Re: [PATCH v4 06/14] spmi: pmic-arb: disassociate old virq if hwirq mapping already exists

From: Bjorn Andersson
Date: Mon Jan 14 2019 - 19:42:09 EST


On Sun 13 Jan 07:47 PST 2019, Brian Masney wrote:

> Check to see if the hwirq is already associated with another virq on
> this IRQ domain. If so, then disassociate it before associating the
> hwirq with the new virq.
>
> This is a temporary hack that is needed in order to not break git
> bisect for existing boards. The next patch in this series converts
> spmi-gpio to be a hierarchical IRQ chip, then there are several patches
> to update all of the device tree files, and finally this patch will be
> reverted within the same patch series.
>

You must maintain compatibility with existing DTB files (at least for
some time), so I don't think we can revert this patch at the end of the
series.

But the patch itself looks reasonable,

Acked-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

Regards,
Bjorn

> IRQs for spmi-gpio are all initially setup without an IRQ hierarchy
> on pmic-arb when mfd/qcom-spmi-pmic.c is probed (via the
> devm_of_platform_populate call) due to the interrupts property in
> device tree. Once spmi-gpio is converted to be a hierarchical IRQ chip
> in the next patch, existing users of gpio[d]_to_irq() will call
> pmic_gpio_to_irq(), and that will use the new IRQ chip code in
> spmi-gpio that sets up the IRQ in an IRQ hierarchy. The hwirq is now
> associated with two Linux virqs and interrupts will not work as
> expected. This patch corrects that issue.
>
> Driver was tested using gpio-keys and iadc/vadc on the LG Nexus 5
> (hammerhead) phone.
>
> Signed-off-by: Brian Masney <masneyb@xxxxxxxxxxxxx>
> ---
> This is a new patch introduced in V4, but this logic was present in V1.
>
> 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 356bc3f66e22..b7cfee831417 100644
> --- a/drivers/spmi/spmi-pmic-arb.c
> +++ b/drivers/spmi/spmi-pmic-arb.c
> @@ -744,8 +744,14 @@ static void qpnpint_irq_domain_map(struct spmi_pmic_arb *pmic_arb,
> struct irq_domain *domain, unsigned int virq,
> irq_hw_number_t hwirq)
> {
> + unsigned int old_virq;
> +
> dev_dbg(&pmic_arb->spmic->dev, "virq = %u, hwirq = %lu\n", virq, hwirq);
>
> + old_virq = irq_find_mapping(domain, hwirq);
> + if (old_virq)
> + irq_domain_disassociate(domain, old_virq);
> +
> irq_domain_set_info(domain, virq, hwirq, &pmic_arb_irqchip, pmic_arb,
> handle_level_irq, NULL, NULL);
> }
> --
> 2.17.2
>