linux-toradex.git/drivers/net/can/usb, branch v4.0.4

can: peak_usb_fd: add support for ISO / non-ISO mode switching

2015-03-22T17:14:51+00:00

The PCAN USB (pro) FD adapters with firmware versions > 2.x support the
switching between ISO (default) and non-ISO conform bitstreams on the CAN bus.
The setting for the 2.x firmware adapters can be modified with the 'ip' tool
from the iproute2 package (option: fd-non-iso [on|off]).

Signed-off-by: Stephane Grosjean 
Signed-off-by: Oliver Hartkopp 
Tested-by: Oliver Hartkopp 
Signed-off-by: Marc Kleine-Budde

can: peak_usb: rename usb option cmds definition and structs

2015-03-22T17:14:50+00:00

The PUCAN_CMD_RX_FRAME_(ENABLE|DISABLE) command has extended its purpose
and was therefore renamed to PUCAN_CMD_SET_(EN|DIS)_OPTION.

Signed-off-by: Stephane Grosjean 
Signed-off-by: Oliver Hartkopp 
Tested-by: Oliver Hartkopp 
Signed-off-by: Marc Kleine-Budde

can: gs_usb: check for kzalloc allocation failure

2015-03-22T17:14:50+00:00

smatch detected the following issue:
drivers/net/can/usb/gs_usb.c:904 gs_usb_probe() error:
   potential null dereference 'dev'.  (kzalloc returns null)

Add a check for null return from kzalloc and return -ENOMEM

Signed-off-by: Colin Ian King 
Signed-off-by: Marc Kleine-Budde

can: kvaser_usb: Fix sparse warning __le16 degrades to integer

2015-03-22T17:14:50+00:00

USB endpoint's wMaxPacketSize field is an le16 entity. Use
appropriate le16_to_cpu macros to maintain endian independence.

Reported-by: Marc Kleine-Budde 
Signed-off-by: Ahmed S. Darwish 
Signed-off-by: Marc Kleine-Budde

can: kvaser_usb: Comply with firmware max tx URBs value

2015-03-22T17:14:49+00:00

Current driver code arbitrarily assumes a max outstanding tx
value of 16 parallel transmissions. Meanwhile, the device
firmware provides its actual maximum inside its reply to the
CMD_GET_SOFTWARE_INFO message.

Under heavy tx traffic, if the interleaved transmissions count
increases above the limit reported by firmware, the firmware
breaks up badly, reports a massive list of internal errors, and
the candump traces hardly matches the actual frames sent and
received.

On the other hand, in certain models, the firmware can support
up to 48 tx URBs instead of just 16, increasing the driver
throughput by two-fold and reducing the possibility of -ENOBUFs.

Thus dynamically set the driver's max tx URBs value according
to firmware replies.

Signed-off-by: Ahmed S. Darwish 
Signed-off-by: Marc Kleine-Budde

can: kvaser_usb: Fix tx queue start/stop race conditions

2015-03-14T08:20:07+00:00

A number of tx queue wake-up events went missing due to the
outlined scenario below. Start state is a pool of 16 tx URBs,
active tx_urbs count = 15, with the netdev tx queue open.

CPU #1 [softirq]                         CPU #2 [softirq]
start_xmit()                             tx_acknowledge()
................                         ................

atomic_inc(&tx_urbs);
if (atomic_read(&tx_urbs) >= 16) {
                        -->
                                         atomic_dec(&tx_urbs);
                                         netif_wake_queue();
                                         return;
                        <--
    netif_stop_queue();
}

At the end, the correct state expected is a 15 tx_urbs count
value with the tx queue state _open_. Due to the race, we get
the same tx_urbs value but with the tx queue state _stopped_.
The wake-up event is completely lost.

Thus avoid hand-rolled concurrency mechanisms and use a proper
lock for contexts and tx queue protection.

Signed-off-by: Ahmed S. Darwish 
Cc: linux-stable 
Signed-off-by: Marc Kleine-Budde

can: kvaser_usb: Read all messages in a bulk-in URB buffer

2015-03-09T09:22:24+00:00

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

can: kvaser_usb: Avoid double free on URB submission failures

2015-03-09T09:22:24+00:00

Upon a URB submission failure, the driver calls usb_free_urb()
but then manually frees the URB buffer by itself.  Meanwhile
usb_free_urb() has alredy freed out that transfer buffer since
we're the only code path holding a reference to this URB.

Remove two of such invalid manual free().

Signed-off-by: Ahmed S. Darwish 
Cc: linux-stable 
Signed-off-by: Marc Kleine-Budde

can: peak_usb: fix missing ctrlmode_ init for every dev

2015-03-09T09:22:24+00:00

Fixes a missing initialization of ctrlmode and ctrlmode_supported fields,
for all other CAN devices than the first one. This fix only concerns
the PCAN-USB Pro FD dual-channels CAN-FD device made by PEAK-System.

Signed-off-by: Stephane Grosjean 
Signed-off-by: Marc Kleine-Budde

can: kvaser_usb: Ignore spurious error events after a busoff

2015-02-04T13:07:03+00:00

Sending data in high speed then introducing a busoff results
in spurious BUS_ERROR events from the USBCan-II firmware directly
_after_ the triggered BUS_OFF event.

In the current CAN state handling code, this will lead to an
invalid can state of ACTIVE, ERROR, or PASSIVE even though the
CAN controller has been already shut down due to the busoff.

Guard the state handling code from such invalid events.

Signed-off-by: Ahmed S. Darwish 
Signed-off-by: Marc Kleine-Budde