soundwire: intel: move bank switch routine to common intel_bus_common.c

No functionality change, just moving the routines to a common file so
that they can be used for new hardware.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20230314015410.487311-11-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 49 insertions, 0 deletions

diff --git a/drivers/soundwire/intel_bus_common.c b/drivers/soundwire/intel_bus_common.c
index 9a06ab58018b..f180e3bea989 100644
--- a/drivers/soundwire/intel_bus_common.c
+++ b/drivers/soundwire/intel_bus_common.c
@@ -208,3 +208,52 @@ int intel_stop_bus(struct sdw_intel *sdw, bool clock_stop)
 
 	return 0;
 }
+
+/*
+ * bank switch routines
+ */
+
+int intel_pre_bank_switch(struct sdw_intel *sdw)
+{
+	struct sdw_cdns *cdns = &sdw->cdns;
+	struct sdw_bus *bus = &cdns->bus;
+
+	/* Write to register only for multi-link */
+	if (!bus->multi_link)
+		return 0;
+
+	sdw_intel_sync_arm(sdw);
+
+	return 0;
+}
+
+int intel_post_bank_switch(struct sdw_intel *sdw)
+{
+	struct sdw_cdns *cdns = &sdw->cdns;
+	struct sdw_bus *bus = &cdns->bus;
+	int ret = 0;
+
+	/* Write to register only for multi-link */
+	if (!bus->multi_link)
+		return 0;
+
+	mutex_lock(sdw->link_res->shim_lock);
+
+	/*
+	 * post_bank_switch() ops is called from the bus in loop for
+	 * all the Masters in the steam with the expectation that
+	 * we trigger the bankswitch for the only first Master in the list
+	 * and do nothing for the other Masters
+	 *
+	 * So, set the SYNCGO bit only if CMDSYNC bit is set for any Master.
+	 */
+	if (sdw_intel_sync_check_cmdsync_unlocked(sdw))
+		ret = sdw_intel_sync_go_unlocked(sdw);
+
+	mutex_unlock(sdw->link_res->shim_lock);
+
+	if (ret < 0)
+		dev_err(sdw->cdns.dev, "Post bank switch failed: %d\n", ret);
+
+	return ret;
+}