From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3460752-1519407321-2-17069466667460421438 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' 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=1519407320; b=wYcFFLY+EnOYRUrnz0xO8NIz1dVHRYf4AG3GehMW8xi0DdT BDS2kcBnvyT02b+4WJBQ5UURIYxjfi6NajZ5rj+xmS6DfoW9DGAPF3zZaNI88TQU ONg5cgqJXqTZC93JeVak25a2J4K7zdati8NDD/A7VfCufiJOwomBipNxLnuVwYZ8 8kzZlKXc97ait6CcvLqxShFx4U6kwoMiWq6CocSwisr5DDOKD30atQWWlkzKvF3I CnG6msZ8v/oIruZ0iguSjyhM6CeY06DEoDN7B+SfZeZuv0EAsbzvt0hxbpIcbbpd pHNlSIcAwITnRXPuSPo/v468i4nwXtzElQO7mLQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=message-id:subject:from:to:cc:date :in-reply-to:references:content-type:mime-version :content-transfer-encoding:sender:list-id; s=arctest; t= 1519407320; bh=lee2AvmSDO/qJvTO1pLFlYpjNxoKYbT35Q/JWuVGPds=; b=B FwYvYdpA2TCigcxScHAZsgO+2qQmah3EXC6RYsEOuG8TxtzU/wSkuGVofSsyIqbC f5mXwqAvqiZrw+B1Jt21CNNgyltFTQ819iEwFwZgDjoGkiV31dqA/LpGkWQuNPSL wj20Er3JWBa9AhJyq1lEohisemSX1TtvWTqPfX82wqb3g7PCPPmN4vSJ5pt8nDuS 6UwotceV/keah4XbCcVN+c4QeeB4sCiHlN5eU/863/rqmxbrcL7rTGUueYTNAx0r efRroS9I8tGYuZcHKmPserGl3XAxnKmu1ad16F28WtMmTuI6otRKfr22ixFzdiX5 tiES6X98Sj3d68pfCunkA== ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linux.intel.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=linux.intel.com header.result=pass header_org.domain=intel.com header_org.result=pass header_is_org_domain=no Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linux.intel.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=linux.intel.com header.result=pass header_org.domain=intel.com header_org.result=pass header_is_org_domain=no Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751541AbeBWRfS (ORCPT ); Fri, 23 Feb 2018 12:35:18 -0500 Received: from mga04.intel.com ([192.55.52.120]:4924 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751351AbeBWRfR (ORCPT ); Fri, 23 Feb 2018 12:35:17 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,383,1515484800"; d="scan'208";a="20579330" Message-ID: <1519407313.10722.127.camel@linux.intel.com> Subject: Re: [RFC PATCH 2/2] serial: 8250_dw: support polling mode From: Andy Shevchenko To: John Garry , gregkh@linuxfoundation.org, slaby@suse.com, p.zabel@pengutronix.de, heiko@sntech.de, ed.blake@sondrel.com, jhogan@kernel.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, linuxarm@huawei.com Date: Fri, 23 Feb 2018 19:35:13 +0200 In-Reply-To: <1519324923-196857-3-git-send-email-john.garry@huawei.com> References: <1519324923-196857-1-git-send-email-john.garry@huawei.com> <1519324923-196857-3-git-send-email-john.garry@huawei.com> Organization: Intel Finland Oy Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.5-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit 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: On Fri, 2018-02-23 at 02:42 +0800, John Garry wrote: > It would be useful to make this driver support some > 8250-compatible devices which have no interrupt line. > > For these, we allow for no interrupt, and will fallback on > polling mode. > > Note: the 8250 dt bindings state that "interrupts" > is a required property: > "interrupts : should contain uart interrupt." > > But the 8250_of.c driver can live without it. So > this patch is going this way also. It should be documented in the binding. > if (irq < 0) { > - if (irq != -EPROBE_DEFER) > - dev_err(dev, "cannot get irq\n"); > - return irq; > + if (irq == -EPROBE_DEFER) > + return irq; > + dev_warn(dev, "cannot get irq, using polling > mode\n"); > + irq = 0; NO_IRQ _is_ 0. You need to do something like if (irq < 0) } ... leave existing code ... } if (!irq) dev_warn(, "Use polling mode\n"); -- Andy Shevchenko Intel Finland Oy