]> git.kernelconcepts.de Git - karo-tx-linux.git/blob - drivers/power/ds2781_battery.c
mxc: vpu: improve clk enable/disable handling
[karo-tx-linux.git] / drivers / power / ds2781_battery.c
1 /*
2  * 1-wire client/driver for the Maxim/Dallas DS2781 Stand-Alone Fuel Gauge IC
3  *
4  * Author: Renata Sayakhova <renata@oktetlabs.ru>
5  *
6  * Based on ds2780_battery drivers
7  *
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.
11  *
12  */
13
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/param.h>
17 #include <linux/pm.h>
18 #include <linux/platform_device.h>
19 #include <linux/power_supply.h>
20 #include <linux/idr.h>
21
22 #include "../w1/w1.h"
23 #include "../w1/slaves/w1_ds2781.h"
24
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)
35
36 struct ds2781_device_info {
37         struct device *dev;
38         struct power_supply bat;
39         struct device *w1_dev;
40 };
41
42 enum current_types {
43         CURRENT_NOW,
44         CURRENT_AVG,
45 };
46
47 static const char model[] = "DS2781";
48 static const char manufacturer[] = "Maxim/Dallas";
49
50 static inline struct ds2781_device_info *
51 to_ds2781_device_info(struct power_supply *psy)
52 {
53         return container_of(psy, struct ds2781_device_info, bat);
54 }
55
56 static inline struct power_supply *to_power_supply(struct device *dev)
57 {
58         return dev_get_drvdata(dev);
59 }
60
61 static inline int ds2781_battery_io(struct ds2781_device_info *dev_info,
62         char *buf, int addr, size_t count, int io)
63 {
64         return w1_ds2781_io(dev_info->w1_dev, buf, addr, count, io);
65 }
66
67 static int w1_ds2781_read(struct ds2781_device_info *dev_info, char *buf,
68                 int addr, size_t count)
69 {
70         return ds2781_battery_io(dev_info, buf, addr, count, 0);
71 }
72
73 static inline int ds2781_read8(struct ds2781_device_info *dev_info, u8 *val,
74         int addr)
75 {
76         return ds2781_battery_io(dev_info, val, addr, sizeof(u8), 0);
77 }
78
79 static int ds2781_read16(struct ds2781_device_info *dev_info, s16 *val,
80         int addr)
81 {
82         int ret;
83         u8 raw[2];
84
85         ret = ds2781_battery_io(dev_info, raw, addr, sizeof(raw), 0);
86         if (ret < 0)
87                 return ret;
88
89         *val = (raw[0] << 8) | raw[1];
90
91         return 0;
92 }
93
94 static inline int ds2781_read_block(struct ds2781_device_info *dev_info,
95         u8 *val, int addr, size_t count)
96 {
97         return ds2781_battery_io(dev_info, val, addr, count, 0);
98 }
99
100 static inline int ds2781_write(struct ds2781_device_info *dev_info, u8 *val,
101         int addr, size_t count)
102 {
103         return ds2781_battery_io(dev_info, val, addr, count, 1);
104 }
105
106 static inline int ds2781_store_eeprom(struct device *dev, int addr)
107 {
108         return w1_ds2781_eeprom_cmd(dev, addr, W1_DS2781_COPY_DATA);
109 }
110
111 static inline int ds2781_recall_eeprom(struct device *dev, int addr)
112 {
113         return w1_ds2781_eeprom_cmd(dev, addr, W1_DS2781_RECALL_DATA);
114 }
115
116 static int ds2781_save_eeprom(struct ds2781_device_info *dev_info, int reg)
117 {
118         int ret;
119
120         ret = ds2781_store_eeprom(dev_info->w1_dev, reg);
121         if (ret < 0)
122                 return ret;
123
124         ret = ds2781_recall_eeprom(dev_info->w1_dev, reg);
125         if (ret < 0)
126                 return ret;
127
128         return 0;
129 }
130
131 /* Set sense resistor value in mhos */
132 static int ds2781_set_sense_register(struct ds2781_device_info *dev_info,
133         u8 conductance)
134 {
135         int ret;
136
137         ret = ds2781_write(dev_info, &conductance,
138                                 DS2781_RSNSP, sizeof(u8));
139         if (ret < 0)
140                 return ret;
141
142         return ds2781_save_eeprom(dev_info, DS2781_RSNSP);
143 }
144
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,
147         u16 *rsgain)
148 {
149         return ds2781_read16(dev_info, rsgain, DS2781_RSGAIN_MSB);
150 }
151
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,
154         u16 rsgain)
155 {
156         int ret;
157         u8 raw[] = {rsgain >> 8, rsgain & 0xFF};
158
159         ret = ds2781_write(dev_info, raw,
160                                 DS2781_RSGAIN_MSB, sizeof(raw));
161         if (ret < 0)
162                 return ret;
163
164         return ds2781_save_eeprom(dev_info, DS2781_RSGAIN_MSB);
165 }
166
167 static int ds2781_get_voltage(struct ds2781_device_info *dev_info,
168         int *voltage_uV)
169 {
170         int ret;
171         char val[2];
172         int voltage_raw;
173
174         ret = w1_ds2781_read(dev_info, val, DS2781_VOLT_MSB, 2 * sizeof(u8));
175         if (ret < 0)
176                 return ret;
177         /*
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
185          */
186         voltage_raw = (val[0] << 3) |
187                 (val[1] >> 5);
188
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;
192
193         return 0;
194 }
195
196 static int ds2781_get_temperature(struct ds2781_device_info *dev_info,
197         int *temp)
198 {
199         int ret;
200         char val[2];
201         int temp_raw;
202
203         ret = w1_ds2781_read(dev_info, val, DS2781_TEMP_MSB, 2 * sizeof(u8));
204         if (ret < 0)
205                 return ret;
206         /*
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
210          * MSB register
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
215          */
216         temp_raw = ((val[0]) << 3) |
217                 (val[1] >> 5);
218         *temp = temp_raw + (temp_raw / 4);
219
220         return 0;
221 }
222
223 static int ds2781_get_current(struct ds2781_device_info *dev_info,
224         enum current_types type, int *current_uA)
225 {
226         int ret, sense_res;
227         s16 current_raw;
228         u8 sense_res_raw, reg_msb;
229
230         /*
231          * The units of measurement for current are dependent on the value of
232          * the sense resistor.
233          */
234         ret = ds2781_read8(dev_info, &sense_res_raw, DS2781_RSNSP);
235         if (ret < 0)
236                 return ret;
237
238         if (sense_res_raw == 0) {
239                 dev_err(dev_info->dev, "sense resistor value is 0\n");
240                 return -EINVAL;
241         }
242         sense_res = 1000 / sense_res_raw;
243
244         if (type == CURRENT_NOW)
245                 reg_msb = DS2781_CURRENT_MSB;
246         else if (type == CURRENT_AVG)
247                 reg_msb = DS2781_IAVG_MSB;
248         else
249                 return -EINVAL;
250
251         /*
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
256          * MSB register
257          * Bits 7 - 0 of the current value are in bits 7 - 0 of the current
258          * LSB register
259          */
260         ret = ds2781_read16(dev_info, &current_raw, reg_msb);
261         if (ret < 0)
262                 return ret;
263
264         *current_uA = current_raw * (DS2781_CURRENT_UNITS / sense_res);
265         return 0;
266 }
267
268 static int ds2781_get_accumulated_current(struct ds2781_device_info *dev_info,
269         int *accumulated_current)
270 {
271         int ret, sense_res;
272         s16 current_raw;
273         u8 sense_res_raw;
274
275         /*
276          * The units of measurement for accumulated current are dependent on
277          * the value of the sense resistor.
278          */
279         ret = ds2781_read8(dev_info, &sense_res_raw, DS2781_RSNSP);
280         if (ret < 0)
281                 return ret;
282
283         if (sense_res_raw == 0) {
284                 dev_err(dev_info->dev, "sense resistor value is 0\n");
285                 return -EINVAL;
286         }
287         sense_res = 1000 / sense_res_raw;
288
289         /*
290          * The ACR value is located in 16 bits across the ACR MSB and
291          * LSB registers
292          * Bits 15 - 8 of the ACR value are in bits 7 - 0 of the ACR
293          * MSB register
294          * Bits 7 - 0 of the ACR value are in bits 7 - 0 of the ACR
295          * LSB register
296          */
297         ret = ds2781_read16(dev_info, &current_raw, DS2781_ACR_MSB);
298         if (ret < 0)
299                 return ret;
300
301         *accumulated_current = current_raw * (DS2781_CHARGE_UNITS / sense_res);
302         return 0;
303 }
304
305 static int ds2781_get_capacity(struct ds2781_device_info *dev_info,
306         int *capacity)
307 {
308         int ret;
309         u8 raw;
310
311         ret = ds2781_read8(dev_info, &raw, DS2781_RARC);
312         if (ret < 0)
313                 return ret;
314
315         *capacity = raw;
316         return 0;
317 }
318
319 static int ds2781_get_status(struct ds2781_device_info *dev_info, int *status)
320 {
321         int ret, current_uA, capacity;
322
323         ret = ds2781_get_current(dev_info, CURRENT_NOW, &current_uA);
324         if (ret < 0)
325                 return ret;
326
327         ret = ds2781_get_capacity(dev_info, &capacity);
328         if (ret < 0)
329                 return ret;
330
331         if (power_supply_am_i_supplied(&dev_info->bat)) {
332                 if (capacity == 100)
333                         *status = POWER_SUPPLY_STATUS_FULL;
334                 else if (current_uA > 50000)
335                         *status = POWER_SUPPLY_STATUS_CHARGING;
336                 else
337                         *status = POWER_SUPPLY_STATUS_NOT_CHARGING;
338         } else {
339                 *status = POWER_SUPPLY_STATUS_DISCHARGING;
340         }
341         return 0;
342 }
343
344 static int ds2781_get_charge_now(struct ds2781_device_info *dev_info,
345         int *charge_now)
346 {
347         int ret;
348         u16 charge_raw;
349
350         /*
351          * The RAAC value is located in 16 bits across the RAAC MSB and
352          * LSB registers
353          * Bits 15 - 8 of the RAAC value are in bits 7 - 0 of the RAAC
354          * MSB register
355          * Bits 7 - 0 of the RAAC value are in bits 7 - 0 of the RAAC
356          * LSB register
357          */
358         ret = ds2781_read16(dev_info, &charge_raw, DS2781_RAAC_MSB);
359         if (ret < 0)
360                 return ret;
361
362         *charge_now = charge_raw * 1600;
363         return 0;
364 }
365
366 static int ds2781_get_control_register(struct ds2781_device_info *dev_info,
367         u8 *control_reg)
368 {
369         return ds2781_read8(dev_info, control_reg, DS2781_CONTROL);
370 }
371
372 static int ds2781_set_control_register(struct ds2781_device_info *dev_info,
373         u8 control_reg)
374 {
375         int ret;
376
377         ret = ds2781_write(dev_info, &control_reg,
378                                 DS2781_CONTROL, sizeof(u8));
379         if (ret < 0)
380                 return ret;
381
382         return ds2781_save_eeprom(dev_info, DS2781_CONTROL);
383 }
384
385 static int ds2781_battery_get_property(struct power_supply *psy,
386         enum power_supply_property psp,
387         union power_supply_propval *val)
388 {
389         int ret = 0;
390         struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
391
392         switch (psp) {
393         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
394                 ret = ds2781_get_voltage(dev_info, &val->intval);
395                 break;
396
397         case POWER_SUPPLY_PROP_TEMP:
398                 ret = ds2781_get_temperature(dev_info, &val->intval);
399                 break;
400
401         case POWER_SUPPLY_PROP_MODEL_NAME:
402                 val->strval = model;
403                 break;
404
405         case POWER_SUPPLY_PROP_MANUFACTURER:
406                 val->strval = manufacturer;
407                 break;
408
409         case POWER_SUPPLY_PROP_CURRENT_NOW:
410                 ret = ds2781_get_current(dev_info, CURRENT_NOW, &val->intval);
411                 break;
412
413         case POWER_SUPPLY_PROP_CURRENT_AVG:
414                 ret = ds2781_get_current(dev_info, CURRENT_AVG, &val->intval);
415                 break;
416
417         case POWER_SUPPLY_PROP_STATUS:
418                 ret = ds2781_get_status(dev_info, &val->intval);
419                 break;
420
421         case POWER_SUPPLY_PROP_CAPACITY:
422                 ret = ds2781_get_capacity(dev_info, &val->intval);
423                 break;
424
425         case POWER_SUPPLY_PROP_CHARGE_COUNTER:
426                 ret = ds2781_get_accumulated_current(dev_info, &val->intval);
427                 break;
428
429         case POWER_SUPPLY_PROP_CHARGE_NOW:
430                 ret = ds2781_get_charge_now(dev_info, &val->intval);
431                 break;
432
433         default:
434                 ret = -EINVAL;
435         }
436
437         return ret;
438 }
439
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,
451 };
452
453 static ssize_t ds2781_get_pmod_enabled(struct device *dev,
454         struct device_attribute *attr,
455         char *buf)
456 {
457         int ret;
458         u8 control_reg;
459         struct power_supply *psy = to_power_supply(dev);
460         struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
461
462         /* Get power mode */
463         ret = ds2781_get_control_register(dev_info, &control_reg);
464         if (ret < 0)
465                 return ret;
466
467         return sprintf(buf, "%d\n",
468                  !!(control_reg & DS2781_CONTROL_PMOD));
469 }
470
471 static ssize_t ds2781_set_pmod_enabled(struct device *dev,
472         struct device_attribute *attr,
473         const char *buf,
474         size_t count)
475 {
476         int ret;
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);
480
481         /* Set power mode */
482         ret = ds2781_get_control_register(dev_info, &control_reg);
483         if (ret < 0)
484                 return ret;
485
486         ret = kstrtou8(buf, 0, &new_setting);
487         if (ret < 0)
488                 return ret;
489
490         if ((new_setting != 0) && (new_setting != 1)) {
491                 dev_err(dev_info->dev, "Invalid pmod setting (0 or 1)\n");
492                 return -EINVAL;
493         }
494
495         if (new_setting)
496                 control_reg |= DS2781_CONTROL_PMOD;
497         else
498                 control_reg &= ~DS2781_CONTROL_PMOD;
499
500         ret = ds2781_set_control_register(dev_info, control_reg);
501         if (ret < 0)
502                 return ret;
503
504         return count;
505 }
506
507 static ssize_t ds2781_get_sense_resistor_value(struct device *dev,
508         struct device_attribute *attr,
509         char *buf)
510 {
511         int ret;
512         u8 sense_resistor;
513         struct power_supply *psy = to_power_supply(dev);
514         struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
515
516         ret = ds2781_read8(dev_info, &sense_resistor, DS2781_RSNSP);
517         if (ret < 0)
518                 return ret;
519
520         ret = sprintf(buf, "%d\n", sense_resistor);
521         return ret;
522 }
523
524 static ssize_t ds2781_set_sense_resistor_value(struct device *dev,
525         struct device_attribute *attr,
526         const char *buf,
527         size_t count)
528 {
529         int ret;
530         u8 new_setting;
531         struct power_supply *psy = to_power_supply(dev);
532         struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
533
534         ret = kstrtou8(buf, 0, &new_setting);
535         if (ret < 0)
536                 return ret;
537
538         ret = ds2781_set_sense_register(dev_info, new_setting);
539         if (ret < 0)
540                 return ret;
541
542         return count;
543 }
544
545 static ssize_t ds2781_get_rsgain_setting(struct device *dev,
546         struct device_attribute *attr,
547         char *buf)
548 {
549         int ret;
550         u16 rsgain;
551         struct power_supply *psy = to_power_supply(dev);
552         struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
553
554         ret = ds2781_get_rsgain_register(dev_info, &rsgain);
555         if (ret < 0)
556                 return ret;
557
558         return sprintf(buf, "%d\n", rsgain);
559 }
560
561 static ssize_t ds2781_set_rsgain_setting(struct device *dev,
562         struct device_attribute *attr,
563         const char *buf,
564         size_t count)
565 {
566         int ret;
567         u16 new_setting;
568         struct power_supply *psy = to_power_supply(dev);
569         struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
570
571         ret = kstrtou16(buf, 0, &new_setting);
572         if (ret < 0)
573                 return ret;
574
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");
578                 return -EINVAL;
579         }
580
581         ret = ds2781_set_rsgain_register(dev_info, new_setting);
582         if (ret < 0)
583                 return ret;
584
585         return count;
586 }
587
588 static ssize_t ds2781_get_pio_pin(struct device *dev,
589         struct device_attribute *attr,
590         char *buf)
591 {
592         int ret;
593         u8 sfr;
594         struct power_supply *psy = to_power_supply(dev);
595         struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
596
597         ret = ds2781_read8(dev_info, &sfr, DS2781_SFR);
598         if (ret < 0)
599                 return ret;
600
601         ret = sprintf(buf, "%d\n", sfr & DS2781_SFR_PIOSC);
602         return ret;
603 }
604
605 static ssize_t ds2781_set_pio_pin(struct device *dev,
606         struct device_attribute *attr,
607         const char *buf,
608         size_t count)
609 {
610         int ret;
611         u8 new_setting;
612         struct power_supply *psy = to_power_supply(dev);
613         struct ds2781_device_info *dev_info = to_ds2781_device_info(psy);
614
615         ret = kstrtou8(buf, 0, &new_setting);
616         if (ret < 0)
617                 return ret;
618
619         if ((new_setting != 0) && (new_setting != 1)) {
620                 dev_err(dev_info->dev, "Invalid pio_pin setting (0 or 1)\n");
621                 return -EINVAL;
622         }
623
624         ret = ds2781_write(dev_info, &new_setting,
625                                 DS2781_SFR, sizeof(u8));
626         if (ret < 0)
627                 return ret;
628
629         return count;
630 }
631
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)
636 {
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);
640
641         count = min_t(loff_t, count, DS2781_PARAM_EEPROM_SIZE - off);
642
643         return ds2781_read_block(dev_info, buf,
644                                 DS2781_EEPROM_BLOCK1_START + off, count);
645 }
646
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)
651 {
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);
655         int ret;
656
657         count = min_t(loff_t, count, DS2781_PARAM_EEPROM_SIZE - off);
658
659         ret = ds2781_write(dev_info, buf,
660                                 DS2781_EEPROM_BLOCK1_START + off, count);
661         if (ret < 0)
662                 return ret;
663
664         ret = ds2781_save_eeprom(dev_info, DS2781_EEPROM_BLOCK1_START);
665         if (ret < 0)
666                 return ret;
667
668         return count;
669 }
670
671 static struct bin_attribute ds2781_param_eeprom_bin_attr = {
672         .attr = {
673                 .name = "param_eeprom",
674                 .mode = S_IRUGO | S_IWUSR,
675         },
676         .size = DS2781_PARAM_EEPROM_SIZE,
677         .read = ds2781_read_param_eeprom_bin,
678         .write = ds2781_write_param_eeprom_bin,
679 };
680
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)
685 {
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);
689
690         count = min_t(loff_t, count, DS2781_USER_EEPROM_SIZE - off);
691
692         return ds2781_read_block(dev_info, buf,
693                                 DS2781_EEPROM_BLOCK0_START + off, count);
694
695 }
696
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)
701 {
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);
705         int ret;
706
707         count = min_t(loff_t, count, DS2781_USER_EEPROM_SIZE - off);
708
709         ret = ds2781_write(dev_info, buf,
710                                 DS2781_EEPROM_BLOCK0_START + off, count);
711         if (ret < 0)
712                 return ret;
713
714         ret = ds2781_save_eeprom(dev_info, DS2781_EEPROM_BLOCK0_START);
715         if (ret < 0)
716                 return ret;
717
718         return count;
719 }
720
721 static struct bin_attribute ds2781_user_eeprom_bin_attr = {
722         .attr = {
723                 .name = "user_eeprom",
724                 .mode = S_IRUGO | S_IWUSR,
725         },
726         .size = DS2781_USER_EEPROM_SIZE,
727         .read = ds2781_read_user_eeprom_bin,
728         .write = ds2781_write_user_eeprom_bin,
729 };
730
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,
738         ds2781_set_pio_pin);
739
740
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,
746         NULL
747 };
748
749 static const struct attribute_group ds2781_attr_group = {
750         .attrs = ds2781_attributes,
751 };
752
753 static int ds2781_battery_probe(struct platform_device *pdev)
754 {
755         int ret = 0;
756         struct ds2781_device_info *dev_info;
757
758         dev_info = devm_kzalloc(&pdev->dev, sizeof(*dev_info), GFP_KERNEL);
759         if (!dev_info)
760                 return -ENOMEM;
761
762         platform_set_drvdata(pdev, dev_info);
763
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;
771
772         ret = power_supply_register(&pdev->dev, &dev_info->bat);
773         if (ret) {
774                 dev_err(dev_info->dev, "failed to register battery\n");
775                 goto fail;
776         }
777
778         ret = sysfs_create_group(&dev_info->bat.dev->kobj, &ds2781_attr_group);
779         if (ret) {
780                 dev_err(dev_info->dev, "failed to create sysfs group\n");
781                 goto fail_unregister;
782         }
783
784         ret = sysfs_create_bin_file(&dev_info->bat.dev->kobj,
785                                         &ds2781_param_eeprom_bin_attr);
786         if (ret) {
787                 dev_err(dev_info->dev,
788                                 "failed to create param eeprom bin file");
789                 goto fail_remove_group;
790         }
791
792         ret = sysfs_create_bin_file(&dev_info->bat.dev->kobj,
793                                         &ds2781_user_eeprom_bin_attr);
794         if (ret) {
795                 dev_err(dev_info->dev,
796                                 "failed to create user eeprom bin file");
797                 goto fail_remove_bin_file;
798         }
799
800         return 0;
801
802 fail_remove_bin_file:
803         sysfs_remove_bin_file(&dev_info->bat.dev->kobj,
804                                 &ds2781_param_eeprom_bin_attr);
805 fail_remove_group:
806         sysfs_remove_group(&dev_info->bat.dev->kobj, &ds2781_attr_group);
807 fail_unregister:
808         power_supply_unregister(&dev_info->bat);
809 fail:
810         return ret;
811 }
812
813 static int ds2781_battery_remove(struct platform_device *pdev)
814 {
815         struct ds2781_device_info *dev_info = platform_get_drvdata(pdev);
816
817         /* remove attributes */
818         sysfs_remove_group(&dev_info->bat.dev->kobj, &ds2781_attr_group);
819
820         power_supply_unregister(&dev_info->bat);
821
822         return 0;
823 }
824
825 static struct platform_driver ds2781_battery_driver = {
826         .driver = {
827                 .name = "ds2781-battery",
828         },
829         .probe    = ds2781_battery_probe,
830         .remove   = ds2781_battery_remove,
831 };
832 module_platform_driver(ds2781_battery_driver);
833
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");
838