The MPC5200 AC97 driver is disabling the slots when a stop
trigger is received, but not reenabling them if the stream
is started again without processing the hw_params again.

This patch fixes the problem by caching the slot enable bit
settings calculated at hw_params time so that they can be
reapplied every time the start trigger is received.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NLiam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

Reset was failing with the original udelay(50) between the code in
psc_ac97_cold_reset() and the call to psc_ac97_warm_reset(). Through testing
it was found that a delay of 1ms was necessary for the cold_reset code to
consistently complete successfully.
Signed-off-by: NJohn Bonesio <bones@secretlab.ca>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

AC97 bus register read/write hooks need to provide locking, but the
mpc5200-psc-ac97 driver does not.  This patch adds a mutex around
the register access routines.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NJon Smirl <jonsmirl@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

When doing register reads, it is possible for there to be a stale
data ready bit set which will cause subsequent reads to return
prematurely with incorrect data.  This patch fixes the issues by
ensuring stale data is cleared before starting another transaction.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NJon Smirl <jonsmirl@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

The function signature for spin_event_timeout() has changed in version V9.
Adjust the mpc5200 AC97 driver to use the new function.
Signed-off-by: NJon Smirl <jonsmirl@gmail.com>
Acked-by: NTimur Tabi <timur@freescale.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

I've implemented retries for when the AC97 hardware doesn't reset on
first try. About 10% of the time both the Efika and pcm030 AC97 codecs
don't reset on first try and need to be poked multiple times.  Failure
is indicated by not having the link clock start ticking. Every once in
a while even five pokes won't get the link started and I have to power
cycle.
Signed-off-by: NJon Smirl <jonsmirl@gmail.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>