Received: by 10.223.185.116 with SMTP id b49csp362620wrg;
        Tue, 20 Feb 2018 23:00:19 -0800 (PST)
X-Google-Smtp-Source: AH8x225VT93sKRYIZ5HGB5fQjINN6JIwStOooxmdX1WxDQQviZumdJD94XXlJVwp3fMCDcsiC7sK
X-Received: by 10.99.182.12 with SMTP id j12mr1954431pgf.113.1519196419621;
        Tue, 20 Feb 2018 23:00:19 -0800 (PST)
ARC-Seal: i=1; a=rsa-sha256; t=1519196419; cv=none;
        d=google.com; s=arc-20160816;
        b=sBRJBia722oLp+YTca1iSPf/h1mYfr/HJbGWUb9N7iomswMBmBIWK1VoJX3zrqdVQM
         l7m02mv8XR/PZmVgSdXogDfTQ+dCgcnSm7rR7rWi+m8NhVw87/unFvawsJNtQAN/Gabn
         DjpNqf9i1ZuyIxtUeGCu3gM7bI47YSGhOvj52B0QnYuY0UnJmIurOk2W1lRez6Hpf1KH
         KzUHZYYWaVzgBFNqZsGaXo5I0tFxPvyAsW3TNItXZsVDOuACkI6R4iW+w89juRlfbplV
         n28kN2geTZVPzBmTtSfB5PQR3lXSb9i7Y0dx51+VGnvix/OSafFnXMzV6IZIWocsmlQI
         f06Q==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=list-id:precedence:sender:mime-version:message-id:date:subject:cc
         :to:from:arc-authentication-results;
        bh=08pxwqlhYD+9IoV0DNT5WDgqnOpnehFqxonQ5r8AMgw=;
        b=OvXzqOrNC+CkUZp13v4NRB/h2kuJcNFcIlnodnl0DlYjsn/g9lggfWv/DPXtjtttai
         l+rUo6jFnp7+vo3Oa1jpgujo47nfagcImP+gg9FNg4Upn/dTgKwv6h8KW+NoPGHRe1ku
         oDAU9I4NyIQSHPlkE0g9+nXOMZ+L5OSw59UPJqJQOYuP5XQUKEWrodufumuwScmtmfMy
         HZb+q5STzjGrKqlrgcBYS/8lEeAhIc94u9cD0FPmU6JKLngPMLozlpwh4XIV4tGjf7Yn
         BpWc6myl9YDC6P5YcGOK0e1SVhGMUbHz6/8uUj4RfJBJMD8Aneu631+4et97eq4qskag
         lYZg==
ARC-Authentication-Results: i=1; mx.google.com;
       spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org;
       dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=nvidia.com
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67])
        by mx.google.com with ESMTP id n68si5735589pga.524.2018.02.20.23.00.03;
        Tue, 20 Feb 2018 23:00:19 -0800 (PST)
Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Authentication-Results: mx.google.com;
       spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org;
       dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=nvidia.com
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1751501AbeBUG7U (ORCPT <rfc822;lans.zhang2008@gmail.com>
        + 99 others); Wed, 21 Feb 2018 01:59:20 -0500
Received: from hqemgate14.nvidia.com ([216.228.121.143]:16202 "EHLO
        hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1750752AbeBUG7S (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 21 Feb 2018 01:59:18 -0500
Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate14.nvidia.com
        id <B5a8d18c90000>; Tue, 20 Feb 2018 22:59:21 -0800
Received: from HQMAIL105.nvidia.com ([172.20.161.6])
  by hqpgpgate101.nvidia.com (PGP Universal service);
  Tue, 20 Feb 2018 22:59:16 -0800
X-PGP-Universal: processed;
        by hqpgpgate101.nvidia.com on Tue, 20 Feb 2018 22:59:16 -0800
Received: from BGMAIL101.nvidia.com (10.25.59.10) by HQMAIL105.nvidia.com
 (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 21 Feb
 2018 06:59:14 +0000
Received: from HQMAIL105.nvidia.com (172.20.187.12) by bgmail101.nvidia.com
 (10.25.59.10) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 21 Feb
 2018 06:59:11 +0000
Received: from rrajk-ubuntu.nvidia.com (10.124.1.5) by HQMAIL105.nvidia.com
 (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1347.2 via Frontend
 Transport; Wed, 21 Feb 2018 06:59:02 +0000
From:   Rajkumar Rampelli <rrajk@nvidia.com>
To:     <robh+dt@kernel.org>, <mark.rutland@arm.com>,
        <thierry.reding@gmail.com>, <jonathanh@nvidia.com>,
        <jdelvare@suse.com>, <linux@roeck-us.net>, <corbet@lwn.net>,
        <catalin.marinas@arm.com>, <will.deacon@arm.com>,
        <kstewart@linuxfoundation.org>, <gregkh@linuxfoundation.org>,
        <pombredanne@nexb.com>, <mmaddireddy@nvidia.com>,
        <mperttunen@nvidia.com>, <arnd@arndb.de>,
        <gregory.clement@free-electrons.com>, <timur@codeaurora.org>,
        <andy.gross@linaro.org>, <xuwei5@hisilicon.com>,
        <elder@linaro.org>, <heiko@sntech.de>, <krzk@kernel.org>,
        <ard.biesheuvel@linaro.org>
CC:     <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-pwm@vger.kernel.org>, <linux-tegra@vger.kernel.org>,
        <linux-hwmon@vger.kernel.org>, <linux-doc@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>, <ldewangan@nvidia.com>,
        <rrajk@nvidia.com>
Subject: [PATCH 00/10] Implementation of Tegra Tachometer driver
Date:   Wed, 21 Feb 2018 12:28:49 +0530
Message-ID: <1519196339-9377-1-git-send-email-rrajk@nvidia.com>
X-Mailer: git-send-email 2.1.4
MIME-Version: 1.0
Content-Type: text/plain
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

The following patches adds support for PWM based Tegra Tachometer driver
which implements PWM capture interface to analyze the PWM signal of a
electronic fan and reports it in periods and duty cycles.

Generic PWM Tachometer implemented to monitor the speed of fan in rpms
using PWM interface. RPM of Fan will be exposed to user interface through
HWMON sysfs interface avialable at below location
/sys/devices/platform/generic_pwm_tachometer/hwmon/hwmon0/rpm

Steps to validate Tachometer:
A. push modules pwm-tegra.ko, pwm-tegra-tachometer.ko and
   generic-pwm-tachometer.ko to linux device using scp command.
   scp build/tegra186/drivers/pwm/pwm-tegra.ko ubuntu@10.19.65.176:/tmp/
   scp build/tegra186/drivers/pwm/pwm-tegra-tachometer.ko ubuntu@10.19.65.176:/tmp/
   scp build/tegra186/drivers/hwmon/generic-pwm-tachometer.ko ubuntu@10.19.65.176:/tmp/
B. On Linux device console, insert these modules using insmod command.
   insmod /tmp/pwm-tegra.ko
   insmod /tmp/pwm-tegra-tachometer.ko
   insmod /tmp/generic-pwm-tachometer.ko
C. Read RPM value at below sysfs node
   cat /sys/devices/platform/generic_pwm_tachometer/hwmon/hwmon0/rpm
D. Change the FAN speed using PWM sysfs interface. Follow below steps for the same:
   a. cd /sys/class/pwm/pwmchip0
   b. ls -la (make sure pwm controller is c340000.pwm)
      Output should be: device -> ../../../c340000.pwm
   c. echo 0 > export
   d. cd pwmchip0:0
   e. echo 8000 > period
   f. echo 1 > enable
   g. echo 7000 > duty_cycle # change duty_cycles from 0 to 7000 and see FAN speed
   h. cat /sys/devices/platform/generic_pwm_tachometer/hwmon/hwmon0/rpm
   i. echo 4000 > duty_cycle
   h. cat /sys/devices/platform/generic_pwm_tachometer/hwmon/hwmon0/rpm
   i. echo 2000 > duty_cycle
   h. cat /sys/devices/platform/generic_pwm_tachometer/hwmon/hwmon0/rpm
   i. echo 0 > duty_cycle
   h. cat /sys/devices/platform/generic_pwm_tachometer/hwmon/hwmon0/rpm

Rajkumar Rampelli (10):
  pwm: core: Add support for PWM HW driver with pwm capture only
  dt-bindings: Tegra186 tachometer device tree bindings
  pwm: tegra: Add PWM based Tachometer driver
  hwmon: generic-pwm-tachometer: Add DT binding details
  hwmon: generic-pwm-tachometer: Add generic PWM based tachometer
  arm64: tegra: Add Tachometer Controller on Tegra186
  arm64: tegra: Add PWM based Tachometer support on Tegra186
  arm64: defconfig: enable Nvidia Tegra Tachometer as a module
  arm64: defconfig: Enable Generic PWM based Tachometer driver
  arm64: tegra: Add PWM controller on Tegra186 soc

 .../bindings/hwmon/generic-pwm-tachometer.txt      |  25 ++
 .../bindings/pwm/pwm-tegra-tachometer.txt          |  31 +++
 Documentation/hwmon/generic-pwm-tachometer         |  17 ++
 arch/arm64/boot/dts/nvidia/tegra186-p2771-0000.dts |   5 +
 arch/arm64/boot/dts/nvidia/tegra186.dtsi           |  28 ++
 arch/arm64/configs/defconfig                       |   2 +
 drivers/hwmon/Kconfig                              |  10 +
 drivers/hwmon/Makefile                             |   1 +
 drivers/hwmon/generic-pwm-tachometer.c             | 112 ++++++++
 drivers/pwm/Kconfig                                |  10 +
 drivers/pwm/Makefile                               |   1 +
 drivers/pwm/core.c                                 |   4 +
 drivers/pwm/pwm-tegra-tachometer.c                 | 303 +++++++++++++++++++++
 13 files changed, 549 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwmon/generic-pwm-tachometer.txt
 create mode 100644 Documentation/devicetree/bindings/pwm/pwm-tegra-tachometer.txt
 create mode 100644 Documentation/hwmon/generic-pwm-tachometer
 create mode 100644 drivers/hwmon/generic-pwm-tachometer.c
 create mode 100644 drivers/pwm/pwm-tegra-tachometer.c

-- 
2.1.4