Version 3.1 of the Linux kernel was the first release to include regmap support and only included a bare minimum of features in order to ease review so version 3.2 has been a pretty big one for regmap development with some pretty major features being built on top of the core code. Support for register [...]
Linux 3.2 was released yesterday. It’s been a fairly busy release for ASoC in terms of the subsystem, including the first piece of work at moving the register I/O code over to regmap to eliminate the duplication there, but a pretty quiet one on the drivers front. Substantial optimization of the DAPM algorithm, substantially reducing the CPU [...]
Recently I’ve been noticing a surprising pattern in code I’m reviewing for the kernel. A lot of people seem to have taken to writing code that I’d expect to look like this: switch (thing) { case VALUE: /* Stuff */ break; case BAR: /* Nonsense */ break; default: /* Whatever */ break; } with if [...]
A good proportion of I2C and SPI device drivers in the kernel contain some very similar code for accessing the register maps of hardware connected to those buses – most hardware designers have solved the problem of providing very similar ways. Linux 3.1 introduces a new kernel API called regmap which factors out this code [...]
One of the big things that seems to cause a learning curve for many new contributors for Linux and other projects that make a big effort with code review is the process of putting patches together in a way that makes the code review process more smoothly. This is a fairly straightforward thing but it [...]
One slightly unexpected effect of all the travel I’ve been doing recently is that I get a real, visceral sense of place from some slightly surprising places when I see them on the big screen. Having an idea of how the place really is, how people behave, how the air feels, how the food tastes, [...]
Linux 2.6.39 was released earlier today. This release includes a few updates, the main user visible one being that machine drivers can now be registered as regular devices rather than using the soc-audio device. Support for registering machine drivers as first class devices rather than using the soc-audio device. Support for the soc-audio device will [...]
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 [...]
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 [...]
One of the biggest differences between working on most other OSs and working upstream on drivers for the Linux kernel is that elsewhere the core is usually a fixed thing that has been released and can’t really be changed, even if source is available (which may not even be the case). If whatever subsystem you’re [...]