Bluetooth: Redo checks in IRQ handler for shared IRQ support

Commit ac019360fe3 changed the irq handler logic to BUG_ON rather than
returning IRQ_NONE when the incoming argument is invalid.  While this
works in most cases, it doesn't work when the IRQ is shared with other
devices (or when DEBUG_SHIRQ is enabled).

So revert the previous change and replace the warning message with a
comment explaining that we want this behavior.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/bluetooth/btuart_cs.c b/drivers/bluetooth/btuart_cs.c
index d339464dc15e..91c523099804 100644
--- a/drivers/bluetooth/btuart_cs.c
+++ b/drivers/bluetooth/btuart_cs.c
@@ -295,7 +295,9 @@ static irqreturn_t btuart_interrupt(int irq, void *dev_inst)
         int iir, lsr;
         irqreturn_t r = IRQ_NONE;
 
-        BUG_ON(!info->hdev);
+        if (!info || !info->hdev)
+                /* our irq handler is shared */
+                return IRQ_NONE;
 
         iobase = info->p_dev->io.BasePort1;