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,USER_AGENT_MUTT autolearn=unavailable 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 E64F3C282DA for ; Thu, 31 Jan 2019 17:56:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB1B520881 for ; Thu, 31 Jan 2019 17:56:56 +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="KRz3UnnQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727701AbfAaR4z (ORCPT ); Thu, 31 Jan 2019 12:56:55 -0500 Received: from mail-pg1-f196.google.com ([209.85.215.196]:39915 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726744AbfAaR4z (ORCPT ); Thu, 31 Jan 2019 12:56:55 -0500 Received: by mail-pg1-f196.google.com with SMTP id r11so1670722pgp.6; Thu, 31 Jan 2019 09:56:54 -0800 (PST) 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=YAFwcmRQ+VrKG4nQJh5Kon4m4cc+l/9DNk+7txAG8QU=; b=KRz3UnnQ6zyjWJezDVsIj6D8UyErHJcHeacVK5bR/wcOYO4M/d6KcnKPEPauUq/Wzr 0G+ZoW2JDqTnt0D1zeEGePDtwXtMB/IQOIWC3v59HNqHmowYRiv2DrY2/GW3H80FtMKs LUY3dZH9OjDwqtFI6XM9oRLCniJTug6s7rhQcS+VGqQr8GLFlkOD7P8aZYxcO4MW5o3G FNyT1aGyF8PDK51J1hqYnMYZI+sPU41RcWM++exmVbQ+qAa1JhKCsDCbheP44xodoayc VN4RQu8XPmx6015maJf7W9ZC0PcLPLpXVlCCc30zXDXn4wzrbF3Ge1jmbMVJ23wVi7ML QvXg== 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=YAFwcmRQ+VrKG4nQJh5Kon4m4cc+l/9DNk+7txAG8QU=; b=goWPwq0mvqEZIE1LrABBwnP+YRJTGKA60aUIG8wuoVEASwcr0bWtFNaayfjlN8DB9R LgEO4MLCIDYAyP0mqpOpmcsWnefd+xhrd6zdOx8ExbW7ISr9wPlrNEhJc7z4b3e3RR1G mPI2U+W9W8Y3IEdTAdDYpvBMCtzG9Wjd8ma1dAcb8NEYLGLxaHPiqlXE5dOcvTNlIbnt UZk2E3vVrckcYPIYmrOzXozIET6av/ArEqkrLNR7hr51a7IjPpYHSsEncGnn+nbjSs4Q rZ+EkGjXCYw4MS0Nvr2v3BpL8n3u6VJqqWyoXCB19U1X9utkExtmwD8aAVLU0RyKEjVU 3smg== X-Gm-Message-State: AJcUukeO9I9xr3xaLgVS99jdADQlJGZwlS3/qdU0IytJ7BS6CEyo2xyA GxTXAXvQkCKO184zW/lhHmU= X-Google-Smtp-Source: ALg8bN4MpUuZQb7MEWMRh+Fy78j94nz96NvQw6TlQO1opesEaAzqe6rUvSIIf3d/6r9NNgpIhP0V0Q== X-Received: by 2002:a63:eb0e:: with SMTP id t14mr32677537pgh.445.1548957413841; Thu, 31 Jan 2019 09:56:53 -0800 (PST) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id 128sm9762852pfu.129.2019.01.31.09.56.52 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 31 Jan 2019 09:56:53 -0800 (PST) Date: Thu, 31 Jan 2019 09:56:52 -0800 From: Guenter Roeck To: Stefan Wahren Cc: Kamil Debski , Bartlomiej Zolnierkiewicz , Jean Delvare , Rob Herring , Mark Rutland , linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] hwmon: pwm-fan: Add optional regulator support Message-ID: <20190131175651.GA16231@roeck-us.net> References: <1548781631-5736-1-git-send-email-stefan.wahren@i2se.com> <1548781631-5736-2-git-send-email-stefan.wahren@i2se.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1548781631-5736-2-git-send-email-stefan.wahren@i2se.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 29, 2019 at 06:07:11PM +0100, Stefan Wahren wrote: > This adds optional regulator support to the pwm-fan driver. This is > necessary for pwm fans which are powered by a switchable supply. > > Signed-off-by: Stefan Wahren > --- > drivers/hwmon/pwm-fan.c | 35 +++++++++++++++++++++++++++++++++++ > 1 file changed, 35 insertions(+) > > diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c > index 2c94482..9e0591e 100644 > --- a/drivers/hwmon/pwm-fan.c > +++ b/drivers/hwmon/pwm-fan.c > @@ -23,6 +23,7 @@ > #include > #include > #include > +#include > #include > #include > > @@ -31,6 +32,7 @@ > struct pwm_fan_ctx { > struct mutex lock; > struct pwm_device *pwm; > + struct regulator *reg_en; > unsigned int pwm_value; > unsigned int pwm_fan_state; > unsigned int pwm_fan_max_state; > @@ -244,6 +246,23 @@ static int pwm_fan_probe(struct platform_device *pdev) > return ret; > } > > + ctx->reg_en = devm_regulator_get_optional(&pdev->dev, "fan"); > + if (!IS_ERR(ctx->reg_en)) { It is customary to handle the error case first. > + ret = regulator_enable(ctx->reg_en); > + if (ret) > + dev_err(&pdev->dev, > + "Failed to enable fan supply: %d\n", ret); > + } else { > + switch (PTR_ERR(ctx->reg_en)) { > + case -ENODEV: > + case -ENOSYS: Does devm_regulator_get_optional() ever return -ENOSYS ? I glanced through other calls to devm_regulator_get_optional(), but I don't see that check anywhere. > + ctx->reg_en = NULL; > + break; > + default: > + return PTR_ERR(ctx->reg_en); > + } This is inconsistent. Provided regulators which fail to enable are accepted, albeit with an error message, while unexpected errors from devm_regulator_get_optional() result in a bailout. Please be consistent. > + } > + > hwmon = devm_hwmon_device_register_with_groups(&pdev->dev, "pwmfan", > ctx, pwm_fan_groups); > if (IS_ERR(hwmon)) { > @@ -287,6 +306,10 @@ static int pwm_fan_remove(struct platform_device *pdev) > thermal_cooling_device_unregister(ctx->cdev); > if (ctx->pwm_value) > pwm_disable(ctx->pwm); > + > + if (ctx->reg_en) > + regulator_disable(ctx->reg_en); As written, this is also called after regulator_enable() failed. Same below. > + > return 0; > } > > @@ -299,6 +322,12 @@ static int pwm_fan_suspend(struct device *dev) > > pwm_get_args(ctx->pwm, &args); > > + if (ctx->reg_en) { > + ret = regulator_disable(ctx->reg_en); > + if (ret) > + dev_err(dev, "Failed to disable fan supply: %d\n", ret); > + } > + > if (ctx->pwm_value) { > ret = pwm_config(ctx->pwm, 0, args.period); > if (ret < 0) > @@ -317,6 +346,12 @@ static int pwm_fan_resume(struct device *dev) > unsigned long duty; > int ret; > > + if (ctx->reg_en) { > + ret = regulator_enable(ctx->reg_en); > + if (ret) > + dev_err(dev, "Failed to enable fan supply: %d\n", ret); > + } > + > if (ctx->pwm_value == 0) > return 0; >