mei: add mei_cl_alloc_linked function

Add convenient wrapper mei_cl_alloc_linked
to simplify error handling

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

4 files changed, 61 insertions, 36 deletions

diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index 57461016f1ff..e263c0713a6d 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -547,11 +547,11 @@ struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl)
  * mei_cl_link - allocate host id in the host map
  *
  * @cl: host client
- * @id: fixed host id or -1 for generic one
+ * @id: fixed host id or MEI_HOST_CLIENT_ID_ANY (-1) for generic one
  *
  * Return: 0 on success
  *      -EINVAL on incorrect values
- *      -ENONET if client not found
+ *      -EMFILE if open count exceeded.
  */
 int mei_cl_link(struct mei_cl *cl, int id)
 {
@@ -870,6 +870,37 @@ out:
 }
 
 /**
+ * mei_cl_alloc_linked - allocate and link host client
+ *
+ * @dev: the device structure
+ * @id: fixed host id or MEI_HOST_CLIENT_ID_ANY (-1) for generic one
+ *
+ * Return: cl on success ERR_PTR on failure
+ */
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev, int id)
+{
+        struct mei_cl *cl;
+        int ret;
+
+        cl = mei_cl_allocate(dev);
+        if (!cl) {
+                ret = -ENOMEM;
+                goto err;
+        }
+
+        ret = mei_cl_link(cl, id);
+        if (ret)
+                goto err;
+
+        return cl;
+err:
+        kfree(cl);
+        return ERR_PTR(ret);
+}
+
+
+
+/**
  * mei_cl_flow_ctrl_creds - checks flow_control credits for cl.
  *
  * @cl: private data of the file object
diff --git a/drivers/misc/mei/client.h b/drivers/misc/mei/client.h
index f7d0285b5f57..c3d0e200a642 100644
--- a/drivers/misc/mei/client.h
+++ b/drivers/misc/mei/client.h
@@ -75,6 +75,8 @@ void mei_cl_init(struct mei_cl *cl, struct mei_device *dev);
 int mei_cl_link(struct mei_cl *cl, int id);
 int mei_cl_unlink(struct mei_cl *cl);
 
+struct mei_cl *mei_cl_alloc_linked(struct mei_device *dev, int id);
+
 int mei_cl_flush_queues(struct mei_cl *cl);
 struct mei_cl_cb *mei_cl_find_read_cb(struct mei_cl *cl);
 
diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index 369de0a070f1..10fc3a6a1574 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -59,24 +59,18 @@ static int mei_open(struct inode *inode, struct file *file)
 
         mutex_lock(&dev->device_lock);
 
-        cl = NULL;
-
-        err = -ENODEV;
         if (dev->dev_state != MEI_DEV_ENABLED) {
                 dev_dbg(dev->dev, "dev_state != MEI_ENABLED  dev_state = %s\n",
                     mei_dev_state_str(dev->dev_state));
+                err = -ENODEV;
                 goto err_unlock;
         }
 
-        err = -ENOMEM;
-        cl = mei_cl_allocate(dev);
-        if (!cl)
-                goto err_unlock;
-
-        /* open_handle_count check is handled in the mei_cl_link */
-        err = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
-        if (err)
+        cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+        if (IS_ERR(cl)) {
+                err = PTR_ERR(cl);
                 goto err_unlock;
+        }
 
         file->private_data = cl;
 
@@ -86,7 +80,6 @@ static int mei_open(struct inode *inode, struct file *file)
 
 err_unlock:
         mutex_unlock(&dev->device_lock);
-        kfree(cl);
         return err;
 }
 
diff --git a/drivers/misc/mei/nfc.c b/drivers/misc/mei/nfc.c
index bb61a119b8bb..c3bcb63686d7 100644
--- a/drivers/misc/mei/nfc.c
+++ b/drivers/misc/mei/nfc.c
@@ -482,8 +482,8 @@ err:
 int mei_nfc_host_init(struct mei_device *dev)
 {
         struct mei_nfc_dev *ndev;
-        struct mei_cl *cl_info, *cl = NULL;
-        struct mei_me_client *me_cl;
+        struct mei_cl *cl_info, *cl;
+        struct mei_me_client *me_cl = NULL;
         int ret;
 
 
@@ -500,17 +500,6 @@ int mei_nfc_host_init(struct mei_device *dev)
                 goto err;
         }
 
-        ndev->cl_info = mei_cl_allocate(dev);
-        ndev->cl = mei_cl_allocate(dev);
-
-        cl = ndev->cl;
-        cl_info = ndev->cl_info;
-
-        if (!cl || !cl_info) {
-                ret = -ENOMEM;
-                goto err;
-        }
-
         /* check for valid client id */
         me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_info_guid);
         if (!me_cl) {
@@ -519,17 +508,21 @@ int mei_nfc_host_init(struct mei_device *dev)
                 goto err;
         }
 
+        cl_info = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+        if (IS_ERR(cl_info)) {
+                ret = PTR_ERR(cl_info);
+                goto err;
+        }
+
         cl_info->me_client_id = me_cl->client_id;
         cl_info->cl_uuid = me_cl->props.protocol_name;
         mei_me_cl_put(me_cl);
-
-        ret = mei_cl_link(cl_info, MEI_HOST_CLIENT_ID_ANY);
-        if (ret)
-                goto err;
-
+        me_cl = NULL;
 
         list_add_tail(&cl_info->device_link, &dev->device_list);
 
+        ndev->cl_info = cl_info;
+
         /* check for valid client id */
         me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_guid);
         if (!me_cl) {
@@ -538,16 +531,21 @@ int mei_nfc_host_init(struct mei_device *dev)
                 goto err;
         }
 
+        cl = mei_cl_alloc_linked(dev, MEI_HOST_CLIENT_ID_ANY);
+        if (IS_ERR(cl)) {
+                ret = PTR_ERR(cl);
+                goto err;
+        }
+
         cl->me_client_id = me_cl->client_id;
         cl->cl_uuid = me_cl->props.protocol_name;
         mei_me_cl_put(me_cl);
-
-        ret = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
-        if (ret)
-                goto err;
+        me_cl = NULL;
 
         list_add_tail(&cl->device_link, &dev->device_list);
 
+        ndev->cl = cl;
+
         ndev->req_id = 1;
 
         INIT_WORK(&ndev->init_work, mei_nfc_init);
@@ -557,6 +555,7 @@ int mei_nfc_host_init(struct mei_device *dev)
         return 0;
 
 err:
+        mei_me_cl_put(me_cl);
         mei_nfc_free(ndev);
 
         return ret;