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1// SPDX-License-Identifier: GPL-2.0+2/* Framework for MDIO devices, other than PHYs.3 *4 * Copyright (c) 2016 Andrew Lunn <andrew@lunn.ch>5 */6 7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt8 9#include <linux/delay.h>10#include <linux/errno.h>11#include <linux/gpio.h>12#include <linux/gpio/consumer.h>13#include <linux/init.h>14#include <linux/interrupt.h>15#include <linux/kernel.h>16#include <linux/mdio.h>17#include <linux/mii.h>18#include <linux/module.h>19#include <linux/phy.h>20#include <linux/reset.h>21#include <linux/slab.h>22#include <linux/string.h>23#include <linux/unistd.h>24#include <linux/property.h>25 26void mdio_device_free(struct mdio_device *mdiodev)27{28 put_device(&mdiodev->dev);29}30EXPORT_SYMBOL(mdio_device_free);31 32static void mdio_device_release(struct device *dev)33{34 fwnode_handle_put(dev->fwnode);35 kfree(to_mdio_device(dev));36}37 38int mdio_device_bus_match(struct device *dev, const struct device_driver *drv)39{40 struct mdio_device *mdiodev = to_mdio_device(dev);41 const struct mdio_driver *mdiodrv = to_mdio_driver(drv);42 43 if (mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY)44 return 0;45 46 return strcmp(mdiodev->modalias, drv->name) == 0;47}48 49struct mdio_device *mdio_device_create(struct mii_bus *bus, int addr)50{51 struct mdio_device *mdiodev;52 53 /* We allocate the device, and initialize the default values */54 mdiodev = kzalloc(sizeof(*mdiodev), GFP_KERNEL);55 if (!mdiodev)56 return ERR_PTR(-ENOMEM);57 58 mdiodev->dev.release = mdio_device_release;59 mdiodev->dev.parent = &bus->dev;60 mdiodev->dev.bus = &mdio_bus_type;61 mdiodev->device_free = mdio_device_free;62 mdiodev->device_remove = mdio_device_remove;63 mdiodev->bus = bus;64 mdiodev->addr = addr;65 mdiodev->reset_state = -1;66 67 dev_set_name(&mdiodev->dev, PHY_ID_FMT, bus->id, addr);68 69 device_initialize(&mdiodev->dev);70 71 return mdiodev;72}73EXPORT_SYMBOL(mdio_device_create);74 75/**76 * mdio_device_register - Register the mdio device on the MDIO bus77 * @mdiodev: mdio_device structure to be added to the MDIO bus78 */79int mdio_device_register(struct mdio_device *mdiodev)80{81 int err;82 83 dev_dbg(&mdiodev->dev, "%s\n", __func__);84 85 err = mdiobus_register_device(mdiodev);86 if (err)87 return err;88 89 err = device_add(&mdiodev->dev);90 if (err) {91 pr_err("MDIO %d failed to add\n", mdiodev->addr);92 goto out;93 }94 95 return 0;96 97 out:98 mdiobus_unregister_device(mdiodev);99 return err;100}101EXPORT_SYMBOL(mdio_device_register);102 103/**104 * mdio_device_remove - Remove a previously registered mdio device from the105 * MDIO bus106 * @mdiodev: mdio_device structure to remove107 *108 * This doesn't free the mdio_device itself, it merely reverses the effects109 * of mdio_device_register(). Use mdio_device_free() to free the device110 * after calling this function.111 */112void mdio_device_remove(struct mdio_device *mdiodev)113{114 device_del(&mdiodev->dev);115 mdiobus_unregister_device(mdiodev);116}117EXPORT_SYMBOL(mdio_device_remove);118 119void mdio_device_reset(struct mdio_device *mdiodev, int value)120{121 unsigned int d;122 123 if (!mdiodev->reset_gpio && !mdiodev->reset_ctrl)124 return;125 126 if (mdiodev->reset_state == value)127 return;128 129 if (mdiodev->reset_gpio)130 gpiod_set_value_cansleep(mdiodev->reset_gpio, value);131 132 if (mdiodev->reset_ctrl) {133 if (value)134 reset_control_assert(mdiodev->reset_ctrl);135 else136 reset_control_deassert(mdiodev->reset_ctrl);137 }138 139 d = value ? mdiodev->reset_assert_delay : mdiodev->reset_deassert_delay;140 if (d)141 fsleep(d);142 143 mdiodev->reset_state = value;144}145EXPORT_SYMBOL(mdio_device_reset);146 147/**148 * mdio_probe - probe an MDIO device149 * @dev: device to probe150 *151 * Description: Take care of setting up the mdio_device structure152 * and calling the driver to probe the device.153 */154static int mdio_probe(struct device *dev)155{156 struct mdio_device *mdiodev = to_mdio_device(dev);157 struct device_driver *drv = mdiodev->dev.driver;158 struct mdio_driver *mdiodrv = to_mdio_driver(drv);159 int err = 0;160 161 /* Deassert the reset signal */162 mdio_device_reset(mdiodev, 0);163 164 if (mdiodrv->probe) {165 err = mdiodrv->probe(mdiodev);166 if (err) {167 /* Assert the reset signal */168 mdio_device_reset(mdiodev, 1);169 }170 }171 172 return err;173}174 175static int mdio_remove(struct device *dev)176{177 struct mdio_device *mdiodev = to_mdio_device(dev);178 struct device_driver *drv = mdiodev->dev.driver;179 struct mdio_driver *mdiodrv = to_mdio_driver(drv);180 181 if (mdiodrv->remove)182 mdiodrv->remove(mdiodev);183 184 /* Assert the reset signal */185 mdio_device_reset(mdiodev, 1);186 187 return 0;188}189 190static void mdio_shutdown(struct device *dev)191{192 struct mdio_device *mdiodev = to_mdio_device(dev);193 struct device_driver *drv = mdiodev->dev.driver;194 struct mdio_driver *mdiodrv = to_mdio_driver(drv);195 196 if (mdiodrv->shutdown)197 mdiodrv->shutdown(mdiodev);198}199 200/**201 * mdio_driver_register - register an mdio_driver with the MDIO layer202 * @drv: new mdio_driver to register203 */204int mdio_driver_register(struct mdio_driver *drv)205{206 struct mdio_driver_common *mdiodrv = &drv->mdiodrv;207 int retval;208 209 pr_debug("%s: %s\n", __func__, mdiodrv->driver.name);210 211 mdiodrv->driver.bus = &mdio_bus_type;212 mdiodrv->driver.probe = mdio_probe;213 mdiodrv->driver.remove = mdio_remove;214 mdiodrv->driver.shutdown = mdio_shutdown;215 216 retval = driver_register(&mdiodrv->driver);217 if (retval) {218 pr_err("%s: Error %d in registering driver\n",219 mdiodrv->driver.name, retval);220 221 return retval;222 }223 224 return 0;225}226EXPORT_SYMBOL(mdio_driver_register);227 228void mdio_driver_unregister(struct mdio_driver *drv)229{230 struct mdio_driver_common *mdiodrv = &drv->mdiodrv;231 232 driver_unregister(&mdiodrv->driver);233}234EXPORT_SYMBOL(mdio_driver_unregister);235