[media] au8522: properly recover from the au8522 delivering misaligned TS streams

There is an apparent bug in the au8522 TS clocking which can result in
it delivering a TS payload to the au0828 that is shifted by some number
of bits. For example, the device will announce a packet containing "FA
38 FF F8" which if you shift left one bit is "1F 47 1F FF F0..."

This presents itself as no TS stream being delivered from the kernel to
userland, since the kernel demux will drop every packet.

In the event that this condition occurs, restart the DVB stream.

Also, this patch includes a couple of lines of cleanup to not change the
FIFO configuration while the FIFO is running (which can screw up the
state machine), and dequeue the buffers before turning off the FIFO.
This puts the logic in sync with the Windows driver.

Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/video/au0828/au0828-dvb.c b/drivers/media/video/au0828/au0828-dvb.c
index 39ece8e2498578d68664d49568ecec26aeb1a616..b328f6550d0b28714ff7339e08844e5491c8b407 100644 (file)
--- a/drivers/media/video/au0828/au0828-dvb.c
+++ b/drivers/media/video/au0828/au0828-dvb.c
@@ -101,11 +101,14 @@ static struct tda18271_config hauppauge_woodbury_tunerconfig = {
        .gate    = TDA18271_GATE_DIGITAL,
 };
 
+static void au0828_restart_dvb_streaming(struct work_struct *work);
+
 /*-------------------------------------------------------------------*/
 static void urb_completion(struct urb *purb)
 {
        struct au0828_dev *dev = purb->context;
        int ptype = usb_pipetype(purb->pipe);
+       unsigned char *ptr;
 
        dprintk(2, "%s()\n", __func__);
 
@@ -121,6 +124,16 @@ static void urb_completion(struct urb *purb)
                return;
        }
 
+       /* See if the stream is corrupted (to work around a hardware
+          bug where the stream gets misaligned */
+       ptr = purb->transfer_buffer;
+       if (purb->actual_length > 0 && ptr[0] != 0x47) {
+               dprintk(1, "Need to restart streaming %02x len=%d!\n",
+                       ptr[0], purb->actual_length);
+               schedule_work(&dev->restart_streaming);
+               return;
+       }
+
        /* Feed the transport payload into the kernel demux */
        dvb_dmx_swfilter_packets(&dev->dvb.demux,
                purb->transfer_buffer, purb->actual_length / 188);
@@ -138,14 +151,13 @@ static int stop_urb_transfer(struct au0828_dev *dev)
 
        dprintk(2, "%s()\n", __func__);
 
+       dev->urb_streaming = 0;
        for (i = 0; i < URB_COUNT; i++) {
                usb_kill_urb(dev->urbs[i]);
                kfree(dev->urbs[i]->transfer_buffer);
                usb_free_urb(dev->urbs[i]);
        }
 
-       dev->urb_streaming = 0;
-
        return 0;
 }
 
@@ -246,11 +258,8 @@ static int au0828_dvb_stop_feed(struct dvb_demux_feed *feed)
                mutex_lock(&dvb->lock);
                if (--dvb->feeding == 0) {
                        /* Stop transport */
-                       au0828_write(dev, 0x608, 0x00);
-                       au0828_write(dev, 0x609, 0x00);
-                       au0828_write(dev, 0x60a, 0x00);
-                       au0828_write(dev, 0x60b, 0x00);
                        ret = stop_urb_transfer(dev);
+                       au0828_write(dev, 0x60b, 0x00);
                }
                mutex_unlock(&dvb->lock);
        }
@@ -258,6 +267,37 @@ static int au0828_dvb_stop_feed(struct dvb_demux_feed *feed)
        return ret;
 }
 
+static void au0828_restart_dvb_streaming(struct work_struct *work)
+{
+       struct au0828_dev *dev = container_of(work, struct au0828_dev,
+                                             restart_streaming);
+       struct au0828_dvb *dvb = &dev->dvb;
+       int ret;
+
+       if (dev->urb_streaming == 0)
+               return;
+
+       dprintk(1, "Restarting streaming...!\n");
+
+       mutex_lock(&dvb->lock);
+
+       /* Stop transport */
+       ret = stop_urb_transfer(dev);
+       au0828_write(dev, 0x608, 0x00);
+       au0828_write(dev, 0x609, 0x00);
+       au0828_write(dev, 0x60a, 0x00);
+       au0828_write(dev, 0x60b, 0x00);
+
+       /* Start transport */
+       au0828_write(dev, 0x608, 0x90);
+       au0828_write(dev, 0x609, 0x72);
+       au0828_write(dev, 0x60a, 0x71);
+       au0828_write(dev, 0x60b, 0x01);
+       ret = start_urb_transfer(dev);
+
+       mutex_unlock(&dvb->lock);
+}
+
 static int dvb_register(struct au0828_dev *dev)
 {
        struct au0828_dvb *dvb = &dev->dvb;
@@ -265,6 +305,8 @@ static int dvb_register(struct au0828_dev *dev)
 
        dprintk(1, "%s()\n", __func__);
 
+       INIT_WORK(&dev->restart_streaming, au0828_restart_dvb_streaming);
+
        /* register adapter */
        result = dvb_register_adapter(&dvb->adapter, DRIVER_NAME, THIS_MODULE,
                                      &dev->usbdev->dev, adapter_nr);

diff --git a/drivers/media/video/au0828/au0828.h b/drivers/media/video/au0828/au0828.h
index 9cde3532182414dc1a72ec265714015453c29fbb..61cd63e2bc6341242071b3ea61c5fc3b2a07890e 100644 (file)
--- a/drivers/media/video/au0828/au0828.h
+++ b/drivers/media/video/au0828/au0828.h
@@ -197,6 +197,7 @@ struct au0828_dev {
 
        /* Digital */
        struct au0828_dvb               dvb;
+       struct work_struct              restart_streaming;
 
        /* Analog */
        struct v4l2_device v4l2_dev;