Re: [PATCH v6 1/4] mfd: add support for Diolan DLN-2 devices

[Octavian Purdila]

On Wed, Oct 8, 2014 at 3:04 PM, Johan Hovold <johan@xxxxxxxxxx> wrote:
> On Wed, Oct 08, 2014 at 01:54:07PM +0300, Octavian Purdila wrote:
>> On Wed, Oct 8, 2014 at 12:23 PM, Johan Hovold <johan@xxxxxxxxxx> wrote:
>> > On Thu, Sep 25, 2014 at 07:07:31PM +0300, Octavian Purdila wrote:
>> >
>> >> +static void dln2_rx_transfer(struct dln2_dev *dln2, struct urb *urb,
>> >> +                          u16 handle, u16 rx_slot)
>> >> +{
>> >> +     struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
>> >> +     struct dln2_rx_context *rxc;
>> >> +     struct device *dev = &dln2->interface->dev;
>> >> +
>> >> +     spin_lock(&rxs->lock);
>> >
>> > You must use spin_lock_irqsave here as you call it from the completion
>> > handler.
>>
>> Why? AFAICS the completion handler gets called from the HCD irq handler:
>
> The completion handler is currently called with local interrupts
> disabled but that is about to change once all drivers have been updated:
>
>         http://marc.info/?l=linux-usb&m=137353360511003&w=2
>
> In this case you could probably get away with not disabling interrupts
> anyway, but using the irqsave versions would make it obvious.
>

I was not assuming that interrupts are disabled while running the
completion handler. Since that spinlock is not touched by any other
interrupt context code I don't think irqsave is necessary.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/