2 * Battery driver for One Laptop Per Child board.
4 * Copyright © 2006 David Woodhouse <dwmw2@infradead.org>
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.
11 #include <linux/module.h>
12 #include <linux/err.h>
13 #include <linux/platform_device.h>
14 #include <linux/power_supply.h>
15 #include <linux/jiffies.h>
16 #include <linux/sched.h>
20 #define EC_BAT_VOLTAGE 0x10 /* uint16_t, *9.76/32, mV */
21 #define EC_BAT_CURRENT 0x11 /* int16_t, *15.625/120, mA */
22 #define EC_BAT_ACR 0x12
23 #define EC_BAT_TEMP 0x13 /* uint16_t, *100/256, °C */
24 #define EC_AMB_TEMP 0x14 /* uint16_t, *100/256, °C */
25 #define EC_BAT_STATUS 0x15 /* uint8_t, bitmask */
26 #define EC_BAT_SOC 0x16 /* uint8_t, percentage */
27 #define EC_BAT_SERIAL 0x17 /* uint8_t[6] */
28 #define EC_BAT_EEPROM 0x18 /* uint8_t adr as input, uint8_t output */
29 #define EC_BAT_ERRCODE 0x1f /* uint8_t, bitmask */
31 #define BAT_STAT_PRESENT 0x01
32 #define BAT_STAT_FULL 0x02
33 #define BAT_STAT_LOW 0x04
34 #define BAT_STAT_DESTROY 0x08
35 #define BAT_STAT_AC 0x10
36 #define BAT_STAT_CHARGING 0x20
37 #define BAT_STAT_DISCHARGING 0x40
39 #define BAT_ERR_INFOFAIL 0x02
40 #define BAT_ERR_OVERVOLTAGE 0x04
41 #define BAT_ERR_OVERTEMP 0x05
42 #define BAT_ERR_GAUGESTOP 0x06
43 #define BAT_ERR_OUT_OF_CONTROL 0x07
44 #define BAT_ERR_ID_FAIL 0x09
45 #define BAT_ERR_ACR_FAIL 0x10
47 #define BAT_ADDR_MFR_TYPE 0x5F
49 /*********************************************************************
51 *********************************************************************/
53 static int olpc_ac_get_prop(struct power_supply *psy,
54 enum power_supply_property psp,
55 union power_supply_propval *val)
61 case POWER_SUPPLY_PROP_ONLINE:
62 ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
66 val->intval = !!(status & BAT_STAT_AC);
75 static enum power_supply_property olpc_ac_props[] = {
76 POWER_SUPPLY_PROP_ONLINE,
79 static struct power_supply olpc_ac = {
81 .type = POWER_SUPPLY_TYPE_MAINS,
82 .properties = olpc_ac_props,
83 .num_properties = ARRAY_SIZE(olpc_ac_props),
84 .get_property = olpc_ac_get_prop,
87 static char bat_serial[17]; /* Ick */
89 /*********************************************************************
91 *********************************************************************/
92 static int olpc_bat_get_property(struct power_supply *psy,
93 enum power_supply_property psp,
94 union power_supply_propval *val)
101 ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &ec_byte, 1);
105 /* Theoretically there's a race here -- the battery could be
106 removed immediately after we check whether it's present, and
107 then we query for some other property of the now-absent battery.
108 It doesn't matter though -- the EC will return the last-known
109 information, and it's as if we just ran that _little_ bit faster
110 and managed to read it out before the battery went away. */
111 if (!(ec_byte & BAT_STAT_PRESENT) && psp != POWER_SUPPLY_PROP_PRESENT)
115 case POWER_SUPPLY_PROP_STATUS:
116 if (olpc_platform_info.ecver > 0x44) {
117 if (ec_byte & BAT_STAT_CHARGING)
118 val->intval = POWER_SUPPLY_STATUS_CHARGING;
119 else if (ec_byte & BAT_STAT_DISCHARGING)
120 val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
121 else if (ec_byte & BAT_STAT_FULL)
122 val->intval = POWER_SUPPLY_STATUS_FULL;
124 val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
126 /* Older EC didn't report charge/discharge bits */
127 if (!(ec_byte & BAT_STAT_AC)) /* No AC means discharging */
128 val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
129 else if (ec_byte & BAT_STAT_FULL)
130 val->intval = POWER_SUPPLY_STATUS_FULL;
131 else /* Not _necessarily_ true but EC doesn't tell all yet */
132 val->intval = POWER_SUPPLY_STATUS_CHARGING;
135 case POWER_SUPPLY_PROP_PRESENT:
136 val->intval = !!(ec_byte & BAT_STAT_PRESENT);
139 case POWER_SUPPLY_PROP_HEALTH:
140 if (ec_byte & BAT_STAT_DESTROY)
141 val->intval = POWER_SUPPLY_HEALTH_DEAD;
143 ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
149 val->intval = POWER_SUPPLY_HEALTH_GOOD;
152 case BAT_ERR_OVERTEMP:
153 val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
156 case BAT_ERR_OVERVOLTAGE:
157 val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
160 case BAT_ERR_INFOFAIL:
161 case BAT_ERR_OUT_OF_CONTROL:
162 case BAT_ERR_ID_FAIL:
163 case BAT_ERR_ACR_FAIL:
164 val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
168 /* Eep. We don't know this failure code */
174 case POWER_SUPPLY_PROP_MANUFACTURER:
175 ec_byte = BAT_ADDR_MFR_TYPE;
176 ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
180 switch (ec_byte >> 4) {
182 val->strval = "Gold Peak";
188 val->strval = "Unknown";
192 case POWER_SUPPLY_PROP_TECHNOLOGY:
193 ec_byte = BAT_ADDR_MFR_TYPE;
194 ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
198 switch (ec_byte & 0xf) {
200 val->intval = POWER_SUPPLY_TECHNOLOGY_NiMH;
203 val->intval = POWER_SUPPLY_TECHNOLOGY_LiFe;
206 val->intval = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
210 case POWER_SUPPLY_PROP_VOLTAGE_AVG:
211 ret = olpc_ec_cmd(EC_BAT_VOLTAGE, NULL, 0, (void *)&ec_word, 2);
215 ec_word = be16_to_cpu(ec_word);
216 val->intval = ec_word * 9760L / 32;
218 case POWER_SUPPLY_PROP_CURRENT_AVG:
219 ret = olpc_ec_cmd(EC_BAT_CURRENT, NULL, 0, (void *)&ec_word, 2);
223 ec_word = be16_to_cpu(ec_word);
224 val->intval = ec_word * 15625L / 120;
226 case POWER_SUPPLY_PROP_CAPACITY:
227 ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &ec_byte, 1);
230 val->intval = ec_byte;
232 case POWER_SUPPLY_PROP_TEMP:
233 ret = olpc_ec_cmd(EC_BAT_TEMP, NULL, 0, (void *)&ec_word, 2);
236 ec_word = be16_to_cpu(ec_word);
237 val->intval = ec_word * 100 / 256;
239 case POWER_SUPPLY_PROP_TEMP_AMBIENT:
240 ret = olpc_ec_cmd(EC_AMB_TEMP, NULL, 0, (void *)&ec_word, 2);
244 ec_word = be16_to_cpu(ec_word);
245 val->intval = ec_word * 100 / 256;
247 case POWER_SUPPLY_PROP_SERIAL_NUMBER:
248 ret = olpc_ec_cmd(EC_BAT_SERIAL, NULL, 0, (void *)&ser_buf, 8);
252 sprintf(bat_serial, "%016llx", (long long)be64_to_cpu(ser_buf));
253 val->strval = bat_serial;
263 static enum power_supply_property olpc_bat_props[] = {
264 POWER_SUPPLY_PROP_STATUS,
265 POWER_SUPPLY_PROP_PRESENT,
266 POWER_SUPPLY_PROP_HEALTH,
267 POWER_SUPPLY_PROP_TECHNOLOGY,
268 POWER_SUPPLY_PROP_VOLTAGE_AVG,
269 POWER_SUPPLY_PROP_CURRENT_AVG,
270 POWER_SUPPLY_PROP_CAPACITY,
271 POWER_SUPPLY_PROP_TEMP,
272 POWER_SUPPLY_PROP_TEMP_AMBIENT,
273 POWER_SUPPLY_PROP_MANUFACTURER,
274 POWER_SUPPLY_PROP_SERIAL_NUMBER,
277 /*********************************************************************
279 *********************************************************************/
281 static struct platform_device *bat_pdev;
283 static struct power_supply olpc_bat = {
284 .properties = olpc_bat_props,
285 .num_properties = ARRAY_SIZE(olpc_bat_props),
286 .get_property = olpc_bat_get_property,
290 void olpc_battery_trigger_uevent(unsigned long cause)
292 if (cause & EC_SCI_SRC_ACPWR)
293 kobject_uevent(&olpc_ac.dev->kobj, KOBJ_CHANGE);
294 if (cause & (EC_SCI_SRC_BATERR|EC_SCI_SRC_BATSOC|EC_SCI_SRC_BATTERY))
295 kobject_uevent(&olpc_bat.dev->kobj, KOBJ_CHANGE);
298 static int __init olpc_bat_init(void)
303 if (!olpc_platform_info.ecver)
305 if (olpc_platform_info.ecver < 0x43) {
306 printk(KERN_NOTICE "OLPC EC version 0x%02x too old for battery driver.\n", olpc_platform_info.ecver);
310 ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
314 /* Ignore the status. It doesn't actually matter */
316 bat_pdev = platform_device_register_simple("olpc-battery", 0, NULL, 0);
317 if (IS_ERR(bat_pdev))
318 return PTR_ERR(bat_pdev);
320 ret = power_supply_register(&bat_pdev->dev, &olpc_ac);
324 olpc_bat.name = bat_pdev->name;
326 ret = power_supply_register(&bat_pdev->dev, &olpc_bat);
333 power_supply_unregister(&olpc_ac);
335 platform_device_unregister(bat_pdev);
340 static void __exit olpc_bat_exit(void)
342 power_supply_unregister(&olpc_bat);
343 power_supply_unregister(&olpc_ac);
344 platform_device_unregister(bat_pdev);
347 module_init(olpc_bat_init);
348 module_exit(olpc_bat_exit);
350 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
351 MODULE_LICENSE("GPL");
352 MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");