Re: [PATCH] platform/surface: aggregator: move to use request_irq by IRQF_NO_AUTOEN flag

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 4/7/21 2:30 PM, tiantao (H) wrote:
> 
> 在 2021/4/7 17:51, Hans de Goede 写道:
>> Hi,
>>
>> On 4/7/21 9:00 AM, Tian Tao wrote:
>>> disable_irq() after request_irq() still has a time gap in which
>>> interrupts can come. request_irq() with IRQF_NO_AUTOEN flag will
>>> disable IRQ auto-enable because of requesting.
>> Thank you for your patch, it is good to see the issue of there not
>> being a simply way to request IRQs in a way where they are initially
>> disabled being solved.
>>
>>> this patch is made base on "add IRQF_NO_AUTOEN for request_irq" which
>>> is being merged: https://lore.kernel.org/patchwork/patch/1388765/
>> So this is not yet in Linus' tree. When you write "which is being merged",
>> I assume that means that this is going upstream in the 5.13 window.
> this is already in linux-next.git.
> 
> cbe16f3 genirq: Add IRQF_NO_AUTOEN for request_irq/nmi()

That does not help though, since all subsystem branches/trees, including
mine are based on 5.12-rc2, which does not contain the commit.

But I see that tglx has already created a signed-tag for the input-subsys
maintainer to solve the same issue, so I can just re-use that:

https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/tag/?h=irq-no-autoen-2021-03-25

Regards,

Hans



>>> Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
>>> ---
>>>   drivers/platform/surface/aggregator/controller.c | 4 ++--
>>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/platform/surface/aggregator/controller.c b/drivers/platform/surface/aggregator/controller.c
>>> index aa6f37b..00e3828 100644
>>> --- a/drivers/platform/surface/aggregator/controller.c
>>> +++ b/drivers/platform/surface/aggregator/controller.c
>>> @@ -2483,7 +2483,8 @@ int ssam_irq_setup(struct ssam_controller *ctrl)
>>>        * interrupt, and let the SAM resume callback during the controller
>>>        * resume process clear it.
>>>        */
>>> -    const int irqf = IRQF_SHARED | IRQF_ONESHOT | IRQF_TRIGGER_RISING;
>>> +    const int irqf = IRQF_SHARED | IRQF_ONESHOT |
>>> +             IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN;
>>>         gpiod = gpiod_get(dev, "ssam_wakeup-int", GPIOD_ASIS);
>>>       if (IS_ERR(gpiod))
>>> @@ -2501,7 +2502,6 @@ int ssam_irq_setup(struct ssam_controller *ctrl)
>>>           return status;
>>>         ctrl->irq.num = irq;
>>> -    disable_irq(ctrl->irq.num);
>>>       return 0;
>>>   }
>>>  
>> .
>>
>