1 /*
2 * Common power driver for PDAs and phones with one or two external
3 * power supplies (AC/USB) connected to main and backup batteries,
4 * and optional builtin charger.
5 *
6 * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/interrupt.h>
16 #include <linux/power_supply.h>
17 #include <linux/pda_power.h>
18 #include <linux/timer.h>
19 #include <linux/jiffies.h>
20
get_irq_flags(struct resource * res)21 static inline unsigned int get_irq_flags(struct resource *res)
22 {
23 unsigned int flags = IRQF_SAMPLE_RANDOM | IRQF_SHARED;
24
25 flags |= res->flags & IRQF_TRIGGER_MASK;
26
27 return flags;
28 }
29
30 static struct device *dev;
31 static struct pda_power_pdata *pdata;
32 static struct resource *ac_irq, *usb_irq;
33 static struct timer_list charger_timer;
34 static struct timer_list supply_timer;
35 static struct timer_list polling_timer;
36 static int polling;
37
38 enum {
39 PDA_PSY_OFFLINE = 0,
40 PDA_PSY_ONLINE = 1,
41 PDA_PSY_TO_CHANGE,
42 };
43 static int new_ac_status = -1;
44 static int new_usb_status = -1;
45 static int ac_status = -1;
46 static int usb_status = -1;
47
pda_power_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)48 static int pda_power_get_property(struct power_supply *psy,
49 enum power_supply_property psp,
50 union power_supply_propval *val)
51 {
52 switch (psp) {
53 case POWER_SUPPLY_PROP_ONLINE:
54 if (psy->type == POWER_SUPPLY_TYPE_MAINS)
55 val->intval = pdata->is_ac_online ?
56 pdata->is_ac_online() : 0;
57 else
58 val->intval = pdata->is_usb_online ?
59 pdata->is_usb_online() : 0;
60 break;
61 default:
62 return -EINVAL;
63 }
64 return 0;
65 }
66
67 static enum power_supply_property pda_power_props[] = {
68 POWER_SUPPLY_PROP_ONLINE,
69 };
70
71 static char *pda_power_supplied_to[] = {
72 "main-battery",
73 "backup-battery",
74 };
75
76 static struct power_supply pda_psy_ac = {
77 .name = "ac",
78 .type = POWER_SUPPLY_TYPE_MAINS,
79 .supplied_to = pda_power_supplied_to,
80 .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
81 .properties = pda_power_props,
82 .num_properties = ARRAY_SIZE(pda_power_props),
83 .get_property = pda_power_get_property,
84 };
85
86 static struct power_supply pda_psy_usb = {
87 .name = "usb",
88 .type = POWER_SUPPLY_TYPE_USB,
89 .supplied_to = pda_power_supplied_to,
90 .num_supplicants = ARRAY_SIZE(pda_power_supplied_to),
91 .properties = pda_power_props,
92 .num_properties = ARRAY_SIZE(pda_power_props),
93 .get_property = pda_power_get_property,
94 };
95
update_status(void)96 static void update_status(void)
97 {
98 if (pdata->is_ac_online)
99 new_ac_status = !!pdata->is_ac_online();
100
101 if (pdata->is_usb_online)
102 new_usb_status = !!pdata->is_usb_online();
103 }
104
update_charger(void)105 static void update_charger(void)
106 {
107 if (!pdata->set_charge)
108 return;
109
110 if (new_ac_status > 0) {
111 dev_dbg(dev, "charger on (AC)\n");
112 pdata->set_charge(PDA_POWER_CHARGE_AC);
113 } else if (new_usb_status > 0) {
114 dev_dbg(dev, "charger on (USB)\n");
115 pdata->set_charge(PDA_POWER_CHARGE_USB);
116 } else {
117 dev_dbg(dev, "charger off\n");
118 pdata->set_charge(0);
119 }
120 }
121
supply_timer_func(unsigned long unused)122 static void supply_timer_func(unsigned long unused)
123 {
124 if (ac_status == PDA_PSY_TO_CHANGE) {
125 ac_status = new_ac_status;
126 power_supply_changed(&pda_psy_ac);
127 }
128
129 if (usb_status == PDA_PSY_TO_CHANGE) {
130 usb_status = new_usb_status;
131 power_supply_changed(&pda_psy_usb);
132 }
133 }
134
psy_changed(void)135 static void psy_changed(void)
136 {
137 update_charger();
138
139 /*
140 * Okay, charger set. Now wait a bit before notifying supplicants,
141 * charge power should stabilize.
142 */
143 mod_timer(&supply_timer,
144 jiffies + msecs_to_jiffies(pdata->wait_for_charger));
145 }
146
charger_timer_func(unsigned long unused)147 static void charger_timer_func(unsigned long unused)
148 {
149 update_status();
150 psy_changed();
151 }
152
power_changed_isr(int irq,void * power_supply)153 static irqreturn_t power_changed_isr(int irq, void *power_supply)
154 {
155 if (power_supply == &pda_psy_ac)
156 ac_status = PDA_PSY_TO_CHANGE;
157 else if (power_supply == &pda_psy_usb)
158 usb_status = PDA_PSY_TO_CHANGE;
159 else
160 return IRQ_NONE;
161
162 /*
163 * Wait a bit before reading ac/usb line status and setting charger,
164 * because ac/usb status readings may lag from irq.
165 */
166 mod_timer(&charger_timer,
167 jiffies + msecs_to_jiffies(pdata->wait_for_status));
168
169 return IRQ_HANDLED;
170 }
171
polling_timer_func(unsigned long unused)172 static void polling_timer_func(unsigned long unused)
173 {
174 int changed = 0;
175
176 dev_dbg(dev, "polling...\n");
177
178 update_status();
179
180 if (!ac_irq && new_ac_status != ac_status) {
181 ac_status = PDA_PSY_TO_CHANGE;
182 changed = 1;
183 }
184
185 if (!usb_irq && new_usb_status != usb_status) {
186 usb_status = PDA_PSY_TO_CHANGE;
187 changed = 1;
188 }
189
190 if (changed)
191 psy_changed();
192
193 mod_timer(&polling_timer,
194 jiffies + msecs_to_jiffies(pdata->polling_interval));
195 }
196
pda_power_probe(struct platform_device * pdev)197 static int pda_power_probe(struct platform_device *pdev)
198 {
199 int ret = 0;
200
201 dev = &pdev->dev;
202
203 if (pdev->id != -1) {
204 dev_err(dev, "it's meaningless to register several "
205 "pda_powers; use id = -1\n");
206 ret = -EINVAL;
207 goto wrongid;
208 }
209
210 pdata = pdev->dev.platform_data;
211
212 if (pdata->init) {
213 ret = pdata->init(dev);
214 if (ret < 0)
215 goto init_failed;
216 }
217
218 update_status();
219 update_charger();
220
221 if (!pdata->wait_for_status)
222 pdata->wait_for_status = 500;
223
224 if (!pdata->wait_for_charger)
225 pdata->wait_for_charger = 500;
226
227 if (!pdata->polling_interval)
228 pdata->polling_interval = 2000;
229
230 setup_timer(&charger_timer, charger_timer_func, 0);
231 setup_timer(&supply_timer, supply_timer_func, 0);
232
233 ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
234 usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
235
236 if (pdata->supplied_to) {
237 pda_psy_ac.supplied_to = pdata->supplied_to;
238 pda_psy_ac.num_supplicants = pdata->num_supplicants;
239 pda_psy_usb.supplied_to = pdata->supplied_to;
240 pda_psy_usb.num_supplicants = pdata->num_supplicants;
241 }
242
243 if (pdata->is_ac_online) {
244 ret = power_supply_register(&pdev->dev, &pda_psy_ac);
245 if (ret) {
246 dev_err(dev, "failed to register %s power supply\n",
247 pda_psy_ac.name);
248 goto ac_supply_failed;
249 }
250
251 if (ac_irq) {
252 ret = request_irq(ac_irq->start, power_changed_isr,
253 get_irq_flags(ac_irq), ac_irq->name,
254 &pda_psy_ac);
255 if (ret) {
256 dev_err(dev, "request ac irq failed\n");
257 goto ac_irq_failed;
258 }
259 } else {
260 polling = 1;
261 }
262 }
263
264 if (pdata->is_usb_online) {
265 ret = power_supply_register(&pdev->dev, &pda_psy_usb);
266 if (ret) {
267 dev_err(dev, "failed to register %s power supply\n",
268 pda_psy_usb.name);
269 goto usb_supply_failed;
270 }
271
272 if (usb_irq) {
273 ret = request_irq(usb_irq->start, power_changed_isr,
274 get_irq_flags(usb_irq),
275 usb_irq->name, &pda_psy_usb);
276 if (ret) {
277 dev_err(dev, "request usb irq failed\n");
278 goto usb_irq_failed;
279 }
280 } else {
281 polling = 1;
282 }
283 }
284
285 if (polling) {
286 dev_dbg(dev, "will poll for status\n");
287 setup_timer(&polling_timer, polling_timer_func, 0);
288 mod_timer(&polling_timer,
289 jiffies + msecs_to_jiffies(pdata->polling_interval));
290 }
291
292 if (ac_irq || usb_irq)
293 device_init_wakeup(&pdev->dev, 1);
294
295 return 0;
296
297 usb_irq_failed:
298 if (pdata->is_usb_online)
299 power_supply_unregister(&pda_psy_usb);
300 usb_supply_failed:
301 if (pdata->is_ac_online && ac_irq)
302 free_irq(ac_irq->start, &pda_psy_ac);
303 ac_irq_failed:
304 if (pdata->is_ac_online)
305 power_supply_unregister(&pda_psy_ac);
306 ac_supply_failed:
307 if (pdata->exit)
308 pdata->exit(dev);
309 init_failed:
310 wrongid:
311 return ret;
312 }
313
pda_power_remove(struct platform_device * pdev)314 static int pda_power_remove(struct platform_device *pdev)
315 {
316 if (pdata->is_usb_online && usb_irq)
317 free_irq(usb_irq->start, &pda_psy_usb);
318 if (pdata->is_ac_online && ac_irq)
319 free_irq(ac_irq->start, &pda_psy_ac);
320
321 if (polling)
322 del_timer_sync(&polling_timer);
323 del_timer_sync(&charger_timer);
324 del_timer_sync(&supply_timer);
325
326 if (pdata->is_usb_online)
327 power_supply_unregister(&pda_psy_usb);
328 if (pdata->is_ac_online)
329 power_supply_unregister(&pda_psy_ac);
330 if (pdata->exit)
331 pdata->exit(dev);
332
333 return 0;
334 }
335
336 #ifdef CONFIG_PM
337 static int ac_wakeup_enabled;
338 static int usb_wakeup_enabled;
339
pda_power_suspend(struct platform_device * pdev,pm_message_t state)340 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
341 {
342 if (device_may_wakeup(&pdev->dev)) {
343 if (ac_irq)
344 ac_wakeup_enabled = !enable_irq_wake(ac_irq->start);
345 if (usb_irq)
346 usb_wakeup_enabled = !enable_irq_wake(usb_irq->start);
347 }
348
349 return 0;
350 }
351
pda_power_resume(struct platform_device * pdev)352 static int pda_power_resume(struct platform_device *pdev)
353 {
354 if (device_may_wakeup(&pdev->dev)) {
355 if (usb_irq && usb_wakeup_enabled)
356 disable_irq_wake(usb_irq->start);
357 if (ac_irq && ac_wakeup_enabled)
358 disable_irq_wake(ac_irq->start);
359 }
360
361 return 0;
362 }
363 #else
364 #define pda_power_suspend NULL
365 #define pda_power_resume NULL
366 #endif /* CONFIG_PM */
367
368 MODULE_ALIAS("platform:pda-power");
369
370 static struct platform_driver pda_power_pdrv = {
371 .driver = {
372 .name = "pda-power",
373 },
374 .probe = pda_power_probe,
375 .remove = pda_power_remove,
376 .suspend = pda_power_suspend,
377 .resume = pda_power_resume,
378 };
379
pda_power_init(void)380 static int __init pda_power_init(void)
381 {
382 return platform_driver_register(&pda_power_pdrv);
383 }
384
pda_power_exit(void)385 static void __exit pda_power_exit(void)
386 {
387 platform_driver_unregister(&pda_power_pdrv);
388 }
389
390 module_init(pda_power_init);
391 module_exit(pda_power_exit);
392 MODULE_LICENSE("GPL");
393 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");
394