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.duplex) { 56 bmcr |= BMCR_FULLDPLX; 57 58 switch (fp->status.speed) { 59 case 1000: 60 bmsr |= BMSR_ESTATEN; 61 bmcr |= BMCR_SPEED1000; 62 lpagb |= LPA_1000FULL; 63 break; 64 case 100: 65 bmsr |= BMSR_100FULL; 66 bmcr |= BMCR_SPEED100; 67 lpa |= LPA_100FULL; 68 break; 69 case 10: 70 bmsr |= BMSR_10FULL; 71 lpa |= LPA_10FULL; 72 break; 73 default: 74 pr_warn("fixed phy: unknown speed\n"); 75 return -EINVAL; 76 } 77 } else { 78 switch (fp->status.speed) { 79 case 1000: 80 bmsr |= BMSR_ESTATEN; 81 bmcr |= BMCR_SPEED1000; 82 lpagb |= LPA_1000HALF; 83 break; 84 case 100: 85 bmsr |= BMSR_100HALF; 86 bmcr |= BMCR_SPEED100; 87 lpa |= LPA_100HALF; 88 break; 89 case 10: 90 bmsr |= BMSR_10HALF; 91 lpa |= LPA_10HALF; 92 break; 93 default: 94 pr_warn("fixed phy: unknown speed\n"); 95 return -EINVAL; 96 } 97 } 98 99 if (fp->status.link) 100 bmsr |= BMSR_LSTATUS | BMSR_ANEGCOMPLETE; 101 102 if (fp->status.pause) 103 lpa |= LPA_PAUSE_CAP; 104 105 if (fp->status.asym_pause) 106 lpa |= LPA_PAUSE_ASYM; 107 108 fp->regs[MII_PHYSID1] = 0; 109 fp->regs[MII_PHYSID2] = 0; 110 111 fp->regs[MII_BMSR] = bmsr; 112 fp->regs[MII_BMCR] = bmcr; 113 fp->regs[MII_LPA] = lpa; 114 fp->regs[MII_STAT1000] = lpagb; 115 116 return 0; 117 } 118 119 static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num) 120 { 121 struct fixed_mdio_bus *fmb = bus->priv; 122 struct fixed_phy *fp; 123 124 if (reg_num >= MII_REGS_NUM) 125 return -1; 126 127 /* We do not support emulating Clause 45 over Clause 22 register reads 128 * return an error instead of bogus data. 129 */ 130 switch (reg_num) { 131 case MII_MMD_CTRL: 132 case MII_MMD_DATA: 133 return -1; 134 default: 135 break; 136 } 137 138 list_for_each_entry(fp, &fmb->phys, node) { 139 if (fp->addr == phy_addr) { 140 /* Issue callback if user registered it. */ 141 if (fp->link_update) { 142 fp->link_update(fp->phydev->attached_dev, 143 &fp->status); 144 fixed_phy_update_regs(fp); 145 } 146 return fp->regs[reg_num]; 147 } 148 } 149 150 return 0xFFFF; 151 } 152 153 static int fixed_mdio_write(struct mii_bus *bus, int phy_addr, int reg_num, 154 u16 val) 155 { 156 return 0; 157 } 158 159 /* 160 * If something weird is required to be done with link/speed, 161 * network driver is able to assign a function to implement this. 162 * May be useful for PHY's that need to be software-driven. 163 */ 164 int fixed_phy_set_link_update(struct phy_device *phydev, 165 int (*link_update)(struct net_device *, 166 struct fixed_phy_status *)) 167 { 168 struct fixed_mdio_bus *fmb = &platform_fmb; 169 struct fixed_phy *fp; 170 171 if (!link_update || !phydev || !phydev->bus) 172 return -EINVAL; 173 174 list_for_each_entry(fp, &fmb->phys, node) { 175 if (fp->addr == phydev->addr) { 176 fp->link_update = link_update; 177 fp->phydev = phydev; 178 return 0; 179 } 180 } 181 182 return -ENOENT; 183 } 184 EXPORT_SYMBOL_GPL(fixed_phy_set_link_update); 185 186 int fixed_phy_add(unsigned int irq, int phy_addr, 187 struct fixed_phy_status *status) 188 { 189 int ret; 190 struct fixed_mdio_bus *fmb = &platform_fmb; 191 struct fixed_phy *fp; 192 193 fp = kzalloc(sizeof(*fp), GFP_KERNEL); 194 if (!fp) 195 return -ENOMEM; 196 197 memset(fp->regs, 0xFF, sizeof(fp->regs[0]) * MII_REGS_NUM); 198 199 fmb->irqs[phy_addr] = irq; 200 201 fp->addr = phy_addr; 202 fp->status = *status; 203 204 ret = fixed_phy_update_regs(fp); 205 if (ret) 206 goto err_regs; 207 208 list_add_tail(&fp->node, &fmb->phys); 209 210 return 0; 211 212 err_regs: 213 kfree(fp); 214 return ret; 215 } 216 EXPORT_SYMBOL_GPL(fixed_phy_add); 217 218 void fixed_phy_del(int phy_addr) 219 { 220 struct fixed_mdio_bus *fmb = &platform_fmb; 221 struct fixed_phy *fp, *tmp; 222 223 list_for_each_entry_safe(fp, tmp, &fmb->phys, node) { 224 if (fp->addr == phy_addr) { 225 list_del(&fp->node); 226 kfree(fp); 227 return; 228 } 229 } 230 } 231 EXPORT_SYMBOL_GPL(fixed_phy_del); 232 233 static int phy_fixed_addr; 234 static DEFINE_SPINLOCK(phy_fixed_addr_lock); 235 236 struct phy_device *fixed_phy_register(unsigned int irq, 237 struct fixed_phy_status *status, 238 struct device_node *np) 239 { 240 struct fixed_mdio_bus *fmb = &platform_fmb; 241 struct phy_device *phy; 242 int phy_addr; 243 int ret; 244 245 /* Get the next available PHY address, up to PHY_MAX_ADDR */ 246 spin_lock(&phy_fixed_addr_lock); 247 if (phy_fixed_addr == PHY_MAX_ADDR) { 248 spin_unlock(&phy_fixed_addr_lock); 249 return ERR_PTR(-ENOSPC); 250 } 251 phy_addr = phy_fixed_addr++; 252 spin_unlock(&phy_fixed_addr_lock); 253 254 ret = fixed_phy_add(PHY_POLL, phy_addr, status); 255 if (ret < 0) 256 return ERR_PTR(ret); 257 258 phy = get_phy_device(fmb->mii_bus, phy_addr, false); 259 if (!phy || IS_ERR(phy)) { 260 fixed_phy_del(phy_addr); 261 return ERR_PTR(-EINVAL); 262 } 263 264 of_node_get(np); 265 phy->dev.of_node = np; 266 267 ret = phy_device_register(phy); 268 if (ret) { 269 phy_device_free(phy); 270 of_node_put(np); 271 fixed_phy_del(phy_addr); 272 return ERR_PTR(ret); 273 } 274 275 return phy; 276 } 277 EXPORT_SYMBOL_GPL(fixed_phy_register); 278 279 static int __init fixed_mdio_bus_init(void) 280 { 281 struct fixed_mdio_bus *fmb = &platform_fmb; 282 int ret; 283 284 pdev = platform_device_register_simple("Fixed MDIO bus", 0, NULL, 0); 285 if (IS_ERR(pdev)) { 286 ret = PTR_ERR(pdev); 287 goto err_pdev; 288 } 289 290 fmb->mii_bus = mdiobus_alloc(); 291 if (fmb->mii_bus == NULL) { 292 ret = -ENOMEM; 293 goto err_mdiobus_reg; 294 } 295 296 snprintf(fmb->mii_bus->id, MII_BUS_ID_SIZE, "fixed-0"); 297 fmb->mii_bus->name = "Fixed MDIO Bus"; 298 fmb->mii_bus->priv = fmb; 299 fmb->mii_bus->parent = &pdev->dev; 300 fmb->mii_bus->read = &fixed_mdio_read; 301 fmb->mii_bus->write = &fixed_mdio_write; 302 fmb->mii_bus->irq = fmb->irqs; 303 304 ret = mdiobus_register(fmb->mii_bus); 305 if (ret) 306 goto err_mdiobus_alloc; 307 308 return 0; 309 310 err_mdiobus_alloc: 311 mdiobus_free(fmb->mii_bus); 312 err_mdiobus_reg: 313 platform_device_unregister(pdev); 314 err_pdev: 315 return ret; 316 } 317 module_init(fixed_mdio_bus_init); 318 319 static void __exit fixed_mdio_bus_exit(void) 320 { 321 struct fixed_mdio_bus *fmb = &platform_fmb; 322 struct fixed_phy *fp, *tmp; 323 324 mdiobus_unregister(fmb->mii_bus); 325 mdiobus_free(fmb->mii_bus); 326 platform_device_unregister(pdev); 327 328 list_for_each_entry_safe(fp, tmp, &fmb->phys, node) { 329 list_del(&fp->node); 330 kfree(fp); 331 } 332 } 333 module_exit(fixed_mdio_bus_exit); 334 335 MODULE_DESCRIPTION("Fixed MDIO bus (MDIO bus emulation with fixed PHYs)"); 336 MODULE_AUTHOR("Vitaly Bordug"); 337 MODULE_LICENSE("GPL"); 338