mei: bus: add me client device list infrastructure

Instead of holding the list of host clients (me_cl)
we want to keep the list me client devices (mei_cl_device)
This way we can create host to me client connection only when needed.
Add list head to mei_cl_device and cl_bus_lock
Add bus_added flag to the me client (mei_me_client) to track if
the appropriate mei_cl_device was already created and is_added
flag to mei_cl_device to track if it was already added to the device
list across the bus rescans

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
index 963731e..34b14dd 100644
--- a/drivers/misc/mei/bus.c
+++ b/drivers/misc/mei/bus.c
@@ -657,6 +657,7 @@
 	cldev->dev.bus = &mei_cl_bus_type;
 	cldev->dev.type = &mei_cl_device_type;
 	cldev->bus      = mei_dev_bus_get(bus);
+	INIT_LIST_HEAD(&cldev->bus_list);
 
 	strlcpy(cldev->name, name, sizeof(cldev->name));
 
diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
index 00c3865..15000e9 100644
--- a/drivers/misc/mei/init.c
+++ b/drivers/misc/mei/init.c
@@ -390,6 +390,7 @@
 	INIT_LIST_HEAD(&dev->me_clients);
 	mutex_init(&dev->device_lock);
 	init_rwsem(&dev->me_clients_rwsem);
+	mutex_init(&dev->cl_bus_lock);
 	init_waitqueue_head(&dev->wait_hw_ready);
 	init_waitqueue_head(&dev->wait_pg);
 	init_waitqueue_head(&dev->wait_hbm_start);
diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index bc65fb4..882e6f7 100644
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -178,7 +178,7 @@
  * @client_id: me client id
  * @mei_flow_ctrl_creds: flow control credits
  * @connect_count: number connections to this client
- * @reserved: reserved
+ * @bus_added: added to bus
  */
 struct mei_me_client {
 	struct list_head list;
@@ -187,7 +187,7 @@
 	u8 client_id;
 	u8 mei_flow_ctrl_creds;
 	u8 connect_count;
-	u8 reserved;
+	u8 bus_added;
 };
 
 
@@ -447,6 +447,7 @@
  * @reset_work  : work item for the device reset
  *
  * @device_list : mei client bus list
+ * @cl_bus_lock : client bus list lock
  *
  * @dbgfs_dir   : debugfs mei root directory
  *
@@ -543,6 +544,7 @@
 
 	/* List of bus devices */
 	struct list_head device_list;
+	struct mutex cl_bus_lock;
 
 #if IS_ENABLED(CONFIG_DEBUG_FS)
 	struct dentry *dbgfs_dir;