This is an automated email from Gerrit.
Tomas Vanek (van...@fbl.cz) just uploaded a new patch set to Gerrit, which you
can find at http://openocd.zylin.com/4426
-- gerrit
commit ded3fe536d6aaddd6d7beeea1fb1230f4bfd0afd
Author: Tomas Vanek <van...@fbl.cz>
Date: Wed Feb 21 22:19:58 2018 +0100
drivers/kitprog: workaround KitProg firmware bug of missing ZLP
KitProg firmware does not send a zero length packet at the end of the
bulk-in
transmission of a length divisible by a bulk packet size. This is
inconsistent
with the USB specification and results in jtag_libusb_bulk_read()
waits forever when a transmission of specific size is received.
Limit bulk read size to expected number of bytes for problematic tranfer
sizes.
Use 1 second timeout as the last resort.
Change-Id: Ice80306424afd76e9fbc6851911ffd5109c84501
Signed-off-by: Tomas Vanek <van...@fbl.cz>
diff --git a/src/jtag/drivers/kitprog.c b/src/jtag/drivers/kitprog.c
index db5b62e..522eb17 100644
--- a/src/jtag/drivers/kitprog.c
+++ b/src/jtag/drivers/kitprog.c
@@ -741,12 +741,22 @@ static int kitprog_swd_run_queue(void)
break;
}
- /* We use the maximum buffer size here because the KitProg
sometimes
- * doesn't like bulk reads of fewer than 62 bytes. (?!?!)
+ /* KitProg firmware does not send a zero length packet
+ * after the bulk-in transmission of a length divisible by bulk
packet
+ * size (64 bytes) as required by the USB specification.
+ * Therefore libusb would wait for continuation of transmission.
+ * Workaround: Limit bulk read size to expected number of bytes
+ * for problematic tranfer sizes. Otherwise use the maximum
buffer
+ * size here because the KitProg sometimes doesn't like bulk
reads
+ * of fewer than 62 bytes. (?!?!)
*/
+ size_t read_count_workaround = SWD_MAX_BUFFER_LENGTH;
+ if (read_count % 64 == 0)
+ read_count_workaround = read_count;
+
ret = jtag_libusb_bulk_read(kitprog_handle->usb_handle,
BULK_EP_IN | LIBUSB_ENDPOINT_IN, (char *)buffer,
- SWD_MAX_BUFFER_LENGTH, 0);
+ read_count_workaround, 1000);
if (ret > 0) {
/* Handle garbage data by offsetting the initial read
index */
if ((unsigned int)ret > read_count)
--
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