Re: [PATCH 4/9] mfd: pm8xxx: disassociate old virq if hwirq mapping already exists

From: Lee Jones
Date: Wed Jan 30 2019 - 08:31:23 EST


Thomas,

On Fri, 25 Jan 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
> ssbi-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.
>
> IRQs for ssbi-gpio are all initially setup without an IRQ hierarchy
> this driver is probed due to the interrupts property in device tree.
> Once ssbi-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 ssbi-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.

I guess that's okay. Would quite like a second opinion though.

> This change was not tested on any actual hardware, however the same
> change was made to spmi-pmic-arb.c and tested on a LG Nexus 5
> (hammerhead) phone.
>
> Signed-off-by: Brian Masney <masneyb@xxxxxxxxxxxxx>
> ---
> drivers/mfd/qcom-pm8xxx.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/mfd/qcom-pm8xxx.c b/drivers/mfd/qcom-pm8xxx.c
> index a976890c4019..97b931465601 100644
> --- a/drivers/mfd/qcom-pm8xxx.c
> +++ b/drivers/mfd/qcom-pm8xxx.c
> @@ -387,6 +387,11 @@ static void pm8xxx_irq_domain_map(struct pm_irq_chip *chip,
> irq_hw_number_t hwirq, unsigned int type)
> {
> irq_flow_handler_t handler;
> + unsigned int old_virq;
> +
> + old_virq = irq_find_mapping(domain, hwirq);
> + if (old_virq)
> + irq_domain_disassociate(domain, old_virq);
>
> if (type & IRQ_TYPE_EDGE_BOTH)
> handler = handle_edge_irq;

--
Lee Jones [æçæ]
Linaro Services Technical Lead
Linaro.org â Open source software for ARM SoCs
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