Include battery fuel gauge temp sensor in temperature sensors

This gives the AP a way to see that temperature for DPTF.  Alarm
thresholds were defined on a per-sensor basis, so they come along for
free.

BUG=chrome-os-partner:25585
BRANCH=rambi
TEST=temps command shows same temp for battery as battery command (other
     than rounding error; battery command shows with 0.1C accuracy).
     'ectool temps all' shows the battery temp as the last temperature.

     Unplug battery and temps command shows error for the battery temp,
     as does 'ectool temps all'.

Change-Id: I1bce72f164d9fb1be631e7241a4ea24ddf409d7a
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/185444
Reviewed-by: Dave Parker <dparker@chromium.org>

5 files changed, 30 insertions, 0 deletions

diff --git a/board/rambi/board.c b/board/rambi/board.c
index cdef1c11b1..d4497d9901 100644
--- a/board/rambi/board.c
+++ b/board/rambi/board.c
@@ -7,6 +7,7 @@
 #include "adc.h"
 #include "adc_chip.h"
 #include "backlight.h"
+#include "charge_state.h"
 #include "charger.h"
 #include "common.h"
 #include "driver/temp_sensor/tmp432.h"
@@ -185,6 +186,7 @@ const struct temp_sensor_t temp_sensors[] = {
 		TMP432_IDX_REMOTE1, 4},
 	{"TMP432_CPU_bottom", TEMP_SENSOR_TYPE_BOARD, tmp432_get_val,
 		TMP432_IDX_REMOTE2, 4},
+	{"Battery", TEMP_SENSOR_TYPE_BATTERY, charge_temp_sensor_get_val, 0, 4},
 };
 BUILD_ASSERT(ARRAY_SIZE(temp_sensors) == TEMP_SENSOR_COUNT);
 
@@ -196,6 +198,7 @@ struct ec_thermal_config thermal_params[] = {
 	{{0, 0, 0}, 0, 0},
 	{{0, 0, 0}, 0, 0},
 	{{0, 0, 0}, 0, 0},
+	{{0, 0, 0}, 0, 0},
 };
 BUILD_ASSERT(ARRAY_SIZE(thermal_params) == TEMP_SENSOR_COUNT);
 
diff --git a/board/rambi/board.h b/board/rambi/board.h
index 95736b2e09..091c9d9d04 100644
--- a/board/rambi/board.h
+++ b/board/rambi/board.h
@@ -179,6 +179,9 @@ enum temp_sensor_id {
 	TEMP_SENSOR_I2C_TMP432_REMOTE1,
 	TEMP_SENSOR_I2C_TMP432_REMOTE2,
 
+	/* Battery temperature sensor */
+	TEMP_SENSOR_BATTERY,
+
 	TEMP_SENSOR_COUNT
 };
 
diff --git a/common/charge_state.c b/common/charge_state.c
index 16bb69b428..53c1dda5d2 100644
--- a/common/charge_state.c
+++ b/common/charge_state.c
@@ -664,6 +664,17 @@ int charge_get_percent(void)
 	return task_ctx.curr.batt.state_of_charge;
 }
 
+int charge_temp_sensor_get_val(int idx, int *temp_ptr)
+{
+	const struct batt_params *batt = &task_ctx.curr.batt;
+
+	if (!(batt->flags & BATT_FLAG_RESPONSIVE))
+		return EC_ERROR_UNKNOWN;
+
+	*temp_ptr = C_TO_K(DECI_KELVIN_TO_CELSIUS(batt->temperature));
+	return EC_SUCCESS;
+}
+
 int charge_want_shutdown(void)
 {
 	return (charge_get_state() == PWR_STATE_DISCHARGE) &&
diff --git a/include/charge_state.h b/include/charge_state.h
index 7aaf77b93d..152e767295 100644
--- a/include/charge_state.h
+++ b/include/charge_state.h
@@ -143,5 +143,16 @@ int charge_want_shutdown(void);
 #else
 static inline int charge_want_shutdown(void) { return 0; }
 #endif
+
+/**
+ * Get the last polled battery/charger temperature.
+ *
+ * @param idx		Sensor index to read.
+ * @param temp_ptr	Destination for temperature in K.
+ *
+ * @return EC_SUCCESS if successful, non-zero if error.
+ */
+int charge_temp_sensor_get_val(int idx, int *temp_ptr);
+
 #endif /* __CROS_EC_CHARGE_STATE_H */
 
diff --git a/include/temp_sensor.h b/include/temp_sensor.h
index cd1b80d892..61f218d5d7 100644
--- a/include/temp_sensor.h
+++ b/include/temp_sensor.h
@@ -23,6 +23,8 @@ enum temp_sensor_type {
 	TEMP_SENSOR_TYPE_BOARD,
 	/* Case temperature sensors. */
 	TEMP_SENSOR_TYPE_CASE,
+	/* Battery temperature sensors. */
+	TEMP_SENSOR_TYPE_BATTERY,
 
 	TEMP_SENSOR_TYPE_COUNT
 };