battery/max17055: Update batt_param as a whole.

Clearing batt_param everytime when calling battery_get_params may cause
AP getting weird battery information through host_command due to
preemption.  We should update the batt_param as a whole.

BUG=b:119322063, b:73347743, b:117061273
TEST=on kukui, remove batt, connect pd, see battery output in console
> batt
  Status:    0x0040 DCHG
  Param flags:00000000
  Temp:      0x0000 = 0.0 K (-273.1 C)
  V:         0x0000 = 0 mV
  V-desired: 0x0000 = 0 mV
  I:         0x0000 = 0 mA
  I-desired: 0x0000 = 0 mA
  Charging:  Not Allowed
  Charge:    0 %
  Manuf:     <unkn>
  Device:    <BATT>
  Chem:      <unkn>
  Serial:    0xffffffff
  V-design:  0x0f14 = 3860 mV
  Mode:      (unsupported)
  Abs charge:(unsupported)
  Remaining: 6355 mAh
  Cap-full:  6910 mAh (6771 mAh with 98 % compensation)
  Display:   0.0 %
    Design:  6910 mAh
  Time-full: 102h:23
    Empty:   102h:23
TEST=on connect batt, connect pd, see battery output in console
> batt
  Status:    0x0000
  Param flags:00000003
  Temp:      0x0bae = 299.0 K (25.9 C)
  V:         0x0ef4 = 3828 mV
  V-desired: 0x1130 = 4400 mV
  I:         0x0067 = 103 mA(CHG)
  I-desired: 0x07d0 = 2000 mA
  Charging:  Allowed
  Charge:    49 %
  Manuf:     <unkn>
  Device:    <BATT>
  Chem:      <unkn>
  Serial:    0xffffffff
  V-design:  0x0f14 = 3860 mV
  Mode:      (unsupported)
  Abs charge:(unsupported)
  Remaining: 3440 mAh
  Cap-full:  6910 mAh (6771 mAh with 98 % compensation)
  Display:   0.0 %
    Design:  6910 mAh
  Time-full: 0h:0
    Empty:   102h:23
BRANCH=None

Change-Id: I752a3842e6ca54dc8cad98a1099387e0088cc48d
Signed-off-by: Yilun Lin <yllin@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1345551
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Yilun Lin <yllin@chromium.org>
Reviewed-by: Philip Chen <philipchen@chromium.org>
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>

1 files changed, 32 insertions, 29 deletions

diff --git a/driver/battery/max17055.c b/driver/battery/max17055.c
index 9cdd107d20..1b5679fe37 100644
--- a/driver/battery/max17055.c
+++ b/driver/battery/max17055.c
@@ -263,64 +263,67 @@ enum battery_present battery_is_present(void)
 void battery_get_params(struct batt_params *batt)
 {
 	int reg = 0;
+	struct batt_params batt_new = {0};
 
-	/* Reset params */
-	memset(batt, 0, sizeof(struct batt_params));
 	/*
 	 * Assuming the battery is responsive as long as
 	 * max17055 finds battery is present.
 	 */
-	batt->is_present = battery_is_present();
+	batt_new.is_present = battery_is_present();
 
-	if (batt->is_present == BP_YES)
-		batt->flags |= BATT_FLAG_RESPONSIVE;
-	else if (batt->is_present == BP_NO)
+	if (batt_new.is_present == BP_YES)
+		batt_new.flags |= BATT_FLAG_RESPONSIVE;
+	else if (batt_new.is_present == BP_NO)
 		/* Battery is not present, gauge won't report useful info. */
-		return;
+		goto batt_out;
 
 	if (max17055_read(REG_TEMPERATURE, &reg))
-		batt->flags |= BATT_FLAG_BAD_TEMPERATURE;
+		batt_new.flags |= BATT_FLAG_BAD_TEMPERATURE;
 
-	batt->temperature = TEMPERATURE_CONV((int16_t)reg);
+	batt_new.temperature = TEMPERATURE_CONV((int16_t)reg);
 
 	if (max17055_read(REG_STATE_OF_CHARGE, &reg) &&
 	    fake_state_of_charge < 0)
-		batt->flags |= BATT_FLAG_BAD_STATE_OF_CHARGE;
+		batt_new.flags |= BATT_FLAG_BAD_STATE_OF_CHARGE;
 
-	batt->state_of_charge = fake_state_of_charge >= 0 ?
+	batt_new.state_of_charge = fake_state_of_charge >= 0 ?
 				fake_state_of_charge : PERCENTAGE_CONV(reg);
 
 	if (max17055_read(REG_VOLTAGE, &reg))
-		batt->flags |= BATT_FLAG_BAD_VOLTAGE;
+		batt_new.flags |= BATT_FLAG_BAD_VOLTAGE;
 
-	batt->voltage = VOLTAGE_CONV(reg);
+	batt_new.voltage = VOLTAGE_CONV(reg);
 
 	if (max17055_read(REG_CURRENT, &reg))
-		batt->flags |= BATT_FLAG_BAD_CURRENT;
+		batt_new.flags |= BATT_FLAG_BAD_CURRENT;
 
-	batt->current = CURRENT_CONV((int16_t)reg);
+	batt_new.current = CURRENT_CONV((int16_t)reg);
 
-	batt->desired_voltage = battery_get_info()->voltage_max;
-	batt->desired_current = BATTERY_DESIRED_CHARGING_CURRENT;
+	batt_new.desired_voltage = battery_get_info()->voltage_max;
+	batt_new.desired_current = BATTERY_DESIRED_CHARGING_CURRENT;
 
-	if (battery_remaining_capacity(&batt->remaining_capacity))
-		batt->flags |= BATT_FLAG_BAD_REMAINING_CAPACITY;
+	if (battery_remaining_capacity(&batt_new.remaining_capacity))
+		batt_new.flags |= BATT_FLAG_BAD_REMAINING_CAPACITY;
 
-	if (battery_full_charge_capacity(&batt->full_capacity))
-		batt->flags |= BATT_FLAG_BAD_FULL_CAPACITY;
+	if (battery_full_charge_capacity(&batt_new.full_capacity))
+		batt_new.flags |= BATT_FLAG_BAD_FULL_CAPACITY;
 
 	/*
 	 * Charging allowed if both desired voltage and current are nonzero
 	 * and battery isn't full (and we read them all correctly).
 	 */
-	if (!(batt->flags & BATT_FLAG_BAD_STATE_OF_CHARGE) &&
-	    batt->desired_voltage &&
-	    batt->desired_current &&
-	    batt->state_of_charge < BATTERY_LEVEL_FULL)
-		batt->flags |= BATT_FLAG_WANT_CHARGE;
-
-	if (battery_status(&batt->status))
-		batt->flags |= BATT_FLAG_BAD_STATUS;
+	if (!(batt_new.flags & BATT_FLAG_BAD_STATE_OF_CHARGE) &&
+	    batt_new.desired_voltage &&
+	    batt_new.desired_current &&
+	    batt_new.state_of_charge < BATTERY_LEVEL_FULL)
+		batt_new.flags |= BATT_FLAG_WANT_CHARGE;
+
+	if (battery_status(&batt_new.status))
+		batt_new.flags |= BATT_FLAG_BAD_STATUS;
+
+batt_out:
+	/* Update visible battery parameters */
+	memcpy(batt, &batt_new, sizeof(*batt));
 }
 
 #ifdef CONFIG_CMD_PWR_AVG