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ALSA: hda - Increase default bdl_pos_adj for Baytrail/Braswell
Intel Atom processors seem to have a problem at recording when
bdl_pos_adj is set to an odd value. When a value like 1 is used, it
may drop the samples unexpectedly. Actually, for the old Atoms, we
used to set AZX_DRIVER_SCH type, and this assigns 32 as default.
Meanwhile the newer chips, Baytrail and Braswell, are set as
AZX_DRIVER_PCH, and the lower default value, 1, is assigned.
This patch changes the default values for these chipsets to a safer
default, 32, again. Since changing the driver type (AZX_DRIVER_XXX)
leads to the rename of the driver string, it would result in a
possible regression. So, we can't change the type. Instead, in this
patch, manual (ugly) PCI ID checks are added on top.
A drawback by this increase is the slight increase of the latency, but
it's a sub-ms order in normal situations, so mostly negligible.
Reported-and-tested-by: Jochen Henneberg <jh@henneberg-systemdesign.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>