From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) (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 5615F31354C; Thu, 15 Jan 2026 08:47:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.9 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768466839; cv=none; b=JOwNP4Jw+wvlAr3jOUULYx5aI0U8m8vjpi9Ozp6TfFyNfIPPdyP1u1MxzXcA1PPwd5Vaf1drLPDRwzQ/smmrsyeiBxQhnkMhpCx+G7y88+2FbWjugE7GPEdwKFq0DNpePI6frNZsKczGYwf8odMZJLhY+oL2BCMW68/103No9Eg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768466839; c=relaxed/simple; bh=VB3s4Vtnia94BYmzH5RpaIiyd/44mzLETLVflJuTnek=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rZ6DAoD6OoP8vH0CMsIrlLTMRKwt8y57ic79DbV4BZ7J31c3KNW9fRDpov29GQYzAYLUyQPSH8ymC0P+uXQcsCrO+Z+go9kKZbmt1Jl0avEoJ0L0c+reEWMjaGup442trhzPDa9MGMJffcQQMFPu7pD27RU/CItF4JwjHY7yXLE= 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=jWwB+Uce; arc=none smtp.client-ip=198.175.65.9 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="jWwB+Uce" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1768466837; x=1800002837; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=VB3s4Vtnia94BYmzH5RpaIiyd/44mzLETLVflJuTnek=; b=jWwB+UceVnl73wW+L2B6M50LSfkmoExxOYL9pwkNHfGKj0G+Ug7MENSm CcIlkqw8+BsIY8c5Jzb5czgZJ7BEhA792fJK83kHuTGyotHlNUHuG481j GrlBvIFZBQW8+azHCAy/Wr6hZ3NrCtIHFfJodJF+A/g7wSPdE0epHqpSY HzQJQ7/n7kdkDKxa2JUHauSSkmIihJ0uEN8qdPZHQQ0v7G3+uwW566IvG GFLAO5FWWZwlTa/RFEkHhm79l4KyOXs7iqeXj4C83EdMHDTMQnDpH9NLD xRkXxREpIyCujZOgVtUv5hviDJ/C23nmm+xQcb88N8Wt6nw03dc5TlCuQ Q==; X-CSE-ConnectionGUID: t+EV4yUNSxKI2z6jEBZyQg== X-CSE-MsgGUID: 0rqcoQCCSUGKowC5nOPJ4A== X-IronPort-AV: E=McAfee;i="6800,10657,11671"; a="92439706" X-IronPort-AV: E=Sophos;i="6.21,226,1763452800"; d="scan'208";a="92439706" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jan 2026 00:47:16 -0800 X-CSE-ConnectionGUID: FPdCwKzhQaKIGTXzzgfHew== X-CSE-MsgGUID: t4H+Il3eRNCelmQ6mJETmA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,226,1763452800"; d="scan'208";a="204111066" Received: from egrumbac-mobl6.ger.corp.intel.com (HELO localhost) ([10.245.244.216]) by orviesa010-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jan 2026 00:47:15 -0800 Date: Thu, 15 Jan 2026 10:47:12 +0200 From: Andy Shevchenko To: WooYoung Jeon Cc: Andy Shevchenko , Greg Kroah-Hartman , dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] staging: fbtft: replace udelay with usleep_range Message-ID: References: <20260115084019.28574-1-chococookieman1@gmail.com> Precedence: bulk X-Mailing-List: linux-fbdev@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: <20260115084019.28574-1-chococookieman1@gmail.com> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo On Thu, Jan 15, 2026 at 05:40:19PM +0900, WooYoung Jeon wrote: > In the fb_ra8875 driver, udelay(100) is used for delay which > causes busy-waiting. Replacing it with usleep_range(100, 120) > allows the CPU to sleep during the delay, improving system > resource efficiency. > > This change was suggested by checkpatch.pl. Without HW test it's no go. See the previous attempts to "fix" the same place over and over. (https://lore.kernel.org/ is at your service to dive into mail archives) -- With Best Regards, Andy Shevchenko