power: supply: bq27xxx: Support CHARGE_NOW for bq27z561/bq28z610/bq34z100

Currently REG_NAC (nominal available capacity) is mapped to
power-supply's CHARGE_NOW property. Some chips do not have
REG_NAC and do not expose CHARGE_NOW at the moment. Some
bq27xxx chips also have another register REG_RM (remaining
capacity). The difference between REG_NAC and REG_RM is load
compensation.

This patch adds register information for REG_RM for all
supported fuel gauges. On systems having REG_NAC it is
ignored, so behaviour does not change. On systems without
REG_NAC, REG_RM will be used to provide CHARGE_NOW
functionality.

As a result there are three more chips exposing CHARGE_NOW:
bq27z561, bq28z610 and bq34z100

Signed-off-by: Hermes Zhang <chenhuiz@axis.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

1 files changed, 34 insertions, 1 deletions

diff --git a/drivers/power/supply/bq27xxx_battery.c b/drivers/power/supply/bq27xxx_battery.c
index 315e0909e6a4..774aa376653e 100644
--- a/drivers/power/supply/bq27xxx_battery.c
+++ b/drivers/power/supply/bq27xxx_battery.c
@@ -110,6 +110,7 @@ enum bq27xxx_reg_index {
 	BQ27XXX_REG_TTES,	/* Time-to-Empty Standby */
 	BQ27XXX_REG_TTECP,	/* Time-to-Empty at Constant Power */
 	BQ27XXX_REG_NAC,	/* Nominal Available Capacity */
+	BQ27XXX_REG_RC,		/* Remaining Capacity */
 	BQ27XXX_REG_FCC,	/* Full Charge Capacity */
 	BQ27XXX_REG_CYCT,	/* Cycle Count */
 	BQ27XXX_REG_AE,		/* Available Energy */
@@ -145,6 +146,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1c,
 		[BQ27XXX_REG_TTECP] = 0x26,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = 0x22,
@@ -169,6 +171,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1c,
 		[BQ27XXX_REG_TTECP] = 0x26,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -193,6 +196,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1a,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -215,6 +219,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1c,
 		[BQ27XXX_REG_TTECP] = 0x26,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = 0x22,
@@ -237,6 +242,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1a,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x1e,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -257,6 +263,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1c,
 		[BQ27XXX_REG_TTECP] = 0x26,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_AE] = 0x22,
@@ -277,6 +284,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1c,
 		[BQ27XXX_REG_TTECP] = 0x26,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = 0x22,
@@ -297,6 +305,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1c,
 		[BQ27XXX_REG_TTECP] = 0x26,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = 0x22,
@@ -317,6 +326,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1c,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x1e,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -337,6 +347,7 @@ static u8
 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = INVALID_REG_ADDR,
+		[BQ27XXX_REG_RC] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_FCC] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_CYCT] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -361,6 +372,7 @@ static u8
 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -382,6 +394,7 @@ static u8
 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -405,6 +418,7 @@ static u8
 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = 0x0c,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -425,6 +439,7 @@ static u8
 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = 0x08,
+		[BQ27XXX_REG_RC] = 0x0c,
 		[BQ27XXX_REG_FCC] = 0x0e,
 		[BQ27XXX_REG_CYCT] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
@@ -450,6 +465,7 @@ static u8
 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = INVALID_REG_ADDR,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = 0x22,
@@ -470,6 +486,7 @@ static u8
 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = INVALID_REG_ADDR,
+		[BQ27XXX_REG_RC] = 0x10,
 		[BQ27XXX_REG_FCC] = 0x12,
 		[BQ27XXX_REG_CYCT] = 0x2a,
 		[BQ27XXX_REG_AE] = 0x22,
@@ -490,6 +507,7 @@ static u8
 		[BQ27XXX_REG_TTES] = 0x1e,
 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
 		[BQ27XXX_REG_NAC] = INVALID_REG_ADDR,
+		[BQ27XXX_REG_RC] = 0x04,
 		[BQ27XXX_REG_FCC] = 0x06,
 		[BQ27XXX_REG_CYCT] = 0x2c,
 		[BQ27XXX_REG_AE] = 0x24,
@@ -745,6 +763,7 @@ static enum power_supply_property bq27z561_props[] = {
 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
 	POWER_SUPPLY_PROP_TECHNOLOGY,
 	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 	POWER_SUPPLY_PROP_CYCLE_COUNT,
 	POWER_SUPPLY_PROP_POWER_AVG,
@@ -764,6 +783,7 @@ static enum power_supply_property bq28z610_props[] = {
 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
 	POWER_SUPPLY_PROP_TECHNOLOGY,
 	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 	POWER_SUPPLY_PROP_CYCLE_COUNT,
 	POWER_SUPPLY_PROP_POWER_AVG,
@@ -784,6 +804,7 @@ static enum power_supply_property bq34z100_props[] = {
 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
 	POWER_SUPPLY_PROP_TECHNOLOGY,
 	POWER_SUPPLY_PROP_CHARGE_FULL,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
 	POWER_SUPPLY_PROP_CYCLE_COUNT,
 	POWER_SUPPLY_PROP_ENERGY_NOW,
@@ -1519,6 +1540,15 @@ static inline int bq27xxx_battery_read_nac(struct bq27xxx_device_info *di)
 }
 
 /*
+ * Return the battery Remaining Capacity in µAh
+ * Or < 0 if something fails.
+ */
+static inline int bq27xxx_battery_read_rc(struct bq27xxx_device_info *di)
+{
+	return bq27xxx_battery_read_charge(di, BQ27XXX_REG_RC);
+}
+
+/*
  * Return the battery Full Charge Capacity in µAh
  * Or < 0 if something fails.
  */
@@ -1965,7 +1995,10 @@ static int bq27xxx_battery_get_property(struct power_supply *psy,
 			val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 		break;
 	case POWER_SUPPLY_PROP_CHARGE_NOW:
-		ret = bq27xxx_simple_value(bq27xxx_battery_read_nac(di), val);
+		if (di->regs[BQ27XXX_REG_NAC] != INVALID_REG_ADDR)
+			ret = bq27xxx_simple_value(bq27xxx_battery_read_nac(di), val);
+		else
+			ret = bq27xxx_simple_value(bq27xxx_battery_read_rc(di), val);
 		break;
 	case POWER_SUPPLY_PROP_CHARGE_FULL:
 		ret = bq27xxx_simple_value(di->cache.charge_full, val);