From patchwork Mon Jul 18 20:51:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Wang X-Patchwork-Id: 591636 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E560C433EF for ; Mon, 18 Jul 2022 20:51:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234603AbiGRUvo (ORCPT ); Mon, 18 Jul 2022 16:51:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229888AbiGRUvn (ORCPT ); Mon, 18 Jul 2022 16:51:43 -0400 Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86C6232464 for ; Mon, 18 Jul 2022 13:51:37 -0700 (PDT) X-UUID: 4e09c3d704e541d9a106ae5670a056f1-20220719 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.8, REQID:80d7dea7-35e1-49ed-bc5f-9a644fc98f39, OB:0, LO B:0,IP:0,URL:5,TC:0,Content:-5,EDM:0,RT:0,SF:0,FILE:0,RULE:Release_Ham,ACT ION:release,TS:0 X-CID-META: VersionHash:0f94e32, CLOUDID:f59ed0d7-5d6d-4eaf-a635-828a3ee48b7c, C OID:IGNORED,Recheck:0,SF:nil,TC:nil,Content:0,EDM:-3,IP:nil,URL:1,File:nil ,QS:nil,BEC:nil,COL:0 X-UUID: 4e09c3d704e541d9a106ae5670a056f1-20220719 Received: from mtkmbs11n2.mediatek.inc [(172.21.101.187)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1561950674; Tue, 19 Jul 2022 04:51:31 +0800 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs10n1.mediatek.inc (172.21.101.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.792.15; Tue, 19 Jul 2022 04:51:30 +0800 Received: from mtkswgap22.mediatek.inc (172.21.77.33) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.792.3 via Frontend Transport; Tue, 19 Jul 2022 04:51:30 +0800 From: To: , CC: , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH 3/4] mt76: mt7921u: fix race issue between reset and suspend/resume Date: Tue, 19 Jul 2022 04:51:25 +0800 Message-ID: <0d63c7d511269fe6f0c7c09fe922417ed594d3b3.1658176701.git.sean.wang@kernel.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: References: MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org From: Sean Wang It is unexpected that the reset work is running simultaneously with the suspend or resume context and it is possible that reset work is still running even after mt7921 is suspended if we don't fix the race issue. Thus, the suspend procedure should be waiting until the reset is completed at the beginning and ignore the subsequent the reset requests. In case there is an error that happens during either suspend or resume handler, we will schedule a reset task to recover the error before returning the error code to ensure we can immediately fix the error there. Fixes: df3e4143ba8a ("mt76: mt7921u: add suspend/resume support") Co-developed-by: YN Chen Signed-off-by: YN Chen Signed-off-by: Sean Wang --- .../net/wireless/mediatek/mt76/mt7921/usb.c | 28 ++++++++++++++++--- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/usb.c b/drivers/net/wireless/mediatek/mt76/mt7921/usb.c index dd3b8884e162..124d62c0dfa4 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/usb.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/usb.c @@ -300,11 +300,15 @@ static void mt7921u_disconnect(struct usb_interface *usb_intf) static int mt7921u_suspend(struct usb_interface *intf, pm_message_t state) { struct mt7921_dev *dev = usb_get_intfdata(intf); + struct mt76_connac_pm *pm = &dev->pm; int err; + pm->suspended = true; + cancel_work_sync(&dev->reset_work); + err = mt76_connac_mcu_set_hif_suspend(&dev->mt76, true); if (err) - return err; + goto failed; mt76u_stop_rx(&dev->mt76); mt76u_stop_tx(&dev->mt76); @@ -312,11 +316,20 @@ static int mt7921u_suspend(struct usb_interface *intf, pm_message_t state) set_bit(MT76_STATE_SUSPEND, &dev->mphy.state); return 0; + +failed: + pm->suspended = false; + + if (err < 0) + mt7921_reset(&dev->mt76); + + return err; } static int mt7921u_resume(struct usb_interface *intf) { struct mt7921_dev *dev = usb_get_intfdata(intf); + struct mt76_connac_pm *pm = &dev->pm; bool reinit = true; int err, i; @@ -338,16 +351,23 @@ static int mt7921u_resume(struct usb_interface *intf) if (reinit || mt7921_dma_need_reinit(dev)) { err = mt7921u_dma_init(dev, true); if (err) - return err; + goto failed; } clear_bit(MT76_STATE_SUSPEND, &dev->mphy.state); err = mt76u_resume_rx(&dev->mt76); if (err < 0) - return err; + goto failed; + + err = mt76_connac_mcu_set_hif_suspend(&dev->mt76, false); +failed: + pm->suspended = false; + + if (err < 0) + mt7921_reset(&dev->mt76); - return mt76_connac_mcu_set_hif_suspend(&dev->mt76, false); + return err; } #endif /* CONFIG_PM */