From patchwork Thu Apr 11 13:30:11 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Wahren X-Patchwork-Id: 10896025 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 2BEB314DB for ; Thu, 11 Apr 2019 13:31:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 106E828D7B for ; Thu, 11 Apr 2019 13:31:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0B97728D9B; Thu, 11 Apr 2019 13:31:14 +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 A80CF28D88 for ; Thu, 11 Apr 2019 13:31:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726564AbfDKNbL (ORCPT ); Thu, 11 Apr 2019 09:31:11 -0400 Received: from mout.kundenserver.de ([217.72.192.75]:45259 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726517AbfDKNbL (ORCPT ); Thu, 11 Apr 2019 09:31:11 -0400 Received: from stefan-Vostro-260.fritz.box ([109.104.50.113]) by mrelayeu.kundenserver.de (mreue108 [212.227.15.183]) with ESMTPSA (Nemesis) id 1MOzGc-1hXEgx1nRM-00PMLZ; Thu, 11 Apr 2019 15:30:35 +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 V5 3/3] hwmon: pwm-fan: Add RPM support via external interrupt Date: Thu, 11 Apr 2019 15:30:11 +0200 Message-Id: <1554989411-23666-4-git-send-email-stefan.wahren@i2se.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1554989411-23666-1-git-send-email-stefan.wahren@i2se.com> References: <1554989411-23666-1-git-send-email-stefan.wahren@i2se.com> X-Provags-ID: V03:K1:+NQLgQJ54t9ODRaPDK/OQHkYPntOime3xNIlQyZk0Ruqv8OxguL JwzCwA5g09v7VO2h/kk48vhyJzxgKp5zmd6JEd9PNeQW6z6dUEZGLWNQV0nVYACgyWjLGki RdEDsm0Z19pr21/tC0lw8fdpKbtuoFOsS8auQjT1oKLInOvpyFSyCKbJdPqtIx0FUw2gD58 G9EhuQyg/PyREcj6D8Chg== X-UI-Out-Filterresults: notjunk:1;V03:K0:6p7NAjDJ4Bo=:5kUccsYN5PcLs98AoIX/Zo c/mo54ZdxCDmpMm72B0k961nVCLafWybCbUWkQu7B8RdH7Ty04JMhPUKrs9sQYqzwSLhi7G2g PcJfmeYcihrSffEaysDP/pDs+fG9xyWo31/WptITy2DrU7raTCERNlAh723IC0yX1DgBWE5Wi AMiwGpMUKzysnIrdHUvQegBu1aNVuwE76KH+TuogSkZd/6lt22A9VPUUe38fcFxupaSpSaML6 2BEuz1lNIC8ZO+hKhqQHF4WJPB+qXpdPDgmbuZrY4m4pqgOmuQSQ64K8xdQY+PrsdorSxZtSW kHK1wR/4aXq41tvnjiuwXU/vaTC1kGUrt20+qv8QQRz9XSv+3ZN3/0jYd32QezObMegSmulWL ZAFz6eQvnBxK5AjRMBazTFfODjKQSeiTMJIYgMnORf7bNSu5YiT81iU4jnWxux6sTkRF8H58A uJRjwgSZ3ms2uf25p6wXjVKGQ288gF5uKlxAF6fJ1blZnkhGe4hUyH2wMXUxpK8zblC585Ssc kW1HzFlKy2ju0zF1MlgqyMe4IX3B7pE5YP2wSZSR0EOGe9HsBarJZ8azJdQql6El9TYLfn6Sx 9ybjhS5lAeJzJ9hZo4KDxhyGG3s0rxI5MLV3tu3Ra6LJxXFV8gwIVzN8TNHP3aeALgzO9ZokK eBgHsAo0ycTadjZ2IsIIYqZgmsmhiGoV0wqGNpqjjxFVT2UgSmW5+zSLZi+iCxW+za9VVarqn kRSTbUWcK87Ual47iXbjNyLM0oGkDSzKSAHJeKw09zCucIGMvZbXzgvilAo= 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 Reviewed-by: Robin Murphy Signed-off-by: Robin Murphy --- drivers/hwmon/pwm-fan.c | 107 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 103 insertions(+), 4 deletions(-) diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c index e4c5197..8c4c5ee 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 +136,47 @@ 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 (n == 1 && 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, @@ -214,6 +282,7 @@ static int pwm_fan_probe(struct platform_device *pdev) struct device *hwmon; int ret; struct pwm_state state = { }; + u32 ppr = 2; ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); if (!ctx) @@ -233,6 +302,10 @@ static int pwm_fan_probe(struct platform_device *pdev) platform_set_drvdata(pdev, ctx); + ctx->irq = platform_get_irq(pdev, 0); + if (ctx->irq == -EPROBE_DEFER) + return ctx->irq; + ctx->reg_en = devm_regulator_get_optional(&pdev->dev, "fan"); if (IS_ERR(ctx->reg_en)) { if (PTR_ERR(ctx->reg_en) != -ENODEV) @@ -261,17 +334,38 @@ static int pwm_fan_probe(struct platform_device *pdev) goto err_reg_disable; } + timer_setup(&ctx->rpm_timer, sample_timer, 0); + + of_property_read_u32(pdev->dev.of_node, "pulses-per-revolution", &ppr); + ctx->pulses_per_revolution = ppr; + if (!ctx->pulses_per_revolution) { + dev_err(&pdev->dev, "pulses-per-revolution can't be zero.\n"); + ret = -EINVAL; + goto err_pwm_disable; + } + + 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) - goto err_pwm_disable; + goto err_del_timer; ctx->pwm_fan_state = ctx->pwm_fan_max_state; if (IS_ENABLED(CONFIG_THERMAL)) { @@ -282,7 +376,7 @@ 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 +384,9 @@ 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 +403,8 @@ 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);