diff options
| -rw-r--r-- | chip/lm4/peci.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/chip/lm4/peci.c b/chip/lm4/peci.c index d3fbd30947..d66956202b 100644 --- a/chip/lm4/peci.c +++ b/chip/lm4/peci.c @@ -75,7 +75,15 @@ int peci_temp_sensor_get_val(int idx, int *temp_ptr) } } - if (!success_cnt) + /* + * Require at least two valid samples. When the AP transitions into S0, + * it is possible, depending on the timing of the PECI sample, to read + * an invalid temperature. This is very rare, but when it does happen + * the temperature returned is PECI_TJMAX. Requiring two valid samples + * here assures us that one bad maximum temperature reading when + * entering S0 won't cause us to trigger an over temperature. + */ + if (success_cnt < 2) return EC_ERROR_UNKNOWN; *temp_ptr = sum / success_cnt; |