Difference between revisions of "CS4299"
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=== CS4299 === | === CS4299 === | ||
− | This is a Cirrus Logic AC'97 Audio | + | This is a Cirrus Logic AC'97 Audio codec |
This chip is sometimes incorrectly called CS4229 in IBM documentation | This chip is sometimes incorrectly called CS4229 in IBM documentation | ||
+ | |||
=== Features === | === Features === | ||
* Chipset: CS4299 | * Chipset: CS4299 | ||
Line 13: | Line 14: | ||
|style="vertical-align:top" | | |style="vertical-align:top" | | ||
|} | |} | ||
+ | === Linux ALSA driver === | ||
+ | This sound chip is supported by the snd-intel8x0 kernel module. | ||
+ | |||
+ | === T23 Fast Sound === | ||
+ | On at least one t23 (mine) the ALSA intel8x0 driver plays sound too fast. The following {{path|/etc/asound.conf}} restores normal operation: | ||
− | + | pcm.intel8x0-hw { | |
− | + | type hw | |
+ | card 0 | ||
+ | } | ||
+ | |||
+ | pcm.!default { | ||
+ | type plug | ||
+ | slave.pcm "intel8x0" | ||
+ | } | ||
+ | |||
+ | pcm.intel8x0 { | ||
+ | type dmix | ||
+ | ipc_key 1234 | ||
+ | slave { | ||
+ | pcm "hw:0,0" | ||
+ | period_time 0 | ||
+ | period_size 512 | ||
+ | buffer_size 4096 | ||
+ | rate 44100 | ||
+ | } | ||
+ | } | ||
+ | |||
+ | ctl.intel8x0-hw { | ||
+ | type hw | ||
+ | card 0 | ||
+ | } | ||
− | |||
− | |||
− | + | === Dmixing === | |
The CS4299 is not capable of hardware mixing. This means that only one sound stream can be played at any time. | The CS4299 is not capable of hardware mixing. This means that only one sound stream can be played at any time. | ||
You must get the software to do the mixing for it (this will load your CPU). | You must get the software to do the mixing for it (this will load your CPU). | ||
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} | } | ||
− | Now the only problem is how to tell applications to use the DMIX channel instead of dsp0. | + | Now the only problem is how to tell applications to use the DMIX channel instead of dsp0. Most applications work by specifying "dmix" as the device. For command line apps use "aoss". |
+ | |||
+ | Hint: XMMS does not work well with dmix and the intel8x0. You will probably need to patch and recompile. | ||
+ | |||
+ | See: [http://bugs.xmms.org/show_bug.cgi?id=1716 XMMS bug 1716], [http://bugs.xmms.org/show_bug.cgi?id=2009 XMMS bug 2009] and [http://bugs.xmms.org/show_bug.cgi?id=1991 XMMS bug 1991] | ||
+ | |||
+ | You also need to disable mmap and increase the buffer and period time in the advanced options. | ||
+ | |||
+ | === No sound after suspending to RAM === | ||
+ | Fortunately it is not necessary to remove and reinsert the snd-intel8x0 module. Simply mute and unmute all the mixer controls using alsamixer or amixer. You might want to create the following script and run it after your suspend commands: | ||
+ | #!/bin/bash | ||
+ | mixers="Master PCM CD" | ||
+ | for mixer in $mixers ; do | ||
+ | amixer sset $mixer mute | ||
+ | amixer sset $mixer unmute | ||
+ | done | ||
+ | |||
+ | Other mixers you might want to add are Line (Line in on the laptop) and Aux (Line in on the docking station). | ||
+ | Note that the case of the mixer names is important ("Master" not "master"). | ||
=== ThinkPads this chip may be found in === | === ThinkPads this chip may be found in === | ||
Line 48: | Line 94: | ||
* {{i1300}}, {{i1330}}, {{i1370}} | * {{i1300}}, {{i1330}}, {{i1370}} | ||
− | [[Category: | + | [[Category:Audio Devices]] |
Latest revision as of 14:20, 15 November 2020
CS4299This is a Cirrus Logic AC'97 Audio codec This chip is sometimes incorrectly called CS4229 in IBM documentation Features
|
Linux ALSA driver
This sound chip is supported by the snd-intel8x0 kernel module.
T23 Fast Sound
On at least one t23 (mine) the ALSA intel8x0 driver plays sound too fast. The following /etc/asound.conf restores normal operation:
pcm.intel8x0-hw { type hw card 0 } pcm.!default { type plug slave.pcm "intel8x0" } pcm.intel8x0 { type dmix ipc_key 1234 slave { pcm "hw:0,0" period_time 0 period_size 512 buffer_size 4096 rate 44100 } } ctl.intel8x0-hw { type hw card 0 }
Dmixing
The CS4299 is not capable of hardware mixing. This means that only one sound stream can be played at any time. You must get the software to do the mixing for it (this will load your CPU). The ALSA implementation of this is called DMIX. You can also run sound servers like ESD or ArtsD, but not all applications will use them. Recent ALSA distributions have dmixing setup and enabled by default.
Otherwise just add the following to /etc/asound.conf :
pcm.dsp0 { type plug slave.pcm dmix } # mixer0 can stay unchanged, because # it isn't used anyway, I guess ;) ctl.mixer0 { type hw card 0 }
Now the only problem is how to tell applications to use the DMIX channel instead of dsp0. Most applications work by specifying "dmix" as the device. For command line apps use "aoss".
Hint: XMMS does not work well with dmix and the intel8x0. You will probably need to patch and recompile.
See: XMMS bug 1716, XMMS bug 2009 and XMMS bug 1991
You also need to disable mmap and increase the buffer and period time in the advanced options.
No sound after suspending to RAM
Fortunately it is not necessary to remove and reinsert the snd-intel8x0 module. Simply mute and unmute all the mixer controls using alsamixer or amixer. You might want to create the following script and run it after your suspend commands:
#!/bin/bash mixers="Master PCM CD" for mixer in $mixers ; do amixer sset $mixer mute amixer sset $mixer unmute done
Other mixers you might want to add are Line (Line in on the laptop) and Aux (Line in on the docking station). Note that the case of the mixer names is important ("Master" not "master").