[PATCH 12/17] ARM: OMAP2+: remove misuse of IRQF_NO_SUSPEND flag

[PATCH 12/17] ARM: OMAP2+: remove misuse of IRQF_NO_SUSPEND flag

[Sudeep Holla]

The IRQF_NO_SUSPEND flag is used to identify the interrupts that should
be left enabled so as to allow them to work as expected during the
suspend-resume cycle, but doesn't guarantee that it will wake the system
from a suspended state, enable_irq_wake is recommended to be used for
the wakeup.

This patch removes the use of IRQF_NO_SUSPEND flags replacing it with
enable_irq_wake instead.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: linux-omap@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 arch/arm/mach-omap2/mux.c    | 4 ++--
 arch/arm/mach-omap2/pm34xx.c | 9 ++++-----
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/arm/mach-omap2/mux.c b/arch/arm/mach-omap2/mux.c
index 176eef6ef338..12012bef8e63 100644
--- a/arch/arm/mach-omap2/mux.c
+++ b/arch/arm/mach-omap2/mux.c
@@ -810,13 +810,13 @@ int __init omap_mux_late_init(void)
 		return 0;
 
 	ret = request_irq(omap_prcm_event_to_irq("io"),
-		omap_hwmod_mux_handle_irq, IRQF_SHARED | IRQF_NO_SUSPEND,
+		omap_hwmod_mux_handle_irq, IRQF_SHARED,
 			"hwmod_io", omap_mux_late_init);
 
 	if (ret)
 		pr_warn("mux: Failed to setup hwmod io irq %d\n", ret);
 
-	return 0;
+	return enable_irq_wake(omap_prcm_event_to_irq("io"));
 }
 
 static void __init omap_mux_package_fixup(struct omap_mux *p,
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 87b98bf92366..4b7ac7cd633a 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -472,23 +472,22 @@ int __init omap3_pm_init(void)
 	prcm_setup_regs();
 
 	ret = request_irq(omap_prcm_event_to_irq("wkup"),
-		_prcm_int_handle_wakeup, IRQF_NO_SUSPEND, "pm_wkup", NULL);
+		_prcm_int_handle_wakeup, 0, "pm_wkup", NULL);
 
 	if (ret) {
 		pr_err("pm: Failed to request pm_wkup irq\n");
 		goto err1;
 	}
+	enable_irq_wake(omap_prcm_event_to_irq("wkup"));
 
 	/* IO interrupt is shared with mux code */
 	ret = request_irq(omap_prcm_event_to_irq("io"),
-		_prcm_int_handle_io, IRQF_SHARED | IRQF_NO_SUSPEND, "pm_io",
-		omap3_pm_init);
-	enable_irq(omap_prcm_event_to_irq("io"));
-
+		_prcm_int_handle_io, IRQF_SHARED, "pm_io", omap3_pm_init);
 	if (ret) {
 		pr_err("pm: Failed to request pm_io irq\n");
 		goto err2;
 	}
+	enable_irq_wake(omap_prcm_event_to_irq("io"));
 
 	ret = pwrdm_for_each(pwrdms_setup, NULL);
 	if (ret) {
-- 
1.9.1

Re: [PATCH 12/17] ARM: OMAP2+: remove misuse of IRQF_NO_SUSPEND flag

[Tony Lindgren]

* Sudeep Holla <sudeep.holla@arm.com> [150921 08:52]:
> The IRQF_NO_SUSPEND flag is used to identify the interrupts that should
> be left enabled so as to allow them to work as expected during the
> suspend-resume cycle, but doesn't guarantee that it will wake the system
> from a suspended state, enable_irq_wake is recommended to be used for
> the wakeup.
> 
> This patch removes the use of IRQF_NO_SUSPEND flags replacing it with
> enable_irq_wake instead.

Applying into omap-for-v4.4/cleanup thanks.

Tony

Re: [PATCH 12/17] ARM: OMAP2+: remove misuse of IRQF_NO_SUSPEND flag

[Tony Lindgren]

* Tony Lindgren <tony@atomide.com> [151012 13:27]:
> * Sudeep Holla <sudeep.holla@arm.com> [150921 08:52]:
> > The IRQF_NO_SUSPEND flag is used to identify the interrupts that should
> > be left enabled so as to allow them to work as expected during the
> > suspend-resume cycle, but doesn't guarantee that it will wake the system
> > from a suspended state, enable_irq_wake is recommended to be used for
> > the wakeup.
> > 
> > This patch removes the use of IRQF_NO_SUSPEND flags replacing it with
> > enable_irq_wake instead.
> 
> Applying into omap-for-v4.4/cleanup thanks.

Actually I don't think this does the right thing. The interrupts
in the $subject patch are in the always on powerdomain, and we really
want them to be excluded from the suspend.

So not applying without further explanations.

Regards,

Tony

Re: [PATCH 12/17] ARM: OMAP2+: remove misuse of IRQF_NO_SUSPEND flag

[Sudeep Holla]

On 12/10/15 21:28, Tony Lindgren wrote:
> * Tony Lindgren <tony@atomide.com> [151012 13:27]:
>> * Sudeep Holla <sudeep.holla@arm.com> [150921 08:52]:
>>> The IRQF_NO_SUSPEND flag is used to identify the interrupts that should
>>> be left enabled so as to allow them to work as expected during the
>>> suspend-resume cycle, but doesn't guarantee that it will wake the system
>>> from a suspended state, enable_irq_wake is recommended to be used for
>>> the wakeup.
>>>
>>> This patch removes the use of IRQF_NO_SUSPEND flags replacing it with
>>> enable_irq_wake instead.
>>
>> Applying into omap-for-v4.4/cleanup thanks.
>
> Actually I don't think this does the right thing. The interrupts
> in the $subject patch are in the always on powerdomain, and we really

Agreed

> want them to be excluded from the suspend.
>

OK but what's wrong with this patch. At-least the name suggest it's a
wakeup interrupt. And using IRQF_NO_SUSPEND for the wakeup interrupt is
simply wrong.

> So not applying without further explanations.
>

But I don't understand the real need for IRQF_NO_SUSPEND over wakeup APIs ?

-- 
Regards,
Sudeep

Re: [PATCH 12/17] ARM: OMAP2+: remove misuse of IRQF_NO_SUSPEND flag

[Tony Lindgren]

* Sudeep Holla <sudeep.holla@arm.com> [151013 03:46]:
> 
> 
> On 12/10/15 21:28, Tony Lindgren wrote:
> >* Tony Lindgren <tony@atomide.com> [151012 13:27]:
> >>* Sudeep Holla <sudeep.holla@arm.com> [150921 08:52]:
> >>>The IRQF_NO_SUSPEND flag is used to identify the interrupts that should
> >>>be left enabled so as to allow them to work as expected during the
> >>>suspend-resume cycle, but doesn't guarantee that it will wake the system
> >>>from a suspended state, enable_irq_wake is recommended to be used for
> >>>the wakeup.
> >>>
> >>>This patch removes the use of IRQF_NO_SUSPEND flags replacing it with
> >>>enable_irq_wake instead.
> >>
> >>Applying into omap-for-v4.4/cleanup thanks.
> >
> >Actually I don't think this does the right thing. The interrupts
> >in the $subject patch are in the always on powerdomain, and we really
> 
> Agreed
> 
> >want them to be excluded from the suspend.
> >
> 
> OK but what's wrong with this patch. At-least the name suggest it's a
> wakeup interrupt. And using IRQF_NO_SUSPEND for the wakeup interrupt is
> simply wrong.

Hmm so if we have a separate always on irq controller for the wake-up events
and we want to keep it always on and exclude it from any suspend related
things.. Why would we not use IRQF_NO_SUSPEND on it?

Above you say "The IRQF_NO_SUSPEND flag is used to identify the interrupts
that should be left enabled so as to allow them to work as expected during
the suspend-resume cycle..." and that's exactly what we want to do here :)

For the dedicated wake-up interrupts, we have separate registers to enable
and disable them. The $subject irq is the shared interrupt that allows
making use of the pin specific wake-up interrupts, and for those yes we
are using enable_irq_wake().

> >So not applying without further explanations.
> >
> 
> But I don't understand the real need for IRQF_NO_SUSPEND over wakeup APIs ?

Because in the $subject case we just want to always keep it on and
never suspend it. It's unrelated to the wakeup APIs at least for the
omap related SoCs.

Regards,

Tony

Re: [PATCH 12/17] ARM: OMAP2+: remove misuse of IRQF_NO_SUSPEND flag

[Sudeep Holla]

On 13/10/15 15:53, Tony Lindgren wrote:
> * Sudeep Holla <sudeep.holla@arm.com> [151013 03:46]:
>>
>>
>> On 12/10/15 21:28, Tony Lindgren wrote:
>>> * Tony Lindgren <tony@atomide.com> [151012 13:27]:
>>>> * Sudeep Holla <sudeep.holla@arm.com> [150921 08:52]:
>>>>> The IRQF_NO_SUSPEND flag is used to identify the interrupts that should
>>>>> be left enabled so as to allow them to work as expected during the
>>>>> suspend-resume cycle, but doesn't guarantee that it will wake the system
>>>> >from a suspended state, enable_irq_wake is recommended to be used for
>>>>> the wakeup.
>>>>>
>>>>> This patch removes the use of IRQF_NO_SUSPEND flags replacing it with
>>>>> enable_irq_wake instead.
>>>>
>>>> Applying into omap-for-v4.4/cleanup thanks.
>>>
>>> Actually I don't think this does the right thing. The interrupts
>>> in the $subject patch are in the always on powerdomain, and we really
>>
>> Agreed
>>
>>> want them to be excluded from the suspend.
>>>
>>
>> OK but what's wrong with this patch. At-least the name suggest it's a
>> wakeup interrupt. And using IRQF_NO_SUSPEND for the wakeup interrupt is
>> simply wrong.
>
> Hmm so if we have a separate always on irq controller for the wake-up events
> and we want to keep it always on and exclude it from any suspend related
> things.. Why would we not use IRQF_NO_SUSPEND on it?
>
> Above you say "The IRQF_NO_SUSPEND flag is used to identify the interrupts
> that should be left enabled so as to allow them to work as expected during
> the suspend-resume cycle..." and that's exactly what we want to do here :)
>

OK if these interrupts meet that criteria to use IRQF_NO_SUSPEND, then
it should be fine, my earlier argument was based on the assumption that
it's just another wakeup interrupt.

> For the dedicated wake-up interrupts, we have separate registers to enable
> and disable them. The $subject irq is the shared interrupt that allows
> making use of the pin specific wake-up interrupts, and for those yes we
> are using enable_irq_wake().
>

If it's already take care, then fine. I am just hunting all the misuse
of IRQF_NO_SUSPEND flag especially as wakeup source and fixing them

>>> So not applying without further explanations.
>>>
>>
>> But I don't understand the real need for IRQF_NO_SUSPEND over wakeup APIs ?
>
> Because in the $subject case we just want to always keep it on and
> never suspend it. It's unrelated to the wakeup APIs at least for the
> omap related SoCs.
>

OK, understood now. Thanks

--
Regards,
Sudeep