diff mbox series

[v1,1/3] power: domain: handle power supplies that need irq

Message ID 20220711094549.3445566-1-martin.kepplinger@puri.sm
State New
Headers show
Series [v1,1/3] power: domain: handle power supplies that need irq | expand

Commit Message

Martin Kepplinger July 11, 2022, 9:45 a.m. UTC
Handle a new DT property power-supply-needs-irq that boards can
use if the power-domains' power-supply node (regulator) needs
interrupts to function. An example is a pmic regulator on i2c.

Since suspend/resume doesn't work in these cases currently, switch
to the normal, outer suspend/resume callbacks.

Usually such a regulator already times out during suspend_noirq:

[   41.024193] buck4: failed to disable: -ETIMEDOUT

Initially systemd suspend problems had been discussed at
https://lore.kernel.org/linux-arm-kernel/20211002005954.1367653-8-l.stach@pengutronix.de/
which led to discussing the pmic that contains the regulators which
serve as power-domain power-supplies:
https://lore.kernel.org/linux-pm/573166b75e524517782471c2b7f96e03fd93d175.camel@puri.sm/T/

So this enables boards to use power-supply-needs-irq and fix systemd
suspend and resume.

Possibly one can find more changes this property should configure. They
can be added later when testing them.

Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
---
 drivers/base/power/domain.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

Comments

Martin Kepplinger July 11, 2022, 1:17 p.m. UTC | #1
Am Montag, dem 11.07.2022 um 12:38 +0200 schrieb Krzysztof Kozlowski:
> On 11/07/2022 11:45, Martin Kepplinger wrote:
> > Add the power-supply-needs-irq board description property for power
> > domains.
> 
> Where is a board description here? I think you just meant
> "power-supply-needs-irq property"?
> > 
> > Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
> > ---
> >  .../devicetree/bindings/power/power-domain.yaml        | 10
> > ++++++++++
> >  1 file changed, 10 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/power/power-
> > domain.yaml b/Documentation/devicetree/bindings/power/power-
> > domain.yaml
> > index 889091b9814f..e82c2f7ccb97 100644
> > --- a/Documentation/devicetree/bindings/power/power-domain.yaml
> > +++ b/Documentation/devicetree/bindings/power/power-domain.yaml
> > @@ -70,6 +70,16 @@ properties:
> >        by the given provider should be subdomains of the domain
> > specified
> >        by this binding.
> >  
> > +  power-supply: true
> 
> This is a new property not described in the commit msg.

true, I think it's missing and could be added as a separate patch.

> 
> > +
> > +  power-supply-needs-irq:
> > +    type: boolean
> > +    description:
> > +      A power-supply can link for example to a regulator
> > controlled via
> > +      i2c or otherwise needing interrupts enabled to be able to
> > enable and
> > +      disable. 
> 
> Not really a property of power domain. How the regulator supply works
> is
> entirely up to regulator. Otherwise such property should appear for
> every device.

you're right. The power-domain driver could read the power-supply
regulator node directly. Still, I think then a new regulator property
is needed instead, or is it?

> 
> > This property makes various callbacks usually run in the
> > +      noirq phase, being run when interrupts are available.
> 
> Last sentence does not fit - you embed Linux implementation into DT
> bindings. noirq phase is Linux specific.

oh I keep making this mistake. thanks for the fast review!

> 
> > +
> >  required:
> >    - "#power-domain-cells"
> >  
> 
> 
> Best regards,
> Krzysztof
Krzysztof Kozlowski July 12, 2022, 7:01 a.m. UTC | #2
On 11/07/2022 15:17, Martin Kepplinger wrote:
> Am Montag, dem 11.07.2022 um 12:38 +0200 schrieb Krzysztof Kozlowski:
>> On 11/07/2022 11:45, Martin Kepplinger wrote:
>>> Add the power-supply-needs-irq board description property for power
>>> domains.
>>
>> Where is a board description here? I think you just meant
>> "power-supply-needs-irq property"?
>>>
>>> Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
>>> ---
>>>  .../devicetree/bindings/power/power-domain.yaml        | 10
>>> ++++++++++
>>>  1 file changed, 10 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/power/power-
>>> domain.yaml b/Documentation/devicetree/bindings/power/power-
>>> domain.yaml
>>> index 889091b9814f..e82c2f7ccb97 100644
>>> --- a/Documentation/devicetree/bindings/power/power-domain.yaml
>>> +++ b/Documentation/devicetree/bindings/power/power-domain.yaml
>>> @@ -70,6 +70,16 @@ properties:
>>>        by the given provider should be subdomains of the domain
>>> specified
>>>        by this binding.
>>>  
>>> +  power-supply: true
>>
>> This is a new property not described in the commit msg.
> 
> true, I think it's missing and could be added as a separate patch.
> 
>>
>>> +
>>> +  power-supply-needs-irq:
>>> +    type: boolean
>>> +    description:
>>> +      A power-supply can link for example to a regulator
>>> controlled via
>>> +      i2c or otherwise needing interrupts enabled to be able to
>>> enable and
>>> +      disable. 
>>
>> Not really a property of power domain. How the regulator supply works
>> is
>> entirely up to regulator. Otherwise such property should appear for
>> every device.
> 
> you're right. The power-domain driver could read the power-supply
> regulator node directly. Still, I think then a new regulator property
> is needed instead, or is it?

In case of regulator, I am not so sure it needs a dedicated property of
DT. If it is I2C regulator - the parent node is I2C bus and regulator
device is some child of I2C controller (could be via a MFD device), so
no need for dedicated property.

If it uses interrupts, then:
1. The presence of interrupts is already known - "interrupts" property.
2. The actual use of interrupts is DT independent and only driver knows it.

Best regards,
Krzysztof
Martin Kepplinger July 12, 2022, 12:24 p.m. UTC | #3
Am Dienstag, dem 12.07.2022 um 09:01 +0200 schrieb Krzysztof Kozlowski:
> On 11/07/2022 15:17, Martin Kepplinger wrote:
> > Am Montag, dem 11.07.2022 um 12:38 +0200 schrieb Krzysztof
> > Kozlowski:
> > > On 11/07/2022 11:45, Martin Kepplinger wrote:
> > > > Add the power-supply-needs-irq board description property for
> > > > power
> > > > domains.
> > > 
> > > Where is a board description here? I think you just meant
> > > "power-supply-needs-irq property"?
> > > > 
> > > > Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
> > > > ---
> > > >  .../devicetree/bindings/power/power-domain.yaml        | 10
> > > > ++++++++++
> > > >  1 file changed, 10 insertions(+)
> > > > 
> > > > diff --git a/Documentation/devicetree/bindings/power/power-
> > > > domain.yaml b/Documentation/devicetree/bindings/power/power-
> > > > domain.yaml
> > > > index 889091b9814f..e82c2f7ccb97 100644
> > > > --- a/Documentation/devicetree/bindings/power/power-domain.yaml
> > > > +++ b/Documentation/devicetree/bindings/power/power-domain.yaml
> > > > @@ -70,6 +70,16 @@ properties:
> > > >        by the given provider should be subdomains of the domain
> > > > specified
> > > >        by this binding.
> > > >  
> > > > +  power-supply: true
> > > 
> > > This is a new property not described in the commit msg.
> > 
> > true, I think it's missing and could be added as a separate patch.
> > 
> > > 
> > > > +
> > > > +  power-supply-needs-irq:
> > > > +    type: boolean
> > > > +    description:
> > > > +      A power-supply can link for example to a regulator
> > > > controlled via
> > > > +      i2c or otherwise needing interrupts enabled to be able
> > > > to
> > > > enable and
> > > > +      disable. 
> > > 
> > > Not really a property of power domain. How the regulator supply
> > > works
> > > is
> > > entirely up to regulator. Otherwise such property should appear
> > > for
> > > every device.
> > 
> > you're right. The power-domain driver could read the power-supply
> > regulator node directly. Still, I think then a new regulator
> > property
> > is needed instead, or is it?
> 
> In case of regulator, I am not so sure it needs a dedicated property
> of
> DT. If it is I2C regulator - the parent node is I2C bus and regulator
> device is some child of I2C controller (could be via a MFD device),
> so
> no need for dedicated property.
> 
> If it uses interrupts, then:
> 1. The presence of interrupts is already known - "interrupts"
> property.
> 2. The actual use of interrupts is DT independent and only driver
> knows it.

thanks for this great suggestion! for the imx8mq devices this (1.)
indeed is the case for exactly the 3 regulators I manually describe
here. v2 of this patch looks very elegant (and I guess I could have
removed the DT people from the email, I forgot). here it is:

https://lore.kernel.org/linux-arm-kernel/20220712121832.3659769-1-martin.kepplinger@puri.sm/T/#u

> 
> Best regards,
> Krzysztof
diff mbox series

Patch

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 3e86772d5fac..c8fecba2c191 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2298,6 +2298,16 @@  static bool genpd_present(const struct generic_pm_domain *genpd)
 	return ret;
 }
 
+static void of_genpd_get_power_supply_irq(struct generic_pm_domain *pd)
+{
+	if (of_property_read_bool(pd->dev.of_node, "power-supply-needs-irq")) {
+		pd->domain.ops.suspend = genpd_suspend_noirq;
+		pd->domain.ops.resume = genpd_resume_noirq;
+		pd->domain.ops.suspend_noirq = NULL;
+		pd->domain.ops.resume_noirq = NULL;
+	}
+}
+
 /**
  * of_genpd_add_provider_simple() - Register a simple PM domain provider
  * @np: Device node pointer associated with the PM domain provider.
@@ -2343,6 +2353,8 @@  int of_genpd_add_provider_simple(struct device_node *np,
 	genpd->provider = &np->fwnode;
 	genpd->has_provider = true;
 
+	of_genpd_get_power_supply_irq(genpd);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
@@ -2394,6 +2406,8 @@  int of_genpd_add_provider_onecell(struct device_node *np,
 
 		genpd->provider = &np->fwnode;
 		genpd->has_provider = true;
+
+		of_genpd_get_power_supply_irq(genpd);
 	}
 
 	ret = genpd_add_provider(np, data->xlate, data);