From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-2556621-1519641983-2-18216757851593958759 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='com', MailFrom='org', XOriginatingCountry='UNK' X-Spam-charsets: plain='utf-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: linux-serial-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1519641982; b=JuRYUDWPUkP/QR7Nr4p5M0zZrdL3NAw43++9/bWk1u7Ii0J 7E+G06uEZCG5chlAMc3iToYj8cY3M/8vrz3PFB+I6oi0jeHcvbzu6CL8lbwiaUpm PEVWrsuTbXptdcDZkZIUNRoCkWDdEROG01mgzxPB4sHvme02SRKwoH1zaRNMZBuM XWEp1w1FaZe4GcTUTVY8vINn9RM7lEoeGdDHArkIGBBl0U89qNpOG9uhQUzRoJuU bqxn5kVMoJqoSE8ghmxj25t2P5+6ESx+UoCzZEAxJ+DPJBfzaFMGJQuTdVUQWfg3 gUwIiHGH2wHbdpi25+GpzdbK3NApOyDcgg40osg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=subject:to:references:cc:from:message-id :date:mime-version:in-reply-to:content-type :content-transfer-encoding:sender:list-id; s=arctest; t= 1519641982; bh=cGHUiMVKLTWFNPeN5fZdaSFtkM6R0eZoBdnjrjAgcEw=; b=b VO+kSG77cY0iosgY7xqKRHvh4dnYg3ETE4c2m5hGl4sZm0sXzO2aCbEXquwTi6GJ y29mksef1mh/ADAhk+s4SK3ZeSY4S6r6jF55NNNyrHVd6IsayGY3NlGMWKHJD5Az oac33yTJTrnzywsJCYVexiW4Vzi7slUaTth5Qwo6YYuE2SYeU+EeM/ug8+lYCySl 9IA1jAJBb20JNVU+dojwIP0d47t6icATZaFM88JxJ2EmVCX4F8zkXfEcWcWMWP+6 TxBjNYABcBRnc8cE+7E74CiTzQYCLYPeF4kjup4rQdy6cJ7QiBayISAS2aj37nL7 Eb9MxuSIQE8trs7/8+qwQ== ARC-Authentication-Results: i=1; mx5.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=huawei.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-serial-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=huawei.com header.result=pass header_is_org_domain=yes Authentication-Results: mx5.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=huawei.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-serial-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=huawei.com header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752014AbeBZKqT (ORCPT ); Mon, 26 Feb 2018 05:46:19 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:5672 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751609AbeBZKqT (ORCPT ); Mon, 26 Feb 2018 05:46:19 -0500 Subject: Re: [RFC PATCH 0/2] serial: 8250_dw: IO space + polling mode support To: Andy Shevchenko , , , , , , References: <1519324923-196857-1-git-send-email-john.garry@huawei.com> <1519381801.10722.103.camel@linux.intel.com> <3c4c5f58-a661-13c8-cc1c-8d43828982cb@huawei.com> <1519407117.10722.124.camel@linux.intel.com> <88214a3e-82cc-c931-804c-7dc90fb8721f@huawei.com> <1519638828.10722.153.camel@linux.intel.com> CC: , , From: John Garry Message-ID: <7221877b-a84a-63a1-ef86-1991f358df72@huawei.com> Date: Mon, 26 Feb 2018 10:45:46 +0000 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <1519638828.10722.153.camel@linux.intel.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.238] X-CFilter-Loop: Reflected Sender: linux-serial-owner@vger.kernel.org X-Mailing-List: linux-serial@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Hi Andy, >>>> We require it for a development board for our hip06 platform. >>> >>> Okay, and this particular platform uses Synopsys IP? >> >> As I see this uart is really a virtual 8250, so HW details like apb >> clocks and the like are hidden, so may not be relevant. > > Good to know. > >> However I will check with the BMC team to know the specific details. > >>>>>> for supporting an 8250-compatible UART with >>>>>> the following profile/features: >>>>>> - platform device >>>>>> - polling mode (i.e. no interrupt support) >>>>>> - ACPI FW >>>>> >>>>> Elaborate this one, please. >>>> >>>> So we need to define our own HID here, and cannot use PNP >>>> compatible >>>> CID >>>> (like PNP0501) as we cannot use the 8250 PNP driver. >>> >>> Why not? What are the impediments? >>> >> >> To support the host controller for this device, we will create an >> MFD, >> i.e. platform device, per slave device. > > There is no answer here... > >>>> This is related to the Hisi LPC ACPI support, where we would >>>> create >>>> an >>>> MFD (i.e. platform device) for the UART. >>> >>> Why you can't do properly in ACPI? > > No answer here either. > > Sorry, but with this level of communication it's no go for the series. > Sorry if my answers did not tell you want you want to know. My point was that the 8250_pnp driver would be used for a pnp_device, but we are creating a platform device for this UART slave so would require a platform device driver, that which 8250_dw.c is. But I will check on pnp device support. Much appreciated, John