Files
linux/drivers/net/phy/mdio_device.c
Vladimir Oltean a7cc3021e6 net: mdio: introduce a shutdown method to mdio device drivers
[ Upstream commit cf9579976f ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-16 12:00:02 +09:00

183 lines
4.3 KiB
C

/* Framework for MDIO devices, other than PHYs.
*
* Copyright (c) 2016 Andrew Lunn <andrew@lunn.ch>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mdio.h>
#include <linux/mii.h>
#include <linux/module.h>
#include <linux/phy.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/unistd.h>
void mdio_device_free(struct mdio_device *mdiodev)
{
put_device(&mdiodev->dev);
}
EXPORT_SYMBOL(mdio_device_free);
static void mdio_device_release(struct device *dev)
{
kfree(to_mdio_device(dev));
}
struct mdio_device *mdio_device_create(struct mii_bus *bus, int addr)
{
struct mdio_device *mdiodev;
/* We allocate the device, and initialize the default values */
mdiodev = kzalloc(sizeof(*mdiodev), GFP_KERNEL);
if (!mdiodev)
return ERR_PTR(-ENOMEM);
mdiodev->dev.release = mdio_device_release;
mdiodev->dev.parent = &bus->dev;
mdiodev->dev.bus = &mdio_bus_type;
mdiodev->device_free = mdio_device_free;
mdiodev->device_remove = mdio_device_remove;
mdiodev->bus = bus;
mdiodev->addr = addr;
dev_set_name(&mdiodev->dev, PHY_ID_FMT, bus->id, addr);
device_initialize(&mdiodev->dev);
return mdiodev;
}
EXPORT_SYMBOL(mdio_device_create);
/**
* mdio_device_register - Register the mdio device on the MDIO bus
* @mdiodev: mdio_device structure to be added to the MDIO bus
*/
int mdio_device_register(struct mdio_device *mdiodev)
{
int err;
dev_info(&mdiodev->dev, "mdio_device_register\n");
err = mdiobus_register_device(mdiodev);
if (err)
return err;
err = device_add(&mdiodev->dev);
if (err) {
pr_err("MDIO %d failed to add\n", mdiodev->addr);
goto out;
}
return 0;
out:
mdiobus_unregister_device(mdiodev);
return err;
}
EXPORT_SYMBOL(mdio_device_register);
/**
* mdio_device_remove - Remove a previously registered mdio device from the
* MDIO bus
* @mdiodev: mdio_device structure to remove
*
* This doesn't free the mdio_device itself, it merely reverses the effects
* of mdio_device_register(). Use mdio_device_free() to free the device
* after calling this function.
*/
void mdio_device_remove(struct mdio_device *mdiodev)
{
device_del(&mdiodev->dev);
mdiobus_unregister_device(mdiodev);
}
EXPORT_SYMBOL(mdio_device_remove);
/**
* mdio_probe - probe an MDIO device
* @dev: device to probe
*
* Description: Take care of setting up the mdio_device structure
* and calling the driver to probe the device.
*/
static int mdio_probe(struct device *dev)
{
struct mdio_device *mdiodev = to_mdio_device(dev);
struct device_driver *drv = mdiodev->dev.driver;
struct mdio_driver *mdiodrv = to_mdio_driver(drv);
int err = 0;
if (mdiodrv->probe)
err = mdiodrv->probe(mdiodev);
return err;
}
static int mdio_remove(struct device *dev)
{
struct mdio_device *mdiodev = to_mdio_device(dev);
struct device_driver *drv = mdiodev->dev.driver;
struct mdio_driver *mdiodrv = to_mdio_driver(drv);
if (mdiodrv->remove)
mdiodrv->remove(mdiodev);
return 0;
}
static void mdio_shutdown(struct device *dev)
{
struct mdio_device *mdiodev = to_mdio_device(dev);
struct device_driver *drv = mdiodev->dev.driver;
struct mdio_driver *mdiodrv = to_mdio_driver(drv);
if (mdiodrv->shutdown)
mdiodrv->shutdown(mdiodev);
}
/**
* mdio_driver_register - register an mdio_driver with the MDIO layer
* @new_driver: new mdio_driver to register
*/
int mdio_driver_register(struct mdio_driver *drv)
{
struct mdio_driver_common *mdiodrv = &drv->mdiodrv;
int retval;
pr_info("mdio_driver_register: %s\n", mdiodrv->driver.name);
mdiodrv->driver.bus = &mdio_bus_type;
mdiodrv->driver.probe = mdio_probe;
mdiodrv->driver.remove = mdio_remove;
mdiodrv->driver.shutdown = mdio_shutdown;
retval = driver_register(&mdiodrv->driver);
if (retval) {
pr_err("%s: Error %d in registering driver\n",
mdiodrv->driver.name, retval);
return retval;
}
return 0;
}
EXPORT_SYMBOL(mdio_driver_register);
void mdio_driver_unregister(struct mdio_driver *drv)
{
struct mdio_driver_common *mdiodrv = &drv->mdiodrv;
driver_unregister(&mdiodrv->driver);
}
EXPORT_SYMBOL(mdio_driver_unregister);