[PATCH v2 1/9] soundwire: bus: use sdw_update_no_pm when initializing a device

[Bard Liao]

From: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>

When a Slave device is resumed, it may resume the bus and restart the
enumeration. During that process, we absolutely don't want to call
regular read/write routines which will wait for the resume to
complete, otherwise a deadlock occurs.

Fixes: 60ee9be25571 ('soundwire: bus: add PM/no-PM versions of read/write functions')
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
Reviewed-by: Rander Wang <rander.wang at linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao at linux.intel.com>
---
 drivers/soundwire/bus.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index d1e8c3a54976..60c42508c6c6 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -489,6 +489,18 @@ sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
 		return buf;
 }
 
+static int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
+{
+	int tmp;
+
+	tmp = sdw_read_no_pm(slave, addr);
+	if (tmp < 0)
+		return tmp;
+
+	tmp = (tmp & ~mask) | val;
+	return sdw_write_no_pm(slave, addr, tmp);
+}
+
 /**
  * sdw_nread() - Read "n" contiguous SDW Slave registers
  * @slave: SDW Slave
@@ -1256,7 +1268,7 @@ static int sdw_initialize_slave(struct sdw_slave *slave)
 	val = slave->prop.scp_int1_mask;
 
 	/* Enable SCP interrupts */
-	ret = sdw_update(slave, SDW_SCP_INTMASK1, val, val);
+	ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
 	if (ret < 0) {
 		dev_err(slave->bus->dev,
 			"SDW_SCP_INTMASK1 write failed:%d\n", ret);
@@ -1271,7 +1283,7 @@ static int sdw_initialize_slave(struct sdw_slave *slave)
 	val = prop->dp0_prop->imp_def_interrupts;
 	val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
 
-	ret = sdw_update(slave, SDW_DP0_INTMASK, val, val);
+	ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
 	if (ret < 0)
 		dev_err(slave->bus->dev,
 			"SDW_DP0_INTMASK read failed:%d\n", ret);
-- 
2.17.1