From patchwork Fri Dec 15 21:49:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 13494983 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (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 DA05E138761; Fri, 15 Dec 2023 21:50:48 +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="LS5lD6PN" Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 3BFLF22m025789; Fri, 15 Dec 2023 21:50:18 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=LS5lD6PN1BKOEsZNkkhOItOoijCli/y9gWIO vW7UuyC0WbzHMubx13CPzXn+QsJHjhFWGKhXb+j6Itpf2SsU6VxetBhBQRDB0hei KPI/reCj3uO2FBUdMY7Rirl+R5fDcZEoAEjBDstdOug2hTvUPbusbmMJ8Iv+39NA nqpG5QRpi8MCcajnVLK4BNCuiqpKnpMpb2mTtIRBbOWviLFByDHmGrThOwxPPeB+ g8E1ic1RNYIGwRolPoBc68Ml6ilzUf7ZQB9F73KSCWCZ+zPcLxjE97r08bwPIwSd H/MuvR5zTv2+RXNMREXdjxgm7iZg4yE0///C2YK6KJEbyj5Bvw== Received: from nalasppmta04.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3v0w1989h3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 15 Dec 2023 21:50:18 +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 3BFLoHU0031505 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 15 Dec 2023 21:50:17 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; Fri, 15 Dec 2023 13:50:17 -0800 From: Wesley Cheng To: , , , , , , , , , , , , , , , CC: , , , , , , , Wesley Cheng Subject: [PATCH v10 39/41] ASoC: usb: Rediscover USB SND devices on USB port add Date: Fri, 15 Dec 2023 13:49:53 -0800 Message-ID: <20231215214955.12110-40-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20231215214955.12110-1-quic_wcheng@quicinc.com> References: <20231215214955.12110-1-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: nalasex01c.na.qualcomm.com (10.47.97.35) 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: 6T2RwhlcRHVJbQugvxidi5KQ6qGSa68h X-Proofpoint-ORIG-GUID: 6T2RwhlcRHVJbQugvxidi5KQ6qGSa68h 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_01,2023-12-07_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 mlxlogscore=999 suspectscore=0 mlxscore=0 impostorscore=0 lowpriorityscore=0 spamscore=0 adultscore=0 phishscore=0 clxscore=1015 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2311290000 definitions=main-2312150152 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);