* Ladislav Michl <ladis@xxxxxxxxxxxxxx> [170320 17:19]: > On Mon, Mar 20, 2017 at 04:16:33PM -0500, Grygorii Strashko wrote: > > > > > > On 03/20/2017 06:21 AM, Ladislav Michl wrote: > > > On Thu, Mar 16, 2017 at 12:17:45PM -0700, Tony Lindgren wrote: > > >> Hmm maybe we need to flush posted writes when re-enabling the GPIO interrupts? > > >> > > >> Below is an untested patch that might help if that's the case. > > > > > > Unfortunately that's not the case. Even writing set&clear version of > > > interrupt demux handler did not make it any better. And idea from > > > ancient patch I initially sent is not easily extensible when we > > > need to trigger interrupt on both edges. So far I'm clueless... > > > > So, just to be sure - can you reproduce it with LKML? > > Do you mean mainline kernel? I'm on 4.11-rc3 now... > > > As per code, the possible problem could be with double acking of edge irqs > > (theoretically): > > - omap_gpio_irq_handler > > - "isr" = read irq status > > - omap_clear_gpio_irqbank(bank, isr_saved & ~level_mask); --- clear edge status, so new irq can be accepted > > - loop while "isr" > > generic_handle_irq() > > - handle_edge_irq() > > - desc->irq_data.chip->irq_ack(&desc->irq_data); > > - omap_gpio_ack_irq() > > it might be that at this moment edge IRQ was triggered again and it will be cleared. > > > > just as an experiment, could you try to update omap_gpio_ack_irq() > > as below: > > > > if (irq type is not edge) > > omap_clear_gpio_irqstatus(bank, offset); > > Rewritten as: > > diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c > index efc85a279d54..9381763e1fec 100644 > --- a/drivers/gpio/gpio-omap.c > +++ b/drivers/gpio/gpio-omap.c > @@ -806,7 +806,8 @@ static void omap_gpio_ack_irq(struct irq_data *d) > struct gpio_bank *bank = omap_irq_data_get_bank(d); > unsigned offset = d->hwirq; > > - omap_clear_gpio_irqstatus(bank, offset); > + if (bank->level_mask & BIT(offset)) > + omap_clear_gpio_irqstatus(bank, offset); > } > > static void omap_gpio_mask_irq(struct irq_data *d) > > And that did the trick. So far I tried IR decoder and decoding sometimes > fails, but I cannot say anything certain until I check with scope (which > I do tomorrow) Another good code review catch by Grygorii! :) Can you guys please add a comment there to the code when posting the proper patch? Something like: /* * Edge GPIOs are already cleared during handling, clearing * them here again will cause lost interrupts. */ And also add a proper Fixes tag so this gets propagated to the stable kernels. It really seems we've had this for a long time. Regards, Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
