After hours of debugging, I finally found the reason why some source
and runtime combination does not work. The PTP (page table pages)
address must be aligned. I am not sure how much, but alignment to
PAGE_SIZE is sufficient. Also, use ALSA's page allocation routines
to ensure proper virtual -> physical address translation.

Cc: <stable@kernel.org>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

- replace NULL == xxx with !xxx
- replace NULL != xxx with xxx
- similar trivial cleanups
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Remove useless variable initializations and cast at the beginning of
functions.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Use SG-buffers instead of contiguous pages.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Remove the limitation of PAGE_SIZE to be 4k by defining the own
page size and macros for 4k.  8kb page size could be natively supported,
but it's disabled right now for simplicity.

Also, clean up using upper_32_bits() macro.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Replace a spinlock with a mutex protecting the vm block list at
mmap / munmap calls, which caused Oops like below:

BUG: sleeping function called from invalid context at mm/slub.c:1599
in_atomic(): 0, irqs_disabled(): 1, pid: 32065, name: xine
Pid: 32065, comm: xine Tainted: P           2.6.29.4-75.fc10.x86_64 #1
Call Trace:
  [<ffffffff81040685>] __might_sleep+0x105/0x10a
  [<ffffffff810c9fae>] kmem_cache_alloc+0x32/0xe2
  [<ffffffffa08e3110>] ct_vm_map+0xfa/0x19e [snd_ctxfi]
  [<ffffffffa08e1a07>] ct_map_audio_buffer+0x4c/0x76 [snd_ctxfi]
  [<ffffffffa08e2aa5>] atc_pcm_playback_prepare+0x1d7/0x2a8 [snd_ctxfi]
  [<ffffffff8105ef3f>] ? up_read+0x9/0xb
  [<ffffffff81186b61>] ? __up_read+0x7c/0x87
  [<ffffffffa08e36a6>] ct_pcm_playback_prepare+0x39/0x60 [snd_ctxfi]
  [<ffffffffa0886bcb>] snd_pcm_do_prepare+0x16/0x28 [snd_pcm]
  [<ffffffffa08867c7>] snd_pcm_action_single+0x2d/0x5b [snd_pcm]
  [<ffffffffa08881f3>] snd_pcm_action_nonatomic+0x52/0x6a [snd_pcm]
  [<ffffffffa088a723>] snd_pcm_common_ioctl1+0x404/0xc79 [snd_pcm]
  [<ffffffff810c52c8>] ? alloc_pages_current+0xb9/0xc2
  [<ffffffff810c9402>] ? new_slab+0x1a5/0x1cb
  [<ffffffff810ab9ea>] ? vma_prio_tree_insert+0x23/0xc1
  [<ffffffffa088b411>] snd_pcm_playback_ioctl1+0x213/0x230 [snd_pcm]
  [<ffffffff810b6c20>] ? mmap_region+0x397/0x4c9
  [<ffffffffa088bd9b>] snd_pcm_playback_ioctl+0x2e/0x36 [snd_pcm]
  [<ffffffff810ddc64>] vfs_ioctl+0x2a/0x78
  [<ffffffff810de130>] do_vfs_ioctl+0x462/0x4a2
  [<ffffffff81029cef>] ? default_spin_lock_flags+0x9/0xe
  [<ffffffff81374647>] ? trace_hardirqs_off_thunk+0x3a/0x6c
  [<ffffffff810de1c5>] sys_ioctl+0x55/0x77
  [<ffffffff8101133a>] system_call_fastpath+0x16/0x1b
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Added ctxfi: prefix to each debug print.
Signed-off-by: Takashi 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: Wai Yew CHAY <wychay@ctl.creative.com>
Singed-off-by: Ryan RICHARDS <ryan_richards@creativelabs.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>