Add maximum latency tracking to the ALSA subsystem for PCM playback. In
ALSA, the playback application controls the buffer size and thus indirectly
the period of latency that it can deal with. This patch uses 75% of the
total available latency as threshold to announce to the latency subsystem;
While 75% is a crude heuristic it's a quite reasonable one; the remaining
25% can be used for all driver processing for the next samples which is
also proportional to the size of the buffer.
With ogg123 a latency setting of about 4msec was seen (at 44Khz), while
with the "play" command a much longer maximum tolerable latency was seen.
Other, more multimedia oriented players as well as games, will have a lot
smaller buffers to allow better synchronization and those will actually get
into the latency domains where there is impact on the power management
rules.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds a new attribute, pcm_class, to each PCM sysfs entry.
It's useful to detect what kind of PCM stream is, for example, HAL
can check whether it's a modem or not.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
The PCM and rawmidi substreams can be selected explicitly by opening
control handle and set via *_PREFER_SUBDEVICE ioctl. But, when
multiple controls are opened, the driver gets confused.
The patch fixes the initialization of prefer_*_subdevice and the
check of multiple controls. The first set subdevice is picked up
as the valid one.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
Orignally proposed by Sam Revitch <sam.revitch@gmail.com>.
Unregister device files at disconnection to avoid the futher accesses.
Also, the dev_unregister callback is removed and replaced with the
combination of disconnect + free.
A new function snd_card_free_when_closed() is introduced, which is
used in USB disconnect callback.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
- Add the linked list to each proc entry to enable a single-shot
disconnection (unregister)
- Deprecate snd_info_unregister(), use snd_info_free_entry()
- Removed NULL checks of snd_info_free_entry()
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
Move mmap_count to snd_pcm_substream instead of runtime struct
so that multiplly opened substreams via O_APPEND can be handled
correctly.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Added O_APPEND flag support to PCM to enable shared substreams
among multiple processes. This mechanism is used by dmix and
dsnoop plugins.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Move EXPORT_SYMBOL()s to places adjacent to functions/variables.
Also move OSS-specific hw_params helper functions to pcm_oss.c.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Fixed Oops at rmmod with CONFIG_SND_VERBOSE_PROCFS=n.
Add ifdef to struct fields for optimization and better compile
checks.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Modules: PCM Midlevel
This patch makes the needlessly global snd_pcm_format_name() static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
- Clean up initialization and destruction of substream instance
Now snd_pcm_open_substream() alone does most initialization jobs.
Add pcm_release callback for cleaning up at snd_pcm_release_substream()
- Tidy up PCM oss code
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Modules: PCM Midlevel,USB generic driver
Because snd_pcm_format_name() function is used only for informational
purposes, it is no longer exported from the PCM midlevel to reduce
space and dependency. usbaudio module shows only numeric value for format.
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Modules: ALSA Core,PCM Midlevel,ALSA<-OSS emulation,USB generic driver
1) The verbose procfs code for the PCM midlevel and usb audio
can be removed now (more patches will follow).
CONFIG_SND_VERBOSE_PROCFS
2) The PCM OSS plugin system can be also compiled optionaly.
CONFIG_SND_PCM_OSS_PLUGINS
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
Instead of storing the pointers to the device-specific structures in an
array, put them into the struct snd_minor, and look them up dynamically.
This makes the device type modules independent of the minor number
encoding.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Instead of a comment string, store the device type in the snd_minor
structure. This makes snd_minor more flexible, and has the nice side
effect that we don't need anymore to create a separate snd_minor
template for registering a device but can pass the file_operations
directly to snd_register_device().
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Remove snd_runtime_check() macro.
This macro worsens the readability of codes. They should be either
normal if() or removable asserts.
Also, the assert displays stack-dump, instead of only the last caller
pointer.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
PCM Midlevel,ALSA Core,Timer Midlevel,ALSA sequencer,Virtual Midi
This patch contains the following possible cleanups:
- make needlessly global code static
- #if 0 the following unused global functions
- remove the following unneeded EXPORT_SYMBOL's
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
PCM Midlevel
Export snd_pcm_format_size(). This function is used by some out-of-kernel
drivers.
Make snd_pcm_format_cpu_endian() macro for optimization.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
PCM Midlevel,CA0106 driver,EMU10K1/EMU10K2 driver
Fix by Guillaume Chazarain <guichaz@yahoo.fr>:
Some tunables in /proc have a write() function, but as their
permission does not reflect it, it can be confusing to the user.
So here is a patch that corrects the mode of those files. Note that I
have only tested the 'xrun_debug' entry.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
