base: core: WARN() about bogus permissions on device attributes

Whenever a struct device_attribute is registered
with mismatched permissions - read permission without
a show routine or write permission without store
routine - we will issue a big warning so we catch
those early enough.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 56536f4b0f6b9bfd6c3aa4aa603e43e75112de87..a7391a30cb294ab7fbc405b6f5b2496654626dc2 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -563,8 +563,15 @@ int device_create_file(struct device *dev,
                       const struct device_attribute *attr)
 {
        int error = 0;
-       if (dev)
+
+       if (dev) {
+               WARN(((attr->attr.mode & S_IWUGO) && !attr->store),
+                               "Write permission without 'store'\n");
+               WARN(((attr->attr.mode & S_IRUGO) && !attr->show),
+                               "Read permission without 'show'\n");
                error = sysfs_create_file(&dev->kobj, &attr->attr);
+       }
+
        return error;
 }