1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Battery driver for One Laptop Per Child board.
4  *
5  *	Copyright © 2006-2010  David Woodhouse <dwmw2@infradead.org>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/mod_devicetable.h>
11 #include <linux/types.h>
12 #include <linux/err.h>
13 #include <linux/device.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/power_supply.h>
17 #include <linux/jiffies.h>
18 #include <linux/sched.h>
19 #include <linux/olpc-ec.h>
20 
21 
22 #define EC_BAT_VOLTAGE	0x10	/* uint16_t,	*9.76/32,    mV   */
23 #define EC_BAT_CURRENT	0x11	/* int16_t,	*15.625/120, mA   */
24 #define EC_BAT_ACR	0x12	/* int16_t,	*6250/15,    µAh  */
25 #define EC_BAT_TEMP	0x13	/* uint16_t,	*100/256,   °C  */
26 #define EC_AMB_TEMP	0x14	/* uint16_t,	*100/256,   °C  */
27 #define EC_BAT_STATUS	0x15	/* uint8_t,	bitmask */
28 #define EC_BAT_SOC	0x16	/* uint8_t,	percentage */
29 #define EC_BAT_SERIAL	0x17	/* uint8_t[6] */
30 #define EC_BAT_EEPROM	0x18	/* uint8_t adr as input, uint8_t output */
31 #define EC_BAT_ERRCODE	0x1f	/* uint8_t,	bitmask */
32 
33 #define BAT_STAT_PRESENT	0x01
34 #define BAT_STAT_FULL		0x02
35 #define BAT_STAT_LOW		0x04
36 #define BAT_STAT_DESTROY	0x08
37 #define BAT_STAT_AC		0x10
38 #define BAT_STAT_CHARGING	0x20
39 #define BAT_STAT_DISCHARGING	0x40
40 #define BAT_STAT_TRICKLE	0x80
41 
42 #define BAT_ERR_INFOFAIL	0x02
43 #define BAT_ERR_OVERVOLTAGE	0x04
44 #define BAT_ERR_OVERTEMP	0x05
45 #define BAT_ERR_GAUGESTOP	0x06
46 #define BAT_ERR_OUT_OF_CONTROL	0x07
47 #define BAT_ERR_ID_FAIL		0x09
48 #define BAT_ERR_ACR_FAIL	0x10
49 
50 #define BAT_ADDR_MFR_TYPE	0x5F
51 
52 struct olpc_battery_data {
53 	struct power_supply *olpc_ac;
54 	struct power_supply *olpc_bat;
55 	char bat_serial[17];
56 	bool new_proto;
57 	bool little_endian;
58 };
59 
60 /*********************************************************************
61  *		Power
62  *********************************************************************/
63 
64 static int olpc_ac_get_prop(struct power_supply *psy,
65 			    enum power_supply_property psp,
66 			    union power_supply_propval *val)
67 {
68 	int ret = 0;
69 	uint8_t status;
70 
71 	switch (psp) {
72 	case POWER_SUPPLY_PROP_ONLINE:
73 		ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
74 		if (ret)
75 			return ret;
76 
77 		val->intval = !!(status & BAT_STAT_AC);
78 		break;
79 	default:
80 		ret = -EINVAL;
81 		break;
82 	}
83 	return ret;
84 }
85 
86 static enum power_supply_property olpc_ac_props[] = {
87 	POWER_SUPPLY_PROP_ONLINE,
88 };
89 
90 static const struct power_supply_desc olpc_ac_desc = {
91 	.name = "olpc_ac",
92 	.type = POWER_SUPPLY_TYPE_MAINS,
93 	.properties = olpc_ac_props,
94 	.num_properties = ARRAY_SIZE(olpc_ac_props),
95 	.get_property = olpc_ac_get_prop,
96 };
97 
98 static int olpc_bat_get_status(struct olpc_battery_data *data,
99 		union power_supply_propval *val, uint8_t ec_byte)
100 {
101 	if (data->new_proto) {
102 		if (ec_byte & (BAT_STAT_CHARGING | BAT_STAT_TRICKLE))
103 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
104 		else if (ec_byte & BAT_STAT_DISCHARGING)
105 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
106 		else if (ec_byte & BAT_STAT_FULL)
107 			val->intval = POWER_SUPPLY_STATUS_FULL;
108 		else /* er,... */
109 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
110 	} else {
111 		/* Older EC didn't report charge/discharge bits */
112 		if (!(ec_byte & BAT_STAT_AC)) /* No AC means discharging */
113 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
114 		else if (ec_byte & BAT_STAT_FULL)
115 			val->intval = POWER_SUPPLY_STATUS_FULL;
116 		else /* Not _necessarily_ true but EC doesn't tell all yet */
117 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
118 	}
119 
120 	return 0;
121 }
122 
123 static int olpc_bat_get_health(union power_supply_propval *val)
124 {
125 	uint8_t ec_byte;
126 	int ret;
127 
128 	ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
129 	if (ret)
130 		return ret;
131 
132 	switch (ec_byte) {
133 	case 0:
134 		val->intval = POWER_SUPPLY_HEALTH_GOOD;
135 		break;
136 
137 	case BAT_ERR_OVERTEMP:
138 		val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
139 		break;
140 
141 	case BAT_ERR_OVERVOLTAGE:
142 		val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
143 		break;
144 
145 	case BAT_ERR_INFOFAIL:
146 	case BAT_ERR_OUT_OF_CONTROL:
147 	case BAT_ERR_ID_FAIL:
148 	case BAT_ERR_ACR_FAIL:
149 		val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
150 		break;
151 
152 	default:
153 		/* Eep. We don't know this failure code */
154 		ret = -EIO;
155 	}
156 
157 	return ret;
158 }
159 
160 static int olpc_bat_get_mfr(union power_supply_propval *val)
161 {
162 	uint8_t ec_byte;
163 	int ret;
164 
165 	ec_byte = BAT_ADDR_MFR_TYPE;
166 	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
167 	if (ret)
168 		return ret;
169 
170 	switch (ec_byte >> 4) {
171 	case 1:
172 		val->strval = "Gold Peak";
173 		break;
174 	case 2:
175 		val->strval = "BYD";
176 		break;
177 	default:
178 		val->strval = "Unknown";
179 		break;
180 	}
181 
182 	return ret;
183 }
184 
185 static int olpc_bat_get_tech(union power_supply_propval *val)
186 {
187 	uint8_t ec_byte;
188 	int ret;
189 
190 	ec_byte = BAT_ADDR_MFR_TYPE;
191 	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
192 	if (ret)
193 		return ret;
194 
195 	switch (ec_byte & 0xf) {
196 	case 1:
197 		val->intval = POWER_SUPPLY_TECHNOLOGY_NiMH;
198 		break;
199 	case 2:
200 		val->intval = POWER_SUPPLY_TECHNOLOGY_LiFe;
201 		break;
202 	default:
203 		val->intval = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
204 		break;
205 	}
206 
207 	return ret;
208 }
209 
210 static int olpc_bat_get_charge_full_design(union power_supply_propval *val)
211 {
212 	uint8_t ec_byte;
213 	union power_supply_propval tech;
214 	int ret, mfr;
215 
216 	ret = olpc_bat_get_tech(&tech);
217 	if (ret)
218 		return ret;
219 
220 	ec_byte = BAT_ADDR_MFR_TYPE;
221 	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
222 	if (ret)
223 		return ret;
224 
225 	mfr = ec_byte >> 4;
226 
227 	switch (tech.intval) {
228 	case POWER_SUPPLY_TECHNOLOGY_NiMH:
229 		switch (mfr) {
230 		case 1: /* Gold Peak */
231 			val->intval = 3000000*.8;
232 			break;
233 		default:
234 			return -EIO;
235 		}
236 		break;
237 
238 	case POWER_SUPPLY_TECHNOLOGY_LiFe:
239 		switch (mfr) {
240 		case 1: /* Gold Peak, fall through */
241 		case 2: /* BYD */
242 			val->intval = 2800000;
243 			break;
244 		default:
245 			return -EIO;
246 		}
247 		break;
248 
249 	default:
250 		return -EIO;
251 	}
252 
253 	return ret;
254 }
255 
256 static int olpc_bat_get_charge_now(union power_supply_propval *val)
257 {
258 	uint8_t soc;
259 	union power_supply_propval full;
260 	int ret;
261 
262 	ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &soc, 1);
263 	if (ret)
264 		return ret;
265 
266 	ret = olpc_bat_get_charge_full_design(&full);
267 	if (ret)
268 		return ret;
269 
270 	val->intval = soc * (full.intval / 100);
271 	return 0;
272 }
273 
274 static int olpc_bat_get_voltage_max_design(union power_supply_propval *val)
275 {
276 	uint8_t ec_byte;
277 	union power_supply_propval tech;
278 	int mfr;
279 	int ret;
280 
281 	ret = olpc_bat_get_tech(&tech);
282 	if (ret)
283 		return ret;
284 
285 	ec_byte = BAT_ADDR_MFR_TYPE;
286 	ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
287 	if (ret)
288 		return ret;
289 
290 	mfr = ec_byte >> 4;
291 
292 	switch (tech.intval) {
293 	case POWER_SUPPLY_TECHNOLOGY_NiMH:
294 		switch (mfr) {
295 		case 1: /* Gold Peak */
296 			val->intval = 6000000;
297 			break;
298 		default:
299 			return -EIO;
300 		}
301 		break;
302 
303 	case POWER_SUPPLY_TECHNOLOGY_LiFe:
304 		switch (mfr) {
305 		case 1: /* Gold Peak */
306 			val->intval = 6400000;
307 			break;
308 		case 2: /* BYD */
309 			val->intval = 6500000;
310 			break;
311 		default:
312 			return -EIO;
313 		}
314 		break;
315 
316 	default:
317 		return -EIO;
318 	}
319 
320 	return ret;
321 }
322 
323 static u16 ecword_to_cpu(struct olpc_battery_data *data, u16 ec_word)
324 {
325 	if (data->little_endian)
326 		return le16_to_cpu((__force __le16)ec_word);
327 	else
328 		return be16_to_cpu((__force __be16)ec_word);
329 }
330 
331 /*********************************************************************
332  *		Battery properties
333  *********************************************************************/
334 static int olpc_bat_get_property(struct power_supply *psy,
335 				 enum power_supply_property psp,
336 				 union power_supply_propval *val)
337 {
338 	struct olpc_battery_data *data = power_supply_get_drvdata(psy);
339 	int ret = 0;
340 	u16 ec_word;
341 	uint8_t ec_byte;
342 	__be64 ser_buf;
343 
344 	ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &ec_byte, 1);
345 	if (ret)
346 		return ret;
347 
348 	/* Theoretically there's a race here -- the battery could be
349 	   removed immediately after we check whether it's present, and
350 	   then we query for some other property of the now-absent battery.
351 	   It doesn't matter though -- the EC will return the last-known
352 	   information, and it's as if we just ran that _little_ bit faster
353 	   and managed to read it out before the battery went away. */
354 	if (!(ec_byte & (BAT_STAT_PRESENT | BAT_STAT_TRICKLE)) &&
355 			psp != POWER_SUPPLY_PROP_PRESENT)
356 		return -ENODEV;
357 
358 	switch (psp) {
359 	case POWER_SUPPLY_PROP_STATUS:
360 		ret = olpc_bat_get_status(data, val, ec_byte);
361 		if (ret)
362 			return ret;
363 		break;
364 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
365 		if (ec_byte & BAT_STAT_TRICKLE)
366 			val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
367 		else if (ec_byte & BAT_STAT_CHARGING)
368 			val->intval = POWER_SUPPLY_CHARGE_TYPE_FAST;
369 		else
370 			val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
371 		break;
372 	case POWER_SUPPLY_PROP_PRESENT:
373 		val->intval = !!(ec_byte & (BAT_STAT_PRESENT |
374 					    BAT_STAT_TRICKLE));
375 		break;
376 
377 	case POWER_SUPPLY_PROP_HEALTH:
378 		if (ec_byte & BAT_STAT_DESTROY)
379 			val->intval = POWER_SUPPLY_HEALTH_DEAD;
380 		else {
381 			ret = olpc_bat_get_health(val);
382 			if (ret)
383 				return ret;
384 		}
385 		break;
386 
387 	case POWER_SUPPLY_PROP_MANUFACTURER:
388 		ret = olpc_bat_get_mfr(val);
389 		if (ret)
390 			return ret;
391 		break;
392 	case POWER_SUPPLY_PROP_TECHNOLOGY:
393 		ret = olpc_bat_get_tech(val);
394 		if (ret)
395 			return ret;
396 		break;
397 	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
398 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
399 		ret = olpc_ec_cmd(EC_BAT_VOLTAGE, NULL, 0, (void *)&ec_word, 2);
400 		if (ret)
401 			return ret;
402 
403 		val->intval = ecword_to_cpu(data, ec_word) * 9760L / 32;
404 		break;
405 	case POWER_SUPPLY_PROP_CURRENT_AVG:
406 	case POWER_SUPPLY_PROP_CURRENT_NOW:
407 		ret = olpc_ec_cmd(EC_BAT_CURRENT, NULL, 0, (void *)&ec_word, 2);
408 		if (ret)
409 			return ret;
410 
411 		val->intval = ecword_to_cpu(data, ec_word) * 15625L / 120;
412 		break;
413 	case POWER_SUPPLY_PROP_CAPACITY:
414 		ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &ec_byte, 1);
415 		if (ret)
416 			return ret;
417 		val->intval = ec_byte;
418 		break;
419 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
420 		if (ec_byte & BAT_STAT_FULL)
421 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
422 		else if (ec_byte & BAT_STAT_LOW)
423 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
424 		else
425 			val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
426 		break;
427 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
428 		ret = olpc_bat_get_charge_full_design(val);
429 		if (ret)
430 			return ret;
431 		break;
432 	case POWER_SUPPLY_PROP_CHARGE_NOW:
433 		ret = olpc_bat_get_charge_now(val);
434 		if (ret)
435 			return ret;
436 		break;
437 	case POWER_SUPPLY_PROP_TEMP:
438 		ret = olpc_ec_cmd(EC_BAT_TEMP, NULL, 0, (void *)&ec_word, 2);
439 		if (ret)
440 			return ret;
441 
442 		val->intval = ecword_to_cpu(data, ec_word) * 10 / 256;
443 		break;
444 	case POWER_SUPPLY_PROP_TEMP_AMBIENT:
445 		ret = olpc_ec_cmd(EC_AMB_TEMP, NULL, 0, (void *)&ec_word, 2);
446 		if (ret)
447 			return ret;
448 
449 		val->intval = (int)ecword_to_cpu(data, ec_word) * 10 / 256;
450 		break;
451 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
452 		ret = olpc_ec_cmd(EC_BAT_ACR, NULL, 0, (void *)&ec_word, 2);
453 		if (ret)
454 			return ret;
455 
456 		val->intval = ecword_to_cpu(data, ec_word) * 6250 / 15;
457 		break;
458 	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
459 		ret = olpc_ec_cmd(EC_BAT_SERIAL, NULL, 0, (void *)&ser_buf, 8);
460 		if (ret)
461 			return ret;
462 
463 		sprintf(data->bat_serial, "%016llx", (long long)be64_to_cpu(ser_buf));
464 		val->strval = data->bat_serial;
465 		break;
466 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
467 		ret = olpc_bat_get_voltage_max_design(val);
468 		if (ret)
469 			return ret;
470 		break;
471 	default:
472 		ret = -EINVAL;
473 		break;
474 	}
475 
476 	return ret;
477 }
478 
479 static enum power_supply_property olpc_xo1_bat_props[] = {
480 	POWER_SUPPLY_PROP_STATUS,
481 	POWER_SUPPLY_PROP_CHARGE_TYPE,
482 	POWER_SUPPLY_PROP_PRESENT,
483 	POWER_SUPPLY_PROP_HEALTH,
484 	POWER_SUPPLY_PROP_TECHNOLOGY,
485 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
486 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
487 	POWER_SUPPLY_PROP_CURRENT_AVG,
488 	POWER_SUPPLY_PROP_CURRENT_NOW,
489 	POWER_SUPPLY_PROP_CAPACITY,
490 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
491 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
492 	POWER_SUPPLY_PROP_CHARGE_NOW,
493 	POWER_SUPPLY_PROP_TEMP,
494 	POWER_SUPPLY_PROP_TEMP_AMBIENT,
495 	POWER_SUPPLY_PROP_MANUFACTURER,
496 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
497 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
498 	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
499 };
500 
501 /* XO-1.5 does not have ambient temperature property */
502 static enum power_supply_property olpc_xo15_bat_props[] = {
503 	POWER_SUPPLY_PROP_STATUS,
504 	POWER_SUPPLY_PROP_CHARGE_TYPE,
505 	POWER_SUPPLY_PROP_PRESENT,
506 	POWER_SUPPLY_PROP_HEALTH,
507 	POWER_SUPPLY_PROP_TECHNOLOGY,
508 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
509 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
510 	POWER_SUPPLY_PROP_CURRENT_AVG,
511 	POWER_SUPPLY_PROP_CURRENT_NOW,
512 	POWER_SUPPLY_PROP_CAPACITY,
513 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
514 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
515 	POWER_SUPPLY_PROP_CHARGE_NOW,
516 	POWER_SUPPLY_PROP_TEMP,
517 	POWER_SUPPLY_PROP_MANUFACTURER,
518 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
519 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
520 	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
521 };
522 
523 /* EEPROM reading goes completely around the power_supply API, sadly */
524 
525 #define EEPROM_START	0x20
526 #define EEPROM_END	0x80
527 #define EEPROM_SIZE	(EEPROM_END - EEPROM_START)
528 
529 static ssize_t olpc_bat_eeprom_read(struct file *filp, struct kobject *kobj,
530 		struct bin_attribute *attr, char *buf, loff_t off, size_t count)
531 {
532 	uint8_t ec_byte;
533 	int ret;
534 	int i;
535 
536 	for (i = 0; i < count; i++) {
537 		ec_byte = EEPROM_START + off + i;
538 		ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &buf[i], 1);
539 		if (ret) {
540 			pr_err("olpc-battery: "
541 			       "EC_BAT_EEPROM cmd @ 0x%x failed - %d!\n",
542 			       ec_byte, ret);
543 			return -EIO;
544 		}
545 	}
546 
547 	return count;
548 }
549 
550 static struct bin_attribute olpc_bat_eeprom = {
551 	.attr = {
552 		.name = "eeprom",
553 		.mode = S_IRUGO,
554 	},
555 	.size = EEPROM_SIZE,
556 	.read = olpc_bat_eeprom_read,
557 };
558 
559 /* Allow userspace to see the specific error value pulled from the EC */
560 
561 static ssize_t olpc_bat_error_read(struct device *dev,
562 		struct device_attribute *attr, char *buf)
563 {
564 	uint8_t ec_byte;
565 	ssize_t ret;
566 
567 	ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
568 	if (ret < 0)
569 		return ret;
570 
571 	return sprintf(buf, "%d\n", ec_byte);
572 }
573 
574 static struct device_attribute olpc_bat_error = {
575 	.attr = {
576 		.name = "error",
577 		.mode = S_IRUGO,
578 	},
579 	.show = olpc_bat_error_read,
580 };
581 
582 static struct attribute *olpc_bat_sysfs_attrs[] = {
583 	&olpc_bat_error.attr,
584 	NULL
585 };
586 
587 static struct bin_attribute *olpc_bat_sysfs_bin_attrs[] = {
588 	&olpc_bat_eeprom,
589 	NULL
590 };
591 
592 static const struct attribute_group olpc_bat_sysfs_group = {
593 	.attrs = olpc_bat_sysfs_attrs,
594 	.bin_attrs = olpc_bat_sysfs_bin_attrs,
595 
596 };
597 
598 static const struct attribute_group *olpc_bat_sysfs_groups[] = {
599 	&olpc_bat_sysfs_group,
600 	NULL
601 };
602 
603 /*********************************************************************
604  *		Initialisation
605  *********************************************************************/
606 
607 static struct power_supply_desc olpc_bat_desc = {
608 	.name = "olpc_battery",
609 	.get_property = olpc_bat_get_property,
610 	.use_for_apm = 1,
611 };
612 
613 static int olpc_battery_suspend(struct platform_device *pdev,
614 				pm_message_t state)
615 {
616 	struct olpc_battery_data *data = platform_get_drvdata(pdev);
617 
618 	if (device_may_wakeup(&data->olpc_ac->dev))
619 		olpc_ec_wakeup_set(EC_SCI_SRC_ACPWR);
620 	else
621 		olpc_ec_wakeup_clear(EC_SCI_SRC_ACPWR);
622 
623 	if (device_may_wakeup(&data->olpc_bat->dev))
624 		olpc_ec_wakeup_set(EC_SCI_SRC_BATTERY | EC_SCI_SRC_BATSOC
625 				   | EC_SCI_SRC_BATERR);
626 	else
627 		olpc_ec_wakeup_clear(EC_SCI_SRC_BATTERY | EC_SCI_SRC_BATSOC
628 				     | EC_SCI_SRC_BATERR);
629 
630 	return 0;
631 }
632 
633 static int olpc_battery_probe(struct platform_device *pdev)
634 {
635 	struct power_supply_config bat_psy_cfg = {};
636 	struct power_supply_config ac_psy_cfg = {};
637 	struct olpc_battery_data *data;
638 	struct device_node *np;
639 	uint8_t status;
640 	uint8_t ecver;
641 	int ret;
642 
643 	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
644 	if (!data)
645 		return -ENOMEM;
646 	platform_set_drvdata(pdev, data);
647 
648 	/* See if the EC is already there and get the EC revision */
649 	ret = olpc_ec_cmd(EC_FIRMWARE_REV, NULL, 0, &ecver, 1);
650 	if (ret)
651 		return ret;
652 
653 	np = of_find_compatible_node(NULL, NULL, "olpc,xo1.75-ec");
654 	if (np) {
655 		of_node_put(np);
656 		/* XO 1.75 */
657 		data->new_proto = true;
658 		data->little_endian = true;
659 	} else if (ecver > 0x44) {
660 		/* XO 1 or 1.5 with a new EC firmware. */
661 		data->new_proto = true;
662 	} else if (ecver < 0x44) {
663 		/*
664 		 * We've seen a number of EC protocol changes; this driver
665 		 * requires the latest EC protocol, supported by 0x44 and above.
666 		 */
667 		printk(KERN_NOTICE "OLPC EC version 0x%02x too old for "
668 			"battery driver.\n", ecver);
669 		return -ENXIO;
670 	}
671 
672 	ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
673 	if (ret)
674 		return ret;
675 
676 	/* Ignore the status. It doesn't actually matter */
677 
678 	ac_psy_cfg.of_node = pdev->dev.of_node;
679 	ac_psy_cfg.drv_data = data;
680 
681 	data->olpc_ac = devm_power_supply_register(&pdev->dev, &olpc_ac_desc,
682 								&ac_psy_cfg);
683 	if (IS_ERR(data->olpc_ac))
684 		return PTR_ERR(data->olpc_ac);
685 
686 	if (of_device_is_compatible(pdev->dev.of_node, "olpc,xo1.5-battery")) {
687 		/* XO-1.5 */
688 		olpc_bat_desc.properties = olpc_xo15_bat_props;
689 		olpc_bat_desc.num_properties = ARRAY_SIZE(olpc_xo15_bat_props);
690 	} else {
691 		/* XO-1 */
692 		olpc_bat_desc.properties = olpc_xo1_bat_props;
693 		olpc_bat_desc.num_properties = ARRAY_SIZE(olpc_xo1_bat_props);
694 	}
695 
696 	bat_psy_cfg.of_node = pdev->dev.of_node;
697 	bat_psy_cfg.drv_data = data;
698 	bat_psy_cfg.attr_grp = olpc_bat_sysfs_groups;
699 
700 	data->olpc_bat = devm_power_supply_register(&pdev->dev, &olpc_bat_desc,
701 								&bat_psy_cfg);
702 	if (IS_ERR(data->olpc_bat))
703 		return PTR_ERR(data->olpc_bat);
704 
705 	if (olpc_ec_wakeup_available()) {
706 		device_set_wakeup_capable(&data->olpc_ac->dev, true);
707 		device_set_wakeup_capable(&data->olpc_bat->dev, true);
708 	}
709 
710 	return 0;
711 }
712 
713 static const struct of_device_id olpc_battery_ids[] = {
714 	{ .compatible = "olpc,xo1-battery" },
715 	{ .compatible = "olpc,xo1.5-battery" },
716 	{}
717 };
718 MODULE_DEVICE_TABLE(of, olpc_battery_ids);
719 
720 static struct platform_driver olpc_battery_driver = {
721 	.driver = {
722 		.name = "olpc-battery",
723 		.of_match_table = olpc_battery_ids,
724 	},
725 	.probe = olpc_battery_probe,
726 	.suspend = olpc_battery_suspend,
727 };
728 
729 module_platform_driver(olpc_battery_driver);
730 
731 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
732 MODULE_LICENSE("GPL");
733 MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");
734