[PATCH 12/12] au0828: Add timer to restart TS stream if no data arrives on bulk endpoint

[Devin Heitmueller]

For reasons unclear, we intermittently see a case where the tune
is successful but the bulk stream fails to deliver any packets.

Add a timer to automatically stop/start the data pump if we
encounter such a case.

Signed-off-by: Devin Heitmueller <dheitmuel...@kernellabs.com>
---
 drivers/media/usb/au0828/au0828-dvb.c | 30 ++++++++++++++++++++++++++++++
 drivers/media/usb/au0828/au0828.h     |  2 ++
 2 files changed, 32 insertions(+)

diff --git a/drivers/media/usb/au0828/au0828-dvb.c 
b/drivers/media/usb/au0828/au0828-dvb.c
index 7e0c9b7..34dc7e0 100644
--- a/drivers/media/usb/au0828/au0828-dvb.c
+++ b/drivers/media/usb/au0828/au0828-dvb.c
@@ -105,6 +105,15 @@
 
 static void au0828_restart_dvb_streaming(struct work_struct *work);
 
+static void au0828_bulk_timeout(unsigned long data)
+{
+       struct au0828_dev *dev = (struct au0828_dev *) data;
+
+       dprintk(1, "%s called\n", __func__);
+       dev->bulk_timeout_running = 0;
+       schedule_work(&dev->restart_streaming);
+}
+
 /*-------------------------------------------------------------------*/
 static void urb_completion(struct urb *purb)
 {
@@ -138,6 +147,13 @@ static void urb_completion(struct urb *purb)
                        ptr[0], purb->actual_length);
                schedule_work(&dev->restart_streaming);
                return;
+       } else if (dev->bulk_timeout_running == 1) {
+               /* The URB handler has fired, so cancel timer which would
+                * restart endpoint if we hadn't
+                */
+               dprintk(1, "%s cancelling bulk timeout\n", __func__);
+               dev->bulk_timeout_running = 0;
+               del_timer(&dev->bulk_timeout);
        }
 
        /* Feed the transport payload into the kernel demux */
@@ -160,6 +176,11 @@ static int stop_urb_transfer(struct au0828_dev *dev)
        if (!dev->urb_streaming)
                return 0;
 
+       if (dev->bulk_timeout_running == 1) {
+               dev->bulk_timeout_running = 0;
+               del_timer(&dev->bulk_timeout);
+       }
+
        dev->urb_streaming = false;
        for (i = 0; i < URB_COUNT; i++) {
                if (dev->urbs[i]) {
@@ -232,6 +253,11 @@ static int start_urb_transfer(struct au0828_dev *dev)
        }
 
        dev->urb_streaming = true;
+
+       /* If we don't valid data within 1 second, restart stream */
+       mod_timer(&dev->bulk_timeout, jiffies + (HZ));
+       dev->bulk_timeout_running = 1;
+
        return 0;
 }
 
@@ -622,6 +648,10 @@ int au0828_dvb_register(struct au0828_dev *dev)
                return ret;
        }
 
+       dev->bulk_timeout.function = au0828_bulk_timeout;
+       dev->bulk_timeout.data = (unsigned long) dev;
+       init_timer(&dev->bulk_timeout);
+
        return 0;
 }
 
diff --git a/drivers/media/usb/au0828/au0828.h 
b/drivers/media/usb/au0828/au0828.h
index 88e5974..05e445f 100644
--- a/drivers/media/usb/au0828/au0828.h
+++ b/drivers/media/usb/au0828/au0828.h
@@ -195,6 +195,8 @@ struct au0828_dev {
        /* Digital */
        struct au0828_dvb               dvb;
        struct work_struct              restart_streaming;
+       struct timer_list               bulk_timeout;
+       int                             bulk_timeout_running;
 
 #ifdef CONFIG_VIDEO_AU0828_V4L2
        /* Analog */
-- 
1.9.1