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

[Bard Liao]

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.boss...@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.boss...@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.l...@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovet...@linux.intel.com>
---
 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