From patchwork Tue May 7 19:51:14 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 795458 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 67F831C0DC7; Tue, 7 May 2024 19:51:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.180.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715111525; cv=none; b=NEEbqIxZHsuGKdhveccIuSYS3t8wEUHEIUCVmZogPKSDDjUjwsCxoPJBfL4nSdNXTdb0qLYjrBpu5GvymxHEcXcZhq8GtE8K/2mx5nhX1PUP8oc5sp6SxOYZEZjG8i5RM2Ak62Dbdl5lGJ7QSwiiuP6JKmdCSYKhmeVDkhaU/WM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715111525; c=relaxed/simple; bh=aohF1H5It4rN8CPl810oOMZyUSRQ4J8V9uxQDlYzYv8=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=K9mAQ9UvZNz2km/0Q3FoQNtGz8TbbDxakGEe9Jd6yh+4gObDp6D+b6Q05hzREioIWF5NsIVfNePHRQFDVFdg7cf80z/QbnvGMcZ50Es8vwm3KAXWLOCQtJ69adZ3yXx1Tq0DiZcMjxIdSPPwpvT+M9NJuYs6dY/4vei5YlBZ/vo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com; spf=pass smtp.mailfrom=quicinc.com; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b=omVFBCgl; arc=none smtp.client-ip=205.220.180.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=quicinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="omVFBCgl" Received: from pps.filterd (m0279872.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 447IgtMA007644; Tue, 7 May 2024 19:51:39 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-type; s=qcppdkim1; bh=kgKTXHdqvQUPjTSXivSj 9cZvpgdEpKIF8Fx5Er4rXp8=; b=omVFBCgloj8UVeZ7oeyzbeeBa1A5G4+ON2YX DzLs2cj57SKVQ6yzTQZ0EWdoiX5jm6GDHytq9lsNCCly5qNqGbadYZCQWOwIhHzx pSDpOuJ6lxHZrM0skz/FgxtMS8fEVaucdaK4C3sI+7sGUcmExGuQN1oIuvJgYjbW cF+0V0+i4zbHth7s1OWCm+YZhKe2cddg/4SBc/E49xR/QwTYPEq5hliblYA7sfcr 1LgIcdezujrIAdc7kbTtZZT/TP9LGdAMEx+u2mREq9hv8zVbRAqPEkCLlje3MTGe ZXCy5CiOAsvar78HZ1w8zmAeirc+wtcRL6z6vDgmfzLQvvq+7A== Received: from nalasppmta05.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3xyste03yp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 07 May 2024 19:51:39 +0000 (GMT) Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA05.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 447Jpcvt008972 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 7 May 2024 19:51:38 GMT Received: from hu-wcheng-lv.qualcomm.com (10.49.16.6) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.9; Tue, 7 May 2024 12:51:37 -0700 From: Wesley Cheng To: , , , , , , , , , , , , , , , CC: , , , , , , , Wesley Cheng Subject: [PATCH v21 37/39] ASoC: usb: Rediscover USB SND devices on USB port add Date: Tue, 7 May 2024 12:51:14 -0700 Message-ID: <20240507195116.9464-38-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20240507195116.9464-1-quic_wcheng@quicinc.com> References: <20240507195116.9464-1-quic_wcheng@quicinc.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nalasex01a.na.qualcomm.com (10.47.209.196) To nalasex01b.na.qualcomm.com (10.47.209.197) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: yLJsMRKXDOWWQM2Li6pzngmsw99cjyDX X-Proofpoint-ORIG-GUID: yLJsMRKXDOWWQM2Li6pzngmsw99cjyDX X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.650,FMLib:17.11.176.26 definitions=2024-05-07_12,2024-05-06_02,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 phishscore=0 priorityscore=1501 malwarescore=0 mlxscore=0 bulkscore=0 clxscore=1015 mlxlogscore=999 spamscore=0 adultscore=0 suspectscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2405010000 definitions=main-2405070138 In case the USB backend device has not been initialized/probed, USB SND device connections can still occur. When the USB backend is eventually made available, previous USB SND device connections are not communicated to the USB backend. Call snd_usb_rediscover_devices() to generate the connect callbacks for all USB SND devices connected. This will allow for the USB backend to be updated with the current set of devices available. The chip array entries are all populated and removed while under the register_mutex, so going over potential race conditions: Thread#1: q6usb_component_probe() --> snd_soc_usb_add_port() --> snd_usb_rediscover_devices() --> mutex_lock(register_mutex) Thread#2 --> usb_audio_disconnect() --> mutex_lock(register_mutex) So either thread#1 or thread#2 will complete first. If Thread#1 completes before thread#2: SOC USB will notify DPCM backend of the device connection. Shortly after, once thread#2 runs, we will get a disconnect event for the connected device. Thread#2 completes before thread#1: Then during snd_usb_rediscover_devices() it won't notify of any connection for that particular chip index. Signed-off-by: Wesley Cheng --- sound/soc/soc-usb.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/sound/soc/soc-usb.c b/sound/soc/soc-usb.c index a64bfbd91bf3..457c71d2bbd0 100644 --- a/sound/soc/soc-usb.c +++ b/sound/soc/soc-usb.c @@ -584,6 +584,8 @@ int snd_soc_usb_add_port(struct snd_soc_usb *usb) list_add_tail(&usb->list, &usb_ctx_list); mutex_unlock(&ctx_mutex); + snd_usb_rediscover_devices(); + return 0; } EXPORT_SYMBOL_GPL(snd_soc_usb_add_port);