From patchwork Fri Mar 19 20:16:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Manish Mandlik X-Patchwork-Id: 404892 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 7A775C433DB for ; Fri, 19 Mar 2021 20:17:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2F68F61976 for ; Fri, 19 Mar 2021 20:17:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230226AbhCSURE (ORCPT ); Fri, 19 Mar 2021 16:17:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229912AbhCSUQa (ORCPT ); Fri, 19 Mar 2021 16:16:30 -0400 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2F271C06175F for ; Fri, 19 Mar 2021 13:16:30 -0700 (PDT) Received: by mail-pf1-x44a.google.com with SMTP id s18so26870296pfe.10 for ; Fri, 19 Mar 2021 13:16:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc :content-transfer-encoding; bh=FUzDMOWW+Puyz+SzWC3asQVTMfryGObB0RiZstJMIBU=; b=sgWArQyN8QTzOSH9Gn+mPcH7CA0wlJw0WRwg9RtaZL0CGmB6vEB9B2qBK8dOqOBLrE 3skODy2P8GXExoLvB11OLR8A9a9eFvmvUgfIWgqOGkbPRcOq6aSrF7bZIfbZffKqVe8X MV4r8sCleN+ffkVmElatTuxHqSKkCUVAChZjtZsZZPXL3GCY9/tvXL48MpImdKC2Rr8F fX7klLvLWWY2wpI6/HQj7ic0UPyHbIl3YWo9eZkxmyAdXeE9wAE8Mi2Ob/b3DF8bWm+A 4+ByZfFIYh5/mdGmcierXQVxk+lJB640s3qszj3uMFrNqG+5AKak7AwLddg7rIY5JaJv vVFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc :content-transfer-encoding; bh=FUzDMOWW+Puyz+SzWC3asQVTMfryGObB0RiZstJMIBU=; b=nVLczWxecUGeqgWIT0+FVrcWbmBIUxXBib4EOu8kM2vB1Yr8saOb6+9YHI9jUR3iqT a88dM6Zsj/x+Id9ilK8kwZMrrvu4OM2LPHImrYe7K3ED9TwyGE3B+VEcNs1m2NMaaFAh GfOTDj/Ujc3fWZz9psxgVgXIGymTO28iwrBfFkT8lkxVHVW9w6aLNisutzGaI3Nr4U1O 9EaBCmskjGE4BCIHHgBWVa1kj6wQhEZ2BrvC+uBC/C8weHbYWTdOgIIUtJ3WwnvT4oc6 edzloOeIkl8BHwYFpUxZOWP2ekxfIEN3wh1D2/OIoY9hLOPMRPUFSZi0QnF3er+6yRaJ PlEQ== X-Gm-Message-State: AOAM533PzuRiuL4l++kACGIzUZhqN7H2216/0SYay3WqaxCbJkDcgKF1 kyWhprwl2xp4VFvU9mGlofDlA81exhH7Zg== X-Google-Smtp-Source: ABdhPJykgo0zi/4qXykDAAUNOjL3usMtXpHDx4UnroLaxR58IPx0WFL9INya2Ev6KCQndsb9j63LruS1nXJlbg== X-Received: from mmandlik.mtv.corp.google.com ([2620:15c:202:201:fc1f:aed6:24c0:a9b0]) (user=mmandlik job=sendgmr) by 2002:a17:902:c589:b029:e6:3a39:d4a0 with SMTP id p9-20020a170902c589b02900e63a39d4a0mr16153501plx.76.1616184989509; Fri, 19 Mar 2021 13:16:29 -0700 (PDT) Date: Fri, 19 Mar 2021 13:16:05 -0700 Message-Id: <20210319131533.v1.1.I14da3750a343d8d48921fffb7c6561337b6e6082@changeid> Mime-Version: 1.0 X-Mailer: git-send-email 2.31.0.rc2.261.g7f71774620-goog Subject: [PATCH v1] Bluetooth: Add ncmd=0 recovery handling From: Manish Mandlik To: marcel@holtmann.org, luiz.dentz@gmail.com Cc: Alain Michaud , chromeos-bluetooth-upstreaming@chromium.org, linux-bluetooth@vger.kernel.org, Manish Mandlik , Abhishek Pandit-Subedi , "David S. Miller" , Jakub Kicinski , Johan Hedberg , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org During command status or command complete event, the controller may set ncmd=0 indicating that it is not accepting any more commands. In such a case, host holds off sending any more commands to the controller. If the controller doesn't recover from such condition, host will wait forever. This patch adds a timer when controller gets into such condition and resets the controller if controller doesn't recover within the timeout period. Reviewed-by: Abhishek Pandit-Subedi Signed-off-by: Manish Mandlik --- Hello Maintainers, We noticed that during suspend, sometimes the controller firmware gets into a state where it is not accepting any more commands (it returns ncmd=0 in Command Status): < HCI Command: Disconnect (0x01|0x0006) plen 3  #398 [hci0] 83.760502         Handle: 1         Reason: Remote Device Terminated due to Power Off (0x15) > HCI Event: Command Status (0x0f) plen 4       #399 [hci0] 83.761694       Disconnect (0x01|0x0006) ncmd 0         Status: Success (0x00) In such a case, the host holds off sending any more packets to the controller until it is ready to accept more commands. If the controller doesn't recover from such a condition, Command Timeout does not get triggered as Command Timeout is queued only once the packet is sent to the controller; hence, the host will wait forever.  This patch adds a timer to recover from this condition. Since the suspend timeout is 2 seconds, I'm using 4 seconds timeout to recover from ncmd=0. This should give ample amount of time for recovery and should not create any race conditions with the suspend. Once we resume from the suspend normally, the timer would expire and reset the controller. I have verified this patch locally and able to connect to peer device after resume from suspend. Please let me know your thoughts on this. Thanks, Manish. include/net/bluetooth/hci.h | 1 + include/net/bluetooth/hci_core.h | 1 + net/bluetooth/hci_core.c | 15 +++++++++++++++ net/bluetooth/hci_event.c | 10 ++++++++++ 4 files changed, 27 insertions(+) diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index ea4ae551c426..c4b0650fb9ae 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -339,6 +339,7 @@ enum { #define HCI_PAIRING_TIMEOUT msecs_to_jiffies(60000) /* 60 seconds */ #define HCI_INIT_TIMEOUT msecs_to_jiffies(10000) /* 10 seconds */ #define HCI_CMD_TIMEOUT msecs_to_jiffies(2000) /* 2 seconds */ +#define HCI_NCMD_TIMEOUT msecs_to_jiffies(4000) /* 4 seconds */ #define HCI_ACL_TX_TIMEOUT msecs_to_jiffies(45000) /* 45 seconds */ #define HCI_AUTO_OFF_TIMEOUT msecs_to_jiffies(2000) /* 2 seconds */ #define HCI_POWER_OFF_TIMEOUT msecs_to_jiffies(5000) /* 5 seconds */ diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index ebdd4afe30d2..f14692b39fd5 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -470,6 +470,7 @@ struct hci_dev { struct delayed_work service_cache; struct delayed_work cmd_timer; + struct delayed_work ncmd_timer; struct work_struct rx_work; struct work_struct cmd_work; diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index b0d9c36acc03..5ee1609456bd 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -2769,6 +2769,20 @@ static void hci_cmd_timeout(struct work_struct *work) queue_work(hdev->workqueue, &hdev->cmd_work); } +/* HCI ncmd timer function */ +static void hci_ncmd_timeout(struct work_struct *work) +{ + struct hci_dev *hdev = container_of(work, struct hci_dev, + ncmd_timer.work); + + bt_dev_err(hdev, "ncmd timeout"); + + if (hci_dev_do_close(hdev)) + return; + + hci_dev_do_open(hdev); +} + struct oob_data *hci_find_remote_oob_data(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 bdaddr_type) { @@ -3831,6 +3845,7 @@ struct hci_dev *hci_alloc_dev(void) init_waitqueue_head(&hdev->suspend_wait_q); INIT_DELAYED_WORK(&hdev->cmd_timer, hci_cmd_timeout); + INIT_DELAYED_WORK(&hdev->ncmd_timer, hci_ncmd_timeout); hci_request_setup(hdev); diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index cf2f4a0abdbd..114a9170d809 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -3635,6 +3635,11 @@ static void hci_cmd_complete_evt(struct hci_dev *hdev, struct sk_buff *skb, if (*opcode != HCI_OP_NOP) cancel_delayed_work(&hdev->cmd_timer); + if (!ev->ncmd && !test_bit(HCI_RESET, &hdev->flags)) + schedule_delayed_work(&hdev->ncmd_timer, HCI_NCMD_TIMEOUT); + else + cancel_delayed_work(&hdev->ncmd_timer); + if (ev->ncmd && !test_bit(HCI_RESET, &hdev->flags)) atomic_set(&hdev->cmd_cnt, 1); @@ -3740,6 +3745,11 @@ static void hci_cmd_status_evt(struct hci_dev *hdev, struct sk_buff *skb, if (*opcode != HCI_OP_NOP) cancel_delayed_work(&hdev->cmd_timer); + if (!ev->ncmd && !test_bit(HCI_RESET, &hdev->flags)) + schedule_delayed_work(&hdev->ncmd_timer, HCI_NCMD_TIMEOUT); + else + cancel_delayed_work(&hdev->ncmd_timer); + if (ev->ncmd && !test_bit(HCI_RESET, &hdev->flags)) atomic_set(&hdev->cmd_cnt, 1);