On Wed, Jun 12, 2019 at 8:34 AM Tony Lindgren <tony@xxxxxxxxxxx> wrote: > If an edge interrupt triggers while entering idle just before we save > GPIO datain register to saved_datain, the triggered GPIO will not be > noticed on wake-up. This is because the saved_datain and GPIO datain > are the same on wake-up in omap_gpio_unidle(). Let's fix this by > ignoring any pending edge interrupts for saved_datain. > > This issue affects only idle states where the GPIO module internal > wake-up path is operational. For deeper idle states where the GPIO > module gets powered off, Linux generic wakeirqs must be used for > the padconf wake-up events with pinctrl-single driver. For examples, > please see "interrupts-extended" dts usage in many drivers. > > This issue can be somewhat easily reproduced by pinging an idle system > with smsc911x Ethernet interface configured IRQ_TYPE_EDGE_FALLING. At > some point the smsc911x interrupts will just stop triggering. Also if > WLCORE WLAN is used with EDGE interrupt like it's documentation specifies, > we can see lost interrupts without this patch. > > Note that in the long run we may be able to cancel entering idle by > returning an error in gpio_omap_cpu_notifier() on pending interrupts. > But let's fix the bug first. > > Also note that because of the recent clean-up efforts this patch does > not apply directly to older kernels. This does fix a long term issue > though, and can be backported as needed. > > Cc: Aaro Koskinen <aaro.koskinen@xxxxxx> > Cc: Grygorii Strashko <grygorii.strashko@xxxxxx> > Cc: Keerthy <j-keerthy@xxxxxx> > Cc: Ladislav Michl <ladis@xxxxxxxxxxxxxx> > Cc: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > Cc: Russell King <rmk+kernel@xxxxxxxxxxxxxxx> > Cc: Tero Kristo <t-kristo@xxxxxx> > Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Patch applied. Let's see if this nails it. Yours, Linus Walleij
