From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753359AbdEPALq (ORCPT ); Mon, 15 May 2017 20:11:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:45334 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753149AbdEPALn (ORCPT ); Mon, 15 May 2017 20:11:43 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0143E239BE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=robh+dt@kernel.org MIME-Version: 1.0 In-Reply-To: <87shk53bxq.fsf@eliezer.anholt.net> References: <20170511235625.22427-1-eric@anholt.net> <20170511235625.22427-3-eric@anholt.net> <1579603.xgvSgGFBs8@avalon> <87shk53bxq.fsf@eliezer.anholt.net> From: Rob Herring Date: Mon, 15 May 2017 19:11:21 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 2/4] dt-bindings: Document the Raspberry Pi Touchscreen nodes. To: Eric Anholt Cc: Laurent Pinchart , dri-devel , Thierry Reding , Mark Rutland , Archit Taneja , Andrzej Hajda , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 15, 2017 at 7:03 PM, Eric Anholt wrote: > Laurent Pinchart writes: > >> Hi Eric, >> >> Thank you for the patch. >> >> On Thursday 11 May 2017 16:56:23 Eric Anholt wrote: >>> The Raspberry Pi 7" Touchscreen is a DPI touchscreen panel with >>> DSI->DPI bridge and touchscreen controller integrated, that connects >>> to the Raspberry Pi through its 15-pin "DSI" connector (some lines are >>> DSI, some lines are I2C). >>> >>> This device is represented in the DT as three nodes (DSI device, I2C >>> device, panel). Input will be left to a separate binding later, as it >>> will be a basic I2C client device. >>> >>> Signed-off-by: Eric Anholt >>> --- >>> .../raspberrypi,7inch-touchscreen-bridge.txt | 68 +++++++++++++++++++ >>> .../panel/raspberrypi,7inch-touchscreen-panel.txt | 7 +++ >>> 2 files changed, 75 insertions(+) >>> create mode 100644 >>> Documentation/devicetree/bindings/display/bridge/raspberrypi,7inch-touchscr >>> een-bridge.txt create mode 100644 >>> Documentation/devicetree/bindings/display/panel/raspberrypi,7inch-touchscre >>> en-panel.txt >>> >>> diff --git >>> a/Documentation/devicetree/bindings/display/bridge/raspberrypi,7inch-touchs >>> creen-bridge.txt >>> b/Documentation/devicetree/bindings/display/bridge/raspberrypi,7inch-touchs >>> creen-bridge.txt new file mode 100644 >>> index 000000000000..a5669beaf68f >>> --- /dev/null >>> +++ >>> b/Documentation/devicetree/bindings/display/bridge/raspberrypi,7inch-touchs >>> creen-bridge.txt @@ -0,0 +1,68 @@ >>> +Official 7" (800x480) Raspberry Pi touchscreen panel's bridge. >>> + >>> +This DSI panel contains: >>> + >>> +- TC358762 DSI->DPI bridge >>> +- Atmel microcontroller on I2C for power sequencing the DSI bridge and >>> + controlling backlight >>> +- Touchscreen controller on I2C for touch input >>> + >>> +and this covers the TC358762 bridge and Atmel microcontroller, while >>> +../panel/raspberrypi,7inch-touchscreen-panel.txt covers the panel. >> >> The TC358762 is a standalone bridge that doesn't depend on the ATTiny >> microcontroller used by the RPI. As it's usable standalone, I believe this >> binding should be split in two. > > Do you have a plan for how I would implement a driver on top of that > binding change, though? Note that we don't program the Toshiba > directly, we only send commands to the Atmel. I agree. If it is a black box and the interface to the host is defined by the Atmel uC firmware, then that's what the DT should describe. Perhaps a diagram here or pointer to one would help and remove mentioning what kind of bridge chip it is. Rob