xref: /openbmc/linux/drivers/acpi/sbs.c (revision 5b4cb650)
1 /*
2  *  sbs.c - ACPI Smart Battery System Driver ($Revision: 2.0 $)
3  *
4  *  Copyright (c) 2007 Alexey Starikovskiy <astarikovskiy@suse.de>
5  *  Copyright (c) 2005-2007 Vladimir Lebedev <vladimir.p.lebedev@intel.com>
6  *  Copyright (c) 2005 Rich Townsend <rhdt@bartol.udel.edu>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or (at
13  *  your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful, but
16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  *  General Public License for more details.
19  *
20  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21  */
22 
23 #include <linux/init.h>
24 #include <linux/slab.h>
25 #include <linux/module.h>
26 #include <linux/moduleparam.h>
27 #include <linux/kernel.h>
28 
29 #include <linux/acpi.h>
30 #include <linux/timer.h>
31 #include <linux/jiffies.h>
32 #include <linux/delay.h>
33 #include <linux/power_supply.h>
34 #include <linux/platform_data/x86/apple.h>
35 #include <acpi/battery.h>
36 
37 #include "sbshc.h"
38 
39 #define PREFIX "ACPI: "
40 
41 #define ACPI_SBS_CLASS			"sbs"
42 #define ACPI_AC_CLASS			"ac_adapter"
43 #define ACPI_SBS_DEVICE_NAME		"Smart Battery System"
44 #define ACPI_SBS_FILE_INFO		"info"
45 #define ACPI_SBS_FILE_STATE		"state"
46 #define ACPI_SBS_FILE_ALARM		"alarm"
47 #define ACPI_BATTERY_DIR_NAME		"BAT%i"
48 #define ACPI_AC_DIR_NAME		"AC0"
49 
50 #define ACPI_SBS_NOTIFY_STATUS		0x80
51 #define ACPI_SBS_NOTIFY_INFO		0x81
52 
53 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
54 MODULE_DESCRIPTION("Smart Battery System ACPI interface driver");
55 MODULE_LICENSE("GPL");
56 
57 static unsigned int cache_time = 1000;
58 module_param(cache_time, uint, 0644);
59 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
60 
61 #define MAX_SBS_BAT			4
62 #define ACPI_SBS_BLOCK_MAX		32
63 
64 static const struct acpi_device_id sbs_device_ids[] = {
65 	{"ACPI0002", 0},
66 	{"", 0},
67 };
68 MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
69 
70 struct acpi_battery {
71 	struct power_supply *bat;
72 	struct power_supply_desc bat_desc;
73 	struct acpi_sbs *sbs;
74 	unsigned long update_time;
75 	char name[8];
76 	char manufacturer_name[ACPI_SBS_BLOCK_MAX];
77 	char device_name[ACPI_SBS_BLOCK_MAX];
78 	char device_chemistry[ACPI_SBS_BLOCK_MAX];
79 	u16 alarm_capacity;
80 	u16 full_charge_capacity;
81 	u16 design_capacity;
82 	u16 design_voltage;
83 	u16 serial_number;
84 	u16 cycle_count;
85 	u16 temp_now;
86 	u16 voltage_now;
87 	s16 rate_now;
88 	s16 rate_avg;
89 	u16 capacity_now;
90 	u16 state_of_charge;
91 	u16 state;
92 	u16 mode;
93 	u16 spec;
94 	u8 id;
95 	u8 present:1;
96 	u8 have_sysfs_alarm:1;
97 };
98 
99 #define to_acpi_battery(x) power_supply_get_drvdata(x)
100 
101 struct acpi_sbs {
102 	struct power_supply *charger;
103 	struct acpi_device *device;
104 	struct acpi_smb_hc *hc;
105 	struct mutex lock;
106 	struct acpi_battery battery[MAX_SBS_BAT];
107 	u8 batteries_supported:4;
108 	u8 manager_present:1;
109 	u8 charger_present:1;
110 	u8 charger_exists:1;
111 };
112 
113 #define to_acpi_sbs(x) power_supply_get_drvdata(x)
114 
115 static int acpi_sbs_remove(struct acpi_device *device);
116 static int acpi_battery_get_state(struct acpi_battery *battery);
117 
118 static inline int battery_scale(int log)
119 {
120 	int scale = 1;
121 	while (log--)
122 		scale *= 10;
123 	return scale;
124 }
125 
126 static inline int acpi_battery_vscale(struct acpi_battery *battery)
127 {
128 	return battery_scale((battery->spec & 0x0f00) >> 8);
129 }
130 
131 static inline int acpi_battery_ipscale(struct acpi_battery *battery)
132 {
133 	return battery_scale((battery->spec & 0xf000) >> 12);
134 }
135 
136 static inline int acpi_battery_mode(struct acpi_battery *battery)
137 {
138 	return (battery->mode & 0x8000);
139 }
140 
141 static inline int acpi_battery_scale(struct acpi_battery *battery)
142 {
143 	return (acpi_battery_mode(battery) ? 10 : 1) *
144 	    acpi_battery_ipscale(battery);
145 }
146 
147 static int sbs_get_ac_property(struct power_supply *psy,
148 			       enum power_supply_property psp,
149 			       union power_supply_propval *val)
150 {
151 	struct acpi_sbs *sbs = to_acpi_sbs(psy);
152 	switch (psp) {
153 	case POWER_SUPPLY_PROP_ONLINE:
154 		val->intval = sbs->charger_present;
155 		break;
156 	default:
157 		return -EINVAL;
158 	}
159 	return 0;
160 }
161 
162 static int acpi_battery_technology(struct acpi_battery *battery)
163 {
164 	if (!strcasecmp("NiCd", battery->device_chemistry))
165 		return POWER_SUPPLY_TECHNOLOGY_NiCd;
166 	if (!strcasecmp("NiMH", battery->device_chemistry))
167 		return POWER_SUPPLY_TECHNOLOGY_NiMH;
168 	if (!strcasecmp("LION", battery->device_chemistry))
169 		return POWER_SUPPLY_TECHNOLOGY_LION;
170 	if (!strcasecmp("LiP", battery->device_chemistry))
171 		return POWER_SUPPLY_TECHNOLOGY_LIPO;
172 	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
173 }
174 
175 static int acpi_sbs_battery_get_property(struct power_supply *psy,
176 					 enum power_supply_property psp,
177 					 union power_supply_propval *val)
178 {
179 	struct acpi_battery *battery = to_acpi_battery(psy);
180 
181 	if ((!battery->present) && psp != POWER_SUPPLY_PROP_PRESENT)
182 		return -ENODEV;
183 
184 	acpi_battery_get_state(battery);
185 	switch (psp) {
186 	case POWER_SUPPLY_PROP_STATUS:
187 		if (battery->rate_now < 0)
188 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
189 		else if (battery->rate_now > 0)
190 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
191 		else
192 			val->intval = POWER_SUPPLY_STATUS_FULL;
193 		break;
194 	case POWER_SUPPLY_PROP_PRESENT:
195 		val->intval = battery->present;
196 		break;
197 	case POWER_SUPPLY_PROP_TECHNOLOGY:
198 		val->intval = acpi_battery_technology(battery);
199 		break;
200 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
201 		val->intval = battery->cycle_count;
202 		break;
203 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
204 		val->intval = battery->design_voltage *
205 			acpi_battery_vscale(battery) * 1000;
206 		break;
207 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
208 		val->intval = battery->voltage_now *
209 				acpi_battery_vscale(battery) * 1000;
210 		break;
211 	case POWER_SUPPLY_PROP_CURRENT_NOW:
212 	case POWER_SUPPLY_PROP_POWER_NOW:
213 		val->intval = abs(battery->rate_now) *
214 				acpi_battery_ipscale(battery) * 1000;
215 		val->intval *= (acpi_battery_mode(battery)) ?
216 				(battery->voltage_now *
217 				acpi_battery_vscale(battery) / 1000) : 1;
218 		break;
219 	case POWER_SUPPLY_PROP_CURRENT_AVG:
220 	case POWER_SUPPLY_PROP_POWER_AVG:
221 		val->intval = abs(battery->rate_avg) *
222 				acpi_battery_ipscale(battery) * 1000;
223 		val->intval *= (acpi_battery_mode(battery)) ?
224 				(battery->voltage_now *
225 				acpi_battery_vscale(battery) / 1000) : 1;
226 		break;
227 	case POWER_SUPPLY_PROP_CAPACITY:
228 		val->intval = battery->state_of_charge;
229 		break;
230 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
231 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
232 		val->intval = battery->design_capacity *
233 			acpi_battery_scale(battery) * 1000;
234 		break;
235 	case POWER_SUPPLY_PROP_CHARGE_FULL:
236 	case POWER_SUPPLY_PROP_ENERGY_FULL:
237 		val->intval = battery->full_charge_capacity *
238 			acpi_battery_scale(battery) * 1000;
239 		break;
240 	case POWER_SUPPLY_PROP_CHARGE_NOW:
241 	case POWER_SUPPLY_PROP_ENERGY_NOW:
242 		val->intval = battery->capacity_now *
243 				acpi_battery_scale(battery) * 1000;
244 		break;
245 	case POWER_SUPPLY_PROP_TEMP:
246 		val->intval = battery->temp_now - 2730;	// dK -> dC
247 		break;
248 	case POWER_SUPPLY_PROP_MODEL_NAME:
249 		val->strval = battery->device_name;
250 		break;
251 	case POWER_SUPPLY_PROP_MANUFACTURER:
252 		val->strval = battery->manufacturer_name;
253 		break;
254 	default:
255 		return -EINVAL;
256 	}
257 	return 0;
258 }
259 
260 static enum power_supply_property sbs_ac_props[] = {
261 	POWER_SUPPLY_PROP_ONLINE,
262 };
263 
264 static enum power_supply_property sbs_charge_battery_props[] = {
265 	POWER_SUPPLY_PROP_STATUS,
266 	POWER_SUPPLY_PROP_PRESENT,
267 	POWER_SUPPLY_PROP_TECHNOLOGY,
268 	POWER_SUPPLY_PROP_CYCLE_COUNT,
269 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
270 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
271 	POWER_SUPPLY_PROP_CURRENT_NOW,
272 	POWER_SUPPLY_PROP_CURRENT_AVG,
273 	POWER_SUPPLY_PROP_CAPACITY,
274 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
275 	POWER_SUPPLY_PROP_CHARGE_FULL,
276 	POWER_SUPPLY_PROP_CHARGE_NOW,
277 	POWER_SUPPLY_PROP_TEMP,
278 	POWER_SUPPLY_PROP_MODEL_NAME,
279 	POWER_SUPPLY_PROP_MANUFACTURER,
280 };
281 
282 static enum power_supply_property sbs_energy_battery_props[] = {
283 	POWER_SUPPLY_PROP_STATUS,
284 	POWER_SUPPLY_PROP_PRESENT,
285 	POWER_SUPPLY_PROP_TECHNOLOGY,
286 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
287 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
288 	POWER_SUPPLY_PROP_CURRENT_NOW,
289 	POWER_SUPPLY_PROP_CURRENT_AVG,
290 	POWER_SUPPLY_PROP_POWER_NOW,
291 	POWER_SUPPLY_PROP_POWER_AVG,
292 	POWER_SUPPLY_PROP_CAPACITY,
293 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
294 	POWER_SUPPLY_PROP_ENERGY_FULL,
295 	POWER_SUPPLY_PROP_ENERGY_NOW,
296 	POWER_SUPPLY_PROP_TEMP,
297 	POWER_SUPPLY_PROP_MODEL_NAME,
298 	POWER_SUPPLY_PROP_MANUFACTURER,
299 };
300 
301 static const struct power_supply_desc acpi_sbs_charger_desc = {
302 	.name		= "sbs-charger",
303 	.type		= POWER_SUPPLY_TYPE_MAINS,
304 	.properties	= sbs_ac_props,
305 	.num_properties	= ARRAY_SIZE(sbs_ac_props),
306 	.get_property	= sbs_get_ac_property,
307 };
308 
309 /* --------------------------------------------------------------------------
310                             Smart Battery System Management
311    -------------------------------------------------------------------------- */
312 
313 struct acpi_battery_reader {
314 	u8 command;		/* command for battery */
315 	u8 mode;		/* word or block? */
316 	size_t offset;		/* offset inside struct acpi_sbs_battery */
317 };
318 
319 static struct acpi_battery_reader info_readers[] = {
320 	{0x01, SMBUS_READ_WORD, offsetof(struct acpi_battery, alarm_capacity)},
321 	{0x03, SMBUS_READ_WORD, offsetof(struct acpi_battery, mode)},
322 	{0x10, SMBUS_READ_WORD, offsetof(struct acpi_battery, full_charge_capacity)},
323 	{0x17, SMBUS_READ_WORD, offsetof(struct acpi_battery, cycle_count)},
324 	{0x18, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_capacity)},
325 	{0x19, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_voltage)},
326 	{0x1a, SMBUS_READ_WORD, offsetof(struct acpi_battery, spec)},
327 	{0x1c, SMBUS_READ_WORD, offsetof(struct acpi_battery, serial_number)},
328 	{0x20, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, manufacturer_name)},
329 	{0x21, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_name)},
330 	{0x22, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_chemistry)},
331 };
332 
333 static struct acpi_battery_reader state_readers[] = {
334 	{0x08, SMBUS_READ_WORD, offsetof(struct acpi_battery, temp_now)},
335 	{0x09, SMBUS_READ_WORD, offsetof(struct acpi_battery, voltage_now)},
336 	{0x0a, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_now)},
337 	{0x0b, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_avg)},
338 	{0x0f, SMBUS_READ_WORD, offsetof(struct acpi_battery, capacity_now)},
339 	{0x0e, SMBUS_READ_WORD, offsetof(struct acpi_battery, state_of_charge)},
340 	{0x16, SMBUS_READ_WORD, offsetof(struct acpi_battery, state)},
341 };
342 
343 static int acpi_manager_get_info(struct acpi_sbs *sbs)
344 {
345 	int result = 0;
346 	u16 battery_system_info;
347 
348 	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,
349 				 0x04, (u8 *)&battery_system_info);
350 	if (!result)
351 		sbs->batteries_supported = battery_system_info & 0x000f;
352 	return result;
353 }
354 
355 static int acpi_battery_get_info(struct acpi_battery *battery)
356 {
357 	int i, result = 0;
358 
359 	for (i = 0; i < ARRAY_SIZE(info_readers); ++i) {
360 		result = acpi_smbus_read(battery->sbs->hc,
361 					 info_readers[i].mode,
362 					 ACPI_SBS_BATTERY,
363 					 info_readers[i].command,
364 					 (u8 *) battery +
365 						info_readers[i].offset);
366 		if (result)
367 			break;
368 	}
369 	return result;
370 }
371 
372 static int acpi_battery_get_state(struct acpi_battery *battery)
373 {
374 	int i, result = 0;
375 
376 	if (battery->update_time &&
377 	    time_before(jiffies, battery->update_time +
378 				msecs_to_jiffies(cache_time)))
379 		return 0;
380 	for (i = 0; i < ARRAY_SIZE(state_readers); ++i) {
381 		result = acpi_smbus_read(battery->sbs->hc,
382 					 state_readers[i].mode,
383 					 ACPI_SBS_BATTERY,
384 					 state_readers[i].command,
385 				         (u8 *)battery +
386 						state_readers[i].offset);
387 		if (result)
388 			goto end;
389 	}
390       end:
391 	battery->update_time = jiffies;
392 	return result;
393 }
394 
395 static int acpi_battery_get_alarm(struct acpi_battery *battery)
396 {
397 	return acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
398 				 ACPI_SBS_BATTERY, 0x01,
399 				 (u8 *)&battery->alarm_capacity);
400 }
401 
402 static int acpi_battery_set_alarm(struct acpi_battery *battery)
403 {
404 	struct acpi_sbs *sbs = battery->sbs;
405 	u16 value, sel = 1 << (battery->id + 12);
406 
407 	int ret;
408 
409 
410 	if (sbs->manager_present) {
411 		ret = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,
412 				0x01, (u8 *)&value);
413 		if (ret)
414 			goto end;
415 		if ((value & 0xf000) != sel) {
416 			value &= 0x0fff;
417 			value |= sel;
418 			ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD,
419 					 ACPI_SBS_MANAGER,
420 					 0x01, (u8 *)&value, 2);
421 			if (ret)
422 				goto end;
423 		}
424 	}
425 	ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD, ACPI_SBS_BATTERY,
426 				0x01, (u8 *)&battery->alarm_capacity, 2);
427       end:
428 	return ret;
429 }
430 
431 static int acpi_ac_get_present(struct acpi_sbs *sbs)
432 {
433 	int result;
434 	u16 status;
435 
436 	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_CHARGER,
437 				 0x13, (u8 *) & status);
438 
439 	if (result)
440 		return result;
441 
442 	/*
443 	 * The spec requires that bit 4 always be 1. If it's not set, assume
444 	 * that the implementation doesn't support an SBS charger.
445 	 *
446 	 * And on some MacBooks a status of 0xffff is always returned, no
447 	 * matter whether the charger is plugged in or not, which is also
448 	 * wrong, so ignore the SBS charger for those too.
449 	 */
450 	if (!((status >> 4) & 0x1) || status == 0xffff)
451 		return -ENODEV;
452 
453 	sbs->charger_present = (status >> 15) & 0x1;
454 	return 0;
455 }
456 
457 static ssize_t acpi_battery_alarm_show(struct device *dev,
458 					struct device_attribute *attr,
459 					char *buf)
460 {
461 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
462 	acpi_battery_get_alarm(battery);
463 	return sprintf(buf, "%d\n", battery->alarm_capacity *
464 				acpi_battery_scale(battery) * 1000);
465 }
466 
467 static ssize_t acpi_battery_alarm_store(struct device *dev,
468 					struct device_attribute *attr,
469 					const char *buf, size_t count)
470 {
471 	unsigned long x;
472 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
473 	if (sscanf(buf, "%lu\n", &x) == 1)
474 		battery->alarm_capacity = x /
475 			(1000 * acpi_battery_scale(battery));
476 	if (battery->present)
477 		acpi_battery_set_alarm(battery);
478 	return count;
479 }
480 
481 static const struct device_attribute alarm_attr = {
482 	.attr = {.name = "alarm", .mode = 0644},
483 	.show = acpi_battery_alarm_show,
484 	.store = acpi_battery_alarm_store,
485 };
486 
487 /* --------------------------------------------------------------------------
488                                  Driver Interface
489    -------------------------------------------------------------------------- */
490 static int acpi_battery_read(struct acpi_battery *battery)
491 {
492 	int result = 0, saved_present = battery->present;
493 	u16 state;
494 
495 	if (battery->sbs->manager_present) {
496 		result = acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
497 				ACPI_SBS_MANAGER, 0x01, (u8 *)&state);
498 		if (!result)
499 			battery->present = state & (1 << battery->id);
500 		state &= 0x0fff;
501 		state |= 1 << (battery->id + 12);
502 		acpi_smbus_write(battery->sbs->hc, SMBUS_WRITE_WORD,
503 				  ACPI_SBS_MANAGER, 0x01, (u8 *)&state, 2);
504 	} else if (battery->id == 0)
505 		battery->present = 1;
506 
507 	if (result || !battery->present)
508 		return result;
509 
510 	if (saved_present != battery->present) {
511 		battery->update_time = 0;
512 		result = acpi_battery_get_info(battery);
513 		if (result) {
514 			battery->present = 0;
515 			return result;
516 		}
517 	}
518 	result = acpi_battery_get_state(battery);
519 	if (result)
520 		battery->present = 0;
521 	return result;
522 }
523 
524 /* Smart Battery */
525 static int acpi_battery_add(struct acpi_sbs *sbs, int id)
526 {
527 	struct acpi_battery *battery = &sbs->battery[id];
528 	struct power_supply_config psy_cfg = { .drv_data = battery, };
529 	int result;
530 
531 	battery->id = id;
532 	battery->sbs = sbs;
533 	result = acpi_battery_read(battery);
534 	if (result)
535 		return result;
536 
537 	sprintf(battery->name, ACPI_BATTERY_DIR_NAME, id);
538 	battery->bat_desc.name = battery->name;
539 	battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
540 	if (!acpi_battery_mode(battery)) {
541 		battery->bat_desc.properties = sbs_charge_battery_props;
542 		battery->bat_desc.num_properties =
543 		    ARRAY_SIZE(sbs_charge_battery_props);
544 	} else {
545 		battery->bat_desc.properties = sbs_energy_battery_props;
546 		battery->bat_desc.num_properties =
547 		    ARRAY_SIZE(sbs_energy_battery_props);
548 	}
549 	battery->bat_desc.get_property = acpi_sbs_battery_get_property;
550 	battery->bat = power_supply_register(&sbs->device->dev,
551 					&battery->bat_desc, &psy_cfg);
552 	if (IS_ERR(battery->bat)) {
553 		result = PTR_ERR(battery->bat);
554 		battery->bat = NULL;
555 		goto end;
556 	}
557 
558 	result = device_create_file(&battery->bat->dev, &alarm_attr);
559 	if (result)
560 		goto end;
561 	battery->have_sysfs_alarm = 1;
562       end:
563 	printk(KERN_INFO PREFIX "%s [%s]: Battery Slot [%s] (battery %s)\n",
564 	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
565 	       battery->name, battery->present ? "present" : "absent");
566 	return result;
567 }
568 
569 static void acpi_battery_remove(struct acpi_sbs *sbs, int id)
570 {
571 	struct acpi_battery *battery = &sbs->battery[id];
572 
573 	if (battery->bat) {
574 		if (battery->have_sysfs_alarm)
575 			device_remove_file(&battery->bat->dev, &alarm_attr);
576 		power_supply_unregister(battery->bat);
577 	}
578 }
579 
580 static int acpi_charger_add(struct acpi_sbs *sbs)
581 {
582 	int result;
583 	struct power_supply_config psy_cfg = { .drv_data = sbs, };
584 
585 	result = acpi_ac_get_present(sbs);
586 	if (result)
587 		goto end;
588 
589 	sbs->charger_exists = 1;
590 	sbs->charger = power_supply_register(&sbs->device->dev,
591 					&acpi_sbs_charger_desc, &psy_cfg);
592 	if (IS_ERR(sbs->charger)) {
593 		result = PTR_ERR(sbs->charger);
594 		sbs->charger = NULL;
595 	}
596 	printk(KERN_INFO PREFIX "%s [%s]: AC Adapter [%s] (%s)\n",
597 	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
598 	       ACPI_AC_DIR_NAME, sbs->charger_present ? "on-line" : "off-line");
599       end:
600 	return result;
601 }
602 
603 static void acpi_charger_remove(struct acpi_sbs *sbs)
604 {
605 	if (sbs->charger)
606 		power_supply_unregister(sbs->charger);
607 }
608 
609 static void acpi_sbs_callback(void *context)
610 {
611 	int id;
612 	struct acpi_sbs *sbs = context;
613 	struct acpi_battery *bat;
614 	u8 saved_charger_state = sbs->charger_present;
615 	u8 saved_battery_state;
616 
617 	if (sbs->charger_exists) {
618 		acpi_ac_get_present(sbs);
619 		if (sbs->charger_present != saved_charger_state)
620 			kobject_uevent(&sbs->charger->dev.kobj, KOBJ_CHANGE);
621 	}
622 
623 	if (sbs->manager_present) {
624 		for (id = 0; id < MAX_SBS_BAT; ++id) {
625 			if (!(sbs->batteries_supported & (1 << id)))
626 				continue;
627 			bat = &sbs->battery[id];
628 			saved_battery_state = bat->present;
629 			acpi_battery_read(bat);
630 			if (saved_battery_state == bat->present)
631 				continue;
632 			kobject_uevent(&bat->bat->dev.kobj, KOBJ_CHANGE);
633 		}
634 	}
635 }
636 
637 static int acpi_sbs_add(struct acpi_device *device)
638 {
639 	struct acpi_sbs *sbs;
640 	int result = 0;
641 	int id;
642 
643 	sbs = kzalloc(sizeof(struct acpi_sbs), GFP_KERNEL);
644 	if (!sbs) {
645 		result = -ENOMEM;
646 		goto end;
647 	}
648 
649 	mutex_init(&sbs->lock);
650 
651 	sbs->hc = acpi_driver_data(device->parent);
652 	sbs->device = device;
653 	strcpy(acpi_device_name(device), ACPI_SBS_DEVICE_NAME);
654 	strcpy(acpi_device_class(device), ACPI_SBS_CLASS);
655 	device->driver_data = sbs;
656 
657 	result = acpi_charger_add(sbs);
658 	if (result && result != -ENODEV)
659 		goto end;
660 
661 	result = 0;
662 
663 	if (!x86_apple_machine) {
664 		result = acpi_manager_get_info(sbs);
665 		if (!result) {
666 			sbs->manager_present = 1;
667 			for (id = 0; id < MAX_SBS_BAT; ++id)
668 				if ((sbs->batteries_supported & (1 << id)))
669 					acpi_battery_add(sbs, id);
670 		}
671 	}
672 
673 	if (!sbs->manager_present)
674 		acpi_battery_add(sbs, 0);
675 
676 	acpi_smbus_register_callback(sbs->hc, acpi_sbs_callback, sbs);
677       end:
678 	if (result)
679 		acpi_sbs_remove(device);
680 	return result;
681 }
682 
683 static int acpi_sbs_remove(struct acpi_device *device)
684 {
685 	struct acpi_sbs *sbs;
686 	int id;
687 
688 	if (!device)
689 		return -EINVAL;
690 	sbs = acpi_driver_data(device);
691 	if (!sbs)
692 		return -EINVAL;
693 	mutex_lock(&sbs->lock);
694 	acpi_smbus_unregister_callback(sbs->hc);
695 	for (id = 0; id < MAX_SBS_BAT; ++id)
696 		acpi_battery_remove(sbs, id);
697 	acpi_charger_remove(sbs);
698 	mutex_unlock(&sbs->lock);
699 	mutex_destroy(&sbs->lock);
700 	kfree(sbs);
701 	return 0;
702 }
703 
704 #ifdef CONFIG_PM_SLEEP
705 static int acpi_sbs_resume(struct device *dev)
706 {
707 	struct acpi_sbs *sbs;
708 	if (!dev)
709 		return -EINVAL;
710 	sbs = to_acpi_device(dev)->driver_data;
711 	acpi_sbs_callback(sbs);
712 	return 0;
713 }
714 #else
715 #define acpi_sbs_resume NULL
716 #endif
717 
718 static SIMPLE_DEV_PM_OPS(acpi_sbs_pm, NULL, acpi_sbs_resume);
719 
720 static struct acpi_driver acpi_sbs_driver = {
721 	.name = "sbs",
722 	.class = ACPI_SBS_CLASS,
723 	.ids = sbs_device_ids,
724 	.ops = {
725 		.add = acpi_sbs_add,
726 		.remove = acpi_sbs_remove,
727 		},
728 	.drv.pm = &acpi_sbs_pm,
729 };
730 
731 static int __init acpi_sbs_init(void)
732 {
733 	int result = 0;
734 
735 	if (acpi_disabled)
736 		return -ENODEV;
737 
738 	result = acpi_bus_register_driver(&acpi_sbs_driver);
739 	if (result < 0)
740 		return -ENODEV;
741 
742 	return 0;
743 }
744 
745 static void __exit acpi_sbs_exit(void)
746 {
747 	acpi_bus_unregister_driver(&acpi_sbs_driver);
748 	return;
749 }
750 
751 module_init(acpi_sbs_init);
752 module_exit(acpi_sbs_exit);
753