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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 304AAC67790 for ; Fri, 27 Jul 2018 10:11:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6A4F2089F for ; Fri, 27 Jul 2018 10:11:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6A4F2089F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389457AbeG0LdD (ORCPT ); Fri, 27 Jul 2018 07:33:03 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:36810 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729547AbeG0LdC (ORCPT ); Fri, 27 Jul 2018 07:33:02 -0400 Received: from localhost (unknown [89.188.5.116]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 4CB88CB5; Fri, 27 Jul 2018 10:11:49 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anssi Hannula , Marc Kleine-Budde Subject: [PATCH 4.4 18/23] can: xilinx_can: fix device dropping off bus on RX overrun Date: Fri, 27 Jul 2018 12:09:19 +0200 Message-Id: <20180727100845.864140641@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180727100845.054377089@linuxfoundation.org> References: <20180727100845.054377089@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Anssi Hannula commit 2574fe54515ed3487405de329e4e9f13d7098c10 upstream. The xilinx_can driver performs a software reset when an RX overrun is detected. This causes the device to enter Configuration mode where no messages are received or transmitted. The documentation does not mention any need to perform a reset on an RX overrun, and testing by inducing an RX overflow also indicated that the device continues to work just fine without a reset. Remove the software reset. Tested with the integrated CAN on Zynq-7000 SoC. Fixes: b1201e44f50b ("can: xilinx CAN controller support") Signed-off-by: Anssi Hannula Cc: Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/xilinx_can.c | 1 - 1 file changed, 1 deletion(-) --- a/drivers/net/can/xilinx_can.c +++ b/drivers/net/can/xilinx_can.c @@ -695,7 +695,6 @@ static void xcan_err_interrupt(struct ne if (isr & XCAN_IXR_RXOFLW_MASK) { stats->rx_over_errors++; stats->rx_errors++; - priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK); if (skb) { cf->can_id |= CAN_ERR_CRTL; cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;