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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 9498CC43441 for ; Sun, 11 Nov 2018 20:26:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5905220818 for ; Sun, 11 Nov 2018 20:26:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5905220818 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk 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 S1730714AbeKLGPR (ORCPT ); Mon, 12 Nov 2018 01:15:17 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50938 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730653AbeKLFs2 (ORCPT ); Mon, 12 Nov 2018 00:48:28 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gLvsn-0000oM-MP; Sun, 11 Nov 2018 19:58:57 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gLvsX-0001lT-RP; Sun, 11 Nov 2018 19:58:41 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Anssi Hannula" , "Marc Kleine-Budde" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 281/366] can: xilinx_can: fix device dropping off bus on RX overrun In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.61-rc1 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 Signed-off-by: Marc Kleine-Budde Signed-off-by: Ben Hutchings --- 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 @@ -598,7 +598,6 @@ 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;