ASoC conference 2011 – Edinburgh, 4-5th May

There will be an ASoC conference in Edinburgh 4th-5th May this year, held in the Scotch Malt Whisky Society in Edinburgh. Full details are in the announcement – if you’ve got an interest in embedded audio on Linux I recommend you attend, there’s a lot of development going on in this area right now and […]

ASoC updates in 2.6.38

Linux 2.6.38 was just released, with another big update to ASoC including: Enhancements to multi-component from Jarkko Nikula allowing multiple devices of the same type to be included in one system (and handling other overlaps between devices) and support cross device DAPM. Support from Dimitris Papastamos for compressing the register cache in memory using either […]

Tracing ASoC with trace events

Kernel 2.6.38 will add support for tracing ASoC using trace points. Previously all logging for ASoC had been done using printk(), meaning that changing the active logging required a kernel rebuild and that when trace was enabled the volume of trace could easily become very disruptive to other logging within the system. Trace points solve these […]

ASoC changes in 2.6.37

2.6.37, which was released today, has been a very big release for ASoC – about 40,000 lines of changes covering every single file within the subsystem plus a bunch of new drivers. The highlights are: Overhaul of the core APIs for registration of all kinds of devices from my co-maintainer Liam Girdwood, reducing the level of […]

ASoC updates in 2.6.35

Linux 2.6.35 has been a fairly interesting release from an ASoC point of view, with several notable framework enhancements: Support for keeping audio paths through the CODEC up during system suspend, primarily intended for use with devices where the Linux system is one of several independent systems running on the device and the other systems […]

ASoC updates in 2.6.34

Linux 2.6.34 was released today. This contains a fairly substantial batch of ASoC updates, including: Support for turning CODEC biases off completely when idle, providing power savings for modern devices with ground referenced outputs where this can be done quickly at runtime without pops and clicks. Support for disabling physical writes to the device in […]

ASoC updates in 2.6.33

This has been another fairly quiet release for ASoC.  Aside from the addition of virtual mux support to DAPM and some further preparatory work for multi-CODEC cards the majority of changes have been driver updates, including: New CODEC drivers for ADS117x, AK4671, TLV320DAC33, TPA6130A2, WM8711 and WM8727. Support for the PCM port on Samsung SoCs. Substantial improvements to […]

ASoC updates in 2.6.32

Linux 2.6.32 was released overnight. This has been a fairly busy release for ASoC, with changes including: Redone power sequencing code, giving shorter power sequences which should reduce the effect of any artifacts that exist. Reporting of power management decisions via debugfs, enabling much easier diagnosis of path setup problems. Beginning of work to factor […]

ASoC updates in 2.6.31

Linux 2.6.31 was released today. This was a fairly busy release for the ASoC subsystem, with updates including: DAPM supply widget, for automatically managing things like charge pumps and gateable clocks which may be used by more than one widget. Core support for setting up constraints for symmetric sample rates (for systems with a shared […]

In-kernel audio mixing

Ever since PulseAudio started to be deployed by distributions the most common complaint I’ve seen about ALSA is that unlike current versions of OSS it doesn’t provide mixing of audio from multiple applications inside the kernel. Of course what it really comes down to is that people want the system to transparently allow multiple applications […]