From patchwork Tue Jan 2 21:45:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 760032 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 301821CF88; Tue, 2 Jan 2024 21:46:55 +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="LEjDi66q" Received: from pps.filterd (m0279873.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 402LCxNa015036; Tue, 2 Jan 2024 21:46:26 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=Mac5fYtyQT3/dFjHQIR2 0e2Ic8f2mGSavzPia8fsM5c=; b=LEjDi66qM70lB+j3OWYK90QlZp3oNPXyRt6o Dx/u205B7EuVAcxeyLvZCIWj9klAu1nHmhk39eRsmfiwOU7g5TYRQxSxotugrMbV Q89heUfgyXr3E0lPXGQDgzW9zMemImLeyJVfmf3ChzbagVGUMEUHPjueu9krHvTZ XHTpVB3fzat3NGkNTIOaLvE1SEkXU7yeOxc3bc7TEf7jv8Buj4cH3CT6XRTQJNEB 8H4wTb4lAWmcZnH1Jc6Xe3XC69IEBlyfTjw83PxRD/5M5P2bA0CzsYKuKqqzFYkh QujFuqyBqQDtSg9RXOITGxu10u6keBNjGo7NtEGNLC5i4fNuag== Received: from nalasppmta01.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3vcgku9a6j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 02 Jan 2024 21:46:25 +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 402LkPxn009872 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 2 Jan 2024 21:46:25 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; Tue, 2 Jan 2024 13:46:24 -0800 From: Wesley Cheng To: , , , , , , , , , , , , , , , CC: , , , , , , , Wesley Cheng Subject: [PATCH v12 23/41] ALSA: usb-audio: Prevent starting of audio stream if in use Date: Tue, 2 Jan 2024 13:45:31 -0800 Message-ID: <20240102214549.22498-24-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20240102214549.22498-1-quic_wcheng@quicinc.com> References: <20240102214549.22498-1-quic_wcheng@quicinc.com> Precedence: bulk X-Mailing-List: devicetree@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: mMN_EIqlwbEggV2bRkSWiMiXDW1qheIU X-Proofpoint-ORIG-GUID: mMN_EIqlwbEggV2bRkSWiMiXDW1qheIU 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 bulkscore=0 mlxscore=0 malwarescore=0 adultscore=0 clxscore=1015 phishscore=0 mlxlogscore=999 lowpriorityscore=0 priorityscore=1501 impostorscore=0 spamscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2311290000 definitions=main-2401020161 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 | 19 +++++++++++++++++-- 2 files changed, 18 insertions(+), 2 deletions(-) diff --git a/sound/usb/card.h b/sound/usb/card.h index ed4a664e24e5..6d59995440c3 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) */ + unsigned int opened:1; /* pcm device opened */ unsigned int running: 1; /* running status */ unsigned int period_elapsed_pending; /* delay period handling */ diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index 3adb09ce1702..c2cb52cd5d23 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -1241,8 +1241,15 @@ static int snd_usb_pcm_open(struct snd_pcm_substream *substream) struct snd_usb_stream *as = snd_pcm_substream_chip(substream); struct snd_pcm_runtime *runtime = substream->runtime; struct snd_usb_substream *subs = &as->substream[direction]; + struct snd_usb_audio *chip = subs->stream->chip; int ret; + mutex_lock(&chip->mutex); + if (subs->opened) { + mutex_unlock(&chip->mutex); + return -EBUSY; + } + runtime->hw = snd_usb_hardware; /* need an explicit sync to catch applptr update in low-latency mode */ if (direction == SNDRV_PCM_STREAM_PLAYBACK && @@ -1259,13 +1266,17 @@ static int snd_usb_pcm_open(struct snd_pcm_substream *substream) ret = setup_hw_info(runtime, subs); if (ret < 0) - return ret; + goto out; ret = snd_usb_autoresume(subs->stream->chip); if (ret < 0) - return ret; + goto out; ret = snd_media_stream_init(subs, as->pcm, direction); if (ret < 0) snd_usb_autosuspend(subs->stream->chip); + subs->opened = 1; +out: + mutex_unlock(&chip->mutex); + return ret; } @@ -1274,6 +1285,7 @@ static int snd_usb_pcm_close(struct snd_pcm_substream *substream) int direction = substream->stream; struct snd_usb_stream *as = snd_pcm_substream_chip(substream); struct snd_usb_substream *subs = &as->substream[direction]; + struct snd_usb_audio *chip = subs->stream->chip; int ret; snd_media_stop_pipeline(subs); @@ -1287,6 +1299,9 @@ static int snd_usb_pcm_close(struct snd_pcm_substream *substream) subs->pcm_substream = NULL; snd_usb_autosuspend(subs->stream->chip); + mutex_lock(&chip->mutex); + subs->opened = 0; + mutex_unlock(&chip->mutex); return 0; }