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 ": " fmt 8 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 25 void mdio_device_free(struct mdio_device *mdiodev) 26 { 27 put_device(&mdiodev->dev); 28 } 29 EXPORT_SYMBOL(mdio_device_free); 30 31 static void mdio_device_release(struct device *dev) 32 { 33 kfree(to_mdio_device(dev)); 34 } 35 36 int mdio_device_bus_match(struct device *dev, struct device_driver *drv) 37 { 38 struct mdio_device *mdiodev = to_mdio_device(dev); 39 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 40 41 if (mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY) 42 return 0; 43 44 return strcmp(mdiodev->modalias, drv->name) == 0; 45 } 46 47 struct mdio_device *mdio_device_create(struct mii_bus *bus, int addr) 48 { 49 struct mdio_device *mdiodev; 50 51 /* We allocate the device, and initialize the default values */ 52 mdiodev = kzalloc(sizeof(*mdiodev), GFP_KERNEL); 53 if (!mdiodev) 54 return ERR_PTR(-ENOMEM); 55 56 mdiodev->dev.release = mdio_device_release; 57 mdiodev->dev.parent = &bus->dev; 58 mdiodev->dev.bus = &mdio_bus_type; 59 mdiodev->device_free = mdio_device_free; 60 mdiodev->device_remove = mdio_device_remove; 61 mdiodev->bus = bus; 62 mdiodev->addr = addr; 63 64 dev_set_name(&mdiodev->dev, PHY_ID_FMT, bus->id, addr); 65 66 device_initialize(&mdiodev->dev); 67 68 return mdiodev; 69 } 70 EXPORT_SYMBOL(mdio_device_create); 71 72 /** 73 * mdio_device_register - Register the mdio device on the MDIO bus 74 * @mdiodev: mdio_device structure to be added to the MDIO bus 75 */ 76 int mdio_device_register(struct mdio_device *mdiodev) 77 { 78 int err; 79 80 dev_dbg(&mdiodev->dev, "mdio_device_register\n"); 81 82 err = mdiobus_register_device(mdiodev); 83 if (err) 84 return err; 85 86 err = device_add(&mdiodev->dev); 87 if (err) { 88 pr_err("MDIO %d failed to add\n", mdiodev->addr); 89 goto out; 90 } 91 92 return 0; 93 94 out: 95 mdiobus_unregister_device(mdiodev); 96 return err; 97 } 98 EXPORT_SYMBOL(mdio_device_register); 99 100 /** 101 * mdio_device_remove - Remove a previously registered mdio device from the 102 * MDIO bus 103 * @mdiodev: mdio_device structure to remove 104 * 105 * This doesn't free the mdio_device itself, it merely reverses the effects 106 * of mdio_device_register(). Use mdio_device_free() to free the device 107 * after calling this function. 108 */ 109 void mdio_device_remove(struct mdio_device *mdiodev) 110 { 111 device_del(&mdiodev->dev); 112 mdiobus_unregister_device(mdiodev); 113 } 114 EXPORT_SYMBOL(mdio_device_remove); 115 116 void mdio_device_reset(struct mdio_device *mdiodev, int value) 117 { 118 unsigned int d; 119 120 if (!mdiodev->reset_gpio && !mdiodev->reset_ctrl) 121 return; 122 123 if (mdiodev->reset_gpio) 124 gpiod_set_value_cansleep(mdiodev->reset_gpio, value); 125 126 if (mdiodev->reset_ctrl) { 127 if (value) 128 reset_control_assert(mdiodev->reset_ctrl); 129 else 130 reset_control_deassert(mdiodev->reset_ctrl); 131 } 132 133 d = value ? mdiodev->reset_assert_delay : mdiodev->reset_deassert_delay; 134 if (d) 135 fsleep(d); 136 } 137 EXPORT_SYMBOL(mdio_device_reset); 138 139 /** 140 * mdio_probe - probe an MDIO device 141 * @dev: device to probe 142 * 143 * Description: Take care of setting up the mdio_device structure 144 * and calling the driver to probe the device. 145 */ 146 static int mdio_probe(struct device *dev) 147 { 148 struct mdio_device *mdiodev = to_mdio_device(dev); 149 struct device_driver *drv = mdiodev->dev.driver; 150 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 151 int err = 0; 152 153 /* Deassert the reset signal */ 154 mdio_device_reset(mdiodev, 0); 155 156 if (mdiodrv->probe) { 157 err = mdiodrv->probe(mdiodev); 158 if (err) { 159 /* Assert the reset signal */ 160 mdio_device_reset(mdiodev, 1); 161 } 162 } 163 164 return err; 165 } 166 167 static int mdio_remove(struct device *dev) 168 { 169 struct mdio_device *mdiodev = to_mdio_device(dev); 170 struct device_driver *drv = mdiodev->dev.driver; 171 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 172 173 if (mdiodrv->remove) 174 mdiodrv->remove(mdiodev); 175 176 /* Assert the reset signal */ 177 mdio_device_reset(mdiodev, 1); 178 179 return 0; 180 } 181 182 /** 183 * mdio_driver_register - register an mdio_driver with the MDIO layer 184 * @drv: new mdio_driver to register 185 */ 186 int mdio_driver_register(struct mdio_driver *drv) 187 { 188 struct mdio_driver_common *mdiodrv = &drv->mdiodrv; 189 int retval; 190 191 pr_debug("mdio_driver_register: %s\n", mdiodrv->driver.name); 192 193 mdiodrv->driver.bus = &mdio_bus_type; 194 mdiodrv->driver.probe = mdio_probe; 195 mdiodrv->driver.remove = mdio_remove; 196 197 retval = driver_register(&mdiodrv->driver); 198 if (retval) { 199 pr_err("%s: Error %d in registering driver\n", 200 mdiodrv->driver.name, retval); 201 202 return retval; 203 } 204 205 return 0; 206 } 207 EXPORT_SYMBOL(mdio_driver_register); 208 209 void mdio_driver_unregister(struct mdio_driver *drv) 210 { 211 struct mdio_driver_common *mdiodrv = &drv->mdiodrv; 212 213 driver_unregister(&mdiodrv->driver); 214 } 215 EXPORT_SYMBOL(mdio_driver_unregister); 216