On 1/12/2015 8:04 AM, Geert Uytterhoeven wrote:
If no_irq_chip or dummy_irq_chip are used for wake up (e.g. gpio-keys
with a simple GPIO controller), the following warning is printed on
resume from s2ram:
WANING: CPU: 0 PID: 1046 at kernel/irq/manage.c:537 irq_set_irq_wake+0x9c/0xf8()
Unbalanced IRQ 113 wake disable
This happens because no_irq_chip and dummy_irq_chip do not implement
irq_chip.irq_set_wake(), causing set_irq_wake_real() to return -ENXIO,
and irq_set_irq_wake() to reset the wake_depth to zero.
Set IRQCHIP_SKIP_SET_WAKE to indicate that irq_chip.irq_set_wake() is
not implemented.
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
Alternatively, can't we remove IRQCHIP_SKIP_SET_WAKE, and just check for
the presence of irq_chip.irq_set_wake()?
I'll be happy to send a patch to do that instead...
Is there anything that relies on this -ENXIO error code?
All irq_chip implementations that set IRQCHIP_SKIP_SET_WAKE do not
implement irq_chip.irq_set_wake(). There are probably more of them that
forgot to set IRQCHIP_SKIP_SET_WAKE though.
Am I missing something?
Commit 60f96b41f71d2a13 ("genirq: Add IRQCHIP_SKIP_SET_WAKE flag")
doesn't explain why adding the flag was chosen.
The flag was added to avoid dummy irq_set_wake() implementation
as described in the commit.
------------------
commit 60f96b41f71d2a13d1c0a457b8b77958f77142d1
Author: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Date: Fri Sep 9 13:59:35 2011 +0530
genirq: Add IRQCHIP_SKIP_SET_WAKE flag
Some irq chips need the irq_set_wake() functionality, but do not
require a irq_set_wake() callback. Instead of forcing an empty
callback to be implemented add a flag which notes this fact. Check for
the flag in set_irq_wake_real() and return success when set.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
------------------
Here is the relevant thread.
http://lists.infradead.org/pipermail/linux-arm-kernel/2011-September/064590.html
As you can read from thread, the idea is to handle the need at
genirq level. Either with a flag or a dummy function.
Hope this helps.
Regards,
Santosh
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
