iwlwifi: rework the iwlwifi debugfs structure

The generic part of the driver now creates all debugfs
directories. It creates a root directory directly in
the the root of the debugfs filesystem and within that
directories for each device, named after the device ID
of the devices iwlwifi is attached to.

In the cfg80211/mac80211 directory there's now a link
to the toplevel iwlwifi debugfs directory to make it
easier to find the debugfs files.

Signed-off-by: Meenakshi Venkataraman <meenakshi.venkataraman@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/dvm/debugfs.c b/drivers/net/wireless/iwlwifi/dvm/debugfs.c
index 46782f1..ce826bc 100644
--- a/drivers/net/wireless/iwlwifi/dvm/debugfs.c
+++ b/drivers/net/wireless/iwlwifi/dvm/debugfs.c
@@ -2349,24 +2349,19 @@
  * Create the debugfs files and directories
  *
  */
-int iwl_dbgfs_register(struct iwl_priv *priv, const char *name)
+int iwl_dbgfs_register(struct iwl_priv *priv, struct dentry *dbgfs_dir)
 {
-	struct dentry *phyd = priv->hw->wiphy->debugfsdir;
-	struct dentry *dir_drv, *dir_data, *dir_rf, *dir_debug;
+	struct dentry *dir_data, *dir_rf, *dir_debug;
 
-	dir_drv = debugfs_create_dir(name, phyd);
-	if (!dir_drv)
-		return -ENOMEM;
+	priv->debugfs_dir = dbgfs_dir;
 
-	priv->debugfs_dir = dir_drv;
-
-	dir_data = debugfs_create_dir("data", dir_drv);
+	dir_data = debugfs_create_dir("data", dbgfs_dir);
 	if (!dir_data)
 		goto err;
-	dir_rf = debugfs_create_dir("rf", dir_drv);
+	dir_rf = debugfs_create_dir("rf", dbgfs_dir);
 	if (!dir_rf)
 		goto err;
-	dir_debug = debugfs_create_dir("debug", dir_drv);
+	dir_debug = debugfs_create_dir("debug", dbgfs_dir);
 	if (!dir_debug)
 		goto err;
 
@@ -2412,25 +2407,30 @@
 	/* Calibrations disabled/enabled status*/
 	DEBUGFS_ADD_FILE(calib_disabled, dir_rf, S_IWUSR | S_IRUSR);
 
-	if (iwl_trans_dbgfs_register(priv->trans, dir_debug))
-		goto err;
+	/*
+	 * Create a symlink with mac80211. This is not very robust, as it does
+	 * not remove the symlink created. The implicit assumption is that
+	 * when the opmode exits, mac80211 will also exit, and will remove
+	 * this symlink as part of its cleanup.
+	 */
+	if (priv->mac80211_registered) {
+		char buf[100];
+		struct dentry *mac80211_dir, *dev_dir, *root_dir;
+
+		dev_dir = dbgfs_dir->d_parent;
+		root_dir = dev_dir->d_parent;
+		mac80211_dir = priv->hw->wiphy->debugfsdir;
+
+		snprintf(buf, 100, "../../%s/%s", root_dir->d_name.name,
+			 dev_dir->d_name.name);
+
+		if (!debugfs_create_symlink("iwlwifi", mac80211_dir, buf))
+			goto err;
+	}
+
 	return 0;
 
 err:
-	IWL_ERR(priv, "Can't create the debugfs directory\n");
-	iwl_dbgfs_unregister(priv);
+	IWL_ERR(priv, "failed to create the dvm debugfs entries\n");
 	return -ENOMEM;
 }
-
-/**
- * Remove the debugfs files and directories
- *
- */
-void iwl_dbgfs_unregister(struct iwl_priv *priv)
-{
-	if (!priv->debugfs_dir)
-		return;
-
-	debugfs_remove_recursive(priv->debugfs_dir);
-	priv->debugfs_dir = NULL;
-}