From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH v9 1/4] drm/i2c: tda998x: Add DT support for audio Date: Mon, 12 Jan 2015 12:25:27 +0000 Message-ID: <20150112122527.GF12302@n2100.arm.linux.org.uk> References: <54AFA9B0.6040405@ti.com> <20150109123036.4bc4bbf6@armhf> <20150109114529.GH12302@n2100.arm.linux.org.uk> <20150109135401.5b270d46@armhf> <20150109130725.GN12302@n2100.arm.linux.org.uk> <54AFDE8D.3000504@arm.com> <20150109145741.GP12302@n2100.arm.linux.org.uk> <20150109183857.53d701a4@armhf> <20150109200127.GD12302@n2100.arm.linux.org.uk> <1421054728.3081.28.camel@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1421054728.3081.28.camel@pengutronix.de> Sender: linux-kernel-owner@vger.kernel.org To: Philipp Zabel Cc: Jean-Francois Moine , Andrew Jackson , Jyri Sarha , Mark Brown , Dave Airlie , "alsa-devel@alsa-project.org" , "devicetree@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" List-Id: devicetree@vger.kernel.org On Mon, Jan 12, 2015 at 10:25:28AM +0100, Philipp Zabel wrote: > Jean-Francois' reply already reflects this, but the 'port' nodes should > correspond to physical ports of the device if possible. If you can > configure the device to have dedicated input pins for I2S, SPDIF0, and > SPDIF1 at the same time, they should appear in the device tree as > separate ports: > > tda998x: hdmi-encoder { > port@0 { /* pixel data according to video-ports */ > reg = <0x00>; > }; > port@1 { /* AP1: SPDIF0 */ > reg = <0x01>; > }; > port@2 { /* AP2: SPDIF1 */ > reg = <0x02>; > }; > port@3 { /* AP3: I2S */ > reg = <0x03>; > }; > }; > > The tda998x binding would define how the ports are numbered, some > correspondence to the AP pin numbers would be good. It's not quite that simple, because the SPDIF AP pins are multiplexed with the I2S pins - and there is variation between chip models and packages. So, it's probably best if port@0 is the video port, and then port@1..n can describe the audio inputs, including a property which specifies whether they are I2S or SPDIF, and the value to be programmed into the AP enable register (which is a bit field of the AP pins which should be unmasked.) I guess we can re-use the reg= property for that value, since video will always be zero. -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net.