Make the pvrusb2 driver more tolerant of USB streaming errors

From: Mike Isely <isely@pobox.com>

Signed-off-by: Mike Isely <isely@pobox.com>

6 files changed, 76 insertions, 10 deletions

diff --git a/v4l/ChangeLog b/v4l/ChangeLog
index 2626d66cb..ca7e23ba9 100644
--- a/v4l/ChangeLog
+++ b/v4l/ChangeLog
@@ -1,3 +1,21 @@
+2006-01-09 06:50  mcisely
+
+	* v4l_experimental/pvrusb2/pvrusb2-debug.h:
+	* v4l_experimental/pvrusb2/pvrusb2-hdw.c:
+	(get_default_error_tolerance), (pvr2_hdw_setup_low),
+	(pvr2_hdw_render_useless_unlocked):
+	* v4l_experimental/pvrusb2/pvrusb2-io.c: (buffer_complete),
+	(pvr2_stream_setup):
+	* v4l_experimental/pvrusb2/pvrusb2-io.h:
+	* v4l_experimental/pvrusb2/pvrusb2-main.c:
+
+	- Implement new feature in pvrusb2 (which must be enabled via a
+	  module option) that permits the streaming logic to tolerate a
+	  specified level of USB errors.  This change makes it possible to
+	  still function in environments with flakey USB hardware.
+
+	Signed-off-by: Mike Isely <isely@pobox.com>
+
 2006-01-09 06:42  mcisely
 
 	* v4l_experimental/pvrusb2/pvrusb2-hdw.c:
diff --git a/v4l_experimental/pvrusb2/pvrusb2-debug.h b/v4l_experimental/pvrusb2/pvrusb2-debug.h
index 3f58eef94..b0616e6f4 100644
--- a/v4l_experimental/pvrusb2/pvrusb2-debug.h
+++ b/v4l_experimental/pvrusb2/pvrusb2-debug.h
@@ -1,5 +1,5 @@
 /*
- *  $Id: pvrusb2-debug.h,v 1.3 2006/01/09 06:24:23 mcisely Exp $
+ *  $Id: pvrusb2-debug.h,v 1.4 2006/01/09 06:54:46 mcisely Exp $
  *
  *  Copyright (C) 2005 Mike Isely <isely@pobox.com>
  *
@@ -28,6 +28,7 @@ extern int debug;
    increasing noise level. */
 #define PVR2_TRACE_INFO       (1 <<  0) // Normal messages
 #define PVR2_TRACE_ERROR_LEGS (1 <<  1) // error messages
+#define PVR2_TRACE_TOLERANCE  (1 <<  2) // track tolerance-affected errors
 #define PVR2_TRACE_TRAP       (1 <<  3) // Trap & report misbehavior from app
 #define PVR2_TRACE_INIT       (1 <<  4) // misc initialization steps
 #define PVR2_TRACE_START_STOP (1 <<  5) // Streaming start / stop
diff --git a/v4l_experimental/pvrusb2/pvrusb2-hdw.c b/v4l_experimental/pvrusb2/pvrusb2-hdw.c
index 15969ac46..2c6bfc949 100644
--- a/v4l_experimental/pvrusb2/pvrusb2-hdw.c
+++ b/v4l_experimental/pvrusb2/pvrusb2-hdw.c
@@ -1,6 +1,6 @@
 /*
  *
- *  $Id: pvrusb2-hdw.c,v 1.9 2006/01/09 06:45:51 mcisely Exp $
+ *  $Id: pvrusb2-hdw.c,v 1.10 2006/01/09 06:54:46 mcisely Exp $
  *
  *  Copyright (C) 2005 Mike Isely <isely@pobox.com>
  *
@@ -44,6 +44,7 @@ static int ctlchg = 0;
 static int initusbreset = 1;
 static int procreload = 0;
 static int tuner[PVR_NUM] = { [0 ... PVR_NUM-1] = -1 };
+static int tolerance[PVR_NUM] = { [0 ... PVR_NUM-1] = 0 };
 
 module_param(ctlchg, int, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(ctlchg, "0=optimize ctl change 1=always accept new ctl value");
@@ -58,6 +59,8 @@ module_param(width, int, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(width, "video width : 720,480,352");
 module_param_array(tuner,    int, NULL, 0444);
 MODULE_PARM_DESC(tuner,"specify installed tuner type");
+module_param_array(tolerance,    int, NULL, 0444);
+MODULE_PARM_DESC(tolerance,"specify stream error tolerance");
 
 #define PVR2_CTL_WRITE_ENDPOINT  0x01
 #define PVR2_CTL_READ_ENDPOINT   0x81
@@ -944,6 +947,17 @@ static int get_default_tuner_type(struct pvr2_hdw *hdw)
 }
 
 
+static unsigned int get_default_error_tolerance(struct pvr2_hdw *hdw)
+{
+	int unit_number = hdw->unit_number;
+	int tp = 0;
+	if ((unit_number >= 0) && (unit_number < PVR_NUM)) {
+		tp = tolerance[unit_number];
+	}
+	return tp;
+}
+
+
 static void pvr2_hdw_setup_low(struct pvr2_hdw *hdw)
 {
 	unsigned int idx;
@@ -1005,8 +1019,15 @@ static void pvr2_hdw_setup_low(struct pvr2_hdw *hdw)
 	pvr2_trace(PVR2_TRACE_INIT,
 		   "pvr2_hdw_setup: video stream is %p",hdw->vid_stream);
 	if (hdw->vid_stream) {
+		idx = get_default_error_tolerance(hdw);
+		if (idx) {
+			pvr2_trace(PVR2_TRACE_INIT,
+				   "pvr2_hdw_setup: video stream %p"
+				   " setting tolerance %u",
+				   hdw->vid_stream,idx);
+		}
 		pvr2_stream_setup(hdw->vid_stream,hdw->usb_dev,
-				  PVR2_VID_ENDPOINT);
+				  PVR2_VID_ENDPOINT,idx);
 	}
 
 	if (!pvr2_hdw_dev_ok(hdw)) return;
@@ -2129,7 +2150,7 @@ void pvr2_hdw_render_useless_unlocked(struct pvr2_hdw *hdw)
 	pvr2_trace(PVR2_TRACE_INIT,"render_useless");
 	hdw->flag_ok = 0;
 	if (hdw->vid_stream) {
-		pvr2_stream_setup(hdw->vid_stream,0,0);
+		pvr2_stream_setup(hdw->vid_stream,0,0,0);
 	}
 	hdw->flag_streaming_enabled = 0;
 	hdw->subsys_enabled_mask = 0;
diff --git a/v4l_experimental/pvrusb2/pvrusb2-io.c b/v4l_experimental/pvrusb2/pvrusb2-io.c
index 935978a14..c170bede0 100644
--- a/v4l_experimental/pvrusb2/pvrusb2-io.c
+++ b/v4l_experimental/pvrusb2/pvrusb2-io.c
@@ -1,6 +1,6 @@
 /*
  *
- *  $Id: pvrusb2-io.c,v 1.1 2005/11/14 13:31:24 mchehab Exp $
+ *  $Id: pvrusb2-io.c,v 1.2 2006/01/09 06:54:46 mcisely Exp $
  *
  *  Copyright (C) 2005 Mike Isely <isely@pobox.com>
  *
@@ -86,6 +86,9 @@ struct pvr2_stream {
 	/* Overhead for mutex enforcement */
 	spinlock_t list_lock;
 	struct semaphore sem;
+	/* Tracking state for tolerating errors */
+	unsigned int fail_count;
+	unsigned int fail_tolerance;
 };
 
 struct pvr2_buffer {
@@ -437,19 +440,38 @@ static void buffer_complete(struct urb *urb, struct pt_regs *regs)
 {
 	struct pvr2_buffer *bp = urb->context;
 	struct pvr2_stream *sp;
+	unsigned long irq_flags;
 	BUFFER_CHECK(bp);
 	sp = bp->stream;
 	bp->used_count = 0;
+	bp->status = 0;
 	pvr2_trace(PVR2_TRACE_BUF_FLOW,
 		   "/*---TRACE_FLOW---*/ bufferComplete %p stat=%d cnt=%d",
 		   bp,urb->status,urb->actual_length);
+	spin_lock_irqsave(&sp->list_lock,irq_flags);
 	if ((!(urb->status)) ||
 	    (urb->status == -ENOENT) ||
 	    (urb->status == -ECONNRESET) ||
 	    (urb->status == -ESHUTDOWN)) {
 		bp->used_count = urb->actual_length;
+		if (sp->fail_count) {
+			pvr2_trace(PVR2_TRACE_TOLERANCE,
+				   "stream %p transfer ok"
+				   " - fail count reset",sp);
+			sp->fail_count = 0;
+		}
+	} else if (sp->fail_count < sp->fail_tolerance) {
+		// We can tolerate this error, because we're below the
+		// threshold...
+		(sp->fail_count)++;
+		pvr2_trace(PVR2_TRACE_TOLERANCE,
+			   "stream %p ignoring error %d"
+			   " - fail count increased to %u",
+			   sp,urb->status,sp->fail_count);
+	} else {
+		bp->status = urb->status;
 	}
-	bp->status = urb->status;
+	spin_unlock_irqrestore(&sp->list_lock,irq_flags);
 	pvr2_buffer_set_ready(bp);
 	if (sp && sp->callback_func) {
 		sp->callback_func(sp->callback_data);
@@ -477,12 +499,14 @@ void pvr2_stream_destroy(struct pvr2_stream *sp)
 
 void pvr2_stream_setup(struct pvr2_stream *sp,
                        struct usb_device *dev,
-                       int endpoint)
+                       int endpoint,
+		       unsigned int tolerance)
 {
 	down(&sp->sem); do {
 		pvr2_stream_internal_flush(sp);
 		sp->dev = dev;
 		sp->endpoint = endpoint;
+		sp->fail_tolerance = tolerance;
 	} while(0); up(&sp->sem);
 }
 
diff --git a/v4l_experimental/pvrusb2/pvrusb2-io.h b/v4l_experimental/pvrusb2/pvrusb2-io.h
index 17e01345b..5dc72b1ef 100644
--- a/v4l_experimental/pvrusb2/pvrusb2-io.h
+++ b/v4l_experimental/pvrusb2/pvrusb2-io.h
@@ -1,6 +1,6 @@
 /*
  *
- *  $Id: pvrusb2-io.h,v 1.1 2005/11/14 13:31:24 mchehab Exp $
+ *  $Id: pvrusb2-io.h,v 1.2 2006/01/09 06:54:46 mcisely Exp $
  *
  *  Copyright (C) 2005 Mike Isely <isely@pobox.com>
  *
@@ -42,7 +42,8 @@ const char *pvr2_buffer_state_decode(enum pvr2_buffer_state);
 struct pvr2_stream *pvr2_stream_create(void);
 void pvr2_stream_destroy(struct pvr2_stream *);
 void pvr2_stream_setup(struct pvr2_stream *,
-                       struct usb_device *dev,int endpoint);
+                       struct usb_device *dev,int endpoint,
+		       unsigned int tolerance);
 void pvr2_stream_set_callback(struct pvr2_stream *,
                               pvr2_stream_callback func,
                               void *data);
diff --git a/v4l_experimental/pvrusb2/pvrusb2-main.c b/v4l_experimental/pvrusb2/pvrusb2-main.c
index ffaaa4409..aa6fa7c9d 100644
--- a/v4l_experimental/pvrusb2/pvrusb2-main.c
+++ b/v4l_experimental/pvrusb2/pvrusb2-main.c
@@ -1,6 +1,6 @@
 /*
  *
- *  $Id: pvrusb2-main.c,v 1.3 2006/01/01 08:26:03 mcisely Exp $
+ *  $Id: pvrusb2-main.c,v 1.4 2006/01/09 06:54:46 mcisely Exp $
  *
  *  Copyright (C) 2005 Mike Isely <isely@pobox.com>
  *  Copyright (C) 2004 Aurelien Alleaume <slts@free.fr>
@@ -43,6 +43,7 @@
 
 #define DEFAULT_DEBUG_MASK (PVR2_TRACE_ERROR_LEGS| \
 			    PVR2_TRACE_INFO| \
+			    PVR2_TRACE_TOLERANCE| \
 			    PVR2_TRACE_TRAP| \
 			    PVR2_TRACE_FIRMWARE| \
 			    PVR2_TRACE_EEPROM | \