diff options
| author | Yicheng Li <yichengli@chromium.org> | 2019-10-08 17:31:56 -0700 |
|---|---|---|
| committer | Commit Bot <commit-bot@chromium.org> | 2019-10-12 11:43:38 +0000 |
| commit | a6c2477aca71c0dd3aed21d34009aecf056a6f4a (patch) | |
| tree | 934ddffe61c86bb25393cefc2db09e7a5fb2d569 | |
| parent | 7912c0fdbec588732e52bea1bd315ff6d102a15f (diff) | |
| download | chrome-ec-a6c2477aca71c0dd3aed21d34009aecf056a6f4a.tar.gz | |
chip/stm32: Fix bug that LPTIM_PERIOD_US became unsigned long.
Due to a refactoring of bit shifts (BIT macro), LPTIM_PERIOD_US changed
from int to unsigned int, which in turn changed behavior of
set_lptim_event. This causes a watchdog reset during a long suspend. In
particular, this caused the stm32h7 FPMCU to reboot during long suspend
and fingerprint unlock to not work.
BUG=b:140538084
BRANCH=none
TEST=verified that FPMCU no longer reboots during deep sleep, fingerprint
unlock works after deep sleeping for a whole night.
Change-Id: If2ed9cb94aad4216012e28ffec530bc4ce858093
Signed-off-by: Yicheng Li <yichengli@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1854785
Reviewed-by: Nicolas Norvez <norvez@chromium.org>
| -rw-r--r-- | chip/stm32/clock-stm32h7.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/chip/stm32/clock-stm32h7.c b/chip/stm32/clock-stm32h7.c index a3ebb9aa36..f41a76b87a 100644 --- a/chip/stm32/clock-stm32h7.c +++ b/chip/stm32/clock-stm32h7.c @@ -32,7 +32,13 @@ * with /4 prescaler (2^2): period 125 us, full range ~8s */ #define LPTIM_PRESCALER_LOG2 2 -#define LPTIM_PRESCALER BIT(LPTIM_PRESCALER_LOG2) +/* + * LPTIM_PRESCALER and LPTIM_PERIOD_US have to be signed, because we compare + * them to an int to decide whether to go to deep sleep. Simply using BIT() + * makes them unsigned, which causes a bug in deep sleep behavior. + * TODO(b/140538084): Explain exactly what the bug is. + */ +#define LPTIM_PRESCALER ((int)BIT(LPTIM_PRESCALER_LOG2)) #define LPTIM_PERIOD_US (SECOND / (STM32_LSI_CLOCK / LPTIM_PRESCALER)) /* |