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>

3 files changed, 37 insertions, 40 deletions

diff --git a/drivers/net/wireless/iwlwifi/dvm/agn.h b/drivers/net/wireless/iwlwifi/dvm/agn.h
index 9bb16bdf6d26..12762dc40409 100644
--- a/drivers/net/wireless/iwlwifi/dvm/agn.h
+++ b/drivers/net/wireless/iwlwifi/dvm/agn.h
@@ -485,16 +485,13 @@ static inline void iwl_dvm_set_pmi(struct iwl_priv *priv, bool state)
 }
 
 #ifdef CONFIG_IWLWIFI_DEBUGFS
-int iwl_dbgfs_register(struct iwl_priv *priv, const char *name);
-void iwl_dbgfs_unregister(struct iwl_priv *priv);
+int iwl_dbgfs_register(struct iwl_priv *priv, struct dentry *dbgfs_dir);
 #else
-static inline int iwl_dbgfs_register(struct iwl_priv *priv, const char *name)
+static inline int iwl_dbgfs_register(struct iwl_priv *priv,
+				     struct dentry *dbgfs_dir)
 {
 	return 0;
 }
-static inline void iwl_dbgfs_unregister(struct iwl_priv *priv)
-{
-}
 #endif /* CONFIG_IWLWIFI_DEBUGFS */
 
 #ifdef CONFIG_IWLWIFI_DEBUG
diff --git a/drivers/net/wireless/iwlwifi/dvm/debugfs.c b/drivers/net/wireless/iwlwifi/dvm/debugfs.c
index 46782f1102ac..ce826bc5f111 100644
--- a/drivers/net/wireless/iwlwifi/dvm/debugfs.c
+++ b/drivers/net/wireless/iwlwifi/dvm/debugfs.c
@@ -2349,24 +2349,19 @@ DEBUGFS_READ_WRITE_FILE_OPS(calib_disabled);
  * 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 = dir_drv;
+	priv->debugfs_dir = dbgfs_dir;
 
-	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 @@ int iwl_dbgfs_register(struct iwl_priv *priv, const char *name)
 	/* 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;
-}
diff --git a/drivers/net/wireless/iwlwifi/dvm/main.c b/drivers/net/wireless/iwlwifi/dvm/main.c
index e8ffbe424b42..ab7b9ed00b8f 100644
--- a/drivers/net/wireless/iwlwifi/dvm/main.c
+++ b/drivers/net/wireless/iwlwifi/dvm/main.c
@@ -1222,7 +1222,8 @@ static int iwl_eeprom_init_hw_params(struct iwl_priv *priv)
 
 static struct iwl_op_mode *iwl_op_mode_dvm_start(struct iwl_trans *trans,
 						 const struct iwl_cfg *cfg,
-						 const struct iwl_fw *fw)
+						 const struct iwl_fw *fw,
+						 struct dentry *dbgfs_dir)
 {
 	struct iwl_priv *priv;
 	struct ieee80211_hw *hw;
@@ -1466,12 +1467,13 @@ static struct iwl_op_mode *iwl_op_mode_dvm_start(struct iwl_trans *trans,
 	if (iwlagn_mac_setup_register(priv, &fw->ucode_capa))
 		goto out_destroy_workqueue;
 
-	if (iwl_dbgfs_register(priv, DRV_NAME))
-		IWL_ERR(priv,
-			"failed to create debugfs files. Ignoring error\n");
+	if (iwl_dbgfs_register(priv, dbgfs_dir))
+		goto out_mac80211_unregister;
 
 	return op_mode;
 
+out_mac80211_unregister:
+	iwlagn_mac_unregister(priv);
 out_destroy_workqueue:
 	iwl_tt_exit(priv);
 	iwl_testmode_free(priv);
@@ -1496,8 +1498,6 @@ static void iwl_op_mode_dvm_stop(struct iwl_op_mode *op_mode)
 
 	IWL_DEBUG_INFO(priv, "*** UNLOAD DRIVER ***\n");
 
-	iwl_dbgfs_unregister(priv);
-
 	iwl_testmode_free(priv);
 	iwlagn_mac_unregister(priv);