diff mbox

[v2] extcon: usb-gpio: Don't miss event during suspend/resume

Message ID 57075F23.8080703@ti.com
State New
Headers show

Commit Message

Roger Quadros April 8, 2016, 7:34 a.m. UTC
Pin state might have changed during suspend/resume while
our interrupts were disabled and if device doesn't support wakeup.

Scan for change during resume for such case.

Signed-off-by: Roger Quadros <rogerq@ti.com>

---
v2:
- only check for state change during resume if device wakeup is not supported

 drivers/extcon/extcon-usb-gpio.c | 2 ++
 1 file changed, 2 insertions(+)

-- 
2.5.0

Comments

Roger Quadros April 11, 2016, 11:39 a.m. UTC | #1
Chanwoo,

On 11/04/16 14:12, Chanwoo Choi wrote:
> On 2016년 04월 11일 17:37, Grygorii Strashko wrote:

>> On 04/11/2016 03:31 AM, Chanwoo Choi wrote:

>>> Hi Roger,

>>>

>>> On 2016년 04월 08일 16:34, Roger Quadros wrote:

>>>> Pin state might have changed during suspend/resume while

>>>> our interrupts were disabled and if device doesn't support wakeup.

>>>>

>>>> Scan for change during resume for such case.

>>>>

>>>> Signed-off-by: Roger Quadros <rogerq@ti.com>

>>>> ---

>>>> v2:

>>>> - only check for state change during resume if device wakeup is not supported

>>>>

>>>>   drivers/extcon/extcon-usb-gpio.c | 2 ++

>>>>   1 file changed, 2 insertions(+)

>>>>

>>>> diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c

>>>> index bc61d11..118f8ab 100644

>>>> --- a/drivers/extcon/extcon-usb-gpio.c

>>>> +++ b/drivers/extcon/extcon-usb-gpio.c

>>>> @@ -185,6 +185,8 @@ static int usb_extcon_resume(struct device *dev)

>>>>   	int ret = 0;

>>>>   

>>>>   	enable_irq(info->id_irq);

>>>> +	if (!device_may_wakeup(dev))

>>>> +		usb_extcon_detect_cable(&info->wq_detcable.work);

>>>

>>> The device_may_wakeup() check the following two states:

>>> - dev->power.can_wakeup - device_init_wakeup() function set the this field.

>>> - dev->power.wakeup - device_wakeup_enable() function set the this field.

>>>

>>> The probe function of extcon-usb-gpio.c always call the 'device_init_wakeup(dev,true).

>>> But, anywhere in extcon-usb-gpio.c don't handle the device_wakeup_enable() for dev->power.wakeup.

>>

>>

>> device_init_wakeup()

>>  |-> device_wakeup_enable()

>>

>>>

>>> In the extcon-usb-gpio.c, device_may_wakeup(dev) return always 'false'.

>>> If you use the only device_may_wakeup(),

>>> device_may_wakeup() is not able to check whether interrupt is wakeup source or not.

>>>

>>

>> This check is correct and it also will take into account wake up settings changes

>> which can be made through sysfs: /sys/.../devX/power/wakeup

>>

> 

> To Grygorii,

> 

> You're right. I was mistaken. Again, I analyzed the sequence about wakeup.

> Thanks for your reply.

> 

> 1. Register device as wakeup_source.

>  device_init_wakeup(dev, true) on probe()

> 	device_wakeup_enable(dev)

> 		device_source_register(const char *name)

> 			struct wakeup_source *ws;

> 			ws = wakeup_source_create(name)

> 			if (ws)

> 				wakeup_source_add(ws);

> 					...

> 					list_add_rcu(&ws->entry, &wakeup_sources);

> 					...

> 			return ws;

> 			

> 			

> 2. Register the interrupt as wake_irq

> dev_pm_set_wake_irq(struct device *dev, int irq) on probe()

> 	struct wake_irq *wirq;

> 	wirq->dev = dev;

> 	wirq->irq = irq;

> 	dev_pm_attach_wake_irq(dev, irq, wirq);

> 		device_wakeup_attach_irq(*dev, *wakeirq)

> 			struct wakeup_source *ws;

> 			ws = dev->power.wakeup;

> 			ws->wakeirq = wakeirq;

> 

> 

> 3. Enable irq wake if device is already registed to wakeup_sources.

> dpm_suspend_noirq()

> 	device_wakeup_arm_wake_irqs()

> 		list_for_each_entry_rcu(ws, &wakeup_sources, entry) {

> 			if (ws->wakeirq)

> 				dev_pm_arm_wake_irq(sw->wakeirq);

> 					if (device_may_wakeup(wirq->dev))

> 						enable_irq_wake(wirq->irq);

> 

> 

> To Roger,

> 

> How about using the queue_delayed_work() instead of direct call function?

> Because the spent time of wakeup from suspend state should be fast.

> So, I think that you better to use the queue_delayed_work().

> 

> diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c

> index 118f8ab3be73..f6cbdfe31519 100644

> --- a/drivers/extcon/extcon-usb-gpio.c

> +++ b/drivers/extcon/extcon-usb-gpio.c

> @@ -186,7 +186,9 @@ static int usb_extcon_resume(struct device *dev)

>  

>         enable_irq(info->id_irq);

>         if (!device_may_wakeup(dev))

> -               usb_extcon_detect_cable(&info->wq_detcable.work);

> +               queue_delayed_work(system_power_efficient_wq,

> +                               &info->wq_detcable,

> +                               info->debounce_jiffies);


Why not to just use queue_work() instead of queue_delayed_work()
as don't need to debounce the input?

cheers,
-roger

>  

>         return ret;

>  }
Roger Quadros April 11, 2016, 2:02 p.m. UTC | #2
On 11/04/16 16:17, Chanwoo Choi wrote:
> Hi Roger,

> 

> On Mon, Apr 11, 2016 at 8:39 PM, Roger Quadros <rogerq@ti.com> wrote:

>> Chanwoo,

>>

>> On 11/04/16 14:12, Chanwoo Choi wrote:

>>> On 2016년 04월 11일 17:37, Grygorii Strashko wrote:

>>>> On 04/11/2016 03:31 AM, Chanwoo Choi wrote:

>>>>> Hi Roger,

>>>>>

>>>>> On 2016년 04월 08일 16:34, Roger Quadros wrote:

>>>>>> Pin state might have changed during suspend/resume while

>>>>>> our interrupts were disabled and if device doesn't support wakeup.

>>>>>>

>>>>>> Scan for change during resume for such case.

>>>>>>

>>>>>> Signed-off-by: Roger Quadros <rogerq@ti.com>

>>>>>> ---

>>>>>> v2:

>>>>>> - only check for state change during resume if device wakeup is not supported

>>>>>>

>>>>>>   drivers/extcon/extcon-usb-gpio.c | 2 ++

>>>>>>   1 file changed, 2 insertions(+)

>>>>>>

>>>>>> diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c

>>>>>> index bc61d11..118f8ab 100644

>>>>>> --- a/drivers/extcon/extcon-usb-gpio.c

>>>>>> +++ b/drivers/extcon/extcon-usb-gpio.c

>>>>>> @@ -185,6 +185,8 @@ static int usb_extcon_resume(struct device *dev)

>>>>>>    int ret = 0;

>>>>>>

>>>>>>    enable_irq(info->id_irq);

>>>>>> +  if (!device_may_wakeup(dev))

>>>>>> +          usb_extcon_detect_cable(&info->wq_detcable.work);

>>>>>

>>>>> The device_may_wakeup() check the following two states:

>>>>> - dev->power.can_wakeup - device_init_wakeup() function set the this field.

>>>>> - dev->power.wakeup - device_wakeup_enable() function set the this field.

>>>>>

>>>>> The probe function of extcon-usb-gpio.c always call the 'device_init_wakeup(dev,true).

>>>>> But, anywhere in extcon-usb-gpio.c don't handle the device_wakeup_enable() for dev->power.wakeup.

>>>>

>>>>

>>>> device_init_wakeup()

>>>>  |-> device_wakeup_enable()

>>>>

>>>>>

>>>>> In the extcon-usb-gpio.c, device_may_wakeup(dev) return always 'false'.

>>>>> If you use the only device_may_wakeup(),

>>>>> device_may_wakeup() is not able to check whether interrupt is wakeup source or not.

>>>>>

>>>>

>>>> This check is correct and it also will take into account wake up settings changes

>>>> which can be made through sysfs: /sys/.../devX/power/wakeup

>>>>

>>>

>>> To Grygorii,

>>>

>>> You're right. I was mistaken. Again, I analyzed the sequence about wakeup.

>>> Thanks for your reply.

>>>

>>> 1. Register device as wakeup_source.

>>>  device_init_wakeup(dev, true) on probe()

>>>       device_wakeup_enable(dev)

>>>               device_source_register(const char *name)

>>>                       struct wakeup_source *ws;

>>>                       ws = wakeup_source_create(name)

>>>                       if (ws)

>>>                               wakeup_source_add(ws);

>>>                                       ...

>>>                                       list_add_rcu(&ws->entry, &wakeup_sources);

>>>                                       ...

>>>                       return ws;

>>>

>>>

>>> 2. Register the interrupt as wake_irq

>>> dev_pm_set_wake_irq(struct device *dev, int irq) on probe()

>>>       struct wake_irq *wirq;

>>>       wirq->dev = dev;

>>>       wirq->irq = irq;

>>>       dev_pm_attach_wake_irq(dev, irq, wirq);

>>>               device_wakeup_attach_irq(*dev, *wakeirq)

>>>                       struct wakeup_source *ws;

>>>                       ws = dev->power.wakeup;

>>>                       ws->wakeirq = wakeirq;

>>>

>>>

>>> 3. Enable irq wake if device is already registed to wakeup_sources.

>>> dpm_suspend_noirq()

>>>       device_wakeup_arm_wake_irqs()

>>>               list_for_each_entry_rcu(ws, &wakeup_sources, entry) {

>>>                       if (ws->wakeirq)

>>>                               dev_pm_arm_wake_irq(sw->wakeirq);

>>>                                       if (device_may_wakeup(wirq->dev))

>>>                                               enable_irq_wake(wirq->irq);

>>>

>>>

>>> To Roger,

>>>

>>> How about using the queue_delayed_work() instead of direct call function?

>>> Because the spent time of wakeup from suspend state should be fast.

>>> So, I think that you better to use the queue_delayed_work().

>>>

>>> diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c

>>> index 118f8ab3be73..f6cbdfe31519 100644

>>> --- a/drivers/extcon/extcon-usb-gpio.c

>>> +++ b/drivers/extcon/extcon-usb-gpio.c

>>> @@ -186,7 +186,9 @@ static int usb_extcon_resume(struct device *dev)

>>>

>>>         enable_irq(info->id_irq);

>>>         if (!device_may_wakeup(dev))

>>> -               usb_extcon_detect_cable(&info->wq_detcable.work);

>>> +               queue_delayed_work(system_power_efficient_wq,

>>> +                               &info->wq_detcable,

>>> +                               info->debounce_jiffies);

>>

>> Why not to just use queue_work() instead of queue_delayed_work()

>> as don't need to debounce the input?

> 

> The use of queue_work() is good.


Unfortunately we can't as info->wq_detcable type is 'struct delayed_work' but
queue_work() expects 'struct work_struct'

I'll just call queue_delayed_work() with 0 delay :)

cheers,
-roger
diff mbox

Patch

diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c
index bc61d11..118f8ab 100644
--- a/drivers/extcon/extcon-usb-gpio.c
+++ b/drivers/extcon/extcon-usb-gpio.c
@@ -185,6 +185,8 @@  static int usb_extcon_resume(struct device *dev)
 	int ret = 0;
 
 	enable_irq(info->id_irq);
+	if (!device_may_wakeup(dev))
+		usb_extcon_detect_cable(&info->wq_detcable.work);
 
 	return ret;
 }