This patch gives the member of flexcan_priv holding mailboxes a sensible name,
by renaming from "cantxfg" to "mb":

    struct flexcan_priv::cantxfg -> struct flexcan_priv::mb
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch renames the pointer to the mmio address space from "base" to "regs"
and changes the type from "void __iomem *" to "struct flexcan_regs __iomem *".
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch renames the "features" member of struct flexcan_devtype_data to
"quirks". The corresponding defines are renamed too, to reflect what they
actually do.

    FLEXCAN_HAS_V10_FEATURES      -> FLEXCAN_QUIRK_DISABLE_RXFG
    FLEXCAN_HAS_BROKEN_ERR_STATE  -> FLEXCAN_QUIRK_BROKEN_ERR_STATE
    FLEXCAN_HAS_MECR_FEATURES     -> FLEXCAN_QUIRK_DISABLE_MECR
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch changes the order the individual bits of the mcr register in
flexcan_chip_start() are or'ed together to match the datasheet. The inline
documentation is adjusted accordingly.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch removes unused header files from the flexcan driver.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch fixes up the coding style to make checkpatch happier. Some typos are
also fixed.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This message isn't really helpful for the general reader of the kernel
logs, so should not be printed with info level. All other register
programming outputs in the flexcan driver already use the debug level.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

There is no guarantee that the skb is in the same state after calling
net_receive_skb() or netif_rx(). It might be freed or reused. Not really
harmful as its a read access, except you turn on the proper debugging options
which catch a use after free.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch replaces a open coded variant of a "mailbox code" definition by an
existing define, improves code readability.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This is done to mach the abbreviationin of the register in the datasheets.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch adds a short documentation snippet about the mailbox organization as
it's regularly not correct in freescale's datasheets.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Flexcan V10 and newer are able to receive RTR frames in a MB. Older versions
are not. Those should use flexcan in FIFO mode.
Signed-off-by: NDavid Jander <david@protonic.nl>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Return EPROBE_DEFER if Regulator returns EPROBE_DEFER

If the Flexcan driver is built into kernel and a regulator is used to
enable the CAN transceiver, the Flexcan driver may not use the regulator.

When initializing the Flexcan device with a regulator defined in the device
tree, but not initialized, the regulator subsystem returns EPROBE_DEFER, hence
the Flexcan init fails.

The solution for this is to return EPROBE_DEFER if regulator is not initialized
and wait until the regulator is initialized.
Signed-off-by: NAndreas Werner <kernel@andy89.org>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Making sure that the bus-off state gets passed to can_change_state().
Signed-off-by: NAndri Yngvason <andri.yngvason@marel.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 flexcan_priv".
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>

A platform_driver does not need to set an owner, it will be populated by the
driver core.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This patch increases the mask in the FLEXCAN_MCR_MAXMB() to 7 bits as in the
newer flexcan cores the MAXMB field is 7 bits wide.
Reported-by: NDavid Jander <david@protonic.nl>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

After sending a RTR frame the TX mailbox becomes a RX_EMPTY mailbox. To avoid
side effects when the RX-FIFO is full, this patch puts the TX mailbox into
TX_INACTIVE mode in the transmission complete interrupt handler. This, of
course, leaves a race window between the actual completion of the transmission
and the handling of tx-complete interrupt. However this is the best we can do
without busy polling the tx complete interrupt.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch implements the workaround mentioned in ERR005829:

    ERR005829: FlexCAN: FlexCAN does not transmit a message that is enabled to
    be transmitted in a specific moment during the arbitration process.

Workaround: The workaround consists of two extra steps after setting up a
message for transmission:

Step 8: Reserve the first valid mailbox as an inactive mailbox (CODE=0b1000).
If RX FIFO is disabled, this mailbox must be message buffer 0. Otherwise, the
first valid mailbox can be found using the "RX FIFO filters" table in the
FlexCAN chapter of the chip reference manual.

Step 9: Write twice INACTIVE code (0b1000) into the first valid mailbox.
Signed-off-by: NDavid Jander <david@protonic.nl>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Apparently mailboxes may contain random data at startup, causing some of them
being prepared for message reception. This causes overruns being missed or even
confusing the IRQ check for trasmitted messages, increasing the transmit
counter instead of the error counter.

This patch initializes all mailboxes after the FIFO as RX_INACTIVE.
Signed-off-by: NDavid Jander <david@protonic.nl>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch fixes the initialization of the TX mailbox. It is now correctly
initialized as TX_INACTIVE not RX_EMPTY.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Apparently can_restart() runs from a (timer-) interrupt and can call
flexcan_chip_[en|dis]able(), so avoid using usleep_range()
Signed-off-by: NDavid Jander <david@protonic.nl>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Once the CAN-bus is open and a packet is sent, the controller switches
into the PASSIVE state. Once the BUS is closed again it goes the back
err-warning. The TX error counter goes 0 -> 0x80 -> 0x7f.
This patch makes sure that the user learns about this state chang
(CAN_STATE_ERROR_WARNING => CAN_STATE_ERROR_PASSIVE)
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NMatthias Klein <matthias.klein@optimeas.de>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

In case we don't have FLEXCAN_HAS_BROKEN_ERR_STATE and the user set
CAN_CTRLMODE_BERR_REPORTING once it can not be unset again until reboot.
So in case neither hardware nor user wants the error interrupt disable
the bit.
Signed-off-by: NAlexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

Extend FlexCAN driver to support Vybrid. Vybrids variant of the IP
has ECC support which is controlled through the memory error
control register (MECR). There is also an errata which leads to
false positive error detections (ID e5295). This patch disables
the memory error detection completely.
Signed-off-by: NStefan Agner <stefan@agner.ch>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The funcion flexcan_get_berr_counter() may be called from userspace even if the
interface is down, this the clocks are disabled. This patch switches on the
clocks before accessing the ecr register.
Reported-by: NAshutosh Singh <ashuleapyear@gmail.com>
Signed-off-by: NStefan Agner <stefan@agner.ch>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

CAN interfaces only support MTU values of 16 (CAN 2.0) and 72 (CAN FD).
Setting the MTU to other values is pointless but it does not really hurt.
With the introduction of the CAN FD support in drivers/net/can a new
function to switch the MTU for CAN FD has been introduced.

This patch makes use of this can_change_mtu() function to check for correct
MTU settings also in legacy CAN (2.0) devices.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch replaces an open coded pdev->id_entry by platform_get_device_id().
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch removes #ifdef CONFIG_PM_SLEEP to improve compile coverage.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch moves the soft reset into a seperate function.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch adds the missing netif_napi_del() to the flexcan_remove() function.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch factors out freeze and unfreeze of the CAN core into seperate
functions. Experiments have shown that the transition from and to freeze mode
may take several microseconds, especially the time entering the freeze mode
depends on the current bitrate.

This patch adds a while loop which polls the Freeze Mode ACK bit (FRZ_ACK) that
indicates a successfull mode change. If the function runs into a timeout a
error value is returned.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

This patch moves the transceiver enable and disable into seperate functions,
where the NULL pointer check is hidden.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

In flexcan_chip_enable() and flexcan_chip_disable() fixed delays are used.
Experiments have shown that the transition from and to low power mode may take
several microseconds.

This patch adds a while loop which polls the Low Power Mode ACK bit (LPM_ACK)
that indicates a successfull mode change. If the function runs into a timeout a
error value is returned.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

If flexcan_chip_start() in flexcan_open() fails, the interrupt is not freed,
this patch adds the missing cleanup.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

When shutting down the CAN interface (ifconfig canX down) during high CAN bus
loads, the CAN core might hang and freeze the whole CPU.

This patch fixes the shutdown sequence by first disabling the CAN core then
disabling all interrupts.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

There is no reason to disallow building the driver on big-endian ARM kernels.
Furthermore, the current behavior is actually broken on little-endian PowerPC
as well.

The choice of register accessor functions must purely depend on the CPU
architecture, not which endianess the CPU is running on. Note that we nowadays
allow both big-endian ARM and little-endian PowerPC kernels.

With this patch applied, we will do the right thing in all four combinations.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The flexcan IP core uses the peripheral clock ("per") as basic clock for the
bit timing calculation. However the driver uses the the wrong clock ("ipg").
This leads to wrong bit rates if the rates on both clock are different.

This patch fixes the problem by using the correct clock for the bit rate
calculation.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

The current implemetation of of_match_device() relies that the of_device_id
table in the driver is sorted from most specific to least specific compatible.

Without this patch the mx28 is detected as the less specific p1010. This leads
to a p1010 specific workaround is activated on the mx28, which is not needed.

Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>