can: m_can: allow keeping the transceiver running in suspend

Add a flag to the device class structure that leaves the chip in a
running state with rx interrupt enabled, so that an m_can device driver
can configure and use the interrupt as a wakeup source.

Signed-off-by: Martin Hundebøll <martin@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: Move hrtimer init to m_can_class_register

The hrtimer_init() is called in m_can_plat_probe() and the hrtimer
function is set in m_can_class_register(). For readability it is better
to keep these two together in m_can_class_register().

Cc: Judith Mendez <jm@ti.com>
Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/all/20240207093220.2681425-3-msp@baylibre.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: Add hrtimer to generate software interrupt

Introduce timer polling method to MCAN since some SoCs may not
have M_CAN interrupt routed to A53 Linux and do not have
interrupt property in device tree M_CAN node.

On AM62x SoC, MCANs on MCU domain do not have hardware interrupt
routed to A53 Linux, instead they will use timer polling method.

Add an hrtimer to MCAN class device. Each MCAN will have its own
hrtimer instantiated if there is no hardware interrupt found in
device tree M_CAN node. The timer will generate a software
interrupt every 1 ms. In hrtimer callback, we check if there is
a transaction pending by reading a register, then process by
calling the isr if there is.

Tested-by: Hiago De Franco <hiago.franco@toradex.com> # Toradex Verdin AM62
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Judith Mendez <jm@ti.com>
Link: https://lore.kernel.org/all/20230707204714.62964-3-jm@ti.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart from
emitting a warning) and this typically results in resource leaks. To improve
here there is a quest to make the remove callback return void. In the first
step of this quest all drivers are converted to .remove_new() which already
returns void. Eventually after all drivers are converted, .remove_new() is
renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230512212725.143824-12-u.kleine-koenig@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: Call the RAM init directly from m_can_chip_config

When we try to access the mcan message ram addresses during the probe,
hclk is gated by any other drivers or disabled, because of that probe
gets failed.

Move the mram init functionality to mcan chip config called by
m_can_start from mcan open function, by that time clocks are
enabled.

Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Vivek Yadav <vivek.2311@samsung.com>
Link: https://lore.kernel.org/all/20221207100632.96200-2-vivek.2311@samsung.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: sort header inclusion alphabetically

Sort header inclusion alphabetically.

Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Vivek Yadav <vivek.2311@samsung.com>
Link: https://lore.kernel.org/all/20221104051617.21173-1-vivek.2311@samsung.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: fix iomap_read_fifo() and iomap_write_fifo()

The read and writes from the fifo are from a buffer, with various
fields and data at predefined offsets. So, they should not be done to
the same address(or port) in case of val_count greater than 1.
Therefore, fix this by using iowrite32()/ioread32() instead of
ioread32_rep()/iowrite32_rep().

Also, the write into FIFO must be performed with an offset from the
message ram base address. Therefore, fix the base address to
mram_base.

Fixes: e39381770ec9 ("can: m_can: Disable IRQs on FIFO bus errors")
Link: https://lore.kernel.org/all/20210920123344.2320-1-a-govindraju@ti.com
Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: Disable IRQs on FIFO bus errors

If FIFO reads or writes fail due to the underlying regmap (e.g., SPI)
I/O, propagate that up to the m_can driver, log an error, and disable
interrupts, similar to the mcp251xfd driver.

While reworking the FIFO functions to add this error handling,
add support for bulk reads and writes of multiple registers.

Link: https://lore.kernel.org/r/20210817050853.14875-2-matt@bitbashing.io
Signed-off-by: Matt Kline <matt@bitbashing.io>
[mkl: re-wrap long lines, remove WARN_ON, convert to netdev block comments]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: use devm_platform_ioremap_resource_byname

Use the devm_platform_ioremap_resource_byname() helper instead of
calling platform_get_resource_byname() and devm_ioremap_resource()
separately.

Link: https://lore.kernel.org/r/20210603073441.2983497-1-yangyingliang@huawei.com
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: Add support for transceiver as phy

Add support for implementing transceiver node as phy. The max_bitrate
is obtained by getting a phy attribute.

Link: https://lore.kernel.org/r/20210724174001.553047-1-mkl@pengutronix.de
Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: use struct m_can_classdev as drvdata

The m_can driver's suspend and resume functions (m_can_class_suspend() and
m_can_class_resume()) make use of dev_get_drvdata() and assume that the drvdata
is a pointer to the struct net_device.

With upcoming conversion of the tcan4x5x driver to pm_runtime this assumption
is no longer valid. As the suspend and resume functions actually need a struct
m_can_classdev pointer, change the m_can_platform and the m_can_pci driver to
hold a pointer to struct m_can_classdev instead, as the tcan4x5x driver already
does.

Link: https://lore.kernel.org/r/20201212175518.139651-8-mkl@pengutronix.de
Reviewed-by: Sean Nyekjaer <sean@geanix.com>
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: let m_can_class_allocate_dev() allocate driver specific private data

This patch enhances m_can_class_allocate_dev() to allocate driver specific
private data. The driver's private data struct must contain struct
m_can_classdev as its first member followed by the remaining private data.

Link: https://lore.kernel.org/r/20201212175518.139651-7-mkl@pengutronix.de
Reviewed-by: Sean Nyekjaer <sean@geanix.com>
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: move runtime PM enable/disable to m_can_platform

This is a preparatory patch for upcoming PCI based M_CAN devices. The current
PM implementation would cause PCI based drivers to enable PM twice, once when
the PCI device is added and a second time in m_can_class_register(). This will
cause 'Unbalanced pm_runtime_enable!' to be logged, and is a situation that
should be avoided.

Therefore, in anticipation of PCI devices, move PM enabling out from M_CAN
class registration to its only user, the m_can_platform driver.

Signed-off-by: Patrik Flykt <patrik.flykt@linux.intel.com>
Link: https://lore.kernel.org/r/20201023115800.46538-2-patrik.flykt@linux.intel.com
[mkl: m_can_plat_probe(): fix error handling
m_can_class_register(): simplify error handling]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: m_can_plat_remove(): remove unneeded platform_set_drvdata()

There's no need to unset the drvdata on remove, so remove the unneeded call to
platform_set_drvdata() in m_can_plat_remove().

Link: https://lore.kernel.org/r/20201130133713.269256-6-mkl@pengutronix.de
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: Fix freeing of can device from peripherials

Fix leaking netdev device from peripherial devices. The call to allocate the
netdev device is made from and managed by the peripherial.

Fixes: f524f829b75a ("can: m_can: Create a m_can platform framework")
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Link: http://lore.kernel.org/r/20200227183829.21854-2-dmurphy@ti.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can_platform: don't call m_can_class_suspend in runtime suspend

0704c5743694 can: m_can_platform: remove unnecessary m_can_class_resume() call

removed the m_can_class_resume() call in the runtime resume path to get
rid of a infinite recursion, so the runtime resume now only handles the device
clocks.

Unfortunately it did not remove the complementary m_can_class_suspend() call in
the runtime suspend function, so those paths are now unbalanced, which causes
the pinctrl state to get stuck on the "sleep" state, which breaks all CAN
functionality on SoCs where this state is defined. Remove the
m_can_class_suspend() call to fix this.

Fixes: 0704c5743694 can: m_can_platform: remove unnecessary m_can_class_resume() call
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Link: https://lore.kernel.org/r/20200811081545.19921-1-l.stach@pengutronix.de
Acked-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can_platform: remove unnecessary m_can_class_resume() call

The function m_can_runtime_resume() is getting recursively called from
m_can_class_resume(). This results in a lock up.

We need not call m_can_class_resume() during m_can_runtime_resume().

Fixes: f524f829b75a ("can: m_can: Create a m_can platform framework")
Signed-off-by: Pankaj Sharma <pankj.sharma@samsung.com>
Signed-off-by: Sriram Dash <sriram.dash@samsung.com>
Acked-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can_platform: set net_device structure as driver data

The current code is failing during clock prepare enable because of not
getting proper clock from platform device.

[ 0.852089] Call trace:
[ 0.854516] 0xffff0000fa22a668
[ 0.857638] clk_prepare+0x20/0x34
[ 0.861019] m_can_runtime_resume+0x2c/0xe4
[ 0.865180] pm_generic_runtime_resume+0x28/0x38
[ 0.869770] __rpm_callback+0x16c/0x1bc
[ 0.873583] rpm_callback+0x24/0x78
[ 0.877050] rpm_resume+0x428/0x560
[ 0.880517] __pm_runtime_resume+0x7c/0xa8
[ 0.884593] m_can_clk_start.isra.9.part.10+0x1c/0xa8
[ 0.889618] m_can_class_register+0x138/0x370
[ 0.893950] m_can_plat_probe+0x120/0x170
[ 0.897939] platform_drv_probe+0x4c/0xa0
[ 0.901924] really_probe+0xd8/0x31c
[ 0.905477] driver_probe_device+0x58/0xe8
[ 0.909551] device_driver_attach+0x68/0x70
[ 0.913711] __driver_attach+0x9c/0xf8
[ 0.917437] bus_for_each_dev+0x50/0xa0
[ 0.921251] driver_attach+0x20/0x28
[ 0.924804] bus_add_driver+0x148/0x1fc
[ 0.928617] driver_register+0x6c/0x124
[ 0.932431] __platform_driver_register+0x48/0x50
[ 0.937113] m_can_plat_driver_init+0x18/0x20
[ 0.941446] do_one_initcall+0x4c/0x19c
[ 0.945259] kernel_init_freeable+0x1d0/0x280
[ 0.949591] kernel_init+0x10/0x100
[ 0.953057] ret_from_fork+0x10/0x18
[ 0.956614] Code: 00000000 00000000 00000000 00000000 (fa22a668)
[ 0.962681] ---[ end trace 881f71bd609de763 ]---
[ 0.967301] Kernel panic - not syncing: Attempted to kill init!

A device driver for CAN controller hardware registers itself with the
Linux network layer as a network device. So, the driver data for m_can
should ideally be of type net_device.

Fixes: f524f829b75a ("can: m_can: Create a m_can platform framework")
Signed-off-by: Pankaj Sharma <pankj.sharma@samsung.com>
Signed-off-by: Sriram Dash <sriram.dash@samsung.com>
Acked-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can_platform: m_can_plat_probe(): add missing error handling if mcan_class is NULL

This patch adds the missing error handling in m_can_plat_probe() if
mcan_class is NULL.

Fixes: f524f829b75a ("can: m_can: Create a m_can platform framework")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can_platform: remove not needed casts to struct m_can_plat_priv *

The struct m_can_classdev::device_data is a void pointer, so there's no
need to cast it to struct m_can_plat_priv *, when assigning the struct
m_can_plat_priv pointer.

This patch removes the not needed casts from the m_can_platform driver.

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

can: m_can: Rename m_can_priv to m_can_classdev

Rename the common m_can_priv class structure to m_can_classdev as this
is more descriptive.

Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can: m_can: Create a m_can platform framework

Create a m_can platform framework that peripheral
devices can register to and use common code and register sets.
The peripheral devices may provide read/write and configuration
support of the IP.

Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>