![Sergei Shtylyov](/assets/img/avatar_default.png)
I've finally noticed that mdiobus_scan() also returns either NULL or error value on failure. Return ERR_PTR(-ENODEV) instead of NULL since this is the error value already filtered out by the callers that want to ignore the MDIO address scan failure... Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: David S. Miller <davem@davemloft.net>
642 lines
15 KiB
C
642 lines
15 KiB
C
/* MDIO Bus interface
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*
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* Author: Andy Fleming
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*
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* Copyright (c) 2004 Freescale Semiconductor, Inc.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; either version 2 of the License, or (at your
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* option) any later version.
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*
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/errno.h>
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#include <linux/unistd.h>
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#include <linux/slab.h>
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#include <linux/interrupt.h>
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#include <linux/init.h>
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#include <linux/delay.h>
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#include <linux/device.h>
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#include <linux/of_device.h>
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#include <linux/of_mdio.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/skbuff.h>
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#include <linux/spinlock.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/mii.h>
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#include <linux/ethtool.h>
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#include <linux/phy.h>
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#include <linux/io.h>
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#include <linux/uaccess.h>
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#include <asm/irq.h>
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int mdiobus_register_device(struct mdio_device *mdiodev)
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{
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if (mdiodev->bus->mdio_map[mdiodev->addr])
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return -EBUSY;
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mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
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return 0;
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}
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EXPORT_SYMBOL(mdiobus_register_device);
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int mdiobus_unregister_device(struct mdio_device *mdiodev)
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{
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if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
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return -EINVAL;
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mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
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return 0;
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}
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EXPORT_SYMBOL(mdiobus_unregister_device);
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struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)
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{
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struct mdio_device *mdiodev = bus->mdio_map[addr];
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if (!mdiodev)
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return NULL;
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if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
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return NULL;
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return container_of(mdiodev, struct phy_device, mdio);
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}
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EXPORT_SYMBOL(mdiobus_get_phy);
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bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
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{
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return bus->mdio_map[addr];
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}
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EXPORT_SYMBOL(mdiobus_is_registered_device);
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/**
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* mdiobus_alloc_size - allocate a mii_bus structure
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* @size: extra amount of memory to allocate for private storage.
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* If non-zero, then bus->priv is points to that memory.
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*
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* Description: called by a bus driver to allocate an mii_bus
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* structure to fill in.
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*/
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struct mii_bus *mdiobus_alloc_size(size_t size)
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{
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struct mii_bus *bus;
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size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
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size_t alloc_size;
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int i;
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/* If we alloc extra space, it should be aligned */
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if (size)
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alloc_size = aligned_size + size;
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else
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alloc_size = sizeof(*bus);
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bus = kzalloc(alloc_size, GFP_KERNEL);
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if (!bus)
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return NULL;
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bus->state = MDIOBUS_ALLOCATED;
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if (size)
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bus->priv = (void *)bus + aligned_size;
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/* Initialise the interrupts to polling */
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for (i = 0; i < PHY_MAX_ADDR; i++)
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bus->irq[i] = PHY_POLL;
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return bus;
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}
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EXPORT_SYMBOL(mdiobus_alloc_size);
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static void _devm_mdiobus_free(struct device *dev, void *res)
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{
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mdiobus_free(*(struct mii_bus **)res);
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}
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static int devm_mdiobus_match(struct device *dev, void *res, void *data)
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{
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struct mii_bus **r = res;
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if (WARN_ON(!r || !*r))
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return 0;
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return *r == data;
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}
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/**
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* devm_mdiobus_alloc_size - Resource-managed mdiobus_alloc_size()
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* @dev: Device to allocate mii_bus for
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* @sizeof_priv: Space to allocate for private structure.
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*
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* Managed mdiobus_alloc_size. mii_bus allocated with this function is
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* automatically freed on driver detach.
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*
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* If an mii_bus allocated with this function needs to be freed separately,
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* devm_mdiobus_free() must be used.
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*
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* RETURNS:
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* Pointer to allocated mii_bus on success, NULL on failure.
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*/
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struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv)
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{
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struct mii_bus **ptr, *bus;
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ptr = devres_alloc(_devm_mdiobus_free, sizeof(*ptr), GFP_KERNEL);
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if (!ptr)
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return NULL;
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/* use raw alloc_dr for kmalloc caller tracing */
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bus = mdiobus_alloc_size(sizeof_priv);
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if (bus) {
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*ptr = bus;
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devres_add(dev, ptr);
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} else {
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devres_free(ptr);
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}
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return bus;
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}
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EXPORT_SYMBOL_GPL(devm_mdiobus_alloc_size);
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/**
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* devm_mdiobus_free - Resource-managed mdiobus_free()
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* @dev: Device this mii_bus belongs to
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* @bus: the mii_bus associated with the device
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*
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* Free mii_bus allocated with devm_mdiobus_alloc_size().
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*/
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void devm_mdiobus_free(struct device *dev, struct mii_bus *bus)
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{
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int rc;
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rc = devres_release(dev, _devm_mdiobus_free,
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devm_mdiobus_match, bus);
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WARN_ON(rc);
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}
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EXPORT_SYMBOL_GPL(devm_mdiobus_free);
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/**
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* mdiobus_release - mii_bus device release callback
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* @d: the target struct device that contains the mii_bus
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*
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* Description: called when the last reference to an mii_bus is
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* dropped, to free the underlying memory.
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*/
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static void mdiobus_release(struct device *d)
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{
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struct mii_bus *bus = to_mii_bus(d);
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BUG_ON(bus->state != MDIOBUS_RELEASED &&
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/* for compatibility with error handling in drivers */
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bus->state != MDIOBUS_ALLOCATED);
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kfree(bus);
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}
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static struct class mdio_bus_class = {
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.name = "mdio_bus",
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.dev_release = mdiobus_release,
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};
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#if IS_ENABLED(CONFIG_OF_MDIO)
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/* Helper function for of_mdio_find_bus */
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static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np)
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{
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return dev->of_node == mdio_bus_np;
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}
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/**
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* of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
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* @mdio_bus_np: Pointer to the mii_bus.
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*
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* Returns a reference to the mii_bus, or NULL if none found. The
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* embedded struct device will have its reference count incremented,
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* and this must be put once the bus is finished with.
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*
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* Because the association of a device_node and mii_bus is made via
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* of_mdiobus_register(), the mii_bus cannot be found before it is
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* registered with of_mdiobus_register().
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*
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*/
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struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
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{
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struct device *d;
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if (!mdio_bus_np)
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return NULL;
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d = class_find_device(&mdio_bus_class, NULL, mdio_bus_np,
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of_mdio_bus_match);
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return d ? to_mii_bus(d) : NULL;
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}
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EXPORT_SYMBOL(of_mdio_find_bus);
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/* Walk the list of subnodes of a mdio bus and look for a node that
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* matches the mdio device's address with its 'reg' property. If
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* found, set the of_node pointer for the mdio device. This allows
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* auto-probed phy devices to be supplied with information passed in
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* via DT.
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*/
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static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
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struct mdio_device *mdiodev)
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{
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struct device *dev = &mdiodev->dev;
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struct device_node *child;
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if (dev->of_node || !bus->dev.of_node)
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return;
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for_each_available_child_of_node(bus->dev.of_node, child) {
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int addr;
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int ret;
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ret = of_property_read_u32(child, "reg", &addr);
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if (ret < 0) {
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dev_err(dev, "%s has invalid MDIO address\n",
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child->full_name);
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continue;
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}
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/* A MDIO device must have a reg property in the range [0-31] */
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if (addr >= PHY_MAX_ADDR) {
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dev_err(dev, "%s MDIO address %i is too large\n",
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child->full_name, addr);
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continue;
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}
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if (addr == mdiodev->addr) {
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dev->of_node = child;
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return;
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}
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}
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}
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#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
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static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
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struct mdio_device *mdiodev)
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{
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}
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#endif
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/**
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* __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
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* @bus: target mii_bus
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* @owner: module containing bus accessor functions
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*
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* Description: Called by a bus driver to bring up all the PHYs
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* on a given bus, and attach them to the bus. Drivers should use
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* mdiobus_register() rather than __mdiobus_register() unless they
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* need to pass a specific owner module. MDIO devices which are not
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* PHYs will not be brought up by this function. They are expected to
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* to be explicitly listed in DT and instantiated by of_mdiobus_register().
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*
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* Returns 0 on success or < 0 on error.
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*/
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int __mdiobus_register(struct mii_bus *bus, struct module *owner)
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{
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struct mdio_device *mdiodev;
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int i, err;
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if (NULL == bus || NULL == bus->name ||
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NULL == bus->read || NULL == bus->write)
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return -EINVAL;
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BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
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bus->state != MDIOBUS_UNREGISTERED);
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bus->owner = owner;
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bus->dev.parent = bus->parent;
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bus->dev.class = &mdio_bus_class;
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bus->dev.groups = NULL;
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dev_set_name(&bus->dev, "%s", bus->id);
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err = device_register(&bus->dev);
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if (err) {
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pr_err("mii_bus %s failed to register\n", bus->id);
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put_device(&bus->dev);
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return -EINVAL;
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}
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mutex_init(&bus->mdio_lock);
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if (bus->reset)
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bus->reset(bus);
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for (i = 0; i < PHY_MAX_ADDR; i++) {
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if ((bus->phy_mask & (1 << i)) == 0) {
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struct phy_device *phydev;
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phydev = mdiobus_scan(bus, i);
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if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {
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err = PTR_ERR(phydev);
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goto error;
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}
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}
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}
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bus->state = MDIOBUS_REGISTERED;
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pr_info("%s: probed\n", bus->name);
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return 0;
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error:
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while (--i >= 0) {
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mdiodev = bus->mdio_map[i];
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if (!mdiodev)
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continue;
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mdiodev->device_remove(mdiodev);
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mdiodev->device_free(mdiodev);
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}
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device_del(&bus->dev);
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return err;
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}
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EXPORT_SYMBOL(__mdiobus_register);
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void mdiobus_unregister(struct mii_bus *bus)
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{
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struct mdio_device *mdiodev;
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int i;
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BUG_ON(bus->state != MDIOBUS_REGISTERED);
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bus->state = MDIOBUS_UNREGISTERED;
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for (i = 0; i < PHY_MAX_ADDR; i++) {
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mdiodev = bus->mdio_map[i];
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if (!mdiodev)
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continue;
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mdiodev->device_remove(mdiodev);
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mdiodev->device_free(mdiodev);
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}
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device_del(&bus->dev);
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}
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EXPORT_SYMBOL(mdiobus_unregister);
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/**
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* mdiobus_free - free a struct mii_bus
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* @bus: mii_bus to free
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*
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* This function releases the reference to the underlying device
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* object in the mii_bus. If this is the last reference, the mii_bus
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* will be freed.
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*/
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void mdiobus_free(struct mii_bus *bus)
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{
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/* For compatibility with error handling in drivers. */
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if (bus->state == MDIOBUS_ALLOCATED) {
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kfree(bus);
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return;
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}
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BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
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bus->state = MDIOBUS_RELEASED;
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put_device(&bus->dev);
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}
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EXPORT_SYMBOL(mdiobus_free);
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/**
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* mdiobus_scan - scan a bus for MDIO devices.
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* @bus: mii_bus to scan
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* @addr: address on bus to scan
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*
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* This function scans the MDIO bus, looking for devices which can be
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* identified using a vendor/product ID in registers 2 and 3. Not all
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* MDIO devices have such registers, but PHY devices typically
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* do. Hence this function assumes anything found is a PHY, or can be
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* treated as a PHY. Other MDIO devices, such as switches, will
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* probably not be found during the scan.
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*/
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struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
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{
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struct phy_device *phydev;
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int err;
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phydev = get_phy_device(bus, addr, false);
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if (IS_ERR(phydev))
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return phydev;
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/*
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* For DT, see if the auto-probed phy has a correspoding child
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* in the bus node, and set the of_node pointer in this case.
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*/
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of_mdiobus_link_mdiodev(bus, &phydev->mdio);
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err = phy_device_register(phydev);
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if (err) {
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phy_device_free(phydev);
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return ERR_PTR(-ENODEV);
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}
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return phydev;
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}
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EXPORT_SYMBOL(mdiobus_scan);
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/**
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* mdiobus_read_nested - Nested version of the mdiobus_read function
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* @bus: the mii_bus struct
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* @addr: the phy address
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* @regnum: register number to read
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*
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* In case of nested MDIO bus access avoid lockdep false positives by
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* using mutex_lock_nested().
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*
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* NOTE: MUST NOT be called from interrupt context,
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* because the bus read/write functions may wait for an interrupt
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* to conclude the operation.
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*/
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int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
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{
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int retval;
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BUG_ON(in_interrupt());
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mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
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retval = bus->read(bus, addr, regnum);
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mutex_unlock(&bus->mdio_lock);
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return retval;
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}
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EXPORT_SYMBOL(mdiobus_read_nested);
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/**
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* mdiobus_read - Convenience function for reading a given MII mgmt register
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* @bus: the mii_bus struct
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* @addr: the phy address
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* @regnum: register number to read
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*
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* NOTE: MUST NOT be called from interrupt context,
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* because the bus read/write functions may wait for an interrupt
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* to conclude the operation.
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*/
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int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
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{
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int retval;
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BUG_ON(in_interrupt());
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mutex_lock(&bus->mdio_lock);
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retval = bus->read(bus, addr, regnum);
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mutex_unlock(&bus->mdio_lock);
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return retval;
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}
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EXPORT_SYMBOL(mdiobus_read);
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/**
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* mdiobus_write_nested - Nested version of the mdiobus_write function
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* @bus: the mii_bus struct
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* @addr: the phy address
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* @regnum: register number to write
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* @val: value to write to @regnum
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*
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* In case of nested MDIO bus access avoid lockdep false positives by
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* using mutex_lock_nested().
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*
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* NOTE: MUST NOT be called from interrupt context,
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* because the bus read/write functions may wait for an interrupt
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* to conclude the operation.
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*/
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int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
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{
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int err;
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BUG_ON(in_interrupt());
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mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
|
|
err = bus->write(bus, addr, regnum, val);
|
|
mutex_unlock(&bus->mdio_lock);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(mdiobus_write_nested);
|
|
|
|
/**
|
|
* mdiobus_write - Convenience function for writing a given MII mgmt register
|
|
* @bus: the mii_bus struct
|
|
* @addr: the phy address
|
|
* @regnum: register number to write
|
|
* @val: value to write to @regnum
|
|
*
|
|
* NOTE: MUST NOT be called from interrupt context,
|
|
* because the bus read/write functions may wait for an interrupt
|
|
* to conclude the operation.
|
|
*/
|
|
int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
|
|
{
|
|
int err;
|
|
|
|
BUG_ON(in_interrupt());
|
|
|
|
mutex_lock(&bus->mdio_lock);
|
|
err = bus->write(bus, addr, regnum, val);
|
|
mutex_unlock(&bus->mdio_lock);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(mdiobus_write);
|
|
|
|
/**
|
|
* mdio_bus_match - determine if given MDIO driver supports the given
|
|
* MDIO device
|
|
* @dev: target MDIO device
|
|
* @drv: given MDIO driver
|
|
*
|
|
* Description: Given a MDIO device, and a MDIO driver, return 1 if
|
|
* the driver supports the device. Otherwise, return 0. This may
|
|
* require calling the devices own match function, since different classes
|
|
* of MDIO devices have different match criteria.
|
|
*/
|
|
static int mdio_bus_match(struct device *dev, struct device_driver *drv)
|
|
{
|
|
struct mdio_device *mdio = to_mdio_device(dev);
|
|
|
|
if (of_driver_match_device(dev, drv))
|
|
return 1;
|
|
|
|
if (mdio->bus_match)
|
|
return mdio->bus_match(dev, drv);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
static int mdio_bus_suspend(struct device *dev)
|
|
{
|
|
struct mdio_device *mdio = to_mdio_device(dev);
|
|
|
|
if (mdio->pm_ops && mdio->pm_ops->suspend)
|
|
return mdio->pm_ops->suspend(dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mdio_bus_resume(struct device *dev)
|
|
{
|
|
struct mdio_device *mdio = to_mdio_device(dev);
|
|
|
|
if (mdio->pm_ops && mdio->pm_ops->resume)
|
|
return mdio->pm_ops->resume(dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mdio_bus_restore(struct device *dev)
|
|
{
|
|
struct mdio_device *mdio = to_mdio_device(dev);
|
|
|
|
if (mdio->pm_ops && mdio->pm_ops->restore)
|
|
return mdio->pm_ops->restore(dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct dev_pm_ops mdio_bus_pm_ops = {
|
|
.suspend = mdio_bus_suspend,
|
|
.resume = mdio_bus_resume,
|
|
.freeze = mdio_bus_suspend,
|
|
.thaw = mdio_bus_resume,
|
|
.restore = mdio_bus_restore,
|
|
};
|
|
|
|
#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
|
|
|
|
#else
|
|
|
|
#define MDIO_BUS_PM_OPS NULL
|
|
|
|
#endif /* CONFIG_PM */
|
|
|
|
struct bus_type mdio_bus_type = {
|
|
.name = "mdio_bus",
|
|
.match = mdio_bus_match,
|
|
.pm = MDIO_BUS_PM_OPS,
|
|
};
|
|
EXPORT_SYMBOL(mdio_bus_type);
|
|
|
|
int __init mdio_bus_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = class_register(&mdio_bus_class);
|
|
if (!ret) {
|
|
ret = bus_register(&mdio_bus_type);
|
|
if (ret)
|
|
class_unregister(&mdio_bus_class);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
void mdio_bus_exit(void)
|
|
{
|
|
class_unregister(&mdio_bus_class);
|
|
bus_unregister(&mdio_bus_type);
|
|
}
|