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Linux Kernel 2.6.31 Released
diegocgteleline.es writes "The Linux kernel v2.6.31 has been released. Besides the desktop improvements and USB 3.0 support mentioned some days ago, there is an equivalent of FUSE for character devices that can be used for proxying OSS sound through ALSA, new tools for using hardware performance counters, readahead improvements, ATI Radeon KMS, Intel's Wireless Multicomm 3200 support, gcov support, a memory checker and a memory leak detector, a reimplementation of inotify and dnotify on top of a new filesystem notification infrastructure, btrfs improvements, support for IEEE 802.15.4, IPv4 over Firewire, new drivers and small improvements. The full list of changes can be found here."
I haven't looked at the official changelog or the code yet, but I'm just as confused as you about that item. Moreso perhaps, as I have used IPv4 over firewire with two linux machines before. That was probably 5 years ago or so.
Not really, the driver people aren't really the same as those who would be researching new and exciting ways to do what we already do. For quite a long time now driver development has been the majority of what the linux kernel development is.
Of course, every now and then they make something new like mac80211, but all that really achieves is more efficient code re-use and testing, which is always good but is still just driver development.
All the simple things an operating system kernel has to do hasn't changed over the last ten or so years, just the hardware has. Operating system theory was pretty much perfected back in the 60's
From the changelog
*The new firewire driver stack is no longer considered experimental, and distributors are encouraged to migrate from the ieee1394 stack to the firewire stack
*Added IP networking to the new FireWire driver stack
It does add up. It's just added to the new stack, old stack has it already.
The fact that, with a modern Linux distro, I can plug in pretty much any hardware at least a year old and have it just work no questions asked is a pretty damn spiffy feature.
So just use ALSA!
The situation on Linux is that there used to be OSS, and now there is ALSA. ALSA works fine, for pretty much everybody. There are a few legacy apps which use OSS because no one is updating them, and obviously, it would be nice if they would play nice. Pulseaudio is a bit strange, but nothing requires it's use, and IMHO there is no real reason for it to be used unless you want to do somewhat strange things (that you generally can't do on any other type of OS). Don't use pulseaudio if you don't want to; if your distro forces it on you, use a sane one.
This scary graph and related ideas tends to get mentioned in connection with this: this conflates libraries, sound servers, and drivers to some extent. One could draw a similar graph for windows, featuring programs using the Quicktime library, the WMP library, MME, DirectSound, WASAPI and various other APIs and libraries (and I haven't even gone into the changes to the audio driver model). WMP would have plenty of in arrows from applications using its libraries, and plenty of out arrows because it supports more than one API. And don't forget that there are still legacy applications which need to be the only app playing audio, just like on Linux.
Here is why I can't be bothered to learn enough about the driver layer to give examples: "UAA is intended to be a complete replacement for developing WDM Audio Drivers; however, in some cases it may be necessary for an otherwise UAA-compliant audio device to expose capabilities that cannot be done through UAA. Windows will continue to fully support audio drivers that use the PortCls and AVStream drivers.
Audio technology has evolved, lots. Having backward compatibility requires that things get slightly complex. Everybody is doing this. I think Linux is doing it rather well, although certain distros make some odd choices.
OSS made it impossible to play more than one stream at once on a lot of hardware.
# cat
Damn, my RAM is full of llamas.
Before we all moved on to worrying about PulseAudio it was traditional for us to complain about legacy apps using OSS, the difficulties associated with wrapping them, the nastiness associated with OSS emulation being implemented in the kernel, etc. Those apps won't have gone away.
Previous attempts to emulate OSS using ALSA have included the aoss tool, which I believe did some mildly ungodly tricks to intercept calls that would usually go to the OSS APIs. It didn't always work, for me, as it depends on what the (often weird and proprietary) app is doing to access the OSS API in the first place. PulseAudio has to provide a tool to help you redirect legacy OSS apps to talk to PulseAudio instead. It's all Made Of Ick.
CUSE (character devices in userspace) allows a userspace program to provide a character device node in /dev and implement it using custom code, rather than relying on an in-kernel driver. When apps open the device node they'll *really* be talking to the userspace daemon implementing the device emulation, rather than to an in-kernel driver (though, of course, the kernel will be involved in relaying the communications through the device interface). This is very similar to what FUSE does for filesystems. The neat thing here is that weird tricks to catch OSS accesses by applications are not needed - the OSS device can simply be "faked" by the real sound daemon. Because it's implemented at device level, it doesn't matter what nasty hacks the OSS application is doing to access the soundcard - you'll *always* be able to grab its sound output from the fake device and do the right thing. No more running legacy apps with an OSS-related wrapper - and no more having the wrapper fail to work!
The end result should be that sound Just Works, even for awkward proprietary apps. CUSE will not automagically fix this on it's own, though - we need to wait for the sound daemons like PulseAudio to catch up and implement the emulation. This might also allow OSS emulation to be removed from the kernel, which AFAIK also supports some variant of OSS-on-ALSA.
I'd argue that drivers should be modular and have no business being directly in the kernel in the first place - but that's just me.
$ find /lib/modules/2.6.27.7-smp/kernel/drivers/ -type f|wc -l
1499
Looks like you're in luck!
You don't need them with OSS on FreeBSD and Solaris (for example), or on Linux with the out-of-tree OSS 4 implementation because they supported sound mixing so the kernel actually does what it is meant to do - lets the userspace apps ignore the differences between hardware implementations. The mixing is either done in hardware if the hardware supports it or software if it doesn't.
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[...] only certain combinations of endpoints can possibly work. You can't plug the host controller of one PC into another, since they're only expecting to talk to devices, not another controller.
Not so with Linux. You can enable the "USB gadget" driver in the kernel. Now if you have a device connector in your system, it can act like any other device. That is how Linux on small devices connects to their hosts via USB. And actually, the way they communicate is plain and simple TCP/IP. :)
Any sufficiently advanced intelligence is indistinguishable from stupidity.
http://btrfs.wiki.kernel.org/index.php/Main_Page has the info, answers, etc
Finally ALSA adds in kernel support for creative X-Fi after 4 years, fuck creative.
There may have been a driver problem years ago, but today the problem is pretty much limited to graphics. And DVB, but the competition is doing just as badly there. Overall, Linux driver support is more complete than at least that of Windows Vista.
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