2 * 1-wire client/driver for the Maxim/Dallas DS2781 Stand-Alone Fuel Gauge IC
4 * Author: Renata Sayakhova <renata@oktetlabs.ru>
6 * Based on ds2780_battery drivers
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/param.h>
18 #include <linux/platform_device.h>
19 #include <linux/power_supply.h>
20 #include <linux/idr.h>
23 #include "../w1/slaves/w1_ds2781.h"
25 /* Current unit measurement in uA for a 1 milli-ohm sense resistor */
26 #define DS2781_CURRENT_UNITS 1563
27 /* Charge unit measurement in uAh for a 1 milli-ohm sense resistor */
28 #define DS2781_CHARGE_UNITS 6250
29 /* Number of bytes in user EEPROM space */
30 #define DS2781_USER_EEPROM_SIZE (DS2781_EEPROM_BLOCK0_END - \
31 DS2781_EEPROM_BLOCK0_START + 1)
32 /* Number of bytes in parameter EEPROM space */
33 #define DS2781_PARAM_EEPROM_SIZE (DS2781_EEPROM_BLOCK1_END - \
34 DS2781_EEPROM_BLOCK1_START + 1)
36 struct ds2781_device_info
{
38 struct power_supply bat
;
39 struct device
*w1_dev
;
47 static const char model
[] = "DS2781";
48 static const char manufacturer
[] = "Maxim/Dallas";
50 static inline struct ds2781_device_info
*
51 to_ds2781_device_info(struct power_supply
*psy
)
53 return container_of(psy
, struct ds2781_device_info
, bat
);
56 static inline struct power_supply
*to_power_supply(struct device
*dev
)
58 return dev_get_drvdata(dev
);
61 static inline int ds2781_battery_io(struct ds2781_device_info
*dev_info
,
62 char *buf
, int addr
, size_t count
, int io
)
64 return w1_ds2781_io(dev_info
->w1_dev
, buf
, addr
, count
, io
);
67 static int w1_ds2781_read(struct ds2781_device_info
*dev_info
, char *buf
,
68 int addr
, size_t count
)
70 return ds2781_battery_io(dev_info
, buf
, addr
, count
, 0);
73 static inline int ds2781_read8(struct ds2781_device_info
*dev_info
, u8
*val
,
76 return ds2781_battery_io(dev_info
, val
, addr
, sizeof(u8
), 0);
79 static int ds2781_read16(struct ds2781_device_info
*dev_info
, s16
*val
,
85 ret
= ds2781_battery_io(dev_info
, raw
, addr
, sizeof(raw
), 0);
89 *val
= (raw
[0] << 8) | raw
[1];
94 static inline int ds2781_read_block(struct ds2781_device_info
*dev_info
,
95 u8
*val
, int addr
, size_t count
)
97 return ds2781_battery_io(dev_info
, val
, addr
, count
, 0);
100 static inline int ds2781_write(struct ds2781_device_info
*dev_info
, u8
*val
,
101 int addr
, size_t count
)
103 return ds2781_battery_io(dev_info
, val
, addr
, count
, 1);
106 static inline int ds2781_store_eeprom(struct device
*dev
, int addr
)
108 return w1_ds2781_eeprom_cmd(dev
, addr
, W1_DS2781_COPY_DATA
);
111 static inline int ds2781_recall_eeprom(struct device
*dev
, int addr
)
113 return w1_ds2781_eeprom_cmd(dev
, addr
, W1_DS2781_RECALL_DATA
);
116 static int ds2781_save_eeprom(struct ds2781_device_info
*dev_info
, int reg
)
120 ret
= ds2781_store_eeprom(dev_info
->w1_dev
, reg
);
124 ret
= ds2781_recall_eeprom(dev_info
->w1_dev
, reg
);
131 /* Set sense resistor value in mhos */
132 static int ds2781_set_sense_register(struct ds2781_device_info
*dev_info
,
137 ret
= ds2781_write(dev_info
, &conductance
,
138 DS2781_RSNSP
, sizeof(u8
));
142 return ds2781_save_eeprom(dev_info
, DS2781_RSNSP
);
145 /* Get RSGAIN value from 0 to 1.999 in steps of 0.001 */
146 static int ds2781_get_rsgain_register(struct ds2781_device_info
*dev_info
,
149 return ds2781_read16(dev_info
, rsgain
, DS2781_RSGAIN_MSB
);
152 /* Set RSGAIN value from 0 to 1.999 in steps of 0.001 */
153 static int ds2781_set_rsgain_register(struct ds2781_device_info
*dev_info
,
157 u8 raw
[] = {rsgain
>> 8, rsgain
& 0xFF};
159 ret
= ds2781_write(dev_info
, raw
,
160 DS2781_RSGAIN_MSB
, sizeof(raw
));
164 return ds2781_save_eeprom(dev_info
, DS2781_RSGAIN_MSB
);
167 static int ds2781_get_voltage(struct ds2781_device_info
*dev_info
,
174 ret
= w1_ds2781_read(dev_info
, val
, DS2781_VOLT_MSB
, 2 * sizeof(u8
));
178 * The voltage value is located in 10 bits across the voltage MSB
179 * and LSB registers in two's compliment form
180 * Sign bit of the voltage value is in bit 7 of the voltage MSB register
181 * Bits 9 - 3 of the voltage value are in bits 6 - 0 of the
182 * voltage MSB register
183 * Bits 2 - 0 of the voltage value are in bits 7 - 5 of the
184 * voltage LSB register
186 voltage_raw
= (val
[0] << 3) |
189 /* DS2781 reports voltage in units of 9.76mV, but the battery class
190 * reports in units of uV, so convert by multiplying by 9760. */
191 *voltage_uV
= voltage_raw
* 9760;
196 static int ds2781_get_temperature(struct ds2781_device_info
*dev_info
,
203 ret
= w1_ds2781_read(dev_info
, val
, DS2781_TEMP_MSB
, 2 * sizeof(u8
));
207 * The temperature value is located in 10 bits across the temperature
208 * MSB and LSB registers in two's compliment form
209 * Sign bit of the temperature value is in bit 7 of the temperature
211 * Bits 9 - 3 of the temperature value are in bits 6 - 0 of the
212 * temperature MSB register
213 * Bits 2 - 0 of the temperature value are in bits 7 - 5 of the
214 * temperature LSB register
216 temp_raw
= ((val
[0]) << 3) |
218 *temp
= temp_raw
+ (temp_raw
/ 4);
223 static int ds2781_get_current(struct ds2781_device_info
*dev_info
,
224 enum current_types type
, int *current_uA
)
228 u8 sense_res_raw
, reg_msb
;
231 * The units of measurement for current are dependent on the value of
232 * the sense resistor.
234 ret
= ds2781_read8(dev_info
, &sense_res_raw
, DS2781_RSNSP
);
238 if (sense_res_raw
== 0) {
239 dev_err(dev_info
->dev
, "sense resistor value is 0\n");
242 sense_res
= 1000 / sense_res_raw
;
244 if (type
== CURRENT_NOW
)
245 reg_msb
= DS2781_CURRENT_MSB
;
246 else if (type
== CURRENT_AVG
)
247 reg_msb
= DS2781_IAVG_MSB
;
252 * The current value is located in 16 bits across the current MSB
253 * and LSB registers in two's compliment form
254 * Sign bit of the current value is in bit 7 of the current MSB register
255 * Bits 14 - 8 of the current value are in bits 6 - 0 of the current
257 * Bits 7 - 0 of the current value are in bits 7 - 0 of the current
260 ret
= ds2781_read16(dev_info
, ¤t_raw
, reg_msb
);
264 *current_uA
= current_raw
* (DS2781_CURRENT_UNITS
/ sense_res
);
268 static int ds2781_get_accumulated_current(struct ds2781_device_info
*dev_info
,
269 int *accumulated_current
)
276 * The units of measurement for accumulated current are dependent on
277 * the value of the sense resistor.
279 ret
= ds2781_read8(dev_info
, &sense_res_raw
, DS2781_RSNSP
);
283 if (sense_res_raw
== 0) {
284 dev_err(dev_info
->dev
, "sense resistor value is 0\n");
287 sense_res
= 1000 / sense_res_raw
;
290 * The ACR value is located in 16 bits across the ACR MSB and
292 * Bits 15 - 8 of the ACR value are in bits 7 - 0 of the ACR
294 * Bits 7 - 0 of the ACR value are in bits 7 - 0 of the ACR
297 ret
= ds2781_read16(dev_info
, ¤t_raw
, DS2781_ACR_MSB
);
301 *accumulated_current
= current_raw
* (DS2781_CHARGE_UNITS
/ sense_res
);
305 static int ds2781_get_capacity(struct ds2781_device_info
*dev_info
,
311 ret
= ds2781_read8(dev_info
, &raw
, DS2781_RARC
);
319 static int ds2781_get_status(struct ds2781_device_info
*dev_info
, int *status
)
321 int ret
, current_uA
, capacity
;
323 ret
= ds2781_get_current(dev_info
, CURRENT_NOW
, ¤t_uA
);
327 ret
= ds2781_get_capacity(dev_info
, &capacity
);
331 if (power_supply_am_i_supplied(&dev_info
->bat
)) {
333 *status
= POWER_SUPPLY_STATUS_FULL
;
334 else if (current_uA
> 50000)
335 *status
= POWER_SUPPLY_STATUS_CHARGING
;
337 *status
= POWER_SUPPLY_STATUS_NOT_CHARGING
;
339 *status
= POWER_SUPPLY_STATUS_DISCHARGING
;
344 static int ds2781_get_charge_now(struct ds2781_device_info
*dev_info
,
351 * The RAAC value is located in 16 bits across the RAAC MSB and
353 * Bits 15 - 8 of the RAAC value are in bits 7 - 0 of the RAAC
355 * Bits 7 - 0 of the RAAC value are in bits 7 - 0 of the RAAC
358 ret
= ds2781_read16(dev_info
, &charge_raw
, DS2781_RAAC_MSB
);
362 *charge_now
= charge_raw
* 1600;
366 static int ds2781_get_control_register(struct ds2781_device_info
*dev_info
,
369 return ds2781_read8(dev_info
, control_reg
, DS2781_CONTROL
);
372 static int ds2781_set_control_register(struct ds2781_device_info
*dev_info
,
377 ret
= ds2781_write(dev_info
, &control_reg
,
378 DS2781_CONTROL
, sizeof(u8
));
382 return ds2781_save_eeprom(dev_info
, DS2781_CONTROL
);
385 static int ds2781_battery_get_property(struct power_supply
*psy
,
386 enum power_supply_property psp
,
387 union power_supply_propval
*val
)
390 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
393 case POWER_SUPPLY_PROP_VOLTAGE_NOW
:
394 ret
= ds2781_get_voltage(dev_info
, &val
->intval
);
397 case POWER_SUPPLY_PROP_TEMP
:
398 ret
= ds2781_get_temperature(dev_info
, &val
->intval
);
401 case POWER_SUPPLY_PROP_MODEL_NAME
:
405 case POWER_SUPPLY_PROP_MANUFACTURER
:
406 val
->strval
= manufacturer
;
409 case POWER_SUPPLY_PROP_CURRENT_NOW
:
410 ret
= ds2781_get_current(dev_info
, CURRENT_NOW
, &val
->intval
);
413 case POWER_SUPPLY_PROP_CURRENT_AVG
:
414 ret
= ds2781_get_current(dev_info
, CURRENT_AVG
, &val
->intval
);
417 case POWER_SUPPLY_PROP_STATUS
:
418 ret
= ds2781_get_status(dev_info
, &val
->intval
);
421 case POWER_SUPPLY_PROP_CAPACITY
:
422 ret
= ds2781_get_capacity(dev_info
, &val
->intval
);
425 case POWER_SUPPLY_PROP_CHARGE_COUNTER
:
426 ret
= ds2781_get_accumulated_current(dev_info
, &val
->intval
);
429 case POWER_SUPPLY_PROP_CHARGE_NOW
:
430 ret
= ds2781_get_charge_now(dev_info
, &val
->intval
);
440 static enum power_supply_property ds2781_battery_props
[] = {
441 POWER_SUPPLY_PROP_STATUS
,
442 POWER_SUPPLY_PROP_VOLTAGE_NOW
,
443 POWER_SUPPLY_PROP_TEMP
,
444 POWER_SUPPLY_PROP_MODEL_NAME
,
445 POWER_SUPPLY_PROP_MANUFACTURER
,
446 POWER_SUPPLY_PROP_CURRENT_NOW
,
447 POWER_SUPPLY_PROP_CURRENT_AVG
,
448 POWER_SUPPLY_PROP_CAPACITY
,
449 POWER_SUPPLY_PROP_CHARGE_COUNTER
,
450 POWER_SUPPLY_PROP_CHARGE_NOW
,
453 static ssize_t
ds2781_get_pmod_enabled(struct device
*dev
,
454 struct device_attribute
*attr
,
459 struct power_supply
*psy
= to_power_supply(dev
);
460 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
463 ret
= ds2781_get_control_register(dev_info
, &control_reg
);
467 return sprintf(buf
, "%d\n",
468 !!(control_reg
& DS2781_CONTROL_PMOD
));
471 static ssize_t
ds2781_set_pmod_enabled(struct device
*dev
,
472 struct device_attribute
*attr
,
477 u8 control_reg
, new_setting
;
478 struct power_supply
*psy
= to_power_supply(dev
);
479 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
482 ret
= ds2781_get_control_register(dev_info
, &control_reg
);
486 ret
= kstrtou8(buf
, 0, &new_setting
);
490 if ((new_setting
!= 0) && (new_setting
!= 1)) {
491 dev_err(dev_info
->dev
, "Invalid pmod setting (0 or 1)\n");
496 control_reg
|= DS2781_CONTROL_PMOD
;
498 control_reg
&= ~DS2781_CONTROL_PMOD
;
500 ret
= ds2781_set_control_register(dev_info
, control_reg
);
507 static ssize_t
ds2781_get_sense_resistor_value(struct device
*dev
,
508 struct device_attribute
*attr
,
513 struct power_supply
*psy
= to_power_supply(dev
);
514 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
516 ret
= ds2781_read8(dev_info
, &sense_resistor
, DS2781_RSNSP
);
520 ret
= sprintf(buf
, "%d\n", sense_resistor
);
524 static ssize_t
ds2781_set_sense_resistor_value(struct device
*dev
,
525 struct device_attribute
*attr
,
531 struct power_supply
*psy
= to_power_supply(dev
);
532 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
534 ret
= kstrtou8(buf
, 0, &new_setting
);
538 ret
= ds2781_set_sense_register(dev_info
, new_setting
);
545 static ssize_t
ds2781_get_rsgain_setting(struct device
*dev
,
546 struct device_attribute
*attr
,
551 struct power_supply
*psy
= to_power_supply(dev
);
552 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
554 ret
= ds2781_get_rsgain_register(dev_info
, &rsgain
);
558 return sprintf(buf
, "%d\n", rsgain
);
561 static ssize_t
ds2781_set_rsgain_setting(struct device
*dev
,
562 struct device_attribute
*attr
,
568 struct power_supply
*psy
= to_power_supply(dev
);
569 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
571 ret
= kstrtou16(buf
, 0, &new_setting
);
575 /* Gain can only be from 0 to 1.999 in steps of .001 */
576 if (new_setting
> 1999) {
577 dev_err(dev_info
->dev
, "Invalid rsgain setting (0 - 1999)\n");
581 ret
= ds2781_set_rsgain_register(dev_info
, new_setting
);
588 static ssize_t
ds2781_get_pio_pin(struct device
*dev
,
589 struct device_attribute
*attr
,
594 struct power_supply
*psy
= to_power_supply(dev
);
595 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
597 ret
= ds2781_read8(dev_info
, &sfr
, DS2781_SFR
);
601 ret
= sprintf(buf
, "%d\n", sfr
& DS2781_SFR_PIOSC
);
605 static ssize_t
ds2781_set_pio_pin(struct device
*dev
,
606 struct device_attribute
*attr
,
612 struct power_supply
*psy
= to_power_supply(dev
);
613 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
615 ret
= kstrtou8(buf
, 0, &new_setting
);
619 if ((new_setting
!= 0) && (new_setting
!= 1)) {
620 dev_err(dev_info
->dev
, "Invalid pio_pin setting (0 or 1)\n");
624 ret
= ds2781_write(dev_info
, &new_setting
,
625 DS2781_SFR
, sizeof(u8
));
632 static ssize_t
ds2781_read_param_eeprom_bin(struct file
*filp
,
633 struct kobject
*kobj
,
634 struct bin_attribute
*bin_attr
,
635 char *buf
, loff_t off
, size_t count
)
637 struct device
*dev
= container_of(kobj
, struct device
, kobj
);
638 struct power_supply
*psy
= to_power_supply(dev
);
639 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
641 count
= min_t(loff_t
, count
, DS2781_PARAM_EEPROM_SIZE
- off
);
643 return ds2781_read_block(dev_info
, buf
,
644 DS2781_EEPROM_BLOCK1_START
+ off
, count
);
647 static ssize_t
ds2781_write_param_eeprom_bin(struct file
*filp
,
648 struct kobject
*kobj
,
649 struct bin_attribute
*bin_attr
,
650 char *buf
, loff_t off
, size_t count
)
652 struct device
*dev
= container_of(kobj
, struct device
, kobj
);
653 struct power_supply
*psy
= to_power_supply(dev
);
654 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
657 count
= min_t(loff_t
, count
, DS2781_PARAM_EEPROM_SIZE
- off
);
659 ret
= ds2781_write(dev_info
, buf
,
660 DS2781_EEPROM_BLOCK1_START
+ off
, count
);
664 ret
= ds2781_save_eeprom(dev_info
, DS2781_EEPROM_BLOCK1_START
);
671 static struct bin_attribute ds2781_param_eeprom_bin_attr
= {
673 .name
= "param_eeprom",
674 .mode
= S_IRUGO
| S_IWUSR
,
676 .size
= DS2781_PARAM_EEPROM_SIZE
,
677 .read
= ds2781_read_param_eeprom_bin
,
678 .write
= ds2781_write_param_eeprom_bin
,
681 static ssize_t
ds2781_read_user_eeprom_bin(struct file
*filp
,
682 struct kobject
*kobj
,
683 struct bin_attribute
*bin_attr
,
684 char *buf
, loff_t off
, size_t count
)
686 struct device
*dev
= container_of(kobj
, struct device
, kobj
);
687 struct power_supply
*psy
= to_power_supply(dev
);
688 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
690 count
= min_t(loff_t
, count
, DS2781_USER_EEPROM_SIZE
- off
);
692 return ds2781_read_block(dev_info
, buf
,
693 DS2781_EEPROM_BLOCK0_START
+ off
, count
);
697 static ssize_t
ds2781_write_user_eeprom_bin(struct file
*filp
,
698 struct kobject
*kobj
,
699 struct bin_attribute
*bin_attr
,
700 char *buf
, loff_t off
, size_t count
)
702 struct device
*dev
= container_of(kobj
, struct device
, kobj
);
703 struct power_supply
*psy
= to_power_supply(dev
);
704 struct ds2781_device_info
*dev_info
= to_ds2781_device_info(psy
);
707 count
= min_t(loff_t
, count
, DS2781_USER_EEPROM_SIZE
- off
);
709 ret
= ds2781_write(dev_info
, buf
,
710 DS2781_EEPROM_BLOCK0_START
+ off
, count
);
714 ret
= ds2781_save_eeprom(dev_info
, DS2781_EEPROM_BLOCK0_START
);
721 static struct bin_attribute ds2781_user_eeprom_bin_attr
= {
723 .name
= "user_eeprom",
724 .mode
= S_IRUGO
| S_IWUSR
,
726 .size
= DS2781_USER_EEPROM_SIZE
,
727 .read
= ds2781_read_user_eeprom_bin
,
728 .write
= ds2781_write_user_eeprom_bin
,
731 static DEVICE_ATTR(pmod_enabled
, S_IRUGO
| S_IWUSR
, ds2781_get_pmod_enabled
,
732 ds2781_set_pmod_enabled
);
733 static DEVICE_ATTR(sense_resistor_value
, S_IRUGO
| S_IWUSR
,
734 ds2781_get_sense_resistor_value
, ds2781_set_sense_resistor_value
);
735 static DEVICE_ATTR(rsgain_setting
, S_IRUGO
| S_IWUSR
, ds2781_get_rsgain_setting
,
736 ds2781_set_rsgain_setting
);
737 static DEVICE_ATTR(pio_pin
, S_IRUGO
| S_IWUSR
, ds2781_get_pio_pin
,
741 static struct attribute
*ds2781_attributes
[] = {
742 &dev_attr_pmod_enabled
.attr
,
743 &dev_attr_sense_resistor_value
.attr
,
744 &dev_attr_rsgain_setting
.attr
,
745 &dev_attr_pio_pin
.attr
,
749 static const struct attribute_group ds2781_attr_group
= {
750 .attrs
= ds2781_attributes
,
753 static int ds2781_battery_probe(struct platform_device
*pdev
)
756 struct ds2781_device_info
*dev_info
;
758 dev_info
= devm_kzalloc(&pdev
->dev
, sizeof(*dev_info
), GFP_KERNEL
);
762 platform_set_drvdata(pdev
, dev_info
);
764 dev_info
->dev
= &pdev
->dev
;
765 dev_info
->w1_dev
= pdev
->dev
.parent
;
766 dev_info
->bat
.name
= dev_name(&pdev
->dev
);
767 dev_info
->bat
.type
= POWER_SUPPLY_TYPE_BATTERY
;
768 dev_info
->bat
.properties
= ds2781_battery_props
;
769 dev_info
->bat
.num_properties
= ARRAY_SIZE(ds2781_battery_props
);
770 dev_info
->bat
.get_property
= ds2781_battery_get_property
;
772 ret
= power_supply_register(&pdev
->dev
, &dev_info
->bat
);
774 dev_err(dev_info
->dev
, "failed to register battery\n");
778 ret
= sysfs_create_group(&dev_info
->bat
.dev
->kobj
, &ds2781_attr_group
);
780 dev_err(dev_info
->dev
, "failed to create sysfs group\n");
781 goto fail_unregister
;
784 ret
= sysfs_create_bin_file(&dev_info
->bat
.dev
->kobj
,
785 &ds2781_param_eeprom_bin_attr
);
787 dev_err(dev_info
->dev
,
788 "failed to create param eeprom bin file");
789 goto fail_remove_group
;
792 ret
= sysfs_create_bin_file(&dev_info
->bat
.dev
->kobj
,
793 &ds2781_user_eeprom_bin_attr
);
795 dev_err(dev_info
->dev
,
796 "failed to create user eeprom bin file");
797 goto fail_remove_bin_file
;
802 fail_remove_bin_file
:
803 sysfs_remove_bin_file(&dev_info
->bat
.dev
->kobj
,
804 &ds2781_param_eeprom_bin_attr
);
806 sysfs_remove_group(&dev_info
->bat
.dev
->kobj
, &ds2781_attr_group
);
808 power_supply_unregister(&dev_info
->bat
);
813 static int ds2781_battery_remove(struct platform_device
*pdev
)
815 struct ds2781_device_info
*dev_info
= platform_get_drvdata(pdev
);
817 /* remove attributes */
818 sysfs_remove_group(&dev_info
->bat
.dev
->kobj
, &ds2781_attr_group
);
820 power_supply_unregister(&dev_info
->bat
);
825 static struct platform_driver ds2781_battery_driver
= {
827 .name
= "ds2781-battery",
829 .probe
= ds2781_battery_probe
,
830 .remove
= ds2781_battery_remove
,
832 module_platform_driver(ds2781_battery_driver
);
834 MODULE_LICENSE("GPL");
835 MODULE_AUTHOR("Renata Sayakhova <renata@oktetlabs.ru>");
836 MODULE_DESCRIPTION("Maxim/Dallas DS2781 Stand-Alone Fuel Gauage IC driver");
837 MODULE_ALIAS("platform:ds2781-battery");