// 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/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;	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; 			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; 			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; 	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_GPIOstatic 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 = fwnode_gpiod_get_index(of_fwnode_handle(fixed_link_node),				       "link", 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;}#elsestatic 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);		fallthrough;	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);		fallthrough;	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");