[PATCH v2 2/3] soundwire: bus: handle master quirks for bus clash and parity

[Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>]

Add optional interrupt status read/clear if the master quirks are set.

In the case of the parity, the master quirk is only applied if the
Slave doesn't already have a parity-related quirk.

Co-developed-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxxxxxxxx>
---
 drivers/soundwire/bus.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index 46885429928a..04eb879de145 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -1253,6 +1253,7 @@ static int sdw_slave_set_frequency(struct sdw_slave *slave)
 static int sdw_initialize_slave(struct sdw_slave *slave)
 {
 	struct sdw_slave_prop *prop = &slave->prop;
+	int status;
 	int ret;
 	u8 val;
 
@@ -1260,6 +1261,44 @@ static int sdw_initialize_slave(struct sdw_slave *slave)
 	if (ret < 0)
 		return ret;
 
+	if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
+		/* Clear bus clash interrupt before enabling interrupt mask */
+		status = sdw_read_no_pm(slave, SDW_SCP_INT1);
+		if (status < 0) {
+			dev_err(&slave->dev,
+				"SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
+			return status;
+		}
+		if (status & SDW_SCP_INT1_BUS_CLASH) {
+			dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
+			ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
+			if (ret < 0) {
+				dev_err(&slave->dev,
+					"SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
+				return ret;
+			}
+		}
+	}
+	if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
+	    !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
+		/* Clear parity interrupt before enabling interrupt mask */
+		status = sdw_read_no_pm(slave, SDW_SCP_INT1);
+		if (status < 0) {
+			dev_err(&slave->dev,
+				"SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
+			return status;
+		}
+		if (status & SDW_SCP_INT1_PARITY) {
+			dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
+			ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
+			if (ret < 0) {
+				dev_err(&slave->dev,
+					"SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
+				return ret;
+			}
+		}
+	}
+
 	/*
 	 * Set SCP_INT1_MASK register, typically bus clash and
 	 * implementation-defined interrupt mask. The Parity detection
-- 
2.17.1