[PULL -- 5.1 REGRESSION] Bluetooth: btusb: request wake pin with NOAUTOEN

From: Brian Norris
Date: Tue Apr 09 2019 - 14:49:50 EST


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")
Fixes: 5364a0b4f4be ("arm64: dts: rockchip: move QCA6174A wakeup pin into its USB node")
Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
---
Hi Linus,

Can you please apply this for v5.1-rc5? This fixes a regression that I
reported several times. I nearly just sent a proper pull request, but I
figured this 2-line patch was clearer.

This patch was originally sent here:
https://lore.kernel.org/patchwork/patch/1044896/
https://lkml.kernel.org/lkml/20190222003051.127006-1-briannorris@xxxxxxxxxxxx/

My other series was merged, even though it gave a clear dependency on
this bugfix:

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

Several pings were ignored, so here I'm submitting this to you, Linus.

Thanks,
Brian

drivers/bluetooth/btusb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index ded198328f21..7db48ae65cd2 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -2942,6 +2942,7 @@ static int btusb_config_oob_wake(struct hci_dev *hdev)
return 0;
}

+ irq_set_status_flags(irq, IRQ_NOAUTOEN);
ret = devm_request_irq(&hdev->dev, irq, btusb_oob_wake_handler,
0, "OOB Wake-on-BT", data);
if (ret) {
@@ -2956,7 +2957,6 @@ static int btusb_config_oob_wake(struct hci_dev *hdev)
}

data->oob_wake_irq = irq;
- disable_irq(irq);
bt_dev_info(hdev, "OOB Wake-on-BT configured at IRQ %u", irq);
return 0;
}
--
2.21.0.392.gf8f6787159e-goog