| Message ID | 1496147943-25822-9-git-send-email-kgunda@codeaurora.org (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | Andy Gross |
| Headers | show |
On 05/30, Kiran Gunda wrote: > From: Abhijeet Dharmapurikar <adharmap@codeaurora.org> > > The current code uses handle_level_irq flow handler even if the > trigger type of the interrupt is edge. This can lead to missing > of an edge transition that happens when the interrupt is being > handled. The level flow handler masks the interrupt while it is > being handled, so if an edge transition happens at that time, > that edge is lost. > > Use an edge flow handler for edge type interrupts which ensures > that the interrupt stays enabled while being handled - at least > until it triggers at which point the flow handler sets the > IRQF_PENDING flag and only then masks the interrupt. That > IRQF_PENDING state indicates an edge transition happened while > the interrupt was being handled and the handler is called again. > > Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org> > Signed-off-by: Kiran Gunda <kgunda@codeaurora.org> Do we have any edge interrupts in the tree right now? At least RTC seems to be using edge... This should go back to stable with a Fixes tag. > --- > drivers/spmi/spmi-pmic-arb.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/spmi/spmi-pmic-arb.c b/drivers/spmi/spmi-pmic-arb.c > index 1d23df0..ad34491 100644 > --- a/drivers/spmi/spmi-pmic-arb.c > +++ b/drivers/spmi/spmi-pmic-arb.c > @@ -625,6 +625,12 @@ static int qpnpint_irq_set_type(struct irq_data *d, unsigned int flow_type) > } > > qpnpint_spmi_write(d, QPNPINT_REG_SET_TYPE, &type, sizeof(type)); > + > + if (flow_type & IRQ_TYPE_EDGE_BOTH) IRQ_TYPE_EDGE_BOTH doesn't seem appropriate to use here. We're really just testing to see if the type is an edge type, not if it's BOTH edges. > + irq_set_handler_locked(d, handle_edge_irq); > + else > + irq_set_handler_locked(d, handle_level_irq); > + And we already have code that does that check: if (flow_type & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)) so just put the irq_set_handler_locked() calls in those if statements please.
On 2017-06-01 00:33, Stephen Boyd wrote: > On 05/30, Kiran Gunda wrote: >> From: Abhijeet Dharmapurikar <adharmap@codeaurora.org> >> >> The current code uses handle_level_irq flow handler even if the >> trigger type of the interrupt is edge. This can lead to missing >> of an edge transition that happens when the interrupt is being >> handled. The level flow handler masks the interrupt while it is >> being handled, so if an edge transition happens at that time, >> that edge is lost. >> >> Use an edge flow handler for edge type interrupts which ensures >> that the interrupt stays enabled while being handled - at least >> until it triggers at which point the flow handler sets the >> IRQF_PENDING flag and only then masks the interrupt. That >> IRQF_PENDING state indicates an edge transition happened while >> the interrupt was being handled and the handler is called again. >> >> Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org> >> Signed-off-by: Kiran Gunda <kgunda@codeaurora.org> > > Do we have any edge interrupts in the tree right now? At least > RTC seems to be using edge... This should go back to stable with > a Fixes tag. > Yes. A bunch of internal drivers use edge interrupts. >> --- >> drivers/spmi/spmi-pmic-arb.c | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/drivers/spmi/spmi-pmic-arb.c >> b/drivers/spmi/spmi-pmic-arb.c >> index 1d23df0..ad34491 100644 >> --- a/drivers/spmi/spmi-pmic-arb.c >> +++ b/drivers/spmi/spmi-pmic-arb.c >> @@ -625,6 +625,12 @@ static int qpnpint_irq_set_type(struct irq_data >> *d, unsigned int flow_type) >> } >> >> qpnpint_spmi_write(d, QPNPINT_REG_SET_TYPE, &type, sizeof(type)); >> + >> + if (flow_type & IRQ_TYPE_EDGE_BOTH) > > IRQ_TYPE_EDGE_BOTH doesn't seem appropriate to use here. We're > really just testing to see if the type is an edge type, not if > it's BOTH edges. > Ok. Agree. Will fix in the follow up patch. >> + irq_set_handler_locked(d, handle_edge_irq); >> + else >> + irq_set_handler_locked(d, handle_level_irq); >> + > > And we already have code that does that check: > > if (flow_type & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)) > > so just put the irq_set_handler_locked() calls in those if > statements please. Sure. Will fix in the follow up patch. -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/spmi/spmi-pmic-arb.c b/drivers/spmi/spmi-pmic-arb.c index 1d23df0..ad34491 100644 --- a/drivers/spmi/spmi-pmic-arb.c +++ b/drivers/spmi/spmi-pmic-arb.c @@ -625,6 +625,12 @@ static int qpnpint_irq_set_type(struct irq_data *d, unsigned int flow_type) } qpnpint_spmi_write(d, QPNPINT_REG_SET_TYPE, &type, sizeof(type)); + + if (flow_type & IRQ_TYPE_EDGE_BOTH) + irq_set_handler_locked(d, handle_edge_irq); + else + irq_set_handler_locked(d, handle_level_irq); + return 0; }