target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_mdio.c

   1 /*
   2  *  Atheros AR71xx built-in ethernet mac driver
   3  *
   4  *  Copyright (C) 2008 Gabor Juhos <juhosg@openwrt.org>
   5  *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
   6  *
   7  *  Based on Atheros' AG7100 driver
   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 version 2 as published
  11  *  by the Free Software Foundation.
  12  */
  13
  14 #include "ag71xx.h"
  15
  16 #define AG71XX_MDIO_RETRY       1000
  17 #define AG71XX_MDIO_DELAY       5
  18
  19 struct ag71xx_mdio *ag71xx_mdio_bus;
  20
  21 static inline void ag71xx_mdio_wr(struct ag71xx_mdio *am, unsigned reg,
  22                                   u32 value)
  23 {
  24         __raw_writel(value, am->mdio_base + reg - AG71XX_REG_MII_CFG);
  25 }
  26
  27 static inline u32 ag71xx_mdio_rr(struct ag71xx_mdio *am, unsigned reg)
  28 {
  29         return __raw_readl(am->mdio_base + reg - AG71XX_REG_MII_CFG);
  30 }
  31
  32 static void ag71xx_mdio_dump_regs(struct ag71xx_mdio *am)
  33 {
  34         DBG("%s: mii_cfg=%08x, mii_cmd=%08x, mii_addr=%08x\n",
  35                 am->mii_bus.name,
  36                 ag71xx_mdio_rr(am, AG71XX_REG_MII_CFG),
  37                 ag71xx_mdio_rr(am, AG71XX_REG_MII_CMD),
  38                 ag71xx_mdio_rr(am, AG71XX_REG_MII_ADDR));
  39         DBG("%s: mii_ctrl=%08x, mii_status=%08x, mii_ind=%08x\n",
  40                 am->mii_bus.name,
  41                 ag71xx_mdio_rr(am, AG71XX_REG_MII_CTRL),
  42                 ag71xx_mdio_rr(am, AG71XX_REG_MII_STATUS),
  43                 ag71xx_mdio_rr(am, AG71XX_REG_MII_IND));
  44 }
  45
  46 static int ag71xx_mdio_mii_read(struct ag71xx_mdio *am, int addr, int reg)
  47 {
  48         int ret;
  49         int i;
  50
  51         ag71xx_mdio_wr(am, AG71XX_REG_MII_CMD, MII_CMD_WRITE);
  52         ag71xx_mdio_wr(am, AG71XX_REG_MII_ADDR,
  53                         ((addr & 0xff) << MII_ADDR_SHIFT) | (reg & 0xff));
  54         ag71xx_mdio_wr(am, AG71XX_REG_MII_CMD, MII_CMD_READ);
  55
  56         i = AG71XX_MDIO_RETRY;
  57         while (ag71xx_mdio_rr(am, AG71XX_REG_MII_IND) & MII_IND_BUSY) {
  58                 if (i-- == 0) {
  59                         printk(KERN_ERR "%s: mii_read timed out\n",
  60                                 am->mii_bus.name);
  61                         ret = 0xffff;
  62                         goto out;
  63                 }
  64                 udelay(AG71XX_MDIO_DELAY);
  65         }
  66
  67         ret = ag71xx_mdio_rr(am, AG71XX_REG_MII_STATUS) & 0xffff;
  68         ag71xx_mdio_wr(am, AG71XX_REG_MII_CMD, MII_CMD_WRITE);
  69
  70         DBG("mii_read: addr=%04x, reg=%04x, value=%04x\n", addr, reg, ret);
  71
  72  out:
  73         return ret;
  74 }
  75
  76 static void ag71xx_mdio_mii_write(struct ag71xx_mdio *am,
  77                                   int addr, int reg, u16 val)
  78 {
  79         int i;
  80
  81         DBG("mii_write: addr=%04x, reg=%04x, value=%04x\n", addr, reg, val);
  82
  83         ag71xx_mdio_wr(am, AG71XX_REG_MII_ADDR,
  84                         ((addr & 0xff) << MII_ADDR_SHIFT) | (reg & 0xff));
  85         ag71xx_mdio_wr(am, AG71XX_REG_MII_CTRL, val);
  86
  87         i = AG71XX_MDIO_RETRY;
  88         while (ag71xx_mdio_rr(am, AG71XX_REG_MII_IND) & MII_IND_BUSY) {
  89                 if (i-- == 0) {
  90                         printk(KERN_ERR "%s: mii_write timed out\n",
  91                                 am->mii_bus.name);
  92                         break;
  93                 }
  94                 udelay(AG71XX_MDIO_DELAY);
  95         }
  96 }
  97
  98 static int ag71xx_mdio_reset(struct mii_bus *bus)
  99 {
 100         struct ag71xx_mdio *am = bus->priv;
 101
 102         ag71xx_mdio_wr(am, AG71XX_REG_MII_CFG, MII_CFG_RESET);
 103         udelay(100);
 104
 105         ag71xx_mdio_wr(am, AG71XX_REG_MII_CFG, MII_CFG_CLK_DIV_28);
 106         udelay(100);
 107
 108         return 0;
 109 }
 110
 111 static int ag71xx_mdio_read(struct mii_bus *bus, int addr, int reg)
 112 {
 113         struct ag71xx_mdio *am = bus->priv;
 114
 115         return ag71xx_mdio_mii_read(am, addr, reg);
 116 }
 117
 118 static int ag71xx_mdio_write(struct mii_bus *bus, int addr, int reg, u16 val)
 119 {
 120         struct ag71xx_mdio *am = bus->priv;
 121
 122         ag71xx_mdio_mii_write(am, addr, reg, val);
 123         return 0;
 124 }
 125
 126 static int __init ag71xx_mdio_probe(struct platform_device *pdev)
 127 {
 128         struct ag71xx_mdio_platform_data *pdata;
 129         struct ag71xx_mdio *am;
 130         struct resource *res;
 131         int i;
 132         int err;
 133
 134         if (ag71xx_mdio_bus)
 135                 return -EBUSY;
 136
 137         am = kzalloc(sizeof(*am), GFP_KERNEL);
 138         if (!am) {
 139                 err = -ENOMEM;
 140                 goto err_out;
 141         }
 142
 143         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 144         if (!res) {
 145                 dev_err(&pdev->dev, "no iomem resource found\n");
 146                 err = -ENXIO;
 147                 goto err_out;
 148         }
 149
 150         am->mdio_base = ioremap_nocache(res->start, res->end - res->start + 1);
 151         if (!am->mdio_base) {
 152                 dev_err(&pdev->dev, "unable to ioremap registers\n");
 153                 err = -ENOMEM;
 154                 goto err_free_mdio;
 155         }
 156
 157         am->mii_bus.name = "ag71xx_mdio";
 158         am->mii_bus.read = ag71xx_mdio_read;
 159         am->mii_bus.write = ag71xx_mdio_write;
 160         am->mii_bus.reset = ag71xx_mdio_reset;
 161         am->mii_bus.irq = am->mii_irq;
 162         am->mii_bus.priv = am;
 163         am->mii_bus.dev = &pdev->dev;
 164         snprintf(am->mii_bus.id, MII_BUS_ID_SIZE, "%x", 0);
 165
 166         pdata = pdev->dev.platform_data;
 167         if (pdata)
 168                 am->mii_bus.phy_mask = pdata->phy_mask;
 169
 170         for (i = 0; i < PHY_MAX_ADDR; i++)
 171                 am->mii_irq[i] = PHY_POLL;
 172
 173         err = mdiobus_register(&am->mii_bus);
 174         if (err)
 175                 goto err_iounmap;
 176
 177         ag71xx_mdio_dump_regs(am);
 178
 179         platform_set_drvdata(pdev, am);
 180         ag71xx_mdio_bus = am;
 181         return 0;
 182
 183  err_iounmap:
 184         iounmap(am->mdio_base);
 185  err_free_mdio:
 186         kfree(am);
 187  err_out:
 188         return err;
 189 }
 190
 191 static int __exit ag71xx_mdio_remove(struct platform_device *pdev)
 192 {
 193         struct ag71xx_mdio *am = platform_get_drvdata(pdev);
 194
 195         if (am) {
 196                 ag71xx_mdio_bus = NULL;
 197                 mdiobus_unregister(&am->mii_bus);
 198                 iounmap(am->mdio_base);
 199                 kfree(am);
 200                 platform_set_drvdata(pdev, NULL);
 201         }
 202
 203         return 0;
 204 }
 205
 206 static struct platform_driver ag71xx_mdio_driver = {
 207         .probe          = ag71xx_mdio_probe,
 208         .remove         = __exit_p(ag71xx_mdio_remove),
 209         .driver = {
 210                 .name   = "ag71xx-mdio",
 211         }
 212 };
 213
 214 int ag71xx_mdio_driver_init(void)
 215 {
 216         return platform_driver_register(&ag71xx_mdio_driver);
 217 }
 218
 219 void ag71xx_mdio_driver_exit(void)
 220 {
 221         platform_driver_unregister(&ag71xx_mdio_driver);
 222 }