SoundWire: improve bus reset

[plbossart]

Tentative PR to check CI results on multiple generations of hardware. Tested successfully with MODEL=TGLU_SKU0A32_SDCA

[rfvirgil]

Tested on TigerLake UpXtreme + 4 x CS35L56 (EIGHT-C/AIC1.0).When exiting clock stop there's some initial bus activity which is too short for the analyzer to decode, but I assume it is PINGs. Then a full bus-reset and CS35L56 audio is working.
This isn't a stress test, but I've repeated this manually several times and I see a bus-reset on every exit from clock-stop.

[plbossart]

Thanks @rfvirgil for testing, I'll do more testing on my end when our CI is back in gear. Happy Friday!

[plbossart]

SOFCI TEST

[RanderWang]

LGTM

[plbossart]

v2 added, the main change is the addition of a wait in exit_reset

v2.diff.txt

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index 9ca600f1fa19..eb1b87ad1681 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -456,9 +456,9 @@ static int cdns_parity_error_injection(void *data, u64 value)
 			CDNS_IP_MCP_CMDCTRL_INSERT_PARITY_ERR);
 
 	/* commit changes */
-	cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE,
-		     CDNS_MCP_CONFIG_UPDATE_BIT,
-		     CDNS_MCP_CONFIG_UPDATE_BIT);
+	ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE, CDNS_MCP_CONFIG_UPDATE_BIT);
+	if (ret < 0)
+		goto unlock;
 
 	/* do a broadcast dummy read to avoid bus clashes */
 	ret = sdw_bread_no_pm_unlocked(&cdns->bus, 0xf, SDW_SCP_DEVID_0);
@@ -470,16 +470,17 @@ static int cdns_parity_error_injection(void *data, u64 value)
 			0);
 
 	/* commit changes */
-	cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE,
-		     CDNS_MCP_CONFIG_UPDATE_BIT,
-		     CDNS_MCP_CONFIG_UPDATE_BIT);
-
-	/* Continue bus operation with parity error injection disabled */
-	mutex_unlock(&bus->bus_lock);
+	ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE, CDNS_MCP_CONFIG_UPDATE_BIT);
+	if (ret < 0)
+		goto unlock;
 
 	/* Userspace changed the hardware state behind the kernel's back */
 	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
 
+unlock:
+	/* Continue bus operation with parity error injection disabled */
+	mutex_unlock(&bus->bus_lock);
+
 	/*
 	 * allow Master device to enter pm_runtime suspend. This may
 	 * also result in Slave devices suspending.
@@ -1139,13 +1140,7 @@ int sdw_cdns_exit_reset(struct sdw_cdns *cdns)
 		     CDNS_MCP_CONTROL_HW_RST);
 
 	/* commit changes */
-	cdns_updatel(cdns, CDNS_MCP_CONFIG_UPDATE,
-		     CDNS_MCP_CONFIG_UPDATE_BIT,
-		     CDNS_MCP_CONFIG_UPDATE_BIT);
-
-	/* don't wait here */
-	return 0;
-
+	return cdns_config_update(cdns);
 }
 EXPORT_SYMBOL(sdw_cdns_exit_reset);
 
diff --git a/drivers/soundwire/intel_bus_common.c b/drivers/soundwire/intel_bus_common.c
index be0c93106fc8..e5ac3cc7cb79 100644
--- a/drivers/soundwire/intel_bus_common.c
+++ b/drivers/soundwire/intel_bus_common.c
@@ -182,8 +182,7 @@ int intel_start_bus_after_clock_stop(struct sdw_intel *sdw)
 		return ret;
 	}
 
-	sdw_cdns_check_self_clearing_bits(cdns, "intel_resume_runtime no_quirks",
-					  true, INTEL_MASTER_RESET_ITERATIONS);
+	sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS);
 
 	return 0;
 }