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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 49800C47088 for ; Wed, 26 May 2021 15:40:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2AA12613D3 for ; Wed, 26 May 2021 15:40:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233675AbhEZPmR (ORCPT ); Wed, 26 May 2021 11:42:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49876 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233819AbhEZPmM (ORCPT ); Wed, 26 May 2021 11:42:12 -0400 Received: from mail-ot1-x331.google.com (mail-ot1-x331.google.com [IPv6:2607:f8b0:4864:20::331]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6DB5EC061756 for ; Wed, 26 May 2021 08:40:39 -0700 (PDT) Received: by mail-ot1-x331.google.com with SMTP id 69-20020a9d0a4b0000b02902ed42f141e1so1408861otg.2 for ; Wed, 26 May 2021 08:40:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=pPQLkKkMQ3uWimuyAs10pPH0N/fVipRIkvuWmS5PZNU=; b=vWm1J/OQzHg0y2KCs2geYQ+ZLnvjbuqWr1HXg0wGpH7l2eY4ro6VTluvYGdr2iBmQR QHTriiBejbfpHTuzFquuCuOPc6yQnmykc7DgjQ41/i+Z9+cptyp+aIeNu1B18yaJmnzd 7FG0IoSovzTMo6SgkAd+XVPFs/NoveHPqL0cCoHTD1J2e2k2/S8EJ2hYlL8msFK8b0R8 InBpsmSwulQNPUMCW+4W+03QUTKwr29ERvXonrnvFPhSxWYzJUHt2HB/00ZOEVZr0G9g 8UCpmfR62WMMwE1G5njRssTeDxVxraMS6H0m1PLVg/4UTjqUo8FGn1KTMYwXlHyK9KOi zJqw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=pPQLkKkMQ3uWimuyAs10pPH0N/fVipRIkvuWmS5PZNU=; b=LllWcxBx5wbTUYPOWzWunEVB9Q+VJLQChHQ7w+AWFDscc0YjuuGRKGOyl9LLGiwqkn PbPIJz6V2IDsFBGqtauN99zR7BQ3lNmrhAD7uBksNDCR6WnLsFwO3uWktzc0OS/stB1v RsatMYRMiamcK4f+j6yCREY5TWOr7QA1Ksi0oiG/xjXfZpCnO2bV0siw75vQgHuBuRGb 0vrlUM7Ag9h0I1Anw+4XafWyG2dqtI5S9rzs6XHSADTw6aHttjsX4aKaN4X/sBh22NVk g7fCl4cIPHioDlJhkcqVMvzKTLcB01dHIUoGd9/9jCEIZt9NZnxQYGJTJEuhIRMIOFPQ c8bg== X-Gm-Message-State: AOAM533io4VOg1u7tgwu2XbxU/tJ6X4a1tiHS1swsseoiFVOZSEzcEDU jbzH8u+xZ3TdQNAG997JwT+idWCzU0s= X-Google-Smtp-Source: ABdhPJwqYOpi7cR7vCz+gj7gSqbUvhmUojpu/TcXhg+Y8PgzPmXeLmX8vRvGfulRskDkq5DKW3Js6A== X-Received: by 2002:a05:6830:4da:: with SMTP id s26mr2857587otd.77.1622043638533; Wed, 26 May 2021 08:40:38 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id x11sm4488944otr.36.2021.05.26.08.40.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 May 2021 08:40:38 -0700 (PDT) Sender: Guenter Roeck From: Guenter Roeck To: linux-hwmon@vger.kernel.org Cc: Jean Delvare , jan.kundrat@cesnet.cz, kubernat@cesnet.cz, Guenter Roeck Subject: [PATCH 6/7] hwmon: (max31790) Detect and report zero fan speed Date: Wed, 26 May 2021 08:40:21 -0700 Message-Id: <20210526154022.3223012-7-linux@roeck-us.net> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210526154022.3223012-1-linux@roeck-us.net> References: <20210526154022.3223012-1-linux@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org If a fan is not running or not connected, of if fan monitoring is disabled, the fan count register returns a fixed value of 0xffe0. So far this is then translated to a RPM value larger than 0. Since this is misleading and does not really make much sense, report a fan RPM of 0 in this situation. Cc: Jan Kundrát Cc: Václav Kubernát Signed-off-by: Guenter Roeck --- drivers/hwmon/max31790.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/max31790.c b/drivers/hwmon/max31790.c index 8e4fd9b7c889..91fe419b596c 100644 --- a/drivers/hwmon/max31790.c +++ b/drivers/hwmon/max31790.c @@ -40,6 +40,8 @@ #define FAN_RPM_MIN 120 #define FAN_RPM_MAX 7864320 +#define FAN_COUNT_REG_MAX 0xffe0 + #define RPM_FROM_REG(reg, sr) (((reg) >> 4) ? \ ((60 * (sr) * 8192) / ((reg) >> 4)) : \ FAN_RPM_MAX) @@ -175,7 +177,10 @@ static int max31790_read_fan(struct device *dev, u32 attr, int channel, return 0; case hwmon_fan_input: sr = get_tach_period(data->fan_dynamics[channel % NR_CHANNEL]); - rpm = RPM_FROM_REG(data->tach[channel], sr); + if (data->tach[channel] == FAN_COUNT_REG_MAX) + rpm = 0; + else + rpm = RPM_FROM_REG(data->tach[channel], sr); *val = rpm; return 0; case hwmon_fan_target: -- 2.25.1