diff mbox series

soundwire: bus: add dev_warn() messages to track UNATTACHED devices

Message ID 20220126011527.27930-1-yung-chuan.liao@linux.intel.com
State New
Headers show
Series soundwire: bus: add dev_warn() messages to track UNATTACHED devices | expand

Commit Message

Liao, Bard Jan. 26, 2022, 1:15 a.m. UTC 
From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>

In rare cases, some devices seem to lose sync and never re-attach on
the bus. This seems to happen only when there are more than one device
per link, which suggests either an electrical issue, a race condition
or a state machine issue.

Add two dev_warn() messages to identify the sequence by which the
devices become UNATTACHED.

BugLink: https://github.com/thesofproject/linux/issues/3063
BugLink: https://github.com/thesofproject/linux/issues/3325
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
---
 drivers/soundwire/bus.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

Vinod Koul Feb. 10, 2022, 1:48 p.m. UTC | #1 
On 26-01-22, 09:15, Bard Liao wrote:
> From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> 
> In rare cases, some devices seem to lose sync and never re-attach on
> the bus. This seems to happen only when there are more than one device
> per link, which suggests either an electrical issue, a race condition
> or a state machine issue.
> 
> Add two dev_warn() messages to identify the sequence by which the
> devices become UNATTACHED.

Applied, thanks
diff mbox series

Patch

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index 67369e941d0d..354d3f89366f 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -1749,8 +1749,11 @@  int sdw_handle_slave_status(struct sdw_bus *bus,
 			continue;
 
 		if (status[i] == SDW_SLAVE_UNATTACHED &&
-		    slave->status != SDW_SLAVE_UNATTACHED)
+		    slave->status != SDW_SLAVE_UNATTACHED) {
+			dev_warn(&slave->dev, "Slave %d state check1: UNATTACHED, status was %d\n",
+				 i, slave->status);
 			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
+		}
 	}
 
 	if (status[0] == SDW_SLAVE_ATTACHED) {
@@ -1785,6 +1788,9 @@  int sdw_handle_slave_status(struct sdw_bus *bus,
 			if (slave->status == SDW_SLAVE_UNATTACHED)
 				break;
 
+			dev_warn(&slave->dev, "Slave %d state check2: UNATTACHED, status was %d\n",
+				 i, slave->status);
+
 			sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
 			break;