diff options
Diffstat (limited to 'drivers/net/mdio/of_mdio.c')
| -rw-r--r-- | drivers/net/mdio/of_mdio.c | 445 |
1 files changed, 445 insertions, 0 deletions
diff --git a/drivers/net/mdio/of_mdio.c b/drivers/net/mdio/of_mdio.c new file mode 100644 index 000000000..1e46e39f5 --- /dev/null +++ b/drivers/net/mdio/of_mdio.c @@ -0,0 +1,445 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * OF helpers for the MDIO (Ethernet PHY) API + * + * Copyright (c) 2009 Secret Lab Technologies, Ltd. + * + * This file provides helper functions for extracting PHY device information + * out of the OpenFirmware device tree and using it to populate an mii_bus. + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/fwnode_mdio.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/of_mdio.h> +#include <linux/of_net.h> +#include <linux/phy.h> +#include <linux/phy_fixed.h> + +#define DEFAULT_GPIO_RESET_DELAY 10 /* in microseconds */ + +MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); +MODULE_LICENSE("GPL"); + +/* Extract the clause 22 phy ID from the compatible string of the form + * ethernet-phy-idAAAA.BBBB */ +static int of_get_phy_id(struct device_node *device, u32 *phy_id) +{ + return fwnode_get_phy_id(of_fwnode_handle(device), phy_id); +} + +int of_mdiobus_phy_device_register(struct mii_bus *mdio, struct phy_device *phy, + struct device_node *child, u32 addr) +{ + return fwnode_mdiobus_phy_device_register(mdio, phy, + of_fwnode_handle(child), + addr); +} +EXPORT_SYMBOL(of_mdiobus_phy_device_register); + +static int of_mdiobus_register_phy(struct mii_bus *mdio, + struct device_node *child, u32 addr) +{ + return fwnode_mdiobus_register_phy(mdio, of_fwnode_handle(child), addr); +} + +static int of_mdiobus_register_device(struct mii_bus *mdio, + struct device_node *child, u32 addr) +{ + struct fwnode_handle *fwnode = of_fwnode_handle(child); + struct mdio_device *mdiodev; + int rc; + + mdiodev = mdio_device_create(mdio, addr); + if (IS_ERR(mdiodev)) + return PTR_ERR(mdiodev); + + /* Associate the OF node with the device structure so it + * can be looked up later. + */ + fwnode_handle_get(fwnode); + device_set_node(&mdiodev->dev, fwnode); + + /* All data is now stored in the mdiodev struct; register it. */ + rc = mdio_device_register(mdiodev); + if (rc) { + device_set_node(&mdiodev->dev, NULL); + fwnode_handle_put(fwnode); + mdio_device_free(mdiodev); + return rc; + } + + dev_dbg(&mdio->dev, "registered mdio device %pOFn at address %i\n", + child, addr); + return 0; +} + +/* The following is a list of PHY compatible strings which appear in + * some DTBs. The compatible string is never matched against a PHY + * driver, so is pointless. We only expect devices which are not PHYs + * to have a compatible string, so they can be matched to an MDIO + * driver. Encourage users to upgrade their DT blobs to remove these. + */ +static const struct of_device_id whitelist_phys[] = { + { .compatible = "brcm,40nm-ephy" }, + { .compatible = "broadcom,bcm5241" }, + { .compatible = "marvell,88E1111", }, + { .compatible = "marvell,88e1116", }, + { .compatible = "marvell,88e1118", }, + { .compatible = "marvell,88e1145", }, + { .compatible = "marvell,88e1149r", }, + { .compatible = "marvell,88e1310", }, + { .compatible = "marvell,88E1510", }, + { .compatible = "marvell,88E1514", }, + { .compatible = "moxa,moxart-rtl8201cp", }, + {} +}; + +/* + * Return true if the child node is for a phy. It must either: + * o Compatible string of "ethernet-phy-idX.X" + * o Compatible string of "ethernet-phy-ieee802.3-c45" + * o Compatible string of "ethernet-phy-ieee802.3-c22" + * o In the white list above (and issue a warning) + * o No compatibility string + * + * A device which is not a phy is expected to have a compatible string + * indicating what sort of device it is. + */ +bool of_mdiobus_child_is_phy(struct device_node *child) +{ + u32 phy_id; + + if (of_get_phy_id(child, &phy_id) != -EINVAL) + return true; + + if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45")) + return true; + + if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22")) + return true; + + if (of_match_node(whitelist_phys, child)) { + pr_warn(FW_WARN + "%pOF: Whitelisted compatible string. Please remove\n", + child); + return true; + } + + if (!of_find_property(child, "compatible", NULL)) + return true; + + return false; +} +EXPORT_SYMBOL(of_mdiobus_child_is_phy); + +/** + * __of_mdiobus_register - Register mii_bus and create PHYs from the device tree + * @mdio: pointer to mii_bus structure + * @np: pointer to device_node of MDIO bus. + * @owner: module owning the @mdio object. + * + * This function registers the mii_bus structure and registers a phy_device + * for each child node of @np. + */ +int __of_mdiobus_register(struct mii_bus *mdio, struct device_node *np, + struct module *owner) +{ + struct device_node *child; + bool scanphys = false; + int addr, rc; + + if (!np) + return __mdiobus_register(mdio, owner); + + /* Do not continue if the node is disabled */ + if (!of_device_is_available(np)) + return -ENODEV; + + /* Mask out all PHYs from auto probing. Instead the PHYs listed in + * the device tree are populated after the bus has been registered */ + mdio->phy_mask = ~0; + + device_set_node(&mdio->dev, of_fwnode_handle(np)); + + /* Get bus level PHY reset GPIO details */ + mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY; + of_property_read_u32(np, "reset-delay-us", &mdio->reset_delay_us); + mdio->reset_post_delay_us = 0; + of_property_read_u32(np, "reset-post-delay-us", &mdio->reset_post_delay_us); + + /* Register the MDIO bus */ + rc = __mdiobus_register(mdio, owner); + if (rc) + return rc; + + /* Loop over the child nodes and register a phy_device for each phy */ + for_each_available_child_of_node(np, child) { + addr = of_mdio_parse_addr(&mdio->dev, child); + if (addr < 0) { + scanphys = true; + continue; + } + + if (of_mdiobus_child_is_phy(child)) + rc = of_mdiobus_register_phy(mdio, child, addr); + else + rc = of_mdiobus_register_device(mdio, child, addr); + + if (rc == -ENODEV) + dev_err(&mdio->dev, + "MDIO device at address %d is missing.\n", + addr); + else if (rc) + goto unregister; + } + + if (!scanphys) + return 0; + + /* auto scan for PHYs with empty reg property */ + for_each_available_child_of_node(np, child) { + /* Skip PHYs with reg property set */ + if (of_find_property(child, "reg", NULL)) + continue; + + for (addr = 0; addr < PHY_MAX_ADDR; addr++) { + /* skip already registered PHYs */ + if (mdiobus_is_registered_device(mdio, addr)) + continue; + + /* be noisy to encourage people to set reg property */ + dev_info(&mdio->dev, "scan phy %pOFn at address %i\n", + child, addr); + + if (of_mdiobus_child_is_phy(child)) { + /* -ENODEV is the return code that PHYLIB has + * standardized on to indicate that bus + * scanning should continue. + */ + rc = of_mdiobus_register_phy(mdio, child, addr); + if (!rc) + break; + if (rc != -ENODEV) + goto unregister; + } + } + } + + return 0; + +unregister: + of_node_put(child); + mdiobus_unregister(mdio); + return rc; +} +EXPORT_SYMBOL(__of_mdiobus_register); + +/** + * of_mdio_find_device - Given a device tree node, find the mdio_device + * @np: pointer to the mdio_device's device tree node + * + * If successful, returns a pointer to the mdio_device with the embedded + * struct device refcount incremented by one, or NULL on failure. + * The caller should call put_device() on the mdio_device after its use + */ +struct mdio_device *of_mdio_find_device(struct device_node *np) +{ + return fwnode_mdio_find_device(of_fwnode_handle(np)); +} +EXPORT_SYMBOL(of_mdio_find_device); + +/** + * of_phy_find_device - Give a PHY node, find the phy_device + * @phy_np: Pointer to the phy's device tree node + * + * If successful, returns a pointer to the phy_device with the embedded + * struct device refcount incremented by one, or NULL on failure. + */ +struct phy_device *of_phy_find_device(struct device_node *phy_np) +{ + return fwnode_phy_find_device(of_fwnode_handle(phy_np)); +} +EXPORT_SYMBOL(of_phy_find_device); + +/** + * of_phy_connect - Connect to the phy described in the device tree + * @dev: pointer to net_device claiming the phy + * @phy_np: Pointer to device tree node for the PHY + * @hndlr: Link state callback for the network device + * @flags: flags to pass to the PHY + * @iface: PHY data interface type + * + * If successful, returns a pointer to the phy_device with the embedded + * struct device refcount incremented by one, or NULL on failure. The + * refcount must be dropped by calling phy_disconnect() or phy_detach(). + */ +struct phy_device *of_phy_connect(struct net_device *dev, + struct device_node *phy_np, + void (*hndlr)(struct net_device *), u32 flags, + phy_interface_t iface) +{ + struct phy_device *phy = of_phy_find_device(phy_np); + int ret; + + if (!phy) + return NULL; + + phy->dev_flags |= flags; + + ret = phy_connect_direct(dev, phy, hndlr, iface); + + /* refcount is held by phy_connect_direct() on success */ + put_device(&phy->mdio.dev); + + return ret ? NULL : phy; +} +EXPORT_SYMBOL(of_phy_connect); + +/** + * of_phy_get_and_connect + * - Get phy node and connect to the phy described in the device tree + * @dev: pointer to net_device claiming the phy + * @np: Pointer to device tree node for the net_device claiming the phy + * @hndlr: Link state callback for the network device + * + * If successful, returns a pointer to the phy_device with the embedded + * struct device refcount incremented by one, or NULL on failure. The + * refcount must be dropped by calling phy_disconnect() or phy_detach(). + */ +struct phy_device *of_phy_get_and_connect(struct net_device *dev, + struct device_node *np, + void (*hndlr)(struct net_device *)) +{ + phy_interface_t iface; + struct device_node *phy_np; + struct phy_device *phy; + int ret; + + ret = of_get_phy_mode(np, &iface); + if (ret) + return NULL; + if (of_phy_is_fixed_link(np)) { + ret = of_phy_register_fixed_link(np); + if (ret < 0) { + netdev_err(dev, "broken fixed-link specification\n"); + return NULL; + } + phy_np = of_node_get(np); + } else { + phy_np = of_parse_phandle(np, "phy-handle", 0); + if (!phy_np) + return NULL; + } + + phy = of_phy_connect(dev, phy_np, hndlr, 0, iface); + + of_node_put(phy_np); + + return phy; +} +EXPORT_SYMBOL(of_phy_get_and_connect); + +/* + * of_phy_is_fixed_link() and of_phy_register_fixed_link() must + * support two DT bindings: + * - the old DT binding, where 'fixed-link' was a property with 5 + * cells encoding various information about the fixed PHY + * - the new DT binding, where 'fixed-link' is a sub-node of the + * Ethernet device. + */ +bool of_phy_is_fixed_link(struct device_node *np) +{ + struct device_node *dn; + int len, err; + const char *managed; + + /* New binding */ + dn = of_get_child_by_name(np, "fixed-link"); + if (dn) { + of_node_put(dn); + return true; + } + + err = of_property_read_string(np, "managed", &managed); + if (err == 0 && strcmp(managed, "auto") != 0) + return true; + + /* Old binding */ + if (of_get_property(np, "fixed-link", &len) && + len == (5 * sizeof(__be32))) + return true; + + return false; +} +EXPORT_SYMBOL(of_phy_is_fixed_link); + +int of_phy_register_fixed_link(struct device_node *np) +{ + struct fixed_phy_status status = {}; + struct device_node *fixed_link_node; + u32 fixed_link_prop[5]; + const char *managed; + + if (of_property_read_string(np, "managed", &managed) == 0 && + strcmp(managed, "in-band-status") == 0) { + /* status is zeroed, namely its .link member */ + goto register_phy; + } + + /* New binding */ + fixed_link_node = of_get_child_by_name(np, "fixed-link"); + if (fixed_link_node) { + status.link = 1; + status.duplex = of_property_read_bool(fixed_link_node, + "full-duplex"); + if (of_property_read_u32(fixed_link_node, "speed", + &status.speed)) { + of_node_put(fixed_link_node); + return -EINVAL; + } + status.pause = of_property_read_bool(fixed_link_node, "pause"); + status.asym_pause = of_property_read_bool(fixed_link_node, + "asym-pause"); + of_node_put(fixed_link_node); + + goto register_phy; + } + + /* Old binding */ + if (of_property_read_u32_array(np, "fixed-link", fixed_link_prop, + ARRAY_SIZE(fixed_link_prop)) == 0) { + status.link = 1; + status.duplex = fixed_link_prop[1]; + status.speed = fixed_link_prop[2]; + status.pause = fixed_link_prop[3]; + status.asym_pause = fixed_link_prop[4]; + goto register_phy; + } + + return -ENODEV; + +register_phy: + return PTR_ERR_OR_ZERO(fixed_phy_register(PHY_POLL, &status, np)); +} +EXPORT_SYMBOL(of_phy_register_fixed_link); + +void of_phy_deregister_fixed_link(struct device_node *np) +{ + struct phy_device *phydev; + + phydev = of_phy_find_device(np); + if (!phydev) + return; + + fixed_phy_unregister(phydev); + + put_device(&phydev->mdio.dev); /* of_phy_find_device() */ + phy_device_free(phydev); /* fixed_phy_register() */ +} +EXPORT_SYMBOL(of_phy_deregister_fixed_link); |