The Linux kernel reports a canbus message as transmitted when it gets
the echo frame back. Processing the message prior to sending the echo
frame can lead to odd looking debugging logs (as the response messages
may appear to predate the request messages). This doesn't impact the
Klipper code, but it does make analyzing logs harder. Fix by sending
the echo frame prior to processing the frame.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Don't limit the canbus_notify_tx() wakeup to cases where notify_local
is set - perform the wakeup whenever the host_status field indicates
the main task has work pending.
This fixes a small race condition where the main task could block
sending a usb echo frame, and the canbus_send() code gets called as
the usb bandwidth becomes available but before a usb wakeup
notification is sent. In that situation, the usb code may not issue a
wake event and the echo frames may be delayed.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
If the low-level canbus stops working then it could become impossible
to send messages to and from the canbus bridge node itself. This can
make it difficult to diagnose canbus problems.
Change the canbus bridge code to detect if message transmits become
stalled for 50+ milliseconds and go into a "discarding" state. In
this discarding state, messages destined for the canbus will be
discarded until the canbus becomes active again. In this discarding
state it will therefore be possible to transmit messages to and from
the canbus bridge node.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Prioritize sending responses back to the host over transmitting new
messages from the host. Otherwise, the gs_usb host usb
acknowledgments could saturate the usb bandwidth for extended periods.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Read USB messages arriving from the host into a queue. This makes it
less likely that USB "bulk out" packets will be NAK'ed on the USB bus,
which improves USB bus utilization.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
There is no need to heavily prioritize the sending of canbus packets
over USB. A single check to flush the incoming canbus packets is
sufficient.
Also, be sure to wake up canserial_notify_tx() even if canhw_send()
blocks.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
The canserial code already advertizes a receive window, so the host
should never flood the canserial code. Remove the extra scheduling
checks to simplify the usb_canbus code.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
A buffer of only 8 canbus packets is only 64 bytes of data, which
could be exceeded if the usb-to-canbus mcu gets busy doing other work.
Increase the buffer to 32 packets.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Rename canserial_send() to canbus_send() and canserial_set_filter() to
canbus_set_filter(). This makes it more clear where the code should
reside.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Rename canbus_send() to canhw_send() and rename canbus_set_filter() to
canhw_set_filter(). This makes it more clear where the code should
reside.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
An mcu device acting as an "mcu bridge" should only be reset after
other normal devices are reset - otherwise the bridge wont be able to
pass along the reset message to the downstream mcus.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
Support a USB interface that shows up as a canbus adapter to linux.
Route both local and real canbus packets over that interface.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
