ALSA2020-12-09 07:06:43<p>This allows me to pick alsa in the pp_editor and it even works to send the sound to the appropriate place and play the first video. However, if I hit the downkey to move to the next video, it ...
alsa2020-12-31 03:15:28<div><p>Hi, I used Cubieboard a10 and ...But i do not find alsa )) cat /proc/asound/version cat: /proc/asound/version: No such file or directory</p><p>该提问来源于开源项目：armbian/build</p></div>
ALSA lib2021-01-07 17:39:53ALSA lib /tmp/portage/media-libs/alsa-lib-188.8.131.52/work/alsa-lib-184.108.40.206/src/pcm/pcm.c:2501:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.front ALSA lib /tmp/portage/media-libs/alsa-lib-220.127.116.11/work/...
alsa error2020-11-22 00:22:27<p>I have it working - but I am getting alsa errors and poor audio quality. I assume that they are related - but I'm not sure. <p>Here is what I am setting when I call the extension: <p>pi-1:~ $ ...
alsa problems2020-12-26 12:50:21ALSA lib pcm_dsnoop.c:618:(snd_pcm_dsnoop_open) unable to open slave ALSA lib pcm_dmix.c:1052:(snd_pcm_dmix_open) unable to open slave ALSA lib pcm.c:2495:(snd_pcm_open_noupdate) Unknown PCM cards.pcm...
ALSA error2020-11-30 13:52:44ALSA lib conf.c:4259:(_snd_config_evaluate) function snd_func_refer returned error: No such file or directory ALSA lib conf.c:4738:(snd_config_expand) Evaluate error: No such file or directory ALSA ...
Alsa underruns2021-01-07 17:31:39src/hostapi/alsa/pa_linux_alsa.c', line: 3350 Expression 'ContinuePoll( self, StreamDirection_In, &pollTimeout, &pollCapture )' failed in 'src/hostapi/alsa/pa_linux_alsa.c'...
Fixed ALSA2020-12-08 19:54:50<div><p>Added Path Binding to ALSA, to make sure alsa works under snap</p><p>该提问来源于开源项目：keshavbhatt/olivia</p></div>
Alsa Mixer2020-12-09 12:16:48<div><p>This is probably wrong as I am learning about linux and raspbiean, but im having trouble with the alsa mixer. There isn't an option in the TBOplayer and I have been trying to make it the ...
ALSA Support2020-12-31 09:19:19<div><p>I had problems running dsd in recent versions of Linux that use ...<p>PulseAudio plays better with ALSA so I added ALSA support to DSD.</p><p>该提问来源于开源项目：szechyjs/dsd</p></div>
ALSA backend: Multi ALSA device support2020-11-27 15:39:56<p>This PR contains the following features for the ALSA audio backend - Support multiple devices without using ALSA multi plug-in. Compared to ALSA multi plugin it reduces the CPU load because snd_pcm...
ALSA 配置2021-01-11 23:10:20环境变量： ALSA_CONFIG_PATH_VAR 全局的配置文件路径 ...默认的配置文件：/usr/share/alsa/alsa.conf 预加载的配置文件列表： /usr/etc/alsa/conf.d /etc/alsa/conf.d /etc/asound.conf
Use alsa-rs for alsa support rather than alsa-sys2020-11-23 04:09:20ve made to <code>alsa-rs</code>. I really like it though in principal. It removes almost all unsafe code (certainly the bits that are hard to reason about), and IMO makes the alsa backend much easier ...
ALSA 拓扑2020-08-04 00:03:05ALSA Topology provides a method for audio drivers to load their mixers, routing, PCMs and capabilities from user space at runtime without changing any driver source code. The intention is
ALSA Topology provides a method for audio drivers to load their mixers, routing, PCMs and capabilities from user space at runtime without changing any driver source code. The intention is to write the driver once and do the differentiation in topology.
Why we need topology?
Current audio drivers typically hard code topology information in the driver sources: This tightly couples the audio driver to the development board making it time consuming to modify a driver to work on a different devices. The driver is also tightly coupled to the DSP firmware version meaning extra care is needed to keep the driver and firmware version in sync. New firmware features also mean driver updates.
The ALSA topology project removes the need for re-writing or porting audio drivers to different devices or different firmwares: Drivers have no hard coded topology data meaning a single driver can be used on different devices by updating the topology data from the file system. Firmware updates can be pushed without having to update the drivers. The new firmware just needs to include an updated topology file describing the update.
The topology objects that can be configured by user space include: controls, widgets, routes, PCMs and configurations for physical DAI & DAI links.
Here is an example.
The topology library is part of alsa-lib. Users can define topology objects that describe the topology of a customer firmware, e.g. for an ADSP embedded in SOC or an off-SOC codec. These topology objects can be defined either in a text configuration file or added via C API. And the topology library will parse them and generate a binary file for kernel. Please see the source code in directory src/topology of alsa-lib.
The generated topology binary file consists of a manifest and a list of blocks. The manifest data provides overall info of the topology object types in the file, i.e. number of controls, widgets, routes, PCMs, physical DAI and physical DAI links. Each block consists of a blocker header and a specific type of topology objects. For the layout of file and topology object, please see the ABI file in alsa-lib include/sound/asoc.h and tlv.h
How to generate the topology binary file
Users can define topology objects in a text configuration file. The syntax is based on alsaconf syntax, please see alsa-lib/include/alsa/topology.h Then users can use alsatplg, the topology tool in alsa-utils, to covert the topology text configuration file to the binary, via command "alsatplg -c <path-of-input-text-configuration-file> -o <path-of-output-binary-file>". Please see the alsatplg code in directory topology of alsa-utils, and Intel Broadwell and Skylake configurations in alsa-lib/src/conf/topology as examples of the text configuration file.
Users can also write their own application and call topology library API to add objects and generate the binary file. Please see alsa-lib/include/alsa/topology.h for the API definition.
The topology kernel driver provides API for device drivers to load the topology binary file from the user space, then it will parse the ABI objects in the file, create controls, widgets, routes, front end DAI and DAI links (PCMs) and configure existing physical DAI and DAI links. It will also let the device driver do platform specific initialization on these objects via topology ops registered by the device driver. Please see code of sound/soc/soc-topology.c in kernel.
How device drivers use topology
Intel Skylake platform driver is an example how device drivers use topology, please see code of sound/soc/intel/skylake/skl-topology.c in kernel.
编译ALSA2020-09-27 16:40:29在项目官网上下载alsa-lib和alsa-utils。 2.编译alsa-lib ./configure CC=arm-linux-gcc --host=arm-linux --prefix=$PWD/build --enable-shared --disable-python --with-configdir=$PWD/build/alsa_lib/share -...
./configure CC=arm-linux-gcc --host=arm-linux --prefix=$PWD/build --enable-shared --disable-python --with-configdir=$PWD/build/alsa_lib/share --with-plugindir=$PWD/build/alsa_lib/lib make make install
ALSA tab2020-12-31 03:42:26The controller does not show up in the QjackCtl ALSA tab with setBfree. <p>I dragged the setBfree icon to my text editor. I see the following information: [Desktop Entry] Type=Application Name...
alsa移植2020-05-15 11:14:35alsa-lib-1.2.2.tar.bz2 alsa-utils-1.2.2.tar.bz2 source 交叉工具链 $ source /home/jj/my-work/03_toolchain/gcc-linaro-7.3.1-2018.05-x86_64_aarch64-linux-gnu.env 解压： $ cd ~/my-work/transplant/alsa $ ...
$ source /home/jj/my-work/03_toolchain/gcc-linaro-7.3.1-2018.05-x86_64_aarch64-linux-gnu.env
$ cd ~/my-work/transplant/alsa
$ tar xjvf alsa-lib-1.2.2.tar.bz2
$ tar xjvf alsa-lib-1.2.2.tar.bz2
$ mkdir alsa-lib
$ mkdir alsa-utils
$ cd alsa-lib-1.2.2/
$ ./configure --host=aarch64-linux-gnu --prefix=/home/jj/my-work/transplant/alsa/alsa64/alsa-lib --enable-shared --disable-python
$ make install
$ cd …/alsa-utils-1.2.2/
$ ./configure --host=aarch64-linux-gnu --disable-alsamix
er --disable-xmlto CPPFLAGS=-I/home/jj/my-work/transplant/alsa/alsa64/alsa-lib/include LDFLAGS=-L/home/jj/my-work/transplant/alsa/alsa64/alsa-lib/lib --prefix=/home/jj/my-work/transplant/alsa/alsa64/alsa-utils
$ sudo make install
cp ./alsa-lib/lib/* /usr/lib/ -r
cp ./alsa-utils/bin/* /usr/bin/ -r
cp ./alsa-utils/sbin/* /usr/bin/ -r
chmod +x alsainstall.sh
tar cjvf alsa64-install.tar.bz2 alsa64