Fix multiple charging issues on snow

This change fixes mutiple snow charging issues. Including:
  - disable i2c host auto selection
  - i2c_read8 got wrong output value
  - pmu CHARGE_EN control workaround

Signed-off-by: Rong Chang <rongchang@chromium.org>
BUG=chrome-os-partner:11010
TEST=Only test on snow dvt with AP turned off
  plug/unplug ac adapter and check charging led
  check console command 'battery'

Change-Id: I29d554b3daa4cfc538bd5bf5ba5233976d381861
Reviewed-on: https://gerrit.chromium.org/gerrit/26529
Tested-by: Rong Chang <rongchang@chromium.org>
Commit-Ready: Rong Chang <rongchang@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

5 files changed, 92 insertions, 20 deletions

diff --git a/board/snow/board.h b/board/snow/board.h
index 605a9f93bb..15db5a64d7 100644
--- a/board/snow/board.h
+++ b/board/snow/board.h
@@ -44,8 +44,9 @@
 /* Charging */
 #define CONFIG_SMART_BATTERY
 #define CONFIG_PMU_TPS65090
-#define CONFIG_I2C_HOST_AUTO
-#define I2C_PORT_HOST board_i2c_host_port()
+/* #define CONFIG_I2C_HOST_AUTO */
+/* #define I2C_PORT_HOST board_i2c_host_port() */
+#define I2C_PORT_HOST 1
 #define I2C_PORT_BATTERY I2C_PORT_HOST
 #define I2C_PORT_CHARGER I2C_PORT_HOST
 #define I2C_PORT_SLAVE 1
diff --git a/chip/stm32/i2c.c b/chip/stm32/i2c.c
index bf34f5a466..f9fd2bd144 100644
--- a/chip/stm32/i2c.c
+++ b/chip/stm32/i2c.c
@@ -621,13 +621,13 @@ int i2c_write16(int port, int slave_addr, int offset, int data)
 
 int i2c_read8(int port, int slave_addr, int offset, int *data)
 {
-	uint8_t reg, buf[2];
+	uint8_t reg, buf[1];
 	int rv;
 
 	reg = offset & 0xff;
-	rv = i2c_xfer(port, slave_addr, &reg, 1, buf, 2);
+	rv = i2c_xfer(port, slave_addr, &reg, 1, buf, 1);
 
-	*data = buf[1];
+	*data = buf[0];
 
 	return rv;
 }
diff --git a/common/pmu_tps65090.c b/common/pmu_tps65090.c
index 290db145b3..93d9886699 100644
--- a/common/pmu_tps65090.c
+++ b/common/pmu_tps65090.c
@@ -29,6 +29,9 @@
 #define CG_STATUS1 0x0a
 #define CG_STATUS2 0x0b
 
+/* Charger control */
+#define CG_CTRL0_EN   1
+
 /* IRQ events */
 #define EVENT_VACG    (1 <<  1)
 #define EVENT_VBATG   (1 <<  3)
@@ -108,6 +111,22 @@ int pmu_get_power_source(int *ac_good, int *battery_good)
 	return EC_SUCCESS;
 }
 
+int pmu_enable_charger(int enable)
+{
+	int rv;
+	int reg;
+
+	rv = pmu_read(CG_CTRL0, &reg);
+	if (rv)
+		return rv;
+
+	if (reg & CG_CTRL0_EN)
+		return EC_SUCCESS;
+
+	return pmu_write(CG_CTRL0, enable ? (reg | CG_CTRL0_EN) :
+			(reg & ~CG_CTRL0));
+}
+
 void pmu_init(void)
 {
 	/* Init configuration
diff --git a/common/pmu_tps65090_charger.c b/common/pmu_tps65090_charger.c
index db13247050..bb473b5c2a 100644
--- a/common/pmu_tps65090_charger.c
+++ b/common/pmu_tps65090_charger.c
@@ -55,6 +55,8 @@ static void enable_charging(int enable)
 	enable = enable ? 1 : 0;
 	if (gpio_get_level(GPIO_CHARGER_EN) != enable)
 		gpio_set_level(GPIO_CHARGER_EN, enable);
+
+	pmu_enable_charger(enable);
 }
 
 
@@ -168,45 +170,57 @@ static int notify_battery_low(void)
 
 static int calc_next_state(int state)
 {
-	int batt_temp, alarm, capacity;
+	int batt_temp, alarm, capacity, charge;
 
 	switch (state) {
 	case ST_IDLE:
-		/* Turn off charger */
-		enable_charging(0);
 
 		/* Check AC and chiset state */
 		if (!get_ac()) {
 			if (chipset_in_state(CHIPSET_STATE_ON))
 				return ST_DISCHARGING;
-			return ST_IDLE;
+
+			/* Enable charging and wait ac on */
+			enable_charging(1);
+			return wait_t1_idle();
 		}
 
 		/* Enable charging when battery doesn't respond */
-		if (battery_temperature(&batt_temp))
+		if (battery_temperature(&batt_temp)) {
+			enable_charging(1);
+			wait_t1_idle();
 			return ST_PRE_CHARGING;
+		}
 
-		if (!battery_start_charging_range(batt_temp))
+		/* Turn off charger when battery temperature is out
+		 * of the start charging range.
+		 */
+		if (!battery_start_charging_range(batt_temp)) {
+			enable_charging(0);
 			return wait_t1_idle();
+		}
 
+		/* Turn off charger on battery charging alarm */
 		if (battery_status(&alarm) || (alarm & ALARM_CHARGING)) {
 			if (!(alarm & ALARM_TERMINATE_CHARGE))
 				CPRINTF("[pmu] idle %016b\n", alarm);
+			enable_charging(0);
 			return wait_t1_idle();
 		}
 
-		enable_charging(1);
-		return ST_CHARGING;
+		/* Start charging only when battery charge lower than 100% */
+		if (!battery_state_of_charge(&charge) && charge < 100) {
+			enable_charging(1);
+			wait_t1_idle();
+			return ST_CHARGING;
+		}
+
+		return wait_t1_idle();
 
 	case ST_PRE_CHARGING:
 		if (!get_ac())
 			return wait_t1_idle();
 
-		if (!gpio_get_level(GPIO_CHARGER_EN)) {
-			CPUTS("[pmu] try charging\n");
-			enable_charging(1);
-		}
-
 		/* If the battery goes online after enable the charger,
 		 * go into charging state.
 		 */
@@ -237,7 +251,7 @@ static int calc_next_state(int state)
 	case ST_DISCHARGING:
 
 		if (get_ac())
-			return ST_IDLE;
+			return wait_t1_idle();
 
 		/* Check battery discharging temperature range */
 		if (battery_temperature(&batt_temp) == 0) {
@@ -259,7 +273,7 @@ static int calc_next_state(int state)
 		return wait_t3_discharging();
 	}
 
-	return ST_IDLE;
+	return wait_t1_idle();
 }
 
 void pmu_charger_task(void)
diff --git a/include/pmu_tpschrome.h b/include/pmu_tpschrome.h
index 697e9942d5..0c066beff0 100644
--- a/include/pmu_tpschrome.h
+++ b/include/pmu_tpschrome.h
@@ -8,9 +8,47 @@
 #ifndef __CROS_EC_TPSCHROME_H
 #define __CROS_EC_TPSCHROME_H
 
+#define FET_BACKLIGHT 1
+#define FET_LCD_PANEL 6
 
+/**
+ * Check pmu charger alarm
+ *
+ * @return 0 if there's no charging alarm or pmu access failed
+ * @return 1 if charger over current or over heat
+ */
 int pmu_is_charger_alarm(void);
+
+/**
+ * Get pmu power source
+ *
+ * @param ac_good	pointer to output value of ac voltage good
+ * @param battery_good	pointer to output value of battery voltage good
+ * @return EC_SUCCESS if ac_good and battery_good are set
+ */
 int pmu_get_power_source(int *ac_good, int *battery_good);
+
+/**
+ * Enable/disable pmu fet
+ *
+ * @param fet_id	the fet to control
+ * @param enable	0 to disable the fet, 1 to enable
+ * @param power_good	pointer to value of fet power good
+ * @return		EC_SUCCESS if the communication to pmu succeeded
+ */
+int pmu_enable_fet(int fet_id, int enable, int *power_good);
+
+/**
+ * Enable/disable pmu internal charger
+ *
+ * @param enable        0 to disable the charger, 1 to enable
+ * @return              EC_SUCCESS if no I2C communication error
+ */
+int pmu_enable_charger(int enable);
+
+/**
+ *  * Initialize pmu
+ *   */
 void pmu_init(void);
 
 #endif /* __CROS_EC_TPSCHROME_H */