From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9DFEF3FBB5E; Sat, 3 Oct 2026 15:24:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.21 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791041083; cv=none; b=HZ6Olx41Ntn/bi6H4EYZrAkfywLB0efuiSXHziGnQDuUC56bnU33QNLEv2qSwzPhxeSmTMv5By6+xiT+afizAbvTgyHwI+RFQTfbSwblnzrrXcw8VmMAZjsWsleWNGkO++WXvqN9HnZRRfx6O9mg+cwmG7OREWkfyENupAmCow8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791041083; c=relaxed/simple; bh=XL12iT3BbGxqZklS+zqkfyINVyUhD9hlO7xgKM4eW64=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=awECBNFVxTyrjgIAO5YtUB3eejxKClyandmissZ/bj9f5STTx7wsJ5M/n0S4JlZJaukWFg0bOZta51oSbtX8ittJq50l/JZpUcIgGrr0y+2eC9b6eWBB48qFpURS/iLKjDqmnpb7oYnQr5FaVRNvQtDQQvhaNmZqlryIx9p0BbY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=lOMLIEFQ; arc=none smtp.client-ip=198.175.65.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="lOMLIEFQ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1791041082; x=1822577082; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=XL12iT3BbGxqZklS+zqkfyINVyUhD9hlO7xgKM4eW64=; b=lOMLIEFQ89l8QFvD+08FKDEacx8Xyq69b8UWnfLXD+hwHVvg/V0vlXNX +SmgA16CU1ur5Dq1G630Wti2ZyTM6wxpGspDua6yCyxff1Vq/l9wkyoby OE0qDTcUdSxzH9LGtJhFQ5VefN4+Fp0id2wGU1fQaR863KclT1hcK8OZT +YvRG6og6asx8EEpOY2hA5KdJoL9eH78+14I9TWdGYC79AkwwanNXFoay 52yxYkg6BbUQVIcTYxlgpEx2bFqRmiz2/QWTdjQkhsK93Di5IhIAZmn8p aKTJXgBRopgaR3nZ/zb/56Hevr1xDnNUGTcvly+uCceW3tcl+/FoibRiH w==; X-CSE-ConnectionGUID: e9c0YfvlQVW42XemUwS3cg== X-CSE-MsgGUID: x8H7KT88QPOJw8CV15P+SA== X-IronPort-AV: E=McAfee;i="6800,10657,11924"; a="90635771" X-IronPort-AV: E=Sophos;i="6.27,138,1787036400"; d="scan'208";a="90635771" Received: from fmviesa013.fm.intel.com ([10.60.135.153]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Oct 2026 08:24:42 -0700 X-CSE-ConnectionGUID: q06nRWtqQgSqFtjevDdxeQ== X-CSE-MsgGUID: /LccEnsMQVeI99Jis/b+zQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,138,1787036400"; d="scan'208";a="448478" Received: from amilburn-desk.amilburn-desk (HELO localhost) ([10.245.245.78]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Oct 2026 08:24:38 -0700 Date: Sat, 3 Oct 2026 18:24:36 +0300 From: Andy Shevchenko To: Sakari Ailus Cc: Maurizio Casciano , mchehab@kernel.org, linux-media@vger.kernel.org, bingbu.cao@amd.com, jacopo.mondi@ideasonboard.com, nicholas@rothemail.net, andy@kernel.org, hansg@kernel.org, gregkh@linuxfoundation.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 02/16] media: ov8858: support 19.2 MHz clock and CHT gain setup Message-ID: References: <628adb1cabec866554ca26a2da5af860b04d6cb1.1788360629.git.mauriziocasciano7@gmail.com> 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: Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo On Fri, Oct 02, 2026 at 10:13:09PM +0300, Sakari Ailus wrote: > On Fri, Oct 02, 2026 at 10:14:29AM +0300, Andy Shevchenko wrote: ... > > > > +#define OV8858_LINK_FREQ (360 * HZ_PER_MHZ) > > > > +#define OV8858_XVCLK_FREQ_24MHZ 24000000 > > > > +#define OV8858_XVCLK_FREQ_19_2MHZ 19200000 > > > > > > Why to use HZ_PER_MHZ for LINK_FREQ but not the rest? > > > > Because we do not do floats in the kernel. And hence for the consistency's > > sake. > > Floating point operations won't end up in generated code even if you have > floating point numbers here -- it's an integer constant. Theoretically there is a room of misinterpretation, not every float number can be represented as finite binary sequence, meaning that it might be off-by-one or higher magnitude of difference in the desired and compiled values. So it is better to avoid floats even on compile-time. -- With Best Regards, Andy Shevchenko