Commit e6229bec authored by Atsushi Nemoto's avatar Atsushi Nemoto Committed by Linus Torvalds
Browse files

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: default avatarAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 575c5807

drivers/rtc/interface.c

+7 −5
Original line number Diff line number Diff line
@@ -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);

	unsigned long flags;



	spin_lock_irqsave(&rtc->irq_lock, flags);

	rtc->irq_data = (rtc->irq_data + (num << 8)) | events;

	spin_unlock(&rtc->irq_lock);

	spin_unlock_irqrestore(&rtc->irq_lock, flags);



	spin_lock(&rtc->irq_task_lock);

	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);

drivers/rtc/rtc-dev.c

+2 −4
Original line number Diff line number Diff line
@@ -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)

{

drivers/rtc/rtc-ds1305.c

+0 −3
Original line number Diff line number Diff line
@@ -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();

}



/*

drivers/rtc/rtc-ds1307.c

+0 −5
Original line number Diff line number Diff line
@@ -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:

drivers/rtc/rtc-ds1374.c

+0 −5
Original line number Diff line number Diff line
@@ -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:

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