mei: bus: Add bus related structures to mei_cl

We keep track of all MEI devices on the bus through a specific linked list.
We also have a mei_device instance in the mei_cl structure.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/bus.c

@@ -140,36 +140,53 @@ static struct device_type mei_cl_device_type = {
 	.release	= mei_cl_dev_release,
 };
 
-struct mei_cl_device *mei_cl_add_device(struct mei_device *mei_device,
+static struct mei_cl *mei_bus_find_mei_cl_by_uuid(struct mei_device *dev,
+						uuid_le uuid)
+{
+	struct mei_cl *cl, *next;
+
+	list_for_each_entry_safe(cl, next, &dev->device_list, device_link) {
+		if (!uuid_le_cmp(uuid, cl->device_uuid))
+			return cl;
+	}
+
+	return NULL;
+}
+struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
 				  uuid_le uuid, char *name)
 {
 	struct mei_cl_device *device;
+	struct mei_cl *cl;
 	int status;
 
+	cl = mei_bus_find_mei_cl_by_uuid(dev, uuid);
+	if (cl == NULL)
+		return NULL;
+
 	device = kzalloc(sizeof(struct mei_cl_device), GFP_KERNEL);
 	if (!device)
 		return NULL;
 
-	device->dev.parent = &mei_device->pdev->dev;
+	device->cl = cl;
+
+	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)
-		goto out_err;
+	if (status) {
+		dev_err(&dev->pdev->dev, "Failed to register MEI device\n");
+		kfree(device);
+		return NULL;
+	}
+
+	cl->device = device;
 
 	dev_dbg(&device->dev, "client %s registered\n", name);
 
 	return device;
-
-out_err:
-	dev_err(device->dev.parent, "Failed to register MEI client\n");
-
-	kfree(device);
-
-	return NULL;
 }
 EXPORT_SYMBOL_GPL(mei_cl_add_device);
 
@@ -367,9 +384,10 @@ int __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length)
 
 int mei_cl_send(struct mei_cl_device *device, u8 *buf, size_t length)
 {
-	struct mei_cl *cl = NULL;
+	struct mei_cl *cl = device->cl;
 
-	/* TODO: hook between mei_bus_client and mei_cl */
+	if (cl == NULL)
+		return -ENODEV;
 
 	if (device->ops && device->ops->send)
 		return device->ops->send(device, buf, length);
@@ -380,9 +398,10 @@ EXPORT_SYMBOL_GPL(mei_cl_send);
 
 int mei_cl_recv(struct mei_cl_device *device, u8 *buf, size_t length)
 {
-	struct mei_cl *cl = NULL;
+	struct mei_cl *cl =  device->cl;
 
-	/* TODO: hook between mei_bus_client and mei_cl */
+	if (cl == NULL)
+		return -ENODEV;
 
 	if (device->ops && device->ops->recv)
 		return device->ops->recv(device, buf, length);

drivers/misc/mei/client.c

@@ -216,6 +216,7 @@ void mei_cl_init(struct mei_cl *cl, struct mei_device *dev)
 	init_waitqueue_head(&cl->rx_wait);
 	init_waitqueue_head(&cl->tx_wait);
 	INIT_LIST_HEAD(&cl->link);
+	INIT_LIST_HEAD(&cl->device_link);
 	cl->reading_state = MEI_IDLE;
 	cl->writing_state = MEI_IDLE;
 	cl->dev = dev;

drivers/misc/mei/init.c

@@ -47,6 +47,7 @@ void mei_device_init(struct mei_device *dev)
 {
 	/* setup our list array */
 	INIT_LIST_HEAD(&dev->file_list);
+	INIT_LIST_HEAD(&dev->device_list);
 	mutex_init(&dev->device_lock);
 	init_waitqueue_head(&dev->wait_hw_ready);
 	init_waitqueue_head(&dev->wait_recvd_msg);

drivers/misc/mei/mei_dev.h

@@ -209,6 +209,11 @@ struct mei_cl {
 	enum mei_file_transaction_states writing_state;
 	int sm_state;
 	struct mei_cl_cb *read_cb;
+
+	/* MEI CL bus data */
+	struct mei_cl_device *device;
+	struct list_head device_link;
+	uuid_le device_uuid;
 };
 
 /** struct mei_hw_ops
@@ -423,6 +428,9 @@ struct mei_device {
 
 	struct work_struct init_work;
 
+	/* List of bus devices */
+	struct list_head device_list;
+
 	const struct mei_hw_ops *ops;
 	char hw[0] __aligned(sizeof(void *));
 };