diff options
| author | Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> | 2020-01-14 18:08:37 -0600 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2020-02-25 15:57:02 +0530 |
| commit | a90def0681270eb58496825b8861aa9ffca6abce (patch) | |
| tree | 47fa647d65057324917b5aa65f23a6749d7d720d /drivers/soundwire | |
| parent | fb9469e54fa7a7b6a8137c40ae66c41b8d0ab175 (diff) | |
soundwire: bus: fix race condition with initialization_complete signaling
Waiting for the enumeration to be complete may not be enough for a
Slave driver, there is a possible race condition between resume
operations and initializations handled in an interrupt thread, which
can results in settings not being fully restored after system or
pm_runtime resume.
This patch builds on the changes added for enumeration_complete,
init_completion() is called when the Slave device becomes UNATTACHED,
as done with enumeration_complete.
The difference with the enumeration_complete case is that complete()
is signaled after the Slave device is fully initialized after the
.update_status() callback is called.
A Slave device driver can decide to wait on either of the two
complete() cases, depending on its initialization code and
requirements.
Signed-off-by: Rander Wang <rander.wang@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200115000844.14695-4-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/soundwire')
| -rw-r--r-- | drivers/soundwire/bus.c | 8 | ||||
| -rw-r--r-- | drivers/soundwire/slave.c | 1 |
2 files changed, 9 insertions, 0 deletions
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index a2267c3a1d2d..ea04cf5f5bdc 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -621,6 +621,7 @@ static void sdw_modify_slave_status(struct sdw_slave *slave, __func__, slave->dev_num); init_completion(&slave->enumeration_complete); + init_completion(&slave->initialization_complete); } else if ((status == SDW_SLAVE_ATTACHED) && (slave->status == SDW_SLAVE_UNATTACHED)) { @@ -1025,6 +1026,7 @@ int sdw_handle_slave_status(struct sdw_bus *bus, { enum sdw_slave_status prev_status; struct sdw_slave *slave; + bool attached_initializing; int i, ret = 0; /* first check if any Slaves fell off the bus */ @@ -1070,6 +1072,8 @@ int sdw_handle_slave_status(struct sdw_bus *bus, if (!slave) continue; + attached_initializing = false; + switch (status[i]) { case SDW_SLAVE_UNATTACHED: if (slave->status == SDW_SLAVE_UNATTACHED) @@ -1096,6 +1100,8 @@ int sdw_handle_slave_status(struct sdw_bus *bus, if (prev_status == SDW_SLAVE_ALERT) break; + attached_initializing = true; + ret = sdw_initialize_slave(slave); if (ret) dev_err(bus->dev, @@ -1114,6 +1120,8 @@ int sdw_handle_slave_status(struct sdw_bus *bus, if (ret) dev_err(slave->bus->dev, "Update Slave status failed:%d\n", ret); + if (attached_initializing) + complete(&slave->initialization_complete); } return ret; diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c index e767a78066ee..aace57fae7f8 100644 --- a/drivers/soundwire/slave.c +++ b/drivers/soundwire/slave.c @@ -47,6 +47,7 @@ static int sdw_slave_add(struct sdw_bus *bus, slave->bus = bus; slave->status = SDW_SLAVE_UNATTACHED; init_completion(&slave->enumeration_complete); + init_completion(&slave->initialization_complete); slave->dev_num = 0; init_completion(&slave->probe_complete); slave->probed = false; |