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 an rbtree or LZO, giving substantial memory savings on CODECs with large register maps, especially those that are sparse. This is especially beneficial to modern devices with integrated DSPs. This can be enabled by machine drivers, though CODECs can also provide defaults.
- Addition of trace points around DAPM and register I/O operation, allowing very low overhead logging without interfering with the main system log, useful for collecting verbose diagnostics without interfering with system operation and for always enabled flight recorder style tracking for intermittent problems. I blogged about ASoC trace points in more detail at the time.
- Restructuring of the Samsung CPU support from Jassi Brar, including a number of really good usability improvements. This supports features of more modern CPUs such as the ability to run two audio streams to a single I2S port and includes a number of API simplifications which should also make developing drivers for Samsung systems much easier.
- New CODEC drivers for ALC5621/2/3, WM8737, WM8770 and WM8958.
- Machine support for HP iPAQ H1940, HP t5325 thin clients and OpenRC Ultimate.