soundwire: intel: add missing support for all clock stop modes

Deal with the BUS_RESET case, which is the default. The only change is
to add support for the exit sequence using the syncArm/syncGo mode for
the exit reset sequence.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200901150556.19432-5-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/intel.c

@@ -1868,11 +1868,6 @@ static int intel_resume_runtime(struct device *dev)
 
 		if (!clock_stop0) {
 
-			/*
-			 * Re-initialize the IP since it was powered-off
-			 */
-			sdw_cdns_init(&sdw->cdns);
-
 			/*
 			 * make sure all Slaves are tagged as UNATTACHED and
 			 * provide reason for reinitialization
@@ -1880,13 +1875,31 @@ static int intel_resume_runtime(struct device *dev)
 
 			status = SDW_UNATTACH_REQUEST_MASTER_RESET;
 			sdw_clear_slave_status(bus, status);
-		}
 
+			ret = sdw_cdns_enable_interrupt(cdns, true);
+			if (ret < 0) {
+				dev_err(dev, "cannot enable interrupts during resume\n");
+				return ret;
+			}
+
+			/*
+			 * follow recommended programming flows to avoid
+			 * timeouts when gsync is enabled
+			 */
+			if (multi_link)
+				intel_shim_sync_arm(sdw);
 
-		ret = sdw_cdns_enable_interrupt(cdns, true);
-		if (ret < 0) {
-			dev_err(dev, "cannot enable interrupts during resume\n");
-			return ret;
+			/*
+			 * Re-initialize the IP since it was powered-off
+			 */
+			sdw_cdns_init(&sdw->cdns);
+
+		} else {
+			ret = sdw_cdns_enable_interrupt(cdns, true);
+			if (ret < 0) {
+				dev_err(dev, "cannot enable interrupts during resume\n");
+				return ret;
+			}
 		}
 
 		ret = sdw_cdns_clock_restart(cdns, !clock_stop0);
@@ -1894,6 +1907,22 @@ static int intel_resume_runtime(struct device *dev)
 			dev_err(dev, "unable to restart clock during resume\n");
 			return ret;
 		}
+
+		if (!clock_stop0) {
+			ret = sdw_cdns_exit_reset(cdns);
+			if (ret < 0) {
+				dev_err(dev, "unable to exit bus reset sequence during resume\n");
+				return ret;
+			}
+
+			if (multi_link) {
+				ret = intel_shim_sync_go(sdw);
+				if (ret < 0) {
+					dev_err(sdw->cdns.dev, "sync go failed during resume\n");
+					return ret;
+				}
+			}
+		}
 	} else if (!clock_stop_quirks) {
 		ret = intel_init(sdw);
 		if (ret) {