1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c
index 025c60a17a4a..90dfa0df747a 100644
--- a/drivers/rtc/rtc-dev.c
+++ b/drivers/rtc/rtc-dev.c
@@ -246,6 +246,15 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,
         /* if the driver does not provide the ioctl interface
          * or if that particular ioctl was not implemented
          * (-ENOIOCTLCMD), we will try to emulate here.
+         *
+         * Drivers *SHOULD NOT* provide ioctl implementations
+         * for these requests.  Instead, provide methods to
+         * support the following code, so that the RTC's main
+         * features are accessible without using ioctls.
+         *
+         * RTC and alarm times will be in UTC, by preference,
+         * but dual-booting with MS-Windows implies RTCs must
+         * use the local wall clock time.
          */
 
         switch (cmd) {