xref: /openbmc/linux/drivers/acpi/sbs.c (revision 310ff2c8)
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 
39 #include "sbshc.h"
40 
41 #define PREFIX "ACPI: "
42 
43 #define ACPI_SBS_CLASS			"sbs"
44 #define ACPI_AC_CLASS			"ac_adapter"
45 #define ACPI_BATTERY_CLASS		"battery"
46 #define ACPI_SBS_DEVICE_NAME		"Smart Battery System"
47 #define ACPI_SBS_FILE_INFO		"info"
48 #define ACPI_SBS_FILE_STATE		"state"
49 #define ACPI_SBS_FILE_ALARM		"alarm"
50 #define ACPI_BATTERY_DIR_NAME		"BAT%i"
51 #define ACPI_AC_DIR_NAME		"AC0"
52 
53 #define ACPI_SBS_NOTIFY_STATUS		0x80
54 #define ACPI_SBS_NOTIFY_INFO		0x81
55 
56 MODULE_AUTHOR("Alexey Starikovskiy <astarikovskiy@suse.de>");
57 MODULE_DESCRIPTION("Smart Battery System ACPI interface driver");
58 MODULE_LICENSE("GPL");
59 
60 static unsigned int cache_time = 1000;
61 module_param(cache_time, uint, 0644);
62 MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
63 
64 #define MAX_SBS_BAT			4
65 #define ACPI_SBS_BLOCK_MAX		32
66 
67 static const struct acpi_device_id sbs_device_ids[] = {
68 	{"ACPI0002", 0},
69 	{"", 0},
70 };
71 MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
72 
73 struct acpi_battery {
74 	struct power_supply bat;
75 	struct acpi_sbs *sbs;
76 	unsigned long update_time;
77 	char name[8];
78 	char manufacturer_name[ACPI_SBS_BLOCK_MAX];
79 	char device_name[ACPI_SBS_BLOCK_MAX];
80 	char device_chemistry[ACPI_SBS_BLOCK_MAX];
81 	u16 alarm_capacity;
82 	u16 full_charge_capacity;
83 	u16 design_capacity;
84 	u16 design_voltage;
85 	u16 serial_number;
86 	u16 cycle_count;
87 	u16 temp_now;
88 	u16 voltage_now;
89 	s16 rate_now;
90 	s16 rate_avg;
91 	u16 capacity_now;
92 	u16 state_of_charge;
93 	u16 state;
94 	u16 mode;
95 	u16 spec;
96 	u8 id;
97 	u8 present:1;
98 	u8 have_sysfs_alarm:1;
99 };
100 
101 #define to_acpi_battery(x) container_of(x, struct acpi_battery, bat)
102 
103 struct acpi_sbs {
104 	struct power_supply charger;
105 	struct acpi_device *device;
106 	struct acpi_smb_hc *hc;
107 	struct mutex lock;
108 	struct acpi_battery battery[MAX_SBS_BAT];
109 	u8 batteries_supported:4;
110 	u8 manager_present:1;
111 	u8 charger_present:1;
112 };
113 
114 #define to_acpi_sbs(x) container_of(x, struct acpi_sbs, charger)
115 
116 static int acpi_sbs_remove(struct acpi_device *device);
117 static int acpi_battery_get_state(struct acpi_battery *battery);
118 
119 static inline int battery_scale(int log)
120 {
121 	int scale = 1;
122 	while (log--)
123 		scale *= 10;
124 	return scale;
125 }
126 
127 static inline int acpi_battery_vscale(struct acpi_battery *battery)
128 {
129 	return battery_scale((battery->spec & 0x0f00) >> 8);
130 }
131 
132 static inline int acpi_battery_ipscale(struct acpi_battery *battery)
133 {
134 	return battery_scale((battery->spec & 0xf000) >> 12);
135 }
136 
137 static inline int acpi_battery_mode(struct acpi_battery *battery)
138 {
139 	return (battery->mode & 0x8000);
140 }
141 
142 static inline int acpi_battery_scale(struct acpi_battery *battery)
143 {
144 	return (acpi_battery_mode(battery) ? 10 : 1) *
145 	    acpi_battery_ipscale(battery);
146 }
147 
148 static int sbs_get_ac_property(struct power_supply *psy,
149 			       enum power_supply_property psp,
150 			       union power_supply_propval *val)
151 {
152 	struct acpi_sbs *sbs = to_acpi_sbs(psy);
153 	switch (psp) {
154 	case POWER_SUPPLY_PROP_ONLINE:
155 		val->intval = sbs->charger_present;
156 		break;
157 	default:
158 		return -EINVAL;
159 	}
160 	return 0;
161 }
162 
163 static int acpi_battery_technology(struct acpi_battery *battery)
164 {
165 	if (!strcasecmp("NiCd", battery->device_chemistry))
166 		return POWER_SUPPLY_TECHNOLOGY_NiCd;
167 	if (!strcasecmp("NiMH", battery->device_chemistry))
168 		return POWER_SUPPLY_TECHNOLOGY_NiMH;
169 	if (!strcasecmp("LION", battery->device_chemistry))
170 		return POWER_SUPPLY_TECHNOLOGY_LION;
171 	if (!strcasecmp("LiP", battery->device_chemistry))
172 		return POWER_SUPPLY_TECHNOLOGY_LIPO;
173 	return POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
174 }
175 
176 static int acpi_sbs_battery_get_property(struct power_supply *psy,
177 					 enum power_supply_property psp,
178 					 union power_supply_propval *val)
179 {
180 	struct acpi_battery *battery = to_acpi_battery(psy);
181 
182 	if ((!battery->present) && psp != POWER_SUPPLY_PROP_PRESENT)
183 		return -ENODEV;
184 
185 	acpi_battery_get_state(battery);
186 	switch (psp) {
187 	case POWER_SUPPLY_PROP_STATUS:
188 		if (battery->rate_now < 0)
189 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
190 		else if (battery->rate_now > 0)
191 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
192 		else
193 			val->intval = POWER_SUPPLY_STATUS_FULL;
194 		break;
195 	case POWER_SUPPLY_PROP_PRESENT:
196 		val->intval = battery->present;
197 		break;
198 	case POWER_SUPPLY_PROP_TECHNOLOGY:
199 		val->intval = acpi_battery_technology(battery);
200 		break;
201 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
202 		val->intval = battery->cycle_count;
203 		break;
204 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
205 		val->intval = battery->design_voltage *
206 			acpi_battery_vscale(battery) * 1000;
207 		break;
208 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
209 		val->intval = battery->voltage_now *
210 				acpi_battery_vscale(battery) * 1000;
211 		break;
212 	case POWER_SUPPLY_PROP_CURRENT_NOW:
213 	case POWER_SUPPLY_PROP_POWER_NOW:
214 		val->intval = abs(battery->rate_now) *
215 				acpi_battery_ipscale(battery) * 1000;
216 		val->intval *= (acpi_battery_mode(battery)) ?
217 				(battery->voltage_now *
218 				acpi_battery_vscale(battery) / 1000) : 1;
219 		break;
220 	case POWER_SUPPLY_PROP_CURRENT_AVG:
221 	case POWER_SUPPLY_PROP_POWER_AVG:
222 		val->intval = abs(battery->rate_avg) *
223 				acpi_battery_ipscale(battery) * 1000;
224 		val->intval *= (acpi_battery_mode(battery)) ?
225 				(battery->voltage_now *
226 				acpi_battery_vscale(battery) / 1000) : 1;
227 		break;
228 	case POWER_SUPPLY_PROP_CAPACITY:
229 		val->intval = battery->state_of_charge;
230 		break;
231 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
232 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
233 		val->intval = battery->design_capacity *
234 			acpi_battery_scale(battery) * 1000;
235 		break;
236 	case POWER_SUPPLY_PROP_CHARGE_FULL:
237 	case POWER_SUPPLY_PROP_ENERGY_FULL:
238 		val->intval = battery->full_charge_capacity *
239 			acpi_battery_scale(battery) * 1000;
240 		break;
241 	case POWER_SUPPLY_PROP_CHARGE_NOW:
242 	case POWER_SUPPLY_PROP_ENERGY_NOW:
243 		val->intval = battery->capacity_now *
244 				acpi_battery_scale(battery) * 1000;
245 		break;
246 	case POWER_SUPPLY_PROP_TEMP:
247 		val->intval = battery->temp_now - 2730;	// dK -> dC
248 		break;
249 	case POWER_SUPPLY_PROP_MODEL_NAME:
250 		val->strval = battery->device_name;
251 		break;
252 	case POWER_SUPPLY_PROP_MANUFACTURER:
253 		val->strval = battery->manufacturer_name;
254 		break;
255 	default:
256 		return -EINVAL;
257 	}
258 	return 0;
259 }
260 
261 static enum power_supply_property sbs_ac_props[] = {
262 	POWER_SUPPLY_PROP_ONLINE,
263 };
264 
265 static enum power_supply_property sbs_charge_battery_props[] = {
266 	POWER_SUPPLY_PROP_STATUS,
267 	POWER_SUPPLY_PROP_PRESENT,
268 	POWER_SUPPLY_PROP_TECHNOLOGY,
269 	POWER_SUPPLY_PROP_CYCLE_COUNT,
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_CAPACITY,
275 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
276 	POWER_SUPPLY_PROP_CHARGE_FULL,
277 	POWER_SUPPLY_PROP_CHARGE_NOW,
278 	POWER_SUPPLY_PROP_TEMP,
279 	POWER_SUPPLY_PROP_MODEL_NAME,
280 	POWER_SUPPLY_PROP_MANUFACTURER,
281 };
282 
283 static enum power_supply_property sbs_energy_battery_props[] = {
284 	POWER_SUPPLY_PROP_STATUS,
285 	POWER_SUPPLY_PROP_PRESENT,
286 	POWER_SUPPLY_PROP_TECHNOLOGY,
287 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
288 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
289 	POWER_SUPPLY_PROP_CURRENT_NOW,
290 	POWER_SUPPLY_PROP_CURRENT_AVG,
291 	POWER_SUPPLY_PROP_POWER_NOW,
292 	POWER_SUPPLY_PROP_POWER_AVG,
293 	POWER_SUPPLY_PROP_CAPACITY,
294 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
295 	POWER_SUPPLY_PROP_ENERGY_FULL,
296 	POWER_SUPPLY_PROP_ENERGY_NOW,
297 	POWER_SUPPLY_PROP_TEMP,
298 	POWER_SUPPLY_PROP_MODEL_NAME,
299 	POWER_SUPPLY_PROP_MANUFACTURER,
300 };
301 
302 
303 /* --------------------------------------------------------------------------
304                             Smart Battery System Management
305    -------------------------------------------------------------------------- */
306 
307 struct acpi_battery_reader {
308 	u8 command;		/* command for battery */
309 	u8 mode;		/* word or block? */
310 	size_t offset;		/* offset inside struct acpi_sbs_battery */
311 };
312 
313 static struct acpi_battery_reader info_readers[] = {
314 	{0x01, SMBUS_READ_WORD, offsetof(struct acpi_battery, alarm_capacity)},
315 	{0x03, SMBUS_READ_WORD, offsetof(struct acpi_battery, mode)},
316 	{0x10, SMBUS_READ_WORD, offsetof(struct acpi_battery, full_charge_capacity)},
317 	{0x17, SMBUS_READ_WORD, offsetof(struct acpi_battery, cycle_count)},
318 	{0x18, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_capacity)},
319 	{0x19, SMBUS_READ_WORD, offsetof(struct acpi_battery, design_voltage)},
320 	{0x1a, SMBUS_READ_WORD, offsetof(struct acpi_battery, spec)},
321 	{0x1c, SMBUS_READ_WORD, offsetof(struct acpi_battery, serial_number)},
322 	{0x20, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, manufacturer_name)},
323 	{0x21, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_name)},
324 	{0x22, SMBUS_READ_BLOCK, offsetof(struct acpi_battery, device_chemistry)},
325 };
326 
327 static struct acpi_battery_reader state_readers[] = {
328 	{0x08, SMBUS_READ_WORD, offsetof(struct acpi_battery, temp_now)},
329 	{0x09, SMBUS_READ_WORD, offsetof(struct acpi_battery, voltage_now)},
330 	{0x0a, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_now)},
331 	{0x0b, SMBUS_READ_WORD, offsetof(struct acpi_battery, rate_avg)},
332 	{0x0f, SMBUS_READ_WORD, offsetof(struct acpi_battery, capacity_now)},
333 	{0x0e, SMBUS_READ_WORD, offsetof(struct acpi_battery, state_of_charge)},
334 	{0x16, SMBUS_READ_WORD, offsetof(struct acpi_battery, state)},
335 };
336 
337 static int acpi_manager_get_info(struct acpi_sbs *sbs)
338 {
339 	int result = 0;
340 	u16 battery_system_info;
341 
342 	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,
343 				 0x04, (u8 *)&battery_system_info);
344 	if (!result)
345 		sbs->batteries_supported = battery_system_info & 0x000f;
346 	return result;
347 }
348 
349 static int acpi_battery_get_info(struct acpi_battery *battery)
350 {
351 	int i, result = 0;
352 
353 	for (i = 0; i < ARRAY_SIZE(info_readers); ++i) {
354 		result = acpi_smbus_read(battery->sbs->hc,
355 					 info_readers[i].mode,
356 					 ACPI_SBS_BATTERY,
357 					 info_readers[i].command,
358 					 (u8 *) battery +
359 						info_readers[i].offset);
360 		if (result)
361 			break;
362 	}
363 	return result;
364 }
365 
366 static int acpi_battery_get_state(struct acpi_battery *battery)
367 {
368 	int i, result = 0;
369 
370 	if (battery->update_time &&
371 	    time_before(jiffies, battery->update_time +
372 				msecs_to_jiffies(cache_time)))
373 		return 0;
374 	for (i = 0; i < ARRAY_SIZE(state_readers); ++i) {
375 		result = acpi_smbus_read(battery->sbs->hc,
376 					 state_readers[i].mode,
377 					 ACPI_SBS_BATTERY,
378 					 state_readers[i].command,
379 				         (u8 *)battery +
380 						state_readers[i].offset);
381 		if (result)
382 			goto end;
383 	}
384       end:
385 	battery->update_time = jiffies;
386 	return result;
387 }
388 
389 static int acpi_battery_get_alarm(struct acpi_battery *battery)
390 {
391 	return acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
392 				 ACPI_SBS_BATTERY, 0x01,
393 				 (u8 *)&battery->alarm_capacity);
394 }
395 
396 static int acpi_battery_set_alarm(struct acpi_battery *battery)
397 {
398 	struct acpi_sbs *sbs = battery->sbs;
399 	u16 value, sel = 1 << (battery->id + 12);
400 
401 	int ret;
402 
403 
404 	if (sbs->manager_present) {
405 		ret = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_MANAGER,
406 				0x01, (u8 *)&value);
407 		if (ret)
408 			goto end;
409 		if ((value & 0xf000) != sel) {
410 			value &= 0x0fff;
411 			value |= sel;
412 		ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD,
413 					 ACPI_SBS_MANAGER,
414 					 0x01, (u8 *)&value, 2);
415 		if (ret)
416 			goto end;
417 		}
418 	}
419 	ret = acpi_smbus_write(sbs->hc, SMBUS_WRITE_WORD, ACPI_SBS_BATTERY,
420 				0x01, (u8 *)&battery->alarm_capacity, 2);
421       end:
422 	return ret;
423 }
424 
425 static int acpi_ac_get_present(struct acpi_sbs *sbs)
426 {
427 	int result;
428 	u16 status;
429 
430 	result = acpi_smbus_read(sbs->hc, SMBUS_READ_WORD, ACPI_SBS_CHARGER,
431 				 0x13, (u8 *) & status);
432 	if (!result)
433 		sbs->charger_present = (status >> 15) & 0x1;
434 	return result;
435 }
436 
437 static ssize_t acpi_battery_alarm_show(struct device *dev,
438 					struct device_attribute *attr,
439 					char *buf)
440 {
441 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
442 	acpi_battery_get_alarm(battery);
443 	return sprintf(buf, "%d\n", battery->alarm_capacity *
444 				acpi_battery_scale(battery) * 1000);
445 }
446 
447 static ssize_t acpi_battery_alarm_store(struct device *dev,
448 					struct device_attribute *attr,
449 					const char *buf, size_t count)
450 {
451 	unsigned long x;
452 	struct acpi_battery *battery = to_acpi_battery(dev_get_drvdata(dev));
453 	if (sscanf(buf, "%ld\n", &x) == 1)
454 		battery->alarm_capacity = x /
455 			(1000 * acpi_battery_scale(battery));
456 	if (battery->present)
457 		acpi_battery_set_alarm(battery);
458 	return count;
459 }
460 
461 static struct device_attribute alarm_attr = {
462 	.attr = {.name = "alarm", .mode = 0644},
463 	.show = acpi_battery_alarm_show,
464 	.store = acpi_battery_alarm_store,
465 };
466 
467 /* --------------------------------------------------------------------------
468                                  Driver Interface
469    -------------------------------------------------------------------------- */
470 static int acpi_battery_read(struct acpi_battery *battery)
471 {
472 	int result = 0, saved_present = battery->present;
473 	u16 state;
474 
475 	if (battery->sbs->manager_present) {
476 		result = acpi_smbus_read(battery->sbs->hc, SMBUS_READ_WORD,
477 				ACPI_SBS_MANAGER, 0x01, (u8 *)&state);
478 		if (!result)
479 			battery->present = state & (1 << battery->id);
480 		state &= 0x0fff;
481 		state |= 1 << (battery->id + 12);
482 		acpi_smbus_write(battery->sbs->hc, SMBUS_WRITE_WORD,
483 				  ACPI_SBS_MANAGER, 0x01, (u8 *)&state, 2);
484 	} else if (battery->id == 0)
485 		battery->present = 1;
486 	if (result || !battery->present)
487 		return result;
488 
489 	if (saved_present != battery->present) {
490 		battery->update_time = 0;
491 		result = acpi_battery_get_info(battery);
492 		if (result)
493 			return result;
494 	}
495 	result = acpi_battery_get_state(battery);
496 	return result;
497 }
498 
499 /* Smart Battery */
500 static int acpi_battery_add(struct acpi_sbs *sbs, int id)
501 {
502 	struct acpi_battery *battery = &sbs->battery[id];
503 	int result;
504 
505 	battery->id = id;
506 	battery->sbs = sbs;
507 	result = acpi_battery_read(battery);
508 	if (result)
509 		return result;
510 
511 	sprintf(battery->name, ACPI_BATTERY_DIR_NAME, id);
512 	battery->bat.name = battery->name;
513 	battery->bat.type = POWER_SUPPLY_TYPE_BATTERY;
514 	if (!acpi_battery_mode(battery)) {
515 		battery->bat.properties = sbs_charge_battery_props;
516 		battery->bat.num_properties =
517 		    ARRAY_SIZE(sbs_charge_battery_props);
518 	} else {
519 		battery->bat.properties = sbs_energy_battery_props;
520 		battery->bat.num_properties =
521 		    ARRAY_SIZE(sbs_energy_battery_props);
522 	}
523 	battery->bat.get_property = acpi_sbs_battery_get_property;
524 	result = power_supply_register(&sbs->device->dev, &battery->bat);
525 	if (result)
526 		goto end;
527 	result = device_create_file(battery->bat.dev, &alarm_attr);
528 	if (result)
529 		goto end;
530 	battery->have_sysfs_alarm = 1;
531       end:
532 	printk(KERN_INFO PREFIX "%s [%s]: Battery Slot [%s] (battery %s)\n",
533 	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
534 	       battery->name, battery->present ? "present" : "absent");
535 	return result;
536 }
537 
538 static void acpi_battery_remove(struct acpi_sbs *sbs, int id)
539 {
540 	struct acpi_battery *battery = &sbs->battery[id];
541 
542 	if (battery->bat.dev) {
543 		if (battery->have_sysfs_alarm)
544 			device_remove_file(battery->bat.dev, &alarm_attr);
545 		power_supply_unregister(&battery->bat);
546 	}
547 }
548 
549 static int acpi_charger_add(struct acpi_sbs *sbs)
550 {
551 	int result;
552 
553 	result = acpi_ac_get_present(sbs);
554 	if (result)
555 		goto end;
556 
557 	sbs->charger.name = "sbs-charger";
558 	sbs->charger.type = POWER_SUPPLY_TYPE_MAINS;
559 	sbs->charger.properties = sbs_ac_props;
560 	sbs->charger.num_properties = ARRAY_SIZE(sbs_ac_props);
561 	sbs->charger.get_property = sbs_get_ac_property;
562 	power_supply_register(&sbs->device->dev, &sbs->charger);
563 	printk(KERN_INFO PREFIX "%s [%s]: AC Adapter [%s] (%s)\n",
564 	       ACPI_SBS_DEVICE_NAME, acpi_device_bid(sbs->device),
565 	       ACPI_AC_DIR_NAME, sbs->charger_present ? "on-line" : "off-line");
566       end:
567 	return result;
568 }
569 
570 static void acpi_charger_remove(struct acpi_sbs *sbs)
571 {
572 	if (sbs->charger.dev)
573 		power_supply_unregister(&sbs->charger);
574 }
575 
576 static void acpi_sbs_callback(void *context)
577 {
578 	int id;
579 	struct acpi_sbs *sbs = context;
580 	struct acpi_battery *bat;
581 	u8 saved_charger_state = sbs->charger_present;
582 	u8 saved_battery_state;
583 	acpi_ac_get_present(sbs);
584 	if (sbs->charger_present != saved_charger_state)
585 		kobject_uevent(&sbs->charger.dev->kobj, KOBJ_CHANGE);
586 
587 	if (sbs->manager_present) {
588 		for (id = 0; id < MAX_SBS_BAT; ++id) {
589 			if (!(sbs->batteries_supported & (1 << id)))
590 				continue;
591 			bat = &sbs->battery[id];
592 			saved_battery_state = bat->present;
593 			acpi_battery_read(bat);
594 			if (saved_battery_state == bat->present)
595 				continue;
596 			kobject_uevent(&bat->bat.dev->kobj, KOBJ_CHANGE);
597 		}
598 	}
599 }
600 
601 static int acpi_sbs_add(struct acpi_device *device)
602 {
603 	struct acpi_sbs *sbs;
604 	int result = 0;
605 	int id;
606 
607 	sbs = kzalloc(sizeof(struct acpi_sbs), GFP_KERNEL);
608 	if (!sbs) {
609 		result = -ENOMEM;
610 		goto end;
611 	}
612 
613 	mutex_init(&sbs->lock);
614 
615 	sbs->hc = acpi_driver_data(device->parent);
616 	sbs->device = device;
617 	strcpy(acpi_device_name(device), ACPI_SBS_DEVICE_NAME);
618 	strcpy(acpi_device_class(device), ACPI_SBS_CLASS);
619 	device->driver_data = sbs;
620 
621 	result = acpi_charger_add(sbs);
622 	if (result)
623 		goto end;
624 
625 	result = acpi_manager_get_info(sbs);
626 	if (!result) {
627 		sbs->manager_present = 1;
628 		for (id = 0; id < MAX_SBS_BAT; ++id)
629 			if ((sbs->batteries_supported & (1 << id)))
630 				acpi_battery_add(sbs, id);
631 	} else
632 		acpi_battery_add(sbs, 0);
633 	acpi_smbus_register_callback(sbs->hc, acpi_sbs_callback, sbs);
634       end:
635 	if (result)
636 		acpi_sbs_remove(device);
637 	return result;
638 }
639 
640 static int acpi_sbs_remove(struct acpi_device *device)
641 {
642 	struct acpi_sbs *sbs;
643 	int id;
644 
645 	if (!device)
646 		return -EINVAL;
647 	sbs = acpi_driver_data(device);
648 	if (!sbs)
649 		return -EINVAL;
650 	mutex_lock(&sbs->lock);
651 	acpi_smbus_unregister_callback(sbs->hc);
652 	for (id = 0; id < MAX_SBS_BAT; ++id)
653 		acpi_battery_remove(sbs, id);
654 	acpi_charger_remove(sbs);
655 	mutex_unlock(&sbs->lock);
656 	mutex_destroy(&sbs->lock);
657 	kfree(sbs);
658 	return 0;
659 }
660 
661 #ifdef CONFIG_PM_SLEEP
662 static int acpi_sbs_resume(struct device *dev)
663 {
664 	struct acpi_sbs *sbs;
665 	if (!dev)
666 		return -EINVAL;
667 	sbs = to_acpi_device(dev)->driver_data;
668 	acpi_sbs_callback(sbs);
669 	return 0;
670 }
671 #endif
672 
673 static SIMPLE_DEV_PM_OPS(acpi_sbs_pm, NULL, acpi_sbs_resume);
674 
675 static struct acpi_driver acpi_sbs_driver = {
676 	.name = "sbs",
677 	.class = ACPI_SBS_CLASS,
678 	.ids = sbs_device_ids,
679 	.ops = {
680 		.add = acpi_sbs_add,
681 		.remove = acpi_sbs_remove,
682 		},
683 	.drv.pm = &acpi_sbs_pm,
684 };
685 
686 static int __init acpi_sbs_init(void)
687 {
688 	int result = 0;
689 
690 	if (acpi_disabled)
691 		return -ENODEV;
692 
693 	result = acpi_bus_register_driver(&acpi_sbs_driver);
694 	if (result < 0)
695 		return -ENODEV;
696 
697 	return 0;
698 }
699 
700 static void __exit acpi_sbs_exit(void)
701 {
702 	acpi_bus_unregister_driver(&acpi_sbs_driver);
703 	return;
704 }
705 
706 module_init(acpi_sbs_init);
707 module_exit(acpi_sbs_exit);
708