ALSA: ak4117: Do not free priv until timer handler hasn't actually stopped using it

Function del_timer() does not guarantee that timer was really deleted.
If the timer handler is beeing executed at the moment, the function
does nothing. So, it's possible to use already freed memory in the handler:

[ref: Documentation/DocBook/kernel-locking.tmpl]

This was found using grep and compile-tested only.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
ALSA: hda - Remove dependency on bus->pci in hda_beep.c

The default parent device can be obtained directly via card object, so
we don't need to rely on pci->dev.parent.  Since there is no access to
pci_dev, we can reduce the inclusion of linux/pci.h, too.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
ALSA: hda/realtek - Allow NULL bus->pci

Realtek codec driver contains some codes referring to the PCI
subdevice IDs, but most of them are optional, typically for checking
the codec name variants.  Add NULL checks appropriately so that it can
work without PCI assignment.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
ALSA: hda - Remove superfluous inclusion of linux/pci.h

Some codec drivers still have it since using PCI_VENDOR_ID_*.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
ALSA: usx2y: Don't peep the card internal object

Avoid traversing the device object list of the card instance just for
checking the PCM streams.  The driver's private object already
contains the array of substream pointers, so it can be simply looked
through.  The card internal may be restructured in future, thus better
not to rely on it.

Also, this fixes the possible deadlocks in PCM mutex.  Instead of
taking multiple PCM mutexes, just take the common mutex in all
places.  Along with it, rename prepare_mutex as pcm_mutex.

Signed-off-by: Takashi Iwai <tiwai@suse.de>