2 * BQ27x00 battery driver
4 * Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
5 * Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
6 * Copyright (C) 2010-2011 Lars-Peter Clausen <lars@metafoo.de>
8 * Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
10 * This package is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
14 * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
16 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22 * http://focus.ti.com/docs/prod/folders/print/bq27000.html
23 * http://focus.ti.com/docs/prod/folders/print/bq27500.html
26 #include <linux/module.h>
27 #include <linux/param.h>
28 #include <linux/jiffies.h>
29 #include <linux/workqueue.h>
30 #include <linux/delay.h>
31 #include <linux/platform_device.h>
32 #include <linux/power_supply.h>
33 #include <linux/idr.h>
34 #include <linux/i2c.h>
35 #include <linux/slab.h>
36 #include <asm/unaligned.h>
38 #include <linux/power/bq27x00_battery.h>
40 #define DRIVER_VERSION "1.2.0"
42 #define BQ27x00_REG_TEMP 0x06
43 #define BQ27x00_REG_VOLT 0x08
44 #define BQ27x00_REG_AI 0x14
45 #define BQ27x00_REG_FLAGS 0x0A
46 #define BQ27x00_REG_TTE 0x16
47 #define BQ27x00_REG_TTF 0x18
48 #define BQ27x00_REG_TTECP 0x26
49 #define BQ27x00_REG_NAC 0x0C /* Nominal available capaciy */
50 #define BQ27x00_REG_LMD 0x12 /* Last measured discharge */
51 #define BQ27x00_REG_CYCT 0x2A /* Cycle count total */
52 #define BQ27x00_REG_AE 0x22 /* Available enery */
54 #define BQ27000_REG_RSOC 0x0B /* Relative State-of-Charge */
55 #define BQ27000_REG_ILMD 0x76 /* Initial last measured discharge */
56 #define BQ27000_FLAG_CHGS BIT(7)
57 #define BQ27000_FLAG_FC BIT(5)
59 #define BQ27500_REG_SOC 0x2C
60 #define BQ27500_REG_DCAP 0x3C /* Design capacity */
61 #define BQ27500_FLAG_DSC BIT(0)
62 #define BQ27500_FLAG_FC BIT(9)
64 #define BQ27000_RS 20 /* Resistor sense */
66 struct bq27x00_device_info
;
67 struct bq27x00_access_methods
{
68 int (*read
)(struct bq27x00_device_info
*di
, u8 reg
, bool single
);
71 enum bq27x00_chip
{ BQ27000
, BQ27500
};
73 struct bq27x00_reg_cache
{
76 int time_to_empty_avg
;
86 struct bq27x00_device_info
{
89 enum bq27x00_chip chip
;
91 struct bq27x00_reg_cache cache
;
92 int charge_design_full
;
94 unsigned long last_update
;
95 struct delayed_work work
;
97 struct power_supply bat
;
99 struct bq27x00_access_methods bus
;
104 static enum power_supply_property bq27x00_battery_props
[] = {
105 POWER_SUPPLY_PROP_STATUS
,
106 POWER_SUPPLY_PROP_PRESENT
,
107 POWER_SUPPLY_PROP_VOLTAGE_NOW
,
108 POWER_SUPPLY_PROP_CURRENT_NOW
,
109 POWER_SUPPLY_PROP_CAPACITY
,
110 POWER_SUPPLY_PROP_TEMP
,
111 POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW
,
112 POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG
,
113 POWER_SUPPLY_PROP_TIME_TO_FULL_NOW
,
114 POWER_SUPPLY_PROP_TECHNOLOGY
,
115 POWER_SUPPLY_PROP_CHARGE_FULL
,
116 POWER_SUPPLY_PROP_CHARGE_NOW
,
117 POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN
,
118 POWER_SUPPLY_PROP_CHARGE_COUNTER
,
119 POWER_SUPPLY_PROP_ENERGY_NOW
,
122 static unsigned int poll_interval
= 360;
123 module_param(poll_interval
, uint
, 0644);
124 MODULE_PARM_DESC(poll_interval
, "battery poll interval in seconds - " \
125 "0 disables polling");
128 * Common code for BQ27x00 devices
131 static inline int bq27x00_read(struct bq27x00_device_info
*di
, u8 reg
,
134 return di
->bus
.read(di
, reg
, single
);
138 * Return the battery Relative State-of-Charge
139 * Or < 0 if something fails.
141 static int bq27x00_battery_read_rsoc(struct bq27x00_device_info
*di
)
145 if (di
->chip
== BQ27500
)
146 rsoc
= bq27x00_read(di
, BQ27500_REG_SOC
, false);
148 rsoc
= bq27x00_read(di
, BQ27000_REG_RSOC
, true);
151 dev_err(di
->dev
, "error reading relative State-of-Charge\n");
157 * Return a battery charge value in µAh
158 * Or < 0 if something fails.
160 static int bq27x00_battery_read_charge(struct bq27x00_device_info
*di
, u8 reg
)
164 charge
= bq27x00_read(di
, reg
, false);
166 dev_err(di
->dev
, "error reading nominal available capacity\n");
170 if (di
->chip
== BQ27500
)
173 charge
= charge
* 3570 / BQ27000_RS
;
179 * Return the battery Nominal available capaciy in µAh
180 * Or < 0 if something fails.
182 static inline int bq27x00_battery_read_nac(struct bq27x00_device_info
*di
)
184 return bq27x00_battery_read_charge(di
, BQ27x00_REG_NAC
);
188 * Return the battery Last measured discharge in µAh
189 * Or < 0 if something fails.
191 static inline int bq27x00_battery_read_lmd(struct bq27x00_device_info
*di
)
193 return bq27x00_battery_read_charge(di
, BQ27x00_REG_LMD
);
197 * Return the battery Initial last measured discharge in µAh
198 * Or < 0 if something fails.
200 static int bq27x00_battery_read_ilmd(struct bq27x00_device_info
*di
)
204 if (di
->chip
== BQ27500
)
205 ilmd
= bq27x00_read(di
, BQ27500_REG_DCAP
, false);
207 ilmd
= bq27x00_read(di
, BQ27000_REG_ILMD
, true);
210 dev_err(di
->dev
, "error reading initial last measured discharge\n");
214 if (di
->chip
== BQ27500
)
217 ilmd
= ilmd
* 256 * 3570 / BQ27000_RS
;
223 * Return the battery Cycle count total
224 * Or < 0 if something fails.
226 static int bq27x00_battery_read_cyct(struct bq27x00_device_info
*di
)
230 cyct
= bq27x00_read(di
, BQ27x00_REG_CYCT
, false);
232 dev_err(di
->dev
, "error reading cycle count total\n");
238 * Read a time register.
239 * Return < 0 if something fails.
241 static int bq27x00_battery_read_time(struct bq27x00_device_info
*di
, u8 reg
)
245 tval
= bq27x00_read(di
, reg
, false);
247 dev_err(di
->dev
, "error reading register %02x: %d\n", reg
, tval
);
257 static void bq27x00_update(struct bq27x00_device_info
*di
)
259 struct bq27x00_reg_cache cache
= {0, };
260 bool is_bq27500
= di
->chip
== BQ27500
;
262 cache
.flags
= bq27x00_read(di
, BQ27x00_REG_FLAGS
, is_bq27500
);
263 if (cache
.flags
>= 0) {
264 cache
.capacity
= bq27x00_battery_read_rsoc(di
);
265 cache
.temperature
= bq27x00_read(di
, BQ27x00_REG_TEMP
, false);
266 cache
.time_to_empty
= bq27x00_battery_read_time(di
, BQ27x00_REG_TTE
);
267 cache
.time_to_empty_avg
= bq27x00_battery_read_time(di
, BQ27x00_REG_TTECP
);
268 cache
.time_to_full
= bq27x00_battery_read_time(di
, BQ27x00_REG_TTF
);
269 cache
.charge_full
= bq27x00_battery_read_lmd(di
);
270 cache
.charge_counter
= bq27x00_battery_read_cyct(di
);
273 cache
.current_now
= bq27x00_read(di
, BQ27x00_REG_AI
, false);
275 /* We only have to read charge design full once */
276 if (di
->charge_design_full
<= 0)
277 di
->charge_design_full
= bq27x00_battery_read_ilmd(di
);
280 /* Ignore current_now which is a snapshot of the current battery state
281 * and is likely to be different even between two consecutive reads */
282 if (memcmp(&di
->cache
, &cache
, sizeof(cache
) - sizeof(int)) != 0) {
284 power_supply_changed(&di
->bat
);
287 di
->last_update
= jiffies
;
290 static void bq27x00_battery_poll(struct work_struct
*work
)
292 struct bq27x00_device_info
*di
=
293 container_of(work
, struct bq27x00_device_info
, work
.work
);
297 if (poll_interval
> 0) {
298 /* The timer does not have to be accurate. */
299 set_timer_slack(&di
->work
.timer
, poll_interval
* HZ
/ 4);
300 schedule_delayed_work(&di
->work
, poll_interval
* HZ
);
306 * Return the battery temperature in tenths of degree Celsius
307 * Or < 0 if something fails.
309 static int bq27x00_battery_temperature(struct bq27x00_device_info
*di
,
310 union power_supply_propval
*val
)
312 if (di
->cache
.temperature
< 0)
313 return di
->cache
.temperature
;
315 if (di
->chip
== BQ27500
)
316 val
->intval
= di
->cache
.temperature
- 2731;
318 val
->intval
= ((di
->cache
.temperature
* 5) - 5463) / 2;
324 * Return the battery average current in µA
325 * Note that current can be negative signed as well
326 * Or 0 if something fails.
328 static int bq27x00_battery_current(struct bq27x00_device_info
*di
,
329 union power_supply_propval
*val
)
333 if (di
->chip
== BQ27500
)
334 curr
= bq27x00_read(di
, BQ27x00_REG_AI
, false);
336 curr
= di
->cache
.current_now
;
341 if (di
->chip
== BQ27500
) {
342 /* bq27500 returns signed value */
343 val
->intval
= (int)((s16
)curr
) * 1000;
345 if (di
->cache
.flags
& BQ27000_FLAG_CHGS
) {
346 dev_dbg(di
->dev
, "negative current!\n");
350 val
->intval
= curr
* 3570 / BQ27000_RS
;
356 static int bq27x00_battery_status(struct bq27x00_device_info
*di
,
357 union power_supply_propval
*val
)
361 if (di
->chip
== BQ27500
) {
362 if (di
->cache
.flags
& BQ27500_FLAG_FC
)
363 status
= POWER_SUPPLY_STATUS_FULL
;
364 else if (di
->cache
.flags
& BQ27500_FLAG_DSC
)
365 status
= POWER_SUPPLY_STATUS_DISCHARGING
;
367 status
= POWER_SUPPLY_STATUS_CHARGING
;
369 if (di
->cache
.flags
& BQ27000_FLAG_FC
)
370 status
= POWER_SUPPLY_STATUS_FULL
;
371 else if (di
->cache
.flags
& BQ27000_FLAG_CHGS
)
372 status
= POWER_SUPPLY_STATUS_CHARGING
;
373 else if (power_supply_am_i_supplied(&di
->bat
))
374 status
= POWER_SUPPLY_STATUS_NOT_CHARGING
;
376 status
= POWER_SUPPLY_STATUS_DISCHARGING
;
379 val
->intval
= status
;
385 * Return the battery Voltage in milivolts
386 * Or < 0 if something fails.
388 static int bq27x00_battery_voltage(struct bq27x00_device_info
*di
,
389 union power_supply_propval
*val
)
393 volt
= bq27x00_read(di
, BQ27x00_REG_VOLT
, false);
397 val
->intval
= volt
* 1000;
403 * Return the battery Available energy in µWh
404 * Or < 0 if something fails.
406 static int bq27x00_battery_energy(struct bq27x00_device_info
*di
,
407 union power_supply_propval
*val
)
411 ae
= bq27x00_read(di
, BQ27x00_REG_AE
, false);
413 dev_err(di
->dev
, "error reading available energy\n");
417 if (di
->chip
== BQ27500
)
420 ae
= ae
* 29200 / BQ27000_RS
;
428 static int bq27x00_simple_value(int value
,
429 union power_supply_propval
*val
)
439 #define to_bq27x00_device_info(x) container_of((x), \
440 struct bq27x00_device_info, bat);
442 static int bq27x00_battery_get_property(struct power_supply
*psy
,
443 enum power_supply_property psp
,
444 union power_supply_propval
*val
)
447 struct bq27x00_device_info
*di
= to_bq27x00_device_info(psy
);
449 mutex_lock(&di
->lock
);
450 if (time_is_before_jiffies(di
->last_update
+ 5 * HZ
)) {
451 cancel_delayed_work_sync(&di
->work
);
452 bq27x00_battery_poll(&di
->work
.work
);
454 mutex_unlock(&di
->lock
);
456 if (psp
!= POWER_SUPPLY_PROP_PRESENT
&& di
->cache
.flags
< 0)
460 case POWER_SUPPLY_PROP_STATUS
:
461 ret
= bq27x00_battery_status(di
, val
);
463 case POWER_SUPPLY_PROP_VOLTAGE_NOW
:
464 ret
= bq27x00_battery_voltage(di
, val
);
466 case POWER_SUPPLY_PROP_PRESENT
:
467 val
->intval
= di
->cache
.flags
< 0 ? 0 : 1;
469 case POWER_SUPPLY_PROP_CURRENT_NOW
:
470 ret
= bq27x00_battery_current(di
, val
);
472 case POWER_SUPPLY_PROP_CAPACITY
:
473 ret
= bq27x00_simple_value(di
->cache
.capacity
, val
);
475 case POWER_SUPPLY_PROP_TEMP
:
476 ret
= bq27x00_battery_temperature(di
, val
);
478 case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW
:
479 ret
= bq27x00_simple_value(di
->cache
.time_to_empty
, val
);
481 case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG
:
482 ret
= bq27x00_simple_value(di
->cache
.time_to_empty_avg
, val
);
484 case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW
:
485 ret
= bq27x00_simple_value(di
->cache
.time_to_full
, val
);
487 case POWER_SUPPLY_PROP_TECHNOLOGY
:
488 val
->intval
= POWER_SUPPLY_TECHNOLOGY_LION
;
490 case POWER_SUPPLY_PROP_CHARGE_NOW
:
491 ret
= bq27x00_simple_value(bq27x00_battery_read_nac(di
), val
);
493 case POWER_SUPPLY_PROP_CHARGE_FULL
:
494 ret
= bq27x00_simple_value(di
->cache
.charge_full
, val
);
496 case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN
:
497 ret
= bq27x00_simple_value(di
->charge_design_full
, val
);
499 case POWER_SUPPLY_PROP_CHARGE_COUNTER
:
500 ret
= bq27x00_simple_value(di
->cache
.charge_counter
, val
);
502 case POWER_SUPPLY_PROP_ENERGY_NOW
:
503 ret
= bq27x00_battery_energy(di
, val
);
512 static void bq27x00_external_power_changed(struct power_supply
*psy
)
514 struct bq27x00_device_info
*di
= to_bq27x00_device_info(psy
);
516 cancel_delayed_work_sync(&di
->work
);
517 schedule_delayed_work(&di
->work
, 0);
520 static int bq27x00_powersupply_init(struct bq27x00_device_info
*di
)
524 di
->bat
.type
= POWER_SUPPLY_TYPE_BATTERY
;
525 di
->bat
.properties
= bq27x00_battery_props
;
526 di
->bat
.num_properties
= ARRAY_SIZE(bq27x00_battery_props
);
527 di
->bat
.get_property
= bq27x00_battery_get_property
;
528 di
->bat
.external_power_changed
= bq27x00_external_power_changed
;
530 INIT_DELAYED_WORK(&di
->work
, bq27x00_battery_poll
);
531 mutex_init(&di
->lock
);
533 ret
= power_supply_register(di
->dev
, &di
->bat
);
535 dev_err(di
->dev
, "failed to register battery: %d\n", ret
);
539 dev_info(di
->dev
, "support ver. %s enabled\n", DRIVER_VERSION
);
546 static void bq27x00_powersupply_unregister(struct bq27x00_device_info
*di
)
548 cancel_delayed_work_sync(&di
->work
);
550 power_supply_unregister(&di
->bat
);
552 mutex_destroy(&di
->lock
);
556 /* i2c specific code */
557 #ifdef CONFIG_BATTERY_BQ27X00_I2C
559 /* If the system has several batteries we need a different name for each
562 static DEFINE_IDR(battery_id
);
563 static DEFINE_MUTEX(battery_mutex
);
565 static int bq27x00_read_i2c(struct bq27x00_device_info
*di
, u8 reg
, bool single
)
567 struct i2c_client
*client
= to_i2c_client(di
->dev
);
568 struct i2c_msg msg
[2];
569 unsigned char data
[2];
572 if (!client
->adapter
)
575 msg
[0].addr
= client
->addr
;
578 msg
[0].len
= sizeof(reg
);
579 msg
[1].addr
= client
->addr
;
580 msg
[1].flags
= I2C_M_RD
;
587 ret
= i2c_transfer(client
->adapter
, msg
, ARRAY_SIZE(msg
));
592 ret
= get_unaligned_le16(data
);
599 static int bq27x00_battery_probe(struct i2c_client
*client
,
600 const struct i2c_device_id
*id
)
603 struct bq27x00_device_info
*di
;
607 /* Get new ID for the new battery device */
608 retval
= idr_pre_get(&battery_id
, GFP_KERNEL
);
611 mutex_lock(&battery_mutex
);
612 retval
= idr_get_new(&battery_id
, client
, &num
);
613 mutex_unlock(&battery_mutex
);
617 name
= kasprintf(GFP_KERNEL
, "%s-%d", id
->name
, num
);
619 dev_err(&client
->dev
, "failed to allocate device name\n");
624 di
= kzalloc(sizeof(*di
), GFP_KERNEL
);
626 dev_err(&client
->dev
, "failed to allocate device info data\n");
632 di
->dev
= &client
->dev
;
633 di
->chip
= id
->driver_data
;
635 di
->bus
.read
= &bq27x00_read_i2c
;
637 if (bq27x00_powersupply_init(di
))
640 i2c_set_clientdata(client
, di
);
649 mutex_lock(&battery_mutex
);
650 idr_remove(&battery_id
, num
);
651 mutex_unlock(&battery_mutex
);
656 static int bq27x00_battery_remove(struct i2c_client
*client
)
658 struct bq27x00_device_info
*di
= i2c_get_clientdata(client
);
660 bq27x00_powersupply_unregister(di
);
664 mutex_lock(&battery_mutex
);
665 idr_remove(&battery_id
, di
->id
);
666 mutex_unlock(&battery_mutex
);
673 static const struct i2c_device_id bq27x00_id
[] = {
674 { "bq27200", BQ27000
}, /* bq27200 is same as bq27000, but with i2c */
675 { "bq27500", BQ27500
},
678 MODULE_DEVICE_TABLE(i2c
, bq27x00_id
);
680 static struct i2c_driver bq27x00_battery_driver
= {
682 .name
= "bq27x00-battery",
684 .probe
= bq27x00_battery_probe
,
685 .remove
= bq27x00_battery_remove
,
686 .id_table
= bq27x00_id
,
689 static inline int bq27x00_battery_i2c_init(void)
691 int ret
= i2c_add_driver(&bq27x00_battery_driver
);
693 printk(KERN_ERR
"Unable to register BQ27x00 i2c driver\n");
698 static inline void bq27x00_battery_i2c_exit(void)
700 i2c_del_driver(&bq27x00_battery_driver
);
705 static inline int bq27x00_battery_i2c_init(void) { return 0; }
706 static inline void bq27x00_battery_i2c_exit(void) {};
710 /* platform specific code */
711 #ifdef CONFIG_BATTERY_BQ27X00_PLATFORM
713 static int bq27000_read_platform(struct bq27x00_device_info
*di
, u8 reg
,
716 struct device
*dev
= di
->dev
;
717 struct bq27000_platform_data
*pdata
= dev
->platform_data
;
718 unsigned int timeout
= 3;
723 /* Make sure the value has not changed in between reading the
724 * lower and the upper part */
725 upper
= pdata
->read(dev
, reg
+ 1);
731 lower
= pdata
->read(dev
, reg
);
735 upper
= pdata
->read(dev
, reg
+ 1);
736 } while (temp
!= upper
&& --timeout
);
741 return (upper
<< 8) | lower
;
744 return pdata
->read(dev
, reg
);
747 static int __devinit
bq27000_battery_probe(struct platform_device
*pdev
)
749 struct bq27x00_device_info
*di
;
750 struct bq27000_platform_data
*pdata
= pdev
->dev
.platform_data
;
754 dev_err(&pdev
->dev
, "no platform_data supplied\n");
759 dev_err(&pdev
->dev
, "no hdq read callback supplied\n");
763 di
= kzalloc(sizeof(*di
), GFP_KERNEL
);
765 dev_err(&pdev
->dev
, "failed to allocate device info data\n");
769 platform_set_drvdata(pdev
, di
);
771 di
->dev
= &pdev
->dev
;
774 di
->bat
.name
= pdata
->name
?: dev_name(&pdev
->dev
);
775 di
->bus
.read
= &bq27000_read_platform
;
777 ret
= bq27x00_powersupply_init(di
);
784 platform_set_drvdata(pdev
, NULL
);
790 static int __devexit
bq27000_battery_remove(struct platform_device
*pdev
)
792 struct bq27x00_device_info
*di
= platform_get_drvdata(pdev
);
794 bq27x00_powersupply_unregister(di
);
796 platform_set_drvdata(pdev
, NULL
);
802 static struct platform_driver bq27000_battery_driver
= {
803 .probe
= bq27000_battery_probe
,
804 .remove
= __devexit_p(bq27000_battery_remove
),
806 .name
= "bq27000-battery",
807 .owner
= THIS_MODULE
,
811 static inline int bq27x00_battery_platform_init(void)
813 int ret
= platform_driver_register(&bq27000_battery_driver
);
815 printk(KERN_ERR
"Unable to register BQ27000 platform driver\n");
820 static inline void bq27x00_battery_platform_exit(void)
822 platform_driver_unregister(&bq27000_battery_driver
);
827 static inline int bq27x00_battery_platform_init(void) { return 0; }
828 static inline void bq27x00_battery_platform_exit(void) {};
836 static int __init
bq27x00_battery_init(void)
840 ret
= bq27x00_battery_i2c_init();
844 ret
= bq27x00_battery_platform_init();
846 bq27x00_battery_i2c_exit();
850 module_init(bq27x00_battery_init
);
852 static void __exit
bq27x00_battery_exit(void)
854 bq27x00_battery_platform_exit();
855 bq27x00_battery_i2c_exit();
857 module_exit(bq27x00_battery_exit
);
859 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
860 MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
861 MODULE_LICENSE("GPL");