diff options
| author | Vincent Palatin <vpalatin@chromium.org> | 2013-10-17 10:26:10 -0700 |
|---|---|---|
| committer | chrome-internal-fetch <chrome-internal-fetch@google.com> | 2013-10-21 19:25:06 +0000 |
| commit | b0494f87da3e838fb08f1583c368bee0fc32fb21 (patch) | |
| tree | 2a6cdf3b5229d1addebbe48d810772d2b897ded6 | |
| parent | 21db824efefde9237db0f92e6145a10bbdd47b53 (diff) | |
| download | chrome-ec-b0494f87da3e838fb08f1583c368bee0fc32fb21.tar.gz | |
spring: do not start CPU when battery is self cut-off
When the battery self cuts off due to a cell under-voltage, the battery
discharging FET is disabled but the gas gauge still advertise available
capacity.
The patch specifically detects that case and prevents the main CPU from
running since the battery is doing any power buffering until the DSG FET
is enabled.
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
BRANCH=spring
BUG=chrome-os-partner:22807
TEST=On spring, with two good battery (one somewhat charged, the other
discharged) successfully starts the machine plugged on Spring charger.
With a self cut-off battery, see the EC preventing the CPU start-up and
the system staying stable and charging the battery.
Change-Id: I1eec1a6f061bbf3b6e4ca996cecbe1ad76c0f29d
Reviewed-on: https://chromium-review.googlesource.com/173570
Reviewed-by: Puneet Kumar <puneetster@chromium.org>
Reviewed-by: Vic Yang <victoryang@chromium.org>
Commit-Queue: Vincent Palatin <vpalatin@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>
| -rw-r--r-- | common/pmu_tps65090_charger.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/common/pmu_tps65090_charger.c b/common/pmu_tps65090_charger.c index f5f9409cb0..4d24c5bef3 100644 --- a/common/pmu_tps65090_charger.c +++ b/common/pmu_tps65090_charger.c @@ -408,6 +408,28 @@ int charge_keep_power_off(void) { int charge; +#ifdef CONFIG_BATTERY_SPRING + int blk_opstatus; + int ret; + /* + * bq30z55 specific: reads OperationStatus register + * and checks the status of the discharging FET (DSG FET) + * if it is disabled, we cannot use the battery as a buffer + * whatever charge level it is returning. + */ + ret = sb_write(SB_MANUFACTURER_ACCESS, 0x54 /* OperationStatus */); + ret |= sb_read(SB_MANUFACTURER_DATA, &blk_opstatus); + /* DSG FET status is <bit 1> of OperationStatus register + * but this register is accessed using an SMBUS block transfer + * so the first byte is the size of the transfer rather than + * the first byte of data. + * if we can access OperationStatus register AND DSG FET is disabled, + * we stay off. + */ + if (!ret && !(blk_opstatus & (1 << (1 + 8)))) + return 1; +#endif + if (BATTERY_AP_OFF_LEVEL == 0) return 0; |