From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f174.google.com (mail-pl1-f174.google.com [209.85.214.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F338E7FBBA; Mon, 6 May 2024 13:49:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715003379; cv=none; b=E2RytTaEarcHL+KxYE3RkZTU6JVAnIFD0AeCNItG1zSrUdnSk2plgXaLsMFer6/iHTX3gy//5FBXkgwYDthx0PhoRH41zNY6l2igJJuwOu7rUP3ZJvfW8srzNAi2Ly9oIcE9c7dyTSl1oDWiG7NCTMe+6hvSmt4CB24KG4uAdOY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715003379; c=relaxed/simple; bh=VeYTlSC5e0onakW3rKrio1y3PTvEXFB4w3FqeXv54R0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KFouI721ubmmpedz01E0x1SjdMw/dRl864KO6FSUk+y6HgjNU+3wKYORoQauJitgCdKmq00b+PrtLSGAZ70Vu6VpuwbtnwLOjgw5yrXkFNWd599ZK5okR/N+MY7qPSflIIwBSrhNydDozeMuGD1HqVQi4eENqEsE5PGYK0lQSMs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=roeck-us.net; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=R1QhkbCi; arc=none smtp.client-ip=209.85.214.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=roeck-us.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="R1QhkbCi" Received: by mail-pl1-f174.google.com with SMTP id d9443c01a7336-1eb24e3a2d9so18820455ad.1; Mon, 06 May 2024 06:49:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1715003377; x=1715608177; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=Q0tf2qu9Q8Di2qMp5UR/PKhNSbAhcOms4Eni4j4Wu/o=; b=R1QhkbCi0fc3Xjz8OP1ckLFlW/5xarey+CHz41prrImsxYQOuKcX8dlbM0RMhXJEaV pdrn8O1+ue732K/HAWqd0z00pjxwSUOVKG0OzZgJgaFCLRXI+G5ybPU3I5LN/MpeEkut W+qXokBrVHrmTHCSKmFUbZka8nFkduyL8xHg0+9S4+1W6PQKJJpMDmy/q/GZqjbbddY0 8S7ba1c8QAyTu0V5+dA76PR3UxzitwkgublPHgAPrW2i8Q1S6JAGXJWZ6rUyBDj5AHbq PoYQFsnzsUSIZF3ChnGdPsEGgsQvQIt6+lG8Yv01aZprJiqaL9gSWRDPoVBtMejytM8G zAzw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1715003377; x=1715608177; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Q0tf2qu9Q8Di2qMp5UR/PKhNSbAhcOms4Eni4j4Wu/o=; b=j5Fi98VmcdOqWd+9qqYcN9TFILuzADoy+J7KlURD21bTl/8wh/g7qSIykN4Ongq5YW mtVirn+PT3fel2y4Bm0JPg60td9bC+Z/PGZyLmri7gYDecDjjcKiOVGqqbhVHu9hKtln hjkFg+qk8/78+z428eZTQVxWxDHCfaUN8uuzqe4oSVupCl8fn2ibsYCDkHGBsIswjhIV +CMHQ8f31Gg/hlsXuGo6o8dfaeR5lB5c44leHu1w7g6wOffdVFb+UHzuRZiqN/UsN7rc H6oCYnDjNsxEHcFlMgsgoExnGLdiHzD+r4GiIidO6mNF70UJTdd51I6t72C4/+oNLLA+ BWtg== X-Forwarded-Encrypted: i=1; AJvYcCV7JcixGPi31J9JQ9v1A96KCn4SFx5j0fPXwfXALX8fmd5Akj3pER8+i7HJq+17AJzCJQeVKz0EK06/UIDbM8K8Nvn8cEks8n1Q0c2nkR1EIywdBRR03eQm+m/ASoR5cG3TjblYlAnlpSKstwR10Uy/o616SqfrsTPhu/G5gPuV7pFqQak= X-Gm-Message-State: AOJu0Yw1LgbxfUsZCA6LOtMB8mWuiok85Worr75N1IfT/G4dLPFESNfa BOoYb1STKhTVC2jIUnVICIsCQqUki5eyNai8y2UQvi/9fwqU5/kd X-Google-Smtp-Source: AGHT+IFsSZGL2it7t9nrfAcHqKBBtNdyFp8UV64K//be7jHkwT4m1n655IsAPNPg10zU+pm1Y4qQLQ== X-Received: by 2002:a17:902:e947:b0:1e2:8841:8d67 with SMTP id b7-20020a170902e94700b001e288418d67mr14383470pll.32.1715003376608; Mon, 06 May 2024 06:49:36 -0700 (PDT) Received: from server.roeck-us.net ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id w13-20020a170902d3cd00b001ec460b50casm8290294plb.307.2024.05.06.06.49.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 May 2024 06:49:35 -0700 (PDT) Sender: Guenter Roeck Date: Mon, 6 May 2024 06:49:34 -0700 From: Guenter Roeck To: Naresh Solanki Cc: Rob Herring , krzysztof.kozlowski+dt@linaro.org, u.kleine-koenig@pengutronix.de, Jean Delvare , linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org Subject: Re: [PATCH 2/4] hwmon: (max6639) : Utilise pwm subsystem Message-ID: <6d424919-70cc-43dc-a5a0-eab24f42f9e8@roeck-us.net> References: <20240416171720.2875916-1-naresh.solanki@9elements.com> <20240416171720.2875916-2-naresh.solanki@9elements.com> <1294114a-4509-4c8a-a0a2-39f6e5f83227@roeck-us.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Mon, May 06, 2024 at 03:35:40PM +0530, Naresh Solanki wrote: > +Rob Herring > > Hi Guenter, > > > On Mon, 22 Apr 2024 at 18:07, Guenter Roeck wrote: > > > > On 4/22/24 03:39, Naresh Solanki wrote: > > > Hi Guenter, > > > > > > On Wed, 17 Apr 2024 at 02:52, Guenter Roeck wrote: > > >> > > >> On Tue, Apr 16, 2024 at 10:47:15PM +0530, Naresh Solanki wrote: > > >>> Utilise pwm subsystem for fan pwm handling > > >>> > > >>> Signed-off-by: Naresh Solanki > > >> > > >> That adds a lot of complexity to the driver. I am missing the benefits. > > >> You are supposed to explain why you are making changes, not just that > > >> you are making them. > > >> > > >> Why are you making those changes ? > > > Sure. > > > This is to align with fan-common.yml wherein chip pwm is exposed. > > > I'll update commit message > > > > > > > Adding lots of complexity to a driver just to have it match a yaml file ? > > I'll want to see a use case. Explain why you need the pwm exposed. > > "because the yaml file demands it" is not a use case. > The idea behind this was that this approach provides flexibility with > hardware routing i.e., PWM0 might be connected to Fan1 & vise > versa instead of assuming 1:1 mapping. > The chip does not support such a configuration. Any hardware implementing this would make automatic fan control using the chip's capabilities impossible. Also, userspace fan control does not rely on the pwm subsystem. This would make sense if someone was to use the chip as generic pwm controller, which would be very unlikely. A "might be" is not sufficient to warrant such an invasive and (in terms of code size) expensive change. Thanks, Guenter