Enable power management for ufs wlun

During runtime-suspend of ufs host, the scsi devices are already suspended and so are the queues associated with them. But the ufs host sends SSU to wlun during its 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.
The commit
(d55d15a33: scsi: block: Do not accept any requests while suspended) adds the check 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 as a supplier for all other luns. That way, this device wlun suspends after all the consumers and resumes after hba resumes.

Co-developed-by Can Guo <[email protected]>

Signed-off-by Can Guo <[email protected]>

Signed-off-by Asutosh Das <[email protected]>

---
 drivers/scsi/ufs/ufs-qcom.c      |   2 +
 drivers/scsi/ufs/ufshcd-pci.c    |  24 --
 drivers/scsi/ufs/ufshcd-pltfrm.c |  29 +++
 drivers/scsi/ufs/ufshcd-pltfrm.h |   4 +
 drivers/scsi/ufs/ufshcd.c        | 491 +++++++++++++++++++++++++++++++--------
 drivers/scsi/ufs/ufshcd.h        |   5 +
 include/trace/events/ufs.h       |  20 ++
 7 files changed, 454 insertions(+), 121 deletions(-)

drivers/scsi/ufs/ufs-qcom.c +0 -0

index f97d7b0..8cd8cfd 100644

drivers/scsi/ufs/ufs-qcom.c +0 -0

 };
 
 static struct platform_driver ufs_qcom_pltform = {

drivers/scsi/ufs/ufshcd-pci.c +0 -24

index fadd566..ab84d56 100644
@@ -247,29 +247,6 @@ static int ufshcd_pci_resume(struct device *dev)
 	return ufshcd_system_resume(dev_get_drvdata(dev));
 }
 
-/**
- * ufshcd_pci_poweroff - suspend-to-disk poweroff function
- * @dev: pointer to PCI device handle
- *
- * Returns 0 if successful
- * Returns non-zero otherwise
- */
-static int ufshcd_pci_poweroff(struct device *dev)
-{
-	struct ufs_hba *hba = dev_get_drvdata(dev);
-	int spm_lvl = hba->spm_lvl;
-	int ret;
-
-	/*
-	 * For poweroff we need to set the UFS device to PowerDown mode.
-	 * Force spm_lvl to ensure that.
-	 */
-	hba->spm_lvl = 5;
-	ret = ufshcd_system_suspend(hba);
-	hba->spm_lvl = spm_lvl;
-	return ret;
-}
-
 #endif /* !CONFIG_PM_SLEEP */
 
 #ifdef CONFIG_PM

@@ -370,7 +347,6 @@ static const struct dev_pm_ops ufshcd_pci_pm_ops = {
 	.resume		= ufshcd_pci_resume,
 	.freeze		= ufshcd_pci_suspend,
 	.thaw		= ufshcd_pci_resume,
-	.poweroff	= ufshcd_pci_poweroff,
 	.restore	= ufshcd_pci_resume,
 #endif
 	SET_RUNTIME_PM_OPS(ufshcd_pci_runtime_suspend,

drivers/scsi/ufs/ufshcd-pltfrm.c +0 -0

index 1a69949..84550dc 100644
@@ -217,6 +217,35 @@ int ufshcd_pltfrm_runtime_idle(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(ufshcd_pltfrm_runtime_idle);
 

drivers/scsi/ufs/ufshcd-pltfrm.c +0 -0

 #endif /* CONFIG_PM */
 
 void ufshcd_pltfrm_shutdown(struct platform_device *pdev)

drivers/scsi/ufs/ufshcd-pltfrm.h +4 -0

index 772a8e8..caf2709 100644
@@ -40,6 +40,8 @@ int ufshcd_pltfrm_resume(struct device *dev);
 int ufshcd_pltfrm_runtime_suspend(struct device *dev);
 int ufshcd_pltfrm_runtime_resume(struct device *dev);
 int ufshcd_pltfrm_runtime_idle(struct device *dev);
+int ufshcd_pltfrm_prepare(struct device *dev);
+int ufshcd_pltfrm_resume_early(struct device *dev);
 
 #else /* !CONFIG_PM */
 

@@ -48,6 +50,8 @@ int ufshcd_pltfrm_runtime_idle(struct device *dev);
 #define ufshcd_pltfrm_runtime_suspend	NULL
 #define ufshcd_pltfrm_runtime_resume	NULL
 #define ufshcd_pltfrm_runtime_idle	NULL
+#define ufshcd_pltfrm_prepare	NULL
+#define ufshcd_pltfrm_resume_early	NULL
 
 #endif /* CONFIG_PM */
 

drivers/scsi/ufs/ufshcd.c +79 -23

index 45624c7..bc96544 100644
@@ -16,6 +16,7 @@
 #include <linux/bitfield.h>
 #include <linux/blk-pm.h>
 #include <linux/blkdev.h>
+#include <scsi/scsi_driver.h>
 #include "ufshcd.h"
 #include "ufs_quirks.h"
 #include "unipro.h"

@@ -78,6 +79,8 @@
 /* Polling time to wait for fDeviceInit */
 #define FDEVICEINIT_COMPL_TIMEOUT 1500 /* millisecs */
 
+#define wlun_dev_to_hba(dv) shost_priv(to_scsi_device(dv)->host)
+
 #define ufshcd_toggle_vreg(_dev, _vreg, _on)				\
 	({                                                              \
 		int _ret;                                               \

@@ -251,6 +254,12 @@ static int ufshcd_wb_toggle_flush_during_h8(struct ufs_hba *hba, bool set);
 static inline int ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool enable);
 static void ufshcd_hba_vreg_set_lpm(struct ufs_hba *hba);
 static void ufshcd_hba_vreg_set_hpm(struct ufs_hba *hba);
+static int ufshcd_wl_runtime_suspend(struct device *dev);
+static int ufshcd_wl_runtime_resume(struct device *dev);
+static int ufshcd_wl_suspend(struct device *dev);
+static int ufshcd_wl_resume(struct device *dev);
+static void ufshcd_wl_shutdown(struct device *dev);
+static int ufshcd_clear_ua_wlun(struct ufs_hba *hba, u8 wlun);
 
 static inline bool ufshcd_valid_tag(struct ufs_hba *hba, int tag)
 {

@@ -1556,7 +1565,7 @@ static ssize_t ufshcd_clkscale_enable_store(struct device *dev,
 	if (value == hba->clk_scaling.is_enabled)
 		goto out;
 
-	pm_runtime_get_sync(hba->dev);
+	scsi_autopm_get_device(hba->sdev_ufs_device);
 	ufshcd_hold(hba, false);
 
 	hba->clk_scaling.is_enabled = value;

@@ -1572,7 +1581,7 @@ static ssize_t ufshcd_clkscale_enable_store(struct device *dev,
 	}
 
 	ufshcd_release(hba);
-	pm_runtime_put_sync(hba->dev);
+	scsi_autopm_put_device(hba->sdev_ufs_device);
 out:
 	up(&hba->host_sem);
 	return err ? err : count;

@@ -2572,6 +2581,17 @@ static inline u16 ufshcd_upiu_wlun_to_scsi_wlun(u8 upiu_wlun_id)
 	return (upiu_wlun_id & ~UFS_UPIU_WLUN_ID) | SCSI_W_LUN_BASE;
 }
 
+static inline bool is_rpmb_wlun(struct scsi_device *sdev)
+{
+	return (sdev->lun == ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_RPMB_WLUN));
+}
+
+static inline bool is_device_wlun(struct scsi_device *sdev)
+{
+	return (sdev->lun ==
+		ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_UFS_DEVICE_WLUN));
+}
+
 static void ufshcd_init_lrb(struct ufs_hba *hba, struct ufshcd_lrb *lrb, int i)
 {
 	struct utp_transfer_cmd_desc *cmd_descp = hba->ucdl_base_addr;

@@ -4808,6 +4828,41 @@ static inline void ufshcd_get_lu_power_on_wp_status(struct ufs_hba *hba,
 }
 
 /**
+ * ufshcd_setup_links - associate link b/w device wlun and other luns
+ * @sdev: pointer to SCSI device
+ * @hba: pointer to ufs hba
+ */
+static void ufshcd_setup_links(struct ufs_hba *hba, struct scsi_device *sdev)
+{
+	struct device_link *link;
+
+	/*
+	 * device wlun is the supplier & rest of the luns are consumers
+	 * This ensures that device wlun suspends after all other luns.
+	 */
+	if (hba->sdev_ufs_device) {
+		link = device_link_add(&sdev->sdev_gendev,
+				       &hba->sdev_ufs_device->sdev_gendev,
+				       DL_FLAG_PM_RUNTIME);
+		if (!link) {
+			dev_err(&sdev->sdev_gendev, "Failed establishing link - %s\n",
+				dev_name(&hba->sdev_ufs_device->sdev_gendev));
+			return;
+		}
+		hba->luns_avail--;
+		/* Ignore REPORT_LUN wlun probing */
+		if (hba->luns_avail != 1)
+			return;
+
+		pm_runtime_put_noidle(&hba->sdev_ufs_device->sdev_gendev);
+		pm_runtime_mark_last_busy(&hba->sdev_ufs_device->sdev_gendev);
+	} else {
+		/* device wlun is probed */
+		hba->luns_avail--;
+	}
+}
+
+/**
  * ufshcd_slave_alloc - handle initial SCSI device configurations
  * @sdev: pointer to SCSI device
  *

@@ -4838,6 +4893,8 @@ static int ufshcd_slave_alloc(struct scsi_device *sdev)
 
 	ufshcd_get_lu_power_on_wp_status(hba, sdev);
 
+	ufshcd_setup_links(hba, sdev);
+
 	return 0;
 }
 

@@ -4984,16 +5041,9 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 			 * solution could be to abort the system suspend if
 			 * UFS device needs urgent BKOPs.
 			 */
-			if (!hba->pm_op_in_progress &&
-			    ufshcd_is_exception_event(lrbp->ucd_rsp_ptr) &&
-			    schedule_work(&hba->eeh_work)) {
-				/*
-				 * Prevent suspend once eeh_work is scheduled
-				 * to avoid deadlock between ufshcd_suspend
-				 * and exception event handler.
-				 */
-				pm_runtime_get_noresume(hba->dev);
-			}
+			if (ufshcd_is_exception_event(lrbp->ucd_rsp_ptr))
+				/* Flushed in suspend */
+				schedule_work(&hba->eeh_work);
 			break;
 		case UPIU_TRANSACTION_REJECT_UPIU:
 			/* TODO: handle Reject UPIU Response */

@@ -5589,8 +5639,8 @@ static void ufshcd_rpm_dev_flush_recheck_work(struct work_struct *work)
 	 * after a certain delay to recheck the threshold by next runtime
 	 * suspend.
 	 */
-	pm_runtime_get_sync(hba->dev);
-	pm_runtime_put_sync(hba->dev);
+	scsi_autopm_get_device(hba->sdev_ufs_device);
+	scsi_autopm_put_device(hba->sdev_ufs_device);
 }
 
 /**

@@ -5607,7 +5657,6 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
 	u32 status = 0;
 	hba = container_of(work, struct ufs_hba, eeh_work);
 
-	pm_runtime_get_sync(hba->dev);
 	ufshcd_scsi_block_requests(hba);
 	err = ufshcd_get_ee_status(hba, &status);
 	if (err) {

@@ -5623,14 +5672,6 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
 
 out:
 	ufshcd_scsi_unblock_requests(hba);
-	/*
-	 * pm_runtime_get_noresume is called while scheduling
-	 * eeh_work to avoid suspend racing with exception work.
-	 * Hence decrement usage counter using pm_runtime_put_noidle
-	 * to allow suspend on completion of exception event handler.
-	 */
-	pm_runtime_put_noidle(hba->dev);
-	pm_runtime_put(hba->dev);
 	return;
 }
 

@@ -7254,6 +7295,15 @@ static int ufshcd_scsi_add_wlus(struct ufs_hba *hba)
 		goto out;
 	}
 	ufshcd_blk_pm_runtime_init(hba->sdev_ufs_device);
+	/*
+	 * A pm_runtime_put_sync is invoked when this device enables blk_pm_runtime
+	 * & would suspend the device-wlun upon timer expiry.
+	 * But suspending device wlun _may_ put the ufs device in the pre-defined
+	 * low power mode (SSU <rpm_lvl>). Probing of other luns may fail then.
+	 * Don't allow this suspend until all the luns have been probed.
+	 * See pm_runtime_mark_last_busy in ufshcd_setup_links.
+	 */
+	pm_runtime_get_noresume(&hba->sdev_ufs_device->sdev_gendev);
 	scsi_device_put(hba->sdev_ufs_device);
 
 	hba->sdev_rpmb = __scsi_add_device(hba->host, 0, 0,

@@ -7417,6 +7467,9 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
 		goto out;
 	}
 
+	hba->luns_avail = desc_buf[DEVICE_DESC_PARAM_NUM_LU] +
+		desc_buf[DEVICE_DESC_PARAM_NUM_WLU];
+
 	ufs_fixup_device_setup(hba);
 
 	ufshcd_wb_probe(hba, desc_buf);

@@ -7747,6 +7800,95 @@ static int ufshcd_device_params_init(struct ufs_hba *hba)
 	return ret;
 }
 
+static int ufshcd_wl_probe(struct device *dev)
+{
+	return is_device_wlun(to_scsi_device(dev)) ? 0 : -ENODEV;

drivers/scsi/ufs/ufshcd.c +76 -0

+};
+
+/**
+ * ufs_dev_wlun_template - describes ufs device wlun
+ * ufs-device wlun - used to send pm commands
+ * All luns are consumers of ufs-device wlun.
+ *
+ * Currently, no sd driver is present for wluns.
+ * Hence the no specific pm operations are performed.
+ * With ufs design, SSU should be sent to ufs-device wlun.
+ * Hence register a scsi driver for ufs wluns only.
+ */
+static struct scsi_driver ufs_dev_wlun_template = {
+	.gendrv = {
+		.name = "ufs_device_wlun",
+		.owner = THIS_MODULE,
+		.probe = ufshcd_wl_probe,
+		.remove = ufshcd_wl_remove,
+		.pm = &ufshcd_wl_pm_ops,
+		.shutdown = ufshcd_wl_shutdown,
+	},
+};
+
+static int ufshcd_rpmb_probe(struct device *dev)
+{
+	return is_rpmb_wlun(to_scsi_device(dev)) ? 0 : -ENODEV;
+}
+
+static inline int ufshcd_clear_rpmb_uac(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+	if (!hba->wlun_rpmb_clr_ua)
+		return 0;
+	ret = ufshcd_clear_ua_wlun(hba, UFS_UPIU_RPMB_WLUN);
+	if (!ret)
+		hba->wlun_rpmb_clr_ua = 0;
+	return ret;
+}
+
+static int ufshcd_rpmb_runtime_resume(struct device *dev)
+{
+	struct ufs_hba *hba = wlun_dev_to_hba(dev);
+
+	if (hba->sdev_rpmb)
+		return ufshcd_clear_rpmb_uac(hba);
+	return 0;
+}
+
+static int ufshcd_rpmb_resume(struct device *dev)
+{
+	struct ufs_hba *hba = wlun_dev_to_hba(dev);
+
+	if (hba->sdev_rpmb && !pm_runtime_suspended(dev))
+		return ufshcd_clear_rpmb_uac(hba);
+	return 0;
+}
+
+static const struct dev_pm_ops ufs_rpmb_pm_ops = {
+	SET_RUNTIME_PM_OPS(NULL, ufshcd_rpmb_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(NULL, ufshcd_rpmb_resume)
+};
+
+/**
+ * Describes the ufs rpmb wlun.
+ * Used only to send uac.
+ */
+static struct scsi_driver ufs_rpmb_wlun_template = {
+	.gendrv = {
+		.name = "ufs_rpmb_wlun",
+		.owner = THIS_MODULE,
+		.probe = ufshcd_rpmb_probe,
+		.pm = &ufs_rpmb_pm_ops,
+	},
+};
+
 /**
  * ufshcd_add_lus - probe and add UFS logical units
  * @hba: per-adapter instance

drivers/scsi/ufs/ufshcd.c +223 -74

+
+	ret = scsi_register_driver(&ufs_rpmb_wlun_template.gendrv);
+	if (ret) {
+		dev_err(hba->dev, "Register device wlun driver failed: %d\n",
+			ret);
+		return ret;
+	}
 	/* Add required well known logical units to scsi mid layer */
 	ret = ufshcd_scsi_add_wlus(hba);
 	if (ret)

@@ -7892,6 +8047,7 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool async)
 	ufshcd_set_ufs_dev_active(hba);
 	ufshcd_force_reset_auto_bkops(hba);
 	hba->wlun_dev_clr_ua = true;
+	hba->wlun_rpmb_clr_ua = true;
 
 	/* Gear up to HS gear if supported */
 	if (hba->max_pwr_info.is_valid) {

@@ -7964,6 +8120,7 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 		pm_runtime_put_sync(hba->dev);
 		ufshcd_hba_exit(hba);
 	}
+	hba->init_done = true;
 }
 
 static const struct attribute_group *ufshcd_driver_groups[] = {

@@ -8475,7 +8632,8 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
 	 * handling context.
 	 */
 	hba->host->eh_noresume = 1;
-	ufshcd_clear_ua_wluns(hba);
+	if (hba->wlun_dev_clr_ua)
+		ufshcd_clear_ua_wlun(hba, UFS_UPIU_UFS_DEVICE_WLUN);
 
 	cmd[4] = pwr_mode << 4;
 

@@ -8650,31 +8808,19 @@ static void ufshcd_hba_vreg_set_hpm(struct ufs_hba *hba)
 		ufshcd_setup_hba_vreg(hba, true);
 }
 
-/**
- * ufshcd_suspend - helper function for suspend operations
- * @hba: per adapter instance
- * @pm_op: desired low power operation type
- *
- * This function will try to put the UFS device and link into low power
- * mode based on the "rpm_lvl" (Runtime PM level) or "spm_lvl"
- * (System PM level).
- *
- * If this function is called during shutdown, it will make sure that
- * both UFS device and UFS link is powered off.
- *
- * NOTE: UFS device & link must be active before we enter in this function.
- *
- * Returns 0 for success and non-zero for failure
- */
-static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+static int __ufshcd_wl_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 {
 	int ret = 0;
-	int check_for_bkops;
 	enum ufs_pm_level pm_lvl;
 	enum ufs_dev_pwr_mode req_dev_pwr_mode;
 	enum uic_link_state req_link_state;
 
-	hba->pm_op_in_progress = 1;
+	/*
+	 * Is invoked when the device wlun is added to sysfs
+	 * But by then hba->sdev_ufs_device may not be initialized.
+	 */
+	if (!hba->init_done)
+		return 0;
 	if (!ufshcd_is_shutdown_pm(pm_op)) {
 		pm_lvl = ufshcd_is_runtime_pm(pm_op) ?
 			 hba->rpm_lvl : hba->spm_lvl;

@@ -8690,24 +8836,23 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	 * just gate the clocks.
 	 */
 	ufshcd_hold(hba, false);
-	hba->clk_gating.is_suspended = true;
 
 	if (ufshcd_is_clkscaling_supported(hba))
 		ufshcd_clk_scaling_suspend(hba, true);
 
 	if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE &&
 			req_link_state == UIC_LINK_ACTIVE_STATE) {
-		goto disable_clks;
+		goto enable_scaling;
 	}
 
 	if ((req_dev_pwr_mode == hba->curr_dev_pwr_mode) &&
 	    (req_link_state == hba->uic_link_state))
-		goto enable_gating;
+		goto enable_scaling;
 
 	/* UFS device & link must be active before we enter in this function */
 	if (!ufshcd_is_ufs_dev_active(hba) || !ufshcd_is_link_active(hba)) {
 		ret = -EINVAL;
-		goto enable_gating;
+		goto enable_scaling;
 	}
 
 	if (ufshcd_is_runtime_pm(pm_op)) {

@@ -8719,7 +8864,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 			 */
 			ret = ufshcd_urgent_bkops(hba);
 			if (ret)
-				goto enable_gating;
+				goto enable_scaling;
 		} else {
 			/* make sure that auto bkops is disabled */
 			ufshcd_disable_auto_bkops(hba);

@@ -8746,10 +8891,206 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 
 		if (!hba->dev_info.b_rpm_dev_flush_capable) {
 			ret = ufshcd_set_dev_pwr_mode(hba, req_dev_pwr_mode);
-			if (ret)
-				goto enable_gating;
+			if (!ret)
+				goto out;
 		}
 	}
+enable_scaling:
+	if (ufshcd_is_clkscaling_supported(hba))
+		ufshcd_clk_scaling_suspend(hba, false);
+
+	hba->dev_info.b_rpm_dev_flush_capable = false;
+out:
+	if (hba->dev_info.b_rpm_dev_flush_capable) {
+		schedule_delayed_work(&hba->rpm_dev_flush_recheck_work,
+			msecs_to_jiffies(RPM_DEV_FLUSH_RECHECK_WORK_DELAY_MS));
+	}
+	if (ret)
+		ufshcd_update_evt_hist(hba, UFS_EVT_WL_SUSP_ERR, (u32)ret);
+	ufshcd_release(hba);
+	return ret;
+}
+
+static int __ufshcd_wl_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+{
+	int ret = 0;
+
+	if (!hba->init_done)
+		return 0;
+
+	ufshcd_hold(hba, false);
+	if (ufshcd_is_ufs_dev_deepsleep(hba)) {
+		/* The device is in DeepSleep but hba was not suspended */
+		ret = ufshcd_reset_and_restore(hba);
+		if (ret)
+			goto out;
+	}
+
+	if (!ufshcd_is_ufs_dev_active(hba)) {
+		ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE);
+		if (ret)
+			goto out;
+	}
+
+	if (ufshcd_keep_autobkops_enabled_except_suspend(hba))
+		ufshcd_enable_auto_bkops(hba);
+	else
+		/*
+		 * If BKOPs operations are urgently needed at this moment then
+		 * keep auto-bkops enabled or else disable it.
+		 */
+		ufshcd_urgent_bkops(hba);
+
+	if (hba->clk_scaling.is_allowed)
+		ufshcd_resume_clkscaling(hba);
+
+	if (hba->dev_info.b_rpm_dev_flush_capable) {
+		hba->dev_info.b_rpm_dev_flush_capable = false;
+		cancel_delayed_work(&hba->rpm_dev_flush_recheck_work);
+	}
+
+out:
+	if (ret)
+		ufshcd_update_evt_hist(hba, UFS_EVT_WL_RES_ERR, (u32)ret);
+	ufshcd_release(hba);
+	return ret;
+}
+
+static int ufshcd_wl_runtime_suspend(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+	int ret;
+	ktime_t start = ktime_get();
+
+	hba = shost_priv(sdev->host);
+
+	ret = __ufshcd_wl_suspend(hba, UFS_RUNTIME_PM);
+	if (ret)
+		dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__, ret);
+
+	trace_ufshcd_wl_runtime_suspend(dev_name(dev), ret,
+		ktime_to_us(ktime_sub(ktime_get(), start)),
+		hba->curr_dev_pwr_mode, hba->uic_link_state);
+
+	return ret;
+}
+
+static int ufshcd_wl_runtime_resume(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+	int ret = 0;
+	ktime_t start = ktime_get();
+
+	hba = shost_priv(sdev->host);
+
+	ret = __ufshcd_wl_resume(hba, UFS_RUNTIME_PM);
+	if (ret)
+		dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__, ret);
+
+	trace_ufshcd_wl_runtime_resume(dev_name(dev), ret,
+		ktime_to_us(ktime_sub(ktime_get(), start)),
+		hba->curr_dev_pwr_mode, hba->uic_link_state);
+
+	return ret;
+}
+
+static int ufshcd_wl_suspend(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+	int ret;
+	ktime_t start = ktime_get();
+
+	hba = shost_priv(sdev->host);
+	ret = __ufshcd_wl_suspend(hba, UFS_SYSTEM_PM);
+	if (ret)
+		dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__,  ret);
+
+	trace_ufshcd_wl_suspend(dev_name(dev), ret,
+		ktime_to_us(ktime_sub(ktime_get(), start)),
+		hba->curr_dev_pwr_mode, hba->uic_link_state);
+
+	return ret;
+}
+
+static int ufshcd_wl_resume(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+	int ret = 0;
+	ktime_t start = ktime_get();
+
+	if (pm_runtime_suspended(dev))
+		return 0;
+	hba = shost_priv(sdev->host);
+
+	ret = __ufshcd_wl_resume(hba, UFS_SYSTEM_PM);
+	if (ret)
+		dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__, ret);
+
+	trace_ufshcd_wl_resume(dev_name(dev), ret,
+		ktime_to_us(ktime_sub(ktime_get(), start)),
+		hba->curr_dev_pwr_mode, hba->uic_link_state);
+
+	return ret;
+}
+
+static void ufshcd_wl_shutdown(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+
+	hba = shost_priv(sdev->host);
+	scsi_device_quiesce(sdev);
+	shost_for_each_device(sdev, hba->host) {
+		if (sdev == hba->sdev_ufs_device)
+			continue;
+		scsi_device_quiesce(sdev);
+	}
+	__ufshcd_wl_suspend(hba, UFS_SHUTDOWN_PM);
+}
+
+/**
+ * ufshcd_suspend - helper function for suspend operations
+ * @hba: per adapter instance
+ * @pm_op: desired low power operation type
+ *
+ * This function will try to put the UFS link into low power
+ * mode based on the "rpm_lvl" (Runtime PM level) or "spm_lvl"
+ * (System PM level).
+ *
+ * If this function is called during shutdown, it will make sure that
+ * link is powered off.
+ *
+ * Returns 0 for success and non-zero for failure
+ */
+static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+{
+	int ret = 0;
+	int check_for_bkops;
+	enum ufs_pm_level pm_lvl;
+	enum ufs_dev_pwr_mode req_dev_pwr_mode;
+	enum uic_link_state req_link_state;
+
+	hba->pm_op_in_progress = 1;
+	if (!ufshcd_is_shutdown_pm(pm_op)) {
+		pm_lvl = ufshcd_is_runtime_pm(pm_op) ?
+			 hba->rpm_lvl : hba->spm_lvl;
+		req_dev_pwr_mode = ufs_get_pm_lvl_to_dev_pwr_mode(pm_lvl);
+		req_link_state = ufs_get_pm_lvl_to_link_pwr_state(pm_lvl);
+	} else {
+		req_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE;
+		req_link_state = UIC_LINK_OFF_STATE;
+	}
+
+	/*
+	 * If we can't transition into any of the low power modes
+	 * just gate the clocks.
+	 */
+	ufshcd_hold(hba, false);
+	hba->clk_gating.is_suspended = true;
 
 	/*
 	 * In the case of DeepSleep, the device is expected to remain powered

@@ -8758,9 +9099,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	check_for_bkops = !ufshcd_is_ufs_dev_deepsleep(hba);
 	ret = ufshcd_link_state_transition(hba, req_link_state, check_for_bkops);
 	if (ret)
-		goto set_dev_active;
+		goto enable_gating;
 
-disable_clks:
 	/*
 	 * Call vendor specific suspend callback. As these callbacks may access
 	 * vendor specific host controller register space call them before the

@@ -8790,7 +9130,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	goto out;
 
 set_link_active:
-	ufshcd_vreg_set_hpm(hba);
 	/*
 	 * Device hardware reset is required to exit DeepSleep. Also, for
 	 * DeepSleep, the link is off so host reset and restore will be done

@@ -8804,28 +9143,15 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 		ufshcd_set_link_active(hba);
 	else if (ufshcd_is_link_off(hba))
 		ufshcd_host_reset_and_restore(hba);
-set_dev_active:
 	/* Can also get here needing to exit DeepSleep */
 	if (ufshcd_is_ufs_dev_deepsleep(hba)) {
 		ufshcd_device_reset(hba);
 		ufshcd_host_reset_and_restore(hba);
 	}
-	if (!ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE))
-		ufshcd_disable_auto_bkops(hba);
 enable_gating:
-	if (ufshcd_is_clkscaling_supported(hba))
-		ufshcd_clk_scaling_suspend(hba, false);
-
 	hba->clk_gating.is_suspended = false;
-	hba->dev_info.b_rpm_dev_flush_capable = false;
-	ufshcd_clear_ua_wluns(hba);
 	ufshcd_release(hba);
 out:
-	if (hba->dev_info.b_rpm_dev_flush_capable) {
-		schedule_delayed_work(&hba->rpm_dev_flush_recheck_work,
-			msecs_to_jiffies(RPM_DEV_FLUSH_RECHECK_WORK_DELAY_MS));
-	}
-
 	hba->pm_op_in_progress = 0;
 
 	if (ret)

@@ -8846,10 +9172,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 {
 	int ret;
-	enum uic_link_state old_link_state;
 
 	hba->pm_op_in_progress = 1;
-	old_link_state = hba->uic_link_state;
 
 	ufshcd_hba_vreg_set_hpm(hba);
 	ret = ufshcd_vreg_set_hpm(hba);

@@ -8901,43 +9225,14 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 			goto vendor_suspend;
 	}
 
-	if (!ufshcd_is_ufs_dev_active(hba)) {
-		ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE);
-		if (ret)
-			goto set_old_link_state;
-	}
-
-	if (ufshcd_keep_autobkops_enabled_except_suspend(hba))
-		ufshcd_enable_auto_bkops(hba);
-	else
-		/*
-		 * If BKOPs operations are urgently needed at this moment then
-		 * keep auto-bkops enabled or else disable it.
-		 */
-		ufshcd_urgent_bkops(hba);
-
-	hba->clk_gating.is_suspended = false;
-
-	if (ufshcd_is_clkscaling_supported(hba))
-		ufshcd_clk_scaling_suspend(hba, false);
-
 	/* Enable Auto-Hibernate if configured */
 	ufshcd_auto_hibern8_enable(hba);
 
-	if (hba->dev_info.b_rpm_dev_flush_capable) {
-		hba->dev_info.b_rpm_dev_flush_capable = false;
-		cancel_delayed_work(&hba->rpm_dev_flush_recheck_work);
-	}
-
-	ufshcd_clear_ua_wluns(hba);
-
 	/* Schedule clock gating in case of no access to UFS device yet */
 	ufshcd_release(hba);
 
 	goto out;
 
-set_old_link_state:
-	ufshcd_link_state_transition(hba, old_link_state, 0);
 vendor_suspend:
 	ufshcd_vops_suspend(hba, pm_op);
 disable_irq_and_vops_clks:

@@ -9170,6 +9465,8 @@ EXPORT_SYMBOL(ufshcd_shutdown);
 void ufshcd_remove(struct ufs_hba *hba)
 {
 	ufs_bsg_remove(hba);
+	scsi_unregister_driver(&ufs_dev_wlun_template.gendrv);
+	scsi_unregister_driver(&ufs_rpmb_wlun_template.gendrv);
 	ufs_sysfs_remove_nodes(hba->dev);
 	blk_cleanup_queue(hba->tmf_queue);
 	blk_mq_free_tag_set(&hba->tmf_tag_set);

drivers/scsi/ufs/ufshcd.h +5 -0

index ee61f82..9087593 100644
@@ -72,6 +72,8 @@ enum ufs_event_type {
 	UFS_EVT_LINK_STARTUP_FAIL,
 	UFS_EVT_RESUME_ERR,
 	UFS_EVT_SUSPEND_ERR,
+	UFS_EVT_WL_SUSP_ERR,
+	UFS_EVT_WL_RES_ERR,
 
 	/* abnormal events */
 	UFS_EVT_DEV_RESET,

@@ -804,6 +806,7 @@ struct ufs_hba {
 	struct list_head clk_list_head;
 
 	bool wlun_dev_clr_ua;
+	bool wlun_rpmb_clr_ua;
 
 	/* Number of requests aborts */
 	int req_abort_count;

@@ -841,6 +844,8 @@ struct ufs_hba {
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *debugfs_root;
 #endif
+	bool init_done;
+	u32 luns_avail;
 };
 
 /* Returns true if clocks can be gated. Otherwise false */

include/trace/events/ufs.h +20 -0

index e151477..d9d233b 100644
@@ -246,6 +246,26 @@ DEFINE_EVENT(ufshcd_template, ufshcd_init,
 		      int dev_state, int link_state),
 	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
 
+DEFINE_EVENT(ufshcd_template, ufshcd_wl_suspend,
+	     TP_PROTO(const char *dev_name, int err, s64 usecs,
+		      int dev_state, int link_state),
+	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
+
+DEFINE_EVENT(ufshcd_template, ufshcd_wl_resume,
+	     TP_PROTO(const char *dev_name, int err, s64 usecs,
+		      int dev_state, int link_state),
+	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
+
+DEFINE_EVENT(ufshcd_template, ufshcd_wl_runtime_suspend,
+	     TP_PROTO(const char *dev_name, int err, s64 usecs,
+		      int dev_state, int link_state),
+	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
+
+DEFINE_EVENT(ufshcd_template, ufshcd_wl_runtime_resume,
+	     TP_PROTO(const char *dev_name, int err, s64 usecs,
+		      int dev_state, int link_state),
+	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
+
 TRACE_EVENT(ufshcd_command,
 	TP_PROTO(const char *dev_name, enum ufs_trace_str_t str_t,
 		 unsigned int tag, u32 doorbell, int transfer_len, u32 intr,

Quoted 51 lines · Asutosh Das

During runtime-suspend of ufs host, the scsi devices are already suspended and so are the queues associated with them. But the ufs host sends SSU to wlun during its 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.
The commit
(d55d15a33: scsi: block: Do not accept any requests while suspended) adds the check 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 as a supplier for all other luns. That way, this device wlun suspends after all the consumers and resumes after hba resumes.

Co-developed-by Can Guo <[email protected]>

Signed-off-by Can Guo <[email protected]>

Signed-off-by Asutosh Das <[email protected]>

---
 drivers/scsi/ufs/ufs-qcom.c      |   2 +
 drivers/scsi/ufs/ufshcd-pci.c    |  24 --
 drivers/scsi/ufs/ufshcd-pltfrm.c |  29 +++
 drivers/scsi/ufs/ufshcd-pltfrm.h |   4 +
 drivers/scsi/ufs/ufshcd.c        | 491 +++++++++++++++++++++++++++++++--------
 drivers/scsi/ufs/ufshcd.h        |   5 +
 include/trace/events/ufs.h       |  20 ++
 7 files changed, 454 insertions(+), 121 deletions(-)

drivers/scsi/ufs/ufs-qcom.c static const struct dev_pm_ops ufs_qcom_pm_ops = { · line 1550

Quoted 10 lines

drivers/scsi/ufs/ufs-qcom.c +2 -0

index f97d7b0..8cd8cfd 100644
@@ -1546,6 +1546,8 @@ static const struct dev_pm_ops ufs_qcom_pm_ops = {
 	.runtime_suspend = ufshcd_pltfrm_runtime_suspend,
 	.runtime_resume  = ufshcd_pltfrm_runtime_resume,
 	.runtime_idle    = ufshcd_pltfrm_runtime_idle,
+	.prepare	= ufshcd_pltfrm_prepare,
+	.resume_early	= ufshcd_pltfrm_resume_early,

The pair for the "prepare" callback is the "complete" callback rather than "resume_early"

Presumably all drivers will need this kind of change.

Quoted 1 line

drivers/scsi/ufs/ufs-qcom.c +0 -0

 };

Quoted 52 lines

drivers/scsi/ufs/ufs-qcom.c +0 -0

 static struct platform_driver ufs_qcom_pltform = {

drivers/scsi/ufs/ufshcd-pci.c +0 -24

index fadd566..ab84d56 100644
@@ -247,29 +247,6 @@ static int ufshcd_pci_resume(struct device *dev)
 	return ufshcd_system_resume(dev_get_drvdata(dev));
 }
 
-/**
- * ufshcd_pci_poweroff - suspend-to-disk poweroff function
- * @dev: pointer to PCI device handle
- *
- * Returns 0 if successful
- * Returns non-zero otherwise
- */
-static int ufshcd_pci_poweroff(struct device *dev)
-{
-	struct ufs_hba *hba = dev_get_drvdata(dev);
-	int spm_lvl = hba->spm_lvl;
-	int ret;
-
-	/*
-	 * For poweroff we need to set the UFS device to PowerDown mode.
-	 * Force spm_lvl to ensure that.
-	 */
-	hba->spm_lvl = 5;
-	ret = ufshcd_system_suspend(hba);
-	hba->spm_lvl = spm_lvl;
-	return ret;
-}
-
 #endif /* !CONFIG_PM_SLEEP */
 
 #ifdef CONFIG_PM

@@ -370,7 +347,6 @@ static const struct dev_pm_ops ufshcd_pci_pm_ops = {
 	.resume		= ufshcd_pci_resume,
 	.freeze		= ufshcd_pci_suspend,
 	.thaw		= ufshcd_pci_resume,
-	.poweroff	= ufshcd_pci_poweroff,
 	.restore	= ufshcd_pci_resume,
 #endif
 	SET_RUNTIME_PM_OPS(ufshcd_pci_runtime_suspend,

drivers/scsi/ufs/ufshcd-pltfrm.c +0 -0

index 1a69949..84550dc 100644
@@ -217,6 +217,35 @@ int ufshcd_pltfrm_runtime_idle(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(ufshcd_pltfrm_runtime_idle);
 

drivers/scsi/ufs/ufshcd-pltfrm.c int ufshcd_pltfrm_runtime_idle(struct device *dev) · line 229

Quoted 10 lines

drivers/scsi/ufs/ufshcd-pltfrm.c +10 -0

+int ufshcd_pltfrm_prepare(struct device *dev)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	/*
+	 * SCSI assumes that runtime-pm and system-pm for scsi drivers
+	 * are same. And it doesn't wake up the device for system-suspend
+	 * if it's runtime suspended. But ufs doesn't follow that.
+	 * The rpm-lvl and spm-lvl can be different in ufs.
+	 * Force it to honor system-suspend.

Presumably we could check whether the current power mode is different from the spm_lvl target power mode, and only do this in that case?

Quoted 4 lines

drivers/scsi/ufs/ufshcd-pltfrm.c +4 -0

+	 */
+	scsi_autopm_get_device(hba->sdev_ufs_device);
+	/* Refer ufshcd_pltfrm_resume_early() */
+	pm_runtime_get_noresume(&hba->sdev_ufs_device->sdev_gendev);

drivers/scsi/ufs/ufshcd-pltfrm.c int ufshcd_pltfrm_runtime_idle(struct device *dev) · line 238

Quoted 5 lines

drivers/scsi/ufs/ufshcd-pltfrm.c +5 -0

+	scsi_autopm_put_device(hba->sdev_ufs_device);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ufshcd_pltfrm_prepare);

The PCI driver will need this also, so we need a bus-agnostic version exported from ufshcd.c that all drivers can use, like ufshcd_suspend() etc.

Quoted 4 lines

drivers/scsi/ufs/ufshcd-pltfrm.c +4 -0

+
+int ufshcd_pltfrm_resume_early(struct device *dev)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);

drivers/scsi/ufs/ufshcd-pltfrm.c int ufshcd_pltfrm_runtime_idle(struct device *dev) · line 248

Quoted 6 lines

drivers/scsi/ufs/ufshcd-pltfrm.c +6 -0

+
+	pm_runtime_put_noidle(&hba->sdev_ufs_device->sdev_gendev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ufshcd_pltfrm_resume_early);

Ditto

Quoted 233 lines

drivers/scsi/ufs/ufshcd-pltfrm.c +0 -0

 #endif /* CONFIG_PM */
 
 void ufshcd_pltfrm_shutdown(struct platform_device *pdev)

drivers/scsi/ufs/ufshcd-pltfrm.h +4 -0

index 772a8e8..caf2709 100644
@@ -40,6 +40,8 @@ int ufshcd_pltfrm_resume(struct device *dev);
 int ufshcd_pltfrm_runtime_suspend(struct device *dev);
 int ufshcd_pltfrm_runtime_resume(struct device *dev);
 int ufshcd_pltfrm_runtime_idle(struct device *dev);
+int ufshcd_pltfrm_prepare(struct device *dev);
+int ufshcd_pltfrm_resume_early(struct device *dev);
 
 #else /* !CONFIG_PM */
 

@@ -48,6 +50,8 @@ int ufshcd_pltfrm_runtime_idle(struct device *dev);
 #define ufshcd_pltfrm_runtime_suspend	NULL
 #define ufshcd_pltfrm_runtime_resume	NULL
 #define ufshcd_pltfrm_runtime_idle	NULL
+#define ufshcd_pltfrm_prepare	NULL
+#define ufshcd_pltfrm_resume_early	NULL
 
 #endif /* CONFIG_PM */
 

drivers/scsi/ufs/ufshcd.c +79 -23

index 45624c7..bc96544 100644
@@ -16,6 +16,7 @@
 #include <linux/bitfield.h>
 #include <linux/blk-pm.h>
 #include <linux/blkdev.h>
+#include <scsi/scsi_driver.h>
 #include "ufshcd.h"
 #include "ufs_quirks.h"
 #include "unipro.h"

@@ -78,6 +79,8 @@
 /* Polling time to wait for fDeviceInit */
 #define FDEVICEINIT_COMPL_TIMEOUT 1500 /* millisecs */
 
+#define wlun_dev_to_hba(dv) shost_priv(to_scsi_device(dv)->host)
+
 #define ufshcd_toggle_vreg(_dev, _vreg, _on)				\
 	({                                                              \
 		int _ret;                                               \

@@ -251,6 +254,12 @@ static int ufshcd_wb_toggle_flush_during_h8(struct ufs_hba *hba, bool set);
 static inline int ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool enable);
 static void ufshcd_hba_vreg_set_lpm(struct ufs_hba *hba);
 static void ufshcd_hba_vreg_set_hpm(struct ufs_hba *hba);
+static int ufshcd_wl_runtime_suspend(struct device *dev);
+static int ufshcd_wl_runtime_resume(struct device *dev);
+static int ufshcd_wl_suspend(struct device *dev);
+static int ufshcd_wl_resume(struct device *dev);
+static void ufshcd_wl_shutdown(struct device *dev);
+static int ufshcd_clear_ua_wlun(struct ufs_hba *hba, u8 wlun);
 
 static inline bool ufshcd_valid_tag(struct ufs_hba *hba, int tag)
 {

@@ -1556,7 +1565,7 @@ static ssize_t ufshcd_clkscale_enable_store(struct device *dev,
 	if (value == hba->clk_scaling.is_enabled)
 		goto out;
 
-	pm_runtime_get_sync(hba->dev);
+	scsi_autopm_get_device(hba->sdev_ufs_device);
 	ufshcd_hold(hba, false);
 
 	hba->clk_scaling.is_enabled = value;

@@ -1572,7 +1581,7 @@ static ssize_t ufshcd_clkscale_enable_store(struct device *dev,
 	}
 
 	ufshcd_release(hba);
-	pm_runtime_put_sync(hba->dev);
+	scsi_autopm_put_device(hba->sdev_ufs_device);
 out:
 	up(&hba->host_sem);
 	return err ? err : count;

@@ -2572,6 +2581,17 @@ static inline u16 ufshcd_upiu_wlun_to_scsi_wlun(u8 upiu_wlun_id)
 	return (upiu_wlun_id & ~UFS_UPIU_WLUN_ID) | SCSI_W_LUN_BASE;
 }
 
+static inline bool is_rpmb_wlun(struct scsi_device *sdev)
+{
+	return (sdev->lun == ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_RPMB_WLUN));
+}
+
+static inline bool is_device_wlun(struct scsi_device *sdev)
+{
+	return (sdev->lun ==
+		ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_UFS_DEVICE_WLUN));
+}
+
 static void ufshcd_init_lrb(struct ufs_hba *hba, struct ufshcd_lrb *lrb, int i)
 {
 	struct utp_transfer_cmd_desc *cmd_descp = hba->ucdl_base_addr;

@@ -4808,6 +4828,41 @@ static inline void ufshcd_get_lu_power_on_wp_status(struct ufs_hba *hba,
 }
 
 /**
+ * ufshcd_setup_links - associate link b/w device wlun and other luns
+ * @sdev: pointer to SCSI device
+ * @hba: pointer to ufs hba
+ */
+static void ufshcd_setup_links(struct ufs_hba *hba, struct scsi_device *sdev)
+{
+	struct device_link *link;
+
+	/*
+	 * device wlun is the supplier & rest of the luns are consumers
+	 * This ensures that device wlun suspends after all other luns.
+	 */
+	if (hba->sdev_ufs_device) {
+		link = device_link_add(&sdev->sdev_gendev,
+				       &hba->sdev_ufs_device->sdev_gendev,
+				       DL_FLAG_PM_RUNTIME);
+		if (!link) {
+			dev_err(&sdev->sdev_gendev, "Failed establishing link - %s\n",
+				dev_name(&hba->sdev_ufs_device->sdev_gendev));
+			return;
+		}
+		hba->luns_avail--;
+		/* Ignore REPORT_LUN wlun probing */
+		if (hba->luns_avail != 1)
+			return;
+
+		pm_runtime_put_noidle(&hba->sdev_ufs_device->sdev_gendev);
+		pm_runtime_mark_last_busy(&hba->sdev_ufs_device->sdev_gendev);
+	} else {
+		/* device wlun is probed */
+		hba->luns_avail--;
+	}
+}
+
+/**
  * ufshcd_slave_alloc - handle initial SCSI device configurations
  * @sdev: pointer to SCSI device
  *

@@ -4838,6 +4893,8 @@ static int ufshcd_slave_alloc(struct scsi_device *sdev)
 
 	ufshcd_get_lu_power_on_wp_status(hba, sdev);
 
+	ufshcd_setup_links(hba, sdev);
+
 	return 0;
 }
 

@@ -4984,16 +5041,9 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 			 * solution could be to abort the system suspend if
 			 * UFS device needs urgent BKOPs.
 			 */
-			if (!hba->pm_op_in_progress &&
-			    ufshcd_is_exception_event(lrbp->ucd_rsp_ptr) &&
-			    schedule_work(&hba->eeh_work)) {
-				/*
-				 * Prevent suspend once eeh_work is scheduled
-				 * to avoid deadlock between ufshcd_suspend
-				 * and exception event handler.
-				 */
-				pm_runtime_get_noresume(hba->dev);
-			}
+			if (ufshcd_is_exception_event(lrbp->ucd_rsp_ptr))
+				/* Flushed in suspend */
+				schedule_work(&hba->eeh_work);
 			break;
 		case UPIU_TRANSACTION_REJECT_UPIU:
 			/* TODO: handle Reject UPIU Response */

@@ -5589,8 +5639,8 @@ static void ufshcd_rpm_dev_flush_recheck_work(struct work_struct *work)
 	 * after a certain delay to recheck the threshold by next runtime
 	 * suspend.
 	 */
-	pm_runtime_get_sync(hba->dev);
-	pm_runtime_put_sync(hba->dev);
+	scsi_autopm_get_device(hba->sdev_ufs_device);
+	scsi_autopm_put_device(hba->sdev_ufs_device);
 }
 
 /**

@@ -5607,7 +5657,6 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
 	u32 status = 0;
 	hba = container_of(work, struct ufs_hba, eeh_work);
 
-	pm_runtime_get_sync(hba->dev);
 	ufshcd_scsi_block_requests(hba);
 	err = ufshcd_get_ee_status(hba, &status);
 	if (err) {

@@ -5623,14 +5672,6 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
 
 out:
 	ufshcd_scsi_unblock_requests(hba);
-	/*
-	 * pm_runtime_get_noresume is called while scheduling
-	 * eeh_work to avoid suspend racing with exception work.
-	 * Hence decrement usage counter using pm_runtime_put_noidle
-	 * to allow suspend on completion of exception event handler.
-	 */
-	pm_runtime_put_noidle(hba->dev);
-	pm_runtime_put(hba->dev);
 	return;
 }
 

@@ -7254,6 +7295,15 @@ static int ufshcd_scsi_add_wlus(struct ufs_hba *hba)
 		goto out;
 	}
 	ufshcd_blk_pm_runtime_init(hba->sdev_ufs_device);
+	/*
+	 * A pm_runtime_put_sync is invoked when this device enables blk_pm_runtime
+	 * & would suspend the device-wlun upon timer expiry.
+	 * But suspending device wlun _may_ put the ufs device in the pre-defined
+	 * low power mode (SSU <rpm_lvl>). Probing of other luns may fail then.
+	 * Don't allow this suspend until all the luns have been probed.
+	 * See pm_runtime_mark_last_busy in ufshcd_setup_links.
+	 */
+	pm_runtime_get_noresume(&hba->sdev_ufs_device->sdev_gendev);
 	scsi_device_put(hba->sdev_ufs_device);
 
 	hba->sdev_rpmb = __scsi_add_device(hba->host, 0, 0,

@@ -7417,6 +7467,9 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
 		goto out;
 	}
 
+	hba->luns_avail = desc_buf[DEVICE_DESC_PARAM_NUM_LU] +
+		desc_buf[DEVICE_DESC_PARAM_NUM_WLU];
+
 	ufs_fixup_device_setup(hba);
 
 	ufshcd_wb_probe(hba, desc_buf);

@@ -7747,6 +7800,95 @@ static int ufshcd_device_params_init(struct ufs_hba *hba)
 	return ret;
 }
 
+static int ufshcd_wl_probe(struct device *dev)
+{
+	return is_device_wlun(to_scsi_device(dev)) ? 0 : -ENODEV;

drivers/scsi/ufs/ufshcd.c static int ufshcd_device_params_init(struct ufs_hba *hba) · line 7815

Quoted 10 lines

drivers/scsi/ufs/ufshcd.c +10 -0

+}
+
+static int ufshcd_wl_remove(struct device *dev)
+{
+	return 0;
+}
+
+static const struct dev_pm_ops ufshcd_wl_pm_ops = {
+	SET_RUNTIME_PM_OPS(ufshcd_wl_runtime_suspend, ufshcd_wl_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(ufshcd_wl_suspend, ufshcd_wl_resume)

Here SET_SYSTEM_SLEEP_PM_OPS sets .poweroff to ufshcd_wl_suspend() which is only correct if spm_lvl is 5. We need it to do what ufshcd_wl_shutdown() does, although the PM functions return 'int' whereas ->shutdown() returns 'void', so it cannot use the same prototype i.e.

static int ufshcd_wl_poweroff(struct device *dev)

{
	ufshcd_wl_shutdown(dev);
	return 0;
}

Then,
.suspend = ufshcd_wl_suspend,
.resume = ufshcd_wl_resume,
.freeze = ufshcd_wl_suspend,
.thaw = ufshcd_wl_resume,
.poweroff = ufshcd_wl_poweroff,
.restore = ufshcd_wl_resume,

Quoted 83 lines

drivers/scsi/ufs/ufshcd.c +76 -0

+};
+
+/**
+ * ufs_dev_wlun_template - describes ufs device wlun
+ * ufs-device wlun - used to send pm commands
+ * All luns are consumers of ufs-device wlun.
+ *
+ * Currently, no sd driver is present for wluns.
+ * Hence the no specific pm operations are performed.
+ * With ufs design, SSU should be sent to ufs-device wlun.
+ * Hence register a scsi driver for ufs wluns only.
+ */
+static struct scsi_driver ufs_dev_wlun_template = {
+	.gendrv = {
+		.name = "ufs_device_wlun",
+		.owner = THIS_MODULE,
+		.probe = ufshcd_wl_probe,
+		.remove = ufshcd_wl_remove,
+		.pm = &ufshcd_wl_pm_ops,
+		.shutdown = ufshcd_wl_shutdown,
+	},
+};
+
+static int ufshcd_rpmb_probe(struct device *dev)
+{
+	return is_rpmb_wlun(to_scsi_device(dev)) ? 0 : -ENODEV;
+}
+
+static inline int ufshcd_clear_rpmb_uac(struct ufs_hba *hba)
+{
+	int ret = 0;
+
+	if (!hba->wlun_rpmb_clr_ua)
+		return 0;
+	ret = ufshcd_clear_ua_wlun(hba, UFS_UPIU_RPMB_WLUN);
+	if (!ret)
+		hba->wlun_rpmb_clr_ua = 0;
+	return ret;
+}
+
+static int ufshcd_rpmb_runtime_resume(struct device *dev)
+{
+	struct ufs_hba *hba = wlun_dev_to_hba(dev);
+
+	if (hba->sdev_rpmb)
+		return ufshcd_clear_rpmb_uac(hba);
+	return 0;
+}
+
+static int ufshcd_rpmb_resume(struct device *dev)
+{
+	struct ufs_hba *hba = wlun_dev_to_hba(dev);
+
+	if (hba->sdev_rpmb && !pm_runtime_suspended(dev))
+		return ufshcd_clear_rpmb_uac(hba);
+	return 0;
+}
+
+static const struct dev_pm_ops ufs_rpmb_pm_ops = {
+	SET_RUNTIME_PM_OPS(NULL, ufshcd_rpmb_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(NULL, ufshcd_rpmb_resume)
+};
+
+/**
+ * Describes the ufs rpmb wlun.
+ * Used only to send uac.
+ */
+static struct scsi_driver ufs_rpmb_wlun_template = {
+	.gendrv = {
+		.name = "ufs_rpmb_wlun",
+		.owner = THIS_MODULE,
+		.probe = ufshcd_rpmb_probe,
+		.pm = &ufs_rpmb_pm_ops,
+	},
+};
+
 /**
  * ufshcd_add_lus - probe and add UFS logical units
  * @hba: per-adapter instance

@@ -7755,6 +7897,19 @@ static int ufshcd_add_lus(struct ufs_hba *hba)
 {
 	int ret;
 

drivers/scsi/ufs/ufshcd.c static int ufshcd_add_lus(struct ufs_hba *hba) · line 7905

Quoted 6 lines

drivers/scsi/ufs/ufshcd.c +6 -0

+	ret = scsi_register_driver(&ufs_dev_wlun_template.gendrv);
+	if (ret) {
+		dev_err(hba->dev, "Register device wlun driver failed: %d\n",
+			ret);
+		return ret;
+	}

This is assuming there is only one UFS host controller, which is probably true but not something that we should assume. Moving this to ufshcd_core_init() might also avoid some more of the forward declarations.

Quoted 495 lines

drivers/scsi/ufs/ufshcd.c +223 -74

+
+	ret = scsi_register_driver(&ufs_rpmb_wlun_template.gendrv);
+	if (ret) {
+		dev_err(hba->dev, "Register device wlun driver failed: %d\n",
+			ret);
+		return ret;
+	}
 	/* Add required well known logical units to scsi mid layer */
 	ret = ufshcd_scsi_add_wlus(hba);
 	if (ret)

@@ -7892,6 +8047,7 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool async)
 	ufshcd_set_ufs_dev_active(hba);
 	ufshcd_force_reset_auto_bkops(hba);
 	hba->wlun_dev_clr_ua = true;
+	hba->wlun_rpmb_clr_ua = true;
 
 	/* Gear up to HS gear if supported */
 	if (hba->max_pwr_info.is_valid) {

@@ -7964,6 +8120,7 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 		pm_runtime_put_sync(hba->dev);
 		ufshcd_hba_exit(hba);
 	}
+	hba->init_done = true;
 }
 
 static const struct attribute_group *ufshcd_driver_groups[] = {

@@ -8475,7 +8632,8 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
 	 * handling context.
 	 */
 	hba->host->eh_noresume = 1;
-	ufshcd_clear_ua_wluns(hba);
+	if (hba->wlun_dev_clr_ua)
+		ufshcd_clear_ua_wlun(hba, UFS_UPIU_UFS_DEVICE_WLUN);
 
 	cmd[4] = pwr_mode << 4;
 

@@ -8650,31 +8808,19 @@ static void ufshcd_hba_vreg_set_hpm(struct ufs_hba *hba)
 		ufshcd_setup_hba_vreg(hba, true);
 }
 
-/**
- * ufshcd_suspend - helper function for suspend operations
- * @hba: per adapter instance
- * @pm_op: desired low power operation type
- *
- * This function will try to put the UFS device and link into low power
- * mode based on the "rpm_lvl" (Runtime PM level) or "spm_lvl"
- * (System PM level).
- *
- * If this function is called during shutdown, it will make sure that
- * both UFS device and UFS link is powered off.
- *
- * NOTE: UFS device & link must be active before we enter in this function.
- *
- * Returns 0 for success and non-zero for failure
- */
-static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+static int __ufshcd_wl_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 {
 	int ret = 0;
-	int check_for_bkops;
 	enum ufs_pm_level pm_lvl;
 	enum ufs_dev_pwr_mode req_dev_pwr_mode;
 	enum uic_link_state req_link_state;
 
-	hba->pm_op_in_progress = 1;
+	/*
+	 * Is invoked when the device wlun is added to sysfs
+	 * But by then hba->sdev_ufs_device may not be initialized.
+	 */
+	if (!hba->init_done)
+		return 0;
 	if (!ufshcd_is_shutdown_pm(pm_op)) {
 		pm_lvl = ufshcd_is_runtime_pm(pm_op) ?
 			 hba->rpm_lvl : hba->spm_lvl;

@@ -8690,24 +8836,23 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	 * just gate the clocks.
 	 */
 	ufshcd_hold(hba, false);
-	hba->clk_gating.is_suspended = true;
 
 	if (ufshcd_is_clkscaling_supported(hba))
 		ufshcd_clk_scaling_suspend(hba, true);
 
 	if (req_dev_pwr_mode == UFS_ACTIVE_PWR_MODE &&
 			req_link_state == UIC_LINK_ACTIVE_STATE) {
-		goto disable_clks;
+		goto enable_scaling;
 	}
 
 	if ((req_dev_pwr_mode == hba->curr_dev_pwr_mode) &&
 	    (req_link_state == hba->uic_link_state))
-		goto enable_gating;
+		goto enable_scaling;
 
 	/* UFS device & link must be active before we enter in this function */
 	if (!ufshcd_is_ufs_dev_active(hba) || !ufshcd_is_link_active(hba)) {
 		ret = -EINVAL;
-		goto enable_gating;
+		goto enable_scaling;
 	}
 
 	if (ufshcd_is_runtime_pm(pm_op)) {

@@ -8719,7 +8864,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 			 */
 			ret = ufshcd_urgent_bkops(hba);
 			if (ret)
-				goto enable_gating;
+				goto enable_scaling;
 		} else {
 			/* make sure that auto bkops is disabled */
 			ufshcd_disable_auto_bkops(hba);

@@ -8746,10 +8891,206 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 
 		if (!hba->dev_info.b_rpm_dev_flush_capable) {
 			ret = ufshcd_set_dev_pwr_mode(hba, req_dev_pwr_mode);
-			if (ret)
-				goto enable_gating;
+			if (!ret)
+				goto out;
 		}
 	}
+enable_scaling:
+	if (ufshcd_is_clkscaling_supported(hba))
+		ufshcd_clk_scaling_suspend(hba, false);
+
+	hba->dev_info.b_rpm_dev_flush_capable = false;
+out:
+	if (hba->dev_info.b_rpm_dev_flush_capable) {
+		schedule_delayed_work(&hba->rpm_dev_flush_recheck_work,
+			msecs_to_jiffies(RPM_DEV_FLUSH_RECHECK_WORK_DELAY_MS));
+	}
+	if (ret)
+		ufshcd_update_evt_hist(hba, UFS_EVT_WL_SUSP_ERR, (u32)ret);
+	ufshcd_release(hba);
+	return ret;
+}
+
+static int __ufshcd_wl_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+{
+	int ret = 0;
+
+	if (!hba->init_done)
+		return 0;
+
+	ufshcd_hold(hba, false);
+	if (ufshcd_is_ufs_dev_deepsleep(hba)) {
+		/* The device is in DeepSleep but hba was not suspended */
+		ret = ufshcd_reset_and_restore(hba);
+		if (ret)
+			goto out;
+	}
+
+	if (!ufshcd_is_ufs_dev_active(hba)) {
+		ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE);
+		if (ret)
+			goto out;
+	}
+
+	if (ufshcd_keep_autobkops_enabled_except_suspend(hba))
+		ufshcd_enable_auto_bkops(hba);
+	else
+		/*
+		 * If BKOPs operations are urgently needed at this moment then
+		 * keep auto-bkops enabled or else disable it.
+		 */
+		ufshcd_urgent_bkops(hba);
+
+	if (hba->clk_scaling.is_allowed)
+		ufshcd_resume_clkscaling(hba);
+
+	if (hba->dev_info.b_rpm_dev_flush_capable) {
+		hba->dev_info.b_rpm_dev_flush_capable = false;
+		cancel_delayed_work(&hba->rpm_dev_flush_recheck_work);
+	}
+
+out:
+	if (ret)
+		ufshcd_update_evt_hist(hba, UFS_EVT_WL_RES_ERR, (u32)ret);
+	ufshcd_release(hba);
+	return ret;
+}
+
+static int ufshcd_wl_runtime_suspend(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+	int ret;
+	ktime_t start = ktime_get();
+
+	hba = shost_priv(sdev->host);
+
+	ret = __ufshcd_wl_suspend(hba, UFS_RUNTIME_PM);
+	if (ret)
+		dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__, ret);
+
+	trace_ufshcd_wl_runtime_suspend(dev_name(dev), ret,
+		ktime_to_us(ktime_sub(ktime_get(), start)),
+		hba->curr_dev_pwr_mode, hba->uic_link_state);
+
+	return ret;
+}
+
+static int ufshcd_wl_runtime_resume(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+	int ret = 0;
+	ktime_t start = ktime_get();
+
+	hba = shost_priv(sdev->host);
+
+	ret = __ufshcd_wl_resume(hba, UFS_RUNTIME_PM);
+	if (ret)
+		dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__, ret);
+
+	trace_ufshcd_wl_runtime_resume(dev_name(dev), ret,
+		ktime_to_us(ktime_sub(ktime_get(), start)),
+		hba->curr_dev_pwr_mode, hba->uic_link_state);
+
+	return ret;
+}
+
+static int ufshcd_wl_suspend(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+	int ret;
+	ktime_t start = ktime_get();
+
+	hba = shost_priv(sdev->host);
+	ret = __ufshcd_wl_suspend(hba, UFS_SYSTEM_PM);
+	if (ret)
+		dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__,  ret);
+
+	trace_ufshcd_wl_suspend(dev_name(dev), ret,
+		ktime_to_us(ktime_sub(ktime_get(), start)),
+		hba->curr_dev_pwr_mode, hba->uic_link_state);
+
+	return ret;
+}
+
+static int ufshcd_wl_resume(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+	int ret = 0;
+	ktime_t start = ktime_get();
+
+	if (pm_runtime_suspended(dev))
+		return 0;
+	hba = shost_priv(sdev->host);
+
+	ret = __ufshcd_wl_resume(hba, UFS_SYSTEM_PM);
+	if (ret)
+		dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__, ret);
+
+	trace_ufshcd_wl_resume(dev_name(dev), ret,
+		ktime_to_us(ktime_sub(ktime_get(), start)),
+		hba->curr_dev_pwr_mode, hba->uic_link_state);
+
+	return ret;
+}
+
+static void ufshcd_wl_shutdown(struct device *dev)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ufs_hba *hba;
+
+	hba = shost_priv(sdev->host);
+	scsi_device_quiesce(sdev);
+	shost_for_each_device(sdev, hba->host) {
+		if (sdev == hba->sdev_ufs_device)
+			continue;
+		scsi_device_quiesce(sdev);
+	}
+	__ufshcd_wl_suspend(hba, UFS_SHUTDOWN_PM);
+}
+
+/**
+ * ufshcd_suspend - helper function for suspend operations
+ * @hba: per adapter instance
+ * @pm_op: desired low power operation type
+ *
+ * This function will try to put the UFS link into low power
+ * mode based on the "rpm_lvl" (Runtime PM level) or "spm_lvl"
+ * (System PM level).
+ *
+ * If this function is called during shutdown, it will make sure that
+ * link is powered off.
+ *
+ * Returns 0 for success and non-zero for failure
+ */
+static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
+{
+	int ret = 0;
+	int check_for_bkops;
+	enum ufs_pm_level pm_lvl;
+	enum ufs_dev_pwr_mode req_dev_pwr_mode;
+	enum uic_link_state req_link_state;
+
+	hba->pm_op_in_progress = 1;
+	if (!ufshcd_is_shutdown_pm(pm_op)) {
+		pm_lvl = ufshcd_is_runtime_pm(pm_op) ?
+			 hba->rpm_lvl : hba->spm_lvl;
+		req_dev_pwr_mode = ufs_get_pm_lvl_to_dev_pwr_mode(pm_lvl);
+		req_link_state = ufs_get_pm_lvl_to_link_pwr_state(pm_lvl);
+	} else {
+		req_dev_pwr_mode = UFS_POWERDOWN_PWR_MODE;
+		req_link_state = UIC_LINK_OFF_STATE;
+	}
+
+	/*
+	 * If we can't transition into any of the low power modes
+	 * just gate the clocks.
+	 */
+	ufshcd_hold(hba, false);
+	hba->clk_gating.is_suspended = true;
 
 	/*
 	 * In the case of DeepSleep, the device is expected to remain powered

@@ -8758,9 +9099,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	check_for_bkops = !ufshcd_is_ufs_dev_deepsleep(hba);
 	ret = ufshcd_link_state_transition(hba, req_link_state, check_for_bkops);
 	if (ret)
-		goto set_dev_active;
+		goto enable_gating;
 
-disable_clks:
 	/*
 	 * Call vendor specific suspend callback. As these callbacks may access
 	 * vendor specific host controller register space call them before the

@@ -8790,7 +9130,6 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 	goto out;
 
 set_link_active:
-	ufshcd_vreg_set_hpm(hba);
 	/*
 	 * Device hardware reset is required to exit DeepSleep. Also, for
 	 * DeepSleep, the link is off so host reset and restore will be done

@@ -8804,28 +9143,15 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 		ufshcd_set_link_active(hba);
 	else if (ufshcd_is_link_off(hba))
 		ufshcd_host_reset_and_restore(hba);
-set_dev_active:
 	/* Can also get here needing to exit DeepSleep */
 	if (ufshcd_is_ufs_dev_deepsleep(hba)) {
 		ufshcd_device_reset(hba);
 		ufshcd_host_reset_and_restore(hba);
 	}
-	if (!ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE))
-		ufshcd_disable_auto_bkops(hba);
 enable_gating:
-	if (ufshcd_is_clkscaling_supported(hba))
-		ufshcd_clk_scaling_suspend(hba, false);
-
 	hba->clk_gating.is_suspended = false;
-	hba->dev_info.b_rpm_dev_flush_capable = false;
-	ufshcd_clear_ua_wluns(hba);
 	ufshcd_release(hba);
 out:
-	if (hba->dev_info.b_rpm_dev_flush_capable) {
-		schedule_delayed_work(&hba->rpm_dev_flush_recheck_work,
-			msecs_to_jiffies(RPM_DEV_FLUSH_RECHECK_WORK_DELAY_MS));
-	}
-
 	hba->pm_op_in_progress = 0;
 
 	if (ret)

@@ -8846,10 +9172,8 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 {
 	int ret;
-	enum uic_link_state old_link_state;
 
 	hba->pm_op_in_progress = 1;
-	old_link_state = hba->uic_link_state;
 
 	ufshcd_hba_vreg_set_hpm(hba);
 	ret = ufshcd_vreg_set_hpm(hba);

@@ -8901,43 +9225,14 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 			goto vendor_suspend;
 	}
 
-	if (!ufshcd_is_ufs_dev_active(hba)) {
-		ret = ufshcd_set_dev_pwr_mode(hba, UFS_ACTIVE_PWR_MODE);
-		if (ret)
-			goto set_old_link_state;
-	}
-
-	if (ufshcd_keep_autobkops_enabled_except_suspend(hba))
-		ufshcd_enable_auto_bkops(hba);
-	else
-		/*
-		 * If BKOPs operations are urgently needed at this moment then
-		 * keep auto-bkops enabled or else disable it.
-		 */
-		ufshcd_urgent_bkops(hba);
-
-	hba->clk_gating.is_suspended = false;
-
-	if (ufshcd_is_clkscaling_supported(hba))
-		ufshcd_clk_scaling_suspend(hba, false);
-
 	/* Enable Auto-Hibernate if configured */
 	ufshcd_auto_hibern8_enable(hba);
 
-	if (hba->dev_info.b_rpm_dev_flush_capable) {
-		hba->dev_info.b_rpm_dev_flush_capable = false;
-		cancel_delayed_work(&hba->rpm_dev_flush_recheck_work);
-	}
-
-	ufshcd_clear_ua_wluns(hba);
-
 	/* Schedule clock gating in case of no access to UFS device yet */
 	ufshcd_release(hba);
 
 	goto out;
 
-set_old_link_state:
-	ufshcd_link_state_transition(hba, old_link_state, 0);
 vendor_suspend:
 	ufshcd_vops_suspend(hba, pm_op);
 disable_irq_and_vops_clks:

@@ -9170,6 +9465,8 @@ EXPORT_SYMBOL(ufshcd_shutdown);
 void ufshcd_remove(struct ufs_hba *hba)
 {
 	ufs_bsg_remove(hba);
+	scsi_unregister_driver(&ufs_dev_wlun_template.gendrv);
+	scsi_unregister_driver(&ufs_rpmb_wlun_template.gendrv);
 	ufs_sysfs_remove_nodes(hba->dev);
 	blk_cleanup_queue(hba->tmf_queue);
 	blk_mq_free_tag_set(&hba->tmf_tag_set);

drivers/scsi/ufs/ufshcd.h +5 -0

index ee61f82..9087593 100644
@@ -72,6 +72,8 @@ enum ufs_event_type {
 	UFS_EVT_LINK_STARTUP_FAIL,
 	UFS_EVT_RESUME_ERR,
 	UFS_EVT_SUSPEND_ERR,
+	UFS_EVT_WL_SUSP_ERR,
+	UFS_EVT_WL_RES_ERR,
 
 	/* abnormal events */
 	UFS_EVT_DEV_RESET,

@@ -804,6 +806,7 @@ struct ufs_hba {
 	struct list_head clk_list_head;
 
 	bool wlun_dev_clr_ua;
+	bool wlun_rpmb_clr_ua;
 
 	/* Number of requests aborts */
 	int req_abort_count;

@@ -841,6 +844,8 @@ struct ufs_hba {
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *debugfs_root;
 #endif
+	bool init_done;
+	u32 luns_avail;
 };
 
 /* Returns true if clocks can be gated. Otherwise false */

include/trace/events/ufs.h +20 -0

index e151477..d9d233b 100644
@@ -246,6 +246,26 @@ DEFINE_EVENT(ufshcd_template, ufshcd_init,
 		      int dev_state, int link_state),
 	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
 
+DEFINE_EVENT(ufshcd_template, ufshcd_wl_suspend,
+	     TP_PROTO(const char *dev_name, int err, s64 usecs,
+		      int dev_state, int link_state),
+	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
+
+DEFINE_EVENT(ufshcd_template, ufshcd_wl_resume,
+	     TP_PROTO(const char *dev_name, int err, s64 usecs,
+		      int dev_state, int link_state),
+	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
+
+DEFINE_EVENT(ufshcd_template, ufshcd_wl_runtime_suspend,
+	     TP_PROTO(const char *dev_name, int err, s64 usecs,
+		      int dev_state, int link_state),
+	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
+
+DEFINE_EVENT(ufshcd_template, ufshcd_wl_runtime_resume,
+	     TP_PROTO(const char *dev_name, int err, s64 usecs,
+		      int dev_state, int link_state),
+	     TP_ARGS(dev_name, err, usecs, dev_state, link_state));
+
 TRACE_EVENT(ufshcd_command,
 	TP_PROTO(const char *dev_name, enum ufs_trace_str_t str_t,
 		 unsigned int tag, u32 doorbell, int transfer_len, u32 intr,