diff options
authorYifeng Li <>2019-04-02 17:14:10 +0200
committerGreg Kroah-Hartman <>2019-05-25 18:22:31 +0200
commit64d314bd8cc887db7ff9822e38226b08ffc49715 (patch)
parente5c6d75b0f03958239c3d223472d00d54a6ea96a (diff)
fbdev: sm712fb: fix memory frequency by avoiding a switch/case fallthrough
commit 9dc20113988b9a75ea6b3abd68dc45e2d73ccdab upstream. A fallthrough in switch/case was introduced in f627caf55b8e ("fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting"), due to my copy-paste error, which would cause the memory clock frequency for SM720 to be programmed to SM712. Since it only reprograms the clock to a different frequency, it's only a benign issue without visible side-effect, so it also evaded Sudip Mukherjee's code review and regression tests. scripts/ also failed to discover the issue, possibly due to nested switch statements. This issue was found by Stephen Rothwell by building linux-next with -Wimplicit-fallthrough. Reported-by: Stephen Rothwell <> Fixes: f627caf55b8e ("fbdev: sm712fb: fix crashes and garbled display during DPMS modesetting") Signed-off-by: Yifeng Li <> Cc: Sudip Mukherjee <> Cc: "Gustavo A. R. Silva" <> Cc: Kees Cook <> Signed-off-by: Bartlomiej Zolnierkiewicz <> Signed-off-by: Greg Kroah-Hartman <>
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/video/fbdev/sm712fb.c b/drivers/video/fbdev/sm712fb.c
index 1e2503b52c6f..f1dcc6766d1e 100644
--- a/drivers/video/fbdev/sm712fb.c
+++ b/drivers/video/fbdev/sm712fb.c
@@ -898,6 +898,7 @@ static int smtc_blank(int blank_mode, struct fb_info *info)
case 0x712:
smtc_seqw(0x6a, 0x16);
smtc_seqw(0x6b, 0x02);
+ break;
case 0x720:
smtc_seqw(0x6a, 0x0d);
smtc_seqw(0x6b, 0x02);