*/
#include <linux/rtc.h>
+#include <linux/log2.h>
-int rtc_read_time(struct class_device *class_dev, struct rtc_time *tm)
+int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
{
int err;
- struct rtc_device *rtc = to_rtc_device(class_dev);
err = mutex_lock_interruptible(&rtc->ops_lock);
if (err)
err = -EINVAL;
else {
memset(tm, 0, sizeof(struct rtc_time));
- err = rtc->ops->read_time(class_dev->dev, tm);
+ err = rtc->ops->read_time(rtc->dev.parent, tm);
}
mutex_unlock(&rtc->ops_lock);
}
EXPORT_SYMBOL_GPL(rtc_read_time);
-int rtc_set_time(struct class_device *class_dev, struct rtc_time *tm)
+int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm)
{
int err;
- struct rtc_device *rtc = to_rtc_device(class_dev);
err = rtc_valid_tm(tm);
if (err != 0)
else if (!rtc->ops->set_time)
err = -EINVAL;
else
- err = rtc->ops->set_time(class_dev->dev, tm);
+ err = rtc->ops->set_time(rtc->dev.parent, tm);
mutex_unlock(&rtc->ops_lock);
return err;
}
EXPORT_SYMBOL_GPL(rtc_set_time);
-int rtc_set_mmss(struct class_device *class_dev, unsigned long secs)
+int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs)
{
int err;
- struct rtc_device *rtc = to_rtc_device(class_dev);
err = mutex_lock_interruptible(&rtc->ops_lock);
if (err)
if (!rtc->ops)
err = -ENODEV;
else if (rtc->ops->set_mmss)
- err = rtc->ops->set_mmss(class_dev->dev, secs);
+ err = rtc->ops->set_mmss(rtc->dev.parent, secs);
else if (rtc->ops->read_time && rtc->ops->set_time) {
struct rtc_time new, old;
- err = rtc->ops->read_time(class_dev->dev, &old);
+ err = rtc->ops->read_time(rtc->dev.parent, &old);
if (err == 0) {
rtc_time_to_tm(secs, &new);
*/
if (!((old.tm_hour == 23 && old.tm_min == 59) ||
(new.tm_hour == 23 && new.tm_min == 59)))
- err = rtc->ops->set_time(class_dev->dev, &new);
+ err = rtc->ops->set_time(rtc->dev.parent,
+ &new);
}
}
else
}
EXPORT_SYMBOL_GPL(rtc_set_mmss);
-int rtc_read_alarm(struct class_device *class_dev, struct rtc_wkalrm *alarm)
+static int rtc_read_alarm_internal(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
{
int err;
- struct rtc_device *rtc = to_rtc_device(class_dev);
err = mutex_lock_interruptible(&rtc->ops_lock);
if (err)
err = -EINVAL;
else {
memset(alarm, 0, sizeof(struct rtc_wkalrm));
- err = rtc->ops->read_alarm(class_dev->dev, alarm);
+ err = rtc->ops->read_alarm(rtc->dev.parent, alarm);
}
mutex_unlock(&rtc->ops_lock);
return err;
}
+
+int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
+{
+ int err;
+ struct rtc_time before, now;
+ int first_time = 1;
+
+ /* The lower level RTC driver may not be capable of filling
+ * in all fields of the rtc_time struct (eg. rtc-cmos),
+ * and so might instead return -1 in some fields.
+ * We deal with that here by grabbing a current RTC timestamp
+ * and using values from that for any missing (-1) values.
+ *
+ * But this can be racey, because some fields of the RTC timestamp
+ * may have wrapped in the interval since we read the RTC alarm,
+ * which would lead to us inserting inconsistent values in place
+ * of the -1 fields.
+ *
+ * Reading the alarm and timestamp in the reverse sequence
+ * would have the same race condition, and not solve the issue.
+ *
+ * So, we must first read the RTC timestamp,
+ * then read the RTC alarm value,
+ * and then read a second RTC timestamp.
+ *
+ * If any fields of the second timestamp have changed
+ * when compared with the first timestamp, then we know
+ * our timestamp may be inconsistent with that used by
+ * the low-level rtc_read_alarm_internal() function.
+ *
+ * So, when the two timestamps disagree, we just loop and do
+ * the process again to get a fully consistent set of values.
+ *
+ * This could all instead be done in the lower level driver,
+ * but since more than one lower level RTC implementation needs it,
+ * then it's probably best best to do it here instead of there..
+ */
+
+ /* Get the "before" timestamp */
+ err = rtc_read_time(rtc, &before);
+ if (err < 0)
+ return err;
+ do {
+ if (!first_time)
+ memcpy(&before, &now, sizeof(struct rtc_time));
+ first_time = 0;
+
+ /* get the RTC alarm values, which may be incomplete */
+ err = rtc_read_alarm_internal(rtc, alarm);
+ if (err)
+ return err;
+ if (!alarm->enabled)
+ return 0;
+
+ /* get the "after" timestamp, to detect wrapped fields */
+ err = rtc_read_time(rtc, &now);
+ if (err < 0)
+ return err;
+
+ /* note that tm_sec is a "don't care" value here: */
+ } while ( before.tm_min != now.tm_min
+ || before.tm_hour != now.tm_hour
+ || before.tm_mon != now.tm_mon
+ || before.tm_year != now.tm_year
+ || before.tm_isdst != now.tm_isdst);
+
+ /* Fill in any missing alarm fields using the timestamp */
+ if (alarm->time.tm_sec == -1)
+ alarm->time.tm_sec = now.tm_sec;
+ if (alarm->time.tm_min == -1)
+ alarm->time.tm_min = now.tm_min;
+ if (alarm->time.tm_hour == -1)
+ alarm->time.tm_hour = now.tm_hour;
+ if (alarm->time.tm_mday == -1)
+ alarm->time.tm_mday = now.tm_mday;
+ if (alarm->time.tm_mon == -1)
+ alarm->time.tm_mon = now.tm_mon;
+ if (alarm->time.tm_year == -1)
+ alarm->time.tm_year = now.tm_year;
+ return 0;
+}
EXPORT_SYMBOL_GPL(rtc_read_alarm);
-int rtc_set_alarm(struct class_device *class_dev, struct rtc_wkalrm *alarm)
+int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
{
int err;
- struct rtc_device *rtc = to_rtc_device(class_dev);
+
+ err = rtc_valid_tm(&alarm->time);
+ if (err != 0)
+ return err;
err = mutex_lock_interruptible(&rtc->ops_lock);
if (err)
else if (!rtc->ops->set_alarm)
err = -EINVAL;
else
- err = rtc->ops->set_alarm(class_dev->dev, alarm);
+ err = rtc->ops->set_alarm(rtc->dev.parent, alarm);
mutex_unlock(&rtc->ops_lock);
return err;
/**
* rtc_update_irq - report RTC periodic, alarm, and/or update irqs
- * @class_dev: the rtc's class device
+ * @rtc: the rtc device
* @num: how many irqs are being reported (usually one)
* @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
* Context: in_interrupt(), irqs blocked
*/
-void rtc_update_irq(struct class_device *class_dev,
+void rtc_update_irq(struct rtc_device *rtc,
unsigned long num, unsigned long events)
{
- struct rtc_device *rtc = to_rtc_device(class_dev);
-
spin_lock(&rtc->irq_lock);
rtc->irq_data = (rtc->irq_data + (num << 8)) | events;
spin_unlock(&rtc->irq_lock);
}
EXPORT_SYMBOL_GPL(rtc_update_irq);
-struct class_device *rtc_class_open(char *name)
+static int __rtc_match(struct device *dev, void *data)
{
- struct class_device *class_dev = NULL,
- *class_dev_tmp;
-
- down(&rtc_class->sem);
- list_for_each_entry(class_dev_tmp, &rtc_class->children, node) {
- if (strncmp(class_dev_tmp->class_id, name, BUS_ID_SIZE) == 0) {
- class_dev = class_device_get(class_dev_tmp);
- break;
- }
- }
+ char *name = (char *)data;
+
+ if (strncmp(dev->bus_id, name, BUS_ID_SIZE) == 0)
+ return 1;
+ return 0;
+}
+
+struct rtc_device *rtc_class_open(char *name)
+{
+ struct device *dev;
+ struct rtc_device *rtc = NULL;
- if (class_dev) {
- if (!try_module_get(to_rtc_device(class_dev)->owner))
- class_dev = NULL;
+ dev = class_find_device(rtc_class, name, __rtc_match);
+ if (dev)
+ rtc = to_rtc_device(dev);
+
+ if (rtc) {
+ if (!try_module_get(rtc->owner)) {
+ put_device(dev);
+ rtc = NULL;
+ }
}
- up(&rtc_class->sem);
- return class_dev;
+ return rtc;
}
EXPORT_SYMBOL_GPL(rtc_class_open);
-void rtc_class_close(struct class_device *class_dev)
+void rtc_class_close(struct rtc_device *rtc)
{
- module_put(to_rtc_device(class_dev)->owner);
- class_device_put(class_dev);
+ module_put(rtc->owner);
+ put_device(&rtc->dev);
}
EXPORT_SYMBOL_GPL(rtc_class_close);
-int rtc_irq_register(struct class_device *class_dev, struct rtc_task *task)
+int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task)
{
int retval = -EBUSY;
- struct rtc_device *rtc = to_rtc_device(class_dev);
if (task == NULL || task->func == NULL)
return -EINVAL;
+ /* Cannot register while the char dev is in use */
+ if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags))
+ return -EBUSY;
+
spin_lock_irq(&rtc->irq_task_lock);
if (rtc->irq_task == NULL) {
rtc->irq_task = task;
}
spin_unlock_irq(&rtc->irq_task_lock);
+ clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
+
return retval;
}
EXPORT_SYMBOL_GPL(rtc_irq_register);
-void rtc_irq_unregister(struct class_device *class_dev, struct rtc_task *task)
+void rtc_irq_unregister(struct rtc_device *rtc, struct rtc_task *task)
{
- struct rtc_device *rtc = to_rtc_device(class_dev);
-
spin_lock_irq(&rtc->irq_task_lock);
if (rtc->irq_task == task)
rtc->irq_task = NULL;
}
EXPORT_SYMBOL_GPL(rtc_irq_unregister);
-int rtc_irq_set_state(struct class_device *class_dev, struct rtc_task *task, int enabled)
+/**
+ * rtc_irq_set_state - enable/disable 2^N Hz periodic IRQs
+ * @rtc: the rtc device
+ * @task: currently registered with rtc_irq_register()
+ * @enabled: true to enable periodic IRQs
+ * Context: any
+ *
+ * Note that rtc_irq_set_freq() should previously have been used to
+ * specify the desired frequency of periodic IRQ task->func() callbacks.
+ */
+int rtc_irq_set_state(struct rtc_device *rtc, struct rtc_task *task, int enabled)
{
int err = 0;
unsigned long flags;
- struct rtc_device *rtc = to_rtc_device(class_dev);
if (rtc->ops->irq_set_state == NULL)
return -ENXIO;
spin_lock_irqsave(&rtc->irq_task_lock, flags);
+ if (rtc->irq_task != NULL && task == NULL)
+ err = -EBUSY;
if (rtc->irq_task != task)
- err = -ENXIO;
+ err = -EACCES;
spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
if (err == 0)
- err = rtc->ops->irq_set_state(class_dev->dev, enabled);
+ err = rtc->ops->irq_set_state(rtc->dev.parent, enabled);
return err;
}
EXPORT_SYMBOL_GPL(rtc_irq_set_state);
-int rtc_irq_set_freq(struct class_device *class_dev, struct rtc_task *task, int freq)
+/**
+ * rtc_irq_set_freq - set 2^N Hz periodic IRQ frequency for IRQ
+ * @rtc: the rtc device
+ * @task: currently registered with rtc_irq_register()
+ * @freq: positive frequency with which task->func() will be called
+ * Context: any
+ *
+ * Note that rtc_irq_set_state() is used to enable or disable the
+ * periodic IRQs.
+ */
+int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq)
{
int err = 0;
unsigned long flags;
- struct rtc_device *rtc = to_rtc_device(class_dev);
if (rtc->ops->irq_set_freq == NULL)
return -ENXIO;
+ if (!is_power_of_2(freq))
+ return -EINVAL;
+
spin_lock_irqsave(&rtc->irq_task_lock, flags);
+ if (rtc->irq_task != NULL && task == NULL)
+ err = -EBUSY;
if (rtc->irq_task != task)
- err = -ENXIO;
+ err = -EACCES;
spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
if (err == 0) {
- err = rtc->ops->irq_set_freq(class_dev->dev, freq);
+ err = rtc->ops->irq_set_freq(rtc->dev.parent, freq);
if (err == 0)
rtc->irq_freq = freq;
}
git.openpandora.org / pandora-kernel.git / blobdiff