V4L/DVB (9595): cx18: Improve handling of outgoing mailboxes detected to be busy

cx18: Improve handling of outgoing mailboxes detected to be busy.  When
encountering a busy mailbox, sleep instead of polling, and wait for interrupt or
timeout.  If the mailbox is still busy, force it free.  When sending commands,
make sure we never create a situation where we mark the mailbox busy upon
sending, and ensure we always have a method to cleanly recover from a busy
mailbox.

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/media/video/cx18/cx18-irq.c b/drivers/media/video/cx18/cx18-irq.c
index 37b931055d3a..4912b3c8e6a5 100644
--- a/drivers/media/video/cx18/cx18-irq.c
+++ b/drivers/media/video/cx18/cx18-irq.c
@@ -167,7 +167,8 @@ irqreturn_t cx18_irq_handler(int irq, void *dev_id)
                 cx18_write_reg_expect(cx, hw2, HW2_INT_CLR_STATUS, ~hw2, hw2);
 
         if (sw1 || sw2 || hw2)
-                CX18_DEBUG_HI_IRQ("SW1: %x  SW2: %x  HW2: %x\n", sw1, sw2, hw2);
+                CX18_DEBUG_HI_IRQ("received interrupts "
+                                  "SW1: %x  SW2: %x  HW2: %x\n", sw1, sw2, hw2);
 
         /* To do: interrupt-based I2C handling
         if (hw2 & (HW2_I2C1_INT|HW2_I2C2_INT)) {