From nobody Mon Sep 16 19:28:10 2024 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 DEBDD54BE9; Tue, 13 Feb 2024 00:55:02 +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=1707785706; cv=none; b=GBBz+EmoS6zbMRat9iiQwMXt9r5r/YyUv2Z9bePwXztXvocclOFwMt/pI/xkKjgXRNd9EUWixu3+qrpXZoxwFO514DkURTP27CVF5+xXJgDlO5ihmeDaYqi+C8672Y35RjWn4gq0XgmrQdcCDia6MyrgZh0hIb78SvztJkmAV+w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707785706; c=relaxed/simple; bh=Fqp+nqEMA818GJLwPboxe/su73wTeKWl5fU2OQYtsJ0=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=dfPsb4BdTD3aWnjbq6saGqVO5eAODBv5Ut6MFLH24lah0ukfIf7nFcntxQFD4zlQ+rUPTVbzlDOFbBaRE6MHIwceezb14h6kjjwW7fIAcVjd+illqW//YflBtL37FigIz0g17+8ymN4Ufp5O+h+uy26yNpwUFgX0TMm0xgjc6hc= 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=VAyNbKvD; 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="VAyNbKvD" Received: from pps.filterd (m0279869.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 41D0093L017547; Tue, 13 Feb 2024 00:54:43 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=NAUoHGZ4M65j67wMqPq9 5kfl0u86VFJ/0phYKQEzjDY=; b=VAyNbKvDX8sAi14C6UNFYTDfm1wGZtC0kcDO uCSH4a9xvxJ6jcaopLIm0RGA+q+ca5duEUx+vkL9+yfKEJ1kVE1q2kOCYE6etUQj Qzr/gjGxaA5axr3F1/ZlfMc/f/jwErBWITXhwknQYFvABpf9+EWlDvrJ8OHSMRsn nD2oX4qV7bX0kjK0DhYp0H53LoLSuQpW29pFHCjaoWdGEOJA1IXlEnPvYH6uqfsH nipgcP68N3m00x+D4sQVH6Oka5Nc+moBkQ0n79lsUfwd5T3ZjgdjVDvis/YssxNe 9sPdetSCFACKjcakmZ4ju64F7qePImVUUTJrQFrU078/8mtCcQ== Received: from nalasppmta01.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3w7wfy82j4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 13 Feb 2024 00:54:43 +0000 (GMT) Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 41D0sge5016285 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 13 Feb 2024 00:54:42 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; Mon, 12 Feb 2024 16:54:41 -0800 From: Wesley Cheng To: , , , , , , , , , , , , , , CC: , , , , , , , Wesley Cheng Subject: [PATCH v15 33/50] ALSA: usb-audio: Prevent starting of audio stream if in use Date: Mon, 12 Feb 2024 16:54:05 -0800 Message-ID: <20240213005422.3121-34-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20240213005422.3121-1-quic_wcheng@quicinc.com> References: <20240213005422.3121-1-quic_wcheng@quicinc.com> Precedence: bulk X-Mailing-List: linux-kernel@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: vuqBfeKDwe4JWQKQVnjzzN8pVOnpiAsY X-Proofpoint-ORIG-GUID: vuqBfeKDwe4JWQKQVnjzzN8pVOnpiAsY X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-02-12_20,2024-02-12_03,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 priorityscore=1501 clxscore=1015 mlxscore=0 lowpriorityscore=0 bulkscore=0 phishscore=0 malwarescore=0 impostorscore=0 spamscore=0 suspectscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2401310000 definitions=main-2402130005 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" With USB audio offloading, an audio session is started from the ASoC platform sound card and PCM devices. Likewise, the USB SND path is still readily available for use, in case the non-offload path is desired. In order to prevent the two entities from attempting to use the USB bus, introduce a flag that determines when either paths are in use. If a PCM device is already in use, the check will return an error to userspace notifying that the stream is currently busy. This ensures that only one path is using the USB substream. Signed-off-by: Wesley Cheng --- sound/usb/card.h | 1 + sound/usb/pcm.c | 29 ++++++++++++++++++++++++++--- 2 files changed, 27 insertions(+), 3 deletions(-) diff --git a/sound/usb/card.h b/sound/usb/card.h index 4d4a6b09d7e8..2c8c51c8b1ea 100644 --- a/sound/usb/card.h +++ b/sound/usb/card.h @@ -165,6 +165,7 @@ struct snd_usb_substream { unsigned int pkt_offset_adj; /* Bytes to drop from beginning of packets (= for non-compliant devices) */ unsigned int stream_offset_adj; /* Bytes to drop from beginning of stream= (for non-compliant devices) */ =20 + unsigned int opened:1; /* pcm device opened */ unsigned int running: 1; /* running status */ unsigned int period_elapsed_pending; /* delay period handling */ =20 diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index 3adb09ce1702..3e6d33de6ce6 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -1241,8 +1241,17 @@ static int snd_usb_pcm_open(struct snd_pcm_substream= *substream) struct snd_usb_stream *as =3D snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime =3D substream->runtime; struct snd_usb_substream *subs =3D &as->substream[direction]; + struct snd_usb_audio *chip =3D subs->stream->chip; int ret; =20 + mutex_lock(&chip->mutex); + if (subs->opened) { + mutex_unlock(&chip->mutex); + return -EBUSY; + } + subs->opened =3D 1; + mutex_unlock(&chip->mutex); + runtime->hw =3D snd_usb_hardware; /* need an explicit sync to catch applptr update in low-latency mode */ if (direction =3D=3D SNDRV_PCM_STREAM_PLAYBACK && @@ -1259,13 +1268,23 @@ static int snd_usb_pcm_open(struct snd_pcm_substrea= m *substream) =20 ret =3D setup_hw_info(runtime, subs); if (ret < 0) - return ret; + goto err_open; ret =3D snd_usb_autoresume(subs->stream->chip); if (ret < 0) - return ret; + goto err_open; ret =3D snd_media_stream_init(subs, as->pcm, direction); if (ret < 0) - snd_usb_autosuspend(subs->stream->chip); + goto err_resume; + + return 0; + +err_resume: + snd_usb_autosuspend(subs->stream->chip); +err_open: + mutex_lock(&chip->mutex); + subs->opened =3D 0; + mutex_unlock(&chip->mutex); + return ret; } =20 @@ -1274,6 +1293,7 @@ static int snd_usb_pcm_close(struct snd_pcm_substream= *substream) int direction =3D substream->stream; struct snd_usb_stream *as =3D snd_pcm_substream_chip(substream); struct snd_usb_substream *subs =3D &as->substream[direction]; + struct snd_usb_audio *chip =3D subs->stream->chip; int ret; =20 snd_media_stop_pipeline(subs); @@ -1287,6 +1307,9 @@ static int snd_usb_pcm_close(struct snd_pcm_substream= *substream) =20 subs->pcm_substream =3D NULL; snd_usb_autosuspend(subs->stream->chip); + mutex_lock(&chip->mutex); + subs->opened =3D 0; + mutex_unlock(&chip->mutex); =20 return 0; }