1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Common power driver for PDAs and phones with one or two external
4 * power supplies (AC/USB) connected to main and backup batteries,
5 * and optional builtin charger.
6 *
7 * Copyright © 2007 Anton Vorontsov <cbou@mail.ru>
8 */
9
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/err.h>
13 #include <linux/interrupt.h>
14 #include <linux/notifier.h>
15 #include <linux/power_supply.h>
16 #include <linux/pda_power.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/timer.h>
19 #include <linux/jiffies.h>
20 #include <linux/usb/otg.h>
21
get_irq_flags(struct resource * res)22 static inline unsigned int get_irq_flags(struct resource *res)
23 {
24 return IRQF_SHARED | (res->flags & IRQF_TRIGGER_MASK);
25 }
26
27 static struct device *dev;
28 static struct pda_power_pdata *pdata;
29 static struct resource *ac_irq, *usb_irq;
30 static struct delayed_work charger_work;
31 static struct delayed_work polling_work;
32 static struct delayed_work supply_work;
33 static int polling;
34 static struct power_supply *pda_psy_ac, *pda_psy_usb;
35
36 #if IS_ENABLED(CONFIG_USB_PHY)
37 static struct usb_phy *transceiver;
38 static struct notifier_block otg_nb;
39 #endif
40
41 static struct regulator *ac_draw;
42
43 enum {
44 PDA_PSY_OFFLINE = 0,
45 PDA_PSY_ONLINE = 1,
46 PDA_PSY_TO_CHANGE,
47 };
48 static int new_ac_status = -1;
49 static int new_usb_status = -1;
50 static int ac_status = -1;
51 static int usb_status = -1;
52
pda_power_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)53 static int pda_power_get_property(struct power_supply *psy,
54 enum power_supply_property psp,
55 union power_supply_propval *val)
56 {
57 switch (psp) {
58 case POWER_SUPPLY_PROP_ONLINE:
59 if (psy->desc->type == POWER_SUPPLY_TYPE_MAINS)
60 val->intval = pdata->is_ac_online ?
61 pdata->is_ac_online() : 0;
62 else
63 val->intval = pdata->is_usb_online ?
64 pdata->is_usb_online() : 0;
65 break;
66 default:
67 return -EINVAL;
68 }
69 return 0;
70 }
71
72 static enum power_supply_property pda_power_props[] = {
73 POWER_SUPPLY_PROP_ONLINE,
74 };
75
76 static char *pda_power_supplied_to[] = {
77 "main-battery",
78 "backup-battery",
79 };
80
81 static const struct power_supply_desc pda_psy_ac_desc = {
82 .name = "ac",
83 .type = POWER_SUPPLY_TYPE_MAINS,
84 .properties = pda_power_props,
85 .num_properties = ARRAY_SIZE(pda_power_props),
86 .get_property = pda_power_get_property,
87 };
88
89 static const struct power_supply_desc pda_psy_usb_desc = {
90 .name = "usb",
91 .type = POWER_SUPPLY_TYPE_USB,
92 .properties = pda_power_props,
93 .num_properties = ARRAY_SIZE(pda_power_props),
94 .get_property = pda_power_get_property,
95 };
96
update_status(void)97 static void update_status(void)
98 {
99 if (pdata->is_ac_online)
100 new_ac_status = !!pdata->is_ac_online();
101
102 if (pdata->is_usb_online)
103 new_usb_status = !!pdata->is_usb_online();
104 }
105
update_charger(void)106 static void update_charger(void)
107 {
108 static int regulator_enabled;
109 int max_uA = pdata->ac_max_uA;
110
111 if (pdata->set_charge) {
112 if (new_ac_status > 0) {
113 dev_dbg(dev, "charger on (AC)\n");
114 pdata->set_charge(PDA_POWER_CHARGE_AC);
115 } else if (new_usb_status > 0) {
116 dev_dbg(dev, "charger on (USB)\n");
117 pdata->set_charge(PDA_POWER_CHARGE_USB);
118 } else {
119 dev_dbg(dev, "charger off\n");
120 pdata->set_charge(0);
121 }
122 } else if (ac_draw) {
123 if (new_ac_status > 0) {
124 regulator_set_current_limit(ac_draw, max_uA, max_uA);
125 if (!regulator_enabled) {
126 dev_dbg(dev, "charger on (AC)\n");
127 WARN_ON(regulator_enable(ac_draw));
128 regulator_enabled = 1;
129 }
130 } else {
131 if (regulator_enabled) {
132 dev_dbg(dev, "charger off\n");
133 WARN_ON(regulator_disable(ac_draw));
134 regulator_enabled = 0;
135 }
136 }
137 }
138 }
139
supply_work_func(struct work_struct * work)140 static void supply_work_func(struct work_struct *work)
141 {
142 if (ac_status == PDA_PSY_TO_CHANGE) {
143 ac_status = new_ac_status;
144 power_supply_changed(pda_psy_ac);
145 }
146
147 if (usb_status == PDA_PSY_TO_CHANGE) {
148 usb_status = new_usb_status;
149 power_supply_changed(pda_psy_usb);
150 }
151 }
152
psy_changed(void)153 static void psy_changed(void)
154 {
155 update_charger();
156
157 /*
158 * Okay, charger set. Now wait a bit before notifying supplicants,
159 * charge power should stabilize.
160 */
161 cancel_delayed_work(&supply_work);
162 schedule_delayed_work(&supply_work,
163 msecs_to_jiffies(pdata->wait_for_charger));
164 }
165
charger_work_func(struct work_struct * work)166 static void charger_work_func(struct work_struct *work)
167 {
168 update_status();
169 psy_changed();
170 }
171
power_changed_isr(int irq,void * power_supply)172 static irqreturn_t power_changed_isr(int irq, void *power_supply)
173 {
174 if (power_supply == pda_psy_ac)
175 ac_status = PDA_PSY_TO_CHANGE;
176 else if (power_supply == pda_psy_usb)
177 usb_status = PDA_PSY_TO_CHANGE;
178 else
179 return IRQ_NONE;
180
181 /*
182 * Wait a bit before reading ac/usb line status and setting charger,
183 * because ac/usb status readings may lag from irq.
184 */
185 cancel_delayed_work(&charger_work);
186 schedule_delayed_work(&charger_work,
187 msecs_to_jiffies(pdata->wait_for_status));
188
189 return IRQ_HANDLED;
190 }
191
polling_work_func(struct work_struct * work)192 static void polling_work_func(struct work_struct *work)
193 {
194 int changed = 0;
195
196 dev_dbg(dev, "polling...\n");
197
198 update_status();
199
200 if (!ac_irq && new_ac_status != ac_status) {
201 ac_status = PDA_PSY_TO_CHANGE;
202 changed = 1;
203 }
204
205 if (!usb_irq && new_usb_status != usb_status) {
206 usb_status = PDA_PSY_TO_CHANGE;
207 changed = 1;
208 }
209
210 if (changed)
211 psy_changed();
212
213 cancel_delayed_work(&polling_work);
214 schedule_delayed_work(&polling_work,
215 msecs_to_jiffies(pdata->polling_interval));
216 }
217
218 #if IS_ENABLED(CONFIG_USB_PHY)
otg_is_usb_online(void)219 static int otg_is_usb_online(void)
220 {
221 return (transceiver->last_event == USB_EVENT_VBUS ||
222 transceiver->last_event == USB_EVENT_ENUMERATED);
223 }
224
otg_is_ac_online(void)225 static int otg_is_ac_online(void)
226 {
227 return (transceiver->last_event == USB_EVENT_CHARGER);
228 }
229
otg_handle_notification(struct notifier_block * nb,unsigned long event,void * unused)230 static int otg_handle_notification(struct notifier_block *nb,
231 unsigned long event, void *unused)
232 {
233 switch (event) {
234 case USB_EVENT_CHARGER:
235 ac_status = PDA_PSY_TO_CHANGE;
236 break;
237 case USB_EVENT_VBUS:
238 case USB_EVENT_ENUMERATED:
239 usb_status = PDA_PSY_TO_CHANGE;
240 break;
241 case USB_EVENT_NONE:
242 ac_status = PDA_PSY_TO_CHANGE;
243 usb_status = PDA_PSY_TO_CHANGE;
244 break;
245 default:
246 return NOTIFY_OK;
247 }
248
249 /*
250 * Wait a bit before reading ac/usb line status and setting charger,
251 * because ac/usb status readings may lag from irq.
252 */
253 cancel_delayed_work(&charger_work);
254 schedule_delayed_work(&charger_work,
255 msecs_to_jiffies(pdata->wait_for_status));
256
257 return NOTIFY_OK;
258 }
259 #endif
260
pda_power_probe(struct platform_device * pdev)261 static int pda_power_probe(struct platform_device *pdev)
262 {
263 struct power_supply_config psy_cfg = {};
264 int ret = 0;
265
266 dev = &pdev->dev;
267
268 if (pdev->id != -1) {
269 dev_err(dev, "it's meaningless to register several "
270 "pda_powers; use id = -1\n");
271 ret = -EINVAL;
272 goto wrongid;
273 }
274
275 pdata = pdev->dev.platform_data;
276
277 if (pdata->init) {
278 ret = pdata->init(dev);
279 if (ret < 0)
280 goto init_failed;
281 }
282
283 ac_draw = regulator_get(dev, "ac_draw");
284 if (IS_ERR(ac_draw)) {
285 dev_dbg(dev, "couldn't get ac_draw regulator\n");
286 ac_draw = NULL;
287 }
288
289 update_status();
290 update_charger();
291
292 if (!pdata->wait_for_status)
293 pdata->wait_for_status = 500;
294
295 if (!pdata->wait_for_charger)
296 pdata->wait_for_charger = 500;
297
298 if (!pdata->polling_interval)
299 pdata->polling_interval = 2000;
300
301 if (!pdata->ac_max_uA)
302 pdata->ac_max_uA = 500000;
303
304 INIT_DELAYED_WORK(&charger_work, charger_work_func);
305 INIT_DELAYED_WORK(&supply_work, supply_work_func);
306
307 ac_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ac");
308 usb_irq = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "usb");
309
310 if (pdata->supplied_to) {
311 psy_cfg.supplied_to = pdata->supplied_to;
312 psy_cfg.num_supplicants = pdata->num_supplicants;
313 } else {
314 psy_cfg.supplied_to = pda_power_supplied_to;
315 psy_cfg.num_supplicants = ARRAY_SIZE(pda_power_supplied_to);
316 }
317
318 #if IS_ENABLED(CONFIG_USB_PHY)
319 transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
320 if (!IS_ERR_OR_NULL(transceiver)) {
321 if (!pdata->is_usb_online)
322 pdata->is_usb_online = otg_is_usb_online;
323 if (!pdata->is_ac_online)
324 pdata->is_ac_online = otg_is_ac_online;
325 }
326 #endif
327
328 if (pdata->is_ac_online) {
329 pda_psy_ac = power_supply_register(&pdev->dev,
330 &pda_psy_ac_desc, &psy_cfg);
331 if (IS_ERR(pda_psy_ac)) {
332 dev_err(dev, "failed to register %s power supply\n",
333 pda_psy_ac_desc.name);
334 ret = PTR_ERR(pda_psy_ac);
335 goto ac_supply_failed;
336 }
337
338 if (ac_irq) {
339 ret = request_irq(ac_irq->start, power_changed_isr,
340 get_irq_flags(ac_irq), ac_irq->name,
341 pda_psy_ac);
342 if (ret) {
343 dev_err(dev, "request ac irq failed\n");
344 goto ac_irq_failed;
345 }
346 } else {
347 polling = 1;
348 }
349 }
350
351 if (pdata->is_usb_online) {
352 pda_psy_usb = power_supply_register(&pdev->dev,
353 &pda_psy_usb_desc,
354 &psy_cfg);
355 if (IS_ERR(pda_psy_usb)) {
356 dev_err(dev, "failed to register %s power supply\n",
357 pda_psy_usb_desc.name);
358 ret = PTR_ERR(pda_psy_usb);
359 goto usb_supply_failed;
360 }
361
362 if (usb_irq) {
363 ret = request_irq(usb_irq->start, power_changed_isr,
364 get_irq_flags(usb_irq),
365 usb_irq->name, pda_psy_usb);
366 if (ret) {
367 dev_err(dev, "request usb irq failed\n");
368 goto usb_irq_failed;
369 }
370 } else {
371 polling = 1;
372 }
373 }
374
375 #if IS_ENABLED(CONFIG_USB_PHY)
376 if (!IS_ERR_OR_NULL(transceiver) && pdata->use_otg_notifier) {
377 otg_nb.notifier_call = otg_handle_notification;
378 ret = usb_register_notifier(transceiver, &otg_nb);
379 if (ret) {
380 dev_err(dev, "failure to register otg notifier\n");
381 goto otg_reg_notifier_failed;
382 }
383 polling = 0;
384 }
385 #endif
386
387 if (polling) {
388 dev_dbg(dev, "will poll for status\n");
389 INIT_DELAYED_WORK(&polling_work, polling_work_func);
390 cancel_delayed_work(&polling_work);
391 schedule_delayed_work(&polling_work,
392 msecs_to_jiffies(pdata->polling_interval));
393 }
394
395 if (ac_irq || usb_irq)
396 device_init_wakeup(&pdev->dev, 1);
397
398 return 0;
399
400 #if IS_ENABLED(CONFIG_USB_PHY)
401 otg_reg_notifier_failed:
402 if (pdata->is_usb_online && usb_irq)
403 free_irq(usb_irq->start, pda_psy_usb);
404 #endif
405 usb_irq_failed:
406 if (pdata->is_usb_online)
407 power_supply_unregister(pda_psy_usb);
408 usb_supply_failed:
409 if (pdata->is_ac_online && ac_irq)
410 free_irq(ac_irq->start, pda_psy_ac);
411 #if IS_ENABLED(CONFIG_USB_PHY)
412 if (!IS_ERR_OR_NULL(transceiver))
413 usb_put_phy(transceiver);
414 #endif
415 ac_irq_failed:
416 if (pdata->is_ac_online)
417 power_supply_unregister(pda_psy_ac);
418 ac_supply_failed:
419 if (ac_draw) {
420 regulator_put(ac_draw);
421 ac_draw = NULL;
422 }
423 if (pdata->exit)
424 pdata->exit(dev);
425 init_failed:
426 wrongid:
427 return ret;
428 }
429
pda_power_remove(struct platform_device * pdev)430 static int pda_power_remove(struct platform_device *pdev)
431 {
432 #if IS_ENABLED(CONFIG_USB_PHY)
433 if (!IS_ERR_OR_NULL(transceiver) && pdata->use_otg_notifier)
434 usb_unregister_notifier(transceiver, &otg_nb);
435 #endif
436 if (pdata->is_usb_online && usb_irq)
437 free_irq(usb_irq->start, pda_psy_usb);
438 if (pdata->is_ac_online && ac_irq)
439 free_irq(ac_irq->start, pda_psy_ac);
440
441 if (polling)
442 cancel_delayed_work_sync(&polling_work);
443 cancel_delayed_work_sync(&charger_work);
444 cancel_delayed_work_sync(&supply_work);
445
446 if (pdata->is_usb_online)
447 power_supply_unregister(pda_psy_usb);
448 if (pdata->is_ac_online)
449 power_supply_unregister(pda_psy_ac);
450 #if IS_ENABLED(CONFIG_USB_PHY)
451 if (!IS_ERR_OR_NULL(transceiver))
452 usb_put_phy(transceiver);
453 #endif
454 if (ac_draw) {
455 regulator_put(ac_draw);
456 ac_draw = NULL;
457 }
458 if (pdata->exit)
459 pdata->exit(dev);
460
461 return 0;
462 }
463
464 #ifdef CONFIG_PM
465 static int ac_wakeup_enabled;
466 static int usb_wakeup_enabled;
467
pda_power_suspend(struct platform_device * pdev,pm_message_t state)468 static int pda_power_suspend(struct platform_device *pdev, pm_message_t state)
469 {
470 if (pdata->suspend) {
471 int ret = pdata->suspend(state);
472
473 if (ret)
474 return ret;
475 }
476
477 if (device_may_wakeup(&pdev->dev)) {
478 if (ac_irq)
479 ac_wakeup_enabled = !enable_irq_wake(ac_irq->start);
480 if (usb_irq)
481 usb_wakeup_enabled = !enable_irq_wake(usb_irq->start);
482 }
483
484 return 0;
485 }
486
pda_power_resume(struct platform_device * pdev)487 static int pda_power_resume(struct platform_device *pdev)
488 {
489 if (device_may_wakeup(&pdev->dev)) {
490 if (usb_irq && usb_wakeup_enabled)
491 disable_irq_wake(usb_irq->start);
492 if (ac_irq && ac_wakeup_enabled)
493 disable_irq_wake(ac_irq->start);
494 }
495
496 if (pdata->resume)
497 return pdata->resume();
498
499 return 0;
500 }
501 #else
502 #define pda_power_suspend NULL
503 #define pda_power_resume NULL
504 #endif /* CONFIG_PM */
505
506 static struct platform_driver pda_power_pdrv = {
507 .driver = {
508 .name = "pda-power",
509 },
510 .probe = pda_power_probe,
511 .remove = pda_power_remove,
512 .suspend = pda_power_suspend,
513 .resume = pda_power_resume,
514 };
515
516 module_platform_driver(pda_power_pdrv);
517
518 MODULE_LICENSE("GPL");
519 MODULE_AUTHOR("Anton Vorontsov <cbou@mail.ru>");
520 MODULE_ALIAS("platform:pda-power");
521