From patchwork Thu Jan 11 19:44:25 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baruch Siach X-Patchwork-Id: 10158409 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 6CD10602D8 for ; Thu, 11 Jan 2018 19:46:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5BF142851E for ; Thu, 11 Jan 2018 19:46:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4FDF7285FC; Thu, 11 Jan 2018 19:46:04 +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=-4.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 13B302851E for ; Thu, 11 Jan 2018 19:46:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=3auG9b+T9qolQT/RdQ2jyTte9BluknnDybeqn20hlEs=; b=Ynd0bn8QB/4/vGB+ZZ8zg/dR/c aLwZqFYNMY3BylAUMColHR8aCgFVi4W+k8bRefOEy+zlGCbXH+sag214ExPEkO4i5bOIjkMZe/n3r sdKwHPM8f9WkAFHR+oOlamjrMsOfxSrQHmQeyb9vXQmXS170nfsIPWxxFZM2KzSmx7P5425bTZq/U WQ0XPw3aXXHpI80jkMyQ9oQzN9MrVKRxyvOOx9tMbyPmimBPpEJEIjKuiLQ3idzGyoQ9XqhFKPldA LrTfuU87R0U0PJclGnd4jx/bTOCPUoNbJ8MLl5U/2PKHQY2Kduo+kmRWXh0NlslbHi7i0F9xX1M2P gxIMK3wg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1eZinY-0001ye-62; Thu, 11 Jan 2018 19:46:00 +0000 Received: from guitar.tcltek.co.il ([192.115.133.116] helo=mx.tkos.co.il) by bombadil.infradead.org with esmtps (Exim 4.89 #1 (Red Hat Linux)) id 1eZinS-0001uK-B1; Thu, 11 Jan 2018 19:45:57 +0000 Received: from tarshish.tkos.co.il (unknown [10.0.8.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx.tkos.co.il (Postfix) with ESMTPSA id 136234403B5; Thu, 11 Jan 2018 21:45:19 +0200 (IST) From: Baruch Siach To: Dave Stevenson , Eric Anholt , Stefan Wahren , Linus Walleij Subject: [PATCH v2 2/4] dt-bindings: gpio: add raspberry pi GPIO expander binding Date: Thu, 11 Jan 2018 21:44:25 +0200 Message-Id: X-Mailer: git-send-email 2.15.1 In-Reply-To: References: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180111_114554_722230_978DB314 X-CRM114-Status: GOOD ( 10.96 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Baruch Siach , linux-gpio@vger.kernel.org, Michael Zoran , linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The Raspberry Pi 3 GPIO expander is controlled by the VC4 firmware over I2C. The firmware mailbox interface allows the ARM core to control the GPIO lines. Signed-off-by: Baruch Siach --- v2: * Rename compatible string to raspberrypi,firmware-gpio --- .../bindings/gpio/raspberrypi,firmware-gpio.txt | 24 ++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt diff --git a/Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt b/Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt new file mode 100644 index 000000000000..8faf269cf541 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/raspberrypi,firmware-gpio.txt @@ -0,0 +1,24 @@ +Raspberry Pi GPIO expander + +The Raspberry Pi 3 GPIO expander is controlled by the VC4 firmware. The +firmware exposes a mailbox interface that allows the ARM core to control the +GPIO lines on the expander. + +Required properties: + +- compatible : Should be "raspberrypi,firmware-gpio" +- gpio-controller : Marks the device node as a gpio controller +- #gpio-cells : Should be two. The first cell is the pin number, and + the second cell is used to specify the gpio polarity: + 0 = active high + 1 = active low +- firmware : Reference to the RPi firmware device node + +Example: + +expgpio: expgpio { + compatible = "raspberrypi,firmware-gpio"; + gpio-controller; + #gpio-cells = <2>; + firmware = <&firmware>; +};