with the first compatible implementation. >> >> So, for an am3358 board: >> compatible = "ti,am3358-gpmc", "ti,omap2420-gpmc"; >> >> Essentially, what this means is that "ti,omap2420-gpmc" is the generic >> value instead of "omap2-gpmc". The reason for this is so that the value >> is anchored against a specific implementation, and not against something >> completely imaginary or idealized. If a newer version isn't quite >> compatible with the omap2420-gpmc, then it can drop the compatible claim >> and the driver really should be told about the new device. > > The compatible property can also be used to figure out which ones > need the workarounds in patch #4 of this series for the DT case. > So we should be specific with the compatible. We should not merged patch #4. Daniel included this here because he is using this on the current mainline, however, this is not needed for linux-next and so we should drop it. Cheers Jon