[PATCH] usbfs: Increase arbitrary limit for USB 3 isopkt length

From: Federico Manzan
Date: Fri May 24 2013 - 04:47:04 EST


Increase the current arbitrary limit for isocronous packet size to a
value large enough to account for USB 3.0 super bandwidth streams,
bMaxBurst (0~15 allowed, 1~16 packets)
bmAttributes (bit 1:0, mult 0~2, 1~3 packets)
so the size max for one USB 3 isocronous transfer is
1024 byte * 16 * 3 = 49152 byte

Signed-off-by: Federico Manzan <f.manzan@xxxxxxxxx>
---
drivers/usb/core/devio.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index caefc80..7ac137e 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -1287,9 +1287,11 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb,
goto error;
}
for (totlen = u = 0; u < uurb->number_of_packets; u++) {
- /* arbitrary limit,
- * sufficient for USB 2.0 high-bandwidth iso */
- if (isopkt[u].length > 8192) {
+ /* arbitrary limit need for USB 3.0
+ * bMaxBurst (0~15 allowed, 1~16 packets)
+ * bmAttributes (bit 1:0, mult 0~2, 1~3 packets)
+ * sizemax: 1024 * 16 * 3 = 49152*/
+ if (isopkt[u].length > 65536) {
ret = -EINVAL;
goto error;
}
--
1.7.10.4

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