From patchwork Tue Apr 2 14:21:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Wahren X-Patchwork-Id: 10881807 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 86A5B922 for ; Tue, 2 Apr 2019 14:22:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6C42328856 for ; Tue, 2 Apr 2019 14:22:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 605FD28866; Tue, 2 Apr 2019 14:22:56 +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 B2C862885E for ; Tue, 2 Apr 2019 14:22:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731217AbfDBOWu (ORCPT ); Tue, 2 Apr 2019 10:22:50 -0400 Received: from mout.kundenserver.de ([212.227.17.24]:49047 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730527AbfDBOWt (ORCPT ); Tue, 2 Apr 2019 10:22:49 -0400 Received: from stefan-Vostro-260.fritz.box ([109.104.50.84]) by mrelayeu.kundenserver.de (mreue107 [212.227.15.183]) with ESMTPSA (Nemesis) id 1N1xZX-1gmtju0Z1V-012Dys; Tue, 02 Apr 2019 16:22:11 +0200 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 V4 3/3] hwmon: pwm-fan: Add RPM support via external interrupt Date: Tue, 2 Apr 2019 16:21:50 +0200 Message-Id: <1554214910-29925-4-git-send-email-stefan.wahren@i2se.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1554214910-29925-1-git-send-email-stefan.wahren@i2se.com> References: <1554214910-29925-1-git-send-email-stefan.wahren@i2se.com> X-Provags-ID: V03:K1:VVbw+itIWBHwSALd3cnJxz+j1kMPQ1KtlkiVX2ngLCHVNzm5q5j 8pgMtrE8qh9Hcw6Jum9IRCVpxbI/8z7A1949GY1g4DEn4epFlOBz4zisMd6A+P3SQZK77Db l6PxO+YVbK3zaCiSqs2E9Jd0lmLjQKMjVX2LEUJUeKz97oPDJvNi0oUML/IG9dMRChbjlk1 WtVjf6DxXMETZuuQVNTkw== X-UI-Out-Filterresults: notjunk:1;V03:K0:oCUxK+9fLXI=:UNk6Sm8jCMNhgsTrIwGnmL F7LxPpAwUOODoZWWjcPPJI7kkfONgWevsj1RI6s0v+Zj2UccjVbX+L2R3/9Xwo0hREXnHqr1w Y0Aqpx9TxxmwgkkH/fy3yX/3IQU2ZuyGD4z6Z6GQde3ZK8MhTp4Yt2r1MewYQSEJcP5SwRBYi ykFv6v9wjdKk6pw/nN8hUEFsxTAPESeDYnCXrcqPRoEo/vpLqhko3d64BnoMEDakCVQ9ReZXi 9iJ4K6cvKWHx10B4+Er6nNkdKQb7Q/t0RFLCW/1sjUmrDacMHyh7XqXMMwU00o7tx4HbZnkQm ok+LPxuc0hxFYsb/SvSxuqMxS+5DbCUSs9ghS95SHyHscsiirXs2dpasCjWk2HNHFENAHDDM2 Q0aJL60cf55W/hGhbUV0ffiXplFiQNUac1kep1h338c7ENAxNs9C0tzDP/kS65tJxOGVTFa2c 0yAKOTrUCh8Fj1bxpqlnLZQhWm82yd6WzCVcm4nmKGwqlOIo9fi1Mv46ZliyUbV4T78wPPN+7 RBV11YVZKzt4DL05PsoZ+IpnD8AtJN7sQt/VKX/MHf4lw+rwbnnsM1XB7GRhxw4NYmBNOVjL5 lr+M+z8RYzlEapAb99IOGJ7bpSt+tOogDKvjkdCwMGfuTmQdoeLBftAjlzvvrXJKZp67XW3jN YNji9cffipvSVMzIxFswua3PnJ0QD4vyeIJ5c0shht957JCDFphiI8vvN76SH9KAPTcS33mYT OchrFPXRi4EYvDxVhZE1+ihyP8WLpmw3rPCzww3B5evX5o7Pm5dTyewKQjQ= 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 | 111 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 107 insertions(+), 4 deletions(-) diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c index 167221c..3245a49 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; + u8 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; + + 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; + u64 tmp; + + pulses = atomic_read(&ctx->pulses); + atomic_sub(pulses, &ctx->pulses); + tmp = (u64)pulses * ktime_ms_delta(ktime_get(), ctx->sample_start) * 60; + do_div(tmp, ctx->pulses_per_revolution * 1000); + ctx->rpm = tmp; + + 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, @@ -261,17 +331,45 @@ 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_u8(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; + } + + ctx->irq = platform_get_irq(pdev, 0); + if (ctx->irq == -EPROBE_DEFER) { + ret = ctx->irq; + goto err_pwm_disable; + } else 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)) { dev_err(&pdev->dev, "Failed to register hwmon device\n"); ret = PTR_ERR(hwmon); - goto err_pwm_disable; + goto err_del_timer; } ret = pwm_fan_of_get_cooling_data(&pdev->dev, ctx); if (ret) - return ret; + goto err_del_timer; ctx->pwm_fan_state = ctx->pwm_fan_max_state; if (IS_ENABLED(CONFIG_THERMAL)) { @@ -282,7 +380,7 @@ static int pwm_fan_probe(struct platform_device *pdev) dev_err(&pdev->dev, "Failed to register pwm-fan as cooling device"); ret = PTR_ERR(cdev); - goto err_pwm_disable; + goto err_del_timer; } ctx->cdev = cdev; thermal_cdev_update(cdev); @@ -290,6 +388,9 @@ static int pwm_fan_probe(struct platform_device *pdev) return 0; +err_del_timer: + del_timer_sync(&ctx->rpm_timer); + err_pwm_disable: state.enabled = false; pwm_apply_state(ctx->pwm, &state); @@ -306,6 +407,8 @@ 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);