mhi: core: add support for MHI to operate on slave mode

MHI host is not always the bus master. Add support to
operate on slave mode.

CRs-Fixed: 1095436
Change-Id: I4af92c8171cf9ba38267afa753cec33f291d55eb
Signed-off-by: Sujeev Dias <sdias@codeaurora.org>

drivers/platform/msm/mhi/mhi.h

@@ -580,11 +580,15 @@ struct mhi_device_ctxt {
 	void *mhi_ipc_log;
 
 	/* Shadow functions since not all device supports runtime pm */
+	int (*bus_master_rt_get)(struct pci_dev *pci_dev);
+	void (*bus_master_rt_put)(struct pci_dev *pci_dev);
 	void (*runtime_get)(struct mhi_device_ctxt *mhi_dev_ctxt);
 	void (*runtime_put)(struct mhi_device_ctxt *mhi_dev_ctxt);
 	void (*assert_wake)(struct mhi_device_ctxt *mhi_dev_ctxt,
 			    bool force_set);
 	void (*deassert_wake)(struct mhi_device_ctxt *mhi_dev_ctxt);
+
+	struct completion cmd_complete;
 };
 
 struct mhi_device_driver {
@@ -687,8 +691,10 @@ void mhi_notify_clients(struct mhi_device_ctxt *mhi_dev_ctxt,
 						enum MHI_CB_REASON reason);
 void mhi_notify_client(struct mhi_client_handle *client_handle,
 		       enum MHI_CB_REASON reason);
-void mhi_runtime_get(struct mhi_device_ctxt *mhi_dev_ctxt);
+void mhi_master_mode_runtime_get(struct mhi_device_ctxt *mhi_dev_ctxt);
-void mhi_runtime_put(struct mhi_device_ctxt *mhi_dev_ctxt);
+void mhi_master_mode_runtime_put(struct mhi_device_ctxt *mhi_dev_ctxt);
+void mhi_slave_mode_runtime_get(struct mhi_device_ctxt *mhi_dev_ctxt);
+void mhi_slave_mode_runtime_put(struct mhi_device_ctxt *mhi_dev_ctxt);
 void mhi_deassert_device_wake(struct mhi_device_ctxt *mhi_dev_ctxt);
 void mhi_assert_device_wake(struct mhi_device_ctxt *mhi_dev_ctxt,
 			    bool force_set);

drivers/platform/msm/mhi/mhi_iface.c

@@ -196,7 +196,7 @@ static int mhi_pci_probe(struct pci_dev *pcie_device,
 	tasklet_init(&mhi_dev_ctxt->ev_task,
 		     mhi_ctrl_ev_task,
 		     (unsigned long)mhi_dev_ctxt);
-
+	init_completion(&mhi_dev_ctxt->cmd_complete);
 	mhi_dev_ctxt->flags.link_up = 1;
 
 	/* Setup bus scale */
@@ -277,8 +277,8 @@ static int mhi_pci_probe(struct pci_dev *pcie_device,
 	/* setup shadow pm functions */
 	mhi_dev_ctxt->assert_wake = mhi_assert_device_wake;
 	mhi_dev_ctxt->deassert_wake = mhi_deassert_device_wake;
-	mhi_dev_ctxt->runtime_get = mhi_runtime_get;
+	mhi_dev_ctxt->runtime_get = mhi_master_mode_runtime_get;
-	mhi_dev_ctxt->runtime_put = mhi_runtime_put;
+	mhi_dev_ctxt->runtime_put = mhi_master_mode_runtime_put;
 
 	mutex_lock(&mhi_dev_ctxt->pm_lock);
 	write_lock_irq(&mhi_dev_ctxt->pm_xfer_lock);

drivers/platform/msm/mhi/mhi_main.c

@@ -27,6 +27,7 @@
 #include "mhi.h"
 #include "mhi_hwio.h"
 #include "mhi_macros.h"
+#include "mhi_bhi.h"
 #include "mhi_trace.h"
 
 static int reset_chan_cmd(struct mhi_device_ctxt *mhi_dev_ctxt,
@@ -1560,17 +1561,27 @@ int mhi_get_epid(struct mhi_client_handle *client_handle)
 	return MHI_EPID;
 }
 
-void mhi_runtime_get(struct mhi_device_ctxt *mhi_dev_ctxt)
+void mhi_master_mode_runtime_get(struct mhi_device_ctxt *mhi_dev_ctxt)
 {
 	pm_runtime_get(&mhi_dev_ctxt->pcie_device->dev);
 }
 
-void mhi_runtime_put(struct mhi_device_ctxt *mhi_dev_ctxt)
+void mhi_master_mode_runtime_put(struct mhi_device_ctxt *mhi_dev_ctxt)
 {
 	pm_runtime_mark_last_busy(&mhi_dev_ctxt->pcie_device->dev);
 	pm_runtime_put_noidle(&mhi_dev_ctxt->pcie_device->dev);
 }
 
+void mhi_slave_mode_runtime_get(struct mhi_device_ctxt *mhi_dev_ctxt)
+{
+	mhi_dev_ctxt->bus_master_rt_get(mhi_dev_ctxt->pcie_device);
+}
+
+void mhi_slave_mode_runtime_put(struct mhi_device_ctxt *mhi_dev_ctxt)
+{
+	mhi_dev_ctxt->bus_master_rt_put(mhi_dev_ctxt->pcie_device);
+}
+
 /*
  * mhi_assert_device_wake - Set WAKE_DB register
  * force_set - if true, will set bit regardless of counts
@@ -1675,6 +1686,120 @@ int mhi_deregister_channel(struct mhi_client_handle *client_handle)
 }
 EXPORT_SYMBOL(mhi_deregister_channel);
 
+int mhi_register_device(struct mhi_device *mhi_device,
+			const char *node_name,
+			unsigned long user_data)
+{
+	const struct device_node *of_node;
+	struct mhi_device_ctxt *mhi_dev_ctxt = NULL, *itr;
+	struct pcie_core_info *core_info;
+	struct pci_dev *pci_dev = mhi_device->pci_dev;
+	u32 domain = pci_domain_nr(pci_dev->bus);
+	u32 bus = pci_dev->bus->number;
+	u32 dev_id = pci_dev->device;
+	u32 slot = PCI_SLOT(pci_dev->devfn);
+	int ret, i;
+
+	of_node = of_parse_phandle(mhi_device->dev->of_node, node_name, 0);
+	if (!of_node)
+		return -EINVAL;
+
+	if (!mhi_device_drv)
+		return -EPROBE_DEFER;
+
+	/* Traverse thru the list */
+	mutex_lock(&mhi_device_drv->lock);
+	list_for_each_entry(itr, &mhi_device_drv->head, node) {
+		struct platform_device *pdev = itr->plat_dev;
+		struct pcie_core_info *core = &itr->core;
+
+		if (pdev->dev.of_node == of_node &&
+		    core->domain == domain &&
+		    core->bus == bus &&
+		    core->dev_id == dev_id &&
+		    core->slot == slot) {
+			mhi_dev_ctxt = itr;
+			break;
+		}
+	}
+	mutex_unlock(&mhi_device_drv->lock);
+
+	/* perhaps we've not probed yet */
+	if (!mhi_dev_ctxt)
+		return -EPROBE_DEFER;
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO,
+		"Registering Domain:%02u Bus:%04u dev:0x%04x slot:%04u\n",
+		domain, bus, dev_id, slot);
+
+	/* Set up pcie dev info */
+	mhi_dev_ctxt->pcie_device = pci_dev;
+	mhi_dev_ctxt->mhi_pm_state = MHI_PM_DISABLE;
+	INIT_WORK(&mhi_dev_ctxt->process_m1_worker, process_m1_transition);
+	mutex_init(&mhi_dev_ctxt->pm_lock);
+	rwlock_init(&mhi_dev_ctxt->pm_xfer_lock);
+	spin_lock_init(&mhi_dev_ctxt->dev_wake_lock);
+	tasklet_init(&mhi_dev_ctxt->ev_task, mhi_ctrl_ev_task,
+		     (unsigned long)mhi_dev_ctxt);
+	init_completion(&mhi_dev_ctxt->cmd_complete);
+	mhi_dev_ctxt->flags.link_up = 1;
+	core_info = &mhi_dev_ctxt->core;
+	core_info->manufact_id = pci_dev->vendor;
+	core_info->pci_master = false;
+
+	/* Go thru resources and set up */
+	for (i = 0; i < ARRAY_SIZE(mhi_device->resources); i++) {
+		const struct resource *res = &mhi_device->resources[i];
+
+		switch (resource_type(res)) {
+		case IORESOURCE_MEM:
+			/* bus master already mapped it */
+			core_info->bar0_base = (void __iomem *)res->start;
+			core_info->bar0_end = (void __iomem *)res->end;
+			mhi_log(mhi_dev_ctxt, MHI_MSG_INFO,
+				"bar mapped to:0x%llx - 0x%llx (virtual)\n",
+				res->start, res->end);
+			break;
+		case IORESOURCE_IRQ:
+			core_info->irq_base = (u32)res->start;
+			core_info->max_nr_msis = (u32)resource_size(res);
+			mhi_log(mhi_dev_ctxt, MHI_MSG_INFO,
+				"irq mapped to: %u size:%u\n",
+				core_info->irq_base,
+				core_info->max_nr_msis);
+			break;
+		};
+	}
+
+	if (!core_info->bar0_base || !core_info->irq_base)
+		return -EINVAL;
+
+	mhi_dev_ctxt->bus_master_rt_get = mhi_device->pm_runtime_get;
+	mhi_dev_ctxt->bus_master_rt_put = mhi_device->pm_runtime_noidle;
+	if (!mhi_dev_ctxt->bus_master_rt_get ||
+	    !mhi_dev_ctxt->bus_master_rt_put)
+		return -EINVAL;
+
+	ret = mhi_ctxt_init(mhi_dev_ctxt);
+	if (ret) {
+		mhi_log(mhi_dev_ctxt, MHI_MSG_ERROR,
+			"MHI Initialization failed, ret %d\n", ret);
+		return ret;
+	}
+	mhi_init_debugfs(mhi_dev_ctxt);
+
+	/* setup shadow pm functions */
+	mhi_dev_ctxt->assert_wake = mhi_assert_device_wake;
+	mhi_dev_ctxt->deassert_wake = mhi_deassert_device_wake;
+	mhi_dev_ctxt->runtime_get = mhi_slave_mode_runtime_get;
+	mhi_dev_ctxt->runtime_put = mhi_slave_mode_runtime_put;
+	mhi_device->mhi_dev_ctxt = mhi_dev_ctxt;
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Exit success\n");
+
+	return 0;
+}
+EXPORT_SYMBOL(mhi_register_device);
+
 void mhi_process_db_brstmode(struct mhi_device_ctxt *mhi_dev_ctxt,
 			     void __iomem *io_addr,
 			     uintptr_t chan,

drivers/platform/msm/mhi/mhi_pm.c

@@ -20,6 +20,7 @@
 #include "mhi_sys.h"
 #include "mhi.h"
 #include "mhi_hwio.h"
+#include "mhi_bhi.h"
 
 /* Write only sysfs attributes */
 static DEVICE_ATTR(MHI_M0, S_IWUSR, NULL, sysfs_init_m0);
@@ -57,14 +58,12 @@ int mhi_pci_suspend(struct device *dev)
 	return r;
 }
 
-int mhi_runtime_suspend(struct device *dev)
+static int mhi_pm_initiate_m3(struct mhi_device_ctxt *mhi_dev_ctxt,
+			      bool force_m3)
 {
 	int r = 0;
-	struct mhi_device_ctxt *mhi_dev_ctxt = dev_get_drvdata(dev);
 
-	mutex_lock(&mhi_dev_ctxt->pm_lock);
 	read_lock_bh(&mhi_dev_ctxt->pm_xfer_lock);
-
 	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO,
 		"Entered with State:0x%x %s\n",
 		mhi_dev_ctxt->mhi_pm_state,
@@ -74,17 +73,16 @@ int mhi_runtime_suspend(struct device *dev)
 	if (mhi_dev_ctxt->mhi_pm_state == MHI_PM_DISABLE ||
 	   mhi_dev_ctxt->mhi_pm_state == MHI_PM_M3) {
 		mhi_log(mhi_dev_ctxt, MHI_MSG_INFO,
-			"Already in active state, exiting\n");
+			"Already in M3 State\n");
 		read_unlock_bh(&mhi_dev_ctxt->pm_xfer_lock);
-		mutex_unlock(&mhi_dev_ctxt->pm_lock);
 		return 0;
 	}
 
-	if (unlikely(atomic_read(&mhi_dev_ctxt->counters.device_wake))) {
+	if (unlikely(atomic_read(&mhi_dev_ctxt->counters.device_wake) &&
+		     force_m3 == false)){
 		mhi_log(mhi_dev_ctxt, MHI_MSG_INFO,
-			"Busy, Aborting Runtime Suspend\n");
+			"Busy, Aborting M3\n");
 		read_unlock_bh(&mhi_dev_ctxt->pm_xfer_lock);
-		mutex_unlock(&mhi_dev_ctxt->pm_lock);
 		return -EBUSY;
 	}
 
@@ -98,8 +96,7 @@ int mhi_runtime_suspend(struct device *dev)
 		mhi_log(mhi_dev_ctxt, MHI_MSG_CRITICAL,
 			"Failed to get M0||M1 event, timeout, current state:%s\n",
 			TO_MHI_STATE_STR(mhi_dev_ctxt->mhi_state));
-		r = -EIO;
+		return -EIO;
-		goto rpm_suspend_exit;
 	}
 
 	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Allowing M3 State\n");
@@ -116,20 +113,66 @@ int mhi_runtime_suspend(struct device *dev)
 		mhi_log(mhi_dev_ctxt, MHI_MSG_CRITICAL,
 			"Failed to get M3 event, timeout, current state:%s\n",
 			TO_MHI_STATE_STR(mhi_dev_ctxt->mhi_state));
-		r = -EIO;
+		return -EIO;
-		goto rpm_suspend_exit;
 	}
 
+	return 0;
+}
+
+static int mhi_pm_initiate_m0(struct mhi_device_ctxt *mhi_dev_ctxt)
+{
+	int r;
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO,
+		"Entered with State:0x%x %s\n",
+		mhi_dev_ctxt->mhi_pm_state,
+		TO_MHI_STATE_STR(mhi_dev_ctxt->mhi_state));
+
+	write_lock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+	mhi_dev_ctxt->mhi_pm_state = MHI_PM_M3_EXIT;
+	write_unlock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+
+	/* Set and wait for M0 Event */
+	write_lock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+	mhi_set_m_state(mhi_dev_ctxt, MHI_STATE_M0);
+	write_unlock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+	r = wait_event_timeout(*mhi_dev_ctxt->mhi_ev_wq.m0_event,
+			       mhi_dev_ctxt->mhi_state == MHI_STATE_M0 ||
+			       mhi_dev_ctxt->mhi_state == MHI_STATE_M1,
+			       msecs_to_jiffies(MHI_MAX_RESUME_TIMEOUT));
+	if (!r) {
+		mhi_log(mhi_dev_ctxt, MHI_MSG_ERROR,
+			"Failed to get M0 event, timeout\n");
+		r = -EIO;
+	} else
+		r = 0;
+
+	return r;
+}
+
+int mhi_runtime_suspend(struct device *dev)
+{
+	int r = 0;
+	struct mhi_device_ctxt *mhi_dev_ctxt = dev_get_drvdata(dev);
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Enter\n");
+
+	mutex_lock(&mhi_dev_ctxt->pm_lock);
+	r = mhi_pm_initiate_m3(mhi_dev_ctxt, false);
+	if (r) {
+		mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "abort due to ret:%d\n", r);
+		mutex_unlock(&mhi_dev_ctxt->pm_lock);
+		return r;
+	}
 	r = mhi_turn_off_pcie_link(mhi_dev_ctxt);
 	if (r) {
 		mhi_log(mhi_dev_ctxt, MHI_MSG_ERROR,
-			"Failed to Turn off link ret:%d\n",
+			"Failed to Turn off link ret:%d\n", r);
-			r);
 	}
 
-rpm_suspend_exit:
-	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Exited\n");
 	mutex_unlock(&mhi_dev_ctxt->pm_lock);
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Exited with ret:%d\n", r);
+
 	return r;
 }
 
@@ -167,32 +210,10 @@ int mhi_runtime_resume(struct device *dev)
 
 	/* turn on link */
 	r = mhi_turn_on_pcie_link(mhi_dev_ctxt);
-	if (r) {
+	if (r)
-		mhi_log(mhi_dev_ctxt, MHI_MSG_CRITICAL,
-			"Failed to resume link\n");
 		goto rpm_resume_exit;
-	}
-
-	write_lock_irq(&mhi_dev_ctxt->pm_xfer_lock);
-	mhi_dev_ctxt->mhi_pm_state = MHI_PM_M3_EXIT;
-	write_unlock_irq(&mhi_dev_ctxt->pm_xfer_lock);
-
-	/* Set and wait for M0 Event */
-	write_lock_irq(&mhi_dev_ctxt->pm_xfer_lock);
-	mhi_set_m_state(mhi_dev_ctxt, MHI_STATE_M0);
-	write_unlock_irq(&mhi_dev_ctxt->pm_xfer_lock);
-	r = wait_event_timeout(*mhi_dev_ctxt->mhi_ev_wq.m0_event,
-			       mhi_dev_ctxt->mhi_state == MHI_STATE_M0 ||
-			       mhi_dev_ctxt->mhi_state == MHI_STATE_M1,
-			       msecs_to_jiffies(MHI_MAX_RESUME_TIMEOUT));
-	if (!r) {
-		mhi_log(mhi_dev_ctxt, MHI_MSG_ERROR,
-			"Failed to get M0 event, timeout\n");
-		r = -EIO;
-		goto rpm_resume_exit;
-	}
-	r = 0; /* no errors */
 
+	r = mhi_pm_initiate_m0(mhi_dev_ctxt);
 rpm_resume_exit:
 	mutex_unlock(&mhi_dev_ctxt->pm_lock);
 	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Exited with :%d\n", r);
@@ -216,6 +237,97 @@ int mhi_pci_resume(struct device *dev)
 	return r;
 }
 
+static int mhi_pm_slave_mode_power_on(struct mhi_device_ctxt *mhi_dev_ctxt)
+{
+	int ret_val;
+	u32 timeout = mhi_dev_ctxt->poll_reset_timeout_ms;
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Entered\n");
+	mutex_lock(&mhi_dev_ctxt->pm_lock);
+	write_lock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+	mhi_dev_ctxt->mhi_pm_state = MHI_PM_POR;
+	ret_val = set_mhi_base_state(mhi_dev_ctxt);
+	write_unlock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+
+	if (ret_val) {
+		mhi_log(mhi_dev_ctxt, MHI_MSG_ERROR,
+			"Error Setting MHI Base State %d\n", ret_val);
+		goto unlock_pm_lock;
+	}
+
+	if (mhi_dev_ctxt->base_state != STATE_TRANSITION_BHI) {
+		ret_val = -EIO;
+		mhi_log(mhi_dev_ctxt, MHI_MSG_ERROR,
+			"Invalid Base State, cur_state:%s\n",
+			state_transition_str(mhi_dev_ctxt->base_state));
+		goto unlock_pm_lock;
+	}
+
+	reinit_completion(&mhi_dev_ctxt->cmd_complete);
+	init_mhi_base_state(mhi_dev_ctxt);
+
+	/*
+	 * Keep wake in Active until AMSS, @ AMSS we will
+	 * decrement counts
+	 */
+	read_lock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+	mhi_dev_ctxt->assert_wake(mhi_dev_ctxt, false);
+	read_unlock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+
+	ret_val = wait_for_completion_timeout(&mhi_dev_ctxt->cmd_complete,
+					      msecs_to_jiffies(timeout));
+	if (!ret_val || mhi_dev_ctxt->dev_exec_env != MHI_EXEC_ENV_AMSS)
+		ret_val = -EIO;
+	else
+		ret_val = 0;
+
+	if (ret_val) {
+		read_lock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+		mhi_dev_ctxt->deassert_wake(mhi_dev_ctxt);
+		read_unlock_irq(&mhi_dev_ctxt->pm_xfer_lock);
+	}
+
+unlock_pm_lock:
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Exit with ret:%d\n", ret_val);
+	mutex_unlock(&mhi_dev_ctxt->pm_lock);
+	return ret_val;
+}
+
+static int mhi_pm_slave_mode_suspend(struct mhi_device_ctxt *mhi_dev_ctxt)
+{
+	int r;
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Entered\n");
+	mutex_lock(&mhi_dev_ctxt->pm_lock);
+
+	r = mhi_pm_initiate_m3(mhi_dev_ctxt, false);
+	if (r)
+		mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "abort due to ret:%d\n", r);
+	mutex_unlock(&mhi_dev_ctxt->pm_lock);
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Exit with ret:%d\n", r);
+
+	return r;
+}
+
+static int mhi_pm_slave_mode_resume(struct mhi_device_ctxt *mhi_dev_ctxt)
+{
+	int r;
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Entered\n");
+	mutex_lock(&mhi_dev_ctxt->pm_lock);
+
+	r = mhi_pm_initiate_m0(mhi_dev_ctxt);
+	if (r)
+		mhi_log(mhi_dev_ctxt, MHI_MSG_ERROR,
+			"M3 exit failed ret:%d\n", r);
+	mutex_unlock(&mhi_dev_ctxt->pm_lock);
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Exit with ret:%d\n", r);
+
+	return r;
+}
+
 int mhi_init_pm_sysfs(struct device *dev)
 {
 	return sysfs_create_group(&dev->kobj, &mhi_attribute_group);
@@ -344,3 +456,30 @@ exit:
 	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO, "Exited...\n");
 	return r;
 }
+
+int mhi_pm_control_device(struct mhi_device *mhi_device,
+		       enum mhi_dev_ctrl ctrl)
+{
+	struct mhi_device_ctxt *mhi_dev_ctxt = mhi_device->mhi_dev_ctxt;
+
+	if (!mhi_dev_ctxt)
+		return -EINVAL;
+
+	mhi_log(mhi_dev_ctxt, MHI_MSG_INFO,
+		"Entered with cmd:%d\n", ctrl);
+
+	switch (ctrl) {
+	case MHI_DEV_CTRL_INIT:
+		return bhi_probe(mhi_dev_ctxt);
+	case MHI_DEV_CTRL_POWER_ON:
+		return mhi_pm_slave_mode_power_on(mhi_dev_ctxt);
+	case MHI_DEV_CTRL_SUSPEND:
+		return mhi_pm_slave_mode_suspend(mhi_dev_ctxt);
+	case MHI_DEV_CTRL_RESUME:
+		return mhi_pm_slave_mode_resume(mhi_dev_ctxt);
+	default:
+		break;
+	}
+	return -EINVAL;
+}
+EXPORT_SYMBOL(mhi_pm_control_device);

drivers/platform/msm/mhi/mhi_states.c

@@ -524,6 +524,7 @@ static int process_amss_transition(
 	read_lock_bh(&mhi_dev_ctxt->pm_xfer_lock);
 	ring_all_ev_dbs(mhi_dev_ctxt);
 	read_unlock_bh(&mhi_dev_ctxt->pm_xfer_lock);
+	complete(&mhi_dev_ctxt->cmd_complete);
 
 	/*
 	 * runtime_allow will decrement usage_count, counts were

include/linux/msm_mhi.h

@@ -18,6 +18,7 @@
 #define MHI_MAX_MTU        0xFFFF
 
 struct mhi_client_config;
+struct mhi_device_ctxt;
 
 enum MHI_CLIENT_CHANNEL {
 	MHI_CLIENT_LOOPBACK_OUT = 0,
@@ -71,11 +72,11 @@ enum MHI_CLIENT_CHANNEL {
 };
 
 enum MHI_CB_REASON {
-	MHI_CB_XFER = 0x0,
+	MHI_CB_XFER,
-	MHI_CB_MHI_DISABLED = 0x4,
+	MHI_CB_MHI_DISABLED,
-	MHI_CB_MHI_ENABLED = 0x8,
+	MHI_CB_MHI_ENABLED,
-	MHI_CB_CHAN_RESET_COMPLETE = 0x10,
+	MHI_CB_MHI_SHUTDOWN,
-	MHI_CB_reserved = 0x80000000,
+	MHI_CB_SYS_ERROR,
 };
 
 enum MHI_FLAGS {
@@ -122,6 +123,35 @@ struct __packed bhi_vec_entry {
 	u64 size;
 };
 
+/**
+ * struct mhi_device - IO resources for MHI
+ * @dev: device node points to of_node
+ * @pdev: pci device node
+ * @resource: bar memory space and IRQ resources
+ * @pm_runtime_get: fp for bus masters rpm pm_runtime_get
+ * @pm_runtime_noidle: fp for bus masters rpm pm_runtime_noidle
+ * @mhi_dev_ctxt: private data for host
+ */
+struct mhi_device {
+	struct device *dev;
+	struct pci_dev *pci_dev;
+	struct resource resources[2];
+	int (*pm_runtime_get)(struct pci_dev *pci_dev);
+	void (*pm_runtime_noidle)(struct pci_dev *pci_dev);
+	struct mhi_device_ctxt *mhi_dev_ctxt;
+};
+
+enum mhi_dev_ctrl {
+	MHI_DEV_CTRL_INIT,
+	MHI_DEV_CTRL_DE_INIT,
+	MHI_DEV_CTRL_SUSPEND,
+	MHI_DEV_CTRL_RESUME,
+	MHI_DEV_CTRL_POWER_OFF,
+	MHI_DEV_CTRL_POWER_ON,
+	MHI_DEV_CTRL_RAM_DUMP,
+	MHI_DEV_CTRL_NOTIFY_LINK_ERROR,
+};
+
 /**
  * mhi_is_device_ready - Check if MHI is ready to register clients
  *
@@ -133,6 +163,27 @@ struct __packed bhi_vec_entry {
 bool mhi_is_device_ready(const struct device * const dev,
 			 const char *node_name);
 
+/**
+ * mhi_resgister_device - register hardware resources with MHI
+ *
+ * @mhi_device: resources to be used
+ * @node_name: DT node name
+ * @userdata: cb data for client
+ * @Return 0 on success
+ */
+int mhi_register_device(struct mhi_device *mhi_device,
+			const char *node_name,
+			unsigned long user_data);
+
+/**
+ * mhi_pm_control_device - power management control api
+ * @mhi_device: registered device structure
+ * @ctrl: specific command
+ * @Return 0 on success
+ */
+int mhi_pm_control_device(struct mhi_device *mhi_device,
+			  enum mhi_dev_ctrl ctrl);
+
 /**
  * mhi_deregister_channel - de-register callbacks from MHI
  *