usb: gadget: FunctionFS: Return -ENOENT instead of -ENODEV when device not found.

Syscall mount returns -ENODEV error if requested FS type
has not been found. Returning the same error from FFS mount
callback makes value returned to userspace misleading.

Other file systems returns -ENOENT if requested device
has not been found. Adjust FFS to this convention to make
error codes meaningfull.
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/f_fs.c

@@ -2899,12 +2899,12 @@ static void *ffs_acquire_dev(const char *dev_name)
 
 	ffs_dev = _ffs_find_dev(dev_name);
 	if (!ffs_dev)
-		ffs_dev = ERR_PTR(-ENODEV);
+		ffs_dev = ERR_PTR(-ENOENT);
 	else if (ffs_dev->mounted)
 		ffs_dev = ERR_PTR(-EBUSY);
 	else if (ffs_dev->ffs_acquire_dev_callback &&
 	    ffs_dev->ffs_acquire_dev_callback(ffs_dev))
-		ffs_dev = ERR_PTR(-ENODEV);
+		ffs_dev = ERR_PTR(-ENOENT);
 	else
 		ffs_dev->mounted = true;
 

drivers/usb/gadget/g_ffs.c

@@ -276,7 +276,7 @@ module_exit(gfs_exit);
 static void *functionfs_acquire_dev(struct ffs_dev *dev)
 {
 	if (!try_module_get(THIS_MODULE))
-		return ERR_PTR(-ENODEV);
+		return ERR_PTR(-ENOENT);
 	
 	return 0;
 }