mei: nfc: clean nfc internal struct on host exit

NFC internal structure cleaning was dropped by commit

commit 48705693
Author: Tomas Winkler <tomas.winkler@intel.com>
Date:   Mon Feb 17 15:13:19 2014 +0200

    mei: Remove all bus devices from the mei_dev list when stopping the MEI

    When stopping the MEI, we should remove and potentially unregister
    all bus devices queued on the mei_dev linked list.

We allocate nfc_dev and free it across the reset
so we do not keep it in dirty state
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/bus.c

@@ -140,7 +140,7 @@ static struct device_type mei_cl_device_type = {
 	.release	= mei_cl_dev_release,
 };
 
-static struct mei_cl *mei_bus_find_mei_cl_by_uuid(struct mei_device *dev,
+struct mei_cl *mei_cl_bus_find_cl_by_uuid(struct mei_device *dev,
 						uuid_le uuid)
 {
 	struct mei_cl *cl;
@@ -160,7 +160,7 @@ struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
 	struct mei_cl *cl;
 	int status;
 
-	cl = mei_bus_find_mei_cl_by_uuid(dev, uuid);
+	cl = mei_cl_bus_find_cl_by_uuid(dev, uuid);
 	if (cl == NULL)
 		return NULL;
 

drivers/misc/mei/mei_dev.h

@@ -349,6 +349,7 @@ void mei_cl_bus_rx_event(struct mei_cl *cl);
 void mei_cl_bus_remove_devices(struct mei_device *dev);
 int mei_cl_bus_init(void);
 void mei_cl_bus_exit(void);
+struct mei_cl *mei_cl_bus_find_cl_by_uuid(struct mei_device *dev, uuid_le uuid);
 
 
 /**

drivers/misc/mei/nfc.c

@@ -117,8 +117,6 @@ struct mei_nfc_dev {
 	u16 recv_req_id;
 };
 
-static struct mei_nfc_dev nfc_dev;
-
 /* UUIDs for NFC F/W clients */
 const uuid_le mei_nfc_guid = UUID_LE(0x0bb17a78, 0x2a8e, 0x4c50,
 				     0x94, 0xd4, 0x50, 0x26,
@@ -138,6 +136,9 @@ static const uuid_le mei_nfc_info_guid = UUID_LE(0xd2de1625, 0x382d, 0x417d,
 
 static void mei_nfc_free(struct mei_nfc_dev *ndev)
 {
+	if (!ndev)
+		return;
+
 	if (ndev->cl) {
 		list_del(&ndev->cl->device_link);
 		mei_cl_unlink(ndev->cl);
@@ -150,7 +151,7 @@ static void mei_nfc_free(struct mei_nfc_dev *ndev)
 		kfree(ndev->cl_info);
 	}
 
-	memset(ndev, 0, sizeof(struct mei_nfc_dev));
+	kfree(ndev);
 }
 
 static int mei_nfc_build_bus_name(struct mei_nfc_dev *ndev)
@@ -319,9 +320,10 @@ static int mei_nfc_if_version(struct mei_nfc_dev *ndev)
 static int mei_nfc_enable(struct mei_cl_device *cldev)
 {
 	struct mei_device *dev;
-	struct mei_nfc_dev *ndev = &nfc_dev;
+	struct mei_nfc_dev *ndev;
 	int ret;
 
+	ndev = (struct mei_nfc_dev *)cldev->priv_data;
 	dev = ndev->cl->dev;
 
 	ret = mei_nfc_connect(ndev);
@@ -479,15 +481,25 @@ static void mei_nfc_init(struct work_struct *work)
 
 int mei_nfc_host_init(struct mei_device *dev)
 {
-	struct mei_nfc_dev *ndev = &nfc_dev;
+	struct mei_nfc_dev *ndev;
 	struct mei_cl *cl_info, *cl = NULL;
 	struct mei_me_client *me_cl;
 	int ret;
 
-	/* already initialized */
-	if (ndev->cl_info)
+
+	/* in case of internal reset bail out
+	 * as the device is already setup
+	 */
+	cl = mei_cl_bus_find_cl_by_uuid(dev, mei_nfc_guid);
+	if (cl)
 		return 0;
 
+	ndev = kzalloc(sizeof(struct mei_nfc_dev), GFP_KERNEL);
+	if (!ndev) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
 	ndev->cl_info = mei_cl_allocate(dev);
 	ndev->cl = mei_cl_allocate(dev);
 
@@ -550,9 +562,31 @@ int mei_nfc_host_init(struct mei_device *dev)
 
 void mei_nfc_host_exit(struct mei_device *dev)
 {
-	struct mei_nfc_dev *ndev = &nfc_dev;
+	struct mei_nfc_dev *ndev;
+	struct mei_cl *cl;
+	struct mei_cl_device *cldev;
+
+	cl = mei_cl_bus_find_cl_by_uuid(dev, mei_nfc_guid);
+	if (!cl)
+		return;
+
+	cldev = cl->device;
+	if (!cldev)
+		return;
 
-	cancel_work_sync(&ndev->init_work);
+	ndev = (struct mei_nfc_dev *)cldev->priv_data;
+	if (ndev)
+		cancel_work_sync(&ndev->init_work);
+
+	cldev->priv_data = NULL;
+
+	mutex_lock(&dev->device_lock);
+	/* Need to remove the device here
+	 * since mei_nfc_free will unlink the clients
+	 */
+	mei_cl_remove_device(cldev);
+	mei_nfc_free(ndev);
+	mutex_unlock(&dev->device_lock);
 }