From 2fec5104f9c61de4cf2205aa355101e19a81f490 Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Thu, 26 Feb 2015 10:22:02 -0500 Subject: [PATCH] can: kvaser_usb: Read all messages in a bulk-in URB buffer The Kvaser firmware can only read and write messages that are not crossing the USB endpoint's wMaxPacketSize boundary. While receiving commands from the CAN device, if the next command in the same URB buffer crossed that max packet size boundary, the firmware puts a zero-length placeholder command in its place then moves the real command to the next boundary mark. The driver did not recognize such behavior, leading to missing a good number of rx events during a heavy rx load session. Moreover, a tx URB context only gets freed upon receiving its respective tx ACK event. Over time, the free tx URB contexts pool gets depleted due to the missing ACK events. Consequently, the netif transmission queue gets __permanently__ stopped; no frames could be sent again except after restarting the CAN newtwork interface. Signed-off-by: Ahmed S. Darwish Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- Reading git-format-patch failed