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authorPaul Mundt <lethal@linux-sh.org>2011-01-13 01:06:28 -0500
committerPaul Mundt <lethal@linux-sh.org>2011-01-13 01:06:28 -0500
commitf43dc23d5ea91fca257be02138a255f02d98e806 (patch)
treeb29722f6e965316e90ac97abf79923ced250dc21 /drivers/rtc/interface.c
parentf8e53553f452dcbf67cb89c8cba63a1cd6eb4cc0 (diff)
parent4162cf64973df51fc885825bc9ca4d055891c49f (diff)
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 into common/serial-rework
Conflicts: arch/sh/kernel/cpu/sh2/setup-sh7619.c arch/sh/kernel/cpu/sh2a/setup-mxg.c arch/sh/kernel/cpu/sh2a/setup-sh7201.c arch/sh/kernel/cpu/sh2a/setup-sh7203.c arch/sh/kernel/cpu/sh2a/setup-sh7206.c arch/sh/kernel/cpu/sh3/setup-sh7705.c arch/sh/kernel/cpu/sh3/setup-sh770x.c arch/sh/kernel/cpu/sh3/setup-sh7710.c arch/sh/kernel/cpu/sh3/setup-sh7720.c arch/sh/kernel/cpu/sh4/setup-sh4-202.c arch/sh/kernel/cpu/sh4/setup-sh7750.c arch/sh/kernel/cpu/sh4/setup-sh7760.c arch/sh/kernel/cpu/sh4a/setup-sh7343.c arch/sh/kernel/cpu/sh4a/setup-sh7366.c arch/sh/kernel/cpu/sh4a/setup-sh7722.c arch/sh/kernel/cpu/sh4a/setup-sh7723.c arch/sh/kernel/cpu/sh4a/setup-sh7724.c arch/sh/kernel/cpu/sh4a/setup-sh7763.c arch/sh/kernel/cpu/sh4a/setup-sh7770.c arch/sh/kernel/cpu/sh4a/setup-sh7780.c arch/sh/kernel/cpu/sh4a/setup-sh7785.c arch/sh/kernel/cpu/sh4a/setup-sh7786.c arch/sh/kernel/cpu/sh4a/setup-shx3.c arch/sh/kernel/cpu/sh5/setup-sh5.c drivers/serial/sh-sci.c drivers/serial/sh-sci.h include/linux/serial_sci.h
Diffstat (limited to 'drivers/rtc/interface.c')
-rw-r--r--drivers/rtc/interface.c575
1 files changed, 350 insertions, 225 deletions
diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index 4cdb31a362ca..90384b9f6b2c 100644
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -12,16 +12,13 @@
12*/ 12*/
13 13
14#include <linux/rtc.h> 14#include <linux/rtc.h>
15#include <linux/sched.h>
15#include <linux/log2.h> 16#include <linux/log2.h>
17#include <linux/workqueue.h>
16 18
17int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm) 19static int __rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
18{ 20{
19 int err; 21 int err;
20
21 err = mutex_lock_interruptible(&rtc->ops_lock);
22 if (err)
23 return err;
24
25 if (!rtc->ops) 22 if (!rtc->ops)
26 err = -ENODEV; 23 err = -ENODEV;
27 else if (!rtc->ops->read_time) 24 else if (!rtc->ops->read_time)
@@ -30,7 +27,18 @@ int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
30 memset(tm, 0, sizeof(struct rtc_time)); 27 memset(tm, 0, sizeof(struct rtc_time));
31 err = rtc->ops->read_time(rtc->dev.parent, tm); 28 err = rtc->ops->read_time(rtc->dev.parent, tm);
32 } 29 }
30 return err;
31}
32
33int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
34{
35 int err;
33 36
37 err = mutex_lock_interruptible(&rtc->ops_lock);
38 if (err)
39 return err;
40
41 err = __rtc_read_time(rtc, tm);
34 mutex_unlock(&rtc->ops_lock); 42 mutex_unlock(&rtc->ops_lock);
35 return err; 43 return err;
36} 44}
@@ -105,188 +113,54 @@ int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs)
105} 113}
106EXPORT_SYMBOL_GPL(rtc_set_mmss); 114EXPORT_SYMBOL_GPL(rtc_set_mmss);
107 115
108static int rtc_read_alarm_internal(struct rtc_device *rtc, struct rtc_wkalrm *alarm) 116int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
109{ 117{
110 int err; 118 int err;
111 119
112 err = mutex_lock_interruptible(&rtc->ops_lock); 120 err = mutex_lock_interruptible(&rtc->ops_lock);
113 if (err) 121 if (err)
114 return err; 122 return err;
115 123 alarm->enabled = rtc->aie_timer.enabled;
116 if (rtc->ops == NULL) 124 if (alarm->enabled)
117 err = -ENODEV; 125 alarm->time = rtc_ktime_to_tm(rtc->aie_timer.node.expires);
118 else if (!rtc->ops->read_alarm)
119 err = -EINVAL;
120 else {
121 memset(alarm, 0, sizeof(struct rtc_wkalrm));
122 err = rtc->ops->read_alarm(rtc->dev.parent, alarm);
123 }
124
125 mutex_unlock(&rtc->ops_lock); 126 mutex_unlock(&rtc->ops_lock);
126 return err; 127
128 return 0;
127} 129}
130EXPORT_SYMBOL_GPL(rtc_read_alarm);
128 131
129int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) 132int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
130{ 133{
134 struct rtc_time tm;
135 long now, scheduled;
131 int err; 136 int err;
132 struct rtc_time before, now;
133 int first_time = 1;
134 unsigned long t_now, t_alm;
135 enum { none, day, month, year } missing = none;
136 unsigned days;
137
138 /* The lower level RTC driver may return -1 in some fields,
139 * creating invalid alarm->time values, for reasons like:
140 *
141 * - The hardware may not be capable of filling them in;
142 * many alarms match only on time-of-day fields, not
143 * day/month/year calendar data.
144 *
145 * - Some hardware uses illegal values as "wildcard" match
146 * values, which non-Linux firmware (like a BIOS) may try
147 * to set up as e.g. "alarm 15 minutes after each hour".
148 * Linux uses only oneshot alarms.
149 *
150 * When we see that here, we deal with it by using values from
151 * a current RTC timestamp for any missing (-1) values. The
152 * RTC driver prevents "periodic alarm" modes.
153 *
154 * But this can be racey, because some fields of the RTC timestamp
155 * may have wrapped in the interval since we read the RTC alarm,
156 * which would lead to us inserting inconsistent values in place
157 * of the -1 fields.
158 *
159 * Reading the alarm and timestamp in the reverse sequence
160 * would have the same race condition, and not solve the issue.
161 *
162 * So, we must first read the RTC timestamp,
163 * then read the RTC alarm value,
164 * and then read a second RTC timestamp.
165 *
166 * If any fields of the second timestamp have changed
167 * when compared with the first timestamp, then we know
168 * our timestamp may be inconsistent with that used by
169 * the low-level rtc_read_alarm_internal() function.
170 *
171 * So, when the two timestamps disagree, we just loop and do
172 * the process again to get a fully consistent set of values.
173 *
174 * This could all instead be done in the lower level driver,
175 * but since more than one lower level RTC implementation needs it,
176 * then it's probably best best to do it here instead of there..
177 */
178 137
179 /* Get the "before" timestamp */ 138 err = rtc_valid_tm(&alarm->time);
180 err = rtc_read_time(rtc, &before); 139 if (err)
181 if (err < 0)
182 return err; 140 return err;
183 do { 141 rtc_tm_to_time(&alarm->time, &scheduled);
184 if (!first_time)
185 memcpy(&before, &now, sizeof(struct rtc_time));
186 first_time = 0;
187
188 /* get the RTC alarm values, which may be incomplete */
189 err = rtc_read_alarm_internal(rtc, alarm);
190 if (err)
191 return err;
192 if (!alarm->enabled)
193 return 0;
194
195 /* full-function RTCs won't have such missing fields */
196 if (rtc_valid_tm(&alarm->time) == 0)
197 return 0;
198
199 /* get the "after" timestamp, to detect wrapped fields */
200 err = rtc_read_time(rtc, &now);
201 if (err < 0)
202 return err;
203
204 /* note that tm_sec is a "don't care" value here: */
205 } while ( before.tm_min != now.tm_min
206 || before.tm_hour != now.tm_hour
207 || before.tm_mon != now.tm_mon
208 || before.tm_year != now.tm_year);
209
210 /* Fill in the missing alarm fields using the timestamp; we
211 * know there's at least one since alarm->time is invalid.
212 */
213 if (alarm->time.tm_sec == -1)
214 alarm->time.tm_sec = now.tm_sec;
215 if (alarm->time.tm_min == -1)
216 alarm->time.tm_min = now.tm_min;
217 if (alarm->time.tm_hour == -1)
218 alarm->time.tm_hour = now.tm_hour;
219
220 /* For simplicity, only support date rollover for now */
221 if (alarm->time.tm_mday == -1) {
222 alarm->time.tm_mday = now.tm_mday;
223 missing = day;
224 }
225 if (alarm->time.tm_mon == -1) {
226 alarm->time.tm_mon = now.tm_mon;
227 if (missing == none)
228 missing = month;
229 }
230 if (alarm->time.tm_year == -1) {
231 alarm->time.tm_year = now.tm_year;
232 if (missing == none)
233 missing = year;
234 }
235
236 /* with luck, no rollover is needed */
237 rtc_tm_to_time(&now, &t_now);
238 rtc_tm_to_time(&alarm->time, &t_alm);
239 if (t_now < t_alm)
240 goto done;
241
242 switch (missing) {
243 142
244 /* 24 hour rollover ... if it's now 10am Monday, an alarm that 143 /* Make sure we're not setting alarms in the past */
245 * that will trigger at 5am will do so at 5am Tuesday, which 144 err = __rtc_read_time(rtc, &tm);
246 * could also be in the next month or year. This is a common 145 rtc_tm_to_time(&tm, &now);
247 * case, especially for PCs. 146 if (scheduled <= now)
248 */ 147 return -ETIME;
249 case day: 148 /*
250 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "day"); 149 * XXX - We just checked to make sure the alarm time is not
251 t_alm += 24 * 60 * 60; 150 * in the past, but there is still a race window where if
252 rtc_time_to_tm(t_alm, &alarm->time); 151 * the is alarm set for the next second and the second ticks
253 break; 152 * over right here, before we set the alarm.
254
255 /* Month rollover ... if it's the 31th, an alarm on the 3rd will
256 * be next month. An alarm matching on the 30th, 29th, or 28th
257 * may end up in the month after that! Many newer PCs support
258 * this type of alarm.
259 */ 153 */
260 case month:
261 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "month");
262 do {
263 if (alarm->time.tm_mon < 11)
264 alarm->time.tm_mon++;
265 else {
266 alarm->time.tm_mon = 0;
267 alarm->time.tm_year++;
268 }
269 days = rtc_month_days(alarm->time.tm_mon,
270 alarm->time.tm_year);
271 } while (days < alarm->time.tm_mday);
272 break;
273
274 /* Year rollover ... easy except for leap years! */
275 case year:
276 dev_dbg(&rtc->dev, "alarm rollover: %s\n", "year");
277 do {
278 alarm->time.tm_year++;
279 } while (rtc_valid_tm(&alarm->time) != 0);
280 break;
281
282 default:
283 dev_warn(&rtc->dev, "alarm rollover not handled\n");
284 }
285 154
286done: 155 if (!rtc->ops)
287 return 0; 156 err = -ENODEV;
157 else if (!rtc->ops->set_alarm)
158 err = -EINVAL;
159 else
160 err = rtc->ops->set_alarm(rtc->dev.parent, alarm);
161
162 return err;
288} 163}
289EXPORT_SYMBOL_GPL(rtc_read_alarm);
290 164
291int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) 165int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
292{ 166{
@@ -299,16 +173,18 @@ int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
299 err = mutex_lock_interruptible(&rtc->ops_lock); 173 err = mutex_lock_interruptible(&rtc->ops_lock);
300 if (err) 174 if (err)
301 return err; 175 return err;
302 176 if (rtc->aie_timer.enabled) {
303 if (!rtc->ops) 177 rtc_timer_remove(rtc, &rtc->aie_timer);
304 err = -ENODEV; 178 rtc->aie_timer.enabled = 0;
305 else if (!rtc->ops->set_alarm) 179 }
306 err = -EINVAL; 180 rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
307 else 181 rtc->aie_timer.period = ktime_set(0, 0);
308 err = rtc->ops->set_alarm(rtc->dev.parent, alarm); 182 if (alarm->enabled) {
309 183 rtc->aie_timer.enabled = 1;
184 rtc_timer_enqueue(rtc, &rtc->aie_timer);
185 }
310 mutex_unlock(&rtc->ops_lock); 186 mutex_unlock(&rtc->ops_lock);
311 return err; 187 return 0;
312} 188}
313EXPORT_SYMBOL_GPL(rtc_set_alarm); 189EXPORT_SYMBOL_GPL(rtc_set_alarm);
314 190
@@ -318,6 +194,16 @@ int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled)
318 if (err) 194 if (err)
319 return err; 195 return err;
320 196
197 if (rtc->aie_timer.enabled != enabled) {
198 if (enabled) {
199 rtc->aie_timer.enabled = 1;
200 rtc_timer_enqueue(rtc, &rtc->aie_timer);
201 } else {
202 rtc_timer_remove(rtc, &rtc->aie_timer);
203 rtc->aie_timer.enabled = 0;
204 }
205 }
206
321 if (!rtc->ops) 207 if (!rtc->ops)
322 err = -ENODEV; 208 err = -ENODEV;
323 else if (!rtc->ops->alarm_irq_enable) 209 else if (!rtc->ops->alarm_irq_enable)
@@ -336,52 +222,53 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
336 if (err) 222 if (err)
337 return err; 223 return err;
338 224
339#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL 225 /* make sure we're changing state */
340 if (enabled == 0 && rtc->uie_irq_active) { 226 if (rtc->uie_rtctimer.enabled == enabled)
341 mutex_unlock(&rtc->ops_lock); 227 goto out;
342 return rtc_dev_update_irq_enable_emul(rtc, enabled); 228
229 if (enabled) {
230 struct rtc_time tm;
231 ktime_t now, onesec;
232
233 __rtc_read_time(rtc, &tm);
234 onesec = ktime_set(1, 0);
235 now = rtc_tm_to_ktime(tm);
236 rtc->uie_rtctimer.node.expires = ktime_add(now, onesec);
237 rtc->uie_rtctimer.period = ktime_set(1, 0);
238 rtc->uie_rtctimer.enabled = 1;
239 rtc_timer_enqueue(rtc, &rtc->uie_rtctimer);
240 } else {
241 rtc_timer_remove(rtc, &rtc->uie_rtctimer);
242 rtc->uie_rtctimer.enabled = 0;
343 } 243 }
344#endif
345
346 if (!rtc->ops)
347 err = -ENODEV;
348 else if (!rtc->ops->update_irq_enable)
349 err = -EINVAL;
350 else
351 err = rtc->ops->update_irq_enable(rtc->dev.parent, enabled);
352 244
245out:
353 mutex_unlock(&rtc->ops_lock); 246 mutex_unlock(&rtc->ops_lock);
354
355#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
356 /*
357 * Enable emulation if the driver did not provide
358 * the update_irq_enable function pointer or if returned
359 * -EINVAL to signal that it has been configured without
360 * interrupts or that are not available at the moment.
361 */
362 if (err == -EINVAL)
363 err = rtc_dev_update_irq_enable_emul(rtc, enabled);
364#endif
365 return err; 247 return err;
248
366} 249}
367EXPORT_SYMBOL_GPL(rtc_update_irq_enable); 250EXPORT_SYMBOL_GPL(rtc_update_irq_enable);
368 251
252
369/** 253/**
370 * rtc_update_irq - report RTC periodic, alarm, and/or update irqs 254 * rtc_handle_legacy_irq - AIE, UIE and PIE event hook
371 * @rtc: the rtc device 255 * @rtc: pointer to the rtc device
372 * @num: how many irqs are being reported (usually one) 256 *
373 * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF 257 * This function is called when an AIE, UIE or PIE mode interrupt
374 * Context: any 258 * has occured (or been emulated).
259 *
260 * Triggers the registered irq_task function callback.
375 */ 261 */
376void rtc_update_irq(struct rtc_device *rtc, 262static void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode)
377 unsigned long num, unsigned long events)
378{ 263{
379 unsigned long flags; 264 unsigned long flags;
380 265
266 /* mark one irq of the appropriate mode */
381 spin_lock_irqsave(&rtc->irq_lock, flags); 267 spin_lock_irqsave(&rtc->irq_lock, flags);
382 rtc->irq_data = (rtc->irq_data + (num << 8)) | events; 268 rtc->irq_data = (rtc->irq_data + (num << 8)) | (RTC_IRQF|mode);
383 spin_unlock_irqrestore(&rtc->irq_lock, flags); 269 spin_unlock_irqrestore(&rtc->irq_lock, flags);
384 270
271 /* call the task func */
385 spin_lock_irqsave(&rtc->irq_task_lock, flags); 272 spin_lock_irqsave(&rtc->irq_task_lock, flags);
386 if (rtc->irq_task) 273 if (rtc->irq_task)
387 rtc->irq_task->func(rtc->irq_task->private_data); 274 rtc->irq_task->func(rtc->irq_task->private_data);
@@ -390,6 +277,69 @@ void rtc_update_irq(struct rtc_device *rtc,
390 wake_up_interruptible(&rtc->irq_queue); 277 wake_up_interruptible(&rtc->irq_queue);
391 kill_fasync(&rtc->async_queue, SIGIO, POLL_IN); 278 kill_fasync(&rtc->async_queue, SIGIO, POLL_IN);
392} 279}
280
281
282/**
283 * rtc_aie_update_irq - AIE mode rtctimer hook
284 * @private: pointer to the rtc_device
285 *
286 * This functions is called when the aie_timer expires.
287 */
288void rtc_aie_update_irq(void *private)
289{
290 struct rtc_device *rtc = (struct rtc_device *)private;
291 rtc_handle_legacy_irq(rtc, 1, RTC_AF);
292}
293
294
295/**
296 * rtc_uie_update_irq - UIE mode rtctimer hook
297 * @private: pointer to the rtc_device
298 *
299 * This functions is called when the uie_timer expires.
300 */
301void rtc_uie_update_irq(void *private)
302{
303 struct rtc_device *rtc = (struct rtc_device *)private;
304 rtc_handle_legacy_irq(rtc, 1, RTC_UF);
305}
306
307
308/**
309 * rtc_pie_update_irq - PIE mode hrtimer hook
310 * @timer: pointer to the pie mode hrtimer
311 *
312 * This function is used to emulate PIE mode interrupts
313 * using an hrtimer. This function is called when the periodic
314 * hrtimer expires.
315 */
316enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer)
317{
318 struct rtc_device *rtc;
319 ktime_t period;
320 int count;
321 rtc = container_of(timer, struct rtc_device, pie_timer);
322
323 period = ktime_set(0, NSEC_PER_SEC/rtc->irq_freq);
324 count = hrtimer_forward_now(timer, period);
325
326 rtc_handle_legacy_irq(rtc, count, RTC_PF);
327
328 return HRTIMER_RESTART;
329}
330
331/**
332 * rtc_update_irq - Triggered when a RTC interrupt occurs.
333 * @rtc: the rtc device
334 * @num: how many irqs are being reported (usually one)
335 * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
336 * Context: any
337 */
338void rtc_update_irq(struct rtc_device *rtc,
339 unsigned long num, unsigned long events)
340{
341 schedule_work(&rtc->irqwork);
342}
393EXPORT_SYMBOL_GPL(rtc_update_irq); 343EXPORT_SYMBOL_GPL(rtc_update_irq);
394 344
395static int __rtc_match(struct device *dev, void *data) 345static int __rtc_match(struct device *dev, void *data)
@@ -476,18 +426,20 @@ int rtc_irq_set_state(struct rtc_device *rtc, struct rtc_task *task, int enabled
476 int err = 0; 426 int err = 0;
477 unsigned long flags; 427 unsigned long flags;
478 428
479 if (rtc->ops->irq_set_state == NULL)
480 return -ENXIO;
481
482 spin_lock_irqsave(&rtc->irq_task_lock, flags); 429 spin_lock_irqsave(&rtc->irq_task_lock, flags);
483 if (rtc->irq_task != NULL && task == NULL) 430 if (rtc->irq_task != NULL && task == NULL)
484 err = -EBUSY; 431 err = -EBUSY;
485 if (rtc->irq_task != task) 432 if (rtc->irq_task != task)
486 err = -EACCES; 433 err = -EACCES;
487 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
488 434
489 if (err == 0) 435 if (enabled) {
490 err = rtc->ops->irq_set_state(rtc->dev.parent, enabled); 436 ktime_t period = ktime_set(0, NSEC_PER_SEC/rtc->irq_freq);
437 hrtimer_start(&rtc->pie_timer, period, HRTIMER_MODE_REL);
438 } else {
439 hrtimer_cancel(&rtc->pie_timer);
440 }
441 rtc->pie_enabled = enabled;
442 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
491 443
492 return err; 444 return err;
493} 445}
@@ -508,21 +460,194 @@ int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq)
508 int err = 0; 460 int err = 0;
509 unsigned long flags; 461 unsigned long flags;
510 462
511 if (rtc->ops->irq_set_freq == NULL)
512 return -ENXIO;
513
514 spin_lock_irqsave(&rtc->irq_task_lock, flags); 463 spin_lock_irqsave(&rtc->irq_task_lock, flags);
515 if (rtc->irq_task != NULL && task == NULL) 464 if (rtc->irq_task != NULL && task == NULL)
516 err = -EBUSY; 465 err = -EBUSY;
517 if (rtc->irq_task != task) 466 if (rtc->irq_task != task)
518 err = -EACCES; 467 err = -EACCES;
519 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
520
521 if (err == 0) { 468 if (err == 0) {
522 err = rtc->ops->irq_set_freq(rtc->dev.parent, freq); 469 rtc->irq_freq = freq;
523 if (err == 0) 470 if (rtc->pie_enabled) {
524 rtc->irq_freq = freq; 471 ktime_t period;
472 hrtimer_cancel(&rtc->pie_timer);
473 period = ktime_set(0, NSEC_PER_SEC/rtc->irq_freq);
474 hrtimer_start(&rtc->pie_timer, period,
475 HRTIMER_MODE_REL);
476 }
525 } 477 }
478 spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
526 return err; 479 return err;
527} 480}
528EXPORT_SYMBOL_GPL(rtc_irq_set_freq); 481EXPORT_SYMBOL_GPL(rtc_irq_set_freq);
482
483/**
484 * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue
485 * @rtc rtc device
486 * @timer timer being added.
487 *
488 * Enqueues a timer onto the rtc devices timerqueue and sets
489 * the next alarm event appropriately.
490 *
491 * Must hold ops_lock for proper serialization of timerqueue
492 */
493void rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer)
494{
495 timerqueue_add(&rtc->timerqueue, &timer->node);
496 if (&timer->node == timerqueue_getnext(&rtc->timerqueue)) {
497 struct rtc_wkalrm alarm;
498 int err;
499 alarm.time = rtc_ktime_to_tm(timer->node.expires);
500 alarm.enabled = 1;
501 err = __rtc_set_alarm(rtc, &alarm);
502 if (err == -ETIME)
503 schedule_work(&rtc->irqwork);
504 }
505}
506
507/**
508 * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue
509 * @rtc rtc device
510 * @timer timer being removed.
511 *
512 * Removes a timer onto the rtc devices timerqueue and sets
513 * the next alarm event appropriately.
514 *
515 * Must hold ops_lock for proper serialization of timerqueue
516 */
517void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer)
518{
519 struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue);
520 timerqueue_del(&rtc->timerqueue, &timer->node);
521
522 if (next == &timer->node) {
523 struct rtc_wkalrm alarm;
524 int err;
525 next = timerqueue_getnext(&rtc->timerqueue);
526 if (!next)
527 return;
528 alarm.time = rtc_ktime_to_tm(next->expires);
529 alarm.enabled = 1;
530 err = __rtc_set_alarm(rtc, &alarm);
531 if (err == -ETIME)
532 schedule_work(&rtc->irqwork);
533 }
534}
535
536/**
537 * rtc_timer_do_work - Expires rtc timers
538 * @rtc rtc device
539 * @timer timer being removed.
540 *
541 * Expires rtc timers. Reprograms next alarm event if needed.
542 * Called via worktask.
543 *
544 * Serializes access to timerqueue via ops_lock mutex
545 */
546void rtc_timer_do_work(struct work_struct *work)
547{
548 struct rtc_timer *timer;
549 struct timerqueue_node *next;
550 ktime_t now;
551 struct rtc_time tm;
552
553 struct rtc_device *rtc =
554 container_of(work, struct rtc_device, irqwork);
555
556 mutex_lock(&rtc->ops_lock);
557again:
558 __rtc_read_time(rtc, &tm);
559 now = rtc_tm_to_ktime(tm);
560 while ((next = timerqueue_getnext(&rtc->timerqueue))) {
561 if (next->expires.tv64 > now.tv64)
562 break;
563
564 /* expire timer */
565 timer = container_of(next, struct rtc_timer, node);
566 timerqueue_del(&rtc->timerqueue, &timer->node);
567 timer->enabled = 0;
568 if (timer->task.func)
569 timer->task.func(timer->task.private_data);
570
571 /* Re-add/fwd periodic timers */
572 if (ktime_to_ns(timer->period)) {
573 timer->node.expires = ktime_add(timer->node.expires,
574 timer->period);
575 timer->enabled = 1;
576 timerqueue_add(&rtc->timerqueue, &timer->node);
577 }
578 }
579
580 /* Set next alarm */
581 if (next) {
582 struct rtc_wkalrm alarm;
583 int err;
584 alarm.time = rtc_ktime_to_tm(next->expires);
585 alarm.enabled = 1;
586 err = __rtc_set_alarm(rtc, &alarm);
587 if (err == -ETIME)
588 goto again;
589 }
590
591 mutex_unlock(&rtc->ops_lock);
592}
593
594
595/* rtc_timer_init - Initializes an rtc_timer
596 * @timer: timer to be intiialized
597 * @f: function pointer to be called when timer fires
598 * @data: private data passed to function pointer
599 *
600 * Kernel interface to initializing an rtc_timer.
601 */
602void rtc_timer_init(struct rtc_timer *timer, void (*f)(void* p), void* data)
603{
604 timerqueue_init(&timer->node);
605 timer->enabled = 0;
606 timer->task.func = f;
607 timer->task.private_data = data;
608}
609
610/* rtc_timer_start - Sets an rtc_timer to fire in the future
611 * @ rtc: rtc device to be used
612 * @ timer: timer being set
613 * @ expires: time at which to expire the timer
614 * @ period: period that the timer will recur
615 *
616 * Kernel interface to set an rtc_timer
617 */
618int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer* timer,
619 ktime_t expires, ktime_t period)
620{
621 int ret = 0;
622 mutex_lock(&rtc->ops_lock);
623 if (timer->enabled)
624 rtc_timer_remove(rtc, timer);
625
626 timer->node.expires = expires;
627 timer->period = period;
628
629 timer->enabled = 1;
630 rtc_timer_enqueue(rtc, timer);
631
632 mutex_unlock(&rtc->ops_lock);
633 return ret;
634}
635
636/* rtc_timer_cancel - Stops an rtc_timer
637 * @ rtc: rtc device to be used
638 * @ timer: timer being set
639 *
640 * Kernel interface to cancel an rtc_timer
641 */
642int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer* timer)
643{
644 int ret = 0;
645 mutex_lock(&rtc->ops_lock);
646 if (timer->enabled)
647 rtc_timer_remove(rtc, timer);
648 timer->enabled = 0;
649 mutex_unlock(&rtc->ops_lock);
650 return ret;
651}
652
653