On Sun, 14 Nov 2010 21:24:46 +0100
NÃmeth MÃrton <nm127@xxxxxxxxxxx> wrote:
> Sure, I'm happy as long as I can capture the whole data content of the ISO
> packets.
Great. So, what do you think about the attached? It differs from your
code in one important aspect: output buffer sizes are not adjusted.
Your patch attempts that, but uses actual_length, which is not
defined during submission events. So I skipped that.
-- Pete
diff --git a/drivers/usb/mon/mon_bin.c b/drivers/usb/mon/mon_bin.c
index 44cb37b..15c5e46 100644
--- a/drivers/usb/mon/mon_bin.c
+++ b/drivers/usb/mon/mon_bin.c
@@ -437,6 +437,28 @@ static unsigned int mon_bin_get_data(const struct mon_reader_bin *rp,
return length;
}
+/*
+ * This is the look-ahead pass in case of 'Ci', when actual_length cannot
+ * be used to determine the length of the whole contiguous buffer.
+ */
+static unsigned int mon_bin_collate_isodesc(const struct mon_reader_bin *rp,
+ struct urb *urb, unsigned int ndesc)
+{
+ struct usb_iso_packet_descriptor *fp;
+ unsigned int length;
+
+ length = 0;
+ fp = urb->iso_frame_desc;
+ while (ndesc-- != 0) {
+ if (fp->status == 0 && fp->actual_length != 0) {
+ if (fp->offset + fp->actual_length > length)
+ length = fp->offset + fp->actual_length;
+ }
+ fp++;
+ }
+ return length;
+}
+
static void mon_bin_get_isodesc(const struct mon_reader_bin *rp,
unsigned int offset, struct urb *urb, char ev_type, unsigned int ndesc)
{
@@ -479,6 +501,10 @@ static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
/*
* Find the maximum allowable length, then allocate space.
*/
+ urb_length = (ev_type == 'S') ?
+ urb->transfer_buffer_length : urb->actual_length;
+ length = urb_length;
+
if (usb_endpoint_xfer_isoc(epd)) {
if (urb->number_of_packets < 0) {
ndesc = 0;
@@ -487,14 +513,16 @@ static void mon_bin_event(struct mon_reader_bin *rp, struct urb *urb,
} else {
ndesc = urb->number_of_packets;
}
+ if (ev_type == 'C' && usb_urb_dir_in(urb))
+ length = mon_bin_collate_isodesc(rp, urb, ndesc);
} else {
ndesc = 0;
}
lendesc = ndesc*sizeof(struct mon_bin_isodesc);
- urb_length = (ev_type == 'S') ?
- urb->transfer_buffer_length : urb->actual_length;
- length = urb_length;
+ /* not an issue unless there's a subtle bug in a HCD somewhere */
+ if (length >= urb->transfer_buffer_length)
+ length = urb->transfer_buffer_length;
if (length >= rp->b_size/5)
length = rp->b_size/5;
--
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