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-rw-r--r--README.md77
-rwxr-xr-xloadDrivers.sh19
2 files changed, 65 insertions, 31 deletions
diff --git a/README.md b/README.md
index 77eb821..d6564fa 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,4 @@
-Alsa Virtual Sound Driver
---------------------------
+## Alsa Virtual Sound Driver
The ALSA Virtual Sound Driver (AVIRT) aims to provide a Linux kernel solution to the issue of audio routing in kernel-space, as well as security per-stream, and dynamic configuration of streams at the kernel level.
@@ -9,45 +8,99 @@ The top-level driver is configured (currently) using module parameters, as is th
A sample dummy Audio Path is provided as an example to show how a low-level audio driver would subscribe to AVIRT, and accept audio routing for playback.
+Currently, the Fiberdyne DSP hardmixer is supported on the Renesas R-Car M3 AGL
+reference platform, and a default loopback softmixer is in development.
+
## Building
+
### Out Of Tree
+
The kernel modules can be built either in-tree, or out-of-tree.
To build both AVIRT and the dummy Audio Path out-of-tree, use the following command:
```sh
-$ CONFIG_AVIRT=m CONFIG_AVIRT_BUILDLOCAL=y CONFIG_AVIRT_DUMMYAP=m make -C /lib/modules/$(uname -r)/build/ M=$(pwd)
+$ make all
```
-To build both AVIRT and the dummy Audio Path out-of-tree for [AGL](http://docs.automotivelinux.org/) (`aarch64` currently supported), use the [XDS](http://docs.automotivelinux.org/docs/devguides/en/dev/reference/xds/part-1/0_Abstract.html) build system together with the `make_agl.sh` script:
+If building for [AGL](http://docs.automotivelinux.org/), use the [XDS](http://docs.automotivelinux.org/docs/devguides/en/dev/reference/xds/part-1/0_Abstract.html) build system together with the `make_agl.sh` script:
```sh
$ ./make_agl.sh ${XDS_SDK_ID}
```
+
### In tree
+
To build in tree, use the [Fiberdyne Linux fork](https://github.com/fiberdyne/linux), which will automatically clone the AVIRT Driver and required AudioPath modules to the `drivers/staging` directory. You can then turn AVIRT Support on by setting to `<M>`. The drivers can be found here:
+
```
$ make menuconfig
# Navigate to: Device Drivers--->Staging Drivers--->AVIRT Support
```
+
Finally build the kernel with the configuration selected by making.
+
```
$ make
```
## Running
-To run, we must load the kernel modules using the `loadDrivers.sh` script, which contains sample module parameters to AVIRT:
+
+Firstly, install the resulting kernel modules to the appropriate modules
+directory, and run`depmod`. For example, in AGL:
+
+```sh
+cp avirt_core.ko avirt_dummyap.ko /lib/modules/4.14.0-yocto-standard/
+depmod
+```
+
+Now we can load the modules:
+
```sh
-$ ./loadDrivers.sh
+modprobe avirt_core
+modprobe avirt_dummyap
```
-To unload the drivers use:
+
+We must now configure AVIRT. We can do this with the test script:
+
+```sh
+source scripts/test_configfs.sh
+```
+
+We can see the newly created streams by using the `aplay` utility. For example:
+
```sh
-$ ./unload.sh
+aplay -l
+...
+card 2: avirt [avirt], device 0: multimedia [multimedia]
+ Subdevices: 1/1
+ Subdevice #0: subdevice #0
+card 2: avirt [avirt], device 1: navigation [navigation]
+ Subdevices: 1/1
+ Subdevice #0: subdevice #0
+card 2: avirt [avirt], device 2: emergency [emergency]
+ Subdevices: 1/1
+ Subdevice #0: subdevice #0
```
+## 4A Integration
+
+AVIRT has been integrated with [4a-softmixer](https://github.com/iotbzh/4a-softmixer)
+and [4a-hal-generic](https://github.com/iotbzh/4a-hal-generic) to provide a smooth
+transition from the existing aloop implementation to the future AVIRT loopback implementation.
+
+### User-space Library
+
+The user-space library [libavirt](https://github.com/fiberdyne/libavirt) can be used to configure AVIRT from within a given AGL 4A binding.
+
+### Hardmixer
+
+A new 4A mixer binding has been developed to demonstrate the capabilities of the
+Fiberdyne DSP mixer operating on the HiFi2 core on-board the Renesas R-Car M3 M3ULCB
+AGL reference platform. This is called the 'hardmixer', and is a faster, lower
+latency alternative to the softmixer.
+
## TODO
- - Currently, playback only - implementing capture is WIP.
- - Rework module parameters into configfs configuration.
- - Create a loopback Audio Path for use with AVIRT, to demonstrate standard AGL soft-mixing capabilities.
- - Modify Fiberdyne DSP driver for use with AVRIT, to demonstrate DSP off-loading and hard-mixing capabilities via Xtensa HiFi2.
+- Currently, playback only - implementing capture is WIP.
+- Create a loopback Audio Path for use with AVIRT, to demonstrate standard AGL soft-mixing capabilities.
diff --git a/loadDrivers.sh b/loadDrivers.sh
deleted file mode 100755
index 9ff5960..0000000
--- a/loadDrivers.sh
+++ /dev/null
@@ -1,19 +0,0 @@
-#!/bin/bash
-
-# Sample module parameters
-params="\
-playback_num=4 \
-playback_chans=2,4,1,1 \
-playback_names=radio,media,nav,phone \
-capture_num=1 \
-capture_chans=2 \
-capture_names=voice"
-
-# Load the virtual driver
-insmod avirt_core.ko "$params"
-
-# Load the additional audio path
-#insmod dummy/avirt_dummyap.ko
-insmod loopback/avirt_loopbackap.ko
-
-echo "Drivers Loaded!"