scsi: ufs: Track system suspend / resume activity

Add a new boolean variable that tracks whether the system is suspending,
suspended or resuming. This information will be used in a later commit to
fix a deadlock between the SCSI error handler and the suspend code.
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221018202958.1902564-9-bvanassche@acm.orgSigned-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/ufs/core/ufshcd.c

@@ -9247,6 +9247,7 @@ static int ufshcd_wl_suspend(struct device *dev)
 
 	hba = shost_priv(sdev->host);
 	down(&hba->host_sem);
+	hba->system_suspending = true;
 
 	if (pm_runtime_suspended(dev))
 		goto out;
@@ -9288,6 +9289,7 @@ static int ufshcd_wl_resume(struct device *dev)
 		hba->curr_dev_pwr_mode, hba->uic_link_state);
 	if (!ret)
 		hba->is_sys_suspended = false;
+	hba->system_suspending = false;
 	up(&hba->host_sem);
 	return ret;
 }

include/ufs/ufshcd.h

@@ -802,7 +802,9 @@ struct ufs_hba_monitor {
  * @caps: bitmask with information about UFS controller capabilities
  * @devfreq: frequency scaling information owned by the devfreq core
  * @clk_scaling: frequency scaling information owned by the UFS driver
- * @is_sys_suspended: whether or not the entire system has been suspended
+ * @system_suspending: system suspend has been started and system resume has
+ *	not yet finished.
+ * @is_sys_suspended: UFS device has been suspended because of system suspend
  * @urgent_bkops_lvl: keeps track of urgent bkops level for device
  * @is_urgent_bkops_lvl_checked: keeps track if the urgent bkops level for
  *  device is known or not.
@@ -943,6 +945,7 @@ struct ufs_hba {
 
 	struct devfreq *devfreq;
 	struct ufs_clk_scaling clk_scaling;
+	bool system_suspending;
 	bool is_sys_suspended;
 
 	enum bkops_status urgent_bkops_lvl;