1 /*
2 * Copyright (C) 2023 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <cmath>
18 #include <limits>
19
20 #define LOG_TAG "AHAL_StreamAlsa"
21 #include <android-base/logging.h>
22
23 #include <Utils.h>
24 #include <audio_utils/clock.h>
25 #include <error/expected_utils.h>
26
27 #include "core-impl/StreamAlsa.h"
28
29 namespace aidl::android::hardware::audio::core {
30
StreamAlsa(StreamContext * context,const Metadata & metadata,int readWriteRetries)31 StreamAlsa::StreamAlsa(StreamContext* context, const Metadata& metadata, int readWriteRetries)
32 : StreamCommonImpl(context, metadata),
33 mBufferSizeFrames(getContext().getBufferSizeInFrames()),
34 mFrameSizeBytes(getContext().getFrameSize()),
35 mSampleRate(getContext().getSampleRate()),
36 mIsInput(isInput(metadata)),
37 mConfig(alsa::getPcmConfig(getContext(), mIsInput)),
38 mReadWriteRetries(readWriteRetries) {}
39
~StreamAlsa()40 StreamAlsa::~StreamAlsa() {
41 cleanupWorker();
42 }
43
init()44 ::android::status_t StreamAlsa::init() {
45 return mConfig.has_value() ? ::android::OK : ::android::NO_INIT;
46 }
47
drain(StreamDescriptor::DrainMode)48 ::android::status_t StreamAlsa::drain(StreamDescriptor::DrainMode) {
49 if (!mIsInput) {
50 static constexpr float kMicrosPerSecond = MICROS_PER_SECOND;
51 const size_t delayUs = static_cast<size_t>(
52 std::roundf(mBufferSizeFrames * kMicrosPerSecond / mSampleRate));
53 usleep(delayUs);
54 }
55 return ::android::OK;
56 }
57
flush()58 ::android::status_t StreamAlsa::flush() {
59 return ::android::OK;
60 }
61
pause()62 ::android::status_t StreamAlsa::pause() {
63 return ::android::OK;
64 }
65
standby()66 ::android::status_t StreamAlsa::standby() {
67 mAlsaDeviceProxies.clear();
68 return ::android::OK;
69 }
70
start()71 ::android::status_t StreamAlsa::start() {
72 if (!mAlsaDeviceProxies.empty()) {
73 // This is a resume after a pause.
74 return ::android::OK;
75 }
76 decltype(mAlsaDeviceProxies) alsaDeviceProxies;
77 for (const auto& device : getDeviceProfiles()) {
78 if ((device.direction == PCM_OUT && mIsInput) ||
79 (device.direction == PCM_IN && !mIsInput)) {
80 continue;
81 }
82 alsa::DeviceProxy proxy;
83 if (device.isExternal) {
84 // Always ask alsa configure as required since the configuration should be supported
85 // by the connected device. That is guaranteed by `setAudioPortConfig` and
86 // `setAudioPatch`.
87 proxy = alsa::openProxyForExternalDevice(
88 device, const_cast<struct pcm_config*>(&mConfig.value()),
89 true /*require_exact_match*/);
90 } else {
91 proxy = alsa::openProxyForAttachedDevice(
92 device, const_cast<struct pcm_config*>(&mConfig.value()), mBufferSizeFrames);
93 }
94 if (proxy.get() == nullptr) {
95 return ::android::NO_INIT;
96 }
97 alsaDeviceProxies.push_back(std::move(proxy));
98 }
99 if (alsaDeviceProxies.empty()) {
100 return ::android::NO_INIT;
101 }
102 mAlsaDeviceProxies = std::move(alsaDeviceProxies);
103 return ::android::OK;
104 }
105
transfer(void * buffer,size_t frameCount,size_t * actualFrameCount,int32_t * latencyMs)106 ::android::status_t StreamAlsa::transfer(void* buffer, size_t frameCount, size_t* actualFrameCount,
107 int32_t* latencyMs) {
108 if (mAlsaDeviceProxies.empty()) {
109 LOG(FATAL) << __func__ << ": no opened devices";
110 return ::android::NO_INIT;
111 }
112 const size_t bytesToTransfer = frameCount * mFrameSizeBytes;
113 unsigned maxLatency = 0;
114 if (mIsInput) {
115 // For input case, only support single device.
116 proxy_read_with_retries(mAlsaDeviceProxies[0].get(), buffer, bytesToTransfer,
117 mReadWriteRetries);
118 maxLatency = proxy_get_latency(mAlsaDeviceProxies[0].get());
119 } else {
120 alsa::applyGain(buffer, mGain, bytesToTransfer, mConfig.value().format, mConfig->channels);
121 for (auto& proxy : mAlsaDeviceProxies) {
122 proxy_write_with_retries(proxy.get(), buffer, bytesToTransfer, mReadWriteRetries);
123 maxLatency = std::max(maxLatency, proxy_get_latency(proxy.get()));
124 }
125 }
126 *actualFrameCount = frameCount;
127 maxLatency = std::min(maxLatency, static_cast<unsigned>(std::numeric_limits<int32_t>::max()));
128 *latencyMs = maxLatency;
129 return ::android::OK;
130 }
131
refinePosition(StreamDescriptor::Position * position)132 ::android::status_t StreamAlsa::refinePosition(StreamDescriptor::Position* position) {
133 if (mAlsaDeviceProxies.empty()) {
134 LOG(WARNING) << __func__ << ": no opened devices";
135 return ::android::NO_INIT;
136 }
137 // Since the proxy can only count transferred frames since its creation,
138 // we override its counter value with ours and let it to correct for buffered frames.
139 alsa::resetTransferredFrames(mAlsaDeviceProxies[0], position->frames);
140 if (mIsInput) {
141 if (int ret = proxy_get_capture_position(mAlsaDeviceProxies[0].get(), &position->frames,
142 &position->timeNs);
143 ret != 0) {
144 LOG(WARNING) << __func__ << ": failed to retrieve capture position: " << ret;
145 return ::android::INVALID_OPERATION;
146 }
147 } else {
148 uint64_t hwFrames;
149 struct timespec timestamp;
150 if (int ret = proxy_get_presentation_position(mAlsaDeviceProxies[0].get(), &hwFrames,
151 ×tamp);
152 ret == 0) {
153 if (hwFrames > std::numeric_limits<int64_t>::max()) {
154 hwFrames -= std::numeric_limits<int64_t>::max();
155 }
156 position->frames = static_cast<int64_t>(hwFrames);
157 position->timeNs = audio_utils_ns_from_timespec(×tamp);
158 } else {
159 LOG(WARNING) << __func__ << ": failed to retrieve presentation position: " << ret;
160 return ::android::INVALID_OPERATION;
161 }
162 }
163 return ::android::OK;
164 }
165
shutdown()166 void StreamAlsa::shutdown() {
167 mAlsaDeviceProxies.clear();
168 }
169
setGain(float gain)170 ndk::ScopedAStatus StreamAlsa::setGain(float gain) {
171 mGain = gain;
172 return ndk::ScopedAStatus::ok();
173 }
174
175 } // namespace aidl::android::hardware::audio::core
176