Re: [PATCH] irqchip/irq-mst: Support polarity configuration

Mark-PK Tsai
2021-03-08T03:02:33Z

From: Marc Zyngier <maz@kernel.org>

> >
> > Support irq polarity configuration and save and restore the config
> > when system suspend and resume.
> >
> > Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> > ---
> > drivers/irqchip/irq-mst-intc.c | 87 ++++++++++++++++++++++++++++++++--
> > 1 file changed, 84 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/irqchip/irq-mst-intc.c b/drivers/irqchip/irq-mst-intc.c
> > index 143657b0cf28..979a4d55bcb1 100644
> > --- a/drivers/irqchip/irq-mst-intc.c
> > +++ b/drivers/irqchip/irq-mst-intc.c
> > @@ -13,15 +13,25 @@
> > #include <linux/of_irq.h>
> > #include <linux/slab.h>
> > #include <linux/spinlock.h>
> > +#include <linux/syscore_ops.h>
> >
> > -#define INTC_MASK 0x0
> > -#define INTC_EOI 0x20
> > +#define INTC_MASK 0x0
> > +#define INTC_REV_POLARITY 0x10
> > +#define INTC_EOI 0x20
> > +
> > +#ifdef CONFIG_PM_SLEEP
> > +static LIST_HEAD(mst_intc_list);
> > +#endif
> >
> > struct mst_intc_chip_data {
> > raw_spinlock_t lock;
> > unsigned int irq_start, nr_irqs;
> > void __iomem *base;
> > bool no_eoi;
> > +#ifdef CONFIG_PM_SLEEP
> > + struct list_head entry;
> > + u16 saved_polarity_conf[DIV_ROUND_UP(64, 16)];
>
> Where is this 64 coming from?

The maximum number of interrupts a mst-intc supports is 64 in
Mstar and Mediatek SoCs now.
So I just use the maximum number of interrupts here.

>
> > +#endif
> > };
> >
> > static void mst_set_irq(struct irq_data *d, u32 offset)
> > @@ -78,6 +88,16 @@ static void mst_intc_eoi_irq(struct irq_data *d)
> > irq_chip_eoi_parent(d);
> > }
> >
> > +static int mst_irq_chip_set_type(struct irq_data *data, unsigned int type)
> > +{
> > + if (type == IRQ_TYPE_LEVEL_LOW) {
> > + mst_set_irq(data, INTC_REV_POLARITY);
> > + type = IRQ_TYPE_LEVEL_HIGH;
> > + }
>
> If you are introducing a irq_set_type callback, you need to return an
> error for the settings you don't handle.

Got it, thanks for the comment.
I will add it in the next patch.