1 /*
2  * Battery driver for One Laptop Per Child board.
3  *
4  *	Copyright © 2006-2010  David Woodhouse <dwmw2@infradead.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/err.h>
15 #include <linux/device.h>
16 #include <linux/platform_device.h>
17 #include <linux/power_supply.h>
18 #include <linux/jiffies.h>
19 #include <linux/sched.h>
20 #include <asm/olpc.h>
21 
22 
23 #define EC_BAT_VOLTAGE	0x10	/* uint16_t,	*9.76/32,    mV   */
24 #define EC_BAT_CURRENT	0x11	/* int16_t,	*15.625/120, mA   */
25 #define EC_BAT_ACR	0x12	/* int16_t,	*6250/15,    µAh  */
26 #define EC_BAT_TEMP	0x13	/* uint16_t,	*100/256,   °C  */
27 #define EC_AMB_TEMP	0x14	/* uint16_t,	*100/256,   °C  */
28 #define EC_BAT_STATUS	0x15	/* uint8_t,	bitmask */
29 #define EC_BAT_SOC	0x16	/* uint8_t,	percentage */
30 #define EC_BAT_SERIAL	0x17	/* uint8_t[6] */
31 #define EC_BAT_EEPROM	0x18	/* uint8_t adr as input, uint8_t output */
32 #define EC_BAT_ERRCODE	0x1f	/* uint8_t,	bitmask */
33 
34 #define BAT_STAT_PRESENT	0x01
35 #define BAT_STAT_FULL		0x02
36 #define BAT_STAT_LOW		0x04
37 #define BAT_STAT_DESTROY	0x08
38 #define BAT_STAT_AC		0x10
39 #define BAT_STAT_CHARGING	0x20
40 #define BAT_STAT_DISCHARGING	0x40
41 #define BAT_STAT_TRICKLE	0x80
42 
43 #define BAT_ERR_INFOFAIL	0x02
44 #define BAT_ERR_OVERVOLTAGE	0x04
45 #define BAT_ERR_OVERTEMP	0x05
46 #define BAT_ERR_GAUGESTOP	0x06
47 #define BAT_ERR_OUT_OF_CONTROL	0x07
48 #define BAT_ERR_ID_FAIL		0x09
49 #define BAT_ERR_ACR_FAIL	0x10
50 
51 #define BAT_ADDR_MFR_TYPE	0x5F
52 
53 /*********************************************************************
54  *		Power
55  *********************************************************************/
56 
olpc_ac_get_prop(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)57 static int olpc_ac_get_prop(struct power_supply *psy,
58 			    enum power_supply_property psp,
59 			    union power_supply_propval *val)
60 {
61 	int ret = 0;
62 	uint8_t status;
63 
64 	switch (psp) {
65 	case POWER_SUPPLY_PROP_ONLINE:
66 		ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
67 		if (ret)
68 			return ret;
69 
70 		val->intval = !!(status & BAT_STAT_AC);
71 		break;
72 	default:
73 		ret = -EINVAL;
74 		break;
75 	}
76 	return ret;
77 }
78 
79 static enum power_supply_property olpc_ac_props[] = {
80 	POWER_SUPPLY_PROP_ONLINE,
81 };
82 
83 static struct power_supply olpc_ac = {
84 	.name = "olpc-ac",
85 	.type = POWER_SUPPLY_TYPE_MAINS,
86 	.properties = olpc_ac_props,
87 	.num_properties = ARRAY_SIZE(olpc_ac_props),
88 	.get_property = olpc_ac_get_prop,
89 };
90 
91 static char bat_serial[17]; /* Ick */
92 
olpc_bat_get_status(union power_supply_propval * val,uint8_t ec_byte)93 static int olpc_bat_get_status(union power_supply_propval *val, uint8_t ec_byte)
94 {
95 	if (olpc_platform_info.ecver > 0x44) {
96 		if (ec_byte & (BAT_STAT_CHARGING | BAT_STAT_TRICKLE))
97 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
98 		else if (ec_byte & BAT_STAT_DISCHARGING)
99 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
100 		else if (ec_byte & BAT_STAT_FULL)
101 			val->intval = POWER_SUPPLY_STATUS_FULL;
102 		else /* er,... */
103 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
104 	} else {
105 		/* Older EC didn't report charge/discharge bits */
106 		if (!(ec_byte & BAT_STAT_AC)) /* No AC means discharging */
107 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
108 		else if (ec_byte & BAT_STAT_FULL)
109 			val->intval = POWER_SUPPLY_STATUS_FULL;
110 		else /* Not _necessarily_ true but EC doesn't tell all yet */
111 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
112 	}
113 
114 	return 0;
115 }
116 
olpc_bat_get_health(union power_supply_propval * val)117 static int olpc_bat_get_health(union power_supply_propval *val)
118 {
119 	uint8_t ec_byte;
120 	int ret;
121 
122 	ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
123 	if (ret)
124 		return ret;
125 
126 	switch (ec_byte) {
127 	case 0:
128 		val->intval = POWER_SUPPLY_HEALTH_GOOD;
129 		break;
130 
131 	case BAT_ERR_OVERTEMP:
132 		val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
133 		break;
134 
135 	case BAT_ERR_OVERVOLTAGE:
136 		val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
137 		break;
138 
139 	case BAT_ERR_INFOFAIL:
140 	case BAT_ERR_OUT_OF_CONTROL:
141 	case BAT_ERR_ID_FAIL:
142 	case BAT_ERR_ACR_FAIL:
143 		val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
144 		break;
145 
146 	default:
147 		/* Eep. We don't know this failure code */
148 		ret = -EIO;
149 	}
150 
151 	return ret;
152 }
153 
olpc_bat_get_mfr(union power_supply_propval * val)154 static int olpc_bat_get_mfr(union power_supply_propval *val)
155 {
156 	uint8_t ec_byte;
157 	int ret;
158 
159 	ec_byte = BAT_ADDR_MFR_TYPE;
160 	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
161 	if (ret)
162 		return ret;
163 
164 	switch (ec_byte >> 4) {
165 	case 1:
166 		val->strval = "Gold Peak";
167 		break;
168 	case 2:
169 		val->strval = "BYD";
170 		break;
171 	default:
172 		val->strval = "Unknown";
173 		break;
174 	}
175 
176 	return ret;
177 }
178 
olpc_bat_get_tech(union power_supply_propval * val)179 static int olpc_bat_get_tech(union power_supply_propval *val)
180 {
181 	uint8_t ec_byte;
182 	int ret;
183 
184 	ec_byte = BAT_ADDR_MFR_TYPE;
185 	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
186 	if (ret)
187 		return ret;
188 
189 	switch (ec_byte & 0xf) {
190 	case 1:
191 		val->intval = POWER_SUPPLY_TECHNOLOGY_NiMH;
192 		break;
193 	case 2:
194 		val->intval = POWER_SUPPLY_TECHNOLOGY_LiFe;
195 		break;
196 	default:
197 		val->intval = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
198 		break;
199 	}
200 
201 	return ret;
202 }
203 
olpc_bat_get_charge_full_design(union power_supply_propval * val)204 static int olpc_bat_get_charge_full_design(union power_supply_propval *val)
205 {
206 	uint8_t ec_byte;
207 	union power_supply_propval tech;
208 	int ret, mfr;
209 
210 	ret = olpc_bat_get_tech(&tech);
211 	if (ret)
212 		return ret;
213 
214 	ec_byte = BAT_ADDR_MFR_TYPE;
215 	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
216 	if (ret)
217 		return ret;
218 
219 	mfr = ec_byte >> 4;
220 
221 	switch (tech.intval) {
222 	case POWER_SUPPLY_TECHNOLOGY_NiMH:
223 		switch (mfr) {
224 		case 1: /* Gold Peak */
225 			val->intval = 3000000*.8;
226 			break;
227 		default:
228 			return -EIO;
229 		}
230 		break;
231 
232 	case POWER_SUPPLY_TECHNOLOGY_LiFe:
233 		switch (mfr) {
234 		case 1: /* Gold Peak */
235 			val->intval = 2800000;
236 			break;
237 		case 2: /* BYD */
238 			val->intval = 3100000;
239 			break;
240 		default:
241 			return -EIO;
242 		}
243 		break;
244 
245 	default:
246 		return -EIO;
247 	}
248 
249 	return ret;
250 }
251 
olpc_bat_get_charge_now(union power_supply_propval * val)252 static int olpc_bat_get_charge_now(union power_supply_propval *val)
253 {
254 	uint8_t soc;
255 	union power_supply_propval full;
256 	int ret;
257 
258 	ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &soc, 1);
259 	if (ret)
260 		return ret;
261 
262 	ret = olpc_bat_get_charge_full_design(&full);
263 	if (ret)
264 		return ret;
265 
266 	val->intval = soc * (full.intval / 100);
267 	return 0;
268 }
269 
270 /*********************************************************************
271  *		Battery properties
272  *********************************************************************/
olpc_bat_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)273 static int olpc_bat_get_property(struct power_supply *psy,
274 				 enum power_supply_property psp,
275 				 union power_supply_propval *val)
276 {
277 	int ret = 0;
278 	__be16 ec_word;
279 	uint8_t ec_byte;
280 	__be64 ser_buf;
281 
282 	ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &ec_byte, 1);
283 	if (ret)
284 		return ret;
285 
286 	/* Theoretically there's a race here -- the battery could be
287 	   removed immediately after we check whether it's present, and
288 	   then we query for some other property of the now-absent battery.
289 	   It doesn't matter though -- the EC will return the last-known
290 	   information, and it's as if we just ran that _little_ bit faster
291 	   and managed to read it out before the battery went away. */
292 	if (!(ec_byte & (BAT_STAT_PRESENT | BAT_STAT_TRICKLE)) &&
293 			psp != POWER_SUPPLY_PROP_PRESENT)
294 		return -ENODEV;
295 
296 	switch (psp) {
297 	case POWER_SUPPLY_PROP_STATUS:
298 		ret = olpc_bat_get_status(val, ec_byte);
299 		if (ret)
300 			return ret;
301 		break;
302 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
303 		if (ec_byte & BAT_STAT_TRICKLE)
304 			val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
305 		else if (ec_byte & BAT_STAT_CHARGING)
306 			val->intval = POWER_SUPPLY_CHARGE_TYPE_FAST;
307 		else
308 			val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
309 		break;
310 	case POWER_SUPPLY_PROP_PRESENT:
311 		val->intval = !!(ec_byte & (BAT_STAT_PRESENT |
312 					    BAT_STAT_TRICKLE));
313 		break;
314 
315 	case POWER_SUPPLY_PROP_HEALTH:
316 		if (ec_byte & BAT_STAT_DESTROY)
317 			val->intval = POWER_SUPPLY_HEALTH_DEAD;
318 		else {
319 			ret = olpc_bat_get_health(val);
320 			if (ret)
321 				return ret;
322 		}
323 		break;
324 
325 	case POWER_SUPPLY_PROP_MANUFACTURER:
326 		ret = olpc_bat_get_mfr(val);
327 		if (ret)
328 			return ret;
329 		break;
330 	case POWER_SUPPLY_PROP_TECHNOLOGY:
331 		ret = olpc_bat_get_tech(val);
332 		if (ret)
333 			return ret;
334 		break;
335 	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
336 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
337 		ret = olpc_ec_cmd(EC_BAT_VOLTAGE, NULL, 0, (void *)&ec_word, 2);
338 		if (ret)
339 			return ret;
340 
341 		val->intval = (s16)be16_to_cpu(ec_word) * 9760L / 32;
342 		break;
343 	case POWER_SUPPLY_PROP_CURRENT_AVG:
344 	case POWER_SUPPLY_PROP_CURRENT_NOW:
345 		ret = olpc_ec_cmd(EC_BAT_CURRENT, NULL, 0, (void *)&ec_word, 2);
346 		if (ret)
347 			return ret;
348 
349 		val->intval = (s16)be16_to_cpu(ec_word) * 15625L / 120;
350 		break;
351 	case POWER_SUPPLY_PROP_CAPACITY:
352 		ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &ec_byte, 1);
353 		if (ret)
354 			return ret;
355 		val->intval = ec_byte;
356 		break;
357 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
358 		if (ec_byte & BAT_STAT_FULL)
359 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
360 		else if (ec_byte & BAT_STAT_LOW)
361 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
362 		else
363 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
364 		break;
365 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
366 		ret = olpc_bat_get_charge_full_design(val);
367 		if (ret)
368 			return ret;
369 		break;
370 	case POWER_SUPPLY_PROP_CHARGE_NOW:
371 		ret = olpc_bat_get_charge_now(val);
372 		if (ret)
373 			return ret;
374 		break;
375 	case POWER_SUPPLY_PROP_TEMP:
376 		ret = olpc_ec_cmd(EC_BAT_TEMP, NULL, 0, (void *)&ec_word, 2);
377 		if (ret)
378 			return ret;
379 
380 		val->intval = (s16)be16_to_cpu(ec_word) * 100 / 256;
381 		break;
382 	case POWER_SUPPLY_PROP_TEMP_AMBIENT:
383 		ret = olpc_ec_cmd(EC_AMB_TEMP, NULL, 0, (void *)&ec_word, 2);
384 		if (ret)
385 			return ret;
386 
387 		val->intval = (int)be16_to_cpu(ec_word) * 100 / 256;
388 		break;
389 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
390 		ret = olpc_ec_cmd(EC_BAT_ACR, NULL, 0, (void *)&ec_word, 2);
391 		if (ret)
392 			return ret;
393 
394 		val->intval = (s16)be16_to_cpu(ec_word) * 6250 / 15;
395 		break;
396 	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
397 		ret = olpc_ec_cmd(EC_BAT_SERIAL, NULL, 0, (void *)&ser_buf, 8);
398 		if (ret)
399 			return ret;
400 
401 		sprintf(bat_serial, "%016llx", (long long)be64_to_cpu(ser_buf));
402 		val->strval = bat_serial;
403 		break;
404 	default:
405 		ret = -EINVAL;
406 		break;
407 	}
408 
409 	return ret;
410 }
411 
412 static enum power_supply_property olpc_xo1_bat_props[] = {
413 	POWER_SUPPLY_PROP_STATUS,
414 	POWER_SUPPLY_PROP_CHARGE_TYPE,
415 	POWER_SUPPLY_PROP_PRESENT,
416 	POWER_SUPPLY_PROP_HEALTH,
417 	POWER_SUPPLY_PROP_TECHNOLOGY,
418 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
419 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
420 	POWER_SUPPLY_PROP_CURRENT_AVG,
421 	POWER_SUPPLY_PROP_CURRENT_NOW,
422 	POWER_SUPPLY_PROP_CAPACITY,
423 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
424 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
425 	POWER_SUPPLY_PROP_CHARGE_NOW,
426 	POWER_SUPPLY_PROP_TEMP,
427 	POWER_SUPPLY_PROP_TEMP_AMBIENT,
428 	POWER_SUPPLY_PROP_MANUFACTURER,
429 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
430 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
431 };
432 
433 /* XO-1.5 does not have ambient temperature property */
434 static enum power_supply_property olpc_xo15_bat_props[] = {
435 	POWER_SUPPLY_PROP_STATUS,
436 	POWER_SUPPLY_PROP_CHARGE_TYPE,
437 	POWER_SUPPLY_PROP_PRESENT,
438 	POWER_SUPPLY_PROP_HEALTH,
439 	POWER_SUPPLY_PROP_TECHNOLOGY,
440 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
441 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
442 	POWER_SUPPLY_PROP_CURRENT_AVG,
443 	POWER_SUPPLY_PROP_CURRENT_NOW,
444 	POWER_SUPPLY_PROP_CAPACITY,
445 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
446 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
447 	POWER_SUPPLY_PROP_CHARGE_NOW,
448 	POWER_SUPPLY_PROP_TEMP,
449 	POWER_SUPPLY_PROP_MANUFACTURER,
450 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
451 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
452 };
453 
454 /* EEPROM reading goes completely around the power_supply API, sadly */
455 
456 #define EEPROM_START	0x20
457 #define EEPROM_END	0x80
458 #define EEPROM_SIZE	(EEPROM_END - EEPROM_START)
459 
olpc_bat_eeprom_read(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)460 static ssize_t olpc_bat_eeprom_read(struct file *filp, struct kobject *kobj,
461 		struct bin_attribute *attr, char *buf, loff_t off, size_t count)
462 {
463 	uint8_t ec_byte;
464 	int ret;
465 	int i;
466 
467 	if (off >= EEPROM_SIZE)
468 		return 0;
469 	if (off + count > EEPROM_SIZE)
470 		count = EEPROM_SIZE - off;
471 
472 	for (i = 0; i < count; i++) {
473 		ec_byte = EEPROM_START + off + i;
474 		ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &buf[i], 1);
475 		if (ret) {
476 			pr_err("olpc-battery: "
477 			       "EC_BAT_EEPROM cmd @ 0x%x failed - %d!\n",
478 			       ec_byte, ret);
479 			return -EIO;
480 		}
481 	}
482 
483 	return count;
484 }
485 
486 static struct bin_attribute olpc_bat_eeprom = {
487 	.attr = {
488 		.name = "eeprom",
489 		.mode = S_IRUGO,
490 	},
491 	.size = 0,
492 	.read = olpc_bat_eeprom_read,
493 };
494 
495 /* Allow userspace to see the specific error value pulled from the EC */
496 
olpc_bat_error_read(struct device * dev,struct device_attribute * attr,char * buf)497 static ssize_t olpc_bat_error_read(struct device *dev,
498 		struct device_attribute *attr, char *buf)
499 {
500 	uint8_t ec_byte;
501 	ssize_t ret;
502 
503 	ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
504 	if (ret < 0)
505 		return ret;
506 
507 	return sprintf(buf, "%d\n", ec_byte);
508 }
509 
510 static struct device_attribute olpc_bat_error = {
511 	.attr = {
512 		.name = "error",
513 		.mode = S_IRUGO,
514 	},
515 	.show = olpc_bat_error_read,
516 };
517 
518 /*********************************************************************
519  *		Initialisation
520  *********************************************************************/
521 
522 static struct power_supply olpc_bat = {
523 	.name = "olpc-battery",
524 	.get_property = olpc_bat_get_property,
525 	.use_for_apm = 1,
526 };
527 
olpc_battery_suspend(struct platform_device * pdev,pm_message_t state)528 static int olpc_battery_suspend(struct platform_device *pdev,
529 				pm_message_t state)
530 {
531 	if (device_may_wakeup(olpc_ac.dev))
532 		olpc_ec_wakeup_set(EC_SCI_SRC_ACPWR);
533 	else
534 		olpc_ec_wakeup_clear(EC_SCI_SRC_ACPWR);
535 
536 	if (device_may_wakeup(olpc_bat.dev))
537 		olpc_ec_wakeup_set(EC_SCI_SRC_BATTERY | EC_SCI_SRC_BATSOC
538 				   | EC_SCI_SRC_BATERR);
539 	else
540 		olpc_ec_wakeup_clear(EC_SCI_SRC_BATTERY | EC_SCI_SRC_BATSOC
541 				     | EC_SCI_SRC_BATERR);
542 
543 	return 0;
544 }
545 
olpc_battery_probe(struct platform_device * pdev)546 static int __devinit olpc_battery_probe(struct platform_device *pdev)
547 {
548 	int ret;
549 	uint8_t status;
550 
551 	/*
552 	 * We've seen a number of EC protocol changes; this driver requires
553 	 * the latest EC protocol, supported by 0x44 and above.
554 	 */
555 	if (olpc_platform_info.ecver < 0x44) {
556 		printk(KERN_NOTICE "OLPC EC version 0x%02x too old for "
557 			"battery driver.\n", olpc_platform_info.ecver);
558 		return -ENXIO;
559 	}
560 
561 	ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
562 	if (ret)
563 		return ret;
564 
565 	/* Ignore the status. It doesn't actually matter */
566 
567 	ret = power_supply_register(&pdev->dev, &olpc_ac);
568 	if (ret)
569 		return ret;
570 
571 	if (olpc_board_at_least(olpc_board_pre(0xd0))) { /* XO-1.5 */
572 		olpc_bat.properties = olpc_xo15_bat_props;
573 		olpc_bat.num_properties = ARRAY_SIZE(olpc_xo15_bat_props);
574 	} else { /* XO-1 */
575 		olpc_bat.properties = olpc_xo1_bat_props;
576 		olpc_bat.num_properties = ARRAY_SIZE(olpc_xo1_bat_props);
577 	}
578 
579 	ret = power_supply_register(&pdev->dev, &olpc_bat);
580 	if (ret)
581 		goto battery_failed;
582 
583 	ret = device_create_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
584 	if (ret)
585 		goto eeprom_failed;
586 
587 	ret = device_create_file(olpc_bat.dev, &olpc_bat_error);
588 	if (ret)
589 		goto error_failed;
590 
591 	if (olpc_ec_wakeup_available()) {
592 		device_set_wakeup_capable(olpc_ac.dev, true);
593 		device_set_wakeup_capable(olpc_bat.dev, true);
594 	}
595 
596 	return 0;
597 
598 error_failed:
599 	device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
600 eeprom_failed:
601 	power_supply_unregister(&olpc_bat);
602 battery_failed:
603 	power_supply_unregister(&olpc_ac);
604 	return ret;
605 }
606 
olpc_battery_remove(struct platform_device * pdev)607 static int __devexit olpc_battery_remove(struct platform_device *pdev)
608 {
609 	device_remove_file(olpc_bat.dev, &olpc_bat_error);
610 	device_remove_bin_file(olpc_bat.dev, &olpc_bat_eeprom);
611 	power_supply_unregister(&olpc_bat);
612 	power_supply_unregister(&olpc_ac);
613 	return 0;
614 }
615 
616 static const struct of_device_id olpc_battery_ids[] __devinitconst = {
617 	{ .compatible = "olpc,xo1-battery" },
618 	{}
619 };
620 MODULE_DEVICE_TABLE(of, olpc_battery_ids);
621 
622 static struct platform_driver olpc_battery_driver = {
623 	.driver = {
624 		.name = "olpc-battery",
625 		.owner = THIS_MODULE,
626 		.of_match_table = olpc_battery_ids,
627 	},
628 	.probe = olpc_battery_probe,
629 	.remove = __devexit_p(olpc_battery_remove),
630 	.suspend = olpc_battery_suspend,
631 };
632 
633 module_platform_driver(olpc_battery_driver);
634 
635 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
636 MODULE_LICENSE("GPL");
637 MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");
638