On Thu, Mar 21 2019 at 15:54 -0600, Stephen Boyd wrote:
Quoting Marc Zyngier (2019-03-16 04:39:48)
On Fri, 15 Mar 2019 09:28:31 -0700
Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote:
> Quoting Lina Iyer (2019-03-13 14:18:41)
> > @@ -994,6 +1092,22 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl)
> > pctrl->irq_chip.irq_request_resources = msm_gpio_irq_reqres;
> > pctrl->irq_chip.irq_release_resources = msm_gpio_irq_relres;
> >
> > + chip->irq.chip = &pctrl->irq_chip;
> > + chip->irq.domain_ops = &msm_gpio_domain_ops;
> > + chip->irq.handler = handle_edge_irq;
> > + chip->irq.default_type = IRQ_TYPE_EDGE_RISING;
>
> This also changed from v3. It used to be IRQ_TYPE_NONE. Specifying this
> here seems to cause gpiolib to print a WARN.
>
>
> /*
> * Specifying a default trigger is a terrible idea if DT or ACPI is
> * used to configure the interrupts, as you may end up with
> * conflicting triggers. Tell the user, and reset to NONE.
> */
> if (WARN(np && type != IRQ_TYPE_NONE,
> "%s: Ignoring %u default trigger\n", np->full_name, type))
> type = IRQ_TYPE_NONE;
>
>
> So I guess this change should be dropped. Or at the least, it should be
> split out to it's own patch and the motivations can be discussed in the
> commit text.
It is something I requested (although I expected this to be a
different patch, and even a clarification would have been OK).
One way or another, the default trigger must match the flow handler. If
we set it up with IRQ_TYPE_NONE, what does it mean? The fact that
IRQ_TYPE_NONE acts as a wildcard doesn't mean the handle_edge_irq flow
handler is a good match for all interrupt types (it is rarely OK for
level interrupts).
I think this is a question for Thierry or Linus. I'm not sure why this
check was put in place in the code. I tried to dig into it really quick
but I didn't find anything obvious and then I gave up.
Maybe with hierarchical irqdomains we can drop this check? I don't think
the gpiolib core ever uses this 'default_type' or 'handler' for anything
once we replace the irqdomain that's used for a particular gpiochip with
a custom irqdomain. The only user I see, gpiochip_irq_map(), won't ever
be called so it really ends up being a thing that the driver specific
irqdomains should check for and reject when parsing the DT and it sees
IRQ_TYPE_NONE come out.
------8<-------
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 144af0733581..fe2f7888c473 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1922,7 +1922,7 @@ static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
* used to configure the interrupts, as you may end up with
* conflicting triggers. Tell the user, and reset to NONE.
*/
- if (WARN(np && type != IRQ_TYPE_NONE,
+ if (WARN(!gpiochip->irq.domain_ops && np && type != IRQ_TYPE_NONE,
"%s: Ignoring %u default trigger\n", np->full_name, type))
type = IRQ_TYPE_NONE;
Linus,
Any thoughts on this?
-- Lina
