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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADF1CEE14A3 for ; Wed, 6 Sep 2023 15:00:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242219AbjIFPAG (ORCPT ); Wed, 6 Sep 2023 11:00:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233482AbjIFPAF (ORCPT ); Wed, 6 Sep 2023 11:00:05 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE98BE49; Wed, 6 Sep 2023 08:00:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1694012401; x=1725548401; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=K0zzGgMQikPv3yIIAmBS05foEO0ENZKMi/sYapbhWsQ=; b=IzbPYnC2DOZt+bINe1PiqicwDBdu8siLzLBD1VdjN3XouSZESZT/rUuk lAjUY7bt5eTjms0aoBuwYmvCvpvYj8z/L/Y0aeAW0HytuTcZfL7YcVTN2 Eo0TXrZtzSkpvxhZ+zSz12GYd8v/8W7lIEp5jO6P6nGGqE7Gmk8ii5lMo Sl/4YbrNuCvU8ssJh+Au8XUtR9YlDm+PYHVPHvmT8uAdgZrb9oiAeasH3 unmkXgXE+RBuZCa1yzH88M8TcH4OcU9UtS7OPRikaGgobWdh6LsLDyUFI C212Cbu13Ju5aMJJuVelYVXq362to/CpL+ClY1mfvyFZ+ol5dTo/3mbi0 A==; X-IronPort-AV: E=McAfee;i="6600,9927,10825"; a="367312076" X-IronPort-AV: E=Sophos;i="6.02,232,1688454000"; d="scan'208";a="367312076" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Sep 2023 08:00:01 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10825"; a="1072412683" X-IronPort-AV: E=Sophos;i="6.02,232,1688454000"; d="scan'208";a="1072412683" Received: from smile.fi.intel.com ([10.237.72.54]) by fmsmga005.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Sep 2023 07:59:58 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.96) (envelope-from ) id 1qdu0Z-006yBd-36; Wed, 06 Sep 2023 17:59:55 +0300 Date: Wed, 6 Sep 2023 17:59:55 +0300 From: Andy Shevchenko To: Biju Das Cc: Eric Tremblay , Jean Delvare , Guenter Roeck , "linux-hwmon@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Biju Das Subject: Re: [PATCH v4 1/2] hwmon: tmp513: Add max_channels variable to struct tmp51x_data Message-ID: References: <20230905184252.222742-1-biju.das.jz@bp.renesas.com> <20230905184252.222742-2-biju.das.jz@bp.renesas.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 06, 2023 at 02:46:37PM +0000, Biju Das wrote: > > On Tue, Sep 05, 2023 at 07:42:51PM +0100, Biju Das wrote: ... > > > +#define TMP51X_TEMP_CONFIG_CONV_RATE FIELD_PREP(GENMASK(9, 7), 0x7) > > > +#define TMP51X_TEMP_CONFIG_RC BIT(10) > > > +#define TMP51X_TEMP_CHANNEL_MASK(n) FIELD_PREP(GENMASK(14, 11), \ > > > + GENMASK((n) - 1, 0)) > > > > Why do you need FIELD_PREP() for the pure constants here? Why can you > > simply define the constants in the proper place? > > I think one can clearly understand the bit definitions and value from FIELD_PREP. I think it is clear over engineering. In the first one the constant can't be more than the field, in the second the defensive programming that is discouraged in the kernel. #define TMP51X_TEMP_CHANNEL_MASK(n) (GENMASK((n) - 1, 0) << 11) would suffice and much easier to understand. ... > > > +#define TMP51X_TEMP_CONFIG_DEFAULT(n) (TMP51X_TEMP_CONFIG_CONT | \ > > > + TMP51X_TEMP_CHANNEL_MASK(n) | \ > > > + TMP51X_TEMP_CONFIG_CONV_RATE | TMP51X_TEMP_CONFIG_RC) > > > > This is better to read in a form of > > > > #define TMP51X_TEMP_CONFIG_DEFAULT(n) \ > > (TMP51X_TEMP_CHANNEL_MASK(n) | TMP51X_TEMP_CONFIG_CONT | \ > > TMP51X_TEMP_CONFIG_CONV_RATE | TMP51X_TEMP_CONFIG_RC) > > > > I just used the indentation suggested by Guenter. But wouldn't my proposal be sightly better to read? -- With Best Regards, Andy Shevchenko