diff mbox

[RFC,1/3] PCI: rockchip: Add support for pcie wake irq

Message ID 20170816075224.31734-2-jeffy.chen@rock-chips.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jeffy Chen Aug. 16, 2017, 7:52 a.m. UTC
Add support for PCIE_WAKE pin in rockchip pcie driver.

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
---

 drivers/pci/host/pcie-rockchip.c | 58 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

Comments

Shawn Lin Aug. 16, 2017, 9 a.m. UTC | #1
Hi Jeffy,

On 2017/8/16 15:52, Jeffy Chen wrote:
> Add support for PCIE_WAKE pin in rockchip pcie driver.
> 
> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> ---
> 
>   drivers/pci/host/pcie-rockchip.c | 58 ++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 58 insertions(+)
> 
> diff --git a/drivers/pci/host/pcie-rockchip.c b/drivers/pci/host/pcie-rockchip.c
> index 7bb9870f6d8c..f969a6d3cd85 100644
> --- a/drivers/pci/host/pcie-rockchip.c
> +++ b/drivers/pci/host/pcie-rockchip.c
> @@ -38,6 +38,7 @@
>   #include <linux/platform_device.h>
>   #include <linux/reset.h>
>   #include <linux/regmap.h>
> +#include <linux/suspend.h>
>   
>   /*
>    * The upper 16 bits of PCIE_CLIENT_CONFIG are a write mask for the lower 16
> @@ -226,6 +227,8 @@ struct rockchip_pcie {
>   	struct	regulator *vpcie1v8; /* 1.8V power supply */
>   	struct	regulator *vpcie0v9; /* 0.9V power supply */
>   	struct	gpio_desc *ep_gpio;
> +	int	wake_irq;
> +	bool	wake_by_pcie;
>   	u32	lanes;
>   	u8	root_bus_nr;
>   	int	link_gen;
> @@ -853,6 +856,20 @@ static void rockchip_pcie_legacy_int_handler(struct irq_desc *desc)
>   	chained_irq_exit(chip, desc);
>   }
>   
> +static irqreturn_t rockchip_pcie_wake_irq_handler(int irq, void *arg)
> +{
> +	struct rockchip_pcie *rockchip = arg;
> +
> +	rockchip->wake_by_pcie = true;
> +
> +	disable_irq_nosync(rockchip->wake_irq);
> +	disable_irq_wake(rockchip->wake_irq);
> +
> +	pm_wakeup_event(rockchip->dev, 0);
> +	pm_system_wakeup();
> +
> +	return IRQ_HANDLED;
> +}
>   
>   /**
>    * rockchip_pcie_parse_dt - Parse Device Tree
> @@ -868,6 +885,7 @@ static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
>   	struct resource *regs;
>   	int irq;
>   	int err;
> +	bool wakeup = 0;
>   
>   	regs = platform_get_resource_byname(pdev,
>   					    IORESOURCE_MEM,
> @@ -1018,6 +1036,21 @@ static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
>   		return err;
>   	}
>   
> +	rockchip->wake_irq = platform_get_irq_byname(pdev, "wake");
> +	if (rockchip->wake_irq >= 0) {
> +		err = devm_request_irq(dev, rockchip->wake_irq,
> +				       rockchip_pcie_wake_irq_handler,
> +				       0, "pcie-wake", rockchip);
> +		if (err) {
> +			dev_err(dev, "failed to request PCIe wake IRQ\n");
> +			return err;

This is optional, so I'm not sure if we should prevent the driver to
probe?

> +		}
> +
> +		disable_irq(rockchip->wake_irq);
> +		wakeup = device_property_read_bool(dev, "wakeup-source");

The purpose we add this, is for ep to wakeup the system, so why not
always treate it as a wakeup source.

> +	}
> +	device_init_wakeup(dev, wakeup);
> +
>   	rockchip->vpcie3v3 = devm_regulator_get_optional(dev, "vpcie3v3");
>   	if (IS_ERR(rockchip->vpcie3v3)) {
>   		if (PTR_ERR(rockchip->vpcie3v3) == -EPROBE_DEFER)
> @@ -1270,6 +1303,30 @@ static int rockchip_pcie_wait_l2(struct rockchip_pcie *rockchip)
>   	return 0;
>   }
>   
> +static int __maybe_unused rockchip_pcie_suspend(struct device *dev)
> +{
> +	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
> +
> +	rockchip->wake_by_pcie = false;
> +
> +	if (device_may_wakeup(dev)) {
> +		enable_irq_wake(rockchip->wake_irq);
> +		enable_irq(rockchip->wake_irq);
> +	}
> +	return 0;
> +}
> +
> +static int __maybe_unused rockchip_pcie_resume(struct device *dev)
> +{
> +	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
> +
> +	if (device_may_wakeup(dev) && !rockchip->wake_by_pcie) {

I don't get this that why we need to check wake_by_pcie here?

> +		disable_irq(rockchip->wake_irq);
> +		disable_irq_wake(rockchip->wake_irq);
> +	}
> +	return 0;
> +}
> +
>   static int __maybe_unused rockchip_pcie_suspend_noirq(struct device *dev)
>   {
>   	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
> @@ -1548,6 +1605,7 @@ static int rockchip_pcie_remove(struct platform_device *pdev)
>   }
>   
>   static const struct dev_pm_ops rockchip_pcie_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend, rockchip_pcie_resume)
>   	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend_noirq,
>   				      rockchip_pcie_resume_noirq)
>   };
>
Brian Norris Aug. 16, 2017, 5:49 p.m. UTC | #2
Hi,

On Wed, Aug 16, 2017 at 03:52:22PM +0800, Jeffy Chen wrote:
> Add support for PCIE_WAKE pin in rockchip pcie driver.
> 
> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> ---
> 
>  drivers/pci/host/pcie-rockchip.c | 58 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 58 insertions(+)
> 
> diff --git a/drivers/pci/host/pcie-rockchip.c b/drivers/pci/host/pcie-rockchip.c
> index 7bb9870f6d8c..f969a6d3cd85 100644
> --- a/drivers/pci/host/pcie-rockchip.c
> +++ b/drivers/pci/host/pcie-rockchip.c
> @@ -38,6 +38,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/reset.h>
>  #include <linux/regmap.h>
> +#include <linux/suspend.h>
>  
>  /*
>   * The upper 16 bits of PCIE_CLIENT_CONFIG are a write mask for the lower 16
> @@ -226,6 +227,8 @@ struct rockchip_pcie {
>  	struct	regulator *vpcie1v8; /* 1.8V power supply */
>  	struct	regulator *vpcie0v9; /* 0.9V power supply */
>  	struct	gpio_desc *ep_gpio;
> +	int	wake_irq;
> +	bool	wake_by_pcie;
>  	u32	lanes;
>  	u8	root_bus_nr;
>  	int	link_gen;
> @@ -853,6 +856,20 @@ static void rockchip_pcie_legacy_int_handler(struct irq_desc *desc)
>  	chained_irq_exit(chip, desc);
>  }
>  
> +static irqreturn_t rockchip_pcie_wake_irq_handler(int irq, void *arg)
> +{
> +	struct rockchip_pcie *rockchip = arg;
> +
> +	rockchip->wake_by_pcie = true;
> +
> +	disable_irq_nosync(rockchip->wake_irq);
> +	disable_irq_wake(rockchip->wake_irq);
> +
> +	pm_wakeup_event(rockchip->dev, 0);
> +	pm_system_wakeup();
> +
> +	return IRQ_HANDLED;
> +}
>  
>  /**
>   * rockchip_pcie_parse_dt - Parse Device Tree
> @@ -868,6 +885,7 @@ static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
>  	struct resource *regs;
>  	int irq;
>  	int err;
> +	bool wakeup = 0;

'0' should be 'false'.

>  
>  	regs = platform_get_resource_byname(pdev,
>  					    IORESOURCE_MEM,
> @@ -1018,6 +1036,21 @@ static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
>  		return err;
>  	}
>  
> +	rockchip->wake_irq = platform_get_irq_byname(pdev, "wake");
> +	if (rockchip->wake_irq >= 0) {
> +		err = devm_request_irq(dev, rockchip->wake_irq,
> +				       rockchip_pcie_wake_irq_handler,
> +				       0, "pcie-wake", rockchip);
> +		if (err) {
> +			dev_err(dev, "failed to request PCIe wake IRQ\n");
> +			return err;
> +		}
> +
> +		disable_irq(rockchip->wake_irq);

If you're worried about keeping this disabled at first, you can just use
this nifty trick (since this isn't a shared interrupt) -- call this
before requesting the IRQ:

	irq_set_status_flags(rockchip->wake_irq, IRQ_NOAUTOEN);

You could also consider using dev_pm_set_dedicated_wake_irq() to handle
this -- but beware, it still might not quite handle level-triggered
interrupt properly. I'm pretty sure Tony Lindgren would be happy to get
testing or patches for that though :) He already sent me something a
while back but I didn't have time to test it out.

> +		wakeup = device_property_read_bool(dev, "wakeup-source");
> +	}
> +	device_init_wakeup(dev, wakeup);

Shouldn't you call 'device_init_wakeup(dev, false)' on remove()?

> +
>  	rockchip->vpcie3v3 = devm_regulator_get_optional(dev, "vpcie3v3");
>  	if (IS_ERR(rockchip->vpcie3v3)) {
>  		if (PTR_ERR(rockchip->vpcie3v3) == -EPROBE_DEFER)
> @@ -1270,6 +1303,30 @@ static int rockchip_pcie_wait_l2(struct rockchip_pcie *rockchip)
>  	return 0;
>  }
>  
> +static int __maybe_unused rockchip_pcie_suspend(struct device *dev)

Why do this in suspend() instead of suspend_noirq()? You shouldn't
really need a separate method here.

Note that this should be a level-triggered interrupt which remains
asserted, so there should be no chance of "missing" it if you don't
enable it in time.

And on a related note: if you try the dedicated wake irq approach, this
will only occur just before the noirq phase anyway, since
device_wakeup_arm_wake_irqs() is called in dpm_suspend_noirq().

> +{
> +	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
> +
> +	rockchip->wake_by_pcie = false;
> +
> +	if (device_may_wakeup(dev)) {
> +		enable_irq_wake(rockchip->wake_irq);
> +		enable_irq(rockchip->wake_irq);
> +	}
> +	return 0;
> +}
> +
> +static int __maybe_unused rockchip_pcie_resume(struct device *dev)
> +{
> +	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
> +
> +	if (device_may_wakeup(dev) && !rockchip->wake_by_pcie) {

The use of 'wake_by_pcie' is racy; an interrupt could be in flight (but
not completed), and so it could set 'wake_by_pcie' just after you're
reading this. Then, you'll get a double-disable.

I believe the safe way to handle this would be to use an atomic
test-and-set / test-and-clear approach (either atomic_cmpxchg(), or use
a spinlock).

> +		disable_irq(rockchip->wake_irq);
> +		disable_irq_wake(rockchip->wake_irq);
> +	}
> +	return 0;
> +}
> +
>  static int __maybe_unused rockchip_pcie_suspend_noirq(struct device *dev)
>  {
>  	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
> @@ -1548,6 +1605,7 @@ static int rockchip_pcie_remove(struct platform_device *pdev)
>  }
>  
>  static const struct dev_pm_ops rockchip_pcie_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend, rockchip_pcie_resume)
>  	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend_noirq,
>  				      rockchip_pcie_resume_noirq)
>  };

Brian
Jeffy Chen Aug. 17, 2017, 12:25 a.m. UTC | #3
hi shawn,


On 08/16/2017 05:00 PM, Shawn Lin wrote:
> Hi Jeffy,
>
> On 2017/8/16 15:52, Jeffy Chen wrote:
>> Add support for PCIE_WAKE pin in rockchip pcie driver.
>>
>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>> ---
>>
>>   drivers/pci/host/pcie-rockchip.c | 58
>> ++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 58 insertions(+)
>>
>> diff --git a/drivers/pci/host/pcie-rockchip.c
>> b/drivers/pci/host/pcie-rockchip.c
>> index 7bb9870f6d8c..f969a6d3cd85 100644
>> --- a/drivers/pci/host/pcie-rockchip.c
>> +++ b/drivers/pci/host/pcie-rockchip.c
>> @@ -38,6 +38,7 @@
>>   #include <linux/platform_device.h>
>>   #include <linux/reset.h>
>>   #include <linux/regmap.h>
>> +#include <linux/suspend.h>
>>   /*
>>    * The upper 16 bits of PCIE_CLIENT_CONFIG are a write mask for the
>> lower 16
>> @@ -226,6 +227,8 @@ struct rockchip_pcie {
>>       struct    regulator *vpcie1v8; /* 1.8V power supply */
>>       struct    regulator *vpcie0v9; /* 0.9V power supply */
>>       struct    gpio_desc *ep_gpio;
>> +    int    wake_irq;
>> +    bool    wake_by_pcie;
>>       u32    lanes;
>>       u8    root_bus_nr;
>>       int    link_gen;
>> @@ -853,6 +856,20 @@ static void
>> rockchip_pcie_legacy_int_handler(struct irq_desc *desc)
>>       chained_irq_exit(chip, desc);
>>   }
>> +static irqreturn_t rockchip_pcie_wake_irq_handler(int irq, void *arg)
>> +{
>> +    struct rockchip_pcie *rockchip = arg;
>> +
>> +    rockchip->wake_by_pcie = true;
>> +
>> +    disable_irq_nosync(rockchip->wake_irq);
>> +    disable_irq_wake(rockchip->wake_irq);
>> +
>> +    pm_wakeup_event(rockchip->dev, 0);
>> +    pm_system_wakeup();
>> +
>> +    return IRQ_HANDLED;
>> +}
>>   /**
>>    * rockchip_pcie_parse_dt - Parse Device Tree
>> @@ -868,6 +885,7 @@ static int rockchip_pcie_parse_dt(struct
>> rockchip_pcie *rockchip)
>>       struct resource *regs;
>>       int irq;
>>       int err;
>> +    bool wakeup = 0;
>>       regs = platform_get_resource_byname(pdev,
>>                           IORESOURCE_MEM,
>> @@ -1018,6 +1036,21 @@ static int rockchip_pcie_parse_dt(struct
>> rockchip_pcie *rockchip)
>>           return err;
>>       }
>> +    rockchip->wake_irq = platform_get_irq_byname(pdev, "wake");
>> +    if (rockchip->wake_irq >= 0) {
>> +        err = devm_request_irq(dev, rockchip->wake_irq,
>> +                       rockchip_pcie_wake_irq_handler,
>> +                       0, "pcie-wake", rockchip);
>> +        if (err) {
>> +            dev_err(dev, "failed to request PCIe wake IRQ\n");
>> +            return err;
>
> This is optional, so I'm not sure if we should prevent the driver to
> probe?
it would only break probe when there's a wake irq, but failed to enable 
it. but the wake irq itself is optional
>
>> +        }
>> +
>> +        disable_irq(rockchip->wake_irq);
>> +        wakeup = device_property_read_bool(dev, "wakeup-source");
>
> The purpose we add this, is for ep to wakeup the system, so why not
> always treate it as a wakeup source.
it's an extra option to disable wake by wakeup-source property
>
>> +    }
>> +    device_init_wakeup(dev, wakeup);
>> +
>>       rockchip->vpcie3v3 = devm_regulator_get_optional(dev, "vpcie3v3");
>>       if (IS_ERR(rockchip->vpcie3v3)) {
>>           if (PTR_ERR(rockchip->vpcie3v3) == -EPROBE_DEFER)
>> @@ -1270,6 +1303,30 @@ static int rockchip_pcie_wait_l2(struct
>> rockchip_pcie *rockchip)
>>       return 0;
>>   }
>> +static int __maybe_unused rockchip_pcie_suspend(struct device *dev)
>> +{
>> +    struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
>> +
>> +    rockchip->wake_by_pcie = false;
>> +
>> +    if (device_may_wakeup(dev)) {
>> +        enable_irq_wake(rockchip->wake_irq);
>> +        enable_irq(rockchip->wake_irq);
>> +    }
>> +    return 0;
>> +}
>> +
>> +static int __maybe_unused rockchip_pcie_resume(struct device *dev)
>> +{
>> +    struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
>> +
>> +    if (device_may_wakeup(dev) && !rockchip->wake_by_pcie) {
>
> I don't get this that why we need to check wake_by_pcie here?
>
it's to avoid double disable when it got a irq before resume
>> +        disable_irq(rockchip->wake_irq);
>> +        disable_irq_wake(rockchip->wake_irq);
>> +    }
>> +    return 0;
>> +}
>> +
>>   static int __maybe_unused rockchip_pcie_suspend_noirq(struct device
>> *dev)
>>   {
>>       struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
>> @@ -1548,6 +1605,7 @@ static int rockchip_pcie_remove(struct
>> platform_device *pdev)
>>   }
>>   static const struct dev_pm_ops rockchip_pcie_pm_ops = {
>> +    SET_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend, rockchip_pcie_resume)
>>       SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend_noirq,
>>                         rockchip_pcie_resume_noirq)
>>   };
>>
>
>
>
Jeffy Chen Aug. 17, 2017, 12:03 p.m. UTC | #4
Hi Brian,

i've tried dev_pm_set_dedicated_wake_irq, it doesn't work well on 
upstream kernel(for level irq).


it looks like we would delay real set trigger type to request irq after 
this commit:
1e2a7d78499e irqdomain: Don't set type when mapping an IRQ

so calling irq_set_status_flags before request irq would lose trigger 
type setting.


things work well after reverted that commit, so i will send my patch 
soon, and ask irq people about it :)


On 08/17/2017 01:49 AM, Brian Norris wrote:
>  Hi,
>
> On Wed, Aug 16, 2017 at 03:52:22PM +0800, Jeffy Chen wrote:
>> Add support for PCIE_WAKE pin in rockchip pcie driver.
>>
>> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
>> ---
>>
>>   drivers/pci/host/pcie-rockchip.c | 58 ++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 58 insertions(+)
>>
>> diff --git a/drivers/pci/host/pcie-rockchip.c b/drivers/pci/host/pcie-rockchip.c
>> index 7bb9870f6d8c..f969a6d3cd85 100644
>> --- a/drivers/pci/host/pcie-rockchip.c
>> +++ b/drivers/pci/host/pcie-rockchip.c
>> @@ -38,6 +38,7 @@
>>   #include <linux/platform_device.h>
>>   #include <linux/reset.h>
>>   #include <linux/regmap.h>
>> +#include <linux/suspend.h>
>>
>>   /*
>>    * The upper 16 bits of PCIE_CLIENT_CONFIG are a write mask for the lower 16
>> @@ -226,6 +227,8 @@ struct rockchip_pcie {
>>   	struct	regulator *vpcie1v8; /* 1.8V power supply */
>>   	struct	regulator *vpcie0v9; /* 0.9V power supply */
>>   	struct	gpio_desc *ep_gpio;
>> +	int	wake_irq;
>> +	bool	wake_by_pcie;
>>   	u32	lanes;
>>   	u8	root_bus_nr;
>>   	int	link_gen;
>> @@ -853,6 +856,20 @@ static void rockchip_pcie_legacy_int_handler(struct irq_desc *desc)
>>   	chained_irq_exit(chip, desc);
>>   }
>>
>> +static irqreturn_t rockchip_pcie_wake_irq_handler(int irq, void *arg)
>> +{
>> +	struct rockchip_pcie *rockchip = arg;
>> +
>> +	rockchip->wake_by_pcie = true;
>> +
>> +	disable_irq_nosync(rockchip->wake_irq);
>> +	disable_irq_wake(rockchip->wake_irq);
>> +
>> +	pm_wakeup_event(rockchip->dev, 0);
>> +	pm_system_wakeup();
>> +
>> +	return IRQ_HANDLED;
>> +}
>>
>>   /**
>>    * rockchip_pcie_parse_dt - Parse Device Tree
>> @@ -868,6 +885,7 @@ static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
>>   	struct resource *regs;
>>   	int irq;
>>   	int err;
>> +	bool wakeup = 0;
>
> '0' should be 'false'.
right
>
>>
>>   	regs = platform_get_resource_byname(pdev,
>>   					    IORESOURCE_MEM,
>> @@ -1018,6 +1036,21 @@ static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
>>   		return err;
>>   	}
>>
>> +	rockchip->wake_irq = platform_get_irq_byname(pdev, "wake");
>> +	if (rockchip->wake_irq >= 0) {
>> +		err = devm_request_irq(dev, rockchip->wake_irq,
>> +				       rockchip_pcie_wake_irq_handler,
>> +				       0, "pcie-wake", rockchip);
>> +		if (err) {
>> +			dev_err(dev, "failed to request PCIe wake IRQ\n");
>> +			return err;
>> +		}
>> +
>> +		disable_irq(rockchip->wake_irq);
>
> If you're worried about keeping this disabled at first, you can just use
> this nifty trick (since this isn't a shared interrupt) -- call this
> before requesting the IRQ:
>
> 	irq_set_status_flags(rockchip->wake_irq, IRQ_NOAUTOEN);
>
> You could also consider using dev_pm_set_dedicated_wake_irq() to handle
> this -- but beware, it still might not quite handle level-triggered
> interrupt properly. I'm pretty sure Tony Lindgren would be happy to get
> testing or patches for that though :) He already sent me something a
> while back but I didn't have time to test it out.
ok, that seems very handy
>
>> +		wakeup = device_property_read_bool(dev, "wakeup-source");
>> +	}
>> +	device_init_wakeup(dev, wakeup);
>
> Shouldn't you call 'device_init_wakeup(dev, false)' on remove()?
ok
>
>> +
>>   	rockchip->vpcie3v3 = devm_regulator_get_optional(dev, "vpcie3v3");
>>   	if (IS_ERR(rockchip->vpcie3v3)) {
>>   		if (PTR_ERR(rockchip->vpcie3v3) == -EPROBE_DEFER)
>> @@ -1270,6 +1303,30 @@ static int rockchip_pcie_wait_l2(struct rockchip_pcie *rockchip)
>>   	return 0;
>>   }
>>
>> +static int __maybe_unused rockchip_pcie_suspend(struct device *dev)
>
> Why do this in suspend() instead of suspend_noirq()? You shouldn't
> really need a separate method here.
>
> Note that this should be a level-triggered interrupt which remains
> asserted, so there should be no chance of "missing" it if you don't
> enable it in time.
>
> And on a related note: if you try the dedicated wake irq approach, this
> will only occur just before the noirq phase anyway, since
> device_wakeup_arm_wake_irqs() is called in dpm_suspend_noirq().
right
>
>> +{
>> +	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
>> +
>> +	rockchip->wake_by_pcie = false;
>> +
>> +	if (device_may_wakeup(dev)) {
>> +		enable_irq_wake(rockchip->wake_irq);
>> +		enable_irq(rockchip->wake_irq);
>> +	}
>> +	return 0;
>> +}
>> +
>> +static int __maybe_unused rockchip_pcie_resume(struct device *dev)
>> +{
>> +	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
>> +
>> +	if (device_may_wakeup(dev) && !rockchip->wake_by_pcie) {
>
> The use of 'wake_by_pcie' is racy; an interrupt could be in flight (but
> not completed), and so it could set 'wake_by_pcie' just after you're
> reading this. Then, you'll get a double-disable.
>
> I believe the safe way to handle this would be to use an atomic
> test-and-set / test-and-clear approach (either atomic_cmpxchg(), or use
> a spinlock).
right, and we don't need these if using dev_pm_set_dedicated_wake_irq
>
>> +		disable_irq(rockchip->wake_irq);
>> +		disable_irq_wake(rockchip->wake_irq);
>> +	}
>> +	return 0;
>> +}
>> +
>>   static int __maybe_unused rockchip_pcie_suspend_noirq(struct device *dev)
>>   {
>>   	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
>> @@ -1548,6 +1605,7 @@ static int rockchip_pcie_remove(struct platform_device *pdev)
>>   }
>>
>>   static const struct dev_pm_ops rockchip_pcie_pm_ops = {
>> +	SET_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend, rockchip_pcie_resume)
>>   	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend_noirq,
>>   				      rockchip_pcie_resume_noirq)
>>   };
>
> Brian
>
>
>
diff mbox

Patch

diff --git a/drivers/pci/host/pcie-rockchip.c b/drivers/pci/host/pcie-rockchip.c
index 7bb9870f6d8c..f969a6d3cd85 100644
--- a/drivers/pci/host/pcie-rockchip.c
+++ b/drivers/pci/host/pcie-rockchip.c
@@ -38,6 +38,7 @@ 
 #include <linux/platform_device.h>
 #include <linux/reset.h>
 #include <linux/regmap.h>
+#include <linux/suspend.h>
 
 /*
  * The upper 16 bits of PCIE_CLIENT_CONFIG are a write mask for the lower 16
@@ -226,6 +227,8 @@  struct rockchip_pcie {
 	struct	regulator *vpcie1v8; /* 1.8V power supply */
 	struct	regulator *vpcie0v9; /* 0.9V power supply */
 	struct	gpio_desc *ep_gpio;
+	int	wake_irq;
+	bool	wake_by_pcie;
 	u32	lanes;
 	u8	root_bus_nr;
 	int	link_gen;
@@ -853,6 +856,20 @@  static void rockchip_pcie_legacy_int_handler(struct irq_desc *desc)
 	chained_irq_exit(chip, desc);
 }
 
+static irqreturn_t rockchip_pcie_wake_irq_handler(int irq, void *arg)
+{
+	struct rockchip_pcie *rockchip = arg;
+
+	rockchip->wake_by_pcie = true;
+
+	disable_irq_nosync(rockchip->wake_irq);
+	disable_irq_wake(rockchip->wake_irq);
+
+	pm_wakeup_event(rockchip->dev, 0);
+	pm_system_wakeup();
+
+	return IRQ_HANDLED;
+}
 
 /**
  * rockchip_pcie_parse_dt - Parse Device Tree
@@ -868,6 +885,7 @@  static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
 	struct resource *regs;
 	int irq;
 	int err;
+	bool wakeup = 0;
 
 	regs = platform_get_resource_byname(pdev,
 					    IORESOURCE_MEM,
@@ -1018,6 +1036,21 @@  static int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
 		return err;
 	}
 
+	rockchip->wake_irq = platform_get_irq_byname(pdev, "wake");
+	if (rockchip->wake_irq >= 0) {
+		err = devm_request_irq(dev, rockchip->wake_irq,
+				       rockchip_pcie_wake_irq_handler,
+				       0, "pcie-wake", rockchip);
+		if (err) {
+			dev_err(dev, "failed to request PCIe wake IRQ\n");
+			return err;
+		}
+
+		disable_irq(rockchip->wake_irq);
+		wakeup = device_property_read_bool(dev, "wakeup-source");
+	}
+	device_init_wakeup(dev, wakeup);
+
 	rockchip->vpcie3v3 = devm_regulator_get_optional(dev, "vpcie3v3");
 	if (IS_ERR(rockchip->vpcie3v3)) {
 		if (PTR_ERR(rockchip->vpcie3v3) == -EPROBE_DEFER)
@@ -1270,6 +1303,30 @@  static int rockchip_pcie_wait_l2(struct rockchip_pcie *rockchip)
 	return 0;
 }
 
+static int __maybe_unused rockchip_pcie_suspend(struct device *dev)
+{
+	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
+
+	rockchip->wake_by_pcie = false;
+
+	if (device_may_wakeup(dev)) {
+		enable_irq_wake(rockchip->wake_irq);
+		enable_irq(rockchip->wake_irq);
+	}
+	return 0;
+}
+
+static int __maybe_unused rockchip_pcie_resume(struct device *dev)
+{
+	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev) && !rockchip->wake_by_pcie) {
+		disable_irq(rockchip->wake_irq);
+		disable_irq_wake(rockchip->wake_irq);
+	}
+	return 0;
+}
+
 static int __maybe_unused rockchip_pcie_suspend_noirq(struct device *dev)
 {
 	struct rockchip_pcie *rockchip = dev_get_drvdata(dev);
@@ -1548,6 +1605,7 @@  static int rockchip_pcie_remove(struct platform_device *pdev)
 }
 
 static const struct dev_pm_ops rockchip_pcie_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend, rockchip_pcie_resume)
 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(rockchip_pcie_suspend_noirq,
 				      rockchip_pcie_resume_noirq)
 };