soundwire: bus: improve dynamic debug comments for enumeration

update comments to provide better understanding of enumeration flows.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190806005522.22642-5-pierre-louis.bossart@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/bus.c

@@ -470,7 +470,8 @@ static int sdw_assign_device_num(struct sdw_slave *slave)
 
 	ret = sdw_write(slave, SDW_SCP_DEVNUMBER, dev_num);
 	if (ret < 0) {
-		dev_err(&slave->dev, "Program device_num failed: %d\n", ret);
+		dev_err(&slave->dev, "Program device_num %d failed: %d\n",
+			dev_num, ret);
 		return ret;
 	}
 
@@ -527,6 +528,7 @@ static int sdw_program_device_num(struct sdw_bus *bus)
 	do {
 		ret = sdw_transfer(bus, &msg);
 		if (ret == -ENODATA) { /* end of device id reads */
+			dev_dbg(bus->dev, "No more devices to enumerate\n");
 			ret = 0;
 			break;
 		}
@@ -969,6 +971,7 @@ int sdw_handle_slave_status(struct sdw_bus *bus,
 	int i, ret = 0;
 
 	if (status[0] == SDW_SLAVE_ATTACHED) {
+		dev_dbg(bus->dev, "Slave attached, programming device number\n");
 		ret = sdw_program_device_num(bus);
 		if (ret)
 			dev_err(bus->dev, "Slave attach failed: %d\n", ret);