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 #include <linux/property.h> 25 26 void mdio_device_free(struct mdio_device *mdiodev) 27 { 28 put_device(&mdiodev->dev); 29 } 30 EXPORT_SYMBOL(mdio_device_free); 31 32 static void mdio_device_release(struct device *dev) 33 { 34 fwnode_handle_put(dev->fwnode); 35 kfree(to_mdio_device(dev)); 36 } 37 38 int mdio_device_bus_match(struct device *dev, struct device_driver *drv) 39 { 40 struct mdio_device *mdiodev = to_mdio_device(dev); 41 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 49 struct 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 66 dev_set_name(&mdiodev->dev, PHY_ID_FMT, bus->id, addr); 67 68 device_initialize(&mdiodev->dev); 69 70 return mdiodev; 71 } 72 EXPORT_SYMBOL(mdio_device_create); 73 74 /** 75 * mdio_device_register - Register the mdio device on the MDIO bus 76 * @mdiodev: mdio_device structure to be added to the MDIO bus 77 */ 78 int mdio_device_register(struct mdio_device *mdiodev) 79 { 80 int err; 81 82 dev_dbg(&mdiodev->dev, "%s\n", __func__); 83 84 err = mdiobus_register_device(mdiodev); 85 if (err) 86 return err; 87 88 err = device_add(&mdiodev->dev); 89 if (err) { 90 pr_err("MDIO %d failed to add\n", mdiodev->addr); 91 goto out; 92 } 93 94 return 0; 95 96 out: 97 mdiobus_unregister_device(mdiodev); 98 return err; 99 } 100 EXPORT_SYMBOL(mdio_device_register); 101 102 /** 103 * mdio_device_remove - Remove a previously registered mdio device from the 104 * MDIO bus 105 * @mdiodev: mdio_device structure to remove 106 * 107 * This doesn't free the mdio_device itself, it merely reverses the effects 108 * of mdio_device_register(). Use mdio_device_free() to free the device 109 * after calling this function. 110 */ 111 void mdio_device_remove(struct mdio_device *mdiodev) 112 { 113 device_del(&mdiodev->dev); 114 mdiobus_unregister_device(mdiodev); 115 } 116 EXPORT_SYMBOL(mdio_device_remove); 117 118 void mdio_device_reset(struct mdio_device *mdiodev, int value) 119 { 120 unsigned int d; 121 122 if (!mdiodev->reset_gpio && !mdiodev->reset_ctrl) 123 return; 124 125 if (mdiodev->reset_gpio) 126 gpiod_set_value_cansleep(mdiodev->reset_gpio, value); 127 128 if (mdiodev->reset_ctrl) { 129 if (value) 130 reset_control_assert(mdiodev->reset_ctrl); 131 else 132 reset_control_deassert(mdiodev->reset_ctrl); 133 } 134 135 d = value ? mdiodev->reset_assert_delay : mdiodev->reset_deassert_delay; 136 if (d) 137 fsleep(d); 138 } 139 EXPORT_SYMBOL(mdio_device_reset); 140 141 /** 142 * mdio_probe - probe an MDIO device 143 * @dev: device to probe 144 * 145 * Description: Take care of setting up the mdio_device structure 146 * and calling the driver to probe the device. 147 */ 148 static int mdio_probe(struct device *dev) 149 { 150 struct mdio_device *mdiodev = to_mdio_device(dev); 151 struct device_driver *drv = mdiodev->dev.driver; 152 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 153 int err = 0; 154 155 /* Deassert the reset signal */ 156 mdio_device_reset(mdiodev, 0); 157 158 if (mdiodrv->probe) { 159 err = mdiodrv->probe(mdiodev); 160 if (err) { 161 /* Assert the reset signal */ 162 mdio_device_reset(mdiodev, 1); 163 } 164 } 165 166 return err; 167 } 168 169 static int mdio_remove(struct device *dev) 170 { 171 struct mdio_device *mdiodev = to_mdio_device(dev); 172 struct device_driver *drv = mdiodev->dev.driver; 173 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 174 175 if (mdiodrv->remove) 176 mdiodrv->remove(mdiodev); 177 178 /* Assert the reset signal */ 179 mdio_device_reset(mdiodev, 1); 180 181 return 0; 182 } 183 184 static void mdio_shutdown(struct device *dev) 185 { 186 struct mdio_device *mdiodev = to_mdio_device(dev); 187 struct device_driver *drv = mdiodev->dev.driver; 188 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 189 190 if (mdiodrv->shutdown) 191 mdiodrv->shutdown(mdiodev); 192 } 193 194 /** 195 * mdio_driver_register - register an mdio_driver with the MDIO layer 196 * @drv: new mdio_driver to register 197 */ 198 int mdio_driver_register(struct mdio_driver *drv) 199 { 200 struct mdio_driver_common *mdiodrv = &drv->mdiodrv; 201 int retval; 202 203 pr_debug("%s: %s\n", __func__, mdiodrv->driver.name); 204 205 mdiodrv->driver.bus = &mdio_bus_type; 206 mdiodrv->driver.probe = mdio_probe; 207 mdiodrv->driver.remove = mdio_remove; 208 mdiodrv->driver.shutdown = mdio_shutdown; 209 210 retval = driver_register(&mdiodrv->driver); 211 if (retval) { 212 pr_err("%s: Error %d in registering driver\n", 213 mdiodrv->driver.name, retval); 214 215 return retval; 216 } 217 218 return 0; 219 } 220 EXPORT_SYMBOL(mdio_driver_register); 221 222 void mdio_driver_unregister(struct mdio_driver *drv) 223 { 224 struct mdio_driver_common *mdiodrv = &drv->mdiodrv; 225 226 driver_unregister(&mdiodrv->driver); 227 } 228 EXPORT_SYMBOL(mdio_driver_unregister); 229