From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6351AC10F13 for ; Thu, 11 Apr 2019 16:57:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E8292075B for ; Thu, 11 Apr 2019 16:57:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tvZH5YZ2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726585AbfDKQ5p (ORCPT ); Thu, 11 Apr 2019 12:57:45 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:46405 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726014AbfDKQ5p (ORCPT ); Thu, 11 Apr 2019 12:57:45 -0400 Received: by mail-pg1-f195.google.com with SMTP id q1so3776323pgv.13; Thu, 11 Apr 2019 09:57:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=sLbpvr4pCQVgOBW6t/kzx0y8nm7WJU2CoD1sex4Tzok=; b=tvZH5YZ2H1KwW923VEeyvzVLLy05LFJBGvH4MmtEOQuYwGtsnyy0nd3dMKGSQJoaqr Ex6aY9TLfgUcXOnlansHwIRCPFiAonhPYSX1JX8nc9FBraRLSK/6QvP+bF4DBwliA1rh KWnQTRVC/BnXAhoDBKZGnbOftJgMJxhfRJpVN4rNwoQgUbvhYywJcbyk/1hlwfvT+kQT YWiR9sg9J8YCQFUtKvwzQuBJ7VTDh5ZS2AJ1jdqksEus6VdnIBgnBidt+Xu+ZcnPyNxm MuMnaxAD5ca2ifmppFAZCtYd6ZPfF9Zh/b92EhfCzADabLgcLYgp/aQxwGDx/GI/+WER ESaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=sLbpvr4pCQVgOBW6t/kzx0y8nm7WJU2CoD1sex4Tzok=; b=BbylQktQifbq5fI8yOBA1R0fgAWEFTafl09qZfQnnsfzmZbTBb2ww7P2XX0NnqK5uq 7TmpfU5WbnueQkXs7d0bhQEar9Dhe4+uYCW4BE5haoubcOPuy/hE5Q1HI/9Jc0PvLOy8 adIFztjLWJ6hNeG7N9H1/ttmHMP2TTVNWfWt9FQpesJPnWY2d0yCzJnH7FDeh5oT5UCw wGuUsxyXlnyZXClPUMotOJLlZLQvkxQEI4HH0B9Kj+NzV3pmZAfOMpNBtAC7Hb9FlMre YSczGwwo0iZZEynVGaYeEInEY3igKABvwEzeMExeyLh0RhokPMlKyOsG81TsQK6Cfovw RdEA== X-Gm-Message-State: APjAAAW7JF9qnjI3r1A9jimUSod6Mq14tVGMsE+WaxQVJ19HzlVdWSZx OsbP5Cz0VyiiyfFa8gWlp7o= X-Google-Smtp-Source: APXvYqzWDoCRdsCUXn7bWovki47potJFZuJKV+psvZ4VcFUGS8WlpSIvMsYoqWRmWBmSpmPO4Pk8+Q== X-Received: by 2002:a65:44cd:: with SMTP id g13mr41312048pgs.258.1555001864342; Thu, 11 Apr 2019 09:57:44 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id l74sm63151339pfi.174.2019.04.11.09.57.42 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 11 Apr 2019 09:57:43 -0700 (PDT) Date: Thu, 11 Apr 2019 09:57:42 -0700 From: Guenter Roeck To: Stefan Wahren Cc: Kamil Debski , Bartlomiej Zolnierkiewicz , Jean Delvare , Rob Herring , Mark Rutland , Robin Murphy , linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V5 3/3] hwmon: pwm-fan: Add RPM support via external interrupt Message-ID: <20190411165742.GA29395@roeck-us.net> References: <1554989411-23666-1-git-send-email-stefan.wahren@i2se.com> <1554989411-23666-4-git-send-email-stefan.wahren@i2se.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1554989411-23666-4-git-send-email-stefan.wahren@i2se.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org On Thu, Apr 11, 2019 at 03:30:11PM +0200, Stefan Wahren wrote: > 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 | 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); Field day for static analyzers - devattr is no longer used. No need to resend. I'll let the series rest for a couple of days and then apply to hwmon-next (after removing devattr) unless there are additional comments. > + 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); > > -- > 2.7.4 >