bq20z75: Add support for more power supply properties

This patch adds properties to support devicekit power. Also, create IO
wrapper functions and fix some issues found while testing, including
unit conversions to match the power_supply types.

Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>

drivers/power/bq20z75.c

@@ -36,7 +36,11 @@ enum {
 	REG_TIME_TO_FULL,
 	REG_STATUS,
 	REG_CYCLE_COUNT,
-	REG_SERIAL_NUMBER
+	REG_SERIAL_NUMBER,
+	REG_REMAINING_CAPACITY,
+	REG_FULL_CHARGE_CAPACITY,
+	REG_DESIGN_CAPACITY,
+	REG_DESIGN_VOLTAGE,
 };
 
 /* manufacturer access defines */
@@ -44,7 +48,7 @@ enum {
 #define MANUFACTURER_ACCESS_SLEEP	0x0011
 
 /* battery status value bits */
-#define BATTERY_CHARGING		0x40
+#define BATTERY_DISCHARGING		0x40
 #define BATTERY_FULL_CHARGED		0x20
 #define BATTERY_FULL_DISCHARGED		0x10
 
@@ -72,6 +76,10 @@ static const struct bq20z75_device_data {
 			32767),
 	[REG_CAPACITY] =
 		BQ20Z75_DATA(POWER_SUPPLY_PROP_CAPACITY, 0x0E, 0, 100),
+	[REG_REMAINING_CAPACITY] =
+		BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_NOW, 0x0F, 0, 65535),
+	[REG_FULL_CHARGE_CAPACITY] =
+		BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_FULL, 0x10, 0, 65535),
 	[REG_TIME_TO_EMPTY] =
 		BQ20Z75_DATA(POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, 0x12, 0,
 			65535),
@@ -82,6 +90,12 @@ static const struct bq20z75_device_data {
 		BQ20Z75_DATA(POWER_SUPPLY_PROP_STATUS, 0x16, 0, 65535),
 	[REG_CYCLE_COUNT] =
 		BQ20Z75_DATA(POWER_SUPPLY_PROP_CYCLE_COUNT, 0x17, 0, 65535),
+	[REG_DESIGN_CAPACITY] =
+		BQ20Z75_DATA(POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN, 0x18, 0,
+			65535),
+	[REG_DESIGN_VOLTAGE] =
+		BQ20Z75_DATA(POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, 0x19, 0,
+			65535),
 	[REG_SERIAL_NUMBER] =
 		BQ20Z75_DATA(POWER_SUPPLY_PROP_SERIAL_NUMBER, 0x1C, 0, 65535),
 };
@@ -99,6 +113,10 @@ static enum power_supply_property bq20z75_properties[] = {
 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
 	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
+	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+	POWER_SUPPLY_PROP_ENERGY_NOW,
+	POWER_SUPPLY_PROP_ENERGY_FULL,
+	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
 };
 
 struct bq20z75_info {
@@ -106,6 +124,35 @@ struct bq20z75_info {
 	struct power_supply	power_supply;
 };
 
+static int bq20z75_read_word_data(struct i2c_client *client, u8 address)
+{
+	s32 ret;
+
+	ret = i2c_smbus_read_word_data(client, address);
+	if (ret < 0) {
+		dev_err(&client->dev,
+			"%s: i2c read at address 0x%x failed\n",
+			__func__, address);
+		return ret;
+	}
+	return le16_to_cpu(ret);
+}
+
+static int bq20z75_write_word_data(struct i2c_client *client, u8 address,
+	u16 value)
+{
+	s32 ret;
+
+	ret = i2c_smbus_write_word_data(client, address, le16_to_cpu(value));
+	if (ret < 0) {
+		dev_err(&client->dev,
+			"%s: i2c write to address 0x%x failed\n",
+			__func__, address);
+		return ret;
+	}
+	return 0;
+}
+
 static int bq20z75_get_battery_presence_and_health(
 	struct i2c_client *client, enum power_supply_property psp,
 	union power_supply_propval *val)
@@ -115,24 +162,17 @@ static int bq20z75_get_battery_presence_and_health(
 	/* Write to ManufacturerAccess with
 	 * ManufacturerAccess command and then
 	 * read the status */
-	ret = i2c_smbus_write_word_data(client,
+	ret = bq20z75_write_word_data(client,
 		bq20z75_data[REG_MANUFACTURER_DATA].addr,
 		MANUFACTURER_ACCESS_STATUS);
-	if (ret < 0) {
-		dev_err(&client->dev,
-			"%s: i2c write for battery presence failed\n",
-			__func__);
-		return -ENODEV;
-	}
+	if (ret < 0)
+		return ret;
 
-	ret = i2c_smbus_read_word_data(client,
+
+	ret = bq20z75_read_word_data(client,
 		bq20z75_data[REG_MANUFACTURER_DATA].addr);
-	if (ret < 0) {
-		dev_err(&client->dev,
-			"%s: i2c read for battery presence failed\n",
-			__func__);
-		return -EIO;
-	}
+	if (ret < 0)
+		return ret;
 
 	if (ret < bq20z75_data[REG_MANUFACTURER_DATA].min_value ||
 	    ret > bq20z75_data[REG_MANUFACTURER_DATA].max_value) {
@@ -171,31 +211,28 @@ static int bq20z75_get_battery_property(struct i2c_client *client,
 {
 	s32 ret;
 
-	ret = i2c_smbus_read_word_data(client,
+	ret = bq20z75_read_word_data(client,
 		bq20z75_data[reg_offset].addr);
-	if (ret < 0) {
-		dev_err(&client->dev,
-			"%s: i2c read for %d failed\n", __func__, reg_offset);
-		return -EIO;
-	}
+	if (ret < 0)
+		return ret;
+
+	/* returned values are 16 bit */
+	if (bq20z75_data[reg_offset].min_value < 0)
+		ret = (s16)ret;
 
 	if (ret >= bq20z75_data[reg_offset].min_value &&
 	    ret <= bq20z75_data[reg_offset].max_value) {
 		val->intval = ret;
 		if (psp == POWER_SUPPLY_PROP_STATUS) {
-			if (ret & BATTERY_CHARGING)
-				val->intval = POWER_SUPPLY_STATUS_CHARGING;
-			else if (ret & BATTERY_FULL_CHARGED)
+			if (ret & BATTERY_FULL_CHARGED)
 				val->intval = POWER_SUPPLY_STATUS_FULL;
 			else if (ret & BATTERY_FULL_DISCHARGED)
 				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
-			else
+			else if (ret & BATTERY_DISCHARGING)
 				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+			else
+				val->intval = POWER_SUPPLY_STATUS_CHARGING;
 		}
-		/* bq20z75 provides battery tempreture in 0.1°K
-		 * so convert it to °C */
-		else if (psp == POWER_SUPPLY_PROP_TEMP)
-			val->intval = ret - 2731;
 	} else {
 		if (psp == POWER_SUPPLY_PROP_STATUS)
 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
@@ -206,21 +243,77 @@ static int bq20z75_get_battery_property(struct i2c_client *client,
 	return 0;
 }
 
+static void  bq20z75_unit_adjustment(struct i2c_client *client,
+	enum power_supply_property psp, union power_supply_propval *val)
+{
+#define BASE_UNIT_CONVERSION		1000
+#define BATTERY_MODE_CAP_MULT_WATT	(10 * BASE_UNIT_CONVERSION)
+#define TIME_UNIT_CONVERSION		600
+#define TEMP_KELVIN_TO_CELCIUS		2731
+	switch (psp) {
+	case POWER_SUPPLY_PROP_ENERGY_NOW:
+	case POWER_SUPPLY_PROP_ENERGY_FULL:
+	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
+		val->intval *= BATTERY_MODE_CAP_MULT_WATT;
+		break;
+
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+	case POWER_SUPPLY_PROP_CURRENT_NOW:
+		val->intval *= BASE_UNIT_CONVERSION;
+		break;
+
+	case POWER_SUPPLY_PROP_TEMP:
+		/* bq20z75 provides battery tempreture in 0.1°K
+		 * so convert it to 0.1°C */
+		val->intval -= TEMP_KELVIN_TO_CELCIUS;
+		val->intval *= 10;
+		break;
+
+	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
+	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
+		val->intval *= TIME_UNIT_CONVERSION;
+		break;
+
+	default:
+		dev_dbg(&client->dev,
+			"%s: no need for unit conversion %d\n", __func__, psp);
+	}
+}
+
 static int bq20z75_get_battery_capacity(struct i2c_client *client,
+	int reg_offset, enum power_supply_property psp,
 	union power_supply_propval *val)
 {
 	s32 ret;
 
-	ret = i2c_smbus_read_byte_data(client, bq20z75_data[REG_CAPACITY].addr);
-	if (ret < 0) {
-		dev_err(&client->dev,
-			"%s: i2c read for %d failed\n", __func__, REG_CAPACITY);
-		return -EIO;
-	}
+	ret = bq20z75_read_word_data(client, bq20z75_data[reg_offset].addr);
+	if (ret < 0)
+		return ret;
 
-	/* bq20z75 spec says that this can be >100 %
-	 * even if max value is 100 % */
-	val->intval = min(ret, 100);
+	if (psp == POWER_SUPPLY_PROP_CAPACITY) {
+		/* bq20z75 spec says that this can be >100 %
+		* even if max value is 100 % */
+		val->intval = min(ret, 100);
+	} else
+		val->intval = ret;
+
+	return 0;
+}
+
+static char bq20z75_serial[5];
+static int bq20z75_get_battery_serial_number(struct i2c_client *client,
+	union power_supply_propval *val)
+{
+	int ret;
+
+	ret = bq20z75_read_word_data(client,
+		bq20z75_data[REG_SERIAL_NUMBER].addr);
+	if (ret < 0)
+		return ret;
+
+	ret = sprintf(bq20z75_serial, "%04x", ret);
+	val->strval = bq20z75_serial;
 
 	return 0;
 }
@@ -247,8 +340,23 @@ static int bq20z75_get_property(struct power_supply *psy,
 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
 		break;
 
+	case POWER_SUPPLY_PROP_ENERGY_NOW:
+	case POWER_SUPPLY_PROP_ENERGY_FULL:
+	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
 	case POWER_SUPPLY_PROP_CAPACITY:
-		ret = bq20z75_get_battery_capacity(client, val);
+		for (count = 0; count < ARRAY_SIZE(bq20z75_data); count++) {
+			if (psp == bq20z75_data[count].psp)
+				break;
+		}
+
+		ret = bq20z75_get_battery_capacity(client, count, psp, val);
+		if (ret)
+			return ret;
+
+		break;
+
+	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
+		ret = bq20z75_get_battery_serial_number(client, val);
 		if (ret)
 			return ret;
 		break;
@@ -260,7 +368,7 @@ static int bq20z75_get_property(struct power_supply *psy,
 	case POWER_SUPPLY_PROP_TEMP:
 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
 	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
-	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
+	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
 		for (count = 0; count < ARRAY_SIZE(bq20z75_data); count++) {
 			if (psp == bq20z75_data[count].psp)
 				break;
@@ -269,6 +377,7 @@ static int bq20z75_get_property(struct power_supply *psy,
 		ret = bq20z75_get_battery_property(client, count, psp, val);
 		if (ret)
 			return ret;
+
 		break;
 
 	default:
@@ -277,6 +386,9 @@ static int bq20z75_get_property(struct power_supply *psy,
 		return -EINVAL;
 	}
 
+	/* Convert units to match requirements for power supply class */
+	bq20z75_unit_adjustment(client, psp, val);
+
 	dev_dbg(&client->dev,
 		"%s: property = %d, value = %d\n", __func__, psp, val->intval);
 
@@ -335,15 +447,11 @@ static int bq20z75_suspend(struct i2c_client *client,
 	s32 ret;
 
 	/* write to manufacturer access with sleep command */
-	ret = i2c_smbus_write_word_data(client,
+	ret = bq20z75_write_word_data(client,
 		bq20z75_data[REG_MANUFACTURER_DATA].addr,
 		MANUFACTURER_ACCESS_SLEEP);
-	if (ret < 0) {
-		dev_err(&client->dev,
-			"%s: i2c write for %d failed\n",
-			__func__, MANUFACTURER_ACCESS_SLEEP);
-		return -EIO;
-	}
+	if (ret < 0)
+		return ret;
 
 	return 0;
 }