From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
Intel stress-tests routinely report IO timeouts and invalid power management transitions. Upon further analysis, we seem to be using the wrong devices in pm_runtime calls.
Before reading and writing registers, we first need to make sure the Slave is fully resumed. The existing code attempts to do such that, however because of a confusion dating from 2017 and copy/paste, we end-up resuming the parent only instead of resuming the codec device.
This can lead to accesses to the Slave registers while the bus is still being configured and the Slave not enumerated, and as a result IO errors occur.
This is a classic problem, similar confusions happened for HDaudio between bus and codec device, leading to power management issues.
Fix by using the relevant device for all uses of pm_runtime functions.
Fixes: 60ee9be255712 ('soundwire: bus: add PM/no-PM versions of read/write functions') Fixes: aa79293517b39 ('soundwire: bus: fix io error when processing alert event') Fixes: 9d715fa005ebc ('soundwire: Add IO transfer') Reported-by: Bard Liao yung-chuan.liao@linux.intel.com Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Rander Wang rander.wang@linux.intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/bus.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 4eaeeb4090f0..7c4717dd9a34 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -513,16 +513,16 @@ int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) { int ret;
- ret = pm_runtime_get_sync(slave->bus->dev); + ret = pm_runtime_get_sync(&slave->dev); if (ret < 0 && ret != -EACCES) { - pm_runtime_put_noidle(slave->bus->dev); + pm_runtime_put_noidle(&slave->dev); return ret; }
ret = sdw_nread_no_pm(slave, addr, count, val);
- pm_runtime_mark_last_busy(slave->bus->dev); - pm_runtime_put(slave->bus->dev); + pm_runtime_mark_last_busy(&slave->dev); + pm_runtime_put(&slave->dev);
return ret; } @@ -539,16 +539,16 @@ int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, u8 *val) { int ret;
- ret = pm_runtime_get_sync(slave->bus->dev); + ret = pm_runtime_get_sync(&slave->dev); if (ret < 0 && ret != -EACCES) { - pm_runtime_put_noidle(slave->bus->dev); + pm_runtime_put_noidle(&slave->dev); return ret; }
ret = sdw_nwrite_no_pm(slave, addr, count, val);
- pm_runtime_mark_last_busy(slave->bus->dev); - pm_runtime_put(slave->bus->dev); + pm_runtime_mark_last_busy(&slave->dev); + pm_runtime_put(&slave->dev);
return ret; } @@ -1453,7 +1453,7 @@ static int sdw_handle_slave_alerts(struct sdw_slave *slave) ret = pm_runtime_get_sync(&slave->dev); if (ret < 0 && ret != -EACCES) { dev_err(&slave->dev, "Failed to resume device: %d\n", ret); - pm_runtime_put_noidle(slave->bus->dev); + pm_runtime_put_noidle(&slave->dev); return ret; }