xref: /openbmc/linux/drivers/acpi/sbs.c (revision 3a35093a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  sbs.c - ACPI Smart Battery System Driver ($Revision: 2.0 $)
4  *
5  *  Copyright (c) 2007 Alexey Starikovskiy <astarikovskiy@suse.de>
6  *  Copyright (c) 2005-2007 Vladimir Lebedev <vladimir.p.lebedev@intel.com>
7  *  Copyright (c) 2005 Rich Townsend <rhdt@bartol.udel.edu>
8  */
9 
10 #include <linux/init.h>
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/moduleparam.h>
14 #include <linux/kernel.h>
15 
16 #include <linux/acpi.h>
17 #include <linux/timer.h>
18 #include <linux/jiffies.h>
19 #include <linux/delay.h>
20 #include <linux/power_supply.h>
21 #include <linux/platform_data/x86/apple.h>
22 #include <acpi/battery.h>
23 
24 #include "sbshc.h"
25 
26 #define PREFIX "ACPI: "
27 
28 #define ACPI_SBS_CLASS			"sbs"
29 #define ACPI_AC_CLASS			"ac_adapter"
30 #define ACPI_SBS_DEVICE_NAME		"Smart Battery System"
31 #define ACPI_BATTERY_DIR_NAME		"BAT%i"
32 #define ACPI_AC_DIR_NAME		"AC0"
33 
34 #define ACPI_SBS_NOTIFY_STATUS		0x80
35 #define ACPI_SBS_NOTIFY_INFO		0x81
36 
37 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
38 MODULE_DESCRIPTION("Smart Battery System ACPI interface driver");
39 MODULE_LICENSE("GPL");
40 
41 static unsigned int cache_time = 1000;
42 module_param(cache_time, uint, 0644);
43 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
44 
45 #define MAX_SBS_BAT			4
46 #define ACPI_SBS_BLOCK_MAX		32
47 
48 static const struct acpi_device_id sbs_device_ids[] = {
49 	{"ACPI0002", 0},
50 	{"", 0},
51 };
52 MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
53 
54 struct acpi_battery {
55 	struct power_supply *bat;
56 	struct power_supply_desc bat_desc;
57 	struct acpi_sbs *sbs;
58 	unsigned long update_time;
59 	char name[8];
60 	char manufacturer_name[ACPI_SBS_BLOCK_MAX];
61 	char device_name[ACPI_SBS_BLOCK_MAX];
62 	char device_chemistry[ACPI_SBS_BLOCK_MAX];
63 	u16 alarm_capacity;
64 	u16 full_charge_capacity;
65 	u16 design_capacity;
66 	u16 design_voltage;
67 	u16 serial_number;
68 	u16 cycle_count;
69 	u16 temp_now;
70 	u16 voltage_now;
71 	s16 rate_now;
72 	s16 rate_avg;
73 	u16 capacity_now;
74 	u16 state_of_charge;
75 	u16 state;
76 	u16 mode;
77 	u16 spec;
78 	u8 id;
79 	u8 present:1;
80 	u8 have_sysfs_alarm:1;
81 };
82 
83 #define to_acpi_battery(x) power_supply_get_drvdata(x)
84 
85 struct acpi_sbs {
86 	struct power_supply *charger;
87 	struct acpi_device *device;
88 	struct acpi_smb_hc *hc;
89 	struct mutex lock;
90 	struct acpi_battery battery[MAX_SBS_BAT];
91 	u8 batteries_supported:4;
92 	u8 manager_present:1;
93 	u8 charger_present:1;
94 	u8 charger_exists:1;
95 };
96 
97 #define to_acpi_sbs(x) power_supply_get_drvdata(x)
98 
99 static int acpi_sbs_remove(struct acpi_device *device);
100 static int acpi_battery_get_state(struct acpi_battery *battery);
101 
102 static inline int battery_scale(int log)
103 {
104 	int scale = 1;
105 	while (log--)
106 		scale *= 10;
107 	return scale;
108 }
109 
110 static inline int acpi_battery_vscale(struct acpi_battery *battery)
111 {
112 	return battery_scale((battery->spec & 0x0f00) >> 8);
113 }
114 
115 static inline int acpi_battery_ipscale(struct acpi_battery *battery)
116 {
117 	return battery_scale((battery->spec & 0xf000) >> 12);
118 }
119 
120 static inline int acpi_battery_mode(struct acpi_battery *battery)
121 {
122 	return (battery->mode & 0x8000);
123 }
124 
125 static inline int acpi_battery_scale(struct acpi_battery *battery)
126 {
127 	return (acpi_battery_mode(battery) ? 10 : 1) *
128 	    acpi_battery_ipscale(battery);
129 }
130 
131 static int sbs_get_ac_property(struct power_supply *psy,
132 			       enum power_supply_property psp,
133 			       union power_supply_propval *val)
134 {
135 	struct acpi_sbs *sbs = to_acpi_sbs(psy);
136 	switch (psp) {
137 	case POWER_SUPPLY_PROP_ONLINE:
138 		val->intval = sbs->charger_present;
139 		break;
140 	default:
141 		return -EINVAL;
142 	}
143 	return 0;
144 }
145 
146 static int acpi_battery_technology(struct acpi_battery *battery)
147 {
148 	if (!strcasecmp("NiCd", battery->device_chemistry))
149 		return POWER_SUPPLY_TECHNOLOGY_NiCd;
150 	if (!strcasecmp("NiMH", battery->device_chemistry))
151 		return POWER_SUPPLY_TECHNOLOGY_NiMH;
152 	if (!strcasecmp("LION", battery->device_chemistry))
153 		return POWER_SUPPLY_TECHNOLOGY_LION;
154 	if (!strcasecmp("LiP", battery->device_chemistry))
155 		return POWER_SUPPLY_TECHNOLOGY_LIPO;
156 	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
157 }
158 
159 static int acpi_sbs_battery_get_property(struct power_supply *psy,
160 					 enum power_supply_property psp,
161 					 union power_supply_propval *val)
162 {
163 	struct acpi_battery *battery = to_acpi_battery(psy);
164 
165 	if ((!battery->present) && psp != POWER_SUPPLY_PROP_PRESENT)
166 		return -ENODEV;
167 
168 	acpi_battery_get_state(battery);
169 	switch (psp) {
170 	case POWER_SUPPLY_PROP_STATUS:
171 		if (battery->rate_now < 0)
172 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
173 		else if (battery->rate_now > 0)
174 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
175 		else
176 			val->intval = POWER_SUPPLY_STATUS_FULL;
177 		break;
178 	case POWER_SUPPLY_PROP_PRESENT:
179 		val->intval = battery->present;
180 		break;
181 	case POWER_SUPPLY_PROP_TECHNOLOGY:
182 		val->intval = acpi_battery_technology(battery);
183 		break;
184 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
185 		val->intval = battery->cycle_count;
186 		break;
187 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
188 		val->intval = battery->design_voltage *
189 			acpi_battery_vscale(battery) * 1000;
190 		break;
191 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
192 		val->intval = battery->voltage_now *
193 				acpi_battery_vscale(battery) * 1000;
194 		break;
195 	case POWER_SUPPLY_PROP_CURRENT_NOW:
196 	case POWER_SUPPLY_PROP_POWER_NOW:
197 		val->intval = abs(battery->rate_now) *
198 				acpi_battery_ipscale(battery) * 1000;
199 		val->intval *= (acpi_battery_mode(battery)) ?
200 				(battery->voltage_now *
201 				acpi_battery_vscale(battery) / 1000) : 1;
202 		break;
203 	case POWER_SUPPLY_PROP_CURRENT_AVG:
204 	case POWER_SUPPLY_PROP_POWER_AVG:
205 		val->intval = abs(battery->rate_avg) *
206 				acpi_battery_ipscale(battery) * 1000;
207 		val->intval *= (acpi_battery_mode(battery)) ?
208 				(battery->voltage_now *
209 				acpi_battery_vscale(battery) / 1000) : 1;
210 		break;
211 	case POWER_SUPPLY_PROP_CAPACITY:
212 		val->intval = battery->state_of_charge;
213 		break;
214 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
215 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
216 		val->intval = battery->design_capacity *
217 			acpi_battery_scale(battery) * 1000;
218 		break;
219 	case POWER_SUPPLY_PROP_CHARGE_FULL:
220 	case POWER_SUPPLY_PROP_ENERGY_FULL:
221 		val->intval = battery->full_charge_capacity *
222 			acpi_battery_scale(battery) * 1000;
223 		break;
224 	case POWER_SUPPLY_PROP_CHARGE_NOW:
225 	case POWER_SUPPLY_PROP_ENERGY_NOW:
226 		val->intval = battery->capacity_now *
227 				acpi_battery_scale(battery) * 1000;
228 		break;
229 	case POWER_SUPPLY_PROP_TEMP:
230 		val->intval = battery->temp_now - 2730;	// dK -> dC
231 		break;
232 	case POWER_SUPPLY_PROP_MODEL_NAME:
233 		val->strval = battery->device_name;
234 		break;
235 	case POWER_SUPPLY_PROP_MANUFACTURER:
236 		val->strval = battery->manufacturer_name;
237 		break;
238 	default:
239 		return -EINVAL;
240 	}
241 	return 0;
242 }
243 
244 static enum power_supply_property sbs_ac_props[] = {
245 	POWER_SUPPLY_PROP_ONLINE,
246 };
247 
248 static enum power_supply_property sbs_charge_battery_props[] = {
249 	POWER_SUPPLY_PROP_STATUS,
250 	POWER_SUPPLY_PROP_PRESENT,
251 	POWER_SUPPLY_PROP_TECHNOLOGY,
252 	POWER_SUPPLY_PROP_CYCLE_COUNT,
253 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
254 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
255 	POWER_SUPPLY_PROP_CURRENT_NOW,
256 	POWER_SUPPLY_PROP_CURRENT_AVG,
257 	POWER_SUPPLY_PROP_CAPACITY,
258 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
259 	POWER_SUPPLY_PROP_CHARGE_FULL,
260 	POWER_SUPPLY_PROP_CHARGE_NOW,
261 	POWER_SUPPLY_PROP_TEMP,
262 	POWER_SUPPLY_PROP_MODEL_NAME,
263 	POWER_SUPPLY_PROP_MANUFACTURER,
264 };
265 
266 static enum power_supply_property sbs_energy_battery_props[] = {
267 	POWER_SUPPLY_PROP_STATUS,
268 	POWER_SUPPLY_PROP_PRESENT,
269 	POWER_SUPPLY_PROP_TECHNOLOGY,
270 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
271 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
272 	POWER_SUPPLY_PROP_CURRENT_NOW,
273 	POWER_SUPPLY_PROP_CURRENT_AVG,
274 	POWER_SUPPLY_PROP_POWER_NOW,
275 	POWER_SUPPLY_PROP_POWER_AVG,
276 	POWER_SUPPLY_PROP_CAPACITY,
277 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
278 	POWER_SUPPLY_PROP_ENERGY_FULL,
279 	POWER_SUPPLY_PROP_ENERGY_NOW,
280 	POWER_SUPPLY_PROP_TEMP,
281 	POWER_SUPPLY_PROP_MODEL_NAME,
282 	POWER_SUPPLY_PROP_MANUFACTURER,
283 };
284 
285 static const struct power_supply_desc acpi_sbs_charger_desc = {
286 	.name		= "sbs-charger",
287 	.type		= POWER_SUPPLY_TYPE_MAINS,
288 	.properties	= sbs_ac_props,
289 	.num_properties	= ARRAY_SIZE(sbs_ac_props),
290 	.get_property	= sbs_get_ac_property,
291 };
292 
293 /* --------------------------------------------------------------------------
294                             Smart Battery System Management
295    -------------------------------------------------------------------------- */
296 
297 struct acpi_battery_reader {
298 	u8 command;		/* command for battery */
299 	u8 mode;		/* word or block? */
300 	size_t offset;		/* offset inside struct acpi_sbs_battery */
301 };
302 
303 static struct acpi_battery_reader info_readers[] = {
304 	{0x01, SMBUS_READ_WORD, offsetof(struct acpi_battery, alarm_capacity)},
305 	{0x03, SMBUS_READ_WORD, offsetof(struct acpi_battery, mode)},
306 	{0x10, SMBUS_READ_WORD, offsetof(struct acpi_battery, full_charge_capacity)},
307 	{0x17, SMBUS_READ_WORD, offsetof(struct acpi_battery, cycle_count)},
308 	{0x18, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_capacity)},
309 	{0x19, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_voltage)},
310 	{0x1a, SMBUS_READ_WORD, offsetof(struct acpi_battery, spec)},
311 	{0x1c, SMBUS_READ_WORD, offsetof(struct acpi_battery, serial_number)},
312 	{0x20, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, manufacturer_name)},
313 	{0x21, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_name)},
314 	{0x22, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_chemistry)},
315 };
316 
317 static struct acpi_battery_reader state_readers[] = {
318 	{0x08, SMBUS_READ_WORD, offsetof(struct acpi_battery, temp_now)},
319 	{0x09, SMBUS_READ_WORD, offsetof(struct acpi_battery, voltage_now)},
320 	{0x0a, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_now)},
321 	{0x0b, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_avg)},
322 	{0x0f, SMBUS_READ_WORD, offsetof(struct acpi_battery, capacity_now)},
323 	{0x0e, SMBUS_READ_WORD, offsetof(struct acpi_battery, state_of_charge)},
324 	{0x16, SMBUS_READ_WORD, offsetof(struct acpi_battery, state)},
325 };
326 
327 static int acpi_manager_get_info(struct acpi_sbs *sbs)
328 {
329 	int result = 0;
330 	u16 battery_system_info;
331 
332 	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,
333 				 0x04, (u8 *)&battery_system_info);
334 	if (!result)
335 		sbs->batteries_supported = battery_system_info & 0x000f;
336 	return result;
337 }
338 
339 static int acpi_battery_get_info(struct acpi_battery *battery)
340 {
341 	int i, result = 0;
342 
343 	for (i = 0; i < ARRAY_SIZE(info_readers); ++i) {
344 		result = acpi_smbus_read(battery->sbs->hc,
345 					 info_readers[i].mode,
346 					 ACPI_SBS_BATTERY,
347 					 info_readers[i].command,
348 					 (u8 *) battery +
349 						info_readers[i].offset);
350 		if (result)
351 			break;
352 	}
353 	return result;
354 }
355 
356 static int acpi_battery_get_state(struct acpi_battery *battery)
357 {
358 	int i, result = 0;
359 
360 	if (battery->update_time &&
361 	    time_before(jiffies, battery->update_time +
362 				msecs_to_jiffies(cache_time)))
363 		return 0;
364 	for (i = 0; i < ARRAY_SIZE(state_readers); ++i) {
365 		result = acpi_smbus_read(battery->sbs->hc,
366 					 state_readers[i].mode,
367 					 ACPI_SBS_BATTERY,
368 					 state_readers[i].command,
369 					 (u8 *)battery +
370 						state_readers[i].offset);
371 		if (result)
372 			goto end;
373 	}
374       end:
375 	battery->update_time = jiffies;
376 	return result;
377 }
378 
379 static int acpi_battery_get_alarm(struct acpi_battery *battery)
380 {
381 	return acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
382 				 ACPI_SBS_BATTERY, 0x01,
383 				 (u8 *)&battery->alarm_capacity);
384 }
385 
386 static int acpi_battery_set_alarm(struct acpi_battery *battery)
387 {
388 	struct acpi_sbs *sbs = battery->sbs;
389 	u16 value, sel = 1 << (battery->id + 12);
390 
391 	int ret;
392 
393 
394 	if (sbs->manager_present) {
395 		ret = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,
396 				0x01, (u8 *)&value);
397 		if (ret)
398 			goto end;
399 		if ((value & 0xf000) != sel) {
400 			value &= 0x0fff;
401 			value |= sel;
402 			ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD,
403 					 ACPI_SBS_MANAGER,
404 					 0x01, (u8 *)&value, 2);
405 			if (ret)
406 				goto end;
407 		}
408 	}
409 	ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD, ACPI_SBS_BATTERY,
410 				0x01, (u8 *)&battery->alarm_capacity, 2);
411       end:
412 	return ret;
413 }
414 
415 static int acpi_ac_get_present(struct acpi_sbs *sbs)
416 {
417 	int result;
418 	u16 status;
419 
420 	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_CHARGER,
421 				 0x13, (u8 *) & status);
422 
423 	if (result)
424 		return result;
425 
426 	/*
427 	 * The spec requires that bit 4 always be 1. If it's not set, assume
428 	 * that the implementation doesn't support an SBS charger.
429 	 *
430 	 * And on some MacBooks a status of 0xffff is always returned, no
431 	 * matter whether the charger is plugged in or not, which is also
432 	 * wrong, so ignore the SBS charger for those too.
433 	 */
434 	if (!((status >> 4) & 0x1) || status == 0xffff)
435 		return -ENODEV;
436 
437 	sbs->charger_present = (status >> 15) & 0x1;
438 	return 0;
439 }
440 
441 static ssize_t acpi_battery_alarm_show(struct device *dev,
442 					struct device_attribute *attr,
443 					char *buf)
444 {
445 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
446 	acpi_battery_get_alarm(battery);
447 	return sprintf(buf, "%d\n", battery->alarm_capacity *
448 				acpi_battery_scale(battery) * 1000);
449 }
450 
451 static ssize_t acpi_battery_alarm_store(struct device *dev,
452 					struct device_attribute *attr,
453 					const char *buf, size_t count)
454 {
455 	unsigned long x;
456 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
457 	if (sscanf(buf, "%lu\n", &x) == 1)
458 		battery->alarm_capacity = x /
459 			(1000 * acpi_battery_scale(battery));
460 	if (battery->present)
461 		acpi_battery_set_alarm(battery);
462 	return count;
463 }
464 
465 static const struct device_attribute alarm_attr = {
466 	.attr = {.name = "alarm", .mode = 0644},
467 	.show = acpi_battery_alarm_show,
468 	.store = acpi_battery_alarm_store,
469 };
470 
471 /* --------------------------------------------------------------------------
472                                  Driver Interface
473    -------------------------------------------------------------------------- */
474 static int acpi_battery_read(struct acpi_battery *battery)
475 {
476 	int result = 0, saved_present = battery->present;
477 	u16 state;
478 
479 	if (battery->sbs->manager_present) {
480 		result = acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
481 				ACPI_SBS_MANAGER, 0x01, (u8 *)&state);
482 		if (!result)
483 			battery->present = state & (1 << battery->id);
484 		state &= 0x0fff;
485 		state |= 1 << (battery->id + 12);
486 		acpi_smbus_write(battery->sbs->hc, SMBUS_WRITE_WORD,
487 				  ACPI_SBS_MANAGER, 0x01, (u8 *)&state, 2);
488 	} else if (battery->id == 0)
489 		battery->present = 1;
490 
491 	if (result || !battery->present)
492 		return result;
493 
494 	if (saved_present != battery->present) {
495 		battery->update_time = 0;
496 		result = acpi_battery_get_info(battery);
497 		if (result) {
498 			battery->present = 0;
499 			return result;
500 		}
501 	}
502 	result = acpi_battery_get_state(battery);
503 	if (result)
504 		battery->present = 0;
505 	return result;
506 }
507 
508 /* Smart Battery */
509 static int acpi_battery_add(struct acpi_sbs *sbs, int id)
510 {
511 	struct acpi_battery *battery = &sbs->battery[id];
512 	struct power_supply_config psy_cfg = { .drv_data = battery, };
513 	int result;
514 
515 	battery->id = id;
516 	battery->sbs = sbs;
517 	result = acpi_battery_read(battery);
518 	if (result)
519 		return result;
520 
521 	sprintf(battery->name, ACPI_BATTERY_DIR_NAME, id);
522 	battery->bat_desc.name = battery->name;
523 	battery->bat_desc.type = POWER_SUPPLY_TYPE_BATTERY;
524 	if (!acpi_battery_mode(battery)) {
525 		battery->bat_desc.properties = sbs_charge_battery_props;
526 		battery->bat_desc.num_properties =
527 		    ARRAY_SIZE(sbs_charge_battery_props);
528 	} else {
529 		battery->bat_desc.properties = sbs_energy_battery_props;
530 		battery->bat_desc.num_properties =
531 		    ARRAY_SIZE(sbs_energy_battery_props);
532 	}
533 	battery->bat_desc.get_property = acpi_sbs_battery_get_property;
534 	battery->bat = power_supply_register(&sbs->device->dev,
535 					&battery->bat_desc, &psy_cfg);
536 	if (IS_ERR(battery->bat)) {
537 		result = PTR_ERR(battery->bat);
538 		battery->bat = NULL;
539 		goto end;
540 	}
541 
542 	result = device_create_file(&battery->bat->dev, &alarm_attr);
543 	if (result)
544 		goto end;
545 	battery->have_sysfs_alarm = 1;
546       end:
547 	printk(KERN_INFO PREFIX "%s [%s]: Battery Slot [%s] (battery %s)\n",
548 	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
549 	       battery->name, battery->present ? "present" : "absent");
550 	return result;
551 }
552 
553 static void acpi_battery_remove(struct acpi_sbs *sbs, int id)
554 {
555 	struct acpi_battery *battery = &sbs->battery[id];
556 
557 	if (battery->bat) {
558 		if (battery->have_sysfs_alarm)
559 			device_remove_file(&battery->bat->dev, &alarm_attr);
560 		power_supply_unregister(battery->bat);
561 	}
562 }
563 
564 static int acpi_charger_add(struct acpi_sbs *sbs)
565 {
566 	int result;
567 	struct power_supply_config psy_cfg = { .drv_data = sbs, };
568 
569 	result = acpi_ac_get_present(sbs);
570 	if (result)
571 		goto end;
572 
573 	sbs->charger_exists = 1;
574 	sbs->charger = power_supply_register(&sbs->device->dev,
575 					&acpi_sbs_charger_desc, &psy_cfg);
576 	if (IS_ERR(sbs->charger)) {
577 		result = PTR_ERR(sbs->charger);
578 		sbs->charger = NULL;
579 	}
580 	printk(KERN_INFO PREFIX "%s [%s]: AC Adapter [%s] (%s)\n",
581 	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
582 	       ACPI_AC_DIR_NAME, sbs->charger_present ? "on-line" : "off-line");
583       end:
584 	return result;
585 }
586 
587 static void acpi_charger_remove(struct acpi_sbs *sbs)
588 {
589 	if (sbs->charger)
590 		power_supply_unregister(sbs->charger);
591 }
592 
593 static void acpi_sbs_callback(void *context)
594 {
595 	int id;
596 	struct acpi_sbs *sbs = context;
597 	struct acpi_battery *bat;
598 	u8 saved_charger_state = sbs->charger_present;
599 	u8 saved_battery_state;
600 
601 	if (sbs->charger_exists) {
602 		acpi_ac_get_present(sbs);
603 		if (sbs->charger_present != saved_charger_state)
604 			kobject_uevent(&sbs->charger->dev.kobj, KOBJ_CHANGE);
605 	}
606 
607 	if (sbs->manager_present) {
608 		for (id = 0; id < MAX_SBS_BAT; ++id) {
609 			if (!(sbs->batteries_supported & (1 << id)))
610 				continue;
611 			bat = &sbs->battery[id];
612 			saved_battery_state = bat->present;
613 			acpi_battery_read(bat);
614 			if (saved_battery_state == bat->present)
615 				continue;
616 			kobject_uevent(&bat->bat->dev.kobj, KOBJ_CHANGE);
617 		}
618 	}
619 }
620 
621 static int acpi_sbs_add(struct acpi_device *device)
622 {
623 	struct acpi_sbs *sbs;
624 	int result = 0;
625 	int id;
626 
627 	sbs = kzalloc(sizeof(struct acpi_sbs), GFP_KERNEL);
628 	if (!sbs) {
629 		result = -ENOMEM;
630 		goto end;
631 	}
632 
633 	mutex_init(&sbs->lock);
634 
635 	sbs->hc = acpi_driver_data(device->parent);
636 	sbs->device = device;
637 	strcpy(acpi_device_name(device), ACPI_SBS_DEVICE_NAME);
638 	strcpy(acpi_device_class(device), ACPI_SBS_CLASS);
639 	device->driver_data = sbs;
640 
641 	result = acpi_charger_add(sbs);
642 	if (result && result != -ENODEV)
643 		goto end;
644 
645 	result = 0;
646 
647 	if (!x86_apple_machine) {
648 		result = acpi_manager_get_info(sbs);
649 		if (!result) {
650 			sbs->manager_present = 1;
651 			for (id = 0; id < MAX_SBS_BAT; ++id)
652 				if ((sbs->batteries_supported & (1 << id)))
653 					acpi_battery_add(sbs, id);
654 		}
655 	}
656 
657 	if (!sbs->manager_present)
658 		acpi_battery_add(sbs, 0);
659 
660 	acpi_smbus_register_callback(sbs->hc, acpi_sbs_callback, sbs);
661       end:
662 	if (result)
663 		acpi_sbs_remove(device);
664 	return result;
665 }
666 
667 static int acpi_sbs_remove(struct acpi_device *device)
668 {
669 	struct acpi_sbs *sbs;
670 	int id;
671 
672 	if (!device)
673 		return -EINVAL;
674 	sbs = acpi_driver_data(device);
675 	if (!sbs)
676 		return -EINVAL;
677 	mutex_lock(&sbs->lock);
678 	acpi_smbus_unregister_callback(sbs->hc);
679 	for (id = 0; id < MAX_SBS_BAT; ++id)
680 		acpi_battery_remove(sbs, id);
681 	acpi_charger_remove(sbs);
682 	mutex_unlock(&sbs->lock);
683 	mutex_destroy(&sbs->lock);
684 	kfree(sbs);
685 	return 0;
686 }
687 
688 #ifdef CONFIG_PM_SLEEP
689 static int acpi_sbs_resume(struct device *dev)
690 {
691 	struct acpi_sbs *sbs;
692 	if (!dev)
693 		return -EINVAL;
694 	sbs = to_acpi_device(dev)->driver_data;
695 	acpi_sbs_callback(sbs);
696 	return 0;
697 }
698 #else
699 #define acpi_sbs_resume NULL
700 #endif
701 
702 static SIMPLE_DEV_PM_OPS(acpi_sbs_pm, NULL, acpi_sbs_resume);
703 
704 static struct acpi_driver acpi_sbs_driver = {
705 	.name = "sbs",
706 	.class = ACPI_SBS_CLASS,
707 	.ids = sbs_device_ids,
708 	.ops = {
709 		.add = acpi_sbs_add,
710 		.remove = acpi_sbs_remove,
711 		},
712 	.drv.pm = &acpi_sbs_pm,
713 };
714 module_acpi_driver(acpi_sbs_driver);
715