In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.
Because the match() callback is in all busses, all busses are modified
to handle this properly. This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.
For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.
Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the phy reset sequence is as shown below for a
devicetree described mdio phy on boot:
1. Assert the phy_device's reset as part of registering
2. Deassert the phy_device's reset as part of registering
3. Deassert the phy_device's reset as part of phy_probe
4. Deassert the phy_device's reset as part of phy_hw_init
The extra two deasserts include waiting the deassert delay afterwards,
which is adding unnecessary delay.
This applies to both possible types of resets (reset controller
reference and a reset gpio) that can be used.
Here's some snipped tracing output using the following command line
params "trace_event=gpio:* trace_options=stacktrace" illustrating
the reset handling and where its coming from:
/* Assert */
systemd-udevd-283 [002] ..... 6.780434: gpio_value: 544 set 0
systemd-udevd-283 [002] ..... 6.783849: <stack trace>
=> gpiod_set_raw_value_commit
=> gpiod_set_value_nocheck
=> gpiod_set_value_cansleep
=> mdio_device_reset
=> mdiobus_register_device
=> phy_device_register
=> fwnode_mdiobus_phy_device_register
=> fwnode_mdiobus_register_phy
=> __of_mdiobus_register
=> stmmac_mdio_register
=> stmmac_dvr_probe
=> stmmac_pltfr_probe
=> devm_stmmac_pltfr_probe
=> qcom_ethqos_probe
=> platform_probe
/* Deassert */
systemd-udevd-283 [002] ..... 6.802480: gpio_value: 544 set 1
systemd-udevd-283 [002] ..... 6.805886: <stack trace>
=> gpiod_set_raw_value_commit
=> gpiod_set_value_nocheck
=> gpiod_set_value_cansleep
=> mdio_device_reset
=> phy_device_register
=> fwnode_mdiobus_phy_device_register
=> fwnode_mdiobus_register_phy
=> __of_mdiobus_register
=> stmmac_mdio_register
=> stmmac_dvr_probe
=> stmmac_pltfr_probe
=> devm_stmmac_pltfr_probe
=> qcom_ethqos_probe
=> platform_probe
/* Deassert */
systemd-udevd-283 [002] ..... 6.882601: gpio_value: 544 set 1
systemd-udevd-283 [002] ..... 6.886014: <stack trace>
=> gpiod_set_raw_value_commit
=> gpiod_set_value_nocheck
=> gpiod_set_value_cansleep
=> mdio_device_reset
=> phy_probe
=> really_probe
=> __driver_probe_device
=> driver_probe_device
=> __device_attach_driver
=> bus_for_each_drv
=> __device_attach
=> device_initial_probe
=> bus_probe_device
=> device_add
=> phy_device_register
=> fwnode_mdiobus_phy_device_register
=> fwnode_mdiobus_register_phy
=> __of_mdiobus_register
=> stmmac_mdio_register
=> stmmac_dvr_probe
=> stmmac_pltfr_probe
=> devm_stmmac_pltfr_probe
=> qcom_ethqos_probe
=> platform_probe
/* Deassert */
NetworkManager-477 [000] ..... 7.023144: gpio_value: 544 set 1
NetworkManager-477 [000] ..... 7.026596: <stack trace>
=> gpiod_set_raw_value_commit
=> gpiod_set_value_nocheck
=> gpiod_set_value_cansleep
=> mdio_device_reset
=> phy_init_hw
=> phy_attach_direct
=> phylink_fwnode_phy_connect
=> __stmmac_open
=> stmmac_open
There's a lot of paths where the device is getting its reset
asserted and deasserted. Let's track the state and only actually
do the assert/deassert when it changes.
Reported-by: Sagar Cheluvegowda <quic_scheluve@quicinc.com>
Signed-off-by: Andrew Halaney <ahalaney@redhat.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20231127-net-phy-reset-once-v2-1-448e8658779e@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There is warning report about of_node refcount leak
while probing mdio device:
OF: ERROR: memory leak, expected refcount 1 instead of 2,
of_node_get()/of_node_put() unbalanced - destroy cset entry:
attach overlay node /spi/soc@0/mdio@710700c0/ethernet@4
In of_mdiobus_register_device(), we increase fwnode refcount
by fwnode_handle_get() before associating the of_node with
mdio device, but it has never been decreased in normal path.
Since that, in mdio_device_release(), it needs to call
fwnode_handle_put() in addition instead of calling kfree()
directly.
After above, just calling mdio_device_free() in the error handle
path of of_mdiobus_register_device() is enough to keep the
refcount balanced.
Fixes: a9049e0c51 ("mdio: Add support for mdio drivers.")
Signed-off-by: Zeng Heng <zengheng4@huawei.com>
Reviewed-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://lore.kernel.org/r/20221203073441.3885317-1-zengheng4@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
MDIO-attached devices might have interrupts and other things that might
need quiesced when we kexec into a new kernel. Things are even more
creepy when those interrupt lines are shared, and in that case it is
absolutely mandatory to disable all interrupt sources.
Moreover, MDIO devices might be DSA switches, and DSA needs its own
shutdown method to unlink from the DSA master, which is a new
requirement that appeared after commit 2f1e8ea726 ("net: dsa: link
interfaces with the DSA master to get rid of lockdep warnings").
So introduce a ->shutdown method in the MDIO device driver structure.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's better to use __func__ than a fixed string to print a function's
name.
Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
MDIO device reset assert and deassert length was created by
usleep_range() but that does not ensure optimal handling of
all the different values from device tree properties.
By switching to the new flexible sleeping helper function,
fsleep(), the correct delay function is called depending on
delay length, e.g. udelay(), usleep_range() or msleep().
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Correct the kerneldoc for a few structure and function calls,
as reported by C=1 W=1.
Cc: Alexandru Ardelean <alexaundru.ardelean@analog.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similarily to PHY drivers - there's no reason to require probe() to be
implemented in order to call mdio_device_reset(). MDIO devices can have
resets defined without needing to do anything in probe().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Keeping the headers in alphabetical order is better for readability and
allows to easily see if given header is already included.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mdio_device_reset() makes use of the atomic-pretending API flavor for
handling the PHY reset GPIO line.
I found no hint that mdio_device_reset() is called from atomic context
and indeed it uses usleep_range() since long time, so I would assume that
it is OK to sleep there.
This patch switch to gpiod_set_value_cansleep() in mdio_device_reset().
This is relevant if e.g. the PHY reset line is tied to a I2C GPIO
controller.
This has been tested on a ZynqMP board running an upstream 4.19 kernel and
then hand-ported on current kernel tree.
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This renames the GPIO reset of mdio devices from 'reset' to
'reset_gpio' to better differentiate between GPIO and
reset-controller driven reset line.
Signed-off-by: David Bauer <mail@david-bauer.net>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit adds support for PHY reset pins handled by a reset controller.
Signed-off-by: David Bauer <mail@david-bauer.net>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Where the license text and the MODULE_LICENSE() value agree, convert
to using an SPDX header, removing the license text.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
As suggested by Rob Herring [1] rename the previously introduced
reset-{,post-}delay-us bindings to the clearer reset-{,de}assert-us
[1] https://patchwork.kernel.org/patch/10104905/
Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some PHYs need a minimum time after the reset gpio was asserted and/or
deasserted. To ensure we meet these timing requirements add two new
optional devicetree parameters for the phy: reset-delay-us and
reset-post-delay-us.
Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PHY devices sometimes do have their reset signal (maybe even power
supply?) tied to some GPIO and sometimes it also does happen that a boot
loader does not leave it deasserted. So far this issue has been attacked
from (as I believe) a wrong angle: by teaching the MAC driver to manipulate
the GPIO in question; that solution, when applied to the device trees, led
to adding the PHY reset GPIO properties to the MAC device node, with one
exception: Cadence MACB driver which could handle the "reset-gpios" prop
in a PHY device subnode. I believe that the correct approach is to teach
the 'phylib' to get the MDIO device reset GPIO from the device tree node
corresponding to this device -- which this patch is doing...
Note that I had to modify the AT803x PHY driver as it would stop working
otherwise -- it made use of the reset GPIO for its own purposes...
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Rob Herring <robh@kernel.org>
[geert: Propagate actual errors from fwnode_get_named_gpiod()]
[geert: Avoid destroying initial setup]
[geert: Consolidate GPIO descriptor acquiring code]
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Richard Leitner <richard.leitner@skidata.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow board support code to collect pre-declarations for MDIO devices by
registering them with mdiobus_register_board_info(). SPI and I2C buses
have a similar feature, we were missing this for MDIO devices, but this
is particularly useful for e.g: MDIO-connected switches which need to
provide their port layout (often board-specific) to a MDIO Ethernet
switch driver.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While it is useful to know which MDIO device is being registered, demote
the dev_info() to a dev_dbg().
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
While it is useful to know which MDIO driver is being registered, demote
the pr_info() to a pr_debug().
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make device_free and device_remove operations in the mdio device
structure, so the core code does not need to differentiate between
phy devices and generic mdio devices.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Not all devices on an MDIO bus are PHYs. Meaning not all MDIO drivers
are PHY drivers. Add support for generic MDIO drivers.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
