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linux/drivers/power/bq27x00_battery.c
Julia Lawall f77609959a bq27x00_battery: Fix error return code 
Initialize return variable before exiting on an error path.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}

// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
2012-08-22 18:48:13 -07:00

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/*
* BQ27x00 battery driver
*
* Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
* Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
* Copyright (C) 2010-2011 Lars-Peter Clausen <lars@metafoo.de>
* Copyright (C) 2011 Pali Rohár <pali.rohar@gmail.com>
*
* Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
*
* This package is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
*/
/*
* Datasheets:
* http://focus.ti.com/docs/prod/folders/print/bq27000.html
* http://focus.ti.com/docs/prod/folders/print/bq27500.html
* http://www.ti.com/product/bq27425-g1
*/
#include <linux/module.h>
#include <linux/param.h>
#include <linux/jiffies.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/idr.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <asm/unaligned.h>
#include <linux/power/bq27x00_battery.h>
#define DRIVER_VERSION "1.2.0"
#define BQ27x00_REG_TEMP 0x06
#define BQ27x00_REG_VOLT 0x08
#define BQ27x00_REG_AI 0x14
#define BQ27x00_REG_FLAGS 0x0A
#define BQ27x00_REG_TTE 0x16
#define BQ27x00_REG_TTF 0x18
#define BQ27x00_REG_TTECP 0x26
#define BQ27x00_REG_NAC 0x0C /* Nominal available capacity */
#define BQ27x00_REG_LMD 0x12 /* Last measured discharge */
#define BQ27x00_REG_CYCT 0x2A /* Cycle count total */
#define BQ27x00_REG_AE 0x22 /* Available energy */
#define BQ27x00_POWER_AVG 0x24
#define BQ27000_REG_RSOC 0x0B /* Relative State-of-Charge */
#define BQ27000_REG_ILMD 0x76 /* Initial last measured discharge */
#define BQ27000_FLAG_EDVF BIT(0) /* Final End-of-Discharge-Voltage flag */
#define BQ27000_FLAG_EDV1 BIT(1) /* First End-of-Discharge-Voltage flag */
#define BQ27000_FLAG_CI BIT(4) /* Capacity Inaccurate flag */
#define BQ27000_FLAG_FC BIT(5)
#define BQ27000_FLAG_CHGS BIT(7) /* Charge state flag */
#define BQ27500_REG_SOC 0x2C
#define BQ27500_REG_DCAP 0x3C /* Design capacity */
#define BQ27500_FLAG_DSC BIT(0)
#define BQ27500_FLAG_SOCF BIT(1) /* State-of-Charge threshold final */
#define BQ27500_FLAG_SOC1 BIT(2) /* State-of-Charge threshold 1 */
#define BQ27500_FLAG_FC BIT(9)
#define BQ27500_FLAG_OTC BIT(15)
/* bq27425 register addresses are same as bq27x00 addresses minus 4 */
#define BQ27425_REG_OFFSET 0x04
#define BQ27425_REG_SOC 0x18 /* Register address plus offset */
#define BQ27000_RS 20 /* Resistor sense */
#define BQ27x00_POWER_CONSTANT (256 * 29200 / 1000)
struct bq27x00_device_info;
struct bq27x00_access_methods {
int (*read)(struct bq27x00_device_info *di, u8 reg, bool single);
};
enum bq27x00_chip { BQ27000, BQ27500, BQ27425};
struct bq27x00_reg_cache {
int temperature;
int time_to_empty;
int time_to_empty_avg;
int time_to_full;
int charge_full;
int cycle_count;
int capacity;
int energy;
int flags;
int power_avg;
int health;
};
struct bq27x00_device_info {
struct device *dev;
int id;
enum bq27x00_chip chip;
struct bq27x00_reg_cache cache;
int charge_design_full;
unsigned long last_update;
struct delayed_work work;
struct power_supply bat;
struct bq27x00_access_methods bus;
struct mutex lock;
};
static enum power_supply_property bq27x00_battery_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_PRESENT,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
POWER_SUPPLY_PROP_CURRENT_NOW,
POWER_SUPPLY_PROP_CAPACITY,
POWER_SUPPLY_PROP_CAPACITY_LEVEL,
POWER_SUPPLY_PROP_TEMP,
POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
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,
POWER_SUPPLY_PROP_POWER_AVG,
POWER_SUPPLY_PROP_HEALTH,
};
static enum power_supply_property bq27425_battery_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_PRESENT,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
POWER_SUPPLY_PROP_CURRENT_NOW,
POWER_SUPPLY_PROP_CAPACITY,
POWER_SUPPLY_PROP_CAPACITY_LEVEL,
POWER_SUPPLY_PROP_TEMP,
POWER_SUPPLY_PROP_TECHNOLOGY,
POWER_SUPPLY_PROP_CHARGE_FULL,
POWER_SUPPLY_PROP_CHARGE_NOW,
POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
};
static unsigned int poll_interval = 360;
module_param(poll_interval, uint, 0644);
MODULE_PARM_DESC(poll_interval, "battery poll interval in seconds - " \
"0 disables polling");
/*
* Common code for BQ27x00 devices
*/
static inline int bq27x00_read(struct bq27x00_device_info *di, u8 reg,
bool single)
{
if (di->chip == BQ27425)
return di->bus.read(di, reg - BQ27425_REG_OFFSET, single);
return di->bus.read(di, reg, single);
}
/*
* Higher versions of the chip like BQ27425 and BQ27500
* differ from BQ27000 and BQ27200 in calculation of certain
* parameters. Hence we need to check for the chip type.
*/
static bool bq27xxx_is_chip_version_higher(struct bq27x00_device_info *di)
{
if (di->chip == BQ27425 || di->chip == BQ27500)
return true;
return false;
}
/*
* Return the battery Relative State-of-Charge
* Or < 0 if something fails.
*/
static int bq27x00_battery_read_rsoc(struct bq27x00_device_info *di)
{
int rsoc;
if (di->chip == BQ27500)
rsoc = bq27x00_read(di, BQ27500_REG_SOC, false);
else if (di->chip == BQ27425)
rsoc = bq27x00_read(di, BQ27425_REG_SOC, false);
else
rsoc = bq27x00_read(di, BQ27000_REG_RSOC, true);
if (rsoc < 0)
dev_dbg(di->dev, "error reading relative State-of-Charge\n");
return rsoc;
}
/*
* Return a battery charge value in µAh
* Or < 0 if something fails.
*/
static int bq27x00_battery_read_charge(struct bq27x00_device_info *di, u8 reg)
{
int charge;
charge = bq27x00_read(di, reg, false);
if (charge < 0) {
dev_dbg(di->dev, "error reading charge register %02x: %d\n",
reg, charge);
return charge;
}
if (bq27xxx_is_chip_version_higher(di))
charge *= 1000;
else
charge = charge * 3570 / BQ27000_RS;
return charge;
}
/*
* Return the battery Nominal available capaciy in µAh
* Or < 0 if something fails.
*/
static inline int bq27x00_battery_read_nac(struct bq27x00_device_info *di)
{
return bq27x00_battery_read_charge(di, BQ27x00_REG_NAC);
}
/*
* Return the battery Last measured discharge in µAh
* Or < 0 if something fails.
*/
static inline int bq27x00_battery_read_lmd(struct bq27x00_device_info *di)
{
return bq27x00_battery_read_charge(di, BQ27x00_REG_LMD);
}
/*
* Return the battery Initial last measured discharge in µAh
* Or < 0 if something fails.
*/
static int bq27x00_battery_read_ilmd(struct bq27x00_device_info *di)
{
int ilmd;
if (bq27xxx_is_chip_version_higher(di))
ilmd = bq27x00_read(di, BQ27500_REG_DCAP, false);
else
ilmd = bq27x00_read(di, BQ27000_REG_ILMD, true);
if (ilmd < 0) {
dev_dbg(di->dev, "error reading initial last measured discharge\n");
return ilmd;
}
if (bq27xxx_is_chip_version_higher(di))
ilmd *= 1000;
else
ilmd = ilmd * 256 * 3570 / BQ27000_RS;
return ilmd;
}
/*
* Return the battery Available energy in µWh
* Or < 0 if something fails.
*/
static int bq27x00_battery_read_energy(struct bq27x00_device_info *di)
{
int ae;
ae = bq27x00_read(di, BQ27x00_REG_AE, false);
if (ae < 0) {
dev_dbg(di->dev, "error reading available energy\n");
return ae;
}
if (di->chip == BQ27500)
ae *= 1000;
else
ae = ae * 29200 / BQ27000_RS;
return ae;
}
/*
* Return the battery temperature in tenths of degree Celsius
* Or < 0 if something fails.
*/
static int bq27x00_battery_read_temperature(struct bq27x00_device_info *di)
{
int temp;
temp = bq27x00_read(di, BQ27x00_REG_TEMP, false);
if (temp < 0) {
dev_err(di->dev, "error reading temperature\n");
return temp;
}
if (bq27xxx_is_chip_version_higher(di))
temp -= 2731;
else
temp = ((temp * 5) - 5463) / 2;
return temp;
}
/*
* Return the battery Cycle count total
* Or < 0 if something fails.
*/
static int bq27x00_battery_read_cyct(struct bq27x00_device_info *di)
{
int cyct;
cyct = bq27x00_read(di, BQ27x00_REG_CYCT, false);
if (cyct < 0)
dev_err(di->dev, "error reading cycle count total\n");
return cyct;
}
/*
* Read a time register.
* Return < 0 if something fails.
*/
static int bq27x00_battery_read_time(struct bq27x00_device_info *di, u8 reg)
{
int tval;
tval = bq27x00_read(di, reg, false);
if (tval < 0) {
dev_dbg(di->dev, "error reading time register %02x: %d\n",
reg, tval);
return tval;
}
if (tval == 65535)
return -ENODATA;
return tval * 60;
}
/*
* Read a power avg register.
* Return < 0 if something fails.
*/
static int bq27x00_battery_read_pwr_avg(struct bq27x00_device_info *di, u8 reg)
{
int tval;
tval = bq27x00_read(di, reg, false);
if (tval < 0) {
dev_err(di->dev, "error reading power avg rgister %02x: %d\n",
reg, tval);
return tval;
}
if (di->chip == BQ27500)
return tval;
else
return (tval * BQ27x00_POWER_CONSTANT) / BQ27000_RS;
}
/*
* Read flag register.
* Return < 0 if something fails.
*/
static int bq27x00_battery_read_health(struct bq27x00_device_info *di)
{
int tval;
tval = bq27x00_read(di, BQ27x00_REG_FLAGS, false);
if (tval < 0) {
dev_err(di->dev, "error reading flag register:%d\n", tval);
return tval;
}
if ((di->chip == BQ27500)) {
if (tval & BQ27500_FLAG_SOCF)
tval = POWER_SUPPLY_HEALTH_DEAD;
else if (tval & BQ27500_FLAG_OTC)
tval = POWER_SUPPLY_HEALTH_OVERHEAT;
else
tval = POWER_SUPPLY_HEALTH_GOOD;
return tval;
} else {
if (tval & BQ27000_FLAG_EDV1)
tval = POWER_SUPPLY_HEALTH_DEAD;
else
tval = POWER_SUPPLY_HEALTH_GOOD;
return tval;
}
return -1;
}
static void bq27x00_update(struct bq27x00_device_info *di)
{
struct bq27x00_reg_cache cache = {0, };
bool is_bq27500 = di->chip == BQ27500;
bool is_bq27425 = di->chip == BQ27425;
cache.flags = bq27x00_read(di, BQ27x00_REG_FLAGS, !is_bq27500);
if (cache.flags >= 0) {
if (!is_bq27500 && !is_bq27425
&& (cache.flags & BQ27000_FLAG_CI)) {
dev_info(di->dev, "battery is not calibrated! ignoring capacity values\n");
cache.capacity = -ENODATA;
cache.energy = -ENODATA;
cache.time_to_empty = -ENODATA;
cache.time_to_empty_avg = -ENODATA;
cache.time_to_full = -ENODATA;
cache.charge_full = -ENODATA;
cache.health = -ENODATA;
} else {
cache.capacity = bq27x00_battery_read_rsoc(di);
if (!is_bq27425) {
cache.energy = bq27x00_battery_read_energy(di);
cache.time_to_empty =
bq27x00_battery_read_time(di,
BQ27x00_REG_TTE);
cache.time_to_empty_avg =
bq27x00_battery_read_time(di,
BQ27x00_REG_TTECP);
cache.time_to_full =
bq27x00_battery_read_time(di,
BQ27x00_REG_TTF);
}
cache.charge_full = bq27x00_battery_read_lmd(di);
cache.health = bq27x00_battery_read_health(di);
}
cache.temperature = bq27x00_battery_read_temperature(di);
if (!is_bq27425)
cache.cycle_count = bq27x00_battery_read_cyct(di);
cache.cycle_count = bq27x00_battery_read_cyct(di);
cache.power_avg =
bq27x00_battery_read_pwr_avg(di, BQ27x00_POWER_AVG);
/* We only have to read charge design full once */
if (di->charge_design_full <= 0)
di->charge_design_full = bq27x00_battery_read_ilmd(di);
}
if (memcmp(&di->cache, &cache, sizeof(cache)) != 0) {
di->cache = cache;
power_supply_changed(&di->bat);
}
di->last_update = jiffies;
}
static void bq27x00_battery_poll(struct work_struct *work)
{
struct bq27x00_device_info *di =
container_of(work, struct bq27x00_device_info, work.work);
bq27x00_update(di);
if (poll_interval > 0) {
/* The timer does not have to be accurate. */
set_timer_slack(&di->work.timer, poll_interval * HZ / 4);
schedule_delayed_work(&di->work, poll_interval * HZ);
}
}
/*
* Return the battery average current in µA
* Note that current can be negative signed as well
* Or 0 if something fails.
*/
static int bq27x00_battery_current(struct bq27x00_device_info *di,
union power_supply_propval *val)
{
int curr;
int flags;
curr = bq27x00_read(di, BQ27x00_REG_AI, false);
if (curr < 0) {
dev_err(di->dev, "error reading current\n");
return curr;
}
if (bq27xxx_is_chip_version_higher(di)) {
/* bq27500 returns signed value */
val->intval = (int)((s16)curr) * 1000;
} else {
flags = bq27x00_read(di, BQ27x00_REG_FLAGS, false);
if (flags & BQ27000_FLAG_CHGS) {
dev_dbg(di->dev, "negative current!\n");
curr = -curr;
}
val->intval = curr * 3570 / BQ27000_RS;
}
return 0;
}
static int bq27x00_battery_status(struct bq27x00_device_info *di,
union power_supply_propval *val)
{
int status;
if (bq27xxx_is_chip_version_higher(di)) {
if (di->cache.flags & BQ27500_FLAG_FC)
status = POWER_SUPPLY_STATUS_FULL;
else if (di->cache.flags & BQ27500_FLAG_DSC)
status = POWER_SUPPLY_STATUS_DISCHARGING;
else
status = POWER_SUPPLY_STATUS_CHARGING;
} else {
if (di->cache.flags & BQ27000_FLAG_FC)
status = POWER_SUPPLY_STATUS_FULL;
else if (di->cache.flags & BQ27000_FLAG_CHGS)
status = POWER_SUPPLY_STATUS_CHARGING;
else if (power_supply_am_i_supplied(&di->bat))
status = POWER_SUPPLY_STATUS_NOT_CHARGING;
else
status = POWER_SUPPLY_STATUS_DISCHARGING;
}
val->intval = status;
return 0;
}
static int bq27x00_battery_capacity_level(struct bq27x00_device_info *di,
union power_supply_propval *val)
{
int level;
if (bq27xxx_is_chip_version_higher(di)) {
if (di->cache.flags & BQ27500_FLAG_FC)
level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
else if (di->cache.flags & BQ27500_FLAG_SOC1)
level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
else if (di->cache.flags & BQ27500_FLAG_SOCF)
level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
else
level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
} else {
if (di->cache.flags & BQ27000_FLAG_FC)
level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
else if (di->cache.flags & BQ27000_FLAG_EDV1)
level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
else if (di->cache.flags & BQ27000_FLAG_EDVF)
level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
else
level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
}
val->intval = level;
return 0;
}
/*
* Return the battery Voltage in millivolts
* Or < 0 if something fails.
*/
static int bq27x00_battery_voltage(struct bq27x00_device_info *di,
union power_supply_propval *val)
{
int volt;
volt = bq27x00_read(di, BQ27x00_REG_VOLT, false);
if (volt < 0) {
dev_err(di->dev, "error reading voltage\n");
return volt;
}
val->intval = volt * 1000;
return 0;
}
static int bq27x00_simple_value(int value,
union power_supply_propval *val)
{
if (value < 0)
return value;
val->intval = value;
return 0;
}
#define to_bq27x00_device_info(x) container_of((x), \
struct bq27x00_device_info, bat);
static int bq27x00_battery_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
int ret = 0;
struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
mutex_lock(&di->lock);
if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
cancel_delayed_work_sync(&di->work);
bq27x00_battery_poll(&di->work.work);
}
mutex_unlock(&di->lock);
if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
return -ENODEV;
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
ret = bq27x00_battery_status(di, val);
break;
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
ret = bq27x00_battery_voltage(di, val);
break;
case POWER_SUPPLY_PROP_PRESENT:
val->intval = di->cache.flags < 0 ? 0 : 1;
break;
case POWER_SUPPLY_PROP_CURRENT_NOW:
ret = bq27x00_battery_current(di, val);
break;
case POWER_SUPPLY_PROP_CAPACITY:
ret = bq27x00_simple_value(di->cache.capacity, val);
break;
case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
ret = bq27x00_battery_capacity_level(di, val);
break;
case POWER_SUPPLY_PROP_TEMP:
ret = bq27x00_simple_value(di->cache.temperature, val);
break;
case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
ret = bq27x00_simple_value(di->cache.time_to_empty, val);
break;
case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
ret = bq27x00_simple_value(di->cache.time_to_empty_avg, val);
break;
case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
ret = bq27x00_simple_value(di->cache.time_to_full, val);
break;
case POWER_SUPPLY_PROP_TECHNOLOGY:
val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
break;
case POWER_SUPPLY_PROP_CHARGE_NOW:
ret = bq27x00_simple_value(bq27x00_battery_read_nac(di), val);
break;
case POWER_SUPPLY_PROP_CHARGE_FULL:
ret = bq27x00_simple_value(di->cache.charge_full, val);
break;
case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
ret = bq27x00_simple_value(di->charge_design_full, val);
break;
case POWER_SUPPLY_PROP_CYCLE_COUNT:
ret = bq27x00_simple_value(di->cache.cycle_count, val);
break;
case POWER_SUPPLY_PROP_ENERGY_NOW:
ret = bq27x00_simple_value(di->cache.energy, val);
break;
case POWER_SUPPLY_PROP_POWER_AVG:
ret = bq27x00_simple_value(di->cache.power_avg, val);
break;
case POWER_SUPPLY_PROP_HEALTH:
ret = bq27x00_simple_value(di->cache.health, val);
break;
default:
return -EINVAL;
}
return ret;
}
static void bq27x00_external_power_changed(struct power_supply *psy)
{
struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
cancel_delayed_work_sync(&di->work);
schedule_delayed_work(&di->work, 0);
}
static int bq27x00_powersupply_init(struct bq27x00_device_info *di)
{
int ret;
di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
di->chip = BQ27425;
if (di->chip == BQ27425) {
di->bat.properties = bq27425_battery_props;
di->bat.num_properties = ARRAY_SIZE(bq27425_battery_props);
} else {
di->bat.properties = bq27x00_battery_props;
di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props);
}
di->bat.get_property = bq27x00_battery_get_property;
di->bat.external_power_changed = bq27x00_external_power_changed;
INIT_DELAYED_WORK(&di->work, bq27x00_battery_poll);
mutex_init(&di->lock);
ret = power_supply_register(di->dev, &di->bat);
if (ret) {
dev_err(di->dev, "failed to register battery: %d\n", ret);
return ret;
}
dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
bq27x00_update(di);
return 0;
}
static void bq27x00_powersupply_unregister(struct bq27x00_device_info *di)
{
/*
* power_supply_unregister call bq27x00_battery_get_property which
* call bq27x00_battery_poll.
* Make sure that bq27x00_battery_poll will not call
* schedule_delayed_work again after unregister (which cause OOPS).
*/
poll_interval = 0;
cancel_delayed_work_sync(&di->work);
power_supply_unregister(&di->bat);
mutex_destroy(&di->lock);
}
/* i2c specific code */
#ifdef CONFIG_BATTERY_BQ27X00_I2C
/* If the system has several batteries we need a different name for each
* of them...
*/
static DEFINE_IDR(battery_id);
static DEFINE_MUTEX(battery_mutex);
static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, bool single)
{
struct i2c_client *client = to_i2c_client(di->dev);
struct i2c_msg msg[2];
unsigned char data[2];
int ret;
if (!client->adapter)
return -ENODEV;
msg[0].addr = client->addr;
msg[0].flags = 0;
msg[0].buf = &reg;
msg[0].len = sizeof(reg);
msg[1].addr = client->addr;
msg[1].flags = I2C_M_RD;
msg[1].buf = data;
if (single)
msg[1].len = 1;
else
msg[1].len = 2;
ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
if (ret < 0)
return ret;
if (!single)
ret = get_unaligned_le16(data);
else
ret = data[0];
return ret;
}
static int bq27x00_battery_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
char *name;
struct bq27x00_device_info *di;
int num;
int retval = 0;
/* Get new ID for the new battery device */
retval = idr_pre_get(&battery_id, GFP_KERNEL);
if (retval == 0)
return -ENOMEM;
mutex_lock(&battery_mutex);
retval = idr_get_new(&battery_id, client, &num);
mutex_unlock(&battery_mutex);
if (retval < 0)
return retval;
name = kasprintf(GFP_KERNEL, "%s-%d", id->name, num);
if (!name) {
dev_err(&client->dev, "failed to allocate device name\n");
retval = -ENOMEM;
goto batt_failed_1;
}
di = kzalloc(sizeof(*di), GFP_KERNEL);
if (!di) {
dev_err(&client->dev, "failed to allocate device info data\n");
retval = -ENOMEM;
goto batt_failed_2;
}
di->id = num;
di->dev = &client->dev;
di->chip = id->driver_data;
di->bat.name = name;
di->bus.read = &bq27x00_read_i2c;
retval = bq27x00_powersupply_init(di);
if (retval)
goto batt_failed_3;
i2c_set_clientdata(client, di);
return 0;
batt_failed_3:
kfree(di);
batt_failed_2:
kfree(name);
batt_failed_1:
mutex_lock(&battery_mutex);
idr_remove(&battery_id, num);
mutex_unlock(&battery_mutex);
return retval;
}
static int bq27x00_battery_remove(struct i2c_client *client)
{
struct bq27x00_device_info *di = i2c_get_clientdata(client);
bq27x00_powersupply_unregister(di);
kfree(di->bat.name);
mutex_lock(&battery_mutex);
idr_remove(&battery_id, di->id);
mutex_unlock(&battery_mutex);
kfree(di);
return 0;
}
static const struct i2c_device_id bq27x00_id[] = {
{ "bq27200", BQ27000 }, /* bq27200 is same as bq27000, but with i2c */
{ "bq27500", BQ27500 },
{ "bq27425", BQ27425 },
{},
};
MODULE_DEVICE_TABLE(i2c, bq27x00_id);
static struct i2c_driver bq27x00_battery_driver = {
.driver = {
.name = "bq27x00-battery",
},
.probe = bq27x00_battery_probe,
.remove = bq27x00_battery_remove,
.id_table = bq27x00_id,
};
static inline int bq27x00_battery_i2c_init(void)
{
int ret = i2c_add_driver(&bq27x00_battery_driver);
if (ret)
printk(KERN_ERR "Unable to register BQ27x00 i2c driver\n");
return ret;
}
static inline void bq27x00_battery_i2c_exit(void)
{
i2c_del_driver(&bq27x00_battery_driver);
}
#else
static inline int bq27x00_battery_i2c_init(void) { return 0; }
static inline void bq27x00_battery_i2c_exit(void) {};
#endif
/* platform specific code */
#ifdef CONFIG_BATTERY_BQ27X00_PLATFORM
static int bq27000_read_platform(struct bq27x00_device_info *di, u8 reg,
bool single)
{
struct device *dev = di->dev;
struct bq27000_platform_data *pdata = dev->platform_data;
unsigned int timeout = 3;
int upper, lower;
int temp;
if (!single) {
/* Make sure the value has not changed in between reading the
* lower and the upper part */
upper = pdata->read(dev, reg + 1);
do {
temp = upper;
if (upper < 0)
return upper;
lower = pdata->read(dev, reg);
if (lower < 0)
return lower;
upper = pdata->read(dev, reg + 1);
} while (temp != upper && --timeout);
if (timeout == 0)
return -EIO;
return (upper << 8) | lower;
}
return pdata->read(dev, reg);
}
static int __devinit bq27000_battery_probe(struct platform_device *pdev)
{
struct bq27x00_device_info *di;
struct bq27000_platform_data *pdata = pdev->dev.platform_data;
int ret;
if (!pdata) {
dev_err(&pdev->dev, "no platform_data supplied\n");
return -EINVAL;
}
if (!pdata->read) {
dev_err(&pdev->dev, "no hdq read callback supplied\n");
return -EINVAL;
}
di = kzalloc(sizeof(*di), GFP_KERNEL);
if (!di) {
dev_err(&pdev->dev, "failed to allocate device info data\n");
return -ENOMEM;
}
platform_set_drvdata(pdev, di);
di->dev = &pdev->dev;
di->chip = BQ27000;
di->bat.name = pdata->name ?: dev_name(&pdev->dev);
di->bus.read = &bq27000_read_platform;
ret = bq27x00_powersupply_init(di);
if (ret)
goto err_free;
return 0;
err_free:
platform_set_drvdata(pdev, NULL);
kfree(di);
return ret;
}
static int __devexit bq27000_battery_remove(struct platform_device *pdev)
{
struct bq27x00_device_info *di = platform_get_drvdata(pdev);
bq27x00_powersupply_unregister(di);
platform_set_drvdata(pdev, NULL);
kfree(di);
return 0;
}
static struct platform_driver bq27000_battery_driver = {
.probe = bq27000_battery_probe,
.remove = __devexit_p(bq27000_battery_remove),
.driver = {
.name = "bq27000-battery",
.owner = THIS_MODULE,
},
};
static inline int bq27x00_battery_platform_init(void)
{
int ret = platform_driver_register(&bq27000_battery_driver);
if (ret)
printk(KERN_ERR "Unable to register BQ27000 platform driver\n");
return ret;
}
static inline void bq27x00_battery_platform_exit(void)
{
platform_driver_unregister(&bq27000_battery_driver);
}
#else
static inline int bq27x00_battery_platform_init(void) { return 0; }
static inline void bq27x00_battery_platform_exit(void) {};
#endif
/*
* Module stuff
*/
static int __init bq27x00_battery_init(void)
{
int ret;
ret = bq27x00_battery_i2c_init();
if (ret)
return ret;
ret = bq27x00_battery_platform_init();
if (ret)
bq27x00_battery_i2c_exit();
return ret;
}
module_init(bq27x00_battery_init);
static void __exit bq27x00_battery_exit(void)
{
bq27x00_battery_platform_exit();
bq27x00_battery_i2c_exit();
}
module_exit(bq27x00_battery_exit);
MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
MODULE_LICENSE("GPL");
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