bq27441: Driver in kernel

Used to be an out-of-tree module

arch/arm/configs/zero-gravitas_defconfig

@@ -146,6 +146,8 @@ CONFIG_SPI=y
 CONFIG_GPIO_SYSFS=y
 CONFIG_POWER_SUPPLY=y
 CONFIG_BATTERY_BQ27XXX=y
+CONFIG_BATTERY_BQ27XXX_I2C=y
+CONFIG_BATTERY_BQ27441_ZEROGRAVITAS=y
 CONFIG_CHARGER_GPIO=y
 CONFIG_POWER_RESET=y
 CONFIG_POWER_RESET_SYSCON=y

drivers/power/supply/Kconfig

@@ -178,6 +178,14 @@ config BATTERY_BQ27XXX_I2C
 	  Say Y here to enable support for batteries with BQ27xxx chips
 	  connected over an I2C bus.
 
+config BATTERY_BQ27441_ZEROGRAVITAS
+	tristate "BQ27441 support for zero-gravitas"
+	depends on BATTERY_BQ27XXX_I2C
+	default n
+	help
+	  Say Y here to enable support for the bq27441 fuel gauge driver
+	  for zero-gravitas
+
 config BATTERY_DA9030
 	tristate "DA9030 battery driver"
 	depends on PMIC_DA903X

drivers/power/supply/Makefile

@@ -33,6 +33,7 @@ obj-$(CONFIG_BATTERY_WM97XX)	+= wm97xx_battery.o
 obj-$(CONFIG_BATTERY_SBS)	+= sbs-battery.o
 obj-$(CONFIG_BATTERY_BQ27XXX)	+= bq27xxx_battery.o
 obj-$(CONFIG_BATTERY_BQ27XXX_I2C) += bq27xxx_battery_i2c.o
+obj-$(CONFIG_BATTERY_BQ27441_ZEROGRAVITAS) += bq27441_battery.o
 obj-$(CONFIG_BATTERY_DA9030)	+= da9030_battery.o
 obj-$(CONFIG_BATTERY_DA9052)	+= da9052-battery.o
 obj-$(CONFIG_CHARGER_DA9150)	+= da9150-charger.o

drivers/power/supply/bq27xxx_battery.c

@@ -51,6 +51,10 @@
 
 #include <linux/power/bq27xxx_battery.h>
 
+#ifdef CONFIG_BATTERY_BQ27441_ZEROGRAVITAS
+#include <linux/power/bq27441_battery.h>
+#endif
+
 #define DRIVER_VERSION		"1.2.0"
 
 #define BQ27XXX_MANUFACTURER	"Texas Instruments"
@@ -1037,6 +1041,10 @@ int bq27xxx_battery_setup(struct bq27xxx_device_info *di)
 
 	dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
 
+#ifdef CONFIG_BATTERY_BQ27441_ZEROGRAVITAS
+	bq27441_init(di);
+#endif
+
 	bq27xxx_battery_update(di);
 
 	mutex_lock(&bq27xxx_list_lock);
@@ -1141,6 +1149,10 @@ static int bq27xxx_battery_platform_remove(struct platform_device *pdev)
 {
 	struct bq27xxx_device_info *di = platform_get_drvdata(pdev);
 
+#ifdef CONFIG_BATTERY_BQ27441_ZEROGRAVITAS
+	bq27441_exit(di);
+#endif
+
 	bq27xxx_battery_teardown(di);
 
 	return 0;

drivers/power/supply/bq27xxx_battery_i2c.c

@@ -18,6 +18,8 @@
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <asm/unaligned.h>
+#include <linux/slab.h>
+#include <linux/string.h>
 
 #include <linux/power/bq27xxx_battery.h>
 
@@ -33,6 +35,31 @@ static irqreturn_t bq27xxx_battery_irq_handler_thread(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+static int bq27xxx_battery_i2c_write(struct bq27xxx_device_info *di, u8 reg,
+				    const u8 *data, size_t len)
+{
+	struct i2c_client *client = to_i2c_client(di->dev);
+	int ret;
+	unsigned char *buf;
+
+	if (!client->adapter)
+		return -ENODEV;
+
+	buf = kzalloc(len + sizeof(reg), GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	buf[0] = reg;
+	memcpy (&buf[1], data, len);
+
+	ret = i2c_master_send(client, buf, len + sizeof(reg));
+
+	kfree(buf);
+
+	return ret;
+}
+
+
 static int bq27xxx_battery_i2c_read(struct bq27xxx_device_info *di, u8 reg,
 				    bool single)
 {
@@ -96,6 +123,7 @@ static int bq27xxx_battery_i2c_probe(struct i2c_client *client,
 	di->chip = id->driver_data;
 	di->name = name;
 	di->bus.read = bq27xxx_battery_i2c_read;
+	di->bus.write = bq27xxx_battery_i2c_write;
 
 	ret = bq27xxx_battery_setup(di);
 	if (ret)

include/linux/power/bq27441_battery.h

@@ -0,0 +1,7 @@
+#ifndef _BQ27441_BATTERY_H
+#define _BQ27441_BATTERY_H
+
+int bq27441_init(struct bq27xxx_device_info *di);
+int bq27441_exit(struct bq27xxx_device_info *di);
+
+#endif /* _BQ27441_BATTERY_H */

include/linux/power/bq27xxx_battery.h

@@ -32,6 +32,7 @@ struct bq27xxx_platform_data {
 struct bq27xxx_device_info;
 struct bq27xxx_access_methods {
 	int (*read)(struct bq27xxx_device_info *di, u8 reg, bool single);
+	int (*write)(struct bq27xxx_device_info *di, u8 reg, const u8 *data, size_t len);
 };
 
 struct bq27xxx_reg_cache {
@@ -48,6 +49,8 @@ struct bq27xxx_reg_cache {
 	int health;
 };
 
+struct dentry;
+
 struct bq27xxx_device_info {
 	struct device *dev;
 	int id;
@@ -62,6 +65,7 @@ struct bq27xxx_device_info {
 	struct list_head list;
 	struct mutex lock;
 	u8 *regs;
+	struct dentry *dfs_dir;
 };
 
 void bq27xxx_battery_update(struct bq27xxx_device_info *di);