From patchwork Fri May 24 00:10:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 13672576 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 B4C3725757; Fri, 24 May 2024 00:11:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716509487; cv=none; b=S+06t0VTqoOIS4nAGsI6KOP61o4fiJfJNfxqdNXKGXjeZJ3Ws/KHPThZVQndIuiXigrawr9KiJtKt8cbMbnjp1rpTDVAw34wXc0hqiEbHcPoIsswPQl2Sid5UwZTPWSdjTbpcCV+FyvW3yVGu5PrJx73WLIWRd/E3rmJ+Ciq9Gk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716509487; c=relaxed/simple; bh=JRrJ8Fm5hI+qm0drOuDhVg0hMJuUZP9PozV/Xog8KLE=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=B4f2IlUZOIDFD6ltcbFyHKOU4poY3UlBgeenpLuOgtYUxEZ+8QKFB9n8IduEAsnEWAdzOwRgzGDHvHYU2AWK1oW2bjDRiEX+usWnbmL96yo7QdwRDP7gnQYORk6O8KSC+izIxnon1US95VsVZNNuhPctqDz54Lvlu8xirA2kk/M= 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=LBod3dd/; arc=none smtp.client-ip=205.220.168.131 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="LBod3dd/" Received: from pps.filterd (m0279863.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 44NNPNX6005044; Fri, 24 May 2024 00:11:06 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= cc:content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=qcppdkim1; bh=C3TLaE8m/WOgCptyuUdKmiIh 2Vajd8/Ri4meOdX1tsM=; b=LBod3dd/MMDr3/aczw6Oy4HwCEo/Rc1j+RG49rj3 LnbYigpWYCx12qkO1ibqt7CYvalM+BUzrcrqZB4eVz9M1G8LlG/SsfvW7z2+zzwO lFJ4Bm0OBwkJuaPsAUx1DO5L00fpM6kZ3WNItiaAcZMRyTQCUvJehFxhoxsNN7+n WvpMlZEuynv5Px5Q99NjotOvVsgg0FUgqynfdOygbcoy1OZj65XuLl9ybA+/4FRr OsQxaSQiVZfPG1eKRXKJb+ettdBN6Q5mTqwp23g2btG3fTBs/PcCBVD8UbYsLj1D pPJECkXG5fCyQcUOWaPebBSkgD3Q9gGAl3PmLlRjQRCDsA== Received: from nalasppmta03.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3yaa8j0r1x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 24 May 2024 00:11:06 +0000 (GMT) Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA03.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 44O0B51a013015 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 24 May 2024 00:11:05 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 15.2.1544.9; Thu, 23 May 2024 17:11:05 -0700 From: Wesley Cheng To: , , , , , , , , , , , , CC: , , , , , , , Wesley Cheng Subject: [PATCH v22 37/38] ASoC: usb: Rediscover USB SND devices on USB port add Date: Thu, 23 May 2024 17:10:42 -0700 Message-ID: <20240524001043.10141-38-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20240524001043.10141-1-quic_wcheng@quicinc.com> References: <20240524001043.10141-1-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: nalasex01b.na.qualcomm.com (10.47.209.197) 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: q0wlsU5Rk2ZRnVs8dVDYroM3C8j_MM29 X-Proofpoint-ORIG-GUID: q0wlsU5Rk2ZRnVs8dVDYroM3C8j_MM29 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.650,FMLib:17.12.28.16 definitions=2024-05-23_13,2024-05-23_01,2024-05-17_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 mlxscore=0 clxscore=1015 phishscore=0 suspectscore=0 mlxlogscore=999 spamscore=0 adultscore=0 impostorscore=0 malwarescore=0 lowpriorityscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2405170001 definitions=main-2405230166 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 d50bcb9f379e..e708eaf05a95 100644 --- a/sound/soc/soc-usb.c +++ b/sound/soc/soc-usb.c @@ -593,6 +593,8 @@ void snd_soc_usb_add_port(struct snd_soc_usb *usb) mutex_lock(&ctx_mutex); list_add_tail(&usb->list, &usb_ctx_list); mutex_unlock(&ctx_mutex); + + snd_usb_rediscover_devices(); } EXPORT_SYMBOL_GPL(snd_soc_usb_add_port);