From patchwork Wed Feb 19 00:47:34 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 867448 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 A09501B960; Wed, 19 Feb 2025 00:48:23 +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=1739926105; cv=none; b=Xxy1U70KLwP9alWah/uvtNgd3vQ0aSDj7/VZgPMioGkUFc3JNIA3fLTeA21hJ7PwV5lM3qO4htyna5VU29e3Jg7oFVTSNQgEv1nXemZby6wDLtDAejUn9pPHyXXHPEOZqMja5KoRlasYu/BHtGzqEDA5BfigWfIZ/B/Fr3HRtHM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739926105; c=relaxed/simple; bh=5KJ7+nlo+guZwES5cAPb8FiXJM3/tZyf/+ePj0k54QI=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=uezmOXEOJUOfHs9EZhZkfU7HXo13j+2tZy+gee9eZy5fn2ORiFW6ZXcuFqI59/LrL0mx2RzsPVfIIUtjs6YM9ghC5pENEkOv2FRwUzuPMHLQDTJ5kYm14LWo+sENCQ5TJpj/UpPKQRiGnY0B1lDSvM+/l2Xk8aqqbb05xZXSR7w= 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=AbzwfOIs; 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="AbzwfOIs" Received: from pps.filterd (m0279864.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 51IIwMxg007567; Wed, 19 Feb 2025 00:48:08 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= s1yCIbobXIwRRl19rlXryQgqvNgUhDI2Hp1deBw+rA8=; b=AbzwfOIsHZt1WN4T VRB4E/ieoFlmtAld69Yp7FO3d/0bMfEa2Xn0PGcZSw+fN5ahAr3e2nnIBZe1yGTQ gGMOQBRY5hLjEj0YhyeGX0SNJbS7OG9IO0ABSZ5DNgsAKvWqv94sMlz+2xUbw2Rc agNSv8Ftf+f0Oiz8TbHQhzrSwcbltUQVj1gNeMpIwVTiJRzUXV1+p8edETAdtXyo 5ZECuVk5EFfOK+re/t/Br8fXDKOHQkPlJ+V0oYfs6HRRMlHt6mPAdRB/Pw/HVa+A umCGdnuxmb+9f+o/kYoxK3uoHLpLrtadZGOx4LXWP5vINAdMok2Y68Q3HPVW3TKD eZGE7Q== Received: from nalasppmta05.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 44vyy2rqv8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 19 Feb 2025 00:48:08 +0000 (GMT) Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA05.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTPS id 51J0m7jr006507 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 19 Feb 2025 00:48:07 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; Tue, 18 Feb 2025 16:48:07 -0800 From: Wesley Cheng To: , , , , , , , , , , , , , CC: , , , , , , , Wesley Cheng Subject: [PATCH v35 11/31] ALSA: usb-audio: Prevent starting of audio stream if in use Date: Tue, 18 Feb 2025 16:47:34 -0800 Message-ID: <20250219004754.497985-12-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250219004754.497985-1-quic_wcheng@quicinc.com> References: <20250219004754.497985-1-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: 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: nb66skbGFUWSHEUv7XhqaIzPAlCH2g4X X-Proofpoint-GUID: nb66skbGFUWSHEUv7XhqaIzPAlCH2g4X X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-02-18_11,2025-02-18_01,2024-11-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 adultscore=0 clxscore=1015 priorityscore=1501 suspectscore=0 mlxscore=0 bulkscore=0 impostorscore=0 spamscore=0 malwarescore=0 lowpriorityscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2502100000 definitions=main-2502190003 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. Reviewed-by: Pierre-Louis Bossart 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 b65163c60176..cdafc9e9cecd 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 18467da6fd9e..b24ee38fad72 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 = 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; + } + subs->opened = 1; + mutex_unlock(&chip->mutex); + 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 +1268,23 @@ static int snd_usb_pcm_open(struct snd_pcm_substream *substream) ret = setup_hw_info(runtime, subs); if (ret < 0) - return ret; + goto err_open; ret = snd_usb_autoresume(subs->stream->chip); if (ret < 0) - return ret; + goto err_open; ret = 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 = 0; + mutex_unlock(&chip->mutex); + return ret; } @@ -1274,6 +1293,7 @@ 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 +1307,9 @@ 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; }