ASoC: SOF: Intel: hda-mlink: add helpers to set link SYNC frequency

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.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/include/sound/hda-mlink.h b/include/sound/hda-mlink.h
index 872652209a47..80af2a3996d7 100644
--- a/include/sound/hda-mlink.h
+++ b/include/sound/hda-mlink.h
@@ -17,6 +17,12 @@ int hdac_bus_eml_get_count(struct hdac_bus *bus, bool alt, int elid);
 void hdac_bus_eml_enable_interrupt(struct hdac_bus *bus, bool alt, int elid, bool enable);
 bool hdac_bus_eml_check_interrupt(struct hdac_bus *bus, bool alt, int elid);
 
+int hdac_bus_eml_set_syncprd_unlocked(struct hdac_bus *bus, bool alt, int elid, u32 syncprd);
+int hdac_bus_eml_sdw_set_syncprd_unlocked(struct hdac_bus *bus, u32 syncprd);
+
+int hdac_bus_eml_wait_syncpu_unlocked(struct hdac_bus *bus, bool alt, int elid);
+int hdac_bus_eml_sdw_wait_syncpu_unlocked(struct hdac_bus *bus);
+
 int hdac_bus_eml_power_up(struct hdac_bus *bus, bool alt, int elid, int sublink);
 int hdac_bus_eml_power_up_unlocked(struct hdac_bus *bus, bool alt, int elid, int sublink);
 
@@ -48,6 +54,27 @@ static inline bool
 hdac_bus_eml_check_interrupt(struct hdac_bus *bus, bool alt, int elid) { return false; }
 
 static inline int
+hdac_bus_eml_set_syncprd_unlocked(struct hdac_bus *bus, bool alt, int elid, u32 syncprd)
+{
+	return 0;
+}
+
+static inline int
+hdac_bus_eml_sdw_set_syncprd_unlocked(struct hdac_bus *bus, u32 syncprd)
+{
+	return 0;
+}
+
+static inline int
+hdac_bus_eml_wait_syncpu_unlocked(struct hdac_bus *bus, bool alt, int elid)
+{
+	return 0;
+}
+
+static inline int
+hdac_bus_eml_sdw_wait_syncpu_unlocked(struct hdac_bus *bus) { return 0; }
+
+static inline int
 hdac_bus_eml_power_up(struct hdac_bus *bus, bool alt, int elid, int sublink)
 {
 	return 0;