Re: [RESEND PATCH v3 02/10] spmi: pmic-arb: do not ack and clear peripheral interrupts in cleanup_irq

[Fenglin Wu]

On 2021/12/2 10:39, Bryan O'Donoghue wrote:
> On 02/12/2021 00:00, Fenglin Wu wrote:
> > From: Subbaraman Narayanamurthy <subbaram@xxxxxxxxxxxxxx>
> >
> > Currently, cleanup_irq() is invoked when a peripheral's interrupt
> > fires and there is no mapping present in the interrupt domain of
> > spmi interrupt controller.
> >
> > The cleanup_irq clears the arbiter bit, clears the pmic interrupt
> > and disables it at the pmic in that order. The last disable in
> > cleanup_irq races with request_irq() in that it stomps over the
> > enable issued by request_irq. Fix this by not writing to the pmic
> > in cleanup_irq. The latched bit will be left set in the pmic,
> > which will not send us more interrupts even if the enable bit
> > stays enabled.
> >
> > When a client wants to request an interrupt, use the activate
> > callback on the irq_domain to clear latched bit. This ensures
> > that the latched, if set due to the above changes in cleanup_irq
> > or when the bootloader leaves it set, gets cleaned up, paving way
> > for upcoming interrupts to trigger.
> >
> > With this, there is a possibility of unwanted triggering of
> > interrupt right after the latched bit is cleared - the interrupt
> > may be left enabled too. To avoid that, clear the enable first
> > followed by clearing the latched bit in the activate callback.
> >
> > Signed-off-by: Subbaraman Narayanamurthy <subbaram@xxxxxxxxxxxxxx>
> > [collinsd@xxxxxxxxxxxxxx: fix merge conflict]
> > Signed-off-by: David Collins <collinsd@xxxxxxxxxxxxxx>
> > Signed-off-by: Fenglin Wu <quic_fenglinw@xxxxxxxxxxx>
> > ---
> >   drivers/spmi/spmi-pmic-arb.c | 15 +++++----------
> >   1 file changed, 5 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/spmi/spmi-pmic-arb.c b/drivers/spmi/spmi-pmic-arb.c
> > index da629cc..ce7ae99 100644
> > --- a/drivers/spmi/spmi-pmic-arb.c
> > +++ b/drivers/spmi/spmi-pmic-arb.c
> > @@ -492,16 +492,6 @@ static void cleanup_irq(struct spmi_pmic_arb 
> > *pmic_arb, u16 apid, int id)
> >       dev_err_ratelimited(&pmic_arb->spmic->dev, "%s apid=%d sid=0x%x 
> > per=0x%x irq=%d\n",
> >               __func__, apid, sid, per, id);
> >       writel_relaxed(irq_mask, pmic_arb->ver_ops->irq_clear(pmic_arb, 
> > apid));
> > -
> > -    if (pmic_arb_write_cmd(pmic_arb->spmic, SPMI_CMD_EXT_WRITEL, sid,
> > -            (per << 8) + QPNPINT_REG_LATCHED_CLR, &irq_mask, 1))
> > -        dev_err_ratelimited(&pmic_arb->spmic->dev, "failed to ack 
> > irq_mask = 0x%x for ppid = %x\n",
> > -                irq_mask, ppid);spmi: pmic-arb: cleanup unrequested 
> > irqs
> > -
> > -    if (pmic_arb_write_cmd(pmic_arb->spmic, SPMI_CMD_EXT_WRITEL, sid,
> > -                   (per << 8) + QPNPINT_REG_EN_CLR, &irq_mask, 1))
> > -        dev_err_ratelimited(&pmic_arb->spmic->dev, "failed to ack 
> > irq_mask = 0x%x for ppid = %x\n",
> > -                irq_mask, ppid);
> >   }
> >     static int periph_interrupt(struct spmi_pmic_arb *pmic_arb, u16 
> > apid)
> > @@ -674,6 +664,7 @@ static int qpnpint_irq_domain_activate(struct 
> > irq_domain *domain,
> >       u16 apid = hwirq_to_apid(d->hwirq);
> >       u16 sid = hwirq_to_sid(d->hwirq);
> >       u16 irq = hwirq_to_irq(d->hwirq);
> > +    u8 buf;
> >         if (pmic_arb->apid_data[apid].irq_ee != pmic_arb->ee) {
> >           dev_err(&pmic_arb->spmic->dev, "failed to xlate sid = %#x, 
> > periph = %#x, irq = %u: ee=%u but owner=%u\n",
> > @@ -682,6 +673,10 @@ static int qpnpint_irq_domain_activate(struct 
> > irq_domain *domain,
> >           return -ENODEV;
> >       }
> >   +    buf = BIT(irq);
> > +    qpnpint_spmi_write(d, QPNPINT_REG_EN_CLR, &buf, 1);
> > +    qpnpint_spmi_write(d, QPNPINT_REG_LATCHED_CLR, &buf, 1);
> > +
> >       return 0;
> >   }
>
> Shouldn't this have a
>
> Fixes: 6bc546e71e50 ("spmi: pmic-arb: cleanup unrequested irqs")
> Fixes: 02abec3616c1 ("spmi: pmic-arb: rename pa_xx to pmic_arb_xx and 
> other cleanup")
>
> so we know to backport as necessary
Got it, I will add the Fixes tag and send it again.

> ---
> bod