Commit d1b32855 authored Jan 26, 2022 by Pierre-Louis Bossart Committed by Vinod Koul Feb 10, 2022

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

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>
Link: https://lore.kernel.org/r/20220126011527.27930-1-yung-chuan.liao@linux.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>

parent e783362e

drivers/soundwire/bus.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -1749,9 +1749,12 @@ 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) {
		dev_dbg(bus->dev, "Slave attached, programming device number\n");
		@@ -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;