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authorDavid Woodhouse <dwmw2@infradead.org>2007-05-03 16:51:18 -0400
committerDavid Woodhouse <dwmw2@infradead.org>2007-07-10 06:28:22 -0400
commitfb972873a767220333ffb509de8d9131336e212c (patch)
treebb3212e2f531be875f8c8e82bb6236ed2d975760 /drivers/power/olpc_battery.c
parentefea58e397dec84e37209c98619d39a46872db4d (diff)
[BATTERY] One Laptop Per Child power/battery driver
Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Anton Vorontsov <cbou@mail.ru>
Diffstat (limited to 'drivers/power/olpc_battery.c')
-rw-r--r--drivers/power/olpc_battery.c352
1 files changed, 352 insertions, 0 deletions
diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c
new file mode 100644
index 000000000000..878684df7667
--- /dev/null
+++ b/drivers/power/olpc_battery.c
@@ -0,0 +1,352 @@
1/*
2 * Battery driver for One Laptop Per Child board.
3 *
4 * Copyright © 2006 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/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>
17#include <asm/olpc.h>
18
19
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 */
30
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
38
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
46
47#define BAT_ADDR_MFR_TYPE 0x5F
48
49/*********************************************************************
50 * Power
51 *********************************************************************/
52
53static int olpc_ac_get_prop(struct power_supply *psy,
54 enum power_supply_property psp,
55 union power_supply_propval *val)
56{
57 int ret = 0;
58 uint8_t status;
59
60 switch (psp) {
61 case POWER_SUPPLY_PROP_ONLINE:
62 ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
63 if (ret)
64 return ret;
65
66 val->intval = !!(status & BAT_STAT_AC);
67 break;
68 default:
69 ret = -EINVAL;
70 break;
71 }
72 return ret;
73}
74
75static enum power_supply_property olpc_ac_props[] = {
76 POWER_SUPPLY_PROP_ONLINE,
77};
78
79static struct power_supply olpc_ac = {
80 .name = "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,
85};
86
87/*********************************************************************
88 * Battery properties
89 *********************************************************************/
90static int olpc_bat_get_property(struct power_supply *psy,
91 enum power_supply_property psp,
92 union power_supply_propval *val)
93{
94 int ret = 0;
95 int16_t ec_word;
96 uint8_t ec_byte;
97
98 ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &ec_byte, 1);
99 if (ret)
100 return ret;
101
102 /* Theoretically there's a race here -- the battery could be
103 removed immediately after we check whether it's present, and
104 then we query for some other property of the now-absent battery.
105 It doesn't matter though -- the EC will return the last-known
106 information, and it's as if we just ran that _little_ bit faster
107 and managed to read it out before the battery went away. */
108 if (!(ec_byte & BAT_STAT_PRESENT) && psp != POWER_SUPPLY_PROP_PRESENT)
109 return -ENODEV;
110
111 switch (psp) {
112 case POWER_SUPPLY_PROP_STATUS:
113 if (olpc_platform_info.ecver > 0x44) {
114 if (ec_byte & BAT_STAT_CHARGING)
115 val->intval = POWER_SUPPLY_STATUS_CHARGING;
116 else if (ec_byte & BAT_STAT_DISCHARGING)
117 val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
118 else if (ec_byte & BAT_STAT_FULL)
119 val->intval = POWER_SUPPLY_STATUS_FULL;
120 else /* er,... */
121 val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
122 } else {
123 /* Older EC didn't report charge/discharge bits */
124 if (!(ec_byte & BAT_STAT_AC)) /* No AC means discharging */
125 val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
126 else if (ec_byte & BAT_STAT_FULL)
127 val->intval = POWER_SUPPLY_STATUS_FULL;
128 else /* Not _necessarily_ true but EC doesn't tell all yet */
129 val->intval = POWER_SUPPLY_STATUS_CHARGING;
130 break;
131 }
132 case POWER_SUPPLY_PROP_PRESENT:
133 val->intval = !!(ec_byte & BAT_STAT_PRESENT);
134 break;
135
136 case POWER_SUPPLY_PROP_HEALTH:
137 if (ec_byte & BAT_STAT_DESTROY)
138 val->intval = POWER_SUPPLY_HEALTH_DEAD;
139 else {
140 ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
141 if (ret)
142 return ret;
143
144 switch (ec_byte) {
145 case 0:
146 val->intval = POWER_SUPPLY_HEALTH_GOOD;
147 break;
148
149 case BAT_ERR_OVERTEMP:
150 val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
151 break;
152
153 case BAT_ERR_OVERVOLTAGE:
154 val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
155 break;
156
157 case BAT_ERR_INFOFAIL:
158 case BAT_ERR_OUT_OF_CONTROL:
159 case BAT_ERR_ID_FAIL:
160 case BAT_ERR_ACR_FAIL:
161 val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
162 break;
163
164 default:
165 /* Eep. We don't know this failure code */
166 return -EIO;
167 }
168 }
169 break;
170
171 case POWER_SUPPLY_PROP_MANUFACTURER:
172 ec_byte = BAT_ADDR_MFR_TYPE;
173 ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
174 if (ret)
175 return ret;
176
177 switch (ec_byte >> 4) {
178 case 1:
179 val->strval = "Gold Peak";
180 break;
181 case 2:
182 val->strval = "BYD";
183 break;
184 default:
185 val->strval = "Unknown";
186 break;
187 }
188 break;
189 case POWER_SUPPLY_PROP_TECHNOLOGY:
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 break;
207 case POWER_SUPPLY_PROP_VOLTAGE_AVG:
208 ret = olpc_ec_cmd(EC_BAT_VOLTAGE, NULL, 0, (void *)&ec_word, 2);
209 if (ret)
210 return ret;
211
212 ec_word = be16_to_cpu(ec_word);
213 val->intval = ec_word * 9760L / 32;
214 break;
215 case POWER_SUPPLY_PROP_CURRENT_AVG:
216 ret = olpc_ec_cmd(EC_BAT_CURRENT, NULL, 0, (void *)&ec_word, 2);
217 if (ret)
218 return ret;
219
220 ec_word = be16_to_cpu(ec_word);
221 val->intval = ec_word * 15625L / 120;
222 break;
223 case POWER_SUPPLY_PROP_CAPACITY:
224 ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &ec_byte, 1);
225 if (ret)
226 return ret;
227 val->intval = ec_byte;
228 break;
229 case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
230 if (ec_byte & BAT_STAT_FULL)
231 val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
232 else if (ec_byte & BAT_STAT_LOW)
233 val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
234 else
235 val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
236 break;
237 case POWER_SUPPLY_PROP_TEMP:
238 ret = olpc_ec_cmd(EC_BAT_TEMP, NULL, 0, (void *)&ec_word, 2);
239 if (ret)
240 return ret;
241 ec_word = be16_to_cpu(ec_word);
242 val->intval = ec_word * 100 / 256;
243 break;
244 case POWER_SUPPLY_PROP_TEMP_AMBIENT:
245 ret = olpc_ec_cmd(EC_AMB_TEMP, NULL, 0, (void *)&ec_word, 2);
246 if (ret)
247 return ret;
248
249 ec_word = be16_to_cpu(ec_word);
250 val->intval = ec_word * 100 / 256;
251 break;
252 default:
253 ret = -EINVAL;
254 break;
255 }
256
257 return ret;
258}
259
260static enum power_supply_property olpc_bat_props[] = {
261 POWER_SUPPLY_PROP_STATUS,
262 POWER_SUPPLY_PROP_PRESENT,
263 POWER_SUPPLY_PROP_HEALTH,
264 POWER_SUPPLY_PROP_TECHNOLOGY,
265 POWER_SUPPLY_PROP_VOLTAGE_AVG,
266 POWER_SUPPLY_PROP_CURRENT_AVG,
267 POWER_SUPPLY_PROP_CAPACITY,
268 POWER_SUPPLY_PROP_CAPACITY_LEVEL,
269 POWER_SUPPLY_PROP_TEMP,
270 POWER_SUPPLY_PROP_TEMP_AMBIENT,
271 POWER_SUPPLY_PROP_MANUFACTURER,
272};
273
274/*********************************************************************
275 * Initialisation
276 *********************************************************************/
277
278static struct platform_device *bat_pdev;
279
280static struct power_supply olpc_bat = {
281 .properties = olpc_bat_props,
282 .num_properties = ARRAY_SIZE(olpc_bat_props),
283 .get_property = olpc_bat_get_property,
284 .use_for_apm = 1,
285};
286
287void olpc_battery_trigger_uevent(unsigned long cause)
288{
289 if (cause & EC_SCI_SRC_ACPWR)
290 kobject_uevent(&olpc_ac.dev->kobj, KOBJ_CHANGE);
291 if (cause & (EC_SCI_SRC_BATERR|EC_SCI_SRC_BATSOC|EC_SCI_SRC_BATTERY))
292 kobject_uevent(&olpc_bat.dev->kobj, KOBJ_CHANGE);
293}
294
295static int __init olpc_bat_init(void)
296{
297 int ret = 0;
298 uint8_t status;
299
300 if (!olpc_platform_info.ecver)
301 return -ENXIO;
302 if (olpc_platform_info.ecver < 0x43) {
303 printk(KERN_NOTICE "OLPC EC version 0x%02x too old for battery driver.\n", olpc_platform_info.ecver);
304 return -ENXIO;
305 }
306
307 ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
308 if (ret)
309 return ret;
310
311 /* Ignore the status. It doesn't actually matter */
312
313 bat_pdev = platform_device_register_simple("olpc-battery", 0, NULL, 0);
314 if (IS_ERR(bat_pdev))
315 return PTR_ERR(bat_pdev);
316
317 ret = power_supply_register(&bat_pdev->dev, &olpc_ac);
318 if (ret)
319 goto ac_failed;
320
321 olpc_bat.name = bat_pdev->name;
322
323 ret = power_supply_register(&bat_pdev->dev, &olpc_bat);
324 if (ret)
325 goto battery_failed;
326
327 olpc_register_battery_callback(&olpc_battery_trigger_uevent);
328 goto success;
329
330battery_failed:
331 power_supply_unregister(&olpc_ac);
332ac_failed:
333 platform_device_unregister(bat_pdev);
334success:
335 return ret;
336}
337
338static void __exit olpc_bat_exit(void)
339{
340 olpc_deregister_battery_callback();
341 power_supply_unregister(&olpc_bat);
342 power_supply_unregister(&olpc_ac);
343 platform_device_unregister(bat_pdev);
344 return;
345}
346
347module_init(olpc_bat_init);
348module_exit(olpc_bat_exit);
349
350MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
351MODULE_LICENSE("GPL");
352MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");