linux-kernel - [PATCH v2] mei: no need to check return value of debugfs

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Date:   Tue, 11 Jun 2019 20:38:16 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     Tomas Winkler <tomas.winkler@...el.com>
Cc:     Arnd Bergmann <arnd@...db.de>, linux-kernel@...r.kernel.org
Subject: [PATCH v2] mei: no need to check return value of debugfs_create
 functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Tomas Winkler <tomas.winkler@...el.com>
Cc: Arnd Bergmann <arnd@...db.de>
Cc: linux-kernel@...r.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
v2: break the patch up properly

 drivers/misc/mei/debugfs.c | 47 +++++++++-----------------------------
 drivers/misc/mei/main.c    |  8 +------
 drivers/misc/mei/mei_dev.h |  7 ++----
 3 files changed, 14 insertions(+), 48 deletions(-)

diff --git a/drivers/misc/mei/debugfs.c b/drivers/misc/mei/debugfs.c
index 0970142bcace..df6bf8b81936 100644
--- a/drivers/misc/mei/debugfs.c
+++ b/drivers/misc/mei/debugfs.c
@@ -233,47 +233,22 @@ void mei_dbgfs_deregister(struct mei_device *dev)
  *
  * @dev: the mei device structure
  * @name: the mei device name
- *
- * Return: 0 on success, <0 on failure.
  */
-int mei_dbgfs_register(struct mei_device *dev, const char *name)
+void mei_dbgfs_register(struct mei_device *dev, const char *name)
 {
-	struct dentry *dir, *f;
+	struct dentry *dir;
 
 	dir = debugfs_create_dir(name, NULL);
-	if (!dir)
-		return -ENOMEM;
-
 	dev->dbgfs_dir = dir;
 
-	f = debugfs_create_file("meclients", S_IRUSR, dir,
-				dev, &mei_dbgfs_fops_meclients);
-	if (!f) {
-		dev_err(dev->dev, "meclients: registration failed\n");
-		goto err;
-	}
-	f = debugfs_create_file("active", S_IRUSR, dir,
-				dev, &mei_dbgfs_fops_active);
-	if (!f) {
-		dev_err(dev->dev, "active: registration failed\n");
-		goto err;
-	}
-	f = debugfs_create_file("devstate", S_IRUSR, dir,
-				dev, &mei_dbgfs_fops_devstate);
-	if (!f) {
-		dev_err(dev->dev, "devstate: registration failed\n");
-		goto err;
-	}
-	f = debugfs_create_file("allow_fixed_address", S_IRUSR | S_IWUSR, dir,
-				&dev->allow_fixed_address,
-				&mei_dbgfs_fops_allow_fa);
-	if (!f) {
-		dev_err(dev->dev, "allow_fixed_address: registration failed\n");
-		goto err;
-	}
-	return 0;
-err:
-	mei_dbgfs_deregister(dev);
-	return -ENODEV;
+	debugfs_create_file("meclients", S_IRUSR, dir, dev,
+			    &mei_dbgfs_fops_meclients);
+	debugfs_create_file("active", S_IRUSR, dir, dev,
+			    &mei_dbgfs_fops_active);
+	debugfs_create_file("devstate", S_IRUSR, dir, dev,
+			    &mei_dbgfs_fops_devstate);
+	debugfs_create_file("allow_fixed_address", S_IRUSR | S_IWUSR, dir,
+			    &dev->allow_fixed_address,
+			    &mei_dbgfs_fops_allow_fa);
 }
 
diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index ad02097d7fee..f894d1f8a53e 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -984,16 +984,10 @@ int mei_register(struct mei_device *dev, struct device *parent)
 		goto err_dev_create;
 	}
 
-	ret = mei_dbgfs_register(dev, dev_name(clsdev));
-	if (ret) {
-		dev_err(clsdev, "cannot register debugfs ret = %d\n", ret);
-		goto err_dev_dbgfs;
-	}
+	mei_dbgfs_register(dev, dev_name(clsdev));
 
 	return 0;
 
-err_dev_dbgfs:
-	device_destroy(mei_class, devno);
 err_dev_create:
 	cdev_del(&dev->cdev);
 err_dev_add:
diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index fca832fcac57..f71a023aed3c 100644
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -718,13 +718,10 @@ bool mei_hbuf_acquire(struct mei_device *dev);
 bool mei_write_is_idle(struct mei_device *dev);
 
 #if IS_ENABLED(CONFIG_DEBUG_FS)
-int mei_dbgfs_register(struct mei_device *dev, const char *name);
+void mei_dbgfs_register(struct mei_device *dev, const char *name);
 void mei_dbgfs_deregister(struct mei_device *dev);
 #else
-static inline int mei_dbgfs_register(struct mei_device *dev, const char *name)
-{
-	return 0;
-}
+static inline void mei_dbgfs_register(struct mei_device *dev, const char *name) {}
 static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
 #endif /* CONFIG_DEBUG_FS */
 
-- 
2.22.0