--- zzzz-none-000/linux-3.10.107/drivers/misc/mei/bus.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/drivers/misc/mei/bus.c	2021-02-04 17:41:59.000000000 +0000
@@ -22,505 +22,987 @@
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/interrupt.h>
-#include <linux/pci.h>
 #include <linux/mei_cl_bus.h>
 
 #include "mei_dev.h"
-#include "hw-me.h"
 #include "client.h"
 
 #define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
 #define to_mei_cl_device(d) container_of(d, struct mei_cl_device, dev)
 
-static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
+/**
+ * __mei_cl_send - internal client send (write)
+ *
+ * @cl: host client
+ * @buf: buffer to send
+ * @length: buffer length
+ * @blocking: wait for write completion
+ *
+ * Return: written size bytes or < 0 on error
+ */
+ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
+			bool blocking)
 {
-	struct mei_cl_device *device = to_mei_cl_device(dev);
-	struct mei_cl_driver *driver = to_mei_cl_driver(drv);
-	const struct mei_cl_device_id *id;
-
-	if (!device)
-		return 0;
+	struct mei_device *bus;
+	struct mei_cl_cb *cb = NULL;
+	ssize_t rets;
 
-	if (!driver || !driver->id_table)
-		return 0;
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
 
-	id = driver->id_table;
+	bus = cl->dev;
 
-	while (id->name[0]) {
-		if (!strcmp(dev_name(dev), id->name))
-			return 1;
+	mutex_lock(&bus->device_lock);
+	if (bus->dev_state != MEI_DEV_ENABLED) {
+		rets = -ENODEV;
+		goto out;
+	}
 
-		id++;
+	if (!mei_cl_is_connected(cl)) {
+		rets = -ENODEV;
+		goto out;
 	}
 
-	return 0;
-}
+	/* Check if we have an ME client device */
+	if (!mei_me_cl_is_active(cl->me_cl)) {
+		rets = -ENOTTY;
+		goto out;
+	}
 
-static int mei_cl_device_probe(struct device *dev)
-{
-	struct mei_cl_device *device = to_mei_cl_device(dev);
-	struct mei_cl_driver *driver;
-	struct mei_cl_device_id id;
+	if (length > mei_cl_mtu(cl)) {
+		rets = -EFBIG;
+		goto out;
+	}
 
-	if (!device)
-		return 0;
+	cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, NULL);
+	if (!cb) {
+		rets = -ENOMEM;
+		goto out;
+	}
 
-	driver = to_mei_cl_driver(dev->driver);
-	if (!driver || !driver->probe)
-		return -ENODEV;
+	memcpy(cb->buf.data, buf, length);
 
-	dev_dbg(dev, "Device probe\n");
+	rets = mei_cl_write(cl, cb, blocking);
 
-	strlcpy(id.name, dev_name(dev), sizeof(id.name));
+out:
+	mutex_unlock(&bus->device_lock);
+	if (rets < 0)
+		mei_io_cb_free(cb);
 
-	return driver->probe(device, &id);
+	return rets;
 }
 
-static int mei_cl_device_remove(struct device *dev)
+/**
+ * __mei_cl_recv - internal client receive (read)
+ *
+ * @cl: host client
+ * @buf: buffer to receive
+ * @length: buffer length
+ *
+ * Return: read size in bytes of < 0 on error
+ */
+ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 {
-	struct mei_cl_device *device = to_mei_cl_device(dev);
-	struct mei_cl_driver *driver;
+	struct mei_device *bus;
+	struct mei_cl_cb *cb;
+	size_t r_length;
+	ssize_t rets;
 
-	if (!device || !dev->driver)
-		return 0;
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	bus = cl->dev;
 
-	if (device->event_cb) {
-		device->event_cb = NULL;
-		cancel_work_sync(&device->event_work);
+	mutex_lock(&bus->device_lock);
+	if (bus->dev_state != MEI_DEV_ENABLED) {
+		rets = -ENODEV;
+		goto out;
 	}
 
-	driver = to_mei_cl_driver(dev->driver);
-	if (!driver->remove) {
-		dev->driver = NULL;
+	cb = mei_cl_read_cb(cl, NULL);
+	if (cb)
+		goto copy;
 
-		return 0;
-	}
+	rets = mei_cl_read_start(cl, length, NULL);
+	if (rets && rets != -EBUSY)
+		goto out;
 
-	return driver->remove(device);
-}
+	/* wait on event only if there is no other waiter */
+	if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) {
 
-static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
-			     char *buf)
-{
-	int len;
+		mutex_unlock(&bus->device_lock);
 
-	len = snprintf(buf, PAGE_SIZE, "mei:%s\n", dev_name(dev));
+		if (wait_event_interruptible(cl->rx_wait,
+				(!list_empty(&cl->rd_completed)) ||
+				(!mei_cl_is_connected(cl)))) {
 
-	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
-}
+			if (signal_pending(current))
+				return -EINTR;
+			return -ERESTARTSYS;
+		}
 
-static struct device_attribute mei_cl_dev_attrs[] = {
-	__ATTR_RO(modalias),
-	__ATTR_NULL,
-};
+		mutex_lock(&bus->device_lock);
 
-static int mei_cl_uevent(struct device *dev, struct kobj_uevent_env *env)
-{
-	if (add_uevent_var(env, "MODALIAS=mei:%s", dev_name(dev)))
-		return -ENOMEM;
+		if (!mei_cl_is_connected(cl)) {
+			rets = -ENODEV;
+			goto out;
+		}
+	}
 
-	return 0;
-}
+	cb = mei_cl_read_cb(cl, NULL);
+	if (!cb) {
+		rets = 0;
+		goto out;
+	}
 
-static struct bus_type mei_cl_bus_type = {
-	.name		= "mei",
-	.dev_attrs	= mei_cl_dev_attrs,
-	.match		= mei_cl_device_match,
-	.probe		= mei_cl_device_probe,
-	.remove		= mei_cl_device_remove,
-	.uevent		= mei_cl_uevent,
-};
+copy:
+	if (cb->status) {
+		rets = cb->status;
+		goto free;
+	}
 
-static void mei_cl_dev_release(struct device *dev)
-{
-	kfree(to_mei_cl_device(dev));
-}
+	r_length = min_t(size_t, length, cb->buf_idx);
+	memcpy(buf, cb->buf.data, r_length);
+	rets = r_length;
 
-static struct device_type mei_cl_device_type = {
-	.release	= mei_cl_dev_release,
-};
+free:
+	mei_io_cb_free(cb);
+out:
+	mutex_unlock(&bus->device_lock);
 
-static struct mei_cl *mei_bus_find_mei_cl_by_uuid(struct mei_device *dev,
-						uuid_le uuid)
+	return rets;
+}
+
+/**
+ * mei_cldev_send - me device send  (write)
+ *
+ * @cldev: me client device
+ * @buf: buffer to send
+ * @length: buffer length
+ *
+ * Return: written size in bytes or < 0 on error
+ */
+ssize_t mei_cldev_send(struct mei_cl_device *cldev, u8 *buf, size_t length)
 {
-	struct mei_cl *cl, *next;
+	struct mei_cl *cl = cldev->cl;
 
-	list_for_each_entry_safe(cl, next, &dev->device_list, device_link) {
-		if (!uuid_le_cmp(uuid, cl->device_uuid))
-			return cl;
-	}
+	if (cl == NULL)
+		return -ENODEV;
 
-	return NULL;
+	return __mei_cl_send(cl, buf, length, 1);
 }
-struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
-					uuid_le uuid, char *name,
-					struct mei_cl_ops *ops)
+EXPORT_SYMBOL_GPL(mei_cldev_send);
+
+/**
+ * mei_cldev_recv - client receive (read)
+ *
+ * @cldev: me client device
+ * @buf: buffer to receive
+ * @length: buffer length
+ *
+ * Return: read size in bytes of < 0 on error
+ */
+ssize_t mei_cldev_recv(struct mei_cl_device *cldev, u8 *buf, size_t length)
 {
-	struct mei_cl_device *device;
-	struct mei_cl *cl;
-	int status;
+	struct mei_cl *cl = cldev->cl;
 
-	cl = mei_bus_find_mei_cl_by_uuid(dev, uuid);
 	if (cl == NULL)
-		return NULL;
+		return -ENODEV;
 
-	device = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL);
-	if (!device)
-		return NULL;
+	return __mei_cl_recv(cl, buf, length);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_recv);
 
-	device->cl = cl;
-	device->ops = ops;
+/**
+ * mei_cl_bus_event_work  - dispatch rx event for a bus device
+ *    and schedule new work
+ *
+ * @work: work
+ */
+static void mei_cl_bus_event_work(struct work_struct *work)
+{
+	struct mei_cl_device *cldev;
+	struct mei_device *bus;
 
-	device->dev.parent = &dev->pdev->dev;
-	device->dev.bus = &mei_cl_bus_type;
-	device->dev.type = &mei_cl_device_type;
-
-	dev_set_name(&device->dev, "%s", name);
-
-	status = device_register(&device->dev);
-	if (status) {
-		dev_err(&dev->pdev->dev, "Failed to register MEI device\n");
-		kfree(device);
-		return NULL;
-	}
+	cldev = container_of(work, struct mei_cl_device, event_work);
 
-	cl->device = device;
+	bus = cldev->bus;
 
-	dev_dbg(&device->dev, "client %s registered\n", name);
+	if (cldev->event_cb)
+		cldev->event_cb(cldev, cldev->events, cldev->event_context);
 
-	return device;
-}
-EXPORT_SYMBOL_GPL(mei_cl_add_device);
+	cldev->events = 0;
 
-void mei_cl_remove_device(struct mei_cl_device *device)
-{
-	device_unregister(&device->dev);
+	/* Prepare for the next read */
+	if (cldev->events_mask & BIT(MEI_CL_EVENT_RX)) {
+		mutex_lock(&bus->device_lock);
+		mei_cl_read_start(cldev->cl, 0, NULL);
+		mutex_unlock(&bus->device_lock);
+	}
 }
-EXPORT_SYMBOL_GPL(mei_cl_remove_device);
 
-int __mei_cl_driver_register(struct mei_cl_driver *driver, struct module *owner)
+/**
+ * mei_cl_bus_notify_event - schedule notify cb on bus client
+ *
+ * @cl: host client
+ */
+void mei_cl_bus_notify_event(struct mei_cl *cl)
 {
-	int err;
+	struct mei_cl_device *cldev = cl->cldev;
 
-	driver->driver.name = driver->name;
-	driver->driver.owner = owner;
-	driver->driver.bus = &mei_cl_bus_type;
+	if (!cldev || !cldev->event_cb)
+		return;
 
-	err = driver_register(&driver->driver);
-	if (err)
-		return err;
+	if (!(cldev->events_mask & BIT(MEI_CL_EVENT_NOTIF)))
+		return;
 
-	pr_debug("mei: driver [%s] registered\n", driver->driver.name);
+	if (!cl->notify_ev)
+		return;
 
-	return 0;
-}
-EXPORT_SYMBOL_GPL(__mei_cl_driver_register);
+	set_bit(MEI_CL_EVENT_NOTIF, &cldev->events);
 
-void mei_cl_driver_unregister(struct mei_cl_driver *driver)
-{
-	driver_unregister(&driver->driver);
+	schedule_work(&cldev->event_work);
 
-	pr_debug("mei: driver [%s] unregistered\n", driver->driver.name);
+	cl->notify_ev = false;
 }
-EXPORT_SYMBOL_GPL(mei_cl_driver_unregister);
 
-static int ___mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
-			bool blocking)
+/**
+ * mei_cl_bus_rx_event  - schedule rx evenet
+ *
+ * @cl: host client
+ */
+void mei_cl_bus_rx_event(struct mei_cl *cl)
 {
-	struct mei_device *dev;
-	struct mei_cl_cb *cb;
-	int id;
-	int rets;
+	struct mei_cl_device *cldev = cl->cldev;
 
-	if (WARN_ON(!cl || !cl->dev))
-		return -ENODEV;
+	if (!cldev || !cldev->event_cb)
+		return;
 
-	dev = cl->dev;
+	if (!(cldev->events_mask & BIT(MEI_CL_EVENT_RX)))
+		return;
 
-	if (cl->state != MEI_FILE_CONNECTED)
-		return -ENODEV;
+	set_bit(MEI_CL_EVENT_RX, &cldev->events);
 
-	/* Check if we have an ME client device */
-	id = mei_me_cl_by_id(dev, cl->me_client_id);
-	if (id < 0)
-		return -ENODEV;
+	schedule_work(&cldev->event_work);
+}
 
-	if (length > dev->me_clients[id].props.max_msg_length)
-		return -EINVAL;
+/**
+ * mei_cldev_register_event_cb - register event callback
+ *
+ * @cldev: me client devices
+ * @event_cb: callback function
+ * @events_mask: requested events bitmask
+ * @context: driver context data
+ *
+ * Return: 0 on success
+ *         -EALREADY if an callback is already registered
+ *         <0 on other errors
+ */
+int mei_cldev_register_event_cb(struct mei_cl_device *cldev,
+				unsigned long events_mask,
+				mei_cldev_event_cb_t event_cb, void *context)
+{
+	struct mei_device *bus = cldev->bus;
+	int ret;
 
-	cb = mei_io_cb_init(cl, NULL);
-	if (!cb)
-		return -ENOMEM;
+	if (cldev->event_cb)
+		return -EALREADY;
 
-	rets = mei_io_cb_alloc_req_buf(cb, length);
-	if (rets < 0) {
-		mei_io_cb_free(cb);
-		return rets;
+	cldev->events = 0;
+	cldev->events_mask = events_mask;
+	cldev->event_cb = event_cb;
+	cldev->event_context = context;
+	INIT_WORK(&cldev->event_work, mei_cl_bus_event_work);
+
+	if (cldev->events_mask & BIT(MEI_CL_EVENT_RX)) {
+		mutex_lock(&bus->device_lock);
+		ret = mei_cl_read_start(cldev->cl, 0, NULL);
+		mutex_unlock(&bus->device_lock);
+		if (ret && ret != -EBUSY)
+			return ret;
+	}
+
+	if (cldev->events_mask & BIT(MEI_CL_EVENT_NOTIF)) {
+		mutex_lock(&bus->device_lock);
+		ret = mei_cl_notify_request(cldev->cl, NULL, event_cb ? 1 : 0);
+		mutex_unlock(&bus->device_lock);
+		if (ret)
+			return ret;
 	}
 
-	memcpy(cb->request_buffer.data, buf, length);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_register_event_cb);
+
+/**
+ * mei_cldev_get_drvdata - driver data getter
+ *
+ * @cldev: mei client device
+ *
+ * Return: driver private data
+ */
+void *mei_cldev_get_drvdata(const struct mei_cl_device *cldev)
+{
+	return dev_get_drvdata(&cldev->dev);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_get_drvdata);
+
+/**
+ * mei_cldev_set_drvdata - driver data setter
+ *
+ * @cldev: mei client device
+ * @data: data to store
+ */
+void mei_cldev_set_drvdata(struct mei_cl_device *cldev, void *data)
+{
+	dev_set_drvdata(&cldev->dev, data);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_set_drvdata);
+
+/**
+ * mei_cldev_uuid - return uuid of the underlying me client
+ *
+ * @cldev: mei client device
+ *
+ * Return: me client uuid
+ */
+const uuid_le *mei_cldev_uuid(const struct mei_cl_device *cldev)
+{
+	return mei_me_cl_uuid(cldev->me_cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_uuid);
+
+/**
+ * mei_cldev_ver - return protocol version of the underlying me client
+ *
+ * @cldev: mei client device
+ *
+ * Return: me client protocol version
+ */
+u8 mei_cldev_ver(const struct mei_cl_device *cldev)
+{
+	return mei_me_cl_ver(cldev->me_cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_ver);
+
+/**
+ * mei_cldev_enabled - check whether the device is enabled
+ *
+ * @cldev: mei client device
+ *
+ * Return: true if me client is initialized and connected
+ */
+bool mei_cldev_enabled(struct mei_cl_device *cldev)
+{
+	return cldev->cl && mei_cl_is_connected(cldev->cl);
+}
+EXPORT_SYMBOL_GPL(mei_cldev_enabled);
+
+/**
+ * mei_cldev_enable - enable me client device
+ *     create connection with me client
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success and < 0 on error
+ */
+int mei_cldev_enable(struct mei_cl_device *cldev)
+{
+	struct mei_device *bus = cldev->bus;
+	struct mei_cl *cl;
+	int ret;
 
-	mutex_lock(&dev->device_lock);
+	cl = cldev->cl;
 
-	rets = mei_cl_write(cl, cb, blocking);
+	if (!cl) {
+		mutex_lock(&bus->device_lock);
+		cl = mei_cl_alloc_linked(bus, MEI_HOST_CLIENT_ID_ANY);
+		mutex_unlock(&bus->device_lock);
+		if (IS_ERR(cl))
+			return PTR_ERR(cl);
+		/* update pointers */
+		cldev->cl = cl;
+		cl->cldev = cldev;
+	}
+
+	mutex_lock(&bus->device_lock);
+	if (mei_cl_is_connected(cl)) {
+		ret = 0;
+		goto out;
+	}
 
-	mutex_unlock(&dev->device_lock);
-	if (rets < 0)
-		mei_io_cb_free(cb);
+	if (!mei_me_cl_is_active(cldev->me_cl)) {
+		dev_err(&cldev->dev, "me client is not active\n");
+		ret = -ENOTTY;
+		goto out;
+	}
 
-	return rets;
+	ret = mei_cl_connect(cl, cldev->me_cl, NULL);
+	if (ret < 0)
+		dev_err(&cldev->dev, "cannot connect\n");
+
+out:
+	mutex_unlock(&bus->device_lock);
+
+	return ret;
 }
+EXPORT_SYMBOL_GPL(mei_cldev_enable);
 
-int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
+/**
+ * mei_cldev_disable - disable me client device
+ *     disconnect form the me client
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success and < 0 on error
+ */
+int mei_cldev_disable(struct mei_cl_device *cldev)
 {
-	struct mei_device *dev;
-	struct mei_cl_cb *cb;
-	size_t r_length;
+	struct mei_device *bus;
+	struct mei_cl *cl;
 	int err;
 
-	if (WARN_ON(!cl || !cl->dev))
+	if (!cldev || !cldev->cl)
 		return -ENODEV;
 
-	dev = cl->dev;
+	cl = cldev->cl;
 
-	mutex_lock(&dev->device_lock);
+	bus = cldev->bus;
 
-	if (!cl->read_cb) {
-		err = mei_cl_read_start(cl, length);
-		if (err < 0) {
-			mutex_unlock(&dev->device_lock);
-			return err;
-		}
+	cldev->event_cb = NULL;
+
+	mutex_lock(&bus->device_lock);
+
+	if (!mei_cl_is_connected(cl)) {
+		dev_err(bus->dev, "Already disconnected");
+		err = 0;
+		goto out;
 	}
 
-	if (cl->reading_state != MEI_READ_COMPLETE &&
-	    !waitqueue_active(&cl->rx_wait)) {
+	err = mei_cl_disconnect(cl);
+	if (err < 0)
+		dev_err(bus->dev, "Could not disconnect from the ME client");
 
-		mutex_unlock(&dev->device_lock);
+out:
+	/* Flush queues and remove any pending read */
+	mei_cl_flush_queues(cl, NULL);
+	mei_cl_unlink(cl);
 
-		if (wait_event_interruptible(cl->rx_wait,
-				cl->reading_state == MEI_READ_COMPLETE  ||
-				mei_cl_is_transitioning(cl))) {
+	kfree(cl);
+	cldev->cl = NULL;
 
-			if (signal_pending(current))
-				return -EINTR;
-			return -ERESTARTSYS;
+	mutex_unlock(&bus->device_lock);
+	return err;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_disable);
+
+/**
+ * mei_cl_device_find - find matching entry in the driver id table
+ *
+ * @cldev: me client device
+ * @cldrv: me client driver
+ *
+ * Return: id on success; NULL if no id is matching
+ */
+static const
+struct mei_cl_device_id *mei_cl_device_find(struct mei_cl_device *cldev,
+					    struct mei_cl_driver *cldrv)
+{
+	const struct mei_cl_device_id *id;
+	const uuid_le *uuid;
+	u8 version;
+	bool match;
+
+	uuid = mei_me_cl_uuid(cldev->me_cl);
+	version = mei_me_cl_ver(cldev->me_cl);
+
+	id = cldrv->id_table;
+	while (uuid_le_cmp(NULL_UUID_LE, id->uuid)) {
+		if (!uuid_le_cmp(*uuid, id->uuid)) {
+			match = true;
+
+			if (cldev->name[0])
+				if (strncmp(cldev->name, id->name,
+					    sizeof(id->name)))
+					match = false;
+
+			if (id->version != MEI_CL_VERSION_ANY)
+				if (id->version != version)
+					match = false;
+			if (match)
+				return id;
 		}
 
-		mutex_lock(&dev->device_lock);
+		id++;
 	}
 
-	cb = cl->read_cb;
+	return NULL;
+}
 
-	if (cl->reading_state != MEI_READ_COMPLETE) {
-		r_length = 0;
-		goto out;
-	}
+/**
+ * mei_cl_device_match  - device match function
+ *
+ * @dev: device
+ * @drv: driver
+ *
+ * Return:  1 if matching device was found 0 otherwise
+ */
+static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	struct mei_cl_driver *cldrv = to_mei_cl_driver(drv);
+	const struct mei_cl_device_id *found_id;
 
-	r_length = min_t(size_t, length, cb->buf_idx);
+	if (!cldev)
+		return 0;
 
-	memcpy(buf, cb->response_buffer.data, r_length);
+	if (!cldev->do_match)
+		return 0;
 
-	mei_io_cb_free(cb);
-	cl->reading_state = MEI_IDLE;
-	cl->read_cb = NULL;
+	if (!cldrv || !cldrv->id_table)
+		return 0;
 
-out:
-	mutex_unlock(&dev->device_lock);
+	found_id = mei_cl_device_find(cldev, cldrv);
+	if (found_id)
+		return 1;
 
-	return r_length;
+	return 0;
 }
 
-inline int __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length)
+/**
+ * mei_cl_device_probe - bus probe function
+ *
+ * @dev: device
+ *
+ * Return:  0 on success; < 0 otherwise
+ */
+static int mei_cl_device_probe(struct device *dev)
 {
-	return ___mei_cl_send(cl, buf, length, 0);
-}
+	struct mei_cl_device *cldev;
+	struct mei_cl_driver *cldrv;
+	const struct mei_cl_device_id *id;
 
-inline int __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length)
-{
-	return ___mei_cl_send(cl, buf, length, 1);
-}
+	cldev = to_mei_cl_device(dev);
+	cldrv = to_mei_cl_driver(dev->driver);
 
-int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
-{
-	struct mei_cl *cl = device->cl;
+	if (!cldev)
+		return 0;
 
-	if (cl == NULL)
+	if (!cldrv || !cldrv->probe)
 		return -ENODEV;
 
-	if (device->ops && device->ops->send)
-		return device->ops->send(device, buf, length);
+	id = mei_cl_device_find(cldev, cldrv);
+	if (!id)
+		return -ENODEV;
 
-	return __mei_cl_send(cl, buf, length);
+	__module_get(THIS_MODULE);
+
+	return cldrv->probe(cldev, id);
 }
-EXPORT_SYMBOL_GPL(mei_cl_send);
 
-int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length)
+/**
+ * mei_cl_device_remove - remove device from the bus
+ *
+ * @dev: device
+ *
+ * Return:  0 on success; < 0 otherwise
+ */
+static int mei_cl_device_remove(struct device *dev)
 {
-	struct mei_cl *cl =  device->cl;
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	struct mei_cl_driver *cldrv;
+	int ret = 0;
 
-	if (cl == NULL)
-		return -ENODEV;
+	if (!cldev || !dev->driver)
+		return 0;
 
-	if (device->ops && device->ops->recv)
-		return device->ops->recv(device, buf, length);
+	if (cldev->event_cb) {
+		cldev->event_cb = NULL;
+		cancel_work_sync(&cldev->event_work);
+	}
 
-	return __mei_cl_recv(cl, buf, length);
+	cldrv = to_mei_cl_driver(dev->driver);
+	if (cldrv->remove)
+		ret = cldrv->remove(cldev);
+
+	module_put(THIS_MODULE);
+	dev->driver = NULL;
+	return ret;
+
+}
+
+static ssize_t name_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	size_t len;
+
+	len = snprintf(buf, PAGE_SIZE, "%s", cldev->name);
+
+	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 }
-EXPORT_SYMBOL_GPL(mei_cl_recv);
+static DEVICE_ATTR_RO(name);
 
-static void mei_bus_event_work(struct work_struct *work)
+static ssize_t uuid_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
 {
-	struct mei_cl_device *device;
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+	size_t len;
 
-	device = container_of(work, struct mei_cl_device, event_work);
+	len = snprintf(buf, PAGE_SIZE, "%pUl", uuid);
 
-	if (device->event_cb)
-		device->event_cb(device, device->events, device->event_context);
+	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+}
+static DEVICE_ATTR_RO(uuid);
 
-	device->events = 0;
+static ssize_t version_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	u8 version = mei_me_cl_ver(cldev->me_cl);
+	size_t len;
 
-	/* Prepare for the next read */
-	mei_cl_read_start(device->cl, 0);
+	len = snprintf(buf, PAGE_SIZE, "%02X", version);
+
+	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 }
+static DEVICE_ATTR_RO(version);
 
-int mei_cl_register_event_cb(struct mei_cl_device *device,
-			  mei_cl_event_cb_t event_cb, void *context)
+static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
 {
-	if (device->event_cb)
-		return -EALREADY;
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+	size_t len;
+
+	len = snprintf(buf, PAGE_SIZE, "mei:%s:%pUl:", cldev->name, uuid);
+	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+}
+static DEVICE_ATTR_RO(modalias);
+
+static struct attribute *mei_cldev_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_uuid.attr,
+	&dev_attr_version.attr,
+	&dev_attr_modalias.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(mei_cldev);
 
-	device->events = 0;
-	device->event_cb = event_cb;
-	device->event_context = context;
-	INIT_WORK(&device->event_work, mei_bus_event_work);
+/**
+ * mei_cl_device_uevent - me client bus uevent handler
+ *
+ * @dev: device
+ * @env: uevent kobject
+ *
+ * Return: 0 on success -ENOMEM on when add_uevent_var fails
+ */
+static int mei_cl_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(cldev->me_cl);
+	u8 version = mei_me_cl_ver(cldev->me_cl);
 
-	mei_cl_read_start(device->cl, 0);
+	if (add_uevent_var(env, "MEI_CL_VERSION=%d", version))
+		return -ENOMEM;
+
+	if (add_uevent_var(env, "MEI_CL_UUID=%pUl", uuid))
+		return -ENOMEM;
+
+	if (add_uevent_var(env, "MEI_CL_NAME=%s", cldev->name))
+		return -ENOMEM;
+
+	if (add_uevent_var(env, "MODALIAS=mei:%s:%pUl:%02X:",
+			   cldev->name, uuid, version))
+		return -ENOMEM;
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(mei_cl_register_event_cb);
 
-void *mei_cl_get_drvdata(const struct mei_cl_device *device)
+static struct bus_type mei_cl_bus_type = {
+	.name		= "mei",
+	.dev_groups	= mei_cldev_groups,
+	.match		= mei_cl_device_match,
+	.probe		= mei_cl_device_probe,
+	.remove		= mei_cl_device_remove,
+	.uevent		= mei_cl_device_uevent,
+};
+
+static struct mei_device *mei_dev_bus_get(struct mei_device *bus)
 {
-	return dev_get_drvdata(&device->dev);
+	if (bus)
+		get_device(bus->dev);
+
+	return bus;
 }
-EXPORT_SYMBOL_GPL(mei_cl_get_drvdata);
 
-void mei_cl_set_drvdata(struct mei_cl_device *device, void *data)
+static void mei_dev_bus_put(struct mei_device *bus)
 {
-	dev_set_drvdata(&device->dev, data);
+	if (bus)
+		put_device(bus->dev);
 }
-EXPORT_SYMBOL_GPL(mei_cl_set_drvdata);
 
-int mei_cl_enable_device(struct mei_cl_device *device)
+static void mei_cl_bus_dev_release(struct device *dev)
 {
-	int err;
-	struct mei_device *dev;
-	struct mei_cl *cl = device->cl;
+	struct mei_cl_device *cldev = to_mei_cl_device(dev);
 
-	if (cl == NULL)
-		return -ENODEV;
+	if (!cldev)
+		return;
 
-	dev = cl->dev;
+	mei_me_cl_put(cldev->me_cl);
+	mei_dev_bus_put(cldev->bus);
+	kfree(cldev);
+}
 
-	mutex_lock(&dev->device_lock);
+static struct device_type mei_cl_device_type = {
+	.release	= mei_cl_bus_dev_release,
+};
 
-	cl->state = MEI_FILE_CONNECTING;
+/**
+ * mei_cl_bus_set_name - set device name for me client device
+ *
+ * @cldev: me client device
+ */
+static inline void mei_cl_bus_set_name(struct mei_cl_device *cldev)
+{
+	dev_set_name(&cldev->dev, "mei:%s:%pUl:%02X",
+		     cldev->name,
+		     mei_me_cl_uuid(cldev->me_cl),
+		     mei_me_cl_ver(cldev->me_cl));
+}
+
+/**
+ * mei_cl_bus_dev_alloc - initialize and allocate mei client device
+ *
+ * @bus: mei device
+ * @me_cl: me client
+ *
+ * Return: allocated device structur or NULL on allocation failure
+ */
+static struct mei_cl_device *mei_cl_bus_dev_alloc(struct mei_device *bus,
+						  struct mei_me_client *me_cl)
+{
+	struct mei_cl_device *cldev;
 
-	err = mei_cl_connect(cl, NULL);
-	if (err < 0) {
-		mutex_unlock(&dev->device_lock);
-		dev_err(&dev->pdev->dev, "Could not connect to the ME client");
+	cldev = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL);
+	if (!cldev)
+		return NULL;
 
-		return err;
-	}
+	device_initialize(&cldev->dev);
+	cldev->dev.parent = bus->dev;
+	cldev->dev.bus    = &mei_cl_bus_type;
+	cldev->dev.type   = &mei_cl_device_type;
+	cldev->bus        = mei_dev_bus_get(bus);
+	cldev->me_cl      = mei_me_cl_get(me_cl);
+	mei_cl_bus_set_name(cldev);
+	cldev->is_added   = 0;
+	INIT_LIST_HEAD(&cldev->bus_list);
+
+	return cldev;
+}
+
+/**
+ * mei_cl_dev_setup - setup me client device
+ *    run fix up routines and set the device name
+ *
+ * @bus: mei device
+ * @cldev: me client device
+ *
+ * Return: true if the device is eligible for enumeration
+ */
+static bool mei_cl_bus_dev_setup(struct mei_device *bus,
+				 struct mei_cl_device *cldev)
+{
+	cldev->do_match = 1;
+	mei_cl_bus_dev_fixup(cldev);
+
+	/* the device name can change during fix up */
+	if (cldev->do_match)
+		mei_cl_bus_set_name(cldev);
+
+	return cldev->do_match == 1;
+}
+
+/**
+ * mei_cl_bus_dev_add - add me client devices
+ *
+ * @cldev: me client device
+ *
+ * Return: 0 on success; < 0 on failre
+ */
+static int mei_cl_bus_dev_add(struct mei_cl_device *cldev)
+{
+	int ret;
+
+	dev_dbg(cldev->bus->dev, "adding %pUL:%02X\n",
+		mei_me_cl_uuid(cldev->me_cl),
+		mei_me_cl_ver(cldev->me_cl));
+	ret = device_add(&cldev->dev);
+	if (!ret)
+		cldev->is_added = 1;
+
+	return ret;
+}
+
+/**
+ * mei_cl_bus_dev_stop - stop the driver
+ *
+ * @cldev: me client device
+ */
+static void mei_cl_bus_dev_stop(struct mei_cl_device *cldev)
+{
+	if (cldev->is_added)
+		device_release_driver(&cldev->dev);
+}
+
+/**
+ * mei_cl_bus_dev_destroy - destroy me client devices object
+ *
+ * @cldev: me client device
+ *
+ * Locking: called under "dev->cl_bus_lock" lock
+ */
+static void mei_cl_bus_dev_destroy(struct mei_cl_device *cldev)
+{
+
+	WARN_ON(!mutex_is_locked(&cldev->bus->cl_bus_lock));
 
-	mutex_unlock(&dev->device_lock);
+	if (!cldev->is_added)
+		return;
 
-	if (device->event_cb && !cl->read_cb)
-		mei_cl_read_start(device->cl, 0);
+	device_del(&cldev->dev);
 
-	if (!device->ops || !device->ops->enable)
-		return 0;
+	list_del_init(&cldev->bus_list);
 
-	return device->ops->enable(device);
+	cldev->is_added = 0;
+	put_device(&cldev->dev);
 }
-EXPORT_SYMBOL_GPL(mei_cl_enable_device);
 
-int mei_cl_disable_device(struct mei_cl_device *device)
+/**
+ * mei_cl_bus_remove_device - remove a devices form the bus
+ *
+ * @cldev: me client device
+ */
+static void mei_cl_bus_remove_device(struct mei_cl_device *cldev)
 {
-	int err;
-	struct mei_device *dev;
-	struct mei_cl *cl = device->cl;
+	mei_cl_bus_dev_stop(cldev);
+	mei_cl_bus_dev_destroy(cldev);
+}
 
-	if (cl == NULL)
-		return -ENODEV;
+/**
+ * mei_cl_bus_remove_devices - remove all devices form the bus
+ *
+ * @bus: mei device
+ */
+void mei_cl_bus_remove_devices(struct mei_device *bus)
+{
+	struct mei_cl_device *cldev, *next;
 
-	dev = cl->dev;
+	mutex_lock(&bus->cl_bus_lock);
+	list_for_each_entry_safe(cldev, next, &bus->device_list, bus_list)
+		mei_cl_bus_remove_device(cldev);
+	mutex_unlock(&bus->cl_bus_lock);
+}
 
-	mutex_lock(&dev->device_lock);
 
-	if (cl->state != MEI_FILE_CONNECTED) {
-		mutex_unlock(&dev->device_lock);
-		dev_err(&dev->pdev->dev, "Already disconnected");
+/**
+ * mei_cl_bus_dev_init - allocate and initializes an mei client devices
+ *     based on me client
+ *
+ * @bus: mei device
+ * @me_cl: me client
+ *
+ * Locking: called under "dev->cl_bus_lock" lock
+ */
+static void mei_cl_bus_dev_init(struct mei_device *bus,
+				struct mei_me_client *me_cl)
+{
+	struct mei_cl_device *cldev;
 
-		return 0;
-	}
+	WARN_ON(!mutex_is_locked(&bus->cl_bus_lock));
 
-	cl->state = MEI_FILE_DISCONNECTING;
+	dev_dbg(bus->dev, "initializing %pUl", mei_me_cl_uuid(me_cl));
 
-	err = mei_cl_disconnect(cl);
-	if (err < 0) {
-		mutex_unlock(&dev->device_lock);
-		dev_err(&dev->pdev->dev,
-			"Could not disconnect from the ME client");
+	if (me_cl->bus_added)
+		return;
 
-		return err;
-	}
+	cldev = mei_cl_bus_dev_alloc(bus, me_cl);
+	if (!cldev)
+		return;
 
-	/* Flush queues and remove any pending read */
-	mei_cl_flush_queues(cl);
+	me_cl->bus_added = true;
+	list_add_tail(&cldev->bus_list, &bus->device_list);
 
-	if (cl->read_cb) {
-		struct mei_cl_cb *cb = NULL;
+}
 
-		cb = mei_cl_find_read_cb(cl);
-		/* Remove entry from read list */
-		if (cb)
-			list_del(&cb->list);
-
-		cb = cl->read_cb;
-		cl->read_cb = NULL;
-
-		if (cb) {
-			mei_io_cb_free(cb);
-			cb = NULL;
-		}
-	}
+/**
+ * mei_cl_bus_rescan - scan me clients list and add create
+ *    devices for eligible clients
+ *
+ * @bus: mei device
+ */
+void mei_cl_bus_rescan(struct mei_device *bus)
+{
+	struct mei_cl_device *cldev, *n;
+	struct mei_me_client *me_cl;
 
-	device->event_cb = NULL;
+	mutex_lock(&bus->cl_bus_lock);
 
-	mutex_unlock(&dev->device_lock);
+	down_read(&bus->me_clients_rwsem);
+	list_for_each_entry(me_cl, &bus->me_clients, list)
+		mei_cl_bus_dev_init(bus, me_cl);
+	up_read(&bus->me_clients_rwsem);
 
-	if (!device->ops || !device->ops->disable)
-		return 0;
+	list_for_each_entry_safe(cldev, n, &bus->device_list, bus_list) {
+
+		if (!mei_me_cl_is_active(cldev->me_cl)) {
+			mei_cl_bus_remove_device(cldev);
+			continue;
+		}
+
+		if (cldev->is_added)
+			continue;
+
+		if (mei_cl_bus_dev_setup(bus, cldev))
+			mei_cl_bus_dev_add(cldev);
+		else {
+			list_del_init(&cldev->bus_list);
+			put_device(&cldev->dev);
+		}
+	}
+	mutex_unlock(&bus->cl_bus_lock);
 
-	return device->ops->disable(device);
+	dev_dbg(bus->dev, "rescan end");
 }
-EXPORT_SYMBOL_GPL(mei_cl_disable_device);
 
-void mei_cl_bus_rx_event(struct mei_cl *cl)
+int __mei_cldev_driver_register(struct mei_cl_driver *cldrv,
+				struct module *owner)
 {
-	struct mei_cl_device *device = cl->device;
+	int err;
 
-	if (!device || !device->event_cb)
-		return;
+	cldrv->driver.name = cldrv->name;
+	cldrv->driver.owner = owner;
+	cldrv->driver.bus = &mei_cl_bus_type;
 
-	set_bit(MEI_CL_EVENT_RX, &device->events);
+	err = driver_register(&cldrv->driver);
+	if (err)
+		return err;
+
+	pr_debug("mei: driver [%s] registered\n", cldrv->driver.name);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__mei_cldev_driver_register);
+
+void mei_cldev_driver_unregister(struct mei_cl_driver *cldrv)
+{
+	driver_unregister(&cldrv->driver);
 
-	schedule_work(&device->event_work);
+	pr_debug("mei: driver [%s] unregistered\n", cldrv->driver.name);
 }
+EXPORT_SYMBOL_GPL(mei_cldev_driver_unregister);
+
 
 int __init mei_cl_bus_init(void)
 {