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, 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 EXPORT_SYMBOL_GPL(mdio_device_bus_match); 49 50 struct mdio_device *mdio_device_create(struct mii_bus *bus, int addr) 51 { 52 struct mdio_device *mdiodev; 53 54 /* We allocate the device, and initialize the default values */ 55 mdiodev = kzalloc(sizeof(*mdiodev), GFP_KERNEL); 56 if (!mdiodev) 57 return ERR_PTR(-ENOMEM); 58 59 mdiodev->dev.release = mdio_device_release; 60 mdiodev->dev.parent = &bus->dev; 61 mdiodev->dev.bus = &mdio_bus_type; 62 mdiodev->device_free = mdio_device_free; 63 mdiodev->device_remove = mdio_device_remove; 64 mdiodev->bus = bus; 65 mdiodev->addr = addr; 66 mdiodev->reset_state = -1; 67 68 dev_set_name(&mdiodev->dev, PHY_ID_FMT, bus->id, addr); 69 70 device_initialize(&mdiodev->dev); 71 72 return mdiodev; 73 } 74 EXPORT_SYMBOL(mdio_device_create); 75 76 /** 77 * mdio_device_register - Register the mdio device on the MDIO bus 78 * @mdiodev: mdio_device structure to be added to the MDIO bus 79 */ 80 int mdio_device_register(struct mdio_device *mdiodev) 81 { 82 int err; 83 84 dev_dbg(&mdiodev->dev, "%s\n", __func__); 85 86 err = mdiobus_register_device(mdiodev); 87 if (err) 88 return err; 89 90 err = device_add(&mdiodev->dev); 91 if (err) { 92 pr_err("MDIO %d failed to add\n", mdiodev->addr); 93 goto out; 94 } 95 96 return 0; 97 98 out: 99 mdiobus_unregister_device(mdiodev); 100 return err; 101 } 102 EXPORT_SYMBOL(mdio_device_register); 103 104 /** 105 * mdio_device_remove - Remove a previously registered mdio device from the 106 * MDIO bus 107 * @mdiodev: mdio_device structure to remove 108 * 109 * This doesn't free the mdio_device itself, it merely reverses the effects 110 * of mdio_device_register(). Use mdio_device_free() to free the device 111 * after calling this function. 112 */ 113 void mdio_device_remove(struct mdio_device *mdiodev) 114 { 115 device_del(&mdiodev->dev); 116 mdiobus_unregister_device(mdiodev); 117 } 118 EXPORT_SYMBOL(mdio_device_remove); 119 120 void mdio_device_reset(struct mdio_device *mdiodev, int value) 121 { 122 unsigned int d; 123 124 if (!mdiodev->reset_gpio && !mdiodev->reset_ctrl) 125 return; 126 127 if (mdiodev->reset_state == value) 128 return; 129 130 if (mdiodev->reset_gpio) 131 gpiod_set_value_cansleep(mdiodev->reset_gpio, value); 132 133 if (mdiodev->reset_ctrl) { 134 if (value) 135 reset_control_assert(mdiodev->reset_ctrl); 136 else 137 reset_control_deassert(mdiodev->reset_ctrl); 138 } 139 140 d = value ? mdiodev->reset_assert_delay : mdiodev->reset_deassert_delay; 141 if (d) 142 fsleep(d); 143 144 mdiodev->reset_state = value; 145 } 146 EXPORT_SYMBOL(mdio_device_reset); 147 148 /** 149 * mdio_probe - probe an MDIO device 150 * @dev: device to probe 151 * 152 * Description: Take care of setting up the mdio_device structure 153 * and calling the driver to probe the device. 154 */ 155 static int mdio_probe(struct device *dev) 156 { 157 struct mdio_device *mdiodev = to_mdio_device(dev); 158 struct device_driver *drv = mdiodev->dev.driver; 159 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 160 int err = 0; 161 162 /* Deassert the reset signal */ 163 mdio_device_reset(mdiodev, 0); 164 165 if (mdiodrv->probe) { 166 err = mdiodrv->probe(mdiodev); 167 if (err) { 168 /* Assert the reset signal */ 169 mdio_device_reset(mdiodev, 1); 170 } 171 } 172 173 return err; 174 } 175 176 static int mdio_remove(struct device *dev) 177 { 178 struct mdio_device *mdiodev = to_mdio_device(dev); 179 struct device_driver *drv = mdiodev->dev.driver; 180 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 181 182 if (mdiodrv->remove) 183 mdiodrv->remove(mdiodev); 184 185 /* Assert the reset signal */ 186 mdio_device_reset(mdiodev, 1); 187 188 return 0; 189 } 190 191 static void mdio_shutdown(struct device *dev) 192 { 193 struct mdio_device *mdiodev = to_mdio_device(dev); 194 struct device_driver *drv = mdiodev->dev.driver; 195 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 196 197 if (mdiodrv->shutdown) 198 mdiodrv->shutdown(mdiodev); 199 } 200 201 /** 202 * mdio_driver_register - register an mdio_driver with the MDIO layer 203 * @drv: new mdio_driver to register 204 */ 205 int mdio_driver_register(struct mdio_driver *drv) 206 { 207 struct mdio_driver_common *mdiodrv = &drv->mdiodrv; 208 int retval; 209 210 pr_debug("%s: %s\n", __func__, mdiodrv->driver.name); 211 212 mdiodrv->driver.bus = &mdio_bus_type; 213 mdiodrv->driver.probe = mdio_probe; 214 mdiodrv->driver.remove = mdio_remove; 215 mdiodrv->driver.shutdown = mdio_shutdown; 216 217 retval = driver_register(&mdiodrv->driver); 218 if (retval) { 219 pr_err("%s: Error %d in registering driver\n", 220 mdiodrv->driver.name, retval); 221 222 return retval; 223 } 224 225 return 0; 226 } 227 EXPORT_SYMBOL(mdio_driver_register); 228 229 void mdio_driver_unregister(struct mdio_driver *drv) 230 { 231 struct mdio_driver_common *mdiodrv = &drv->mdiodrv; 232 233 driver_unregister(&mdiodrv->driver); 234 } 235 EXPORT_SYMBOL(mdio_driver_unregister); 236