Applied to 6.2/scsi-staging, thanks!
There is an interesting side effect of the patch in this iteration (which I am not sure was present in the past iteration I tried): If the device auto suspends while running purge - controller is seemingly recent and thus the purge is aborted (with no patch at all it hangs). That might be ok behaviour though - it will just make it an explicit requirement to disable runtime suspend during the management operation.
localhost ~ # ufs-utils fl -t 6 -e -p /dev/bsg/ufs-bsg0 localhost ~ # ufs-utils attr -a -p /dev/bsg/ufs-bsg0 | grep bPurgeStatus bPurgeStatus := 0x00
[ 25.801980] ufs_device_wlun 0:0:0:49488: START_STOP failed for power mode: 2, result 2 [ 25.802002] ufs_device_wlun 0:0:0:49488: Sense Key : Not Ready [current] [ 25.802009] ufs_device_wlun 0:0:0:49488: Add. Sense: No additional sense information [ 25.802020] ufs_device_wlun 0:0:0:49488: ufshcd_wl_runtime_suspend failed: -16