parport: remove superfluous local variable
[linux-2.6] / drivers / power / pda_power.c
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
21 static inline unsigned int get_irq_flags(struct resource *res)
22 {
23         unsigned int flags = IRQF_DISABLED | 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
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
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
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
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
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
147 static void charger_timer_func(unsigned long unused)
148 {
149         update_status();
150         psy_changed();
151 }
152
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
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
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
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 pda_power_suspend(struct platform_device *pdev, pm_message_t state)
338 {
339         if (device_may_wakeup(&pdev->dev)) {
340                 if (ac_irq)
341                         enable_irq_wake(ac_irq->start);
342                 if (usb_irq)
343                         enable_irq_wake(usb_irq->start);
344         }
345
346         return 0;
347 }
348
349 static int pda_power_resume(struct platform_device *pdev)
350 {
351         if (device_may_wakeup(&pdev->dev)) {
352                 if (usb_irq)
353                         disable_irq_wake(usb_irq->start);
354                 if (ac_irq)
355                         disable_irq_wake(ac_irq->start);
356         }
357
358         return 0;
359 }
360 #else
361 #define pda_power_suspend NULL
362 #define pda_power_resume NULL
363 #endif /* CONFIG_PM */
364
365 MODULE_ALIAS("platform:pda-power");
366
367 static struct platform_driver pda_power_pdrv = {
368         .driver = {
369                 .name = "pda-power",
370         },
371         .probe = pda_power_probe,
372         .remove = pda_power_remove,
373         .suspend = pda_power_suspend,
374         .resume = pda_power_resume,
375 };
376
377 static int __init pda_power_init(void)
378 {
379         return platform_driver_register(&pda_power_pdrv);
380 }
381
382 static void __exit pda_power_exit(void)
383 {
384         platform_driver_unregister(&pda_power_pdrv);
385 }
386
387 module_init(pda_power_init);
388 module_exit(pda_power_exit);
389 MODULE_LICENSE("GPL");
390 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");