Re: [PATCH] Bluetooth: btusb: request wake pin with NOAUTOEN

From: Brian Norris
Date: Tue Mar 26 2019 - 14:49:06 EST


On Thu, Feb 21, 2019 at 4:30 PM Brian Norris <briannorris@xxxxxxxxxxxx> wrote:
>
> Badly-designed systems might have (for example) active-high wake pins
> that default to high (e.g., because of external pull ups) until they
> have an active firmware which starts driving it low. This can cause an
> interrupt storm in the time between request_irq() and disable_irq().
>
> We don't support shared interrupts here, so let's just pre-configure the
> interrupt to avoid auto-enabling it.
>
> Fixes: fd913ef7ce61 ("Bluetooth: btusb: Add out-of-band wakeup support")
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>

Ping! v5.1 is enabling wake support on Scarlet, and without this
patch, that causes interrupt storms at boot. Please apply this patch
for v5.1-rc!

See also:
https://lkml.kernel.org/lkml/CA+ASDXMePkQDRfaSwNGnRYyGdsuvfUCXBtDK79o2mP=1hdNQUA@xxxxxxxxxxxxxx

Brian