On 22/10/2018 12:19, Dmitry Osipenko wrote: > On 10/22/18 12:52 PM, Thierry Reding wrote: >> On Fri, Oct 19, 2018 at 02:22:53PM +0100, Jon Hunter wrote: >>> From: Jonathan Hunter <jonathanh@xxxxxxxxxx> >>> >>> The tps6586x driver creates an irqchip that is used by its various child >>> devices for managing interrupts. The tps6586x-rtc device is one of its >>> children that uses the tps6586x irqchip. When using the tps6586x-rtc as >>> a wake-up device from suspend, the following is seen: >>> >>> PM: Syncing filesystems ... done. >>> Freezing user space processes ... (elapsed 0.001 seconds) done. >>> OOM killer disabled. >>> Freezing remaining freezable tasks ... (elapsed 0.000 seconds) done. >>> Disabling non-boot CPUs ... >>> Entering suspend state LP1 >>> Enabling non-boot CPUs ... >>> CPU1 is up >>> tps6586x 3-0034: failed to read interrupt status >>> tps6586x 3-0034: failed to read interrupt status >>> >>> The reason why the tps6586x interrupt status cannot be read is because >>> the tps6586x interrupt is not masked during suspend and when the >>> tps6586x-rtc interrupt occurs, to wake-up the device, the interrupt is >>> seen before the i2c controller has been resumed in order to read the >>> tps6586x interrupt status. >>> >>> The tps6586x-rtc driver sets it's interrupt as a wake-up source during >>> suspend, which gets propagated to the parent tps6586x interrupt. >>> However, the tps6586x-rtc driver cannot disable it's interrupt during >>> suspend otherwise we would never be woken up and so the tps6586x must >>> disable it's interrupt instead. >>> >>> Prevent the tps6586x interrupt handler from executing on exiting suspend >>> before the i2c controller has been resumed by disabling the tps6586x >>> interrupt on entering suspend and re-enabling it on resuming from >>> suspend. >>> >>> Cc: stable@xxxxxxxxxxxxxxx >>> >>> Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx> >>> --- >>> drivers/mfd/tps6586x.c | 24 ++++++++++++++++++++++++ >>> 1 file changed, 24 insertions(+) >> >> So does this mean that the SPI interrupt for the PMIC can still be a >> wakeup source even if it is masked? This is slightly odd because now >> you're saying that this does work while it doesn't work for the RTC >> interrupt. So is this an implementation quirk of the LIC/GIC on Tegra >> which doesn't extend to the TPS6586x? Or am I missing something? > > What is the expected behaviour of IRQ disabling? Should it disable wakeup ability or only mask IRQ handling? I believe only mask the interrupt. However, the caveat here could be if the parent interrupt controller actually supports wake-up. For Tegra it is the LIC that handles the wake-up. > Couple months ago disabling of IRQ was disabling the wakeup, now something has been changed in kernel and wakeup isn't getting disabled. So either there was a bug before that was fixed or there is a bug now. Are you sure you were disabling the PMIC host interrupt? If you disable the RTC interrupt in the PMIC's RTC driver, then this will prevent the wake-up from occurring because you are masking the interrupt within the PMIC and so it will never generate an interrupt to the host. Cheers Jon -- nvpublic
