1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * OF helpers for the MDIO (Ethernet PHY) API 4 * 5 * Copyright (c) 2009 Secret Lab Technologies, Ltd. 6 * 7 * This file provides helper functions for extracting PHY device information 8 * out of the OpenFirmware device tree and using it to populate an mii_bus. 9 */ 10 11 #include <linux/device.h> 12 #include <linux/err.h> 13 #include <linux/fwnode_mdio.h> 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/netdevice.h> 17 #include <linux/of.h> 18 #include <linux/of_irq.h> 19 #include <linux/of_mdio.h> 20 #include <linux/of_net.h> 21 #include <linux/phy.h> 22 #include <linux/phy_fixed.h> 23 24 #define DEFAULT_GPIO_RESET_DELAY 10 /* in microseconds */ 25 26 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>"); 27 MODULE_LICENSE("GPL"); 28 MODULE_DESCRIPTION("OpenFirmware MDIO bus (Ethernet PHY) accessors"); 29 30 /* Extract the clause 22 phy ID from the compatible string of the form 31 * ethernet-phy-idAAAA.BBBB */ 32 static int of_get_phy_id(struct device_node *device, u32 *phy_id) 33 { 34 return fwnode_get_phy_id(of_fwnode_handle(device), phy_id); 35 } 36 37 int of_mdiobus_phy_device_register(struct mii_bus *mdio, struct phy_device *phy, 38 struct device_node *child, u32 addr) 39 { 40 return fwnode_mdiobus_phy_device_register(mdio, phy, 41 of_fwnode_handle(child), 42 addr); 43 } 44 EXPORT_SYMBOL(of_mdiobus_phy_device_register); 45 46 static int of_mdiobus_register_phy(struct mii_bus *mdio, 47 struct device_node *child, u32 addr) 48 { 49 return fwnode_mdiobus_register_phy(mdio, of_fwnode_handle(child), addr); 50 } 51 52 static int of_mdiobus_register_device(struct mii_bus *mdio, 53 struct device_node *child, u32 addr) 54 { 55 struct fwnode_handle *fwnode = of_fwnode_handle(child); 56 struct mdio_device *mdiodev; 57 int rc; 58 59 mdiodev = mdio_device_create(mdio, addr); 60 if (IS_ERR(mdiodev)) 61 return PTR_ERR(mdiodev); 62 63 /* Associate the OF node with the device structure so it 64 * can be looked up later. 65 */ 66 fwnode_handle_get(fwnode); 67 device_set_node(&mdiodev->dev, fwnode); 68 69 /* All data is now stored in the mdiodev struct; register it. */ 70 rc = mdio_device_register(mdiodev); 71 if (rc) { 72 device_set_node(&mdiodev->dev, NULL); 73 fwnode_handle_put(fwnode); 74 mdio_device_free(mdiodev); 75 return rc; 76 } 77 78 dev_dbg(&mdio->dev, "registered mdio device %pOFn at address %i\n", 79 child, addr); 80 return 0; 81 } 82 83 /* The following is a list of PHY compatible strings which appear in 84 * some DTBs. The compatible string is never matched against a PHY 85 * driver, so is pointless. We only expect devices which are not PHYs 86 * to have a compatible string, so they can be matched to an MDIO 87 * driver. Encourage users to upgrade their DT blobs to remove these. 88 */ 89 static const struct of_device_id whitelist_phys[] = { 90 { .compatible = "brcm,40nm-ephy" }, 91 { .compatible = "broadcom,bcm5241" }, 92 { .compatible = "marvell,88E1111", }, 93 { .compatible = "marvell,88e1116", }, 94 { .compatible = "marvell,88e1118", }, 95 { .compatible = "marvell,88e1145", }, 96 { .compatible = "marvell,88e1149r", }, 97 { .compatible = "marvell,88e1310", }, 98 { .compatible = "marvell,88E1510", }, 99 { .compatible = "marvell,88E1514", }, 100 { .compatible = "moxa,moxart-rtl8201cp", }, 101 {} 102 }; 103 104 /* 105 * Return true if the child node is for a phy. It must either: 106 * o Compatible string of "ethernet-phy-idX.X" 107 * o Compatible string of "ethernet-phy-ieee802.3-c45" 108 * o Compatible string of "ethernet-phy-ieee802.3-c22" 109 * o In the white list above (and issue a warning) 110 * o No compatibility string 111 * 112 * A device which is not a phy is expected to have a compatible string 113 * indicating what sort of device it is. 114 */ 115 bool of_mdiobus_child_is_phy(struct device_node *child) 116 { 117 u32 phy_id; 118 119 if (of_get_phy_id(child, &phy_id) != -EINVAL) 120 return true; 121 122 if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45")) 123 return true; 124 125 if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22")) 126 return true; 127 128 if (of_match_node(whitelist_phys, child)) { 129 pr_warn(FW_WARN 130 "%pOF: Whitelisted compatible string. Please remove\n", 131 child); 132 return true; 133 } 134 135 if (!of_property_present(child, "compatible")) 136 return true; 137 138 return false; 139 } 140 EXPORT_SYMBOL(of_mdiobus_child_is_phy); 141 142 /** 143 * __of_mdiobus_register - Register mii_bus and create PHYs from the device tree 144 * @mdio: pointer to mii_bus structure 145 * @np: pointer to device_node of MDIO bus. 146 * @owner: module owning the @mdio object. 147 * 148 * This function registers the mii_bus structure and registers a phy_device 149 * for each child node of @np. 150 */ 151 int __of_mdiobus_register(struct mii_bus *mdio, struct device_node *np, 152 struct module *owner) 153 { 154 struct device_node *child; 155 bool scanphys = false; 156 int addr, rc; 157 158 if (!np) 159 return __mdiobus_register(mdio, owner); 160 161 /* Do not continue if the node is disabled */ 162 if (!of_device_is_available(np)) 163 return -ENODEV; 164 165 /* Mask out all PHYs from auto probing. Instead the PHYs listed in 166 * the device tree are populated after the bus has been registered */ 167 mdio->phy_mask = ~0; 168 169 device_set_node(&mdio->dev, of_fwnode_handle(np)); 170 171 /* Get bus level PHY reset GPIO details */ 172 mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY; 173 of_property_read_u32(np, "reset-delay-us", &mdio->reset_delay_us); 174 mdio->reset_post_delay_us = 0; 175 of_property_read_u32(np, "reset-post-delay-us", &mdio->reset_post_delay_us); 176 177 /* Register the MDIO bus */ 178 rc = __mdiobus_register(mdio, owner); 179 if (rc) 180 return rc; 181 182 /* Loop over the child nodes and register a phy_device for each phy */ 183 for_each_available_child_of_node(np, child) { 184 addr = of_mdio_parse_addr(&mdio->dev, child); 185 if (addr < 0) { 186 scanphys = true; 187 continue; 188 } 189 190 if (of_mdiobus_child_is_phy(child)) 191 rc = of_mdiobus_register_phy(mdio, child, addr); 192 else 193 rc = of_mdiobus_register_device(mdio, child, addr); 194 195 if (rc == -ENODEV) 196 dev_err(&mdio->dev, 197 "MDIO device at address %d is missing.\n", 198 addr); 199 else if (rc) 200 goto unregister; 201 } 202 203 if (!scanphys) 204 return 0; 205 206 /* auto scan for PHYs with empty reg property */ 207 for_each_available_child_of_node(np, child) { 208 /* Skip PHYs with reg property set */ 209 if (of_property_present(child, "reg")) 210 continue; 211 212 for (addr = 0; addr < PHY_MAX_ADDR; addr++) { 213 /* skip already registered PHYs */ 214 if (mdiobus_is_registered_device(mdio, addr)) 215 continue; 216 217 /* be noisy to encourage people to set reg property */ 218 dev_info(&mdio->dev, "scan phy %pOFn at address %i\n", 219 child, addr); 220 221 if (of_mdiobus_child_is_phy(child)) { 222 /* -ENODEV is the return code that PHYLIB has 223 * standardized on to indicate that bus 224 * scanning should continue. 225 */ 226 rc = of_mdiobus_register_phy(mdio, child, addr); 227 if (!rc) 228 break; 229 if (rc != -ENODEV) 230 goto unregister; 231 } 232 } 233 } 234 235 return 0; 236 237 unregister: 238 of_node_put(child); 239 mdiobus_unregister(mdio); 240 return rc; 241 } 242 EXPORT_SYMBOL(__of_mdiobus_register); 243 244 /** 245 * of_mdio_find_device - Given a device tree node, find the mdio_device 246 * @np: pointer to the mdio_device's device tree node 247 * 248 * If successful, returns a pointer to the mdio_device with the embedded 249 * struct device refcount incremented by one, or NULL on failure. 250 * The caller should call put_device() on the mdio_device after its use 251 */ 252 struct mdio_device *of_mdio_find_device(struct device_node *np) 253 { 254 return fwnode_mdio_find_device(of_fwnode_handle(np)); 255 } 256 EXPORT_SYMBOL(of_mdio_find_device); 257 258 /** 259 * of_phy_find_device - Give a PHY node, find the phy_device 260 * @phy_np: Pointer to the phy's device tree node 261 * 262 * If successful, returns a pointer to the phy_device with the embedded 263 * struct device refcount incremented by one, or NULL on failure. 264 */ 265 struct phy_device *of_phy_find_device(struct device_node *phy_np) 266 { 267 return fwnode_phy_find_device(of_fwnode_handle(phy_np)); 268 } 269 EXPORT_SYMBOL(of_phy_find_device); 270 271 /** 272 * of_phy_connect - Connect to the phy described in the device tree 273 * @dev: pointer to net_device claiming the phy 274 * @phy_np: Pointer to device tree node for the PHY 275 * @hndlr: Link state callback for the network device 276 * @flags: flags to pass to the PHY 277 * @iface: PHY data interface type 278 * 279 * If successful, returns a pointer to the phy_device with the embedded 280 * struct device refcount incremented by one, or NULL on failure. The 281 * refcount must be dropped by calling phy_disconnect() or phy_detach(). 282 */ 283 struct phy_device *of_phy_connect(struct net_device *dev, 284 struct device_node *phy_np, 285 void (*hndlr)(struct net_device *), u32 flags, 286 phy_interface_t iface) 287 { 288 struct phy_device *phy = of_phy_find_device(phy_np); 289 int ret; 290 291 if (!phy) 292 return NULL; 293 294 phy->dev_flags |= flags; 295 296 ret = phy_connect_direct(dev, phy, hndlr, iface); 297 298 /* refcount is held by phy_connect_direct() on success */ 299 put_device(&phy->mdio.dev); 300 301 return ret ? NULL : phy; 302 } 303 EXPORT_SYMBOL(of_phy_connect); 304 305 /** 306 * of_phy_get_and_connect 307 * - Get phy node and connect to the phy described in the device tree 308 * @dev: pointer to net_device claiming the phy 309 * @np: Pointer to device tree node for the net_device claiming the phy 310 * @hndlr: Link state callback for the network device 311 * 312 * If successful, returns a pointer to the phy_device with the embedded 313 * struct device refcount incremented by one, or NULL on failure. The 314 * refcount must be dropped by calling phy_disconnect() or phy_detach(). 315 */ 316 struct phy_device *of_phy_get_and_connect(struct net_device *dev, 317 struct device_node *np, 318 void (*hndlr)(struct net_device *)) 319 { 320 phy_interface_t iface; 321 struct device_node *phy_np; 322 struct phy_device *phy; 323 int ret; 324 325 ret = of_get_phy_mode(np, &iface); 326 if (ret) 327 return NULL; 328 if (of_phy_is_fixed_link(np)) { 329 ret = of_phy_register_fixed_link(np); 330 if (ret < 0) { 331 netdev_err(dev, "broken fixed-link specification\n"); 332 return NULL; 333 } 334 phy_np = of_node_get(np); 335 } else { 336 phy_np = of_parse_phandle(np, "phy-handle", 0); 337 if (!phy_np) 338 return NULL; 339 } 340 341 phy = of_phy_connect(dev, phy_np, hndlr, 0, iface); 342 343 of_node_put(phy_np); 344 345 return phy; 346 } 347 EXPORT_SYMBOL(of_phy_get_and_connect); 348 349 /* 350 * of_phy_is_fixed_link() and of_phy_register_fixed_link() must 351 * support two DT bindings: 352 * - the old DT binding, where 'fixed-link' was a property with 5 353 * cells encoding various information about the fixed PHY 354 * - the new DT binding, where 'fixed-link' is a sub-node of the 355 * Ethernet device. 356 */ 357 bool of_phy_is_fixed_link(struct device_node *np) 358 { 359 struct device_node *dn; 360 int len, err; 361 const char *managed; 362 363 /* New binding */ 364 dn = of_get_child_by_name(np, "fixed-link"); 365 if (dn) { 366 of_node_put(dn); 367 return true; 368 } 369 370 err = of_property_read_string(np, "managed", &managed); 371 if (err == 0 && strcmp(managed, "auto") != 0) 372 return true; 373 374 /* Old binding */ 375 if (of_get_property(np, "fixed-link", &len) && 376 len == (5 * sizeof(__be32))) 377 return true; 378 379 return false; 380 } 381 EXPORT_SYMBOL(of_phy_is_fixed_link); 382 383 int of_phy_register_fixed_link(struct device_node *np) 384 { 385 struct fixed_phy_status status = {}; 386 struct device_node *fixed_link_node; 387 u32 fixed_link_prop[5]; 388 const char *managed; 389 390 if (of_property_read_string(np, "managed", &managed) == 0 && 391 strcmp(managed, "in-band-status") == 0) { 392 /* status is zeroed, namely its .link member */ 393 goto register_phy; 394 } 395 396 /* New binding */ 397 fixed_link_node = of_get_child_by_name(np, "fixed-link"); 398 if (fixed_link_node) { 399 status.link = 1; 400 status.duplex = of_property_read_bool(fixed_link_node, 401 "full-duplex"); 402 if (of_property_read_u32(fixed_link_node, "speed", 403 &status.speed)) { 404 of_node_put(fixed_link_node); 405 return -EINVAL; 406 } 407 status.pause = of_property_read_bool(fixed_link_node, "pause"); 408 status.asym_pause = of_property_read_bool(fixed_link_node, 409 "asym-pause"); 410 of_node_put(fixed_link_node); 411 412 goto register_phy; 413 } 414 415 /* Old binding */ 416 if (of_property_read_u32_array(np, "fixed-link", fixed_link_prop, 417 ARRAY_SIZE(fixed_link_prop)) == 0) { 418 status.link = 1; 419 status.duplex = fixed_link_prop[1]; 420 status.speed = fixed_link_prop[2]; 421 status.pause = fixed_link_prop[3]; 422 status.asym_pause = fixed_link_prop[4]; 423 goto register_phy; 424 } 425 426 return -ENODEV; 427 428 register_phy: 429 return PTR_ERR_OR_ZERO(fixed_phy_register(PHY_POLL, &status, np)); 430 } 431 EXPORT_SYMBOL(of_phy_register_fixed_link); 432 433 void of_phy_deregister_fixed_link(struct device_node *np) 434 { 435 struct phy_device *phydev; 436 437 phydev = of_phy_find_device(np); 438 if (!phydev) 439 return; 440 441 fixed_phy_unregister(phydev); 442 443 put_device(&phydev->mdio.dev); /* of_phy_find_device() */ 444 phy_device_free(phydev); /* fixed_phy_register() */ 445 } 446 EXPORT_SYMBOL(of_phy_deregister_fixed_link); 447