From mboxrd@z Thu Jan 1 00:00:00 1970 From: Javier Martinez Canillas Subject: Re: [RFC PATCH 1/4] spi: spidev: Add Google SPI flash compatible string Date: Wed, 20 May 2015 09:35:57 +0200 Message-ID: <555C395D.9080409@collabora.co.uk> References: <1432042454-19234-1-git-send-email-javier.martinez@collabora.co.uk> <1432042454-19234-2-git-send-email-javier.martinez@collabora.co.uk> <20150519195305.GA2586@tarshish> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150519195305.GA2586@tarshish> Sender: linux-samsung-soc-owner@vger.kernel.org To: Baruch Siach Cc: Mark Brown , Krzysztof Kozlowski , linux-samsung-soc@vger.kernel.org, Doug Anderson , linux-kernel@vger.kernel.org, Kukjin Kim , Olof Johansson , David Hendricks , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org Hello Baruch, On 05/19/2015 09:53 PM, Baruch Siach wrote: > Hi Javier, > > On Tue, May 19, 2015 at 03:34:11PM +0200, Javier Martinez Canillas wrote: >> Google Chromebooks have a SPI flash that is used to store firmware and >> different system parameters and data (i.e: Google Binary Block flags). >> >> Since there isn't a driver for it yet, the spidev interface is used to >> access the flash from user-space (i.e: using the flashrom tool). >> >> Add a "google,spi-flash" compatible string so the Device Tree sources >> use it instead of the "spidev" compatible which does not describe the >> real HW and is just a Linux implementation detail. >> >> A generic "google,spi-flash" OF device ID is used instead of the actual >> vendor/model because these chips are commodity parts that are sourced >> from multiple vendors. So specifying the exact vendor and model in the >> DTS will add a maintenance burden with no real gain (the parts are 100% >> compatible anyways) and will likely result in it simply being wrong for >> a sizeable fraction of the machines. > > The compatible string and dt binding should be documented somewhere under > Documentation/devicetree/bindings/. Also, please keep the dt list on Cc for dt > related patches. > Yes, I didn't add a binding doc because this is mostly a RFC to see if Mark finds the approach feasible but yes I should had included anyways, sorry about that. I'll add when posting as a proper patch if he agrees with the solution. > baruch > Best regards, Javier