From patchwork Fri Mar 22 08:24:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Wahren X-Patchwork-Id: 10865247 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 F316913B5 for ; Fri, 22 Mar 2019 08:25:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D9CA82A362 for ; Fri, 22 Mar 2019 08:25:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CDDF92A3BB; Fri, 22 Mar 2019 08:25:21 +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=ham 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 4C8112A362 for ; Fri, 22 Mar 2019 08:25:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727655AbfCVIZP (ORCPT ); Fri, 22 Mar 2019 04:25:15 -0400 Received: from mout.kundenserver.de ([212.227.126.187]:38649 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726667AbfCVIZK (ORCPT ); Fri, 22 Mar 2019 04:25:10 -0400 Received: from stefan-Vostro-260.fritz.box ([109.104.35.112]) by mrelayeu.kundenserver.de (mreue012 [212.227.15.167]) with ESMTPSA (Nemesis) id 1MmyzH-1ggTMc1sSF-00k9Ob; Fri, 22 Mar 2019 09:24:25 +0100 From: Stefan Wahren To: Kamil Debski , Bartlomiej Zolnierkiewicz , Jean Delvare , Guenter Roeck , Rob Herring , Mark Rutland , Robin Murphy Cc: linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Stefan Wahren Subject: [PATCH V3 3/3] hwmon: pwm-fan: Add RPM support via external interrupt Date: Fri, 22 Mar 2019 09:24:03 +0100 Message-Id: <1553243043-19486-4-git-send-email-stefan.wahren@i2se.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1553243043-19486-1-git-send-email-stefan.wahren@i2se.com> References: <1553243043-19486-1-git-send-email-stefan.wahren@i2se.com> X-Provags-ID: V03:K1:BKJN9Q9q6HffqWUvmt7OCSlaDv3ROlw5ShmcUOhFJduN5DQWANn lsG+fl26E3s3wOpv4O1gIyY3a65kxNtz0iEqACc5w4uYzFW9a4r6c7ooJCEQmh8bHudTabx TMfairwcAsjo3K5lBPHgY+ill+godecZOWtbDabeL19V8gY18tvXlOLfmvB3rytWzUnq22Z 5kbJ1nD+9a9q3LFUDqX6g== X-UI-Out-Filterresults: notjunk:1;V03:K0:vxz82F/+m+0=:9v0eqPthQ4fRMgFfTHo4qo RrQrfjPITyV2BGtZtgxtrbnCOfmZ0WKjhP68S4qt+HVIoi9E5YZKBzHBHBY2TZ7IHsufPf7u4 IUlIYRF23M2BWq63F1yuc/5O4COXylkKn/+3bvwKVqpdto5NW6Cy5cN8xyFT2O7ufIDRZOonp lzzK313KGvkuo8ASIViCQVgrKg3qU3341S6cTImT2YPu9RkYgnubyxncAmXTKhoiesGXZuBP4 MYiG70zBeUnnonu3at0+IUwonpP5vPR32Hh2wOcoE0ewsp/OnuPN9c6tWZlt7jT/7qgYI+DaC h4OvdgITQERXN2lKthiC1wipmDIpB8mDQlaUOmWv7oPihCXYbjWKrZrV4nr+tapJuV6pPGYKU iM3eoKKuyf6a5CYa48vNhcjV4ZrzkW7o2LyGvlc68OZRV3lnhBQaGN+mV6FkU4jmO3bA/rhA3 Lvmqg2S3b1TePDdf/hzAC+UhfQdrrXq1yvU0mOyS5bCiE58pJKkdMBdN7jtBI3hnT1CVpcCOj Ayi3pA12CCbPZHV42xSChDGO9UtlZyg2YMPGhy0mEaZTn/IHDIms5GjnHukjl7mmeHwhod/4C DNVw6BSvMiUSrda9MgOgR/OHiOreU0hhZwz/Pz0EhUoks4HkMLOLnx3fZ6x26/p/FzCpfqmaJ Trx7taELAxgPe9QwCIdNFaL/Vkwq/Sm3DWzgtqDZUmWJtnIQ92V8D7dbBfxbrnk5yt9KCpJb+ GEz9/3HhhqC0qnfuJQLt/X3Iq/lPbOq/B1/F+o6S3IpgkaqyA/LWecrrnS+OvnHFR8/9jci7L /xj78Fu Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This adds RPM support to the pwm-fan driver in order to use with fancontrol/pwmconfig. This feature is intended for fans with a tachometer output signal, which generate a defined number of pulses per revolution. Signed-off-by: Stefan Wahren --- drivers/hwmon/pwm-fan.c | 100 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 99 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c index 167221c..c8fb6a3 100644 --- a/drivers/hwmon/pwm-fan.c +++ b/drivers/hwmon/pwm-fan.c @@ -18,6 +18,7 @@ #include #include +#include #include #include #include @@ -26,6 +27,7 @@ #include #include #include +#include #define MAX_PWM 255 @@ -33,6 +35,14 @@ struct pwm_fan_ctx { struct mutex lock; struct pwm_device *pwm; struct regulator *reg_en; + + int irq; + atomic_t pulses; + unsigned int rpm; + u32 pulses_per_revolution; + ktime_t sample_start; + struct timer_list rpm_timer; + unsigned int pwm_value; unsigned int pwm_fan_state; unsigned int pwm_fan_max_state; @@ -40,6 +50,32 @@ struct pwm_fan_ctx { struct thermal_cooling_device *cdev; }; +/* This handler assumes self resetting edge triggered interrupt. */ +static irqreturn_t pulse_handler(int irq, void *dev_id) +{ + struct pwm_fan_ctx *ctx = dev_id; + + /* Avoid possible overflow */ + if (atomic_read(&ctx->pulses) < 100000) + atomic_inc(&ctx->pulses); + + return IRQ_HANDLED; +} + +static void sample_timer(struct timer_list *t) +{ + struct pwm_fan_ctx *ctx = from_timer(ctx, t, rpm_timer); + int pulses, sample_ms; + + pulses = atomic_read(&ctx->pulses); + atomic_sub(pulses, &ctx->pulses); + sample_ms = ktime_ms_delta(ktime_get(), ctx->sample_start); + ctx->rpm = pulses * 60 * sample_ms / 1000 / ctx->pulses_per_revolution; + + ctx->sample_start = ktime_get(); + mod_timer(&ctx->rpm_timer, jiffies + HZ); +} + static int __set_pwm(struct pwm_fan_ctx *ctx, unsigned long pwm) { unsigned long period; @@ -100,15 +136,49 @@ static ssize_t pwm_show(struct device *dev, struct device_attribute *attr, return sprintf(buf, "%u\n", ctx->pwm_value); } +static ssize_t rpm_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pwm_fan_ctx *ctx = dev_get_drvdata(dev); + + return sprintf(buf, "%u\n", ctx->rpm); +} static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, 0); +static SENSOR_DEVICE_ATTR_RO(fan1_input, rpm, 0); static struct attribute *pwm_fan_attrs[] = { &sensor_dev_attr_pwm1.dev_attr.attr, + &sensor_dev_attr_fan1_input.dev_attr.attr, NULL, }; -ATTRIBUTE_GROUPS(pwm_fan); +static umode_t pwm_fan_attrs_visible(struct kobject *kobj, struct attribute *a, + int n) +{ + struct device *dev = container_of(kobj, struct device, kobj); + struct pwm_fan_ctx *ctx = dev_get_drvdata(dev); + struct device_attribute *devattr; + + /* Hide fan_input in case no interrupt is available */ + devattr = container_of(a, struct device_attribute, attr); + if (devattr == &sensor_dev_attr_fan1_input.dev_attr) { + if (ctx->irq < 0) + return 0; + } + + return a->mode; +} + +static const struct attribute_group pwm_fan_group = { + .attrs = pwm_fan_attrs, + .is_visible = pwm_fan_attrs_visible, +}; + +static const struct attribute_group *pwm_fan_groups[] = { + &pwm_fan_group, + NULL, +}; /* thermal cooling device callbacks */ static int pwm_fan_get_max_state(struct thermal_cooling_device *cdev, @@ -261,6 +331,32 @@ static int pwm_fan_probe(struct platform_device *pdev) goto err_reg_disable; } + timer_setup(&ctx->rpm_timer, sample_timer, 0); + + if (of_property_read_u32(pdev->dev.of_node, "pulses-per-revolution", + &ctx->pulses_per_revolution)) { + ctx->pulses_per_revolution = 2; + } + + if (!ctx->pulses_per_revolution) { + dev_err(&pdev->dev, "pulses-per-revolution can't be zero.\n"); + ret = -EINVAL; + goto err_pwm_disable; + } + + atomic_set(&ctx->pulses, 0); + ctx->irq = platform_get_irq(pdev, 0); + if (ctx->irq >= 0) { + ret = devm_request_irq(&pdev->dev, ctx->irq, pulse_handler, 0, + pdev->name, ctx); + if (ret) { + dev_err(&pdev->dev, "Can't get interrupt working.\n"); + goto err_pwm_disable; + } + ctx->sample_start = ktime_get(); + mod_timer(&ctx->rpm_timer, jiffies + HZ); + } + hwmon = devm_hwmon_device_register_with_groups(&pdev->dev, "pwmfan", ctx, pwm_fan_groups); if (IS_ERR(hwmon)) { @@ -306,6 +402,8 @@ static int pwm_fan_remove(struct platform_device *pdev) struct pwm_fan_ctx *ctx = platform_get_drvdata(pdev); thermal_cooling_device_unregister(ctx->cdev); + del_timer_sync(&ctx->rpm_timer); + if (ctx->pwm_value) pwm_disable(ctx->pwm);