Allow unknown PCI SSIDs for emu20k1 and emu20k2 as "unknown" model.
Also, add a black-list check in case any device has to be listed
as "unsupported".  It has a negative value in the pci quirk entry.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Clean up probe routines and model detection routines so that the driver
won't call and check the PCI subsystem id at each time.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Optimize the timer update routine to look up wall clock once instead of
checking the position of each stream at each timer update.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

emu20k1 has a native timer interrupt based on the audio clock, which
is more accurate than the system timer (from the synchronization POV).
This patch adds the code to handle this with multiple streams.

The system timer is still used on emu20k2, and can be used also for
emu20k1 easily by changing USE_SYSTEM_TIMER to 1 in cttimer.c.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The Sound Blaster X-Fi driver supports Creative solutions based on
20K1 and 20K2 chipsets.

Supported hardware :

Creative Sound Blaster X-Fi Titanium Fatal1ty® Champion Series
Creative Sound Blaster X-Fi Titanium Fatal1ty Professional Series
Creative Sound Blaster X-Fi Titanium Professional Audio
Creative Sound Blaster X-Fi Titanium
Creative Sound Blaster X-Fi Elite Pro
Creative Sound Blaster X-Fi Platinum
Creative Sound Blaster X-Fi Fatal1ty
Creative Sound Blaster X-Fi XtremeGamer
Creative Sound Blaster X-Fi XtremeMusic

Current release features:

* ALSA PCM Playback
* ALSA Record
* ALSA Mixer

Note:

* External I/O modules detection not included.
Signed-off-by: NWai Yew CHAY <wychay@ctl.creative.com>
Singed-off-by: NRyan RICHARDS <ryan_richards@creativelabs.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>