Subject: [PATCH v4 1/3] genirq: Allow the irqchip state of an IRQ to be save/restored

From: [email-masked] (Marc Zyngier)
Date: Mon, 13 Apr 2015 17:21:18 +0100

On 13/04/15 17:18, Srinivas Kandagatla wrote:
> 
> 
> On 08/04/15 18:48, Bjorn Andersson wrote:
>> On Wed, Mar 18, 2015 at 4:01 AM, Marc Zyngier <[email-masked]> wrote:
>>> There is a number of cases where a kernel subsystem may want to
>>> introspect the state of an interrupt at the irqchip level:
>>>
>>> - When a peripheral is shared between virtual machines,
>>>    its interrupt state becomes part of the guest's state,
>>>    and must be switched accordingly. KVM on arm/arm64 requires
>>>    this for its guest-visible timer
>>> - Some GPIO controllers seem to require peeking into the
>>>    interrupt controller they are connected to to report
>>>    their internal state
>>>
>>> This seem to be a pattern that is common enough for the core code
>>> to try and support this without too many horrible hacks. Introduce
>>> a pair of accessors (irq_get_irqchip_state/irq_set_irqchip_state)
>>> to retrieve the bits that can be of interest to another subsystem:
>>> pending, active, and masked.
>>>
>>> - irq_get_irqchip_state returns the state of the interrupt according
>>>    to a parameter set to IRQCHIP_STATE_PENDING, IRQCHIP_STATE_ACTIVE,
>>>    IRQCHIP_STATE_MASKED or IRQCHIP_STATE_LINE_LEVEL.
>>> - irq_set_irqchip_state similarly sets the state of the interrupt.
>>>
>>> Reviewed-by: Bjorn Andersson <[email-masked]>
>>> Tested-by: Bjorn Andersson <[email-masked]>
>>> Signed-off-by: Marc Zyngier <[email-masked]>
>>> ---
>>
>> Sorry for bothering you Thomas, but we have a couple of driver for the
>> Qualcomm platforms that depends on this patch (the line level part).
> 
> +1
> 
> Couple of Qualcomm board support are left incomplete due to missing 
> drivers using these patches.
> Would be nice to get this patch mainlined sooner.

These patches are already in -next. Should everything go according to
plan, they should hit 4.1.

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...