1 /* 2 * Fixed MDIO bus (MDIO bus emulation with fixed PHYs) 3 * 4 * Author: Vitaly Bordug <vbordug@ru.mvista.com> 5 * Anton Vorontsov <avorontsov@ru.mvista.com> 6 * 7 * Copyright (c) 2006-2007 MontaVista Software, Inc. 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the 11 * Free Software Foundation; either version 2 of the License, or (at your 12 * option) any later version. 13 */ 14 15 #include <linux/kernel.h> 16 #include <linux/module.h> 17 #include <linux/platform_device.h> 18 #include <linux/list.h> 19 #include <linux/mii.h> 20 #include <linux/phy.h> 21 #include <linux/phy_fixed.h> 22 #include <linux/err.h> 23 #include <linux/slab.h> 24 #include <linux/of.h> 25 26 #define MII_REGS_NUM 29 27 28 struct fixed_mdio_bus { 29 int irqs[PHY_MAX_ADDR]; 30 struct mii_bus *mii_bus; 31 struct list_head phys; 32 }; 33 34 struct fixed_phy { 35 int addr; 36 u16 regs[MII_REGS_NUM]; 37 struct phy_device *phydev; 38 struct fixed_phy_status status; 39 int (*link_update)(struct net_device *, struct fixed_phy_status *); 40 struct list_head node; 41 }; 42 43 static struct platform_device *pdev; 44 static struct fixed_mdio_bus platform_fmb = { 45 .phys = LIST_HEAD_INIT(platform_fmb.phys), 46 }; 47 48 static int fixed_phy_update_regs(struct fixed_phy *fp) 49 { 50 u16 bmsr = BMSR_ANEGCAPABLE; 51 u16 bmcr = 0; 52 u16 lpagb = 0; 53 u16 lpa = 0; 54 55 if (!fp->status.link) 56 goto done; 57 bmsr |= BMSR_LSTATUS | BMSR_ANEGCOMPLETE; 58 59 if (fp->status.duplex) { 60 bmcr |= BMCR_FULLDPLX; 61 62 switch (fp->status.speed) { 63 case 1000: 64 bmsr |= BMSR_ESTATEN; 65 bmcr |= BMCR_SPEED1000; 66 lpagb |= LPA_1000FULL; 67 break; 68 case 100: 69 bmsr |= BMSR_100FULL; 70 bmcr |= BMCR_SPEED100; 71 lpa |= LPA_100FULL; 72 break; 73 case 10: 74 bmsr |= BMSR_10FULL; 75 lpa |= LPA_10FULL; 76 break; 77 default: 78 pr_warn("fixed phy: unknown speed\n"); 79 return -EINVAL; 80 } 81 } else { 82 switch (fp->status.speed) { 83 case 1000: 84 bmsr |= BMSR_ESTATEN; 85 bmcr |= BMCR_SPEED1000; 86 lpagb |= LPA_1000HALF; 87 break; 88 case 100: 89 bmsr |= BMSR_100HALF; 90 bmcr |= BMCR_SPEED100; 91 lpa |= LPA_100HALF; 92 break; 93 case 10: 94 bmsr |= BMSR_10HALF; 95 lpa |= LPA_10HALF; 96 break; 97 default: 98 pr_warn("fixed phy: unknown speed\n"); 99 return -EINVAL; 100 } 101 } 102 103 if (fp->status.pause) 104 lpa |= LPA_PAUSE_CAP; 105 106 if (fp->status.asym_pause) 107 lpa |= LPA_PAUSE_ASYM; 108 109 done: 110 fp->regs[MII_PHYSID1] = 0; 111 fp->regs[MII_PHYSID2] = 0; 112 113 fp->regs[MII_BMSR] = bmsr; 114 fp->regs[MII_BMCR] = bmcr; 115 fp->regs[MII_LPA] = lpa; 116 fp->regs[MII_STAT1000] = lpagb; 117 118 return 0; 119 } 120 121 static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num) 122 { 123 struct fixed_mdio_bus *fmb = bus->priv; 124 struct fixed_phy *fp; 125 126 if (reg_num >= MII_REGS_NUM) 127 return -1; 128 129 /* We do not support emulating Clause 45 over Clause 22 register reads 130 * return an error instead of bogus data. 131 */ 132 switch (reg_num) { 133 case MII_MMD_CTRL: 134 case MII_MMD_DATA: 135 return -1; 136 default: 137 break; 138 } 139 140 list_for_each_entry(fp, &fmb->phys, node) { 141 if (fp->addr == phy_addr) { 142 /* Issue callback if user registered it. */ 143 if (fp->link_update) { 144 fp->link_update(fp->phydev->attached_dev, 145 &fp->status); 146 fixed_phy_update_regs(fp); 147 } 148 return fp->regs[reg_num]; 149 } 150 } 151 152 return 0xFFFF; 153 } 154 155 static int fixed_mdio_write(struct mii_bus *bus, int phy_addr, int reg_num, 156 u16 val) 157 { 158 return 0; 159 } 160 161 /* 162 * If something weird is required to be done with link/speed, 163 * network driver is able to assign a function to implement this. 164 * May be useful for PHY's that need to be software-driven. 165 */ 166 int fixed_phy_set_link_update(struct phy_device *phydev, 167 int (*link_update)(struct net_device *, 168 struct fixed_phy_status *)) 169 { 170 struct fixed_mdio_bus *fmb = &platform_fmb; 171 struct fixed_phy *fp; 172 173 if (!phydev || !phydev->bus) 174 return -EINVAL; 175 176 list_for_each_entry(fp, &fmb->phys, node) { 177 if (fp->addr == phydev->addr) { 178 fp->link_update = link_update; 179 fp->phydev = phydev; 180 return 0; 181 } 182 } 183 184 return -ENOENT; 185 } 186 EXPORT_SYMBOL_GPL(fixed_phy_set_link_update); 187 188 int fixed_phy_update_state(struct phy_device *phydev, 189 const struct fixed_phy_status *status, 190 const struct fixed_phy_status *changed) 191 { 192 struct fixed_mdio_bus *fmb = &platform_fmb; 193 struct fixed_phy *fp; 194 195 if (!phydev || !phydev->bus) 196 return -EINVAL; 197 198 list_for_each_entry(fp, &fmb->phys, node) { 199 if (fp->addr == phydev->addr) { 200 #define _UPD(x) if (changed->x) \ 201 fp->status.x = status->x 202 _UPD(link); 203 _UPD(speed); 204 _UPD(duplex); 205 _UPD(pause); 206 _UPD(asym_pause); 207 #undef _UPD 208 fixed_phy_update_regs(fp); 209 return 0; 210 } 211 } 212 213 return -ENOENT; 214 } 215 EXPORT_SYMBOL(fixed_phy_update_state); 216 217 int fixed_phy_add(unsigned int irq, int phy_addr, 218 struct fixed_phy_status *status) 219 { 220 int ret; 221 struct fixed_mdio_bus *fmb = &platform_fmb; 222 struct fixed_phy *fp; 223 224 fp = kzalloc(sizeof(*fp), GFP_KERNEL); 225 if (!fp) 226 return -ENOMEM; 227 228 memset(fp->regs, 0xFF, sizeof(fp->regs[0]) * MII_REGS_NUM); 229 230 fmb->irqs[phy_addr] = irq; 231 232 fp->addr = phy_addr; 233 fp->status = *status; 234 235 ret = fixed_phy_update_regs(fp); 236 if (ret) 237 goto err_regs; 238 239 list_add_tail(&fp->node, &fmb->phys); 240 241 return 0; 242 243 err_regs: 244 kfree(fp); 245 return ret; 246 } 247 EXPORT_SYMBOL_GPL(fixed_phy_add); 248 249 void fixed_phy_del(int phy_addr) 250 { 251 struct fixed_mdio_bus *fmb = &platform_fmb; 252 struct fixed_phy *fp, *tmp; 253 254 list_for_each_entry_safe(fp, tmp, &fmb->phys, node) { 255 if (fp->addr == phy_addr) { 256 list_del(&fp->node); 257 kfree(fp); 258 return; 259 } 260 } 261 } 262 EXPORT_SYMBOL_GPL(fixed_phy_del); 263 264 static int phy_fixed_addr; 265 static DEFINE_SPINLOCK(phy_fixed_addr_lock); 266 267 struct phy_device *fixed_phy_register(unsigned int irq, 268 struct fixed_phy_status *status, 269 struct device_node *np) 270 { 271 struct fixed_mdio_bus *fmb = &platform_fmb; 272 struct phy_device *phy; 273 int phy_addr; 274 int ret; 275 276 /* Get the next available PHY address, up to PHY_MAX_ADDR */ 277 spin_lock(&phy_fixed_addr_lock); 278 if (phy_fixed_addr == PHY_MAX_ADDR) { 279 spin_unlock(&phy_fixed_addr_lock); 280 return ERR_PTR(-ENOSPC); 281 } 282 phy_addr = phy_fixed_addr++; 283 spin_unlock(&phy_fixed_addr_lock); 284 285 ret = fixed_phy_add(PHY_POLL, phy_addr, status); 286 if (ret < 0) 287 return ERR_PTR(ret); 288 289 phy = get_phy_device(fmb->mii_bus, phy_addr, false); 290 if (!phy || IS_ERR(phy)) { 291 fixed_phy_del(phy_addr); 292 return ERR_PTR(-EINVAL); 293 } 294 295 of_node_get(np); 296 phy->dev.of_node = np; 297 298 ret = phy_device_register(phy); 299 if (ret) { 300 phy_device_free(phy); 301 of_node_put(np); 302 fixed_phy_del(phy_addr); 303 return ERR_PTR(ret); 304 } 305 306 return phy; 307 } 308 EXPORT_SYMBOL_GPL(fixed_phy_register); 309 310 static int __init fixed_mdio_bus_init(void) 311 { 312 struct fixed_mdio_bus *fmb = &platform_fmb; 313 int ret; 314 315 pdev = platform_device_register_simple("Fixed MDIO bus", 0, NULL, 0); 316 if (IS_ERR(pdev)) { 317 ret = PTR_ERR(pdev); 318 goto err_pdev; 319 } 320 321 fmb->mii_bus = mdiobus_alloc(); 322 if (fmb->mii_bus == NULL) { 323 ret = -ENOMEM; 324 goto err_mdiobus_reg; 325 } 326 327 snprintf(fmb->mii_bus->id, MII_BUS_ID_SIZE, "fixed-0"); 328 fmb->mii_bus->name = "Fixed MDIO Bus"; 329 fmb->mii_bus->priv = fmb; 330 fmb->mii_bus->parent = &pdev->dev; 331 fmb->mii_bus->read = &fixed_mdio_read; 332 fmb->mii_bus->write = &fixed_mdio_write; 333 fmb->mii_bus->irq = fmb->irqs; 334 335 ret = mdiobus_register(fmb->mii_bus); 336 if (ret) 337 goto err_mdiobus_alloc; 338 339 return 0; 340 341 err_mdiobus_alloc: 342 mdiobus_free(fmb->mii_bus); 343 err_mdiobus_reg: 344 platform_device_unregister(pdev); 345 err_pdev: 346 return ret; 347 } 348 module_init(fixed_mdio_bus_init); 349 350 static void __exit fixed_mdio_bus_exit(void) 351 { 352 struct fixed_mdio_bus *fmb = &platform_fmb; 353 struct fixed_phy *fp, *tmp; 354 355 mdiobus_unregister(fmb->mii_bus); 356 mdiobus_free(fmb->mii_bus); 357 platform_device_unregister(pdev); 358 359 list_for_each_entry_safe(fp, tmp, &fmb->phys, node) { 360 list_del(&fp->node); 361 kfree(fp); 362 } 363 } 364 module_exit(fixed_mdio_bus_exit); 365 366 MODULE_DESCRIPTION("Fixed MDIO bus (MDIO bus emulation with fixed PHYs)"); 367 MODULE_AUTHOR("Vitaly Bordug"); 368 MODULE_LICENSE("GPL"); 369