[PATCH v6 10/10] clocksource: timer-dm: Check prescaler value

From: Keerthy
Date: Tue Jan 02 2018 - 05:13:15 EST


From: Ladislav Michl <ladis@xxxxxxxxxxxxxx>

Invalid prescaler value is silently ignored. Fix that
by returning -EINVAL in such case. As invalid value
disabled use of the prescaler, use -1 explicitely for
that purpose.

Signed-off-by: Ladislav Michl <ladis@xxxxxxxxxxxxxx>
---
drivers/clocksource/timer-dm.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/clocksource/timer-dm.c b/drivers/clocksource/timer-dm.c
index 60db173..01a9cb0 100644
--- a/drivers/clocksource/timer-dm.c
+++ b/drivers/clocksource/timer-dm.c
@@ -672,6 +672,9 @@ int omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
if (prescaler >= 0x00 && prescaler <= 0x07) {
l |= OMAP_TIMER_CTRL_PRE;
l |= prescaler << 2;
+ } else {
+ if (prescaler != -1)
+ return -EINVAL;
}
omap_dm_timer_write_reg(timer, OMAP_TIMER_CTRL_REG, l);

--
1.9.1