From patchwork Fri Nov 16 16:23:48 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lubomir Rintel X-Patchwork-Id: 10686631 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A402613B5 for ; Fri, 16 Nov 2018 16:26:51 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8E8E32CE4E for ; Fri, 16 Nov 2018 16:26:51 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7DEED2CC21; Fri, 16 Nov 2018 16:26:51 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1D9992CE4E for ; Fri, 16 Nov 2018 16:26:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390120AbeKQChm (ORCPT ); Fri, 16 Nov 2018 21:37:42 -0500 Received: from shell.v3.sk ([90.176.6.54]:56992 "EHLO shell.v3.sk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729055AbeKQChl (ORCPT ); Fri, 16 Nov 2018 21:37:41 -0500 Received: from localhost (localhost [127.0.0.1]) by zimbra.v3.sk (Postfix) with ESMTP id C716552C13; Fri, 16 Nov 2018 17:24:35 +0100 (CET) Received: from shell.v3.sk ([127.0.0.1]) by localhost (zimbra.v3.sk [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id Dt3cM4g1-9ce; Fri, 16 Nov 2018 17:24:18 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by zimbra.v3.sk (Postfix) with ESMTP id 937E952D80; Fri, 16 Nov 2018 17:24:17 +0100 (CET) X-Virus-Scanned: amavisd-new at zimbra.v3.sk Received: from shell.v3.sk ([127.0.0.1]) by localhost (zimbra.v3.sk [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id v4soZBGxVrUG; Fri, 16 Nov 2018 17:24:14 +0100 (CET) Received: from belphegor.brq.redhat.com (nat-pool-brq-t.redhat.com [213.175.37.10]) by zimbra.v3.sk (Postfix) with ESMTPSA id 4A80252B71; Fri, 16 Nov 2018 17:24:14 +0100 (CET) From: Lubomir Rintel To: Mark Brown , Geert Uytterhoeven , Darren Hart , Andy Shevchenko Cc: Greg Kroah-Hartman , James Cameron , Sebastian Reichel , Rob Herring , Mark Rutland , Eric Miao , Haojian Zhuang , Daniel Mack , Robert Jarzmik , linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, platform-driver-x86@vger.kernel.org, devel@driverdev.osuosl.org, linux-pm@vger.kernel.org, Lubomir Rintel Subject: [PATCH v2 02/17] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings Date: Fri, 16 Nov 2018 17:23:48 +0100 Message-Id: <20181116162403.49854-3-lkundrak@v3.sk> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181116162403.49854-1-lkundrak@v3.sk> References: <20181116162403.49854-1-lkundrak@v3.sk> MIME-Version: 1.0 Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra signals for handshaking. It needs to know when is the slave (Linux) side's TX FIFO ready for transfer (the ready-gpio signal on the SPI controller node) and when does it wish to respond with a command (the cmd-gpio property). Signed-off-by: Lubomir Rintel Acked-by: Pavel Machek Reviewed-by: Rob Herring --- Changes since v1: - s/cmd-gpio/cmd-gpios/ - s/ready-gpio/ready-gpios/ in the documentation paragraph - Remove status = "okay" from the example .../bindings/misc/olpc,xo1.75-ec.txt | 23 +++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt diff --git a/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt new file mode 100644 index 000000000000..8c4d649cdd8f --- /dev/null +++ b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt @@ -0,0 +1,23 @@ +OLPC XO-1.75 Embedded Controller + +Required properties: +- compatible: Should be "olpc,xo1.75-ec". +- cmd-gpios: gpio specifier of the CMD pin + +The embedded controller requires the SPI controller driver to signal readiness +to receive a transfer (that is, when TX FIFO contains the response data) by +strobing the ACK pin with the ready signal. See the "ready-gpios" property of the +SSP binding as documented in: +. + +Example: + &ssp3 { + spi-slave; + ready-gpios = <&gpio 125 GPIO_ACTIVE_HIGH>; + + slave { + compatible = "olpc,xo1.75-ec"; + spi-cpha; + cmd-gpios = <&gpio 155 GPIO_ACTIVE_HIGH>; + }; + };