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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 EF84FC433FF for ; Wed, 14 Aug 2019 17:27:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C47DF20665 for ; Wed, 14 Aug 2019 17:27:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565803644; bh=7oC41y1/DvvtuaK/R0aXPzmQz9Z45akuQkvn+dDeXj4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=gjqa2f+HvXSiJjKAWn02EwZcCXMnqAyUzqWWfiSIwBhhgSlYxbqqL3C7VRz1oE7DP CK1F2kAu1HKOo+97iP1pd39uJaVouT8jbVK9AlnTKhHBum3u/XtR8tRutlcOT8dSMI kQ0q+1uxgW0TkA8Rkf03oVQ7u+aTssoiCHjtJBjY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728172AbfHNR1K (ORCPT ); Wed, 14 Aug 2019 13:27:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:52622 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729036AbfHNRDx (ORCPT ); Wed, 14 Aug 2019 13:03:53 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7E66321721; Wed, 14 Aug 2019 17:03:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565802233; bh=7oC41y1/DvvtuaK/R0aXPzmQz9Z45akuQkvn+dDeXj4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cWYytbReroHPVcsn+MvFHhHwST7A/uYDaMO3cOfcf+bkYUlEYwi/S1EleqM9+I65N gt5DonQB0aG83BvRT9NMjU5ZsNqjIsiCt2lFbW6OBv6L+aaZFHg5wmRyejvIoU+70b 66+t8JVPmrNWb529ubu7s+UJVmSQTZdHmi7s9Xfg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marc Kleine-Budde , Joakim Zhang Subject: [PATCH 5.2 046/144] can: flexcan: fix stop mode acknowledgment Date: Wed, 14 Aug 2019 19:00:02 +0200 Message-Id: <20190814165801.752037420@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190814165759.466811854@linuxfoundation.org> References: <20190814165759.466811854@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Archived-At: List-Archive: List-Post: From: Joakim Zhang commit 5f186c257fa4808bb7f14e643b9fba3e11f08a30 upstream. To enter stop mode, the CPU should manually assert a global Stop Mode request and check the acknowledgment asserted by FlexCAN. The CPU must only consider the FlexCAN in stop mode when both request and acknowledgment conditions are satisfied. Fixes: de3578c198c6 ("can: flexcan: add self wakeup support") Reported-by: Marc Kleine-Budde Signed-off-by: Joakim Zhang Cc: linux-stable # >= v5.0 Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/flexcan.c | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-) --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -400,9 +400,10 @@ static void flexcan_enable_wakeup_irq(st priv->write(reg_mcr, ®s->mcr); } -static inline void flexcan_enter_stop_mode(struct flexcan_priv *priv) +static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv) { struct flexcan_regs __iomem *regs = priv->regs; + unsigned int ackval; u32 reg_mcr; reg_mcr = priv->read(®s->mcr); @@ -412,20 +413,37 @@ static inline void flexcan_enter_stop_mo /* enable stop request */ regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr, 1 << priv->stm.req_bit, 1 << priv->stm.req_bit); + + /* get stop acknowledgment */ + if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, + ackval, ackval & (1 << priv->stm.ack_bit), + 0, FLEXCAN_TIMEOUT_US)) + return -ETIMEDOUT; + + return 0; } -static inline void flexcan_exit_stop_mode(struct flexcan_priv *priv) +static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv) { struct flexcan_regs __iomem *regs = priv->regs; + unsigned int ackval; u32 reg_mcr; /* remove stop request */ regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr, 1 << priv->stm.req_bit, 0); + /* get stop acknowledgment */ + if (regmap_read_poll_timeout(priv->stm.gpr, priv->stm.ack_gpr, + ackval, !(ackval & (1 << priv->stm.ack_bit)), + 0, FLEXCAN_TIMEOUT_US)) + return -ETIMEDOUT; + reg_mcr = priv->read(®s->mcr); reg_mcr &= ~FLEXCAN_MCR_SLF_WAK; priv->write(reg_mcr, ®s->mcr); + + return 0; } static inline void flexcan_error_irq_enable(const struct flexcan_priv *priv) @@ -1612,7 +1630,9 @@ static int __maybe_unused flexcan_suspen */ if (device_may_wakeup(device)) { enable_irq_wake(dev->irq); - flexcan_enter_stop_mode(priv); + err = flexcan_enter_stop_mode(priv); + if (err) + return err; } else { err = flexcan_chip_disable(priv); if (err) @@ -1662,10 +1682,13 @@ static int __maybe_unused flexcan_noirq_ { struct net_device *dev = dev_get_drvdata(device); struct flexcan_priv *priv = netdev_priv(dev); + int err; if (netif_running(dev) && device_may_wakeup(device)) { flexcan_enable_wakeup_irq(priv, false); - flexcan_exit_stop_mode(priv); + err = flexcan_exit_stop_mode(priv); + if (err) + return err; } return 0;