rtc: make rtc_update_irq callable with irqs enabled

The rtc_update_irq() might be called with irqs enabled, if a interrupt
handler was registered without IRQF_DISABLED.  Use
spin_lock_irqsave/spin_unlock_irqrestore instead of spin_lock/spin_unlock.

Also update kerneldoc and drivers which do extra work to follow the
current interface spec, as suggestted by David Brownell.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Atsushi Nemoto 2009-06-18 16:49:09 -07:00 committed by Linus Torvalds
parent 575c5807f6
commit e6229bec25
6 changed files with 10 additions and 25 deletions

View File

@ -371,19 +371,21 @@ EXPORT_SYMBOL_GPL(rtc_update_irq_enable);
* @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
* Context: any
*/
void rtc_update_irq(struct rtc_device *rtc,
unsigned long num, unsigned long events)
{
spin_lock(&rtc->irq_lock);
rtc->irq_data = (rtc->irq_data + (num << 8)) | events;
spin_unlock(&rtc->irq_lock);
unsigned long flags;
spin_lock(&rtc->irq_task_lock);
spin_lock_irqsave(&rtc->irq_lock, flags);
rtc->irq_data = (rtc->irq_data + (num << 8)) | events;
spin_unlock_irqrestore(&rtc->irq_lock, flags);
spin_lock_irqsave(&rtc->irq_task_lock, flags);
if (rtc->irq_task)
rtc->irq_task->func(rtc->irq_task->private_data);
spin_unlock(&rtc->irq_task_lock);
spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
wake_up_interruptible(&rtc->irq_queue);
kill_fasync(&rtc->async_queue, SIGIO, POLL_IN);

View File

@ -60,8 +60,7 @@ static void rtc_uie_task(struct work_struct *work)
err = rtc_read_time(rtc, &tm);
local_irq_disable();
spin_lock(&rtc->irq_lock);
spin_lock_irq(&rtc->irq_lock);
if (rtc->stop_uie_polling || err) {
rtc->uie_task_active = 0;
} else if (rtc->oldsecs != tm.tm_sec) {
@ -74,10 +73,9 @@ static void rtc_uie_task(struct work_struct *work)
} else if (schedule_work(&rtc->uie_task) == 0) {
rtc->uie_task_active = 0;
}
spin_unlock(&rtc->irq_lock);
spin_unlock_irq(&rtc->irq_lock);
if (num)
rtc_update_irq(rtc, num, RTC_UF | RTC_IRQF);
local_irq_enable();
}
static void rtc_uie_timer(unsigned long data)
{

View File

@ -499,10 +499,7 @@ static void ds1305_work(struct work_struct *work)
if (!test_bit(FLAG_EXITING, &ds1305->flags))
enable_irq(spi->irq);
/* rtc_update_irq() requires an IRQ-disabled context */
local_irq_disable();
rtc_update_irq(ds1305->rtc, 1, RTC_AF | RTC_IRQF);
local_irq_enable();
}
/*

View File

@ -267,12 +267,7 @@ static void ds1307_work(struct work_struct *work)
control &= ~DS1337_BIT_A1IE;
i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, control);
/* rtc_update_irq() assumes that it is called
* from IRQ-disabled context.
*/
local_irq_disable();
rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
local_irq_enable();
}
out:

View File

@ -296,12 +296,7 @@ static void ds1374_work(struct work_struct *work)
control &= ~(DS1374_REG_CR_WACE | DS1374_REG_CR_AIE);
i2c_smbus_write_byte_data(client, DS1374_REG_CR, control);
/* rtc_update_irq() assumes that it is called
* from IRQ-disabled context.
*/
local_irq_disable();
rtc_update_irq(ds1374->rtc, 1, RTC_AF | RTC_IRQF);
local_irq_enable();
}
out:

View File

@ -93,7 +93,6 @@ static ssize_t test_irq_store(struct device *dev,
struct rtc_device *rtc = platform_get_drvdata(plat_dev);
retval = count;
local_irq_disable();
if (strncmp(buf, "tick", 4) == 0)
rtc_update_irq(rtc, 1, RTC_PF | RTC_IRQF);
else if (strncmp(buf, "alarm", 5) == 0)
@ -102,7 +101,6 @@ static ssize_t test_irq_store(struct device *dev,
rtc_update_irq(rtc, 1, RTC_UF | RTC_IRQF);
else
retval = -EINVAL;
local_irq_enable();
return retval;
}