From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: Re: [PATCH v6 1/2] mtd: arasan: Add device tree binding documentation Date: Mon, 5 Dec 2016 17:11:36 +0100 Message-ID: <59e420fd-afb1-ab4c-44bd-ead160496bfd@gmail.com> References: <1480911066-26157-1-git-send-email-punnaia@xilinx.com> <74842d92-840d-a7c2-fb1b-ddab1ac2cf42@gmail.com> <20161205093630.650451d7@bbrezillon> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20161205093630.650451d7@bbrezillon> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Boris Brezillon Cc: Punnaiah Choudary Kalluri , dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, computersforpeace-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, richard-/L3Ra7n9ekc@public.gmane.org, cyrille.pitchen-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, michals-gjFFaj9aHVfQT0dZR+AlfA@public.gmane.org, kalluripunnaiahchoudary-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, kpc528-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Punnaiah Choudary Kalluri List-Id: devicetree@vger.kernel.org On 12/05/2016 09:36 AM, Boris Brezillon wrote: > On Mon, 5 Dec 2016 05:25:54 +0100 > Marek Vasut wrote: > >> On 12/05/2016 05:11 AM, Punnaiah Choudary Kalluri wrote: >>> This patch adds the dts binding document for arasan nand flash >>> controller. >>> >>> Signed-off-by: Punnaiah Choudary Kalluri >>> Acked-by: Rob Herring >>> --- >>> changes in v6: >>> - Removed num-cs property >>> - Separated nandchip from nand controller >>> changes in v5: >>> - None >>> Changes in v4: >>> - Added num-cs property >>> - Added clock support >>> Changes in v3: >>> - None >>> Changes in v2: >>> - None >>> --- >>> .../devicetree/bindings/mtd/arasan_nfc.txt | 38 ++++++++++++++++++++++ >>> 1 file changed, 38 insertions(+) >>> create mode 100644 Documentation/devicetree/bindings/mtd/arasan_nfc.txt >>> >>> diff --git a/Documentation/devicetree/bindings/mtd/arasan_nfc.txt b/Documentation/devicetree/bindings/mtd/arasan_nfc.txt >>> new file mode 100644 >>> index 0000000..dcbe7ad >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/mtd/arasan_nfc.txt >>> @@ -0,0 +1,38 @@ >>> +Arasan Nand Flash Controller with ONFI 3.1 support >> >> Arasan NAND Flash ... >> >>> +Required properties: >>> +- compatible: Should be "arasan,nfc-v3p10" >> >> This v3p10 looks like version 3 patchlevel 10, but shouldn't we have >> some fallback option which doesn't encode IP version in the compat >> string ? > > Not necessarily. Usually you define a generic compatible when you have > other reliable means to detect the IP version (a version register for > example). > If you can't detect that at runtime, then providing only specific > compatible strings is a good solution to avoid breaking the DT ABI. Can we detect it at runtime with this hardware ? >> >> Also, shouldn't quirks be handled by DT props instead of effectively >> encoding them into the compatible string ? > > Well, from my experience, it's better to hide as much as possible > behind the compatible. This way, if new quirks are needed for a > specific revision, you can update the driver without having to change > the DT. That's a good point, yes. -- Best regards, Marek Vasut -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html