flapjack: base on the adc to determine battery type

Use the ADC reading to match the battery in the table.

BUG=b:126770302
BRANCH=None
TEST=Check the console with matching "Battery Type:" value.

Change-Id: Ibdc9a96b7f15506deda6e87fec49270a7afe3441
Signed-off-by: YH Lin <yueherngl@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1507320
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>

2 files changed, 46 insertions, 12 deletions

diff --git a/board/flapjack/battery.c b/board/flapjack/battery.c
index 1e088f32d9..6ba167b3fe 100644
--- a/board/flapjack/battery.c
+++ b/board/flapjack/battery.c
@@ -19,9 +19,12 @@
 #include "usb_pd.h"
 #include "util.h"
 #include "board.h"
+#include "adc.h"
+#include "adc_chip.h"
+#include "math_util.h"
 
-/* We have only one battery now. */
-#define BATT_ID BATTERY_C18_ATL
+#define CPRINTS(format, args...) cprints(CC_USBCHARGE, format, ## args)
+#define CPRINTF(format, args...) cprintf(CC_USBCHARGE, format, ## args)
 
 #define BAT_LEVEL_PD_LIMIT 85
 
@@ -147,19 +150,52 @@ static const struct {
 	},
 };
 
+static struct {
+	enum battery_type type;
+	int expect_mv;
+} const batteries[] = {
+	{ BATTERY_C18_ATL,       900 },  /* 100K  */
+	{ BATTERY_C19_ATL,       576 },  /* 47K   */
+};
+BUILD_ASSERT(ARRAY_SIZE(batteries) < BATTERY_COUNT);
+
+#define MARGIN_MV 56 /* Simply assume 1800/16/2 */
+
+static enum battery_type batt_type = BATTERY_UNKNOWN;
+
+static void board_get_battery_type(void)
+{
+	int mv;
+	int i;
+
+	mv = adc_read_channel(ADC_BATT_ID);
+	if (mv == ADC_READ_ERROR)
+		mv = adc_read_channel(ADC_BATT_ID);
+
+	for (i = 0; i < ARRAY_SIZE(batteries); i++) {
+		if (ABS(mv - batteries[i].expect_mv) < MARGIN_MV) {
+			batt_type = batteries[i].type;
+			break;
+		}
+	}
+
+	CPRINTS("Battery Type: %d", batt_type);
+}
+DECLARE_HOOK(HOOK_INIT, board_get_battery_type, HOOK_PRIO_FIRST);
+
 const struct battery_info *battery_get_info(void)
 {
-	return &info[BATT_ID];
+	return &info[batt_type];
 }
 
 const struct max17055_batt_profile *max17055_get_batt_profile(void)
 {
-	return &batt_profile[BATT_ID];
+	return &batt_profile[batt_type];
 }
 
 const struct max17055_alert_profile *max17055_get_alert_profile(void)
 {
-	return &alert_profile[BATT_ID];
+	return &alert_profile[batt_type];
 }
 
 int board_cut_off_battery(void)
@@ -188,14 +224,14 @@ int charger_profile_override(struct charge_state_data *curr)
 		return 0;
 
 	if ((curr->batt.flags & BATT_FLAG_BAD_TEMPERATURE) ||
-	    (bat_temp_c < temp_zones[BATT_ID][0].temp_min) ||
-	    (bat_temp_c >= temp_zones[BATT_ID][TEMP_ZONE_COUNT - 1].temp_max))
+	    (bat_temp_c < temp_zones[batt_type][0].temp_min) ||
+	    (bat_temp_c >= temp_zones[batt_type][TEMP_ZONE_COUNT - 1].temp_max))
 		temp_zone = TEMP_OUT_OF_RANGE;
 	else {
 		for (temp_zone = TEMP_ZONE_0; temp_zone < TEMP_ZONE_COUNT;
 		     temp_zone++) {
 			if (bat_temp_c <
-				temp_zones[BATT_ID][temp_zone].temp_max)
+				temp_zones[batt_type][temp_zone].temp_max)
 				break;
 		}
 	}
@@ -206,9 +242,9 @@ int charger_profile_override(struct charge_state_data *curr)
 		curr->state = ST_IDLE;
 	} else {
 		curr->requested_current =
-			temp_zones[BATT_ID][temp_zone].desired_current;
+			temp_zones[batt_type][temp_zone].desired_current;
 		curr->requested_voltage =
-			temp_zones[BATT_ID][temp_zone].desired_voltage;
+			temp_zones[batt_type][temp_zone].desired_voltage;
 	}
 
 	/*
diff --git a/board/flapjack/board.c b/board/flapjack/board.c
index bcf1dbe98e..9c32886ffb 100644
--- a/board/flapjack/board.c
+++ b/board/flapjack/board.c
@@ -285,8 +285,6 @@ void board_config_pre_init(void)
 					  (3 << 20) | (3 << 24);
 }
 
-#define THRESHOLD_MV 56 /* Simply assume 1800/16/2 */
-
 /* Motion sensors */
 /* Mutexes */
 #ifdef SECTION_IS_RW