xref: /openbmc/linux/drivers/acpi/battery.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  *  acpi_battery.c - ACPI Battery Driver ($Revision: 37 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25 
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #include <linux/proc_fs.h>
31 #include <linux/seq_file.h>
32 #include <asm/uaccess.h>
33 
34 #include <acpi/acpi_bus.h>
35 #include <acpi/acpi_drivers.h>
36 
37 
38 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
39 
40 #define ACPI_BATTERY_FORMAT_BIF	"NNNNNNNNNSSSS"
41 #define ACPI_BATTERY_FORMAT_BST	"NNNN"
42 
43 #define ACPI_BATTERY_COMPONENT		0x00040000
44 #define ACPI_BATTERY_CLASS		"battery"
45 #define ACPI_BATTERY_HID		"PNP0C0A"
46 #define ACPI_BATTERY_DRIVER_NAME	"ACPI Battery Driver"
47 #define ACPI_BATTERY_DEVICE_NAME	"Battery"
48 #define ACPI_BATTERY_FILE_INFO		"info"
49 #define ACPI_BATTERY_FILE_STATUS	"state"
50 #define ACPI_BATTERY_FILE_ALARM		"alarm"
51 #define ACPI_BATTERY_NOTIFY_STATUS	0x80
52 #define ACPI_BATTERY_NOTIFY_INFO	0x81
53 #define ACPI_BATTERY_UNITS_WATTS	"mW"
54 #define ACPI_BATTERY_UNITS_AMPS		"mA"
55 
56 
57 #define _COMPONENT		ACPI_BATTERY_COMPONENT
58 ACPI_MODULE_NAME		("acpi_battery")
59 
60 MODULE_AUTHOR("Paul Diefenbaugh");
61 MODULE_DESCRIPTION(ACPI_BATTERY_DRIVER_NAME);
62 MODULE_LICENSE("GPL");
63 
64 static int acpi_battery_add (struct acpi_device *device);
65 static int acpi_battery_remove (struct acpi_device *device, int type);
66 
67 static struct acpi_driver acpi_battery_driver = {
68 	.name =		ACPI_BATTERY_DRIVER_NAME,
69 	.class =	ACPI_BATTERY_CLASS,
70 	.ids =		ACPI_BATTERY_HID,
71 	.ops =		{
72 				.add =		acpi_battery_add,
73 				.remove =	acpi_battery_remove,
74 			},
75 };
76 
77 struct acpi_battery_status {
78 	acpi_integer		state;
79 	acpi_integer		present_rate;
80 	acpi_integer		remaining_capacity;
81 	acpi_integer		present_voltage;
82 };
83 
84 struct acpi_battery_info {
85 	acpi_integer		power_unit;
86 	acpi_integer		design_capacity;
87 	acpi_integer		last_full_capacity;
88 	acpi_integer		battery_technology;
89 	acpi_integer		design_voltage;
90 	acpi_integer		design_capacity_warning;
91 	acpi_integer		design_capacity_low;
92 	acpi_integer		battery_capacity_granularity_1;
93 	acpi_integer		battery_capacity_granularity_2;
94 	acpi_string		model_number;
95 	acpi_string		serial_number;
96 	acpi_string		battery_type;
97 	acpi_string		oem_info;
98 };
99 
100 struct acpi_battery_flags {
101 	u8			present:1;	/* Bay occupied? */
102 	u8			power_unit:1;	/* 0=watts, 1=apms */
103 	u8			alarm:1;	/* _BTP present? */
104 	u8			reserved:5;
105 };
106 
107 struct acpi_battery_trips {
108 	unsigned long		warning;
109 	unsigned long		low;
110 };
111 
112 struct acpi_battery {
113 	acpi_handle		handle;
114 	struct acpi_battery_flags flags;
115 	struct acpi_battery_trips trips;
116 	unsigned long		alarm;
117 	struct acpi_battery_info *info;
118 };
119 
120 
121 /* --------------------------------------------------------------------------
122                                Battery Management
123    -------------------------------------------------------------------------- */
124 
125 static int
126 acpi_battery_get_info (
127 	struct acpi_battery	*battery,
128 	struct acpi_battery_info **bif)
129 {
130 	int			result = 0;
131 	acpi_status 		status = 0;
132 	struct acpi_buffer	buffer = {ACPI_ALLOCATE_BUFFER, NULL};
133 	struct acpi_buffer	format = {sizeof(ACPI_BATTERY_FORMAT_BIF),
134 						ACPI_BATTERY_FORMAT_BIF};
135 	struct acpi_buffer	data = {0, NULL};
136 	union acpi_object	*package = NULL;
137 
138 	ACPI_FUNCTION_TRACE("acpi_battery_get_info");
139 
140 	if (!battery || !bif)
141 		return_VALUE(-EINVAL);
142 
143 	/* Evalute _BIF */
144 
145 	status = acpi_evaluate_object(battery->handle, "_BIF", NULL, &buffer);
146 	if (ACPI_FAILURE(status)) {
147 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _BIF\n"));
148 		return_VALUE(-ENODEV);
149 	}
150 
151 	package = (union acpi_object *) buffer.pointer;
152 
153 	/* Extract Package Data */
154 
155 	status = acpi_extract_package(package, &format, &data);
156 	if (status != AE_BUFFER_OVERFLOW) {
157 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error extracting _BIF\n"));
158 		result = -ENODEV;
159 		goto end;
160 	}
161 
162 	data.pointer = kmalloc(data.length, GFP_KERNEL);
163 	if (!data.pointer) {
164 		result = -ENOMEM;
165 		goto end;
166 	}
167 	memset(data.pointer, 0, data.length);
168 
169 	status = acpi_extract_package(package, &format, &data);
170 	if (ACPI_FAILURE(status)) {
171 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error extracting _BIF\n"));
172 		kfree(data.pointer);
173 		result = -ENODEV;
174 		goto end;
175 	}
176 
177 end:
178 	acpi_os_free(buffer.pointer);
179 
180 	if (!result)
181 		(*bif) = (struct acpi_battery_info *) data.pointer;
182 
183 	return_VALUE(result);
184 }
185 
186 static int
187 acpi_battery_get_status (
188 	struct acpi_battery	*battery,
189 	struct acpi_battery_status **bst)
190 {
191 	int			result = 0;
192 	acpi_status 		status = 0;
193 	struct acpi_buffer	buffer = {ACPI_ALLOCATE_BUFFER, NULL};
194 	struct acpi_buffer	format = {sizeof(ACPI_BATTERY_FORMAT_BST),
195 						ACPI_BATTERY_FORMAT_BST};
196 	struct acpi_buffer	data = {0, NULL};
197 	union acpi_object	*package = NULL;
198 
199 	ACPI_FUNCTION_TRACE("acpi_battery_get_status");
200 
201 	if (!battery || !bst)
202 		return_VALUE(-EINVAL);
203 
204 	/* Evalute _BST */
205 
206 	status = acpi_evaluate_object(battery->handle, "_BST", NULL, &buffer);
207 	if (ACPI_FAILURE(status)) {
208 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _BST\n"));
209 		return_VALUE(-ENODEV);
210 	}
211 
212 	package = (union acpi_object *) buffer.pointer;
213 
214 	/* Extract Package Data */
215 
216 	status = acpi_extract_package(package, &format, &data);
217 	if (status != AE_BUFFER_OVERFLOW) {
218 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error extracting _BST\n"));
219 		result = -ENODEV;
220 		goto end;
221 	}
222 
223 	data.pointer = kmalloc(data.length, GFP_KERNEL);
224 	if (!data.pointer) {
225 		result = -ENOMEM;
226 		goto end;
227 	}
228 	memset(data.pointer, 0, data.length);
229 
230 	status = acpi_extract_package(package, &format, &data);
231 	if (ACPI_FAILURE(status)) {
232 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error extracting _BST\n"));
233 		kfree(data.pointer);
234 		result = -ENODEV;
235 		goto end;
236 	}
237 
238 end:
239 	acpi_os_free(buffer.pointer);
240 
241 	if (!result)
242 		(*bst) = (struct acpi_battery_status *) data.pointer;
243 
244 	return_VALUE(result);
245 }
246 
247 
248 static int
249 acpi_battery_set_alarm (
250 	struct acpi_battery	*battery,
251 	unsigned long		alarm)
252 {
253 	acpi_status		status = 0;
254 	union acpi_object	arg0 = {ACPI_TYPE_INTEGER};
255 	struct acpi_object_list	arg_list = {1, &arg0};
256 
257 	ACPI_FUNCTION_TRACE("acpi_battery_set_alarm");
258 
259 	if (!battery)
260 		return_VALUE(-EINVAL);
261 
262 	if (!battery->flags.alarm)
263 		return_VALUE(-ENODEV);
264 
265 	arg0.integer.value = alarm;
266 
267 	status = acpi_evaluate_object(battery->handle, "_BTP", &arg_list, NULL);
268 	if (ACPI_FAILURE(status))
269 		return_VALUE(-ENODEV);
270 
271 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Alarm set to %d\n", (u32) alarm));
272 
273 	battery->alarm = alarm;
274 
275 	return_VALUE(0);
276 }
277 
278 
279 static int
280 acpi_battery_check (
281 	struct acpi_battery	*battery)
282 {
283 	int			result = 0;
284 	acpi_status		status = AE_OK;
285 	acpi_handle		handle = NULL;
286 	struct acpi_device	*device = NULL;
287 	struct acpi_battery_info *bif = NULL;
288 
289 	ACPI_FUNCTION_TRACE("acpi_battery_check");
290 
291 	if (!battery)
292 		return_VALUE(-EINVAL);
293 
294 	result = acpi_bus_get_device(battery->handle, &device);
295 	if (result)
296 		return_VALUE(result);
297 
298 	result = acpi_bus_get_status(device);
299 	if (result)
300 		return_VALUE(result);
301 
302 	/* Insertion? */
303 
304 	if (!battery->flags.present && device->status.battery_present) {
305 
306 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Battery inserted\n"));
307 
308 		/* Evalute _BIF to get certain static information */
309 
310 		result = acpi_battery_get_info(battery, &bif);
311 		if (result)
312 			return_VALUE(result);
313 
314 		battery->flags.power_unit = bif->power_unit;
315 		battery->trips.warning = bif->design_capacity_warning;
316 		battery->trips.low = bif->design_capacity_low;
317 		kfree(bif);
318 
319 		/* See if alarms are supported, and if so, set default */
320 
321 		status = acpi_get_handle(battery->handle, "_BTP", &handle);
322 		if (ACPI_SUCCESS(status)) {
323 			battery->flags.alarm = 1;
324 			acpi_battery_set_alarm(battery, battery->trips.warning);
325 		}
326 	}
327 
328 	/* Removal? */
329 
330 	else if (battery->flags.present && !device->status.battery_present) {
331 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Battery removed\n"));
332 	}
333 
334 	battery->flags.present = device->status.battery_present;
335 
336 	return_VALUE(result);
337 }
338 
339 
340 /* --------------------------------------------------------------------------
341                               FS Interface (/proc)
342    -------------------------------------------------------------------------- */
343 
344 static struct proc_dir_entry	*acpi_battery_dir;
345 static int acpi_battery_read_info(struct seq_file *seq, void *offset)
346 {
347 	int			result = 0;
348 	struct acpi_battery	*battery = (struct acpi_battery *) seq->private;
349 	struct acpi_battery_info *bif = NULL;
350 	char			*units = "?";
351 
352 	ACPI_FUNCTION_TRACE("acpi_battery_read_info");
353 
354 	if (!battery)
355 		goto end;
356 
357 	if (battery->flags.present)
358 		seq_printf(seq, "present:                 yes\n");
359 	else {
360 		seq_printf(seq, "present:                 no\n");
361 		goto end;
362 	}
363 
364 	/* Battery Info (_BIF) */
365 
366 	result = acpi_battery_get_info(battery, &bif);
367 	if (result || !bif) {
368 		seq_printf(seq, "ERROR: Unable to read battery information\n");
369 		goto end;
370 	}
371 
372 	units = bif->power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
373 
374 	if (bif->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
375 		seq_printf(seq, "design capacity:         unknown\n");
376 	else
377 		seq_printf(seq, "design capacity:         %d %sh\n",
378 			(u32) bif->design_capacity, units);
379 
380 	if (bif->last_full_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
381 		seq_printf(seq, "last full capacity:      unknown\n");
382 	else
383 		seq_printf(seq, "last full capacity:      %d %sh\n",
384 			(u32) bif->last_full_capacity, units);
385 
386 	switch ((u32) bif->battery_technology) {
387 	case 0:
388 		seq_printf(seq, "battery technology:      non-rechargeable\n");
389 		break;
390 	case 1:
391 		seq_printf(seq, "battery technology:      rechargeable\n");
392 		break;
393 	default:
394 		seq_printf(seq, "battery technology:      unknown\n");
395 		break;
396 	}
397 
398 	if (bif->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
399 		seq_printf(seq, "design voltage:          unknown\n");
400 	else
401 		seq_printf(seq, "design voltage:          %d mV\n",
402 			(u32) bif->design_voltage);
403 
404 	seq_printf(seq, "design capacity warning: %d %sh\n",
405 		(u32) bif->design_capacity_warning, units);
406 	seq_printf(seq, "design capacity low:     %d %sh\n",
407 		(u32) bif->design_capacity_low, units);
408 	seq_printf(seq, "capacity granularity 1:  %d %sh\n",
409 		(u32) bif->battery_capacity_granularity_1, units);
410 	seq_printf(seq, "capacity granularity 2:  %d %sh\n",
411 		(u32) bif->battery_capacity_granularity_2, units);
412 	seq_printf(seq, "model number:            %s\n",
413 		bif->model_number);
414 	seq_printf(seq, "serial number:           %s\n",
415 		bif->serial_number);
416 	seq_printf(seq, "battery type:            %s\n",
417 		bif->battery_type);
418 	seq_printf(seq, "OEM info:                %s\n",
419 		bif->oem_info);
420 
421 end:
422 	kfree(bif);
423 
424 	return_VALUE(0);
425 }
426 
427 static int acpi_battery_info_open_fs(struct inode *inode, struct file *file)
428 {
429 	return single_open(file, acpi_battery_read_info, PDE(inode)->data);
430 }
431 
432 
433 static int
434 acpi_battery_read_state (struct seq_file *seq, void *offset)
435 {
436 	int			result = 0;
437 	struct acpi_battery	*battery = (struct acpi_battery *) seq->private;
438 	struct acpi_battery_status *bst = NULL;
439 	char			*units = "?";
440 
441 	ACPI_FUNCTION_TRACE("acpi_battery_read_state");
442 
443 	if (!battery)
444 		goto end;
445 
446 	if (battery->flags.present)
447 		seq_printf(seq, "present:                 yes\n");
448 	else {
449 		seq_printf(seq, "present:                 no\n");
450 		goto end;
451 	}
452 
453 	/* Battery Units */
454 
455 	units = battery->flags.power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
456 
457 	/* Battery Status (_BST) */
458 
459 	result = acpi_battery_get_status(battery, &bst);
460 	if (result || !bst) {
461 		seq_printf(seq, "ERROR: Unable to read battery status\n");
462 		goto end;
463 	}
464 
465 	if (!(bst->state & 0x04))
466 		seq_printf(seq, "capacity state:          ok\n");
467 	else
468 		seq_printf(seq, "capacity state:          critical\n");
469 
470 	if ((bst->state & 0x01) && (bst->state & 0x02)){
471 		seq_printf(seq, "charging state:          charging/discharging\n");
472 		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
473 					"Battery Charging and Discharging?\n"));
474 	}
475 	else if (bst->state & 0x01)
476 		seq_printf(seq, "charging state:          discharging\n");
477 	else if (bst->state & 0x02)
478 		seq_printf(seq, "charging state:          charging\n");
479 	else {
480 		seq_printf(seq, "charging state:          charged\n");
481 	}
482 
483 	if (bst->present_rate == ACPI_BATTERY_VALUE_UNKNOWN)
484 		seq_printf(seq, "present rate:            unknown\n");
485 	else
486 		seq_printf(seq, "present rate:            %d %s\n",
487 			(u32) bst->present_rate, units);
488 
489 	if (bst->remaining_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
490 		seq_printf(seq, "remaining capacity:      unknown\n");
491 	else
492 		seq_printf(seq, "remaining capacity:      %d %sh\n",
493 			(u32) bst->remaining_capacity, units);
494 
495 	if (bst->present_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
496 		seq_printf(seq, "present voltage:         unknown\n");
497 	else
498 		seq_printf(seq, "present voltage:         %d mV\n",
499 			(u32) bst->present_voltage);
500 
501 end:
502 	kfree(bst);
503 
504 	return_VALUE(0);
505 }
506 
507 static int acpi_battery_state_open_fs(struct inode *inode, struct file *file)
508 {
509 	return single_open(file, acpi_battery_read_state, PDE(inode)->data);
510 }
511 
512 
513 static int
514 acpi_battery_read_alarm (struct seq_file *seq, void *offset)
515 {
516 	struct acpi_battery	*battery = (struct acpi_battery *) seq->private;
517 	char			*units = "?";
518 
519 	ACPI_FUNCTION_TRACE("acpi_battery_read_alarm");
520 
521 	if (!battery)
522 		goto end;
523 
524 	if (!battery->flags.present) {
525 		seq_printf(seq, "present:                 no\n");
526 		goto end;
527 	}
528 
529 	/* Battery Units */
530 
531 	units = battery->flags.power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;
532 
533 	/* Battery Alarm */
534 
535 	seq_printf(seq, "alarm:                   ");
536 	if (!battery->alarm)
537 		seq_printf(seq, "unsupported\n");
538 	else
539 		seq_printf(seq, "%d %sh\n", (u32) battery->alarm, units);
540 
541 end:
542 	return_VALUE(0);
543 }
544 
545 
546 static ssize_t
547 acpi_battery_write_alarm (
548 	struct file	*file,
549 	const char	__user *buffer,
550 	size_t		count,
551 	loff_t		*ppos)
552 {
553 	int			result = 0;
554 	char			alarm_string[12] = {'\0'};
555 	struct seq_file		*m = (struct seq_file *)file->private_data;
556 	struct acpi_battery	*battery = (struct acpi_battery *)m->private;
557 
558 	ACPI_FUNCTION_TRACE("acpi_battery_write_alarm");
559 
560 	if (!battery || (count > sizeof(alarm_string) - 1))
561 		return_VALUE(-EINVAL);
562 
563 	if (!battery->flags.present)
564 		return_VALUE(-ENODEV);
565 
566 	if (copy_from_user(alarm_string, buffer, count))
567 		return_VALUE(-EFAULT);
568 
569 	alarm_string[count] = '\0';
570 
571 	result = acpi_battery_set_alarm(battery,
572 		simple_strtoul(alarm_string, NULL, 0));
573 	if (result)
574 		return_VALUE(result);
575 
576 	return_VALUE(count);
577 }
578 
579 static int acpi_battery_alarm_open_fs(struct inode *inode, struct file *file)
580 {
581 	return single_open(file, acpi_battery_read_alarm, PDE(inode)->data);
582 }
583 
584 static struct file_operations acpi_battery_info_ops = {
585 	.open		= acpi_battery_info_open_fs,
586 	.read		= seq_read,
587 	.llseek		= seq_lseek,
588 	.release	= single_release,
589 	.owner = THIS_MODULE,
590 };
591 
592 static struct file_operations acpi_battery_state_ops = {
593 	.open		= acpi_battery_state_open_fs,
594 	.read		= seq_read,
595 	.llseek		= seq_lseek,
596 	.release	= single_release,
597 	.owner = THIS_MODULE,
598 };
599 
600 static struct file_operations acpi_battery_alarm_ops = {
601 	.open		= acpi_battery_alarm_open_fs,
602 	.read		= seq_read,
603 	.write		= acpi_battery_write_alarm,
604 	.llseek		= seq_lseek,
605 	.release	= single_release,
606 	.owner = THIS_MODULE,
607 };
608 
609 static int
610 acpi_battery_add_fs (
611 	struct acpi_device	*device)
612 {
613 	struct proc_dir_entry	*entry = NULL;
614 
615 	ACPI_FUNCTION_TRACE("acpi_battery_add_fs");
616 
617 	if (!acpi_device_dir(device)) {
618 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
619 			acpi_battery_dir);
620 		if (!acpi_device_dir(device))
621 			return_VALUE(-ENODEV);
622 		acpi_device_dir(device)->owner = THIS_MODULE;
623 	}
624 
625 	/* 'info' [R] */
626 	entry = create_proc_entry(ACPI_BATTERY_FILE_INFO,
627 		S_IRUGO, acpi_device_dir(device));
628 	if (!entry)
629 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
630 			"Unable to create '%s' fs entry\n",
631 			ACPI_BATTERY_FILE_INFO));
632 	else {
633 		entry->proc_fops = &acpi_battery_info_ops;
634 		entry->data = acpi_driver_data(device);
635 		entry->owner = THIS_MODULE;
636 	}
637 
638 	/* 'status' [R] */
639 	entry = create_proc_entry(ACPI_BATTERY_FILE_STATUS,
640 		S_IRUGO, acpi_device_dir(device));
641 	if (!entry)
642 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
643 			"Unable to create '%s' fs entry\n",
644 			ACPI_BATTERY_FILE_STATUS));
645 	else {
646 		entry->proc_fops = &acpi_battery_state_ops;
647 		entry->data = acpi_driver_data(device);
648 		entry->owner = THIS_MODULE;
649 	}
650 
651 	/* 'alarm' [R/W] */
652 	entry = create_proc_entry(ACPI_BATTERY_FILE_ALARM,
653 		S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
654 	if (!entry)
655 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
656 			"Unable to create '%s' fs entry\n",
657 			ACPI_BATTERY_FILE_ALARM));
658 	else {
659 		entry->proc_fops = &acpi_battery_alarm_ops;
660 		entry->data = acpi_driver_data(device);
661 		entry->owner = THIS_MODULE;
662 	}
663 
664 	return_VALUE(0);
665 }
666 
667 
668 static int
669 acpi_battery_remove_fs (
670 	struct acpi_device	*device)
671 {
672 	ACPI_FUNCTION_TRACE("acpi_battery_remove_fs");
673 
674 	if (acpi_device_dir(device)) {
675 		remove_proc_entry(ACPI_BATTERY_FILE_ALARM,
676 				  acpi_device_dir(device));
677 		remove_proc_entry(ACPI_BATTERY_FILE_STATUS,
678 				  acpi_device_dir(device));
679 		remove_proc_entry(ACPI_BATTERY_FILE_INFO,
680 				  acpi_device_dir(device));
681 
682 		remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
683 		acpi_device_dir(device) = NULL;
684 	}
685 
686 	return_VALUE(0);
687 }
688 
689 
690 /* --------------------------------------------------------------------------
691                                  Driver Interface
692    -------------------------------------------------------------------------- */
693 
694 static void
695 acpi_battery_notify (
696 	acpi_handle		handle,
697 	u32			event,
698 	void			*data)
699 {
700 	struct acpi_battery	*battery = (struct acpi_battery *) data;
701 	struct acpi_device	*device = NULL;
702 
703 	ACPI_FUNCTION_TRACE("acpi_battery_notify");
704 
705 	if (!battery)
706 		return_VOID;
707 
708 	if (acpi_bus_get_device(handle, &device))
709 		return_VOID;
710 
711 	switch (event) {
712 	case ACPI_BATTERY_NOTIFY_STATUS:
713 	case ACPI_BATTERY_NOTIFY_INFO:
714 		acpi_battery_check(battery);
715 		acpi_bus_generate_event(device, event, battery->flags.present);
716 		break;
717 	default:
718 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
719 			"Unsupported event [0x%x]\n", event));
720 		break;
721 	}
722 
723 	return_VOID;
724 }
725 
726 
727 static int
728 acpi_battery_add (
729 	struct acpi_device	*device)
730 {
731 	int			result = 0;
732 	acpi_status		status = 0;
733 	struct acpi_battery	*battery = NULL;
734 
735 	ACPI_FUNCTION_TRACE("acpi_battery_add");
736 
737 	if (!device)
738 		return_VALUE(-EINVAL);
739 
740 	battery = kmalloc(sizeof(struct acpi_battery), GFP_KERNEL);
741 	if (!battery)
742 		return_VALUE(-ENOMEM);
743 	memset(battery, 0, sizeof(struct acpi_battery));
744 
745 	battery->handle = device->handle;
746 	strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
747 	strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
748 	acpi_driver_data(device) = battery;
749 
750 	result = acpi_battery_check(battery);
751 	if (result)
752 		goto end;
753 
754 	result = acpi_battery_add_fs(device);
755 	if (result)
756 		goto end;
757 
758 	status = acpi_install_notify_handler(battery->handle,
759 		ACPI_DEVICE_NOTIFY, acpi_battery_notify, battery);
760 	if (ACPI_FAILURE(status)) {
761 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
762 			"Error installing notify handler\n"));
763 		result = -ENODEV;
764 		goto end;
765 	}
766 
767 	printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
768 		ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
769 		device->status.battery_present?"present":"absent");
770 
771 end:
772 	if (result) {
773 		acpi_battery_remove_fs(device);
774 		kfree(battery);
775 	}
776 
777 	return_VALUE(result);
778 }
779 
780 
781 static int
782 acpi_battery_remove (
783 	struct acpi_device	*device,
784 	int			type)
785 {
786 	acpi_status		status = 0;
787 	struct acpi_battery	*battery = NULL;
788 
789 	ACPI_FUNCTION_TRACE("acpi_battery_remove");
790 
791 	if (!device || !acpi_driver_data(device))
792 		return_VALUE(-EINVAL);
793 
794 	battery = (struct acpi_battery *) acpi_driver_data(device);
795 
796 	status = acpi_remove_notify_handler(battery->handle,
797 		ACPI_DEVICE_NOTIFY, acpi_battery_notify);
798 	if (ACPI_FAILURE(status))
799 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
800 			"Error removing notify handler\n"));
801 
802 	acpi_battery_remove_fs(device);
803 
804 	kfree(battery);
805 
806 	return_VALUE(0);
807 }
808 
809 
810 static int __init
811 acpi_battery_init (void)
812 {
813 	int			result = 0;
814 
815 	ACPI_FUNCTION_TRACE("acpi_battery_init");
816 
817 	acpi_battery_dir = proc_mkdir(ACPI_BATTERY_CLASS, acpi_root_dir);
818 	if (!acpi_battery_dir)
819 		return_VALUE(-ENODEV);
820 	acpi_battery_dir->owner = THIS_MODULE;
821 
822 	result = acpi_bus_register_driver(&acpi_battery_driver);
823 	if (result < 0) {
824 		remove_proc_entry(ACPI_BATTERY_CLASS, acpi_root_dir);
825 		return_VALUE(-ENODEV);
826 	}
827 
828 	return_VALUE(0);
829 }
830 
831 
832 static void __exit
833 acpi_battery_exit (void)
834 {
835 	ACPI_FUNCTION_TRACE("acpi_battery_exit");
836 
837 	acpi_bus_unregister_driver(&acpi_battery_driver);
838 
839 	remove_proc_entry(ACPI_BATTERY_CLASS, acpi_root_dir);
840 
841 	return_VOID;
842 }
843 
844 
845 module_init(acpi_battery_init);
846 module_exit(acpi_battery_exit);
847