A "struct peak_usb_adapter" describes a certain USB adapter, as this doesn't
change during runtime, this patch marks all USB adapter definitions as const.
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch converts the list "static struct peak_usb_adapter
*peak_usb_adapters_list[]" to be used with ARRAY_SIZE not with a NULL
termination, as the size is known during compile time.
Acked-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

CAN to USB interfaces sold by the Swedish manufacturer Kvaser are
divided into two major families: 'Leaf', and 'USBcanII'.  From an
Operating System perspective, the firmware of both families behave
in a not too drastically different fashion.

This patch adds support for the USBcanII family of devices to the
current Kvaser Leaf-only driver.

CAN frames sending, receiving, and error handling paths has been
tested using the dual-channel "Kvaser USBcan II HS/LS" dongle. It
should also work nicely with other products in the same category.

List of new devices supported by this driver update:

         - Kvaser USBcan II HS/HS
         - Kvaser USBcan II HS/LS
         - Kvaser USBcan Rugged ("USBcan Rev B")
         - Kvaser Memorator HS/HS
         - Kvaser Memorator HS/LS
         - Scania VCI2 (if you have the Kvaser logo on top)
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Acked-by: NAndri Yngvason <andri.yngvason@marel.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Replace most of the can interface's state and error counters
handling with the new can-dev can_change_state() mechanism.
Suggested-by: NAndri Yngvason <andri.yngvason@marel.com>
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Acked-by: NAndri Yngvason <andri.yngvason@marel.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Update all of the can interface's state and error counters before
trying any skb allocation that can actually fail with -ENOMEM.
Suggested-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Acked-by: NAndri Yngvason <andri.yngvason@marel.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

While being in an ERROR_WARNING state, and receiving further
bus error events with error counters still in the ERROR_WARNING
range of 97-127 inclusive, the state handling code erroneously
reverts back to ERROR_ACTIVE.

Per the CAN standard, only revert to ERROR_ACTIVE when the
error counters are less than 96.

Moreover, in certain Kvaser models, the BUS_ERROR flag is
always set along with undefined bits in the M16C status
register. Thus use bitwise operators instead of full equality
for checking that register against bus errors.
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

On some x86 laptops, plugging a Kvaser device again after an
unplug makes the firmware always ignore the very first command.
For such a case, provide some room for retries instead of
completely exiting the driver init code.
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Send expected argument to the URB completion hander: a CAN
netdevice instead of the network interface private context
`kvaser_usb_net_priv'.

This was discovered by having some garbage in the kernel
log in place of the netdevice names: can0 and can1.
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Upon receiving a hardware event with the BUS_RESET flag set,
the driver kills all of its anchored URBs and resets all of
its transmit URB contexts.

Unfortunately it does so under the context of URB completion
handler `kvaser_usb_read_bulk_callback()', which is often
called in an atomic context.

While the device is flooded with many received error packets,
usb_kill_urb() typically sleeps/reschedules till the transfer
request of each killed URB in question completes, leading to
the sleep in atomic bug. [3]

In v2 submission of the original driver patch [1], it was
stated that the URBs kill and tx contexts reset was needed
since we don't receive any tx acknowledgments later and thus
such resources will be locked down forever. Fortunately this
is no longer needed since an earlier bugfix in this patch
series is now applied: all tx URB contexts are reset upon CAN
channel close. [2]

Moreover, a BUS_RESET is now treated _exactly_ like a BUS_OFF
event, which is the recommended handling method advised by
the device manufacturer.

[1] http://article.gmane.org/gmane.linux.network/239442
    http://www.webcitation.org/6Vr2yagAQ

[2] can: kvaser_usb: Reset all URB tx contexts upon channel close
    889b77f7

[3] Stacktrace:

 <IRQ>  [<ffffffff8158de87>] dump_stack+0x45/0x57
 [<ffffffff8158b60c>] __schedule_bug+0x41/0x4f
 [<ffffffff815904b1>] __schedule+0x5f1/0x700
 [<ffffffff8159360a>] ? _raw_spin_unlock_irqrestore+0xa/0x10
 [<ffffffff81590684>] schedule+0x24/0x70
 [<ffffffff8147d0a5>] usb_kill_urb+0x65/0xa0
 [<ffffffff81077970>] ? prepare_to_wait_event+0x110/0x110
 [<ffffffff8147d7d8>] usb_kill_anchored_urbs+0x48/0x80
 [<ffffffffa01f4028>] kvaser_usb_unlink_tx_urbs+0x18/0x50 [kvaser_usb]
 [<ffffffffa01f45d0>] kvaser_usb_rx_error+0xc0/0x400 [kvaser_usb]
 [<ffffffff8108b14a>] ? vprintk_default+0x1a/0x20
 [<ffffffffa01f5241>] kvaser_usb_read_bulk_callback+0x4c1/0x5f0 [kvaser_usb]
 [<ffffffff8147a73e>] __usb_hcd_giveback_urb+0x5e/0xc0
 [<ffffffff8147a8a1>] usb_hcd_giveback_urb+0x41/0x110
 [<ffffffffa0008748>] finish_urb+0x98/0x180 [ohci_hcd]
 [<ffffffff810cd1a7>] ? acct_account_cputime+0x17/0x20
 [<ffffffff81069f65>] ? local_clock+0x15/0x30
 [<ffffffffa000a36b>] ohci_work+0x1fb/0x5a0 [ohci_hcd]
 [<ffffffff814fbb31>] ? process_backlog+0xb1/0x130
 [<ffffffffa000cd5b>] ohci_irq+0xeb/0x270 [ohci_hcd]
 [<ffffffff81479fc1>] usb_hcd_irq+0x21/0x30
 [<ffffffff8108bfd3>] handle_irq_event_percpu+0x43/0x120
 [<ffffffff8108c0ed>] handle_irq_event+0x3d/0x60
 [<ffffffff8108ec84>] handle_fasteoi_irq+0x74/0x110
 [<ffffffff81004dfd>] handle_irq+0x1d/0x30
 [<ffffffff81004727>] do_IRQ+0x57/0x100
 [<ffffffff8159482a>] common_interrupt+0x6a/0x6a
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch removes the unused variable "struct net_device *dev" from the
"struct at91_priv".
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch removes the unused variable "struct net_device *dev" from the
"struct flexcan_priv".
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/dev.c:294:2-3: Unneeded semicolon

 Removes unneeded semicolon.

Generated by: scripts/coccinelle/misc/semicolon.cocci

Cc: Andri Yngvason <andri.yngvason@marel.com>
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Put controller into init mode in network stop to end pending transmissions. The
issue is observed in cases when transmitted frame is not acked.
Signed-off-by: NViktor Babrian <babrian.viktor@renyi.mta.hu>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

In order to be able to move the stats increment from can_bus_off() into
can_change_state(), the increment had to be moved back into code that was using
can_bus_off() but not can_change_state().

As a side-effect, this patch fixes the following bugs:
 * Redundant call to can_bus_off() in c_can.
 * Bus-off counted twice in xilinx_can.
Signed-off-by: NAndri Yngvason <andri.yngvason@marel.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

We should not touch the packet after a netif_rx: it might
get freed behind our back.
Suggested-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Recent Leaf firmware versions (>= 3.1.557) do not allow to send
commands for non-existing channels.  If a command is sent for a
non-existing channel, the firmware crashes.
Reported-by: NChristopher Storah <Christopher.Storah@invetech.com.au>
Signed-off-by: NOlivier Sobrie <olivier@sobrie.be>
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Flooding the Kvaser CAN to USB dongle with multiple reads and
writes in very high frequency (*), closing the CAN channel while
all the transmissions are on (#), opening the device again (@),
then sending a small number of packets would make the driver
enter an almost infinite loop of:

[....]
[15959.853988] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853990] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853991] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853993] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853994] kvaser_usb 4-3:1.0 can0: cannot find free context
[15959.853995] kvaser_usb 4-3:1.0 can0: cannot find free context
[....]

_dragging the whole system down_ in the process due to the
excessive logging output.

Initially, this has caused random panics in the kernel due to a
buggy error recovery path.  That got fixed in an earlier commit.(%)
This patch aims at solving the root cause. -->

16 tx URBs and contexts are allocated per CAN channel per USB
device. Such URBs are protected by:

a) A simple atomic counter, up to a value of MAX_TX_URBS (16)
b) A flag in each URB context, stating if it's free
c) The fact that ndo_start_xmit calls are themselves protected
   by the networking layers higher above

After grabbing one of the tx URBs, if the driver noticed that all
of them are now taken, it stops the netif transmission queue.
Such queue is worken up again only if an acknowedgment was received
from the firmware on one of our earlier-sent frames.

Meanwhile, upon channel close (#), the driver sends a CMD_STOP_CHIP
to the firmware, effectively closing all further communication.  In
the high traffic case, the atomic counter remains at MAX_TX_URBS,
and all the URB contexts remain marked as active.  While opening
the channel again (@), it cannot send any further frames since no
more free tx URB contexts are available.

Reset all tx URB contexts upon CAN channel close.

(*) 50 parallel instances of `cangen0 -g 0 -ix`
(#) `ifconfig can0 down`
(@) `ifconfig can0 up`
(%) "can: kvaser_usb: Don't free packets when tight on URBs"
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Flooding the Kvaser CAN to USB dongle with multiple reads and
writes in high frequency caused seemingly-random panics in the
kernel.

On further inspection, it seems the driver erroneously freed the
to-be-transmitted packet upon getting tight on URBs and returning
NETDEV_TX_BUSY, leading to invalid memory writes and double frees
at a later point in time.

Note:

Finding no more URBs/transmit-contexts and returning NETDEV_TX_BUSY
is a driver bug in and out of itself: it means that our start/stop
queue flow control is broken.

This patch only fixes the (buggy) error handling code; the root
cause shall be fixed in a later commit.
Acked-by: NOlivier Sobrie <olivier@sobrie.be>
Signed-off-by: NAhmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

use of regmap_read() and regmap_write() in c_can_hw_raminit_syscon()
is not safe as the RAMINIT register can be shared between different drivers
at least for TI SoCs.

To make the modification atomic we switch to using regmap_update_bits().

regmap_update_bits() skips writing to the register if it's read content is the
same as what is going to be written. This causes an issue for us when we
need to clear the DONE bit with the initial condition START:0, DONE:1 as
DONE bit must be written with 1 to clear it.

So we defer the clearing of DONE bit to later when we set the START bit.
There we are sure that START bit is changed from 0 to 1 so the write of
1 to already set DONE bit will happen.
Signed-off-by: NRoger Quadros <rogerq@ti.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

During the CAN FD standardization process within the ISO it turned out that
the failure detection capability has to be improved.

The CAN in Automation organization (CiA) defined the already implemented CAN
FD controllers as 'non-ISO' and the upcoming improved CAN FD controllers as
'ISO' compliant. See at http://www.can-cia.com/index.php?id=1937

Finally there will be three types of CAN FD controllers in the future:

1. ISO compliant (fixed)
2. non-ISO compliant (fixed, like the M_CAN IP v3.0.1 in m_can.c)
3. ISO/non-ISO CAN FD controllers (switchable, like the PEAK USB FD)

So the current M_CAN driver for the M_CAN IP v3.0.1 has to expose its non-ISO
implementation by setting the CAN_CTRLMODE_FD_NON_ISO ctrlmode at startup.
As this bit cannot be switched at configuration time CAN_CTRLMODE_FD_NON_ISO
must not be set in ctrlmode_supported of the current M_CAN driver.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

When changing flags in the CAN drivers ctrlmode the provided new content has to
be checked whether the bits are allowed to be changed. The bits that are to be
changed are given as a bitfield in cm->mask. Therefore checking against
cm->flags is wrong as the content can hold any kind of values.

The iproute2 tool sets the bits in cm->mask and cm->flags depending on the
detected command line options. To be robust against bogus user space
applications additionally sanitize the provided flags with the provided mask.

Cc: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Replacing error state change handling with the new mechanism.
Signed-off-by: NAndri Yngvason <andri.yngvason@marel.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Replacing error state change handling with the new mechanism.
Signed-off-by: NAndri Yngvason <andri.yngvason@marel.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Replacing error state change handling with the new mechanism.
Signed-off-by: NAndri Yngvason <andri.yngvason@marel.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The handling of can error states is different between platforms.
This is an attempt to correct that problem.

I've moved this handling into a generic function for changing the
error state. This ensures that error state changes are handled
the same way everywhere (where this function is used).

This new mechanism also adds reverse state transitioning in error
frames, i.e. the user will be notified through the socket interface
when the state goes down.
Signed-off-by: NAndri Yngvason <andri.yngvason@marel.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch enables endian checking by default when running sparse via "make
C=2" for example.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Fix various spelling errors in the comments of the CAN modules.
Signed-off-by: NJeremiah Mahler <jmmahler@gmail.com>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Several can modules in drivers/net/can use a banner[] variable at the
top which defines a string that is used once during init.  This string
is also embedded with KERN_INFO which makes it printk() specific.

Improve the code by eliminating the banner[] variable and moving the
string to where it is printed.  Then switch from printk(KERN_INFO to
pr_info() for the lines that were changed.

This patch is similar to [1] which was applied to net/can.

  [1]: https://lkml.org/lkml/2014/11/22/10Signed-off-by: NJeremiah Mahler <jmmahler@gmail.com>
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch fixes the endianess definition as well as the usage of the
multi-byte fields in the data structures exchanged with the PEAK-System USB
adapters.

By fixing the endianess, this patch also fixes the wrong usage of a 32-bits
local variable for handling the error status 16-bits field, in function
pcan_usb_pro_handle_error().
Signed-off-by: NStephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch sets the correct reverse sequence order to the instructions
set to run, when any failure occurs during the initialization steps.
It also adds the missing unregistration call of the can device if the
failure appears after having been registered.
Signed-off-by: NStephane Grosjean <s.grosjean@peak-system.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patchs fixes a misplaced call to memset() that fills the request
buffer with 0. The problem was with sending PCAN_USBPRO_REQ_FCT
requests, the content set by the caller was thus lost.

With this patch, the memory area is zeroed only when requesting info
from the device.
Signed-off-by: NStephane Grosjean <s.grosjean@peak-system.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Bosch M_CAN is CAN FD capable device. This patch implements the CAN
FD features include up to 64 bytes payload and bitrate switch function.
1) Change the Rx FIFO and Tx Buffer to 64 bytes for support CAN FD
   up to 64 bytes payload. It's backward compatible with old 8 bytes
   normal CAN frame.
2) Allocate can frame or canfd frame based on EDL bit
3) Bitrate Switch function is disabled by default and will be enabled
   according to CANFD_BRS bit in cf->flags.
Acked-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NDong Aisheng <b29396@freescale.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Fix a few error messages.
Signed-off-by: NDong Aisheng <b29396@freescale.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The spec mentions there may be a delay until the value written to INIT can be
read back due to the synchronization mechanism between the two clock domains.
But it does not indicate the exact clock cycles needed. The 5us delay is a
test value and seems ok.

Without the delay, CCCR.CCE bit may fail to be set and then the initialization
fail sometimes when do repeatly up and down.
Signed-off-by: NDong Aisheng <b29396@freescale.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The original code missed to set the cf->can_dlc in the RTR case, so add it.
Signed-off-by: NDong Aisheng <b29396@freescale.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The m_can_get_berr_counter function can sleep and it may be called in napi poll
function. Rework it to fix the following warning.

root@imx6qdlsolo:~# cangen can0 -f -L 12 -D 112233445566778899001122
[ 1846.017565] m_can 20e8000.can can0: entered error warning state
[ 1846.023551] ------------[ cut here ]------------
[ 1846.028216] WARNING: CPU: 0 PID: 560 at kernel/locking/mutex.c:867 mutex_trylock+0x218/0x23c()
[ 1846.036889] DEBUG_LOCKS_WARN_ON(in_interrupt())
[ 1846.041263] Modules linked in:
[ 1846.044594] CPU: 0 PID: 560 Comm: cangen Not tainted 3.17.0-rc4-next-20140915-00010-g032d018-dirty #477
[ 1846.054033] Backtrace:
[ 1846.056557] [<80012448>] (dump_backtrace) from [<80012728>] (show_stack+0x18/0x1c)
[ 1846.064180]  r6:809a07ec r5:809a07ec r4:00000000 r3:00000000
[ 1846.069966] [<80012710>] (show_stack) from [<806c9ee0>] (dump_stack+0x8c/0xa4)
[ 1846.077264] [<806c9e54>] (dump_stack) from [<8002aa78>] (warn_slowpath_common+0x70/0x94)
[ 1846.085403]  r6:806cd1b0 r5:00000009 r4:be1d5c20 r3:be07b0c0
[ 1846.091204] [<8002aa08>] (warn_slowpath_common) from [<8002aad4>] (warn_slowpath_fmt+0x38/0x40)
[ 1846.099951]  r8:8119106c r7:80515aa4 r6:be027000 r5:00000001 r4:809d1df4
[ 1846.106830] [<8002aaa0>] (warn_slowpath_fmt) from [<806cd1b0>] (mutex_trylock+0x218/0x23c)
[ 1846.115141]  r3:80851c88 r2:8084fb74
[ 1846.118804] [<806ccf98>] (mutex_trylock) from [<80515aa4>] (clk_prepare_lock+0x14/0xf4)
[ 1846.126859]  r8:00000040 r7:be1d5cec r6:be027000 r5:be255800 r4:be027000
[ 1846.133737] [<80515a90>] (clk_prepare_lock) from [<80517660>] (clk_prepare+0x14/0x2c)
[ 1846.141583]  r5:be255800 r4:be027000
[ 1846.145272] [<8051764c>] (clk_prepare) from [<8041ff14>] (m_can_get_berr_counter+0x20/0xd4)
[ 1846.153672]  r4:be255800 r3:be07b0c0
[ 1846.157325] [<8041fef4>] (m_can_get_berr_counter) from [<80420428>] (m_can_poll+0x310/0x8fc)
[ 1846.165809]  r7:bd4dc540 r6:00000744 r5:11300000 r4:be255800
[ 1846.171590] [<80420118>] (m_can_poll) from [<8056a468>] (net_rx_action+0xcc/0x1b4)
[ 1846.179204]  r10:00000101 r9:be255ebc r8:00000040 r7:be7c3208 r6:8097c100 r5:be7c3200
[ 1846.187192]  r4:0000012c
[ 1846.189779] [<8056a39c>] (net_rx_action) from [<8002deec>] (__do_softirq+0xfc/0x2c4)
[ 1846.197568]  r10:00000101 r9:8097c088 r8:00000003 r7:8097c080 r6:40000001 r5:8097c08c
[ 1846.205559]  r4:00000020
[ 1846.208144] [<8002ddf0>] (__do_softirq) from [<8002e194>] (do_softirq+0x7c/0x88)
[ 1846.215588]  r10:00000000 r9:bd516a60 r8:be18ce00 r7:00000000 r6:be255800 r5:8056c0ec
[ 1846.223578]  r4:60000093
[ 1846.226163] [<8002e118>] (do_softirq) from [<8002e288>] (__local_bh_enable_ip+0xe8/0x10c)
[ 1846.234386]  r4:00000200 r3:be1d4000
[ 1846.238036] [<8002e1a0>] (__local_bh_enable_ip) from [<8056c108>] (__dev_queue_xmit+0x314/0x6b0)
[ 1846.246868]  r6:be255800 r5:bd516a00 r4:00000000 r3:be07b0c0
[ 1846.252645] [<8056bdf4>] (__dev_queue_xmit) from [<8056c4b8>] (dev_queue_xmit+0x14/0x18)
Signed-off-by: NDong Aisheng <b29396@freescale.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The M_CAN message RAM is usually equipped with a parity or ECC functionality.
But RAM cells suffer a hardware reset and can therefore hold arbitrary content
at startup - including parity and/or ECC bits.

To prevent the M_CAN controller detecting checksum errors when reading
potentially uninitialized TX message RAM content to transmit CAN frames the TX
message RAM has to be written with (any kind of) initial data.
Signed-off-by: NDong Aisheng <b29396@freescale.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

m_can uses io memory which makes it not compilable on architectures
without HAS_IOMEM such as UML:

drivers/built-in.o: In function `m_can_plat_probe':
m_can.c:(.text+0x218cc5): undefined reference to `devm_ioremap_resource'
m_can.c:(.text+0x218df9): undefined reference to `devm_ioremap'
Signed-off-by: NDavid Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Use common can_change_mtu function.
Signed-off-by: NDong Aisheng <b29396@freescale.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Use common can_change_mtu function.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>