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Re: [PATCH v2 7/9] gpio: 104-idi-48: make use of raw_spinlock variants

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On Wed, Mar 22, 2017 at 1:44 PM, William Breathitt Gray
<vilhelm.gray@gmail.com> wrote:
> On Tue, Mar 21, 2017 at 05:43:07PM -0500, Julia Cartwright wrote:
>>The 104-idi-48 gpio driver currently implements an irq_chip for handling
>>interrupts; due to how irq_chip handling is done, it's necessary for the
>>irq_chip methods to be invoked from hardirq context, even on a a
>>real-time kernel.  Because the spinlock_t type becomes a "sleeping"
>>spinlock w/ RT kernels, it is not suitable to be used with irq_chips.
>>
>>A quick audit of the operations under the lock reveal that they do only
>>minimal, bounded work, and are therefore safe to do under a raw spinlock.
>>
>>Signed-off-by: Julia Cartwright <julia@ni.com>
>
> Hi Julia,
>
> This driver also uses a second spinlock_t, called ack_lock, to prevent
> reentrance into the idi_48_irq_handler function. Should ack_lock also be
> implemented as a raw_spinlock_t?

Hm, can I apply this one patch or not?

Linus Walleij

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[PATCH v2 0/9] fixup usage of non-raw spinlocks in irqchips Julia Cartwright <julia@ni.com> - 2017-03-22 01:00 +0100
  [PATCH v2 7/9] gpio: 104-idi-48: make use of raw_spinlock variants Julia Cartwright <julia@ni.com> - 2017-03-22 01:00 +0100
    Re: [PATCH v2 7/9] gpio: 104-idi-48: make use of raw_spinlock  variants William Breathitt Gray <vilhelm.gray@gmail.com> - 2017-03-22 14:00 +0100
      Re: [PATCH v2 7/9] gpio: 104-idi-48: make use of raw_spinlock  variants Julia Cartwright <julia@ni.com> - 2017-03-22 17:20 +0100
      Re: [PATCH v2 7/9] gpio: 104-idi-48: make use of raw_spinlock variants Linus Walleij <linus.walleij@linaro.org> - 2017-03-28 11:20 +0200
        Re: [PATCH v2 7/9] gpio: 104-idi-48: make use of raw_spinlock  variants William Breathitt Gray <vilhelm.gray@gmail.com> - 2017-03-28 13:50 +0200
    Re: [PATCH v2 7/9] gpio: 104-idi-48: make use of raw_spinlock variants Linus Walleij <linus.walleij@linaro.org> - 2017-03-28 15:10 +0200

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