| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Fixed MDIO bus (MDIO bus emulation with fixed PHYs) |
| * |
| * Author: Vitaly Bordug <vbordug@ru.mvista.com> |
| * Anton Vorontsov <avorontsov@ru.mvista.com> |
| * |
| * Copyright (c) 2006-2007 MontaVista Software, Inc. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/list.h> |
| #include <linux/mii.h> |
| #include <linux/phy.h> |
| #include <linux/phy_fixed.h> |
| #include <linux/err.h> |
| #include <linux/slab.h> |
| #include <linux/of.h> |
| #include <linux/gpio/consumer.h> |
| #include <linux/seqlock.h> |
| #include <linux/idr.h> |
| #include <linux/netdevice.h> |
| #include <linux/linkmode.h> |
| |
| #include "swphy.h" |
| |
| struct fixed_mdio_bus { |
| struct mii_bus *mii_bus; |
| struct list_head phys; |
| }; |
| |
| struct fixed_phy { |
| int addr; |
| struct phy_device *phydev; |
| seqcount_t seqcount; |
| struct fixed_phy_status status; |
| bool no_carrier; |
| int (*link_update)(struct net_device *, struct fixed_phy_status *); |
| struct list_head node; |
| struct gpio_desc *link_gpiod; |
| }; |
| |
| static struct platform_device *pdev; |
| static struct fixed_mdio_bus platform_fmb = { |
| .phys = LIST_HEAD_INIT(platform_fmb.phys), |
| }; |
| |
| int fixed_phy_change_carrier(struct net_device *dev, bool new_carrier) |
| { |
| struct fixed_mdio_bus *fmb = &platform_fmb; |
| struct phy_device *phydev = dev->phydev; |
| struct fixed_phy *fp; |
| |
| if (!phydev || !phydev->mdio.bus) |
| return -EINVAL; |
| |
| list_for_each_entry(fp, &fmb->phys, node) { |
| if (fp->addr == phydev->mdio.addr) { |
| fp->no_carrier = !new_carrier; |
| return 0; |
| } |
| } |
| return -EINVAL; |
| } |
| EXPORT_SYMBOL_GPL(fixed_phy_change_carrier); |
| |
| static void fixed_phy_update(struct fixed_phy *fp) |
| { |
| if (!fp->no_carrier && fp->link_gpiod) |
| fp->status.link = !!gpiod_get_value_cansleep(fp->link_gpiod); |
| } |
| |
| static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num) |
| { |
| struct fixed_mdio_bus *fmb = bus->priv; |
| struct fixed_phy *fp; |
| |
| list_for_each_entry(fp, &fmb->phys, node) { |
| if (fp->addr == phy_addr) { |
| struct fixed_phy_status state; |
| int s; |
| |
| do { |
| s = read_seqcount_begin(&fp->seqcount); |
| fp->status.link = !fp->no_carrier; |
| /* Issue callback if user registered it. */ |
| if (fp->link_update) |
| fp->link_update(fp->phydev->attached_dev, |
| &fp->status); |
| /* Check the GPIO for change in status */ |
| fixed_phy_update(fp); |
| state = fp->status; |
| } while (read_seqcount_retry(&fp->seqcount, s)); |
| |
| return swphy_read_reg(reg_num, &state); |
| } |
| } |
| |
| return 0xFFFF; |
| } |
| |
| static int fixed_mdio_write(struct mii_bus *bus, int phy_addr, int reg_num, |
| u16 val) |
| { |
| return 0; |
| } |
| |
| /* |
| * If something weird is required to be done with link/speed, |
| * network driver is able to assign a function to implement this. |
| * May be useful for PHY's that need to be software-driven. |
| */ |
| int fixed_phy_set_link_update(struct phy_device *phydev, |
| int (*link_update)(struct net_device *, |
| struct fixed_phy_status *)) |
| { |
| struct fixed_mdio_bus *fmb = &platform_fmb; |
| struct fixed_phy *fp; |
| |
| if (!phydev || !phydev->mdio.bus) |
| return -EINVAL; |
| |
| list_for_each_entry(fp, &fmb->phys, node) { |
| if (fp->addr == phydev->mdio.addr) { |
| fp->link_update = link_update; |
| fp->phydev = phydev; |
| return 0; |
| } |
| } |
| |
| return -ENOENT; |
| } |
| EXPORT_SYMBOL_GPL(fixed_phy_set_link_update); |
| |
| static int fixed_phy_add_gpiod(unsigned int irq, int phy_addr, |
| struct fixed_phy_status *status, |
| struct gpio_desc *gpiod) |
| { |
| int ret; |
| struct fixed_mdio_bus *fmb = &platform_fmb; |
| struct fixed_phy *fp; |
| |
| ret = swphy_validate_state(status); |
| if (ret < 0) |
| return ret; |
| |
| fp = kzalloc(sizeof(*fp), GFP_KERNEL); |
| if (!fp) |
| return -ENOMEM; |
| |
| seqcount_init(&fp->seqcount); |
| |
| if (irq != PHY_POLL) |
| fmb->mii_bus->irq[phy_addr] = irq; |
| |
| fp->addr = phy_addr; |
| fp->status = *status; |
| fp->link_gpiod = gpiod; |
| |
| fixed_phy_update(fp); |
| |
| list_add_tail(&fp->node, &fmb->phys); |
| |
| return 0; |
| } |
| |
| int fixed_phy_add(unsigned int irq, int phy_addr, |
| struct fixed_phy_status *status) { |
| |
| return fixed_phy_add_gpiod(irq, phy_addr, status, NULL); |
| } |
| EXPORT_SYMBOL_GPL(fixed_phy_add); |
| |
| static DEFINE_IDA(phy_fixed_ida); |
| |
| static void fixed_phy_del(int phy_addr) |
| { |
| struct fixed_mdio_bus *fmb = &platform_fmb; |
| struct fixed_phy *fp, *tmp; |
| |
| list_for_each_entry_safe(fp, tmp, &fmb->phys, node) { |
| if (fp->addr == phy_addr) { |
| list_del(&fp->node); |
| if (fp->link_gpiod) |
| gpiod_put(fp->link_gpiod); |
| kfree(fp); |
| ida_simple_remove(&phy_fixed_ida, phy_addr); |
| return; |
| } |
| } |
| } |
| |
| #ifdef CONFIG_OF_GPIO |
| static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np) |
| { |
| struct device_node *fixed_link_node; |
| struct gpio_desc *gpiod; |
| |
| if (!np) |
| return NULL; |
| |
| fixed_link_node = of_get_child_by_name(np, "fixed-link"); |
| if (!fixed_link_node) |
| return NULL; |
| |
| /* |
| * As the fixed link is just a device tree node without any |
| * Linux device associated with it, we simply have obtain |
| * the GPIO descriptor from the device tree like this. |
| */ |
| gpiod = gpiod_get_from_of_node(fixed_link_node, "link-gpios", 0, |
| GPIOD_IN, "mdio"); |
| if (IS_ERR(gpiod) && PTR_ERR(gpiod) != -EPROBE_DEFER) { |
| if (PTR_ERR(gpiod) != -ENOENT) |
| pr_err("error getting GPIO for fixed link %pOF, proceed without\n", |
| fixed_link_node); |
| gpiod = NULL; |
| } |
| of_node_put(fixed_link_node); |
| |
| return gpiod; |
| } |
| #else |
| static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np) |
| { |
| return NULL; |
| } |
| #endif |
| |
| static struct phy_device *__fixed_phy_register(unsigned int irq, |
| struct fixed_phy_status *status, |
| struct device_node *np, |
| struct gpio_desc *gpiod) |
| { |
| struct fixed_mdio_bus *fmb = &platform_fmb; |
| struct phy_device *phy; |
| int phy_addr; |
| int ret; |
| |
| if (!fmb->mii_bus || fmb->mii_bus->state != MDIOBUS_REGISTERED) |
| return ERR_PTR(-EPROBE_DEFER); |
| |
| /* Check if we have a GPIO associated with this fixed phy */ |
| if (!gpiod) { |
| gpiod = fixed_phy_get_gpiod(np); |
| if (IS_ERR(gpiod)) |
| return ERR_CAST(gpiod); |
| } |
| |
| /* Get the next available PHY address, up to PHY_MAX_ADDR */ |
| phy_addr = ida_simple_get(&phy_fixed_ida, 0, PHY_MAX_ADDR, GFP_KERNEL); |
| if (phy_addr < 0) |
| return ERR_PTR(phy_addr); |
| |
| ret = fixed_phy_add_gpiod(irq, phy_addr, status, gpiod); |
| if (ret < 0) { |
| ida_simple_remove(&phy_fixed_ida, phy_addr); |
| return ERR_PTR(ret); |
| } |
| |
| phy = get_phy_device(fmb->mii_bus, phy_addr, false); |
| if (IS_ERR(phy)) { |
| fixed_phy_del(phy_addr); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| /* propagate the fixed link values to struct phy_device */ |
| phy->link = status->link; |
| if (status->link) { |
| phy->speed = status->speed; |
| phy->duplex = status->duplex; |
| phy->pause = status->pause; |
| phy->asym_pause = status->asym_pause; |
| } |
| |
| of_node_get(np); |
| phy->mdio.dev.of_node = np; |
| phy->is_pseudo_fixed_link = true; |
| |
| switch (status->speed) { |
| case SPEED_1000: |
| linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Half_BIT, |
| phy->supported); |
| linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT, |
| phy->supported); |
| /* fall through */ |
| case SPEED_100: |
| linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Half_BIT, |
| phy->supported); |
| linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Full_BIT, |
| phy->supported); |
| /* fall through */ |
| case SPEED_10: |
| default: |
| linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT, |
| phy->supported); |
| linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT, |
| phy->supported); |
| } |
| |
| phy_advertise_supported(phy); |
| |
| ret = phy_device_register(phy); |
| if (ret) { |
| phy_device_free(phy); |
| of_node_put(np); |
| fixed_phy_del(phy_addr); |
| return ERR_PTR(ret); |
| } |
| |
| return phy; |
| } |
| |
| struct phy_device *fixed_phy_register(unsigned int irq, |
| struct fixed_phy_status *status, |
| struct device_node *np) |
| { |
| return __fixed_phy_register(irq, status, np, NULL); |
| } |
| EXPORT_SYMBOL_GPL(fixed_phy_register); |
| |
| struct phy_device * |
| fixed_phy_register_with_gpiod(unsigned int irq, |
| struct fixed_phy_status *status, |
| struct gpio_desc *gpiod) |
| { |
| return __fixed_phy_register(irq, status, NULL, gpiod); |
| } |
| EXPORT_SYMBOL_GPL(fixed_phy_register_with_gpiod); |
| |
| void fixed_phy_unregister(struct phy_device *phy) |
| { |
| phy_device_remove(phy); |
| of_node_put(phy->mdio.dev.of_node); |
| fixed_phy_del(phy->mdio.addr); |
| } |
| EXPORT_SYMBOL_GPL(fixed_phy_unregister); |
| |
| static int __init fixed_mdio_bus_init(void) |
| { |
| struct fixed_mdio_bus *fmb = &platform_fmb; |
| int ret; |
| |
| pdev = platform_device_register_simple("Fixed MDIO bus", 0, NULL, 0); |
| if (IS_ERR(pdev)) |
| return PTR_ERR(pdev); |
| |
| fmb->mii_bus = mdiobus_alloc(); |
| if (fmb->mii_bus == NULL) { |
| ret = -ENOMEM; |
| goto err_mdiobus_reg; |
| } |
| |
| snprintf(fmb->mii_bus->id, MII_BUS_ID_SIZE, "fixed-0"); |
| fmb->mii_bus->name = "Fixed MDIO Bus"; |
| fmb->mii_bus->priv = fmb; |
| fmb->mii_bus->parent = &pdev->dev; |
| fmb->mii_bus->read = &fixed_mdio_read; |
| fmb->mii_bus->write = &fixed_mdio_write; |
| |
| ret = mdiobus_register(fmb->mii_bus); |
| if (ret) |
| goto err_mdiobus_alloc; |
| |
| return 0; |
| |
| err_mdiobus_alloc: |
| mdiobus_free(fmb->mii_bus); |
| err_mdiobus_reg: |
| platform_device_unregister(pdev); |
| return ret; |
| } |
| module_init(fixed_mdio_bus_init); |
| |
| static void __exit fixed_mdio_bus_exit(void) |
| { |
| struct fixed_mdio_bus *fmb = &platform_fmb; |
| struct fixed_phy *fp, *tmp; |
| |
| mdiobus_unregister(fmb->mii_bus); |
| mdiobus_free(fmb->mii_bus); |
| platform_device_unregister(pdev); |
| |
| list_for_each_entry_safe(fp, tmp, &fmb->phys, node) { |
| list_del(&fp->node); |
| kfree(fp); |
| } |
| ida_destroy(&phy_fixed_ida); |
| } |
| module_exit(fixed_mdio_bus_exit); |
| |
| MODULE_DESCRIPTION("Fixed MDIO bus (MDIO bus emulation with fixed PHYs)"); |
| MODULE_AUTHOR("Vitaly Bordug"); |
| MODULE_LICENSE("GPL"); |