1 /* 2 * drivers/net/phy/mdio_bus.c 3 * 4 * MDIO Bus interface 5 * 6 * Author: Andy Fleming 7 * 8 * Copyright (c) 2004 Freescale Semiconductor, Inc. 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License as published by the 12 * Free Software Foundation; either version 2 of the License, or (at your 13 * option) any later version. 14 * 15 */ 16 #include <linux/kernel.h> 17 #include <linux/string.h> 18 #include <linux/errno.h> 19 #include <linux/unistd.h> 20 #include <linux/slab.h> 21 #include <linux/interrupt.h> 22 #include <linux/init.h> 23 #include <linux/delay.h> 24 #include <linux/netdevice.h> 25 #include <linux/etherdevice.h> 26 #include <linux/skbuff.h> 27 #include <linux/spinlock.h> 28 #include <linux/mm.h> 29 #include <linux/module.h> 30 #include <linux/mii.h> 31 #include <linux/ethtool.h> 32 #include <linux/phy.h> 33 34 #include <asm/io.h> 35 #include <asm/irq.h> 36 #include <asm/uaccess.h> 37 38 /** 39 * mdiobus_alloc - allocate a mii_bus structure 40 * 41 * Description: called by a bus driver to allocate an mii_bus 42 * structure to fill in. 43 */ 44 struct mii_bus *mdiobus_alloc(void) 45 { 46 struct mii_bus *bus; 47 48 bus = kzalloc(sizeof(*bus), GFP_KERNEL); 49 if (bus != NULL) 50 bus->state = MDIOBUS_ALLOCATED; 51 52 return bus; 53 } 54 EXPORT_SYMBOL(mdiobus_alloc); 55 56 /** 57 * mdiobus_release - mii_bus device release callback 58 * @d: the target struct device that contains the mii_bus 59 * 60 * Description: called when the last reference to an mii_bus is 61 * dropped, to free the underlying memory. 62 */ 63 static void mdiobus_release(struct device *d) 64 { 65 struct mii_bus *bus = to_mii_bus(d); 66 BUG_ON(bus->state != MDIOBUS_RELEASED && 67 /* for compatibility with error handling in drivers */ 68 bus->state != MDIOBUS_ALLOCATED); 69 kfree(bus); 70 } 71 72 static struct class mdio_bus_class = { 73 .name = "mdio_bus", 74 .dev_release = mdiobus_release, 75 }; 76 77 /** 78 * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus 79 * @bus: target mii_bus 80 * 81 * Description: Called by a bus driver to bring up all the PHYs 82 * on a given bus, and attach them to the bus. 83 * 84 * Returns 0 on success or < 0 on error. 85 */ 86 int mdiobus_register(struct mii_bus *bus) 87 { 88 int i, err; 89 90 if (NULL == bus || NULL == bus->name || 91 NULL == bus->read || 92 NULL == bus->write) 93 return -EINVAL; 94 95 BUG_ON(bus->state != MDIOBUS_ALLOCATED && 96 bus->state != MDIOBUS_UNREGISTERED); 97 98 bus->dev.parent = bus->parent; 99 bus->dev.class = &mdio_bus_class; 100 bus->dev.groups = NULL; 101 dev_set_name(&bus->dev, bus->id); 102 103 err = device_register(&bus->dev); 104 if (err) { 105 printk(KERN_ERR "mii_bus %s failed to register\n", bus->id); 106 return -EINVAL; 107 } 108 109 mutex_init(&bus->mdio_lock); 110 111 if (bus->reset) 112 bus->reset(bus); 113 114 for (i = 0; i < PHY_MAX_ADDR; i++) { 115 bus->phy_map[i] = NULL; 116 if ((bus->phy_mask & (1 << i)) == 0) { 117 struct phy_device *phydev; 118 119 phydev = mdiobus_scan(bus, i); 120 if (IS_ERR(phydev)) { 121 err = PTR_ERR(phydev); 122 goto error; 123 } 124 } 125 } 126 127 bus->state = MDIOBUS_REGISTERED; 128 pr_info("%s: probed\n", bus->name); 129 return 0; 130 131 error: 132 while (--i >= 0) { 133 if (bus->phy_map[i]) 134 device_unregister(&bus->phy_map[i]->dev); 135 } 136 device_del(&bus->dev); 137 return err; 138 } 139 EXPORT_SYMBOL(mdiobus_register); 140 141 void mdiobus_unregister(struct mii_bus *bus) 142 { 143 int i; 144 145 BUG_ON(bus->state != MDIOBUS_REGISTERED); 146 bus->state = MDIOBUS_UNREGISTERED; 147 148 device_del(&bus->dev); 149 for (i = 0; i < PHY_MAX_ADDR; i++) { 150 if (bus->phy_map[i]) 151 device_unregister(&bus->phy_map[i]->dev); 152 } 153 } 154 EXPORT_SYMBOL(mdiobus_unregister); 155 156 /** 157 * mdiobus_free - free a struct mii_bus 158 * @bus: mii_bus to free 159 * 160 * This function releases the reference to the underlying device 161 * object in the mii_bus. If this is the last reference, the mii_bus 162 * will be freed. 163 */ 164 void mdiobus_free(struct mii_bus *bus) 165 { 166 /* 167 * For compatibility with error handling in drivers. 168 */ 169 if (bus->state == MDIOBUS_ALLOCATED) { 170 kfree(bus); 171 return; 172 } 173 174 BUG_ON(bus->state != MDIOBUS_UNREGISTERED); 175 bus->state = MDIOBUS_RELEASED; 176 177 put_device(&bus->dev); 178 } 179 EXPORT_SYMBOL(mdiobus_free); 180 181 struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr) 182 { 183 struct phy_device *phydev; 184 int err; 185 186 phydev = get_phy_device(bus, addr); 187 if (IS_ERR(phydev) || phydev == NULL) 188 return phydev; 189 190 /* There's a PHY at this address 191 * We need to set: 192 * 1) IRQ 193 * 2) bus_id 194 * 3) parent 195 * 4) bus 196 * 5) mii_bus 197 * And, we need to register it */ 198 199 phydev->irq = bus->irq != NULL ? bus->irq[addr] : PHY_POLL; 200 201 phydev->dev.parent = bus->parent; 202 phydev->dev.bus = &mdio_bus_type; 203 dev_set_name(&phydev->dev, PHY_ID_FMT, bus->id, addr); 204 205 phydev->bus = bus; 206 207 /* Run all of the fixups for this PHY */ 208 phy_scan_fixups(phydev); 209 210 err = device_register(&phydev->dev); 211 if (err) { 212 printk(KERN_ERR "phy %d failed to register\n", addr); 213 phy_device_free(phydev); 214 phydev = NULL; 215 } 216 217 bus->phy_map[addr] = phydev; 218 219 return phydev; 220 } 221 EXPORT_SYMBOL(mdiobus_scan); 222 223 /** 224 * mdiobus_read - Convenience function for reading a given MII mgmt register 225 * @bus: the mii_bus struct 226 * @addr: the phy address 227 * @regnum: register number to read 228 * 229 * NOTE: MUST NOT be called from interrupt context, 230 * because the bus read/write functions may wait for an interrupt 231 * to conclude the operation. 232 */ 233 int mdiobus_read(struct mii_bus *bus, int addr, u16 regnum) 234 { 235 int retval; 236 237 BUG_ON(in_interrupt()); 238 239 mutex_lock(&bus->mdio_lock); 240 retval = bus->read(bus, addr, regnum); 241 mutex_unlock(&bus->mdio_lock); 242 243 return retval; 244 } 245 EXPORT_SYMBOL(mdiobus_read); 246 247 /** 248 * mdiobus_write - Convenience function for writing a given MII mgmt register 249 * @bus: the mii_bus struct 250 * @addr: the phy address 251 * @regnum: register number to write 252 * @val: value to write to @regnum 253 * 254 * NOTE: MUST NOT be called from interrupt context, 255 * because the bus read/write functions may wait for an interrupt 256 * to conclude the operation. 257 */ 258 int mdiobus_write(struct mii_bus *bus, int addr, u16 regnum, u16 val) 259 { 260 int err; 261 262 BUG_ON(in_interrupt()); 263 264 mutex_lock(&bus->mdio_lock); 265 err = bus->write(bus, addr, regnum, val); 266 mutex_unlock(&bus->mdio_lock); 267 268 return err; 269 } 270 EXPORT_SYMBOL(mdiobus_write); 271 272 /** 273 * mdio_bus_match - determine if given PHY driver supports the given PHY device 274 * @dev: target PHY device 275 * @drv: given PHY driver 276 * 277 * Description: Given a PHY device, and a PHY driver, return 1 if 278 * the driver supports the device. Otherwise, return 0. 279 */ 280 static int mdio_bus_match(struct device *dev, struct device_driver *drv) 281 { 282 struct phy_device *phydev = to_phy_device(dev); 283 struct phy_driver *phydrv = to_phy_driver(drv); 284 285 return ((phydrv->phy_id & phydrv->phy_id_mask) == 286 (phydev->phy_id & phydrv->phy_id_mask)); 287 } 288 289 /* Suspend and resume. Copied from platform_suspend and 290 * platform_resume 291 */ 292 static int mdio_bus_suspend(struct device * dev, pm_message_t state) 293 { 294 int ret = 0; 295 struct device_driver *drv = dev->driver; 296 struct phy_driver *phydrv = to_phy_driver(drv); 297 struct phy_device *phydev = to_phy_device(dev); 298 299 if ((!device_may_wakeup(phydev->dev.parent)) && 300 (phydrv && phydrv->suspend)) 301 ret = phydrv->suspend(phydev); 302 303 return ret; 304 } 305 306 static int mdio_bus_resume(struct device * dev) 307 { 308 int ret = 0; 309 struct device_driver *drv = dev->driver; 310 struct phy_driver *phydrv = to_phy_driver(drv); 311 struct phy_device *phydev = to_phy_device(dev); 312 313 if ((!device_may_wakeup(phydev->dev.parent)) && 314 (phydrv && phydrv->resume)) 315 ret = phydrv->resume(phydev); 316 317 return ret; 318 } 319 320 struct bus_type mdio_bus_type = { 321 .name = "mdio_bus", 322 .match = mdio_bus_match, 323 .suspend = mdio_bus_suspend, 324 .resume = mdio_bus_resume, 325 }; 326 EXPORT_SYMBOL(mdio_bus_type); 327 328 int __init mdio_bus_init(void) 329 { 330 int ret; 331 332 ret = class_register(&mdio_bus_class); 333 if (!ret) { 334 ret = bus_register(&mdio_bus_type); 335 if (ret) 336 class_unregister(&mdio_bus_class); 337 } 338 339 return ret; 340 } 341 342 void mdio_bus_exit(void) 343 { 344 class_unregister(&mdio_bus_class); 345 bus_unregister(&mdio_bus_type); 346 } 347