scsi: ufs: core: Enable power management for wlun

During runtime-suspend of ufs host, the SCSI devices are already suspended
and so are the queues associated with them. However, the ufs host sends SSU
(START_STOP_UNIT) to the wlun during runtime-suspend.

During the process blk_queue_enter() checks if the queue is not in suspended
state. If so, it waits for the queue to resume, and never comes out of
it. Commit 52abca64fd94 ("scsi: block: Do not accept any requests while
suspended") adds the check to see if the queue is in suspended state in
blk_queue_enter().

Call trace:
 __switch_to+0x174/0x2c4
 __schedule+0x478/0x764
 schedule+0x9c/0xe0
 blk_queue_enter+0x158/0x228
 blk_mq_alloc_request+0x40/0xa4
 blk_get_request+0x2c/0x70
 __scsi_execute+0x60/0x1c4
 ufshcd_set_dev_pwr_mode+0x124/0x1e4
 ufshcd_suspend+0x208/0x83c
 ufshcd_runtime_suspend+0x40/0x154
 ufshcd_pltfrm_runtime_suspend+0x14/0x20
 pm_generic_runtime_suspend+0x28/0x3c
 __rpm_callback+0x80/0x2a4
 rpm_suspend+0x308/0x614
 rpm_idle+0x158/0x228
 pm_runtime_work+0x84/0xac
 process_one_work+0x1f0/0x470
 worker_thread+0x26c/0x4c8
 kthread+0x13c/0x320
 ret_from_fork+0x10/0x18

Fix this by registering ufs device wlun as a SCSI driver and registering it
for block runtime-pm. Also make this a supplier for all other LUNs. This
way the wlun device suspends after all the consumers and resumes after HBA
resumes. This also registers a new SCSI driver for rpmb wlun. This new
driver is mostly used to clear rpmb uac.

[mkp: resolve merge conflict with 5.13-rc1 and fix doc warning]

Fixed smatch warnings:
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

Link: https://lore.kernel.org/r/4662c462e79e3e7f541f54f88f8993f421026d83.1619223249.git.asutoshd@codeaurora.org
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Co-developed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/scsi/ufs/ufs-debugfs.c b/drivers/scsi/ufs/ufs-debugfs.c
index ced9ef4d7c78..4e1ff209b933 100644
--- a/drivers/scsi/ufs/ufs-debugfs.c
+++ b/drivers/scsi/ufs/ufs-debugfs.c
@@ -13,7 +13,7 @@ void __init ufs_debugfs_init(void)
 	ufs_debugfs_root = debugfs_create_dir("ufshcd", NULL);
 }
 
-void __exit ufs_debugfs_exit(void)
+void ufs_debugfs_exit(void)
 {
 	debugfs_remove_recursive(ufs_debugfs_root);
 }
@@ -60,14 +60,14 @@ __acquires(&hba->host_sem)
 		up(&hba->host_sem);
 		return -EBUSY;
 	}
-	pm_runtime_get_sync(hba->dev);
+	ufshcd_rpm_get_sync(hba);
 	return 0;
 }
 
 static void ufs_debugfs_put_user_access(struct ufs_hba *hba)
 __releases(&hba->host_sem)
 {
-	pm_runtime_put_sync(hba->dev);
+	ufshcd_rpm_put_sync(hba);
 	up(&hba->host_sem);
 }