xref: /linux/drivers/power/supply/apm_power.c (revision 6a4aee277740d04ac0fd54cfa17cc28261932ddc) 
1 /*
2  * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
3  * Copyright © 2007 Eugeny Boger <eugenyboger@dgap.mipt.ru>
4  *
5  * Author: Eugeny Boger <eugenyboger@dgap.mipt.ru>
6  *
7  * Use consistent with the GNU GPL is permitted,
8  * provided that this copyright notice is
9  * preserved in its entirety in all copies and derived works.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/power_supply.h>
15 #include <linux/apm-emulation.h>
16 
17 
18 #define PSY_PROP(psy, prop, val) (power_supply_get_property(psy, \
19 			 POWER_SUPPLY_PROP_##prop, val))
20 
21 #define _MPSY_PROP(prop, val) (power_supply_get_property(main_battery, \
22 							 prop, val))
23 
24 #define MPSY_PROP(prop, val) _MPSY_PROP(POWER_SUPPLY_PROP_##prop, val)
25 
26 static DEFINE_MUTEX(apm_mutex);
27 static struct power_supply *main_battery;
28 
29 enum apm_source {
30 	SOURCE_ENERGY,
31 	SOURCE_CHARGE,
32 	SOURCE_VOLTAGE,
33 };
34 
35 struct find_bat_param {
36 	struct power_supply *main;
37 	struct power_supply *bat;
38 	struct power_supply *max_charge_bat;
39 	struct power_supply *max_energy_bat;
40 	union power_supply_propval full;
41 	int max_charge;
42 	int max_energy;
43 };
44 
45 static int __find_main_battery(struct device *dev, void *data)
46 {
47 	struct find_bat_param *bp = (struct find_bat_param *)data;
48 
49 	bp->bat = dev_get_drvdata(dev);
50 
51 	if (bp->bat->desc->use_for_apm) {
52 		/* nice, we explicitly asked to report this battery. */
53 		bp->main = bp->bat;
54 		return 1;
55 	}
56 
57 	if (!PSY_PROP(bp->bat, CHARGE_FULL_DESIGN, &bp->full) ||
58 			!PSY_PROP(bp->bat, CHARGE_FULL, &bp->full)) {
59 		if (bp->full.intval > bp->max_charge) {
60 			bp->max_charge_bat = bp->bat;
61 			bp->max_charge = bp->full.intval;
62 		}
63 	} else if (!PSY_PROP(bp->bat, ENERGY_FULL_DESIGN, &bp->full) ||
64 			!PSY_PROP(bp->bat, ENERGY_FULL, &bp->full)) {
65 		if (bp->full.intval > bp->max_energy) {
66 			bp->max_energy_bat = bp->bat;
67 			bp->max_energy = bp->full.intval;
68 		}
69 	}
70 	return 0;
71 }
72 
73 static void find_main_battery(void)
74 {
75 	struct find_bat_param bp;
76 	int error;
77 
78 	memset(&bp, 0, sizeof(struct find_bat_param));
79 	main_battery = NULL;
80 	bp.main = main_battery;
81 
82 	error = power_supply_for_each_device(&bp, __find_main_battery);
83 	if (error) {
84 		main_battery = bp.main;
85 		return;
86 	}
87 
88 	if ((bp.max_energy_bat && bp.max_charge_bat) &&
89 			(bp.max_energy_bat != bp.max_charge_bat)) {
90 		/* try guess battery with more capacity */
91 		if (!PSY_PROP(bp.max_charge_bat, VOLTAGE_MAX_DESIGN,
92 			      &bp.full)) {
93 			if (bp.max_energy > bp.max_charge * bp.full.intval)
94 				main_battery = bp.max_energy_bat;
95 			else
96 				main_battery = bp.max_charge_bat;
97 		} else if (!PSY_PROP(bp.max_energy_bat, VOLTAGE_MAX_DESIGN,
98 								  &bp.full)) {
99 			if (bp.max_charge > bp.max_energy / bp.full.intval)
100 				main_battery = bp.max_charge_bat;
101 			else
102 				main_battery = bp.max_energy_bat;
103 		} else {
104 			/* give up, choice any */
105 			main_battery = bp.max_energy_bat;
106 		}
107 	} else if (bp.max_charge_bat) {
108 		main_battery = bp.max_charge_bat;
109 	} else if (bp.max_energy_bat) {
110 		main_battery = bp.max_energy_bat;
111 	} else {
112 		/* give up, try the last if any */
113 		main_battery = bp.bat;
114 	}
115 }
116 
117 static int do_calculate_time(int status, enum apm_source source)
118 {
119 	union power_supply_propval full;
120 	union power_supply_propval empty;
121 	union power_supply_propval cur;
122 	union power_supply_propval I;
123 	enum power_supply_property full_prop;
124 	enum power_supply_property full_design_prop;
125 	enum power_supply_property empty_prop;
126 	enum power_supply_property empty_design_prop;
127 	enum power_supply_property cur_avg_prop;
128 	enum power_supply_property cur_now_prop;
129 
130 	if (MPSY_PROP(CURRENT_AVG, &I)) {
131 		/* if battery can't report average value, use momentary */
132 		if (MPSY_PROP(CURRENT_NOW, &I))
133 			return -1;
134 	}
135 
136 	if (!I.intval)
137 		return 0;
138 
139 	switch (source) {
140 	case SOURCE_CHARGE:
141 		full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
142 		full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
143 		empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
144 		empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
145 		cur_avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
146 		cur_now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
147 		break;
148 	case SOURCE_ENERGY:
149 		full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
150 		full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
151 		empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
152 		empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
153 		cur_avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
154 		cur_now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
155 		break;
156 	case SOURCE_VOLTAGE:
157 		full_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX;
158 		full_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN;
159 		empty_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN;
160 		empty_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN;
161 		cur_avg_prop = POWER_SUPPLY_PROP_VOLTAGE_AVG;
162 		cur_now_prop = POWER_SUPPLY_PROP_VOLTAGE_NOW;
163 		break;
164 	default:
165 		printk(KERN_ERR "Unsupported source: %d\n", source);
166 		return -1;
167 	}
168 
169 	if (_MPSY_PROP(full_prop, &full)) {
170 		/* if battery can't report this property, use design value */
171 		if (_MPSY_PROP(full_design_prop, &full))
172 			return -1;
173 	}
174 
175 	if (_MPSY_PROP(empty_prop, &empty)) {
176 		/* if battery can't report this property, use design value */
177 		if (_MPSY_PROP(empty_design_prop, &empty))
178 			empty.intval = 0;
179 	}
180 
181 	if (_MPSY_PROP(cur_avg_prop, &cur)) {
182 		/* if battery can't report average value, use momentary */
183 		if (_MPSY_PROP(cur_now_prop, &cur))
184 			return -1;
185 	}
186 
187 	if (status == POWER_SUPPLY_STATUS_CHARGING)
188 		return ((cur.intval - full.intval) * 60L) / I.intval;
189 	else
190 		return -((cur.intval - empty.intval) * 60L) / I.intval;
191 }
192 
193 static int calculate_time(int status)
194 {
195 	int time;
196 
197 	time = do_calculate_time(status, SOURCE_ENERGY);
198 	if (time != -1)
199 		return time;
200 
201 	time = do_calculate_time(status, SOURCE_CHARGE);
202 	if (time != -1)
203 		return time;
204 
205 	time = do_calculate_time(status, SOURCE_VOLTAGE);
206 	if (time != -1)
207 		return time;
208 
209 	return -1;
210 }
211 
212 static int calculate_capacity(enum apm_source source)
213 {
214 	enum power_supply_property full_prop, empty_prop;
215 	enum power_supply_property full_design_prop, empty_design_prop;
216 	enum power_supply_property now_prop, avg_prop;
217 	union power_supply_propval empty, full, cur;
218 	int ret;
219 
220 	switch (source) {
221 	case SOURCE_CHARGE:
222 		full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
223 		empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
224 		full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
225 		empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN;
226 		now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
227 		avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
228 		break;
229 	case SOURCE_ENERGY:
230 		full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
231 		empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
232 		full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
233 		empty_design_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN;
234 		now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
235 		avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
236 		break;
237 	case SOURCE_VOLTAGE:
238 		full_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX;
239 		empty_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN;
240 		full_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN;
241 		empty_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN;
242 		now_prop = POWER_SUPPLY_PROP_VOLTAGE_NOW;
243 		avg_prop = POWER_SUPPLY_PROP_VOLTAGE_AVG;
244 		break;
245 	default:
246 		printk(KERN_ERR "Unsupported source: %d\n", source);
247 		return -1;
248 	}
249 
250 	if (_MPSY_PROP(full_prop, &full)) {
251 		/* if battery can't report this property, use design value */
252 		if (_MPSY_PROP(full_design_prop, &full))
253 			return -1;
254 	}
255 
256 	if (_MPSY_PROP(avg_prop, &cur)) {
257 		/* if battery can't report average value, use momentary */
258 		if (_MPSY_PROP(now_prop, &cur))
259 			return -1;
260 	}
261 
262 	if (_MPSY_PROP(empty_prop, &empty)) {
263 		/* if battery can't report this property, use design value */
264 		if (_MPSY_PROP(empty_design_prop, &empty))
265 			empty.intval = 0;
266 	}
267 
268 	if (full.intval - empty.intval)
269 		ret =  ((cur.intval - empty.intval) * 100L) /
270 		       (full.intval - empty.intval);
271 	else
272 		return -1;
273 
274 	if (ret > 100)
275 		return 100;
276 	else if (ret < 0)
277 		return 0;
278 
279 	return ret;
280 }
281 
282 static void apm_battery_apm_get_power_status(struct apm_power_info *info)
283 {
284 	union power_supply_propval status;
285 	union power_supply_propval capacity, time_to_full, time_to_empty;
286 
287 	mutex_lock(&apm_mutex);
288 	find_main_battery();
289 	if (!main_battery) {
290 		mutex_unlock(&apm_mutex);
291 		return;
292 	}
293 
294 	/* status */
295 
296 	if (MPSY_PROP(STATUS, &status))
297 		status.intval = POWER_SUPPLY_STATUS_UNKNOWN;
298 
299 	/* ac line status */
300 
301 	if ((status.intval == POWER_SUPPLY_STATUS_CHARGING) ||
302 	    (status.intval == POWER_SUPPLY_STATUS_NOT_CHARGING) ||
303 	    (status.intval == POWER_SUPPLY_STATUS_FULL))
304 		info->ac_line_status = APM_AC_ONLINE;
305 	else
306 		info->ac_line_status = APM_AC_OFFLINE;
307 
308 	/* battery life (i.e. capacity, in percents) */
309 
310 	if (MPSY_PROP(CAPACITY, &capacity) == 0) {
311 		info->battery_life = capacity.intval;
312 	} else {
313 		/* try calculate using energy */
314 		info->battery_life = calculate_capacity(SOURCE_ENERGY);
315 		/* if failed try calculate using charge instead */
316 		if (info->battery_life == -1)
317 			info->battery_life = calculate_capacity(SOURCE_CHARGE);
318 		if (info->battery_life == -1)
319 			info->battery_life = calculate_capacity(SOURCE_VOLTAGE);
320 	}
321 
322 	/* charging status */
323 
324 	if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
325 		info->battery_status = APM_BATTERY_STATUS_CHARGING;
326 	} else {
327 		if (info->battery_life > 50)
328 			info->battery_status = APM_BATTERY_STATUS_HIGH;
329 		else if (info->battery_life > 5)
330 			info->battery_status = APM_BATTERY_STATUS_LOW;
331 		else
332 			info->battery_status = APM_BATTERY_STATUS_CRITICAL;
333 	}
334 	info->battery_flag = info->battery_status;
335 
336 	/* time */
337 
338 	info->units = APM_UNITS_MINS;
339 
340 	if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
341 		if (!MPSY_PROP(TIME_TO_FULL_AVG, &time_to_full) ||
342 				!MPSY_PROP(TIME_TO_FULL_NOW, &time_to_full))
343 			info->time = time_to_full.intval / 60;
344 		else
345 			info->time = calculate_time(status.intval);
346 	} else {
347 		if (!MPSY_PROP(TIME_TO_EMPTY_AVG, &time_to_empty) ||
348 			      !MPSY_PROP(TIME_TO_EMPTY_NOW, &time_to_empty))
349 			info->time = time_to_empty.intval / 60;
350 		else
351 			info->time = calculate_time(status.intval);
352 	}
353 
354 	mutex_unlock(&apm_mutex);
355 }
356 
357 static int __init apm_battery_init(void)
358 {
359 	printk(KERN_INFO "APM Battery Driver\n");
360 
361 	apm_get_power_status = apm_battery_apm_get_power_status;
362 	return 0;
363 }
364 
365 static void __exit apm_battery_exit(void)
366 {
367 	apm_get_power_status = NULL;
368 }
369 
370 module_init(apm_battery_init);
371 module_exit(apm_battery_exit);
372 
373 MODULE_AUTHOR("Eugeny Boger <eugenyboger@dgap.mipt.ru>");
374 MODULE_DESCRIPTION("APM emulation driver for battery monitoring class");
375 MODULE_LICENSE("GPL");
376