From patchwork Tue Oct 18 08:54:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stephan Gerhold X-Patchwork-Id: 13010219 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 4B9E7C4332F for ; Tue, 18 Oct 2022 09:46:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230083AbiJRJqH (ORCPT ); Tue, 18 Oct 2022 05:46:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230134AbiJRJqE (ORCPT ); Tue, 18 Oct 2022 05:46:04 -0400 X-Greylist: delayed 1802 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Tue, 18 Oct 2022 02:45:59 PDT Received: from mx.kernkonzept.com (serv1.kernkonzept.com [159.69.200.6]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2ABE7AC38; Tue, 18 Oct 2022 02:45:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kernkonzept.com; s=mx1; h=Content-Transfer-Encoding:MIME-Version:Message-Id :Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=WpWYwTYU7VPbUT/8IwK708XDp96RqIHUhw4ztScfS/g=; b=WeURiJsFXt2QMHdup0+z/fhFRO 466j9Y1ZZT/dOCZpN9BlZwtwhMvTjIyHYfbq+uQgdIGqfxasiQP61u8tcclGF1wXHwrQnQGnyEyuM k1irPiqNwJn7yE1KsyRVKYy8kKtKbEo8npatUR7+3tYhONE8AdhAFb7vCb+qecdEN7j1Cz12v8rY0 qBrCOYjopr7m+aeiFA3KKMIdaKSymrbiJETai/ct9xY3JV29rE89r510KEWaJaaC/R1hASeMBTh6+ RhOJWHPZLKjQqNIrqRbJdM64dIQcLNcQrwqAKQV1t9p4zxCit1ZtIb0k6w7+AzyTsrgxtfnjlyVuW PBomSWVQ==; Received: from [10.22.3.24] (helo=kernkonzept.com) by mx.kernkonzept.com with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94.2) id 1okiNm-001XAD-S3; Tue, 18 Oct 2022 10:55:30 +0200 From: Stephan Gerhold To: Luiz Augusto von Dentz , Marcel Holtmann , Johan Hedberg Cc: Andy Gross , Bjorn Andersson , linux-arm-msm@vger.kernel.org, linux-bluetooth@vger.kernel.org, Stephan Gerhold , Paul Menzel , Stephan Gerhold Subject: [PATCH RESEND v2] Bluetooth: btqcomsmd: Fix command timeout after setting BD address Date: Tue, 18 Oct 2022 10:54:31 +0200 Message-Id: <20221018085431.2913217-1-stephan.gerhold@kernkonzept.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org On most devices using the btqcomsmd driver (e.g. the DragonBoard 410c and other devices based on the Qualcomm MSM8916/MSM8909/... SoCs) the Bluetooth firmware seems to become unresponsive for a while after setting the BD address. On recent kernel versions (at least 5.17+) this often causes timeouts for subsequent commands, e.g. the HCI reset sent by the Bluetooth core during initialization: Bluetooth: hci0: Opcode 0x c03 failed: -110 Unfortunately this behavior does not seem to be documented anywhere. Experimentation suggests that the minimum necessary delay to avoid the problem is ~150us. However, to be sure add a sleep for > 1ms in case it is a bit longer on other firmware versions. Older kernel versions are likely also affected, although perhaps with slightly different errors or less probability. Side effects can easily hide the issue in most cases, e.g. unrelated incoming interrupts that cause the necessary delay. Fixes: 1511cc750c3d ("Bluetooth: Introduce Qualcomm WCNSS SMD based HCI driver") Signed-off-by: Stephan Gerhold --- (Unmodified resend of the v2 I sent back in June, it seems to have disappeared from patchwork) I tested this using a script that reboots repeatedly and checks for the error. With this patch, BT shows up successfully for 100+ consecutive boots. Without this patch it usually fails after 1-5 boots (or even always on some boards). Changes in v2: - Clarify commit message: Add affected devices and kernel versions --- drivers/bluetooth/btqcomsmd.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/bluetooth/btqcomsmd.c b/drivers/bluetooth/btqcomsmd.c index 2acb719e596f..11c7e04bf394 100644 --- a/drivers/bluetooth/btqcomsmd.c +++ b/drivers/bluetooth/btqcomsmd.c @@ -122,6 +122,21 @@ static int btqcomsmd_setup(struct hci_dev *hdev) return 0; } +static int btqcomsmd_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr) +{ + int ret; + + ret = qca_set_bdaddr_rome(hdev, bdaddr); + if (ret) + return ret; + + /* The firmware stops responding for a while after setting the bdaddr, + * causing timeouts for subsequent commands. Sleep a bit to avoid this. + */ + usleep_range(1000, 10000); + return 0; +} + static int btqcomsmd_probe(struct platform_device *pdev) { struct btqcomsmd *btq; @@ -162,7 +177,7 @@ static int btqcomsmd_probe(struct platform_device *pdev) hdev->close = btqcomsmd_close; hdev->send = btqcomsmd_send; hdev->setup = btqcomsmd_setup; - hdev->set_bdaddr = qca_set_bdaddr_rome; + hdev->set_bdaddr = btqcomsmd_set_bdaddr; ret = hci_register_dev(hdev); if (ret < 0)