Re: [PATCH] watchdog: sc1200: Mark expected switch fall-through

[Guenter Roeck]

On 2/14/19 12:20 PM, Gustavo A. R. Silva wrote:

In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.

This patch fixes the following warning:

drivers/watchdog/sc1200wdt.c: In function ‘sc1200wdt_ioctl’:
drivers/watchdog/sc1200wdt.c:241:3: warning: this statement may fall through 
[-Wimplicit-fallthrough=]
    sc1200wdt_write_data(WDTO, timeout);
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/watchdog/sc1200wdt.c:244:2: note: here
   case WDIOC_GETTIMEOUT:
   ^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

Notice that, in this particular case, the code comment is modified
in accordance with what GCC is expecting to find.

This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gust...@embeddedor.com>

Reviewed-by: Guenter Roeck <li...@roeck-us.net>

---
  drivers/watchdog/sc1200wdt.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/watchdog/sc1200wdt.c b/drivers/watchdog/sc1200wdt.c
index 8e4e2fc13f87..e035a4d4b299 100644
--- a/drivers/watchdog/sc1200wdt.c
+++ b/drivers/watchdog/sc1200wdt.c
@@ -239,7 +239,7 @@ static long sc1200wdt_ioctl(struct file *file, unsigned int 
cmd,
                        return -EINVAL;
                timeout = new_timeout;
                sc1200wdt_write_data(WDTO, timeout);
-               /* fall through and return the new timeout */
+               /* fall through - and return the new timeout */

case WDIOC_GETTIMEOUT:

                return put_user(timeout * 60, p);