linux/drivers/power/bq27x00_battery.c
Krzysztof Kozlowski 297d716f62 power_supply: Change ownership from driver to core
Change the ownership of power_supply structure from each driver
implementing the class to the power supply core.

The patch changes power_supply_register() function thus all drivers
implementing power supply class are adjusted.

Each driver provides the implementation of power supply. However it
should not be the owner of power supply class instance because it is
exposed by core to other subsystems with power_supply_get_by_name().
These other subsystems have no knowledge when the driver will unregister
the power supply. This leads to several issues when driver is unbound -
mostly because user of power supply accesses freed memory.

Instead let the core own the instance of struct 'power_supply'.  Other
users of this power supply will still access valid memory because it
will be freed when device reference count reaches 0. Currently this
means "it will leak" but power_supply_put() call in next patches will
solve it.

This solves invalid memory references in following race condition
scenario:

Thread 1: charger manager
Thread 2: power supply driver, used by charger manager

THREAD 1 (charger manager)         THREAD 2 (power supply driver)
==========================         ==============================
psy = power_supply_get_by_name()
                                   Driver unbind, .remove
                                     power_supply_unregister()
                                     Device fully removed
psy->get_property()

The 'get_property' call is executed in invalid context because the driver was
unbound and struct 'power_supply' memory was freed.

This could be observed easily with charger manager driver (here compiled
with max17040 fuel gauge):

$ cat /sys/devices/virtual/power_supply/cm-battery/capacity &
$ echo "1-0036" > /sys/bus/i2c/drivers/max17040/unbind
[   55.725123] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[   55.732584] pgd = d98d4000
[   55.734060] [00000000] *pgd=5afa2831, *pte=00000000, *ppte=00000000
[   55.740318] Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM
[   55.746210] Modules linked in:
[   55.749259] CPU: 1 PID: 2936 Comm: cat Tainted: G        W       3.19.0-rc1-next-20141226-00048-gf79f475f3c44-dirty #1496
[   55.760190] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[   55.766270] task: d9b76f00 ti: daf54000 task.ti: daf54000
[   55.771647] PC is at 0x0
[   55.774182] LR is at charger_get_property+0x2f4/0x36c
[   55.779201] pc : [<00000000>]    lr : [<c034b0b4>]    psr: 60000013
[   55.779201] sp : daf55e90  ip : 00000003  fp : 00000000
[   55.790657] r10: 00000000  r9 : c06e2878  r8 : d9b26c68
[   55.795865] r7 : dad81610  r6 : daec7410  r5 : daf55ebc  r4 : 00000000
[   55.802367] r3 : 00000000  r2 : daf55ebc  r1 : 0000002a  r0 : d9b26c68
[   55.808879] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
[   55.815994] Control: 10c5387d  Table: 598d406a  DAC: 00000015
[   55.821723] Process cat (pid: 2936, stack limit = 0xdaf54210)
[   55.827451] Stack: (0xdaf55e90 to 0xdaf56000)
[   55.831795] 5e80:                                     60000013 c01459c4 0000002a c06f8ef8
[   55.839956] 5ea0: db651000 c06f8ef8 daebac00 c04cb668 daebac08 c0346864 00000000 c01459c4
[   55.848115] 5ec0: d99eaa80 c06f8ef8 00000fff 00001000 db651000 c027f25c c027f240 d99eaa80
[   55.856274] 5ee0: d9a06c00 c0146218 daf55f18 00001000 d99eaa80 db4c18c0 00000001 00000001
[   55.864468] 5f00: daf55f80 c0144c78 c0144c54 c0107f90 00015000 d99eaab0 00000000 00000000
[   55.872603] 5f20: 000051c7 00000000 db4c18c0 c04a9370 00015000 00001000 daf55f80 00001000
[   55.880763] 5f40: daf54000 00015000 00000000 c00e53dc db4c18c0 c00e548c 0000000d 00008124
[   55.888937] 5f60: 00000001 00000000 00000000 db4c18c0 db4c18c0 00001000 00015000 c00e5550
[   55.897099] 5f80: 00000000 00000000 00001000 00001000 00015000 00000003 00000003 c000f364
[   55.905239] 5fa0: 00000000 c000f1a0 00001000 00015000 00000003 00015000 00001000 0001333c
[   55.913399] 5fc0: 00001000 00015000 00000003 00000003 00000002 00000000 00000000 00000000
[   55.921560] 5fe0: 7fffe000 be999850 0000a225 b6f3c19c 60000010 00000003 00000000 00000000
[   55.929744] [<c034b0b4>] (charger_get_property) from [<c0346864>] (power_supply_show_property+0x48/0x20c)
[   55.939286] [<c0346864>] (power_supply_show_property) from [<c027f25c>] (dev_attr_show+0x1c/0x48)
[   55.948130] [<c027f25c>] (dev_attr_show) from [<c0146218>] (sysfs_kf_seq_show+0x84/0x104)
[   55.956298] [<c0146218>] (sysfs_kf_seq_show) from [<c0144c78>] (kernfs_seq_show+0x24/0x28)
[   55.964536] [<c0144c78>] (kernfs_seq_show) from [<c0107f90>] (seq_read+0x1b0/0x484)
[   55.972172] [<c0107f90>] (seq_read) from [<c00e53dc>] (__vfs_read+0x18/0x4c)
[   55.979188] [<c00e53dc>] (__vfs_read) from [<c00e548c>] (vfs_read+0x7c/0x100)
[   55.986304] [<c00e548c>] (vfs_read) from [<c00e5550>] (SyS_read+0x40/0x8c)
[   55.993164] [<c00e5550>] (SyS_read) from [<c000f1a0>] (ret_fast_syscall+0x0/0x48)
[   56.000626] Code: bad PC value
[   56.011652] ---[ end trace 7b64343fbdae8ef1 ]---

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

[for the nvec part]
Reviewed-by: Marc Dietrich <marvin24@gmx.de>

[for compal-laptop.c]
Acked-by: Darren Hart <dvhart@linux.intel.com>

[for the mfd part]
Acked-by: Lee Jones <lee.jones@linaro.org>

[for the hid part]
Acked-by: Jiri Kosina <jkosina@suse.cz>

[for the acpi part]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Signed-off-by: Sebastian Reichel <sre@kernel.org>
2015-03-13 23:15:51 +01:00

1115 lines
27 KiB
C

/*
* 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
* http://www.ti.com/product/BQ27742-G1
* http://www.ti.com/product/BQ27510-G3
*/
#include <linux/device.h>
#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)
#define BQ27742_POWER_AVG 0x76
#define BQ27510_REG_SOC 0x20
#define BQ27510_REG_DCAP 0x2E /* Design capacity */
#define BQ27510_REG_CYCT 0x1E /* Cycle count total */
/* bq27425 register addresses are same as bq27x00 addresses minus 4 */
#define BQ27425_REG_OFFSET 0x04
#define BQ27425_REG_SOC (0x1C + BQ27425_REG_OFFSET)
#define BQ27425_REG_DCAP (0x3C + BQ27425_REG_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, BQ27742, BQ27510};
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 enum power_supply_property bq27742_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_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,
POWER_SUPPLY_PROP_HEALTH,
};
static enum power_supply_property bq27510_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_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,
POWER_SUPPLY_PROP_HEALTH,
};
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 || di->chip == BQ27742
|| di->chip == BQ27510)
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 || di->chip == BQ27742)
rsoc = bq27x00_read(di, BQ27500_REG_SOC, false);
else if (di->chip == BQ27510)
rsoc = bq27x00_read(di, BQ27510_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)
{
int flags;
bool is_bq27500 = di->chip == BQ27500;
bool is_bq27742 = di->chip == BQ27742;
bool is_higher = bq27xxx_is_chip_version_higher(di);
bool flags_1b = !(is_bq27500 || is_bq27742);
flags = bq27x00_read(di, BQ27x00_REG_FLAGS, flags_1b);
if (flags >= 0 && !is_higher && (flags & BQ27000_FLAG_CI))
return -ENODATA;
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)) {
if (di->chip == BQ27425)
ilmd = bq27x00_read(di, BQ27425_REG_DCAP, false);
else if (di->chip == BQ27510)
ilmd = bq27x00_read(di, BQ27510_REG_DCAP, false);
else
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 Kelvin
* 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 = 5 * temp / 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;
if (di->chip == BQ27510)
cyct = bq27x00_read(di, BQ27510_REG_CYCT, false);
else
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 (di->chip == BQ27510) {
if (tval & BQ27500_FLAG_OTC)
return POWER_SUPPLY_HEALTH_OVERHEAT;
return POWER_SUPPLY_HEALTH_GOOD;
} 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_bq27510 = di->chip == BQ27510;
bool is_bq27425 = di->chip == BQ27425;
bool is_bq27742 = di->chip == BQ27742;
bool flags_1b = !(is_bq27500 || is_bq27742);
cache.flags = bq27x00_read(di, BQ27x00_REG_FLAGS, flags_1b);
if ((cache.flags & 0xff) == 0xff)
/* read error */
cache.flags = -1;
if (cache.flags >= 0) {
if (!is_bq27500 && !is_bq27425 && !is_bq27742 && !is_bq27510
&& (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_bq27742 || is_bq27510)
cache.time_to_empty =
bq27x00_battery_read_time(di,
BQ27x00_REG_TTE);
else 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);
if (is_bq27742)
cache.power_avg =
bq27x00_battery_read_pwr_avg(di,
BQ27742_POWER_AVG);
else
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 (di->cache.capacity != cache.capacity)
power_supply_changed(di->bat);
if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
di->cache = cache;
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;
}
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 = power_supply_get_drvdata(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);
if (ret == 0)
val->intval -= 2731;
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 = power_supply_get_drvdata(psy);
cancel_delayed_work_sync(&di->work);
schedule_delayed_work(&di->work, 0);
}
static int bq27x00_powersupply_init(struct bq27x00_device_info *di,
const char *name)
{
int ret;
struct power_supply_desc *psy_desc;
struct power_supply_config psy_cfg = { .drv_data = di, };
psy_desc = devm_kzalloc(di->dev, sizeof(*psy_desc), GFP_KERNEL);
if (!psy_desc)
return -ENOMEM;
psy_desc->name = name;
psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
if (di->chip == BQ27425) {
psy_desc->properties = bq27425_battery_props;
psy_desc->num_properties = ARRAY_SIZE(bq27425_battery_props);
} else if (di->chip == BQ27742) {
psy_desc->properties = bq27742_battery_props;
psy_desc->num_properties = ARRAY_SIZE(bq27742_battery_props);
} else if (di->chip == BQ27510) {
psy_desc->properties = bq27510_battery_props;
psy_desc->num_properties = ARRAY_SIZE(bq27510_battery_props);
} else {
psy_desc->properties = bq27x00_battery_props;
psy_desc->num_properties = ARRAY_SIZE(bq27x00_battery_props);
}
psy_desc->get_property = bq27x00_battery_get_property;
psy_desc->external_power_changed = bq27x00_external_power_changed;
INIT_DELAYED_WORK(&di->work, bq27x00_battery_poll);
mutex_init(&di->lock);
di->bat = power_supply_register_no_ws(di->dev, psy_desc, &psy_cfg);
if (IS_ERR(di->bat)) {
ret = PTR_ERR(di->bat);
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 */
mutex_lock(&battery_mutex);
num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
mutex_unlock(&battery_mutex);
if (num < 0)
return num;
name = devm_kasprintf(&client->dev, GFP_KERNEL, "%s-%d", id->name, num);
if (!name) {
dev_err(&client->dev, "failed to allocate device name\n");
retval = -ENOMEM;
goto batt_failed;
}
di = devm_kzalloc(&client->dev, sizeof(*di), GFP_KERNEL);
if (!di) {
dev_err(&client->dev, "failed to allocate device info data\n");
retval = -ENOMEM;
goto batt_failed;
}
di->id = num;
di->dev = &client->dev;
di->chip = id->driver_data;
di->bus.read = &bq27x00_read_i2c;
retval = bq27x00_powersupply_init(di, name);
if (retval)
goto batt_failed;
i2c_set_clientdata(client, di);
return 0;
batt_failed:
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);
mutex_lock(&battery_mutex);
idr_remove(&battery_id, di->id);
mutex_unlock(&battery_mutex);
return 0;
}
static const struct i2c_device_id bq27x00_id[] = {
{ "bq27200", BQ27000 }, /* bq27200 is same as bq27000, but with i2c */
{ "bq27500", BQ27500 },
{ "bq27425", BQ27425 },
{ "bq27742", BQ27742 },
{ "bq27510", BQ27510 },
{},
};
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 bq27000_battery_probe(struct platform_device *pdev)
{
struct bq27x00_device_info *di;
struct bq27000_platform_data *pdata = pdev->dev.platform_data;
const char *name;
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 = devm_kzalloc(&pdev->dev, 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;
name = pdata->name ?: dev_name(&pdev->dev);
di->bus.read = &bq27000_read_platform;
return bq27x00_powersupply_init(di, name);
}
static int bq27000_battery_remove(struct platform_device *pdev)
{
struct bq27x00_device_info *di = platform_get_drvdata(pdev);
bq27x00_powersupply_unregister(di);
return 0;
}
static struct platform_driver bq27000_battery_driver = {
.probe = bq27000_battery_probe,
.remove = bq27000_battery_remove,
.driver = {
.name = "bq27000-battery",
},
};
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");