These helpers configure the ratio between the base clock and the
hardware signal used for link synchronization.

The SYNCPRD is written before the first sublink is powered-up. The
SYNCPU bit is set, but it will only be cleared after the link is
powered-up, hence the implementation with a set/wait pattern.

These helpers are currently only needed by SoundWire support, where
the lock is taken at a higher level, so only the _unlocked versions
are exposed for now.

Note that the _wait_bit() implementation is similar to previous
helpers in drivers/soundwire, but with sleep duration and timeout
aligned with hardware recommendations. If desired, this helper could
be modified in a second step with e.g. readl_poll_timeout().
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20230404104127.5629-13-peter.ujfalusi@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>