From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH] ASoC: tda998x: Fix lack of required reg in DT documentation Date: Thu, 20 Mar 2014 16:22:58 +0000 Message-ID: <20140320162258.GX7528@n2100.arm.linux.org.uk> References: <20140320092639.48F68A6279@smtp3-g21.free.fr> <532ADFD8.80301@gmail.com> <20140320140156.5d768b1f@armhf> <532AEDE2.3080306@gmail.com> <20140320145221.09252bf6@armhf> <20140320143110.GU7528@n2100.arm.linux.org.uk> <20140320155935.7a474173@armhf> <20140320151934.GV7528@n2100.arm.linux.org.uk> <20140320165440.195cd2ea@armhf> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20140320165440.195cd2ea@armhf> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Jean-Francois Moine Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, dri-devel@lists.freedesktop.org, Sebastian Hesselbarth List-Id: devicetree@vger.kernel.org On Thu, Mar 20, 2014 at 04:54:40PM +0100, Jean-Francois Moine wrote: > On Thu, 20 Mar 2014 15:19:34 +0000 > Russell King - ARM Linux wrote: > > > I'm not saying that it has to match the physical device fitted - I'm > > merely suggesting not using nxp,tda1998x which could (and as Sebastian > > has found, does) conflict with other devices with different properties. > > > > We still auto-detect the exact device type by reading the ID register > > because that's the most reliable way to detect exactly what kind of > > device is fitted to the board. > > I don't see the problem. > > Actually the driver handles the tda9989, tda19988 and tda19989 (2 > variants). If some board has, for example, the tda9983 and if the > driver is extended to handle this chip (i.e. mainly ignore the CEC > part), setting 'nxp,tda998x' in the associated DT will still work. So you have to encode in the driver that if you see a tda9983 device, you don't touch the CEC part. Now think about how you'd handle a tda998x compatible device but with the CEC stuff at a different I2C address. -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it.