[PATCH 0/6] rtc: Fix problems with missing UIE irqs

Esben Haabendal
2024-12-03T10:45:55Z

This fixes a couple of different problems, that can cause RTC (alarm)
irqs to be missing when generating UIE interrupts.

The first commit fixes a long-standing problem, which has been
documented in a comment since 2010. This fixes a race that could cause
UIE irqs to stop being generated, which was easily reproduced by
timing the use of RTC_UIE_ON ioctl with the seconds tick in the RTC.

The last commit ensures that RTC (alarm) irqs are enabled whenever
RTC_UIE_ON ioctl is used.

The driver specific commits avoids kernel warnings about unbalanced
enable_irq/disable_irq, which gets triggered on first RTC_UIE_ON with
the last commit. Before this series, the same warning should be seen
on initial RTC_AIE_ON with those drivers.

Signed-off-by: Esben Haabendal <esben@geanix.com>
---
Esben Haabendal (6):
rtc: interface: Fix long-standing race when setting alarm
rtc: isl12022: Fix initial enable_irq/disable_irq balance
rtc: cpcap: Fix initial enable_irq/disable_irq balance
rtc: st-lpc: Fix initial enable_irq/disable_irq balance
rtc: tps6586x: Fix initial enable_irq/disable_irq balance
rtc: interface: Ensure alarm irq is enabled when UIE is enabled

drivers/rtc/interface.c | 27 +++++++++++++++++++++++++++
drivers/rtc/rtc-cpcap.c | 1 +
drivers/rtc/rtc-isl12022.c | 1 +
drivers/rtc/rtc-st-lpc.c | 1 +
drivers/rtc/rtc-tps6586x.c | 1 +
5 files changed, 31 insertions(+)
---
base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37
change-id: 20241203-rtc-uie-irq-fixes-f2838782d0f8

Best regards,
--
Esben Haabendal <esben@geanix.com>