[PATCH v9 8/8] power: bq27xxx_battery_i2c: Add I2C bulk read/write functions

[Liam Breck <liam@networkimprov.net>]

From: Matt Ranostay <matt@ranostay.consulting>

write(), read_bulk(), write_bulk() are required by bq27xxx_battery
devicetree code.

Signed-off-by: Matt Ranostay <matt@ranostay.consulting>
Signed-off-by: Liam Breck <kernel@networkimprov.net>
---
 drivers/power/supply/bq27xxx_battery_i2c.c | 82 +++++++++++++++++++++++++++++-
 1 file changed, 81 insertions(+), 1 deletion(-)

diff --git a/drivers/power/supply/bq27xxx_battery_i2c.c b/drivers/power/supply/bq27xxx_battery_i2c.c
index 7781ca9..4039b9d 100644
--- a/drivers/power/supply/bq27xxx_battery_i2c.c
+++ b/drivers/power/supply/bq27xxx_battery_i2c.c
@@ -38,7 +38,7 @@ static int bq27xxx_battery_i2c_read(struct bq27xxx_device_info *di, u8 reg,
 {
 	struct i2c_client *client = to_i2c_client(di->dev);
 	struct i2c_msg msg[2];
-	unsigned char data[2];
+	u8 data[2];
 	int ret;
 
 	if (!client->adapter)
@@ -68,6 +68,82 @@ static int bq27xxx_battery_i2c_read(struct bq27xxx_device_info *di, u8 reg,
 	return ret;
 }
 
+static int bq27xxx_battery_i2c_write(struct bq27xxx_device_info *di, u8 reg,
+				     int value, bool single)
+{
+	struct i2c_client *client = to_i2c_client(di->dev);
+	struct i2c_msg msg;
+	u8 data[4];
+	int ret;
+
+	if (!client->adapter)
+		return -ENODEV;
+
+	data[0] = reg;
+	if (single) {
+		data[1] = (u8) value;
+		msg.len = 2;
+	} else {
+		put_unaligned_le16(value, &data[1]);
+		msg.len = 3;
+	}
+
+	msg.buf = data;
+	msg.addr = client->addr;
+	msg.flags = 0;
+
+	ret = i2c_transfer(client->adapter, &msg, 1);
+	if (ret < 0)
+		return ret;
+	if (ret != 1)
+		return -EINVAL;
+	return 0;
+}
+
+static int bq27xxx_battery_i2c_bulk_read(struct bq27xxx_device_info *di, u8 reg,
+					 u8 *data, int len)
+{
+	struct i2c_client *client = to_i2c_client(di->dev);
+	int ret;
+
+	if (!client->adapter)
+		return -ENODEV;
+
+	ret = i2c_smbus_read_i2c_block_data(client, reg, len, data);
+	if (ret < 0)
+		return ret;
+	if (ret != len)
+		return -EINVAL;
+	return 0;
+}
+
+static int bq27xxx_battery_i2c_bulk_write(struct bq27xxx_device_info *di,
+					  u8 reg, u8 *data, int len)
+{
+	struct i2c_client *client = to_i2c_client(di->dev);
+	struct i2c_msg msg;
+	u8 buf[33];
+	int ret;
+
+	if (!client->adapter)
+		return -ENODEV;
+
+	buf[0] = reg;
+	memcpy(&buf[1], data, len);
+
+	msg.buf = buf;
+	msg.addr = client->addr;
+	msg.flags = 0;
+	msg.len = len + 1;
+
+	ret = i2c_transfer(client->adapter, &msg, 1);
+	if (ret < 0)
+		return ret;
+	if (ret != 1)
+		return -EINVAL;
+	return 0;
+}
+
 static int bq27xxx_battery_i2c_probe(struct i2c_client *client,
 				     const struct i2c_device_id *id)
 {
@@ -95,7 +171,11 @@ static int bq27xxx_battery_i2c_probe(struct i2c_client *client,
 	di->dev = &client->dev;
 	di->chip = id->driver_data;
 	di->name = name;
+
 	di->bus.read = bq27xxx_battery_i2c_read;
+	di->bus.write = bq27xxx_battery_i2c_write;
+	di->bus.read_bulk = bq27xxx_battery_i2c_bulk_read;
+	di->bus.write_bulk = bq27xxx_battery_i2c_bulk_write;
 
 	ret = bq27xxx_battery_setup(di);
 	if (ret)
-- 
2.9.3