On Wed, May 6, 2009 at 8:27 AM, Rafael J. Wysocki <rjw@xxxxxxx> wrote: > On Wednesday 06 May 2009, Kevin Hilman wrote: >> Arve Hjønnevåg <arve@xxxxxxxxxxx> writes: >> >> > On Tue, May 5, 2009 at 8:52 AM, Kevin Hilman >> > <khilman@xxxxxxxxxxxxxxxxxxx> wrote: >> >> Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> writes: >> >> >> >>> On Mon, 4 May 2009 17:27:04 -0700 Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx> wrote: >> >>> >> >>>> Interrupts that are flagged as wakeup sources via set_irq_wake() >> >>>> should not be disabled for suspend. >> >>>> >> >>> >> >>> Why not? >> >>> >> >> >> >> If an interrupt is a wakeup source, and it is disabled at the chip >> >> level, it will no longer generate interrupts, and thus no longer wake >> >> up the system. >> >> >> >> I'd be interested in hearing why wakeup interrupts should be disabled >> >> during suspend. > > That depends on whether or not they are used for anything else than wake-up. > >> >> [...] >> >> >>> >> >>> If this fixes some bug then please provide a description of that bug? >> >> >> >> The bug is that on TI OMAP, interrupts that are used for wakeup events >> >> are disabled by this code causing the system to no longer wake up. >> > >> > What do you do if the interrupt triggers right after your driver has >> > returned from its late suspend hook? >> >> If it's a wakeup IRQ, I assume you want it to prevent suspend. >> >> But I don't see how that can happen in the current code. IIUC, by the >> time your late suspend hook is run, your device IRQ is already >> disabled, so it won't trigger an interrupt that will be caught by >> check_wakeup_irqs() anyways. > > My understanding of __disable_irq() was that it didn't actually disable the > IRQ at the hardware level, allowing the CPU to actually receive the interrupt > and acknowledge it, but preventing the device driver for receiving it. Does > it work differently on the affected systems? Hi, Rafael. Sorry for bring the old issue but please let me ask you about suspend_device_irqs() function. __disable_irq() disables the IRQ at the hardware level in the following irq_chips i8259A_chip i8259_pic i8259A_chip bfin_internal_irqchip crisv10_irq_type crisv32_irq_type h8300irq_chip m_irq_chip mn10300_cpu_pic_level xtensa_irq_chip iop13xx_msi_chip msi_irq Because these irq_chips mask interrupts in 'disable' hook. Thus, your suspend_device_irqs() function disables all IRQs at the hardware level on all architectures which use irq_chips listed above in suspend state. Is this really what you wanted? If interrupt can wake up the system from suspend in some architectures and if disable_irq_wake is not supported in these architectures, I wonder if suspend_device_irqs() don't allow waking up by interrupt. Regards, Kyuwon _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
