From patchwork Wed Dec 20 22:45:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 13500602 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 DF6DB54BDB; Wed, 20 Dec 2023 22:46:23 +0000 (UTC) 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="Vm3Xf31n" Received: from pps.filterd (m0279868.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 3BKMk7Kq009632; Wed, 20 Dec 2023 22:46:07 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=2OiOvsQD7ZWPb6z4rtLB A/HS49iLIfIToMaiUYq1eM0=; b=Vm3Xf31nxGcx3vMltuElkNYuKdWljCrsI/cb ivfI0BUTerfFbCXdq39uaYtHhAAlNoLMtZL8tlLb0jPHsAdyh1LgX4HsPpOAVK6d bgvlYo7uaY/GJWDxavj7hKHoXruXkQ3iLJFXHbMz/76GdKGdqrShJ/Qts+MDpGCG ckPCKK0FGfZudO46Lmn4KEp5HJ4+Dry6e+hpHNJrcxijI2OdKf4plccIgeU6PoYW 6cJD1kpILhhCVY+WTtnjjb35zRzR3lK3FxHRW1dzrh1ojN5xdpWtPBEiTTSjPqPN QUFz1MwzSnJR7vW5hiAAdNoY7i/oz37AshMXch8Kg5K8BK+aDw== Received: from nalasppmta04.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3v3wt9sxfq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 20 Dec 2023 22:46:06 +0000 (GMT) Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA04.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 3BKMk5Li032041 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 20 Dec 2023 22:46:05 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 15.2.1118.40; Wed, 20 Dec 2023 14:46:05 -0800 From: Wesley Cheng To: , , , , , , , , , , , , , , , CC: , , , , , , , Wesley Cheng Subject: [PATCH v11 39/41] ASoC: usb: Rediscover USB SND devices on USB port add Date: Wed, 20 Dec 2023 14:45:42 -0800 Message-ID: <20231220224544.18031-40-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20231220224544.18031-1-quic_wcheng@quicinc.com> References: <20231220224544.18031-1-quic_wcheng@quicinc.com> Precedence: bulk X-Mailing-List: linux-sound@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-ORIG-GUID: jYBzUxLtRrTxjjUCeHK7Xdz8I7XbciHR X-Proofpoint-GUID: jYBzUxLtRrTxjjUCeHK7Xdz8I7XbciHR X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.997,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-12-09_02,2023-12-07_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 mlxlogscore=999 spamscore=0 lowpriorityscore=0 mlxscore=0 suspectscore=0 adultscore=0 clxscore=1015 impostorscore=0 bulkscore=0 priorityscore=1501 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2311290000 definitions=main-2312200163 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 b272945dcab0..f22bf5c0989f 100644 --- a/sound/soc/soc-usb.c +++ b/sound/soc/soc-usb.c @@ -437,6 +437,8 @@ 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);