xref: /openbmc/linux/drivers/acpi/sbs.c (revision 93df8a1e)
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  *  You should have received a copy of the GNU General Public License along
21  *  with this program; if not, write to the Free Software Foundation, Inc.,
22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  */
26 
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/module.h>
30 #include <linux/moduleparam.h>
31 #include <linux/kernel.h>
32 
33 #include <linux/acpi.h>
34 #include <linux/timer.h>
35 #include <linux/jiffies.h>
36 #include <linux/delay.h>
37 #include <linux/power_supply.h>
38 #include <linux/dmi.h>
39 
40 #include "sbshc.h"
41 #include "battery.h"
42 
43 #define PREFIX "ACPI: "
44 
45 #define ACPI_SBS_CLASS			"sbs"
46 #define ACPI_AC_CLASS			"ac_adapter"
47 #define ACPI_SBS_DEVICE_NAME		"Smart Battery System"
48 #define ACPI_SBS_FILE_INFO		"info"
49 #define ACPI_SBS_FILE_STATE		"state"
50 #define ACPI_SBS_FILE_ALARM		"alarm"
51 #define ACPI_BATTERY_DIR_NAME		"BAT%i"
52 #define ACPI_AC_DIR_NAME		"AC0"
53 
54 #define ACPI_SBS_NOTIFY_STATUS		0x80
55 #define ACPI_SBS_NOTIFY_INFO		0x81
56 
57 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
58 MODULE_DESCRIPTION("Smart Battery System ACPI interface driver");
59 MODULE_LICENSE("GPL");
60 
61 static unsigned int cache_time = 1000;
62 module_param(cache_time, uint, 0644);
63 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
64 
65 static bool sbs_manager_broken;
66 
67 #define MAX_SBS_BAT			4
68 #define ACPI_SBS_BLOCK_MAX		32
69 
70 static const struct acpi_device_id sbs_device_ids[] = {
71 	{"ACPI0002", 0},
72 	{"", 0},
73 };
74 MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
75 
76 struct acpi_battery {
77 	struct power_supply *bat;
78 	struct power_supply_desc bat_desc;
79 	struct acpi_sbs *sbs;
80 	unsigned long update_time;
81 	char name[8];
82 	char manufacturer_name[ACPI_SBS_BLOCK_MAX];
83 	char device_name[ACPI_SBS_BLOCK_MAX];
84 	char device_chemistry[ACPI_SBS_BLOCK_MAX];
85 	u16 alarm_capacity;
86 	u16 full_charge_capacity;
87 	u16 design_capacity;
88 	u16 design_voltage;
89 	u16 serial_number;
90 	u16 cycle_count;
91 	u16 temp_now;
92 	u16 voltage_now;
93 	s16 rate_now;
94 	s16 rate_avg;
95 	u16 capacity_now;
96 	u16 state_of_charge;
97 	u16 state;
98 	u16 mode;
99 	u16 spec;
100 	u8 id;
101 	u8 present:1;
102 	u8 have_sysfs_alarm:1;
103 };
104 
105 #define to_acpi_battery(x) power_supply_get_drvdata(x)
106 
107 struct acpi_sbs {
108 	struct power_supply *charger;
109 	struct acpi_device *device;
110 	struct acpi_smb_hc *hc;
111 	struct mutex lock;
112 	struct acpi_battery battery[MAX_SBS_BAT];
113 	u8 batteries_supported:4;
114 	u8 manager_present:1;
115 	u8 charger_present:1;
116 	u8 charger_exists:1;
117 };
118 
119 #define to_acpi_sbs(x) power_supply_get_drvdata(x)
120 
121 static int acpi_sbs_remove(struct acpi_device *device);
122 static int acpi_battery_get_state(struct acpi_battery *battery);
123 
124 static inline int battery_scale(int log)
125 {
126 	int scale = 1;
127 	while (log--)
128 		scale *= 10;
129 	return scale;
130 }
131 
132 static inline int acpi_battery_vscale(struct acpi_battery *battery)
133 {
134 	return battery_scale((battery->spec & 0x0f00) >> 8);
135 }
136 
137 static inline int acpi_battery_ipscale(struct acpi_battery *battery)
138 {
139 	return battery_scale((battery->spec & 0xf000) >> 12);
140 }
141 
142 static inline int acpi_battery_mode(struct acpi_battery *battery)
143 {
144 	return (battery->mode & 0x8000);
145 }
146 
147 static inline int acpi_battery_scale(struct acpi_battery *battery)
148 {
149 	return (acpi_battery_mode(battery) ? 10 : 1) *
150 	    acpi_battery_ipscale(battery);
151 }
152 
153 static int sbs_get_ac_property(struct power_supply *psy,
154 			       enum power_supply_property psp,
155 			       union power_supply_propval *val)
156 {
157 	struct acpi_sbs *sbs = to_acpi_sbs(psy);
158 	switch (psp) {
159 	case POWER_SUPPLY_PROP_ONLINE:
160 		val->intval = sbs->charger_present;
161 		break;
162 	default:
163 		return -EINVAL;
164 	}
165 	return 0;
166 }
167 
168 static int acpi_battery_technology(struct acpi_battery *battery)
169 {
170 	if (!strcasecmp("NiCd", battery->device_chemistry))
171 		return POWER_SUPPLY_TECHNOLOGY_NiCd;
172 	if (!strcasecmp("NiMH", battery->device_chemistry))
173 		return POWER_SUPPLY_TECHNOLOGY_NiMH;
174 	if (!strcasecmp("LION", battery->device_chemistry))
175 		return POWER_SUPPLY_TECHNOLOGY_LION;
176 	if (!strcasecmp("LiP", battery->device_chemistry))
177 		return POWER_SUPPLY_TECHNOLOGY_LIPO;
178 	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
179 }
180 
181 static int acpi_sbs_battery_get_property(struct power_supply *psy,
182 					 enum power_supply_property psp,
183 					 union power_supply_propval *val)
184 {
185 	struct acpi_battery *battery = to_acpi_battery(psy);
186 
187 	if ((!battery->present) && psp != POWER_SUPPLY_PROP_PRESENT)
188 		return -ENODEV;
189 
190 	acpi_battery_get_state(battery);
191 	switch (psp) {
192 	case POWER_SUPPLY_PROP_STATUS:
193 		if (battery->rate_now < 0)
194 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
195 		else if (battery->rate_now > 0)
196 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
197 		else
198 			val->intval = POWER_SUPPLY_STATUS_FULL;
199 		break;
200 	case POWER_SUPPLY_PROP_PRESENT:
201 		val->intval = battery->present;
202 		break;
203 	case POWER_SUPPLY_PROP_TECHNOLOGY:
204 		val->intval = acpi_battery_technology(battery);
205 		break;
206 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
207 		val->intval = battery->cycle_count;
208 		break;
209 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
210 		val->intval = battery->design_voltage *
211 			acpi_battery_vscale(battery) * 1000;
212 		break;
213 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
214 		val->intval = battery->voltage_now *
215 				acpi_battery_vscale(battery) * 1000;
216 		break;
217 	case POWER_SUPPLY_PROP_CURRENT_NOW:
218 	case POWER_SUPPLY_PROP_POWER_NOW:
219 		val->intval = abs(battery->rate_now) *
220 				acpi_battery_ipscale(battery) * 1000;
221 		val->intval *= (acpi_battery_mode(battery)) ?
222 				(battery->voltage_now *
223 				acpi_battery_vscale(battery) / 1000) : 1;
224 		break;
225 	case POWER_SUPPLY_PROP_CURRENT_AVG:
226 	case POWER_SUPPLY_PROP_POWER_AVG:
227 		val->intval = abs(battery->rate_avg) *
228 				acpi_battery_ipscale(battery) * 1000;
229 		val->intval *= (acpi_battery_mode(battery)) ?
230 				(battery->voltage_now *
231 				acpi_battery_vscale(battery) / 1000) : 1;
232 		break;
233 	case POWER_SUPPLY_PROP_CAPACITY:
234 		val->intval = battery->state_of_charge;
235 		break;
236 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
237 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
238 		val->intval = battery->design_capacity *
239 			acpi_battery_scale(battery) * 1000;
240 		break;
241 	case POWER_SUPPLY_PROP_CHARGE_FULL:
242 	case POWER_SUPPLY_PROP_ENERGY_FULL:
243 		val->intval = battery->full_charge_capacity *
244 			acpi_battery_scale(battery) * 1000;
245 		break;
246 	case POWER_SUPPLY_PROP_CHARGE_NOW:
247 	case POWER_SUPPLY_PROP_ENERGY_NOW:
248 		val->intval = battery->capacity_now *
249 				acpi_battery_scale(battery) * 1000;
250 		break;
251 	case POWER_SUPPLY_PROP_TEMP:
252 		val->intval = battery->temp_now - 2730;	// dK -> dC
253 		break;
254 	case POWER_SUPPLY_PROP_MODEL_NAME:
255 		val->strval = battery->device_name;
256 		break;
257 	case POWER_SUPPLY_PROP_MANUFACTURER:
258 		val->strval = battery->manufacturer_name;
259 		break;
260 	default:
261 		return -EINVAL;
262 	}
263 	return 0;
264 }
265 
266 static enum power_supply_property sbs_ac_props[] = {
267 	POWER_SUPPLY_PROP_ONLINE,
268 };
269 
270 static enum power_supply_property sbs_charge_battery_props[] = {
271 	POWER_SUPPLY_PROP_STATUS,
272 	POWER_SUPPLY_PROP_PRESENT,
273 	POWER_SUPPLY_PROP_TECHNOLOGY,
274 	POWER_SUPPLY_PROP_CYCLE_COUNT,
275 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
276 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
277 	POWER_SUPPLY_PROP_CURRENT_NOW,
278 	POWER_SUPPLY_PROP_CURRENT_AVG,
279 	POWER_SUPPLY_PROP_CAPACITY,
280 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
281 	POWER_SUPPLY_PROP_CHARGE_FULL,
282 	POWER_SUPPLY_PROP_CHARGE_NOW,
283 	POWER_SUPPLY_PROP_TEMP,
284 	POWER_SUPPLY_PROP_MODEL_NAME,
285 	POWER_SUPPLY_PROP_MANUFACTURER,
286 };
287 
288 static enum power_supply_property sbs_energy_battery_props[] = {
289 	POWER_SUPPLY_PROP_STATUS,
290 	POWER_SUPPLY_PROP_PRESENT,
291 	POWER_SUPPLY_PROP_TECHNOLOGY,
292 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
293 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
294 	POWER_SUPPLY_PROP_CURRENT_NOW,
295 	POWER_SUPPLY_PROP_CURRENT_AVG,
296 	POWER_SUPPLY_PROP_POWER_NOW,
297 	POWER_SUPPLY_PROP_POWER_AVG,
298 	POWER_SUPPLY_PROP_CAPACITY,
299 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
300 	POWER_SUPPLY_PROP_ENERGY_FULL,
301 	POWER_SUPPLY_PROP_ENERGY_NOW,
302 	POWER_SUPPLY_PROP_TEMP,
303 	POWER_SUPPLY_PROP_MODEL_NAME,
304 	POWER_SUPPLY_PROP_MANUFACTURER,
305 };
306 
307 static const struct power_supply_desc acpi_sbs_charger_desc = {
308 	.name		= "sbs-charger",
309 	.type		= POWER_SUPPLY_TYPE_MAINS,
310 	.properties	= sbs_ac_props,
311 	.num_properties	= ARRAY_SIZE(sbs_ac_props),
312 	.get_property	= sbs_get_ac_property,
313 };
314 
315 /* --------------------------------------------------------------------------
316                             Smart Battery System Management
317    -------------------------------------------------------------------------- */
318 
319 struct acpi_battery_reader {
320 	u8 command;		/* command for battery */
321 	u8 mode;		/* word or block? */
322 	size_t offset;		/* offset inside struct acpi_sbs_battery */
323 };
324 
325 static struct acpi_battery_reader info_readers[] = {
326 	{0x01, SMBUS_READ_WORD, offsetof(struct acpi_battery, alarm_capacity)},
327 	{0x03, SMBUS_READ_WORD, offsetof(struct acpi_battery, mode)},
328 	{0x10, SMBUS_READ_WORD, offsetof(struct acpi_battery, full_charge_capacity)},
329 	{0x17, SMBUS_READ_WORD, offsetof(struct acpi_battery, cycle_count)},
330 	{0x18, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_capacity)},
331 	{0x19, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_voltage)},
332 	{0x1a, SMBUS_READ_WORD, offsetof(struct acpi_battery, spec)},
333 	{0x1c, SMBUS_READ_WORD, offsetof(struct acpi_battery, serial_number)},
334 	{0x20, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, manufacturer_name)},
335 	{0x21, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_name)},
336 	{0x22, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_chemistry)},
337 };
338 
339 static struct acpi_battery_reader state_readers[] = {
340 	{0x08, SMBUS_READ_WORD, offsetof(struct acpi_battery, temp_now)},
341 	{0x09, SMBUS_READ_WORD, offsetof(struct acpi_battery, voltage_now)},
342 	{0x0a, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_now)},
343 	{0x0b, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_avg)},
344 	{0x0f, SMBUS_READ_WORD, offsetof(struct acpi_battery, capacity_now)},
345 	{0x0e, SMBUS_READ_WORD, offsetof(struct acpi_battery, state_of_charge)},
346 	{0x16, SMBUS_READ_WORD, offsetof(struct acpi_battery, state)},
347 };
348 
349 static int acpi_manager_get_info(struct acpi_sbs *sbs)
350 {
351 	int result = 0;
352 	u16 battery_system_info;
353 
354 	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,
355 				 0x04, (u8 *)&battery_system_info);
356 	if (!result)
357 		sbs->batteries_supported = battery_system_info & 0x000f;
358 	return result;
359 }
360 
361 static int acpi_battery_get_info(struct acpi_battery *battery)
362 {
363 	int i, result = 0;
364 
365 	for (i = 0; i < ARRAY_SIZE(info_readers); ++i) {
366 		result = acpi_smbus_read(battery->sbs->hc,
367 					 info_readers[i].mode,
368 					 ACPI_SBS_BATTERY,
369 					 info_readers[i].command,
370 					 (u8 *) battery +
371 						info_readers[i].offset);
372 		if (result)
373 			break;
374 	}
375 	return result;
376 }
377 
378 static int acpi_battery_get_state(struct acpi_battery *battery)
379 {
380 	int i, result = 0;
381 
382 	if (battery->update_time &&
383 	    time_before(jiffies, battery->update_time +
384 				msecs_to_jiffies(cache_time)))
385 		return 0;
386 	for (i = 0; i < ARRAY_SIZE(state_readers); ++i) {
387 		result = acpi_smbus_read(battery->sbs->hc,
388 					 state_readers[i].mode,
389 					 ACPI_SBS_BATTERY,
390 					 state_readers[i].command,
391 				         (u8 *)battery +
392 						state_readers[i].offset);
393 		if (result)
394 			goto end;
395 	}
396       end:
397 	battery->update_time = jiffies;
398 	return result;
399 }
400 
401 static int acpi_battery_get_alarm(struct acpi_battery *battery)
402 {
403 	return acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
404 				 ACPI_SBS_BATTERY, 0x01,
405 				 (u8 *)&battery->alarm_capacity);
406 }
407 
408 static int acpi_battery_set_alarm(struct acpi_battery *battery)
409 {
410 	struct acpi_sbs *sbs = battery->sbs;
411 	u16 value, sel = 1 << (battery->id + 12);
412 
413 	int ret;
414 
415 
416 	if (sbs->manager_present) {
417 		ret = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,
418 				0x01, (u8 *)&value);
419 		if (ret)
420 			goto end;
421 		if ((value & 0xf000) != sel) {
422 			value &= 0x0fff;
423 			value |= sel;
424 		ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD,
425 					 ACPI_SBS_MANAGER,
426 					 0x01, (u8 *)&value, 2);
427 		if (ret)
428 			goto end;
429 		}
430 	}
431 	ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD, ACPI_SBS_BATTERY,
432 				0x01, (u8 *)&battery->alarm_capacity, 2);
433       end:
434 	return ret;
435 }
436 
437 static int acpi_ac_get_present(struct acpi_sbs *sbs)
438 {
439 	int result;
440 	u16 status;
441 
442 	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_CHARGER,
443 				 0x13, (u8 *) & status);
444 
445 	if (result)
446 		return result;
447 
448 	/*
449 	 * The spec requires that bit 4 always be 1. If it's not set, assume
450 	 * that the implementation doesn't support an SBS charger
451 	 */
452 	if (!((status >> 4) & 0x1))
453 		return -ENODEV;
454 
455 	sbs->charger_present = (status >> 15) & 0x1;
456 	return 0;
457 }
458 
459 static ssize_t acpi_battery_alarm_show(struct device *dev,
460 					struct device_attribute *attr,
461 					char *buf)
462 {
463 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
464 	acpi_battery_get_alarm(battery);
465 	return sprintf(buf, "%d\n", battery->alarm_capacity *
466 				acpi_battery_scale(battery) * 1000);
467 }
468 
469 static ssize_t acpi_battery_alarm_store(struct device *dev,
470 					struct device_attribute *attr,
471 					const char *buf, size_t count)
472 {
473 	unsigned long x;
474 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
475 	if (sscanf(buf, "%lu\n", &x) == 1)
476 		battery->alarm_capacity = x /
477 			(1000 * acpi_battery_scale(battery));
478 	if (battery->present)
479 		acpi_battery_set_alarm(battery);
480 	return count;
481 }
482 
483 static struct device_attribute alarm_attr = {
484 	.attr = {.name = "alarm", .mode = 0644},
485 	.show = acpi_battery_alarm_show,
486 	.store = acpi_battery_alarm_store,
487 };
488 
489 /* --------------------------------------------------------------------------
490                                  Driver Interface
491    -------------------------------------------------------------------------- */
492 static int acpi_battery_read(struct acpi_battery *battery)
493 {
494 	int result = 0, saved_present = battery->present;
495 	u16 state;
496 
497 	if (battery->sbs->manager_present) {
498 		result = acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
499 				ACPI_SBS_MANAGER, 0x01, (u8 *)&state);
500 		if (!result)
501 			battery->present = state & (1 << battery->id);
502 		state &= 0x0fff;
503 		state |= 1 << (battery->id + 12);
504 		acpi_smbus_write(battery->sbs->hc, SMBUS_WRITE_WORD,
505 				  ACPI_SBS_MANAGER, 0x01, (u8 *)&state, 2);
506 	} else if (battery->id == 0)
507 		battery->present = 1;
508 
509 	if (result || !battery->present)
510 		return result;
511 
512 	if (saved_present != battery->present) {
513 		battery->update_time = 0;
514 		result = acpi_battery_get_info(battery);
515 		if (result) {
516 			battery->present = 0;
517 			return result;
518 		}
519 	}
520 	result = acpi_battery_get_state(battery);
521 	if (result)
522 		battery->present = 0;
523 	return result;
524 }
525 
526 /* Smart Battery */
527 static int acpi_battery_add(struct acpi_sbs *sbs, int id)
528 {
529 	struct acpi_battery *battery = &sbs->battery[id];
530 	struct power_supply_config psy_cfg = { .drv_data = battery, };
531 	int result;
532 
533 	battery->id = id;
534 	battery->sbs = sbs;
535 	result = acpi_battery_read(battery);
536 	if (result)
537 		return result;
538 
539 	sprintf(battery->name, ACPI_BATTERY_DIR_NAME, id);
540 	battery->bat_desc.name = battery->name;
541 	battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
542 	if (!acpi_battery_mode(battery)) {
543 		battery->bat_desc.properties = sbs_charge_battery_props;
544 		battery->bat_desc.num_properties =
545 		    ARRAY_SIZE(sbs_charge_battery_props);
546 	} else {
547 		battery->bat_desc.properties = sbs_energy_battery_props;
548 		battery->bat_desc.num_properties =
549 		    ARRAY_SIZE(sbs_energy_battery_props);
550 	}
551 	battery->bat_desc.get_property = acpi_sbs_battery_get_property;
552 	battery->bat = power_supply_register(&sbs->device->dev,
553 					&battery->bat_desc, &psy_cfg);
554 	if (IS_ERR(battery->bat)) {
555 		result = PTR_ERR(battery->bat);
556 		battery->bat = NULL;
557 		goto end;
558 	}
559 
560 	result = device_create_file(&battery->bat->dev, &alarm_attr);
561 	if (result)
562 		goto end;
563 	battery->have_sysfs_alarm = 1;
564       end:
565 	printk(KERN_INFO PREFIX "%s [%s]: Battery Slot [%s] (battery %s)\n",
566 	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
567 	       battery->name, battery->present ? "present" : "absent");
568 	return result;
569 }
570 
571 static void acpi_battery_remove(struct acpi_sbs *sbs, int id)
572 {
573 	struct acpi_battery *battery = &sbs->battery[id];
574 
575 	if (battery->bat) {
576 		if (battery->have_sysfs_alarm)
577 			device_remove_file(&battery->bat->dev, &alarm_attr);
578 		power_supply_unregister(battery->bat);
579 	}
580 }
581 
582 static int acpi_charger_add(struct acpi_sbs *sbs)
583 {
584 	int result;
585 	struct power_supply_config psy_cfg = { .drv_data = sbs, };
586 
587 	result = acpi_ac_get_present(sbs);
588 	if (result)
589 		goto end;
590 
591 	sbs->charger_exists = 1;
592 	sbs->charger = power_supply_register(&sbs->device->dev,
593 					&acpi_sbs_charger_desc, &psy_cfg);
594 	if (IS_ERR(sbs->charger)) {
595 		result = PTR_ERR(sbs->charger);
596 		sbs->charger = NULL;
597 	}
598 	printk(KERN_INFO PREFIX "%s [%s]: AC Adapter [%s] (%s)\n",
599 	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
600 	       ACPI_AC_DIR_NAME, sbs->charger_present ? "on-line" : "off-line");
601       end:
602 	return result;
603 }
604 
605 static void acpi_charger_remove(struct acpi_sbs *sbs)
606 {
607 	if (sbs->charger)
608 		power_supply_unregister(sbs->charger);
609 }
610 
611 static void acpi_sbs_callback(void *context)
612 {
613 	int id;
614 	struct acpi_sbs *sbs = context;
615 	struct acpi_battery *bat;
616 	u8 saved_charger_state = sbs->charger_present;
617 	u8 saved_battery_state;
618 
619 	if (sbs->charger_exists) {
620 		acpi_ac_get_present(sbs);
621 		if (sbs->charger_present != saved_charger_state)
622 			kobject_uevent(&sbs->charger->dev.kobj, KOBJ_CHANGE);
623 	}
624 
625 	if (sbs->manager_present) {
626 		for (id = 0; id < MAX_SBS_BAT; ++id) {
627 			if (!(sbs->batteries_supported & (1 << id)))
628 				continue;
629 			bat = &sbs->battery[id];
630 			saved_battery_state = bat->present;
631 			acpi_battery_read(bat);
632 			if (saved_battery_state == bat->present)
633 				continue;
634 			kobject_uevent(&bat->bat->dev.kobj, KOBJ_CHANGE);
635 		}
636 	}
637 }
638 
639 static int disable_sbs_manager(const struct dmi_system_id *d)
640 {
641 	sbs_manager_broken = true;
642 	return 0;
643 }
644 
645 static struct dmi_system_id acpi_sbs_dmi_table[] = {
646 	{
647 		.callback = disable_sbs_manager,
648 		.ident = "Apple",
649 		.matches = {
650 			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc.")
651 		},
652 	},
653 	{ },
654 };
655 
656 static int acpi_sbs_add(struct acpi_device *device)
657 {
658 	struct acpi_sbs *sbs;
659 	int result = 0;
660 	int id;
661 
662 	dmi_check_system(acpi_sbs_dmi_table);
663 
664 	sbs = kzalloc(sizeof(struct acpi_sbs), GFP_KERNEL);
665 	if (!sbs) {
666 		result = -ENOMEM;
667 		goto end;
668 	}
669 
670 	mutex_init(&sbs->lock);
671 
672 	sbs->hc = acpi_driver_data(device->parent);
673 	sbs->device = device;
674 	strcpy(acpi_device_name(device), ACPI_SBS_DEVICE_NAME);
675 	strcpy(acpi_device_class(device), ACPI_SBS_CLASS);
676 	device->driver_data = sbs;
677 
678 	result = acpi_charger_add(sbs);
679 	if (result && result != -ENODEV)
680 		goto end;
681 
682 	result = 0;
683 
684 	if (!sbs_manager_broken) {
685 		result = acpi_manager_get_info(sbs);
686 		if (!result) {
687 			sbs->manager_present = 1;
688 			for (id = 0; id < MAX_SBS_BAT; ++id)
689 				if ((sbs->batteries_supported & (1 << id)))
690 					acpi_battery_add(sbs, id);
691 		}
692 	}
693 
694 	if (!sbs->manager_present)
695 		acpi_battery_add(sbs, 0);
696 
697 	acpi_smbus_register_callback(sbs->hc, acpi_sbs_callback, sbs);
698       end:
699 	if (result)
700 		acpi_sbs_remove(device);
701 	return result;
702 }
703 
704 static int acpi_sbs_remove(struct acpi_device *device)
705 {
706 	struct acpi_sbs *sbs;
707 	int id;
708 
709 	if (!device)
710 		return -EINVAL;
711 	sbs = acpi_driver_data(device);
712 	if (!sbs)
713 		return -EINVAL;
714 	mutex_lock(&sbs->lock);
715 	acpi_smbus_unregister_callback(sbs->hc);
716 	for (id = 0; id < MAX_SBS_BAT; ++id)
717 		acpi_battery_remove(sbs, id);
718 	acpi_charger_remove(sbs);
719 	mutex_unlock(&sbs->lock);
720 	mutex_destroy(&sbs->lock);
721 	kfree(sbs);
722 	return 0;
723 }
724 
725 #ifdef CONFIG_PM_SLEEP
726 static int acpi_sbs_resume(struct device *dev)
727 {
728 	struct acpi_sbs *sbs;
729 	if (!dev)
730 		return -EINVAL;
731 	sbs = to_acpi_device(dev)->driver_data;
732 	acpi_sbs_callback(sbs);
733 	return 0;
734 }
735 #else
736 #define acpi_sbs_resume NULL
737 #endif
738 
739 static SIMPLE_DEV_PM_OPS(acpi_sbs_pm, NULL, acpi_sbs_resume);
740 
741 static struct acpi_driver acpi_sbs_driver = {
742 	.name = "sbs",
743 	.class = ACPI_SBS_CLASS,
744 	.ids = sbs_device_ids,
745 	.ops = {
746 		.add = acpi_sbs_add,
747 		.remove = acpi_sbs_remove,
748 		},
749 	.drv.pm = &acpi_sbs_pm,
750 };
751 
752 static int __init acpi_sbs_init(void)
753 {
754 	int result = 0;
755 
756 	if (acpi_disabled)
757 		return -ENODEV;
758 
759 	result = acpi_bus_register_driver(&acpi_sbs_driver);
760 	if (result < 0)
761 		return -ENODEV;
762 
763 	return 0;
764 }
765 
766 static void __exit acpi_sbs_exit(void)
767 {
768 	acpi_bus_unregister_driver(&acpi_sbs_driver);
769 	return;
770 }
771 
772 module_init(acpi_sbs_init);
773 module_exit(acpi_sbs_exit);
774