From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: Re: [PATCH 0/2] i2c: meson: add support for Meson G12A SoC i2c controller Date: Tue, 11 Dec 2018 13:41:25 -0800 Message-ID: <7hsgz3u4fu.fsf@baylibre.com> References: <1543489197-183181-1-git-send-email-jian.hu@amlogic.com> <8a6a204b28523e5a181f9e85dda18fade76a26a3.camel@baylibre.com> <20181211203652.rogajl4ajwu7cs6f@ninjato> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <20181211203652.rogajl4ajwu7cs6f@ninjato> Sender: linux-kernel-owner@vger.kernel.org To: Wolfram Sang , Jian Hu Cc: Jerome Brunet , Neil Armstrong , Carlo Caione , Rob Herring , Martin Blumenstingl , Michael Turquette , Stephen Boyd , Mark Rutland , Jianxin Pan , Hanjie Lin , linux-amlogic@lists.infradead.org, linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org Wolfram Sang writes: >> I am okay if it is reasonable below in file >> arch/arm64/boot/dts/amlogic/meson-g12a.dtsi. I2c controller node just uses >> axg's compatible. >> >> i2c0: i2c@1f000 { >> compatible = "amlogic,meson-axg-i2c"; > > Actually, you should have > > compatible = "amlogic,meson-g12a-i2c", "amlogic,meson-axg-i2c"; > > in the DT to have support for future SoC specific additions. And then, > patch 1 is needed. > > Or do you handle this differently? I'd think this is DT standard. It's a DT standard *if* there are actual hardware differences. In this case, the IP block is identical, so there are no driver changes. We prefer to add a new compatible if and when there are actual driver/hardware changes. Kevin