Messages in this thread | | | Date | Wed, 5 Feb 2020 08:34:10 -0700 | From | Lina Iyer <> | Subject | Re: [PATCH] genirq: Clarify that irq wake state is orthogonal to enable/disable |
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On Wed, Feb 05 2020 at 05:27 -0700, Thomas Gleixner wrote: >Stephen Boyd <swboyd@chromium.org> writes: >> There's some confusion around if an irq that's disabled with >> disable_irq() can still wake the system from sleep states such as >> "suspend to RAM". Let's clarify this in the kernel documentation for >> irq_set_irq_wake() so that it's clear that an irq can be disabled and >> still wake the system if it has been marked for wakeup. >> >> Cc: Marc Zyngier <maz@kernel.org> >> Cc: Douglas Anderson <dianders@chromium.org> >> Cc: Lina Iyer <ilina@codeaurora.org> >> Cc: Maulik Shah <mkshah@codeaurora.org> >> Signed-off-by: Stephen Boyd <swboyd@chromium.org> >> --- >> kernel/irq/manage.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c >> index 818b2802d3e7..fa8db98c8699 100644 >> --- a/kernel/irq/manage.c >> +++ b/kernel/irq/manage.c >> @@ -731,6 +731,11 @@ static int set_irq_wake_real(unsigned int irq, unsigned int on) >> * >> * Wakeup mode lets this IRQ wake the system from sleep >> * states like "suspend to RAM". >> + * >> + * Note: irq enable/disable state is completely orthogonal >> + * to the enable/disable state of irq wake. An irq can be >> + * disabled with disable_irq() and still wake the system as >> + * long as the irq has wake enabled. > >It clearly should say that this is really depending on the hardware >implementation of the particual interrupt chip whether disabled + wake >mode is supported. > Could an irqchip flag be used to warn users that we may not wakeup from suspend/resume if the interrupt if the hardware does not support wakeup when disabled ?
--Lina
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