From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-713482-1519321797-2-866166894333976275 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: 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=1519321797; b=CVpJ4SSTVG4LmRg890mm5ZgQb3URNyKCwu0ddNVLGxRjUm9 7QgnWofw/KTx3L1VQTM4ogBjSUwrSJrEGg4UasQKHzBzoFNRLGCwh3wrSVZrs7Sf 1muUw7oVmE68SDAmZKKXzMDjAouX4RVkOVbLs3ucEfT+Ef5sqScESdHv1s81jD4n oiPZXJH7p48sCbIuEIIUGvjQh/eDAzbFkTwW21KgPY7rcD92hriQyGPmP7hY3vb5 ArAjHnqpSnC5foRyaCOPN54psrOgW1iER1e58/s+qP54QxMYl5jOl6lQQIWQ7VHZ RZFt1DZoGU+PGBjUhYtUTXilp8+6B6kZ3vJu7iw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1519321797; bh=3obFTH9qLPtg8DinRB+Tvv4k4q 9uq40ESBaaPIYWQzA=; b=effTPULgiRu6TpJPFmiD8TjF7NbIruHatGM36uQPMN 3AjQrpU6rbLetcfpxsgT5agoIPbErC4iqK/mcScgd7rsfjeGt21c+U73hCL9qjcR iXHC4z/GiasAaBmVOrmH1g96sphd7OJ9vDwOd1yguAdKaxJxKPPtgWOR0Nj+IVqn DhlghFCttLuGiIBnpj/8mbyRuBXAxUjSciqppCXZa+GLSftP15IuADi6RFmD6oFT Z3P5JChwwQhN1gKD5JHSN863iljlbbi+dZur/YJGLbBp3x8ioOQ7YwNNVstVlSDs yPZIo1Z5Fi0K+B0dPJs4SdGAEGk9a+eYxZbn55zK2aZQ== 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 S933446AbeBVRtz (ORCPT ); Thu, 22 Feb 2018 12:49:55 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:54863 "EHLO huawei.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S933441AbeBVRty (ORCPT ); Thu, 22 Feb 2018 12:49:54 -0500 From: John Garry To: , , , , , , CC: , , Subject: [RFC PATCH 2/2] serial: 8250_dw: support polling mode Date: Fri, 23 Feb 2018 02:42:03 +0800 Message-ID: <1519324923-196857-3-git-send-email-john.garry@huawei.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1519324923-196857-1-git-send-email-john.garry@huawei.com> References: <1519324923-196857-1-git-send-email-john.garry@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.212.75] 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: 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. Signed-off-by: John Garry --- drivers/tty/serial/8250/8250_dw.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index 28fbc8f..3154988 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -422,9 +422,10 @@ static int dw8250_probe(struct platform_device *pdev) } 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; } spin_lock_init(&p->lock); -- 1.9.1