[PATCH v2 0/6] ARM: at91: fix irq_pm_install_action WARNING

Boris Brezillon boris.brezillon at free-electrons.com
Mon Mar 2 01:18:12 PST 2015

My apologies to those of you who already received this series, but I
didn't increment the patch version and forgot some subsystem maintainers
and MLs.

Commit cab303be91dc47942bc25de33dc1140123540800 [1] introduced a WARN_ON
test which triggers a WARNING backtrace on at91 platforms.
While this WARN_ON is absolutely necessary to warn users that they should
not mix request with and without IRQF_NO_SUSPEND flags on shared IRQs,
there is no easy way to solve this issue on at91 platforms.

The main reason is that the init timer is often using a shared irq line
and thus request this irq with IRQF_NO_SUSPEND flag set, while other
peripherals request the same irq line without this flag.

This problem has recently been addressed by this patch [2] which adds
a new IRQF_COND_SUSPEND flag, that authorize mixing IRQF_NO_SUSPEND and
!IRQF_NO_SUSPEND as long as irq handlers setting IRQF_COND_SUSPEND
can safely be called in suspended state.

Doing this also implies taking care of system wakeup in devices handlers
if they tag the IRQ line as a wakeup source.
The first patch of this series exports the pm_system_wakeup symbol so
that drivers can call pm_system_wakeup from their interrupt handler.

This series then patches all at91 drivers that can have devices sharing
their IRQ line with a timer.

This series depends on [2].

Best Regards,



Changes since v1:
 - properly addressed wakeup handling in drivers

Boris Brezillon (6):
  PM / wakeup: export pm_system_wakeup symbol
  rtc: at91sam9: rework wakeup and interrupt handling
  rtc: at91rm9200: rework wakeup and interrupt handling
  clk: at91: implement suspend/resume for the PMC irqchip
  watchdog: at91sam9: request the irq with IRQF_NO_SUSPEND
  tty: serial: atmel: rework interrupt and wakeup handling

 drivers/base/power/wakeup.c       |  1 +
 drivers/clk/at91/pmc.c            | 20 ++++++++++-
 drivers/clk/at91/pmc.h            |  1 +
 drivers/rtc/rtc-at91rm9200.c      | 62 +++++++++++++++++++++++++--------
 drivers/rtc/rtc-at91sam9.c        | 73 ++++++++++++++++++++++++++++++++-------
 drivers/tty/serial/atmel_serial.c | 49 +++++++++++++++++++++++---
 drivers/watchdog/at91sam9_wdt.c   |  3 +-
 7 files changed, 177 insertions(+), 32 deletions(-)


More information about the linux-arm-kernel mailing list