From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) (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 81A7244A401; Wed, 16 Sep 2026 11:06:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789556780; cv=none; b=OWLkFDeyR8uKpiDbKwooibbkLlDbDSQNkrjrBa0Qhq+/tU1YQKocSFQFwgQk0lhpIAfnE0jfRWBYrpelGGU2+TBnWb4zoc3TdgELgoG2z4iuv4LQ0nkxoOGXr7ZM9UiHnjWlYUJxRXYA8vDrFAn/p58mnJrfq8VzuwGW5luKQHY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789556780; c=relaxed/simple; bh=HzRpDUemKObzUrc8XbP7CS1ebBC8gLFixWIizYLS1YQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=OulSIVC0KAoDM8na97NhQohd4pO8q/kflMH73nFsAQ56do/vUde0hjP24B738OIUAKK8gPP+U1O19uQCXayrp0q0AGgtO4P+84Qe1B3PXNlQP0oXfb4XrcHpbuS9QhUyaPJ9Fl9A3bHgwhes1Ou3g0FqOClyOXx7T1IKtifwQZA= 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=E4ROJ7pW; arc=none smtp.client-ip=198.175.65.11 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="E4ROJ7pW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1789556770; x=1821092770; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=HzRpDUemKObzUrc8XbP7CS1ebBC8gLFixWIizYLS1YQ=; b=E4ROJ7pWYtNqDb+0eDNUI7NnAJJpjKslEiNr7H4LNIz7azg/NjGARtdq hRg9BIdVbzCZs6JVdVxBKseUFALdx3gbrcPfrTdEcN6+Jv7dT1uHTPsPq Qtcwt5KSW89WM2B0wbKsDJaYlha34fYG2O2hkiFLywLzLSxH4tVT0nl5I C+EkbkJF8tLVCZPsxL72gODbrst0YeQlmf2SUTPIWMMR3Pv+VxJb9bNef OOxefOie9T+e0v4UmDvlZGFUIEcqHENdUQlvaUeidOefoFzszAPGjarjC GZDTzufhcszt3KfX3VRrBqkGAc9a/5hXn+dZtKth1YhKO0rIUR17R59Ez Q==; X-CSE-ConnectionGUID: NNKAlvJoRSeck5CrrUpB4Q== X-CSE-MsgGUID: XT6L5p6DRNOouNCWe12GSw== X-IronPort-AV: E=McAfee;i="6800,10657,11905"; a="100255070" X-IronPort-AV: E=Sophos;i="6.27,103,1787036400"; d="scan'208";a="100255070" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2026 04:06:04 -0700 X-CSE-ConnectionGUID: hL6MRQfjT8WMVh/W/Yapgw== X-CSE-MsgGUID: 74I0UvttTXCxG+cNXNYKTg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,103,1787036400"; d="scan'208";a="272832452" Received: from ettammin-mobl2.ger.corp.intel.com (HELO localhost) ([10.245.244.145]) by orviesa008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2026 04:06:03 -0700 Date: Wed, 16 Sep 2026 14:06:00 +0300 From: Andy Shevchenko To: Nam Cao Cc: Omer PALA , andy@kernel.org, gregkh@linuxfoundation.org, 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: fb_upd161704: replace udelay with usleep_range Message-ID: References: <20260916093928.52057-1-palaomer100@gmail.com> <87ecet5xos.fsf@yellow.woof> 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: <87ecet5xos.fsf@yellow.woof> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo On Wed, Sep 16, 2026 at 11:53:55AM +0200, Nam Cao wrote: > Omer PALA writes: ... > Btw, I am curious why we have these udelay(). Can we remove them? Once again remind people that FBTFT works for both busses: SPI and parallel, the latter one is usually GPIO-based and quite slow (I have one of the panel in this mode, it gives me ~2-3fps at best on a 10y.o. x86_64 embedded device). Maybe that's the reason? In any case, I think the datasheet on the panel should answer the question. -- With Best Regards, Andy Shevchenko