From patchwork Mon Mar 5 02:56:50 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baolin Wang X-Patchwork-Id: 881280 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=linaro.org header.i=@linaro.org header.b="JW+tBuFt"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3zvl390HVkz9sZM for ; Mon, 5 Mar 2018 13:58:29 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932656AbeCEC5k (ORCPT ); Sun, 4 Mar 2018 21:57:40 -0500 Received: from mail-pl0-f65.google.com ([209.85.160.65]:40107 "EHLO mail-pl0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932634AbeCEC5j (ORCPT ); Sun, 4 Mar 2018 21:57:39 -0500 Received: by mail-pl0-f65.google.com with SMTP id i6-v6so8880906plt.7 for ; Sun, 04 Mar 2018 18:57:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=z2RKDZfloKH5HwHbF8v3xh8x4VoTv3dLoVSSj473NlM=; b=JW+tBuFtyz8nrQLrijSVkSSen7gOGioO+JqyN78RU1f7zSZbbqFKj2JFy6yI8VFuOp u56FC8PwvLXVTuP9Q6iwKOyKauROtCGjobKYGofEq7QXp39mQLjHKkpeb8zqZZqoXfKP vf7dNW7XmsPENNxrB3PJSQYshmVMo0JvIpQJU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=z2RKDZfloKH5HwHbF8v3xh8x4VoTv3dLoVSSj473NlM=; b=fh7sBG/bRsnQdZz0d1alsbEhmF6Gzj+P87KtKrQIGNiNkr6WOo+gwngEoqIvJMemyj 1/+E2JrWyHblrNdsBIWdpOKwchh9izXJr05WnblCxOM3RUraJFPwo8ZjnIQuXvnVU3bB hUyXp3SYGnkawLFo5aAE1FQIiOsMDmLemJXz/Rm70S9IVNLcbete7l0aBkrfgZO+u4i9 spqGA3talUUV4OsjqliFI+rhCLoiFXJOZLPnh8CHeFfXh4mFIM46PZZqUAsql7vzI9/l 3FQATVD4tKEUDVQSpwpCPI5s7TSFQCYnx04RtXis26e9HgTWT2AMUnoJeVMIch1DXBu3 bGYA== X-Gm-Message-State: APf1xPChiqUaHAF32kx1y0vthMkKss8s3HTsxPnXX2zVyatk0obKmseR SFwiI4axXKD3LRgIFExPvPO8Ew== X-Google-Smtp-Source: AG47ELsTUEOahiqlFmxqZeh3/pUCVUHciNtR5eXI06ZK8UwhwNg2f2kxbmjMV0HUDdlKy39pteRNxQ== X-Received: by 2002:a17:902:d204:: with SMTP id t4-v6mr11909314ply.377.1520218659394; Sun, 04 Mar 2018 18:57:39 -0800 (PST) Received: from baolinwangubtpc.spreadtrum.com ([117.18.48.82]) by smtp.gmail.com with ESMTPSA id p6sm22266571pfg.183.2018.03.04.18.57.35 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sun, 04 Mar 2018 18:57:38 -0800 (PST) From: Baolin Wang To: linus.walleij@linaro.org, robh+dt@kernel.org, mark.rutland@arm.com Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org, broonie@kernel.org, baolin.wang@linaro.org, andy.shevchenko@gmail.com Subject: [PATCH v3 1/3] dt-bindings: gpio: Add Spreadtrum EIC controller documentation Date: Mon, 5 Mar 2018 10:56:50 +0800 Message-Id: <787c9f115db06390549bfee366b7f70faf312286.1520218279.git.baolin.wang@linaro.org> X-Mailer: git-send-email 1.7.9.5 Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org This patch adds the device tree bindings for the Spreadtrum EIC controller. The EIC can be seen as a special type of GPIO, which can only be used as input mode. Signed-off-by: Baolin Wang Reviewed-by: Rob Herring --- Changes since v2: - Add reviewed tag from Rob. Changes since v1: - Fix some typos and grammar issues. - Add more explanation to make things clear. - List all device nodes as examples. --- .../devicetree/bindings/gpio/gpio-eic-sprd.txt | 97 ++++++++++++++++++++ 1 file changed, 97 insertions(+) create mode 100644 Documentation/devicetree/bindings/gpio/gpio-eic-sprd.txt diff --git a/Documentation/devicetree/bindings/gpio/gpio-eic-sprd.txt b/Documentation/devicetree/bindings/gpio/gpio-eic-sprd.txt new file mode 100644 index 0000000..93d98d0 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-eic-sprd.txt @@ -0,0 +1,97 @@ +Spreadtrum EIC controller bindings + +The EIC is the abbreviation of external interrupt controller, which can +be used only in input mode. The Spreadtrum platform has 2 EIC controllers, +one is in digital chip, and another one is in PMIC. The digital chip EIC +controller contains 4 sub-modules: EIC-debounce, EIC-latch, EIC-async and +EIC-sync. But the PMIC EIC controller contains only one EIC-debounce sub- +module. + +The EIC-debounce sub-module provides up to 8 source input signal +connections. A debounce mechanism is used to capture the input signals' +stable status (millisecond resolution) and a single-trigger mechanism +is introduced into this sub-module to enhance the input event detection +reliability. In addition, this sub-module's clock can be shut off +automatically to reduce power dissipation. Moreover the debounce range +is from 1ms to 4s with a step size of 1ms. The input signal will be +ignored if it is asserted for less than 1 ms. + +The EIC-latch sub-module is used to latch some special power down signals +and generate interrupts, since the EIC-latch does not depend on the APB +clock to capture signals. + +The EIC-async sub-module uses a 32kHz clock to capture the short signals +(microsecond resolution) to generate interrupts by level or edge trigger. + +The EIC-sync is similar with GPIO's input function, which is a synchronized +signal input register. It can generate interrupts by level or edge trigger +when detecting input signals. + +Required properties: +- compatible: Should be one of the following: + "sprd,sc9860-eic-debounce", + "sprd,sc9860-eic-latch", + "sprd,sc9860-eic-async", + "sprd,sc9860-eic-sync", + "sprd,sc27xx-eic". +- reg: Define the base and range of the I/O address space containing + the GPIO controller registers. +- gpio-controller: Marks the device node as a GPIO controller. +- #gpio-cells: Should be <2>. The first cell is the gpio number and + the second cell is used to specify optional parameters. +- interrupt-controller: Marks the device node as an interrupt controller. +- #interrupt-cells: Should be <2>. Specifies the number of cells needed + to encode interrupt source. +- interrupts: Should be the port interrupt shared by all the gpios. + +Example: + eic_debounce: gpio@40210000 { + compatible = "sprd,sc9860-eic-debounce"; + reg = <0 0x40210000 0 0x80>; + gpio-controller; + #gpio-cells = <2>; + interrupt-controller; + #interrupt-cells = <2>; + interrupts = ; + }; + + eic_latch: gpio@40210080 { + compatible = "sprd,sc9860-eic-latch"; + reg = <0 0x40210080 0 0x20>; + gpio-controller; + #gpio-cells = <2>; + interrupt-controller; + #interrupt-cells = <2>; + interrupts = ; + }; + + eic_async: gpio@402100a0 { + compatible = "sprd,sc9860-eic-async"; + reg = <0 0x402100a0 0 0x20>; + gpio-controller; + #gpio-cells = <2>; + interrupt-controller; + #interrupt-cells = <2>; + interrupts = ; + }; + + eic_sync: gpio@402100c0 { + compatible = "sprd,sc9860-eic-sync"; + reg = <0 0x402100c0 0 0x20>; + gpio-controller; + #gpio-cells = <2>; + interrupt-controller; + #interrupt-cells = <2>; + interrupts = ; + }; + + pmic_eic: gpio@300 { + compatible = "sprd,sc27xx-eic"; + reg = <0x300>; + interrupt-parent = <&sc2731_pmic>; + interrupts = <5 IRQ_TYPE_LEVEL_HIGH>; + gpio-controller; + #gpio-cells = <2>; + interrupt-controller; + #interrupt-cells = <2>; + };