can: dev: fix skb drop check

In commit a6d190f8c767 ("can: skb: drop tx skb if in listen only
mode") the priv->ctrlmode element is read even on virtual CAN
interfaces that do not create the struct can_priv at startup. This
out-of-bounds read may lead to CAN frame drops for virtual CAN
interfaces like vcan and vxcan.

This patch mainly reverts the original commit and adds a new helper
for CAN interface drivers that provide the required information in
struct can_priv.

Fixes: a6d190f8c767 ("can: skb: drop tx skb if in listen only mode")
Reported-by: Dariusz Stojaczyk <Dariusz.Stojaczyk@opensynergy.com>
Cc: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Cc: Max Staudt <max@enpas.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20221102095431.36831-1-socketcan@hartkopp.net
Cc: stable@vger.kernel.org # 6.0.x
[mkl: patch pch_can, too]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: mcp251x_can_probe(): add missing unregister_candev() in error path

In mcp251x_can_probe(), if mcp251x_gpio_setup() fails, it forgets to
unregister the CAN device.

Fix this by unregistering can device in mcp251x_can_probe().

Fixes: 2d52dabbef60 ("can: mcp251x: add GPIO support")
Signed-off-by: Dongliang Mu <dzm91@hust.edu.cn>
Link: https://lore.kernel.org/all/20221024090256.717236-1-dzm91@hust.edu.cn
[mkl: adjust label]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Fix race condition on receive interrupt

The mcp251x driver uses both receiving mailboxes of the CAN controller
chips. For retrieving the CAN frames from the controller via SPI, it checks
once per interrupt which mailboxes have been filled and will retrieve the
messages accordingly.

This introduces a race condition, as another CAN frame can enter mailbox 1
while mailbox 0 is emptied. If now another CAN frame enters mailbox 0 until
the interrupt handler is called next, mailbox 0 is emptied before
mailbox 1, leading to out-of-order CAN frames in the network device.

This is fixed by checking the interrupt flags once again after freeing
mailbox 0, to correctly also empty mailbox 1 before leaving the handler.

For reproducing the bug I created the following setup:
- Two CAN devices, one Raspberry Pi with MCP2515, the other can be any.
- Setup CAN to 1 MHz
- Spam bursts of 5 CAN-messages with increasing CAN-ids
- Continue sending the bursts while sleeping a second between the bursts
- Check on the RPi whether the received messages have increasing CAN-ids
- Without this patch, every burst of messages will contain a flipped pair

v3: https://lore.kernel.org/all/20220804075914.67569-1-sebastian.wuerl@ororatech.com
v2: https://lore.kernel.org/all/20220804064803.63157-1-sebastian.wuerl@ororatech.com
v1: https://lore.kernel.org/all/20220803153300.58732-1-sebastian.wuerl@ororatech.com

Fixes: bf66f3736a94 ("can: mcp251x: Move to threaded interrupts instead of workqueues.")
Signed-off-by: Sebastian Würl <sebastian.wuerl@ororatech.com>
Link: https://lore.kernel.org/all/20220804081411.68567-1-sebastian.wuerl@ororatech.com
[mkl: reduce scope of intf1, eflag1]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: tree-wide: advertise software timestamping capabilities

Currently, some CAN drivers support hardware timestamping, some do
not. But userland has no method to query which features are supported
(aside maybe of getting RX messages and observe whether or not
hardware timestamps stay at zero).

The canonical way for a network driver to advertised what kind of
timestamping it supports is to implement ethtool_ops::get_ts_info().

This patch only targets the CAN drivers which *do not* support
hardware timestamping. For each of those CAN drivers, implement the
get_ts_info() using the generic ethtool_op_get_ts_info().

This way, userland can do:

| $ ethtool --show-time-stamping canX

to confirm the device timestamping capacities.

N.B. the drivers which support hardware timestamping will be migrated
in separate patches.

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20220727101641.198847-6-mailhol.vincent@wanadoo.fr
[mkl: mscan: add missing mscan_ethtool_ops]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: can-dev: remove obsolete CAN LED support

Since commit 30f3b42147ba6f ("can: mark led trigger as broken") the
CAN specific LED support was disabled and marked as BROKEN. As the
common LED support with CONFIG_LEDS_TRIGGER_NETDEV should do this work
now the code can be removed as preparation for a CAN netdevice Kconfig
rework.

Link: https://lore.kernel.org/all/20220518154527.29046-1-socketcan@hartkopp.net
Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
[mkl: remove led.h from MAINTAINERS]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: Use netif_rx().

Since commit
baebdf48c3600 ("net: dev: Makes sure netif_rx() can be invoked in any context.")

the function netif_rx() can be used in preemptible/thread context as
well as in interrupt context.

Use netif_rx().

Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: linux-can@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

spi: make remove callback a void function

The value returned by an spi driver's remove function is mostly ignored.
(Only an error message is printed if the value is non-zero that the
error is ignored.)

So change the prototype of the remove function to return no value. This
way driver authors are not tempted to assume that passing an error to
the upper layer is a good idea. All drivers are adapted accordingly.
There is no intended change of behaviour, all callbacks were prepared to
return 0 before.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Claudius Heine <ch@denx.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Acked-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Acked-by: Łukasz Stelmach <l.stelmach@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220123175201.34839-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

can: do not increase tx_bytes statistics for RTR frames

The actual payload length of the CAN Remote Transmission Request (RTR)
frames is always 0, i.e. no payload is transmitted on the wire.
However, those RTR frames still use the DLC to indicate the length of
the requested frame.

As such, net_device_stats::tx_bytes should not be increased when
sending RTR frames.

The function can_get_echo_skb() already returns the correct length,
even for RTR frames (c.f. [1]). However, for historical reasons, the
drivers do not use can_get_echo_skb()'s return value and instead, most
of them store a temporary length (or dlc) in some local structure or
array. Using the return value of can_get_echo_skb() solves the
issue. After doing this, such length/dlc fields become unused and so
this patch does the adequate cleaning when needed.

This patch fixes all the CAN drivers.

Finally, can_get_echo_skb() is decorated with the __must_check
attribute in order to force future drivers to correctly use its return
value (else the compiler would emit a warning).

[1] commit ed3320cec279 ("can: dev: __can_get_echo_skb():
fix real payload length return value for RTR frames")

Link: https://lore.kernel.org/all/20211207121531.42941-6-mailhol.vincent@wanadoo.fr
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: Yasushi SHOJI <yashi@spacecubics.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Stephane Grosjean <s.grosjean@peak-system.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Tested-by: Jimmy Assarsson <extja@kvaser.com> # kvaser
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2
Tested-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2
[mkl: add conversion for grcan]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: do not increase rx_bytes statistics for RTR frames

The actual payload length of the CAN Remote Transmission Request (RTR)
frames is always 0, i.e. no payload is transmitted on the wire.
However, those RTR frames still use the DLC to indicate the length of
the requested frame.

As such, net_device_stats::rx_bytes should not be increased for the
RTR frames.

This patch fixes all the CAN drivers.

Link: https://lore.kernel.org/all/20211207121531.42941-5-mailhol.vincent@wanadoo.fr
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Chandrasekar Ramakrishnan <rcsekar@samsung.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: Yasushi SHOJI <yashi@spacecubics.com>
Cc: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Cc: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Stephane Grosjean <s.grosjean@peak-system.com>
Tested-by: Jimmy Assarsson <extja@kvaser.com> # kvaser
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2
Tested-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: do not copy the payload of RTR frames

The actual payload length of the CAN Remote Transmission Request (RTR)
frames is always 0, i.e. no payload is transmitted on the wire.
However, those RTR frames still use the DLC to indicate the length of
the requested frame.

For this reason, it is incorrect to copy the payload of RTR frames
(the payload buffer would only contain garbage data). This patch
encapsulates the payload copy in a check toward the RTR flag.

Link: https://lore.kernel.org/all/20211207121531.42941-4-mailhol.vincent@wanadoo.fr
Cc: Yasushi SHOJI <yashi@spacecubics.com>
Tested-by: Yasushi SHOJI <yashi@spacecubics.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: mcp251x_gpio_setup(): Get rid of duplicate of_node assignment

GPIO library does copy the of_node from the parent device of the GPIO
chip, there is no need to repeat this in the individual drivers.
Remove assignment here.

For the details one may look into the of_gpio_dev_init()
implementation.

Link: https://lore.kernel.org/all/20211202205855.76946-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: mcp251x_can_probe(): silence clang warning

This patch silences the following clang warning:

| drivers/net/can/spi/mcp251x.c:1333:17: warning: cast to smaller integer type
| 'enum mcp251x_model' from 'const void *' [-Wvoid-pointer-to-enum-cast]
| priv->model = (enum mcp251x_model)match;
| ^~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 8de29a5c34a5 ("can: mcp251x: Make use of device property API")
Link: https://lore.kernel.org/r/20210504200520.1179635-2-mkl@pengutronix.de
Reported-by: kernel test robot <lkp@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: fix resume from sleep before interface was brought up

Since 8ce8c0abcba3 the driver queues work via priv->restart_work when
resuming after suspend, even when the interface was not previously
enabled. This causes a null dereference error as the workqueue is only
allocated and initialized in mcp251x_open().

To fix this we move the workqueue init to mcp251x_can_probe() as there
is no reason to do it later and repeat it whenever mcp251x_open() is
called.

Fixes: 8ce8c0abcba3 ("can: mcp251x: only reset hardware as required")
Link: https://lore.kernel.org/r/17d5d714-b468-482f-f37a-482e3d6df84e@kontron.de
Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[mkl: fix error handling in mcp251x_stop()]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: dev: can_free_echo_skb(): extend to return can frame length

In order to implement byte queue limits (bql) in CAN drivers, the
length of the CAN frame needs to be passed into the networking stack
even if the transmission failed for some reason.

To avoid to calculate this length twice, extend can_free_echo_skb() to
return that value. Convert all users of this function, too.

This patch is the natural extension of commit:

| 9420e1d495e2 ("can: dev: can_get_echo_skb(): extend to return can
| frame length")

Link: https://lore.kernel.org/r/20210319142700.305648-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: fix support for half duplex SPI host controllers

Some SPI host controllers do not support full-duplex SPI transfers.

The function mcp251x_spi_trans() does a full duplex transfer. It is
used in several places in the driver, where a TX half duplex transfer
is sufficient.

To fix support for half duplex SPI host controllers, this patch
introduces a new function mcp251x_spi_write() and changes all callers
that do a TX half duplex transfer to use mcp251x_spi_write().

Fixes: e0e25001d088 ("can: mcp251x: add support for half duplex controllers")
Link: https://lore.kernel.org/r/20210330100246.1074375-1-mkl@pengutronix.de
Cc: Tim Harvey <tharvey@gateworks.com>
Tested-By: Tim Harvey <tharvey@gateworks.com>
Reported-by: Gerhard Bertelsmann <info@gerhard-bertelsmann.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: dev: can_get_echo_skb(): extend to return can frame length

In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.

To avoid to calculate this length twice, extend can_get_echo_skb() to return
that value. Convert all users of this function, too.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-14-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: dev: can_put_echo_skb(): extend to handle frame_len

Add a frame_len argument to can_put_echo_skb() which is used to save length of
the CAN frame into field frame_len of struct can_skb_priv so that it can be
later used after transmission completion. Convert all users of this function,
too.

Drivers which implement BQL call can_put_echo_skb() with the output of
can_skb_get_frame_len(skb) and drivers which do not simply pass zero as an
input (in the same way that NULL would be given to can_get_echo_skb()). This
way, we have a nice symmetry between the two echo functions.

Link: https://lore.kernel.org/r/20210111061335.39983-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-13-mkl@pengutronix.de
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>

can: replace can_dlc as variable/element for payload length

The naming of can_dlc as element of struct can_frame and also as variable
name is misleading as it claims to be a 'data length CODE' but in reality
it always was a plain data length.

With the indroduction of a new 'len' element in struct can_frame we can now
remove can_dlc as name and make clear which of the former uses was a plain
length (-> 'len') or a data length code (-> 'dlc') value.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201120100444.3199-1-socketcan@hartkopp.net
[mkl: gs_usb: keep struct gs_host_frame::can_dlc as is]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: rename get_can_dlc() macro with can_cc_dlc2len()

The get_can_dlc() macro is used to ensure the payload length information of
the Classical CAN frame to be max 8 bytes (the CAN_MAX_DLEN).

Rename the macro and use the correct constant in preparation of the len/dlc
cleanup for Classical CAN frames.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-3-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: add support for half duplex controllers

Some SPI host controllers do not support full-duplex SPI and are
marked as such via the SPI_CONTROLLER_HALF_DUPLEX controller flag.

For such controllers use half duplex transactions but retain full
duplex transactions for the controllers that can handle those.

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Link: https://lore.kernel.org/r/1595516275-1179-1-git-send-email-tharvey@gateworks.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Use readx_poll_timeout() helper

We may use special helper macro to poll IO till condition or timeout occurs.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217161038.25009-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: add GPIO support

The mcp251x variants feature 3 general purpose digital inputs and 2
outputs. With this patch they are accessible through the gpio framework.

Signed-off-by: Timo Schlüßler <schluessler@krause.de>
Tested-by: Timo Schlüßler <schluessler@krause.de>
Link: https://lore.kernel.org/r/20200915223527.1417033-28-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: sort include files alphabetically

This patch sorts the include files alphabetically.

Link: https://lore.kernel.org/r/20200915223527.1417033-27-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

can: mcp251x: only reset hardware as required

This prevents unwanted glitches on the outputs when changing the link
state of the can interface or when resuming from suspend. Only if the
device is powered off during suspend it needs to be resetted as required
by the specs.

Signed-off-by: Timo Schlüßler <schluessler@krause.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: add mcp251x_write_2regs() and make use of it

This patch introduces the function mcp251x_write_2regs() to write two
registers with one SPI transfer and converts the disabling of pending
interrupts in mcp251x_stop() to it.

Signed-off-by: Timo Schlüßler <schluessler@krause.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: get rid of legacy platform data

Instead of using legacy platform data, switch to use device properties.
For clock frequency we are using well established clock-frequency property.

Users, two for now, are also converted here.

Cc: Daniel Mack <daniel@zonque.org>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: mcp251x_restart_work_handler(): Fix potential force_quit race condition

In mcp251x_restart_work_handler() the variable to stop the interrupt
handler (priv->force_quit) is reset after the chip is restarted and thus
a interrupt might occur.

This patch fixes the potential race condition by resetting force_quit
before enabling interrupts.

Signed-off-by: Timo Schlüßler <schluessler@krause.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Call wrapper instead of regulator_disable()

There is no need to check for regulator presence in the ->suspend()
since a wrapper does it for us. Due to this we may unconditionally set
AFTER_SUSPEND_POWER flag.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Make use of device property API

Make use of device property API in this driver so that both OF based
system and ACPI based system can use this driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Use devm_clk_get_optional() to get the input clock

Simplify the code which fetches the input clock by using
devm_clk_get_optional(). This comes with a small functional change: previously
all errors were ignored when platform data is present. Now all errors are
treated as errors. If no input clock is present devm_clk_get_optional() will
return NULL instead of an error which matches the behavior of the old code.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: remove deprecated board file setup example

In the pre device-tree ARM aera there were board files that configured
the system (instead of a device tree). A "struct spi_board_info" was
used to describe the SPI bus.

As new systems should be described via device trees, this patch removes
the board setup example from the driver. The "struct
mcp251x_platform_data" cannot be removed completely, as there are still
some in-tree users of this file.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: Delete unnecessary checks before the macro call “dev_kfree_skb”

The dev_kfree_skb() function performs also input parameter validation.
Thus the test around the shown calls is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

can: mcp251x: remove custom DMA mapped buffer

There is no need to duplicate what SPI core already does, i.e. mapping buffers
for DMA capable transfers. This patch removes all related pices of code.

Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Use DT-supplied interrupt flags

The MCP2515 datasheet clearly describes a level-triggered interrupt pin.
Therefore the receiving interrupt controller must also be configured for
level-triggered operation otherwise there is a danger of a missed
interrupt condition blocking all subsequent interrupts. The ONESHOT
flag ensures that the interrupt is masked until the threaded interrupt
handler exits.

Rather than change the flags globally (they must have worked for at
least one user), keep the old behavior for for non DT devices. DT based
devices specify the flags in their corresonding DT node.

See: https://github.com/raspberrypi/linux/issues/2175
https://github.com/raspberrypi/linux/issues/2263

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Use dev_name() during request_threaded_irq()

Passing driver name as name during request_threaded_irq() results in all
CAN IRQs have same name. This does not help much to easily identify which
IRQ belongs to which CAN instance. Therefore pass dev_name() during
request_threaded_irq() so that better identifiable name is listed for
CAN devices in cat /proc/interrupts output.

Output of cat /proc/interrupts
Before this patch:
253: 2 gpio-mxc 13 Edge mcp251x
259: 2 gpio-mxc 19 Edge mcp251x
After this patch:
253: 2 gpio-mxc 13 Edge spi1.1
259: 2 gpio-mxc 19 Edge spi1.2

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: mcp251x_hw_reset(): allow more time after a reset

Some boards take longer than 5ms to power up after a reset, so allow
some retries attempts before giving up.

Fixes: ff06d611a31c ("can: mcp251x: Improve mcp251x_hw_reset()")
Cc: linux-stable <stable@vger.kernel.org>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: use u8 instead of uint8_t

This patch changes all the uint8_t in the arguments in several function
to u8.

Acked-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: fix print formating strings

This patch fixes the print format strings in the driver.

Acked-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: avoid long lines

This patch fixes long lines in the driver.

Acked-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: remove unnecessary blank lines

This patch removes unnecessary blank lines, so that checkpatch doesn't
complain anymore.

Acked-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: convert block comments to network style comments

This patch converts all block comments to network subsystem style block
comments.

Acked-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This patch fixes the following warnings:

drivers/net/can/peak_canfd/peak_pciefd_main.c:668:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/spi/mcp251x.c:875:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/usb/peak_usb/pcan_usb.c:422:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/at91_can.c:895:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/at91_can.c:953:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/usb/peak_usb/pcan_usb.c: In function ‘pcan_usb_decode_error’:
drivers/net/can/usb/peak_usb/pcan_usb.c:422:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (n & PCAN_USB_ERROR_BUS_LIGHT) {
^
drivers/net/can/usb/peak_usb/pcan_usb.c:428:2: note: here
case CAN_STATE_ERROR_WARNING:
^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.

Notice that in some cases spelling mistakes were fixed.
In other cases, the /* fall through */ comment is placed
at the bottom of the case statement, which is what GCC
is expecting to find.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

can: mcp251x: add error check when wq alloc failed

add error check when workqueue alloc failed, and remove redundant code
to make it clear.

Fixes: e0000163e30e ("can: Driver for the Microchip MCP251x SPI CAN controllers")
Signed-off-by: Weitao Hou <houweitaoo@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mark expected switch fall-throughs

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This patch fixes the following warnings:

drivers/net/can/peak_canfd/peak_pciefd_main.c:668:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/spi/mcp251x.c:875:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/usb/peak_usb/pcan_usb.c:422:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/at91_can.c:895:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/at91_can.c:953:15: warning: this statement may fall through [-Wimplicit-fallthrough=]
drivers/net/can/usb/peak_usb/pcan_usb.c: In function ‘pcan_usb_decode_error’:
drivers/net/can/usb/peak_usb/pcan_usb.c:422:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (n & PCAN_USB_ERROR_BUS_LIGHT) {
^
drivers/net/can/usb/peak_usb/pcan_usb.c:428:2: note: here
case CAN_STATE_ERROR_WARNING:
^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.

Notice that in some cases spelling mistakes were fixed.
In other cases, the /* fall through */ comment is placed
at the bottom of the case statement, which is what GCC
is expecting to find.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> # for the at91_can.c
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: add support for mcp25625

Fully compatible with mcp2515, the mcp25625 have integrated transceiver.

This patch adds support for the mcp25625 to the existing mcp251x driver.

Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 344

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the version 2 of the gnu general public
license as published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 15 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000437.427740574@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net: Use octal not symbolic permissions

Prefer the direct use of octal for permissions.

Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.

Miscellanea:

o Whitespace neatening around these conversions.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

can: mcp251x: mcp251x_setup(): remove unused parameter "struct mcp251x_priv *priv"

The 2nd parameter of mcp251x_setup() "struct mcp251x_priv *priv" is not
used, so remove it.

Suggested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: add message about sucessful/unsuccessful probe

Silent ignorance of errors during probe procedure is a bad thing, this
patch fixes it. Extra message added for hardware initialization
failure. Such common issues are mostly caused by wrong wiring. Message
about success added as well, it should be useful to debug new hardware
configuration, especially in case of several CAN buses.

Signed-off-by: Ed Spiridonov <edo.rus@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Replace create_freezable_workqueue with alloc_workqueue

Replace scheduled to be removed create_freezable_workqueue with
alloc_workqueue.

priv->wq should be explicitly set as freezable to ensure it is frozen
in the suspend sequence and work items are drained so that no new work
item starts execution until thawed. Thus, use of WQ_FREEZABLE flag
here is required.

WQ_MEM_RECLAIM flag has been set here to ensure forward progress
regardless of memory pressure.

The order of execution is not important so set @max_active as 0.

Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: avoid write to error flag register if it's unnecessary

Only two bits (RX0OVR and RX1OVR) are writable in EFLG, write is useless
if these bits aren't set.

Signed-off-by: Ed Spiridonov <edo.rus@gmail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

spi: Drop owner assignment from spi_drivers

An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

can: mcp251x: get regulators optionally

The regulators power and transceiver are optional. If those are not
present, the pointer (or error pointer) is correctly handled by the
driver, hence we can use devm_regulator_get_optional safely, which
avoids regulators getting created.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: fix resume when device is down

If a valid power regulator or a dummy regulator is used (which
happens to be the case when no regulator is specified), restart_work
is queued no matter whether the device was running or not at suspend
time. Since work queues get initialized in the ndo_open callback,
resuming leads to a NULL pointer exception.

Reverse exactly the steps executed at suspend time:
- Enable the power regulator in any case
- Enable the transceiver regulator if the device was running, even in
case we have a power regulator
- Queue restart_work only in case the device was running

Fixes: bf66f3736a94 ("can: mcp251x: Move to threaded interrupts instead of workqueues.")
Signed-off-by: Stefan Agner <stefan@agner.ch>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: use correct register address for acceptance filters

This patch corrects addresses of acceptance filters. These registers are not in
use, but values should be correct. Tested with MCP2515 and am3352 and also
checked datasheets for MCP2515 and MCP2510.

Signed-off-by: Tomas Krcka <tomas.krcka@nkgroup.cz>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: move can_stats.bus_off++ from can_bus_off into can_change_state

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: Andri Yngvason <andri.yngvason@marel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: Use dmam_alloc_coherent

This patch moves the data allocated using dma_alloc_coherent to the
corresponding managed interface and does away with the calls to free the
allocated memory in the probe and remove functions.

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: mcp251x: fix coccinelle warnings

drivers/net/can/spi/mcp251x.c:953:7-27: ERROR: Threaded IRQ with no primary handler requested without IRQF_ONESHOT

Make sure threaded IRQs without a primary handler are always request with
IRQF_ONESHOT

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

CC: Stefano Babic <sbabic@denx.de>
CC: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: move SPI drivers into a separate directory

Create a directory for all CAN drivers using SPI and move mcp251x driver there.

Signed-off-by: Stefano Babic <sbabic@denx.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>