From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 356C8C43381 for ; Fri, 22 Mar 2019 15:50:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0DBD621841 for ; Fri, 22 Mar 2019 15:50:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728008AbfCVPud (ORCPT ); Fri, 22 Mar 2019 11:50:33 -0400 Received: from mout.kundenserver.de ([212.227.17.10]:36815 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727363AbfCVPuc (ORCPT ); Fri, 22 Mar 2019 11:50:32 -0400 Received: from wuerfel.lan ([149.172.19.189]) by mrelayeu.kundenserver.de (mreue108 [212.227.15.145]) with ESMTPA (Nemesis) id 1Mekzb-1gWvHE0xEr-00ajAd; Fri, 22 Mar 2019 16:49:41 +0100 From: Arnd Bergmann To: stable@vger.kernel.org, Greg Kroah-Hartman , Jiri Slaby , Orson Zhai , Baolin Wang , Chunyan Zhang Cc: Lanqing Liu , Chunyan Zhang , Arnd Bergmann , Lanqing Liu , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [BACKPORT 4.4.y 23/25] serial: sprd: clear timeout interrupt only rather than all interrupts Date: Fri, 22 Mar 2019 16:44:14 +0100 Message-Id: <20190322154425.3852517-24-arnd@arndb.de> X-Mailer: git-send-email 2.20.0 In-Reply-To: <20190322154425.3852517-1-arnd@arndb.de> References: <20190322154425.3852517-1-arnd@arndb.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K1:PsIPU5iB1xBa5v+WazbuNdzqA4mLLTpIT/uM/wir9xmBeICdEOl UCw4EkoxW5ya6R+rWhfhWa6CrpEV0UXiQ7ozxDNzguNZNFcrZ9IHmtjWiR+X3mChBqXh3sC yEr+wEbKBOpTsK6fFTziPo+iFeeJuFG6n3qDJTjMbOY48FkXw9WY3xKPxmFaSNChy8ONCkV FEGBZd6oxtzWbM5XUlrvQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:UYxcQTad6wk=:G49kiHoDPXJ0UQ2KyQlZlg pIjPzzLMgjXCJbwxZq43V0JrLrHOJ3csPyEAgynOvEa6ujyxBYxECg9K3ywNyJAmRB+86Msdo 3rVYJmQ6H+rqukEri5p+pyTbvBmIZonsxEE46+kmWk2sCZLsKcDBn+3VCoUda7gdqbOWZao/4 gCHj+To9b23s0fXXEym7mj1ufxl0edCObikCWOww8JUQZufQGeI+RVYsLcAej9OIRvAJSEisP d+KVXrpNbw+sw84krKa46QSZqDncqo0q/eaDQNv9ppQjbw0EVxuEX1wp9b7i1du6pCtUIe/2S MinfqZKzM1N4HpZOH7w8zoacAJ/q6QTxH+0epsrk8BKa+GOuqlLQXtj4A9/ZvJ0cWMytpP8OX IH2m+9M8PZzVuLTS9UldI/ZxOtJTZTUIDtQV1TpYZQmfAqizK1pOflm30JnlAJ+AvoaYWpYu5 u7t8hwucKefny0KZYCYXuTBrdEeiK5pf3+o2l0T8WbHLTM89qn9BzosNvjYECoDEi6Ot2lsON U3q5N2Z5q5fNViLRYPD+knySm8te9de/W/FCatnzTbjcNA6SBKZToEqH8aqscstovAL/thoBE n6MCJYmmRG1yCXLSnDmzu/G/csUjpQr7blOlKLSImQkQWp0iL08wDe4r4L+cp2jzs1OLt6So6 riGlPBmBWiR/qrIrurwss4gqsI2Q23ny3c2GDyzxpYgCG54vTAHjbREySL0DSb4tavKPezvAQ 6ru4cLIoC76GiwcZZ7OS0zzAPNU7yLlxy4Sk6Q== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lanqing Liu On Spreadtrum's serial device, nearly all of interrupts would be cleared by hardware except timeout interrupt. This patch removed the operation of clearing all interrupt in irq handler, instead added an if statement to check if the timeout interrupt is supposed to be cleared. Wrongly clearing timeout interrupt would lead to uart data stay in rx fifo, that means the driver cannot read them out anymore. Signed-off-by: Lanqing Liu Signed-off-by: Chunyan Zhang Signed-off-by: Greg Kroah-Hartman (cherry picked from commit 4350782570b919f254c1e083261a21c19fcaee90) Signed-off-by: Arnd Bergmann --- drivers/tty/serial/sprd_serial.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c index 176f0a2bf9d9..c894eca57e73 100644 --- a/drivers/tty/serial/sprd_serial.c +++ b/drivers/tty/serial/sprd_serial.c @@ -63,6 +63,7 @@ /* interrupt clear register */ #define SPRD_ICLR 0x0014 +#define SPRD_ICLR_TIMEOUT BIT(13) /* line control register */ #define SPRD_LCR 0x0018 @@ -298,7 +299,8 @@ static irqreturn_t sprd_handle_irq(int irq, void *dev_id) return IRQ_NONE; } - serial_out(port, SPRD_ICLR, ~0); + if (ims & SPRD_IMSR_TIMEOUT) + serial_out(port, SPRD_ICLR, SPRD_ICLR_TIMEOUT); if (ims & (SPRD_IMSR_RX_FIFO_FULL | SPRD_IMSR_BREAK_DETECT | SPRD_IMSR_TIMEOUT)) -- 2.20.0