Messages in this thread | | | Date | Tue, 19 May 2015 10:40:21 +0200 | Subject | Re: [PATCH v4 2/3] irqchip: GIC: Add support for irq_{get,set}_irqchip_state | From | Linus Walleij <> |
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On Thu, May 14, 2015 at 10:14 PM, Feng Kan <fkan@apm.com> wrote: > On Thu, May 14, 2015 at 3:32 AM, Linus Walleij <linus.walleij@linaro.org> wrote:
>> But surely the GPIO block has its own status register, so are >> you saying that this register is unreliable? > > When the GPIO is used as interrupt, the gpio block does not report the > status anymore. Which leaves us stuck with SPISR. >> >> I can think of a few reasons, like transient IRQs etc but >> what is actually causing this? > > I won't say the obvious.
Yeah I see your problem now :(
I think it's better to fix the access functions so that you can cross-call to the GIC driver to get the SPISR flag out though. Let's see what Marc says.
>> Which GPIO driver is this? Is it upstream? > > Yes, it is upstream. It is the xgene slimpro gpio driver. I am starting to > think that we ought to switch to use some gpio poll driver rather than > using gpio-key.
There is both gpio_keys_polled and IRQ-driven gpio_keys so yeah that's possible. But honestly I think it's better to deal with this problem for real because IRQ is more efficient.
So the way I perceive it this is the real problem:
+static int gic_irq_get_irqchip_state(struct irq_data *d, + enum irqchip_irq_state which, bool *val) +{ + switch (which) { (...) + case IRQCHIP_STATE_ACTIVE: + *val = gic_peek_irq(d, GIC_DIST_ACTIVE_SET); + break;
Here it reads the status from 0x300 where DIST_ACTIVE_SET is, so if you change GIC_DIST_ACTIVE_SET to 0xd04 (SPISR), does it start working?
I would *guess* that maybe you want to implement and ask for IRQCHIP_STATE_LINE_LEVEL instead of IRQCHIP_STATE_ACTIVE, and have that case: read from 0xd04 (SPISR) instead, because that makes more sense to me, or am I wrong at it?
+ case IRQCHIP_STATE_LINE_LEVEL: + *val = gic_peek_irq(d, GIC_DIST_SPISR); + break;
And then put a define into <linux/irqchip/arm-gic.h> for GIC_DIST_SPISR.
Yours, Linus Walleij
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