xref: /linux/drivers/power/supply/apm_power.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942) 
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 = class_for_each_device(power_supply_class, NULL, &bp,
83 				      __find_main_battery);
84 	if (error) {
85 		main_battery = bp.main;
86 		return;
87 	}
88 
89 	if ((bp.max_energy_bat && bp.max_charge_bat) &&
90 			(bp.max_energy_bat != bp.max_charge_bat)) {
91 		/* try guess battery with more capacity */
92 		if (!PSY_PROP(bp.max_charge_bat, VOLTAGE_MAX_DESIGN,
93 			      &bp.full)) {
94 			if (bp.max_energy > bp.max_charge * bp.full.intval)
95 				main_battery = bp.max_energy_bat;
96 			else
97 				main_battery = bp.max_charge_bat;
98 		} else if (!PSY_PROP(bp.max_energy_bat, VOLTAGE_MAX_DESIGN,
99 								  &bp.full)) {
100 			if (bp.max_charge > bp.max_energy / bp.full.intval)
101 				main_battery = bp.max_charge_bat;
102 			else
103 				main_battery = bp.max_energy_bat;
104 		} else {
105 			/* give up, choice any */
106 			main_battery = bp.max_energy_bat;
107 		}
108 	} else if (bp.max_charge_bat) {
109 		main_battery = bp.max_charge_bat;
110 	} else if (bp.max_energy_bat) {
111 		main_battery = bp.max_energy_bat;
112 	} else {
113 		/* give up, try the last if any */
114 		main_battery = bp.bat;
115 	}
116 }
117 
118 static int do_calculate_time(int status, enum apm_source source)
119 {
120 	union power_supply_propval full;
121 	union power_supply_propval empty;
122 	union power_supply_propval cur;
123 	union power_supply_propval I;
124 	enum power_supply_property full_prop;
125 	enum power_supply_property full_design_prop;
126 	enum power_supply_property empty_prop;
127 	enum power_supply_property empty_design_prop;
128 	enum power_supply_property cur_avg_prop;
129 	enum power_supply_property cur_now_prop;
130 
131 	if (MPSY_PROP(CURRENT_AVG, &I)) {
132 		/* if battery can't report average value, use momentary */
133 		if (MPSY_PROP(CURRENT_NOW, &I))
134 			return -1;
135 	}
136 
137 	if (!I.intval)
138 		return 0;
139 
140 	switch (source) {
141 	case SOURCE_CHARGE:
142 		full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
143 		full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
144 		empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
145 		empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
146 		cur_avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
147 		cur_now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
148 		break;
149 	case SOURCE_ENERGY:
150 		full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
151 		full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
152 		empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
153 		empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
154 		cur_avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
155 		cur_now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
156 		break;
157 	case SOURCE_VOLTAGE:
158 		full_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX;
159 		full_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN;
160 		empty_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN;
161 		empty_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN;
162 		cur_avg_prop = POWER_SUPPLY_PROP_VOLTAGE_AVG;
163 		cur_now_prop = POWER_SUPPLY_PROP_VOLTAGE_NOW;
164 		break;
165 	default:
166 		printk(KERN_ERR "Unsupported source: %d\n", source);
167 		return -1;
168 	}
169 
170 	if (_MPSY_PROP(full_prop, &full)) {
171 		/* if battery can't report this property, use design value */
172 		if (_MPSY_PROP(full_design_prop, &full))
173 			return -1;
174 	}
175 
176 	if (_MPSY_PROP(empty_prop, &empty)) {
177 		/* if battery can't report this property, use design value */
178 		if (_MPSY_PROP(empty_design_prop, &empty))
179 			empty.intval = 0;
180 	}
181 
182 	if (_MPSY_PROP(cur_avg_prop, &cur)) {
183 		/* if battery can't report average value, use momentary */
184 		if (_MPSY_PROP(cur_now_prop, &cur))
185 			return -1;
186 	}
187 
188 	if (status == POWER_SUPPLY_STATUS_CHARGING)
189 		return ((cur.intval - full.intval) * 60L) / I.intval;
190 	else
191 		return -((cur.intval - empty.intval) * 60L) / I.intval;
192 }
193 
194 static int calculate_time(int status)
195 {
196 	int time;
197 
198 	time = do_calculate_time(status, SOURCE_ENERGY);
199 	if (time != -1)
200 		return time;
201 
202 	time = do_calculate_time(status, SOURCE_CHARGE);
203 	if (time != -1)
204 		return time;
205 
206 	time = do_calculate_time(status, SOURCE_VOLTAGE);
207 	if (time != -1)
208 		return time;
209 
210 	return -1;
211 }
212 
213 static int calculate_capacity(enum apm_source source)
214 {
215 	enum power_supply_property full_prop, empty_prop;
216 	enum power_supply_property full_design_prop, empty_design_prop;
217 	enum power_supply_property now_prop, avg_prop;
218 	union power_supply_propval empty, full, cur;
219 	int ret;
220 
221 	switch (source) {
222 	case SOURCE_CHARGE:
223 		full_prop = POWER_SUPPLY_PROP_CHARGE_FULL;
224 		empty_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY;
225 		full_design_prop = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN;
226 		empty_design_prop = POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN;
227 		now_prop = POWER_SUPPLY_PROP_CHARGE_NOW;
228 		avg_prop = POWER_SUPPLY_PROP_CHARGE_AVG;
229 		break;
230 	case SOURCE_ENERGY:
231 		full_prop = POWER_SUPPLY_PROP_ENERGY_FULL;
232 		empty_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY;
233 		full_design_prop = POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN;
234 		empty_design_prop = POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN;
235 		now_prop = POWER_SUPPLY_PROP_ENERGY_NOW;
236 		avg_prop = POWER_SUPPLY_PROP_ENERGY_AVG;
237 		break;
238 	case SOURCE_VOLTAGE:
239 		full_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX;
240 		empty_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN;
241 		full_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN;
242 		empty_design_prop = POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN;
243 		now_prop = POWER_SUPPLY_PROP_VOLTAGE_NOW;
244 		avg_prop = POWER_SUPPLY_PROP_VOLTAGE_AVG;
245 		break;
246 	default:
247 		printk(KERN_ERR "Unsupported source: %d\n", source);
248 		return -1;
249 	}
250 
251 	if (_MPSY_PROP(full_prop, &full)) {
252 		/* if battery can't report this property, use design value */
253 		if (_MPSY_PROP(full_design_prop, &full))
254 			return -1;
255 	}
256 
257 	if (_MPSY_PROP(avg_prop, &cur)) {
258 		/* if battery can't report average value, use momentary */
259 		if (_MPSY_PROP(now_prop, &cur))
260 			return -1;
261 	}
262 
263 	if (_MPSY_PROP(empty_prop, &empty)) {
264 		/* if battery can't report this property, use design value */
265 		if (_MPSY_PROP(empty_design_prop, &empty))
266 			empty.intval = 0;
267 	}
268 
269 	if (full.intval - empty.intval)
270 		ret =  ((cur.intval - empty.intval) * 100L) /
271 		       (full.intval - empty.intval);
272 	else
273 		return -1;
274 
275 	if (ret > 100)
276 		return 100;
277 	else if (ret < 0)
278 		return 0;
279 
280 	return ret;
281 }
282 
283 static void apm_battery_apm_get_power_status(struct apm_power_info *info)
284 {
285 	union power_supply_propval status;
286 	union power_supply_propval capacity, time_to_full, time_to_empty;
287 
288 	mutex_lock(&apm_mutex);
289 	find_main_battery();
290 	if (!main_battery) {
291 		mutex_unlock(&apm_mutex);
292 		return;
293 	}
294 
295 	/* status */
296 
297 	if (MPSY_PROP(STATUS, &status))
298 		status.intval = POWER_SUPPLY_STATUS_UNKNOWN;
299 
300 	/* ac line status */
301 
302 	if ((status.intval == POWER_SUPPLY_STATUS_CHARGING) ||
303 	    (status.intval == POWER_SUPPLY_STATUS_NOT_CHARGING) ||
304 	    (status.intval == POWER_SUPPLY_STATUS_FULL))
305 		info->ac_line_status = APM_AC_ONLINE;
306 	else
307 		info->ac_line_status = APM_AC_OFFLINE;
308 
309 	/* battery life (i.e. capacity, in percents) */
310 
311 	if (MPSY_PROP(CAPACITY, &capacity) == 0) {
312 		info->battery_life = capacity.intval;
313 	} else {
314 		/* try calculate using energy */
315 		info->battery_life = calculate_capacity(SOURCE_ENERGY);
316 		/* if failed try calculate using charge instead */
317 		if (info->battery_life == -1)
318 			info->battery_life = calculate_capacity(SOURCE_CHARGE);
319 		if (info->battery_life == -1)
320 			info->battery_life = calculate_capacity(SOURCE_VOLTAGE);
321 	}
322 
323 	/* charging status */
324 
325 	if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
326 		info->battery_status = APM_BATTERY_STATUS_CHARGING;
327 	} else {
328 		if (info->battery_life > 50)
329 			info->battery_status = APM_BATTERY_STATUS_HIGH;
330 		else if (info->battery_life > 5)
331 			info->battery_status = APM_BATTERY_STATUS_LOW;
332 		else
333 			info->battery_status = APM_BATTERY_STATUS_CRITICAL;
334 	}
335 	info->battery_flag = info->battery_status;
336 
337 	/* time */
338 
339 	info->units = APM_UNITS_MINS;
340 
341 	if (status.intval == POWER_SUPPLY_STATUS_CHARGING) {
342 		if (!MPSY_PROP(TIME_TO_FULL_AVG, &time_to_full) ||
343 				!MPSY_PROP(TIME_TO_FULL_NOW, &time_to_full))
344 			info->time = time_to_full.intval / 60;
345 		else
346 			info->time = calculate_time(status.intval);
347 	} else {
348 		if (!MPSY_PROP(TIME_TO_EMPTY_AVG, &time_to_empty) ||
349 			      !MPSY_PROP(TIME_TO_EMPTY_NOW, &time_to_empty))
350 			info->time = time_to_empty.intval / 60;
351 		else
352 			info->time = calculate_time(status.intval);
353 	}
354 
355 	mutex_unlock(&apm_mutex);
356 }
357 
358 static int __init apm_battery_init(void)
359 {
360 	printk(KERN_INFO "APM Battery Driver\n");
361 
362 	apm_get_power_status = apm_battery_apm_get_power_status;
363 	return 0;
364 }
365 
366 static void __exit apm_battery_exit(void)
367 {
368 	apm_get_power_status = NULL;
369 }
370 
371 module_init(apm_battery_init);
372 module_exit(apm_battery_exit);
373 
374 MODULE_AUTHOR("Eugeny Boger <eugenyboger@dgap.mipt.ru>");
375 MODULE_DESCRIPTION("APM emulation driver for battery monitoring class");
376 MODULE_LICENSE("GPL");
377