drivers/net/phy/spi_ks8995.c

   1 /*
   2  * SPI driver for Micrel/Kendin KS8995M ethernet switch
   3  *
   4  * Copyright (C) 2008 Gabor Juhos <juhosg at openwrt.org>
   5  *
   6  * This file was based on: drivers/spi/at25.c
   7  *     Copyright (C) 2006 David Brownell
   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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/types.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/delay.h>
  20 #include <linux/device.h>
  21
  22 #include <linux/spi/spi.h>
  23
  24 #define DRV_VERSION             "0.1.1"
  25 #define DRV_DESC                "Micrel KS8995 Ethernet switch SPI driver"
  26
  27 /* ------------------------------------------------------------------------ */
  28
  29 #define KS8995_REG_ID0          0x00    /* Chip ID0 */
  30 #define KS8995_REG_ID1          0x01    /* Chip ID1 */
  31
  32 #define KS8995_REG_GC0          0x02    /* Global Control 0 */
  33 #define KS8995_REG_GC1          0x03    /* Global Control 1 */
  34 #define KS8995_REG_GC2          0x04    /* Global Control 2 */
  35 #define KS8995_REG_GC3          0x05    /* Global Control 3 */
  36 #define KS8995_REG_GC4          0x06    /* Global Control 4 */
  37 #define KS8995_REG_GC5          0x07    /* Global Control 5 */
  38 #define KS8995_REG_GC6          0x08    /* Global Control 6 */
  39 #define KS8995_REG_GC7          0x09    /* Global Control 7 */
  40 #define KS8995_REG_GC8          0x0a    /* Global Control 8 */
  41 #define KS8995_REG_GC9          0x0b    /* Global Control 9 */
  42
  43 #define KS8995_REG_PC(p, r)     ((0x10 * p) + r)         /* Port Control */
  44 #define KS8995_REG_PS(p, r)     ((0x10 * p) + r + 0xe)  /* Port Status */
  45
  46 #define KS8995_REG_TPC0         0x60    /* TOS Priority Control 0 */
  47 #define KS8995_REG_TPC1         0x61    /* TOS Priority Control 1 */
  48 #define KS8995_REG_TPC2         0x62    /* TOS Priority Control 2 */
  49 #define KS8995_REG_TPC3         0x63    /* TOS Priority Control 3 */
  50 #define KS8995_REG_TPC4         0x64    /* TOS Priority Control 4 */
  51 #define KS8995_REG_TPC5         0x65    /* TOS Priority Control 5 */
  52 #define KS8995_REG_TPC6         0x66    /* TOS Priority Control 6 */
  53 #define KS8995_REG_TPC7         0x67    /* TOS Priority Control 7 */
  54
  55 #define KS8995_REG_MAC0         0x68    /* MAC address 0 */
  56 #define KS8995_REG_MAC1         0x69    /* MAC address 1 */
  57 #define KS8995_REG_MAC2         0x6a    /* MAC address 2 */
  58 #define KS8995_REG_MAC3         0x6b    /* MAC address 3 */
  59 #define KS8995_REG_MAC4         0x6c    /* MAC address 4 */
  60 #define KS8995_REG_MAC5         0x6d    /* MAC address 5 */
  61
  62 #define KS8995_REG_IAC0         0x6e    /* Indirect Access Control 0 */
  63 #define KS8995_REG_IAC1         0x6f    /* Indirect Access Control 0 */
  64 #define KS8995_REG_IAD7         0x70    /* Indirect Access Data 7 */
  65 #define KS8995_REG_IAD6         0x71    /* Indirect Access Data 6 */
  66 #define KS8995_REG_IAD5         0x72    /* Indirect Access Data 5 */
  67 #define KS8995_REG_IAD4         0x73    /* Indirect Access Data 4 */
  68 #define KS8995_REG_IAD3         0x74    /* Indirect Access Data 3 */
  69 #define KS8995_REG_IAD2         0x75    /* Indirect Access Data 2 */
  70 #define KS8995_REG_IAD1         0x76    /* Indirect Access Data 1 */
  71 #define KS8995_REG_IAD0         0x77    /* Indirect Access Data 0 */
  72
  73 #define KS8995_REGS_SIZE        0x80
  74
  75 #define ID1_CHIPID_M            0xf
  76 #define ID1_CHIPID_S            4
  77 #define ID1_REVISION_M          0x7
  78 #define ID1_REVISION_S          1
  79 #define ID1_START_SW            1       /* start the switch */
  80
  81 #define FAMILY_KS8995           0x95
  82 #define CHIPID_M                0
  83
  84 #define KS8995_CMD_WRITE        0x02U
  85 #define KS8995_CMD_READ         0x03U
  86
  87 #define KS8995_RESET_DELAY      10 /* usec */
  88
  89 struct ks8995_pdata {
  90         /* not yet implemented */
  91 };
  92
  93 struct ks8995_switch {
  94         struct spi_device       *spi;
  95         struct mutex            lock;
  96         struct ks8995_pdata     *pdata;
  97 };
  98
  99 static inline u8 get_chip_id(u8 val)
 100 {
 101         return (val >> ID1_CHIPID_S) & ID1_CHIPID_M;
 102 }
 103
 104 static inline u8 get_chip_rev(u8 val)
 105 {
 106         return (val >> ID1_REVISION_S) & ID1_REVISION_M;
 107 }
 108
 109 /* ------------------------------------------------------------------------ */
 110 static int ks8995_read(struct ks8995_switch *ks, char *buf,
 111                  unsigned offset, size_t count)
 112 {
 113         u8 cmd[2];
 114         struct spi_transfer t[2];
 115         struct spi_message m;
 116         int err;
 117
 118         spi_message_init(&m);
 119
 120         memset(&t, 0, sizeof(t));
 121
 122         t[0].tx_buf = cmd;
 123         t[0].len = sizeof(cmd);
 124         spi_message_add_tail(&t[0], &m);
 125
 126         t[1].rx_buf = buf;
 127         t[1].len = count;
 128         spi_message_add_tail(&t[1], &m);
 129
 130         cmd[0] = KS8995_CMD_READ;
 131         cmd[1] = offset;
 132
 133         mutex_lock(&ks->lock);
 134         err = spi_sync(ks->spi, &m);
 135         mutex_unlock(&ks->lock);
 136
 137         return err ? err : count;
 138 }
 139
 140
 141 static int ks8995_write(struct ks8995_switch *ks, char *buf,
 142                  unsigned offset, size_t count)
 143 {
 144         u8 cmd[2];
 145         struct spi_transfer t[2];
 146         struct spi_message m;
 147         int err;
 148
 149         spi_message_init(&m);
 150
 151         memset(&t, 0, sizeof(t));
 152
 153         t[0].tx_buf = cmd;
 154         t[0].len = sizeof(cmd);
 155         spi_message_add_tail(&t[0], &m);
 156
 157         t[1].tx_buf = buf;
 158         t[1].len = count;
 159         spi_message_add_tail(&t[1], &m);
 160
 161         cmd[0] = KS8995_CMD_WRITE;
 162         cmd[1] = offset;
 163
 164         mutex_lock(&ks->lock);
 165         err = spi_sync(ks->spi, &m);
 166         mutex_unlock(&ks->lock);
 167
 168         return err ? err : count;
 169 }
 170
 171 static inline int ks8995_read_reg(struct ks8995_switch *ks, u8 addr, u8 *buf)
 172 {
 173         return ks8995_read(ks, buf, addr, 1) != 1;
 174 }
 175
 176 static inline int ks8995_write_reg(struct ks8995_switch *ks, u8 addr, u8 val)
 177 {
 178         char buf = val;
 179
 180         return ks8995_write(ks, &buf, addr, 1) != 1;
 181 }
 182
 183 /* ------------------------------------------------------------------------ */
 184
 185 static int ks8995_stop(struct ks8995_switch *ks)
 186 {
 187         return ks8995_write_reg(ks, KS8995_REG_ID1, 0);
 188 }
 189
 190 static int ks8995_start(struct ks8995_switch *ks)
 191 {
 192         return ks8995_write_reg(ks, KS8995_REG_ID1, 1);
 193 }
 194
 195 static int ks8995_reset(struct ks8995_switch *ks)
 196 {
 197         int err;
 198
 199         err = ks8995_stop(ks);
 200         if (err)
 201                 return err;
 202
 203         udelay(KS8995_RESET_DELAY);
 204
 205         return ks8995_start(ks);
 206 }
 207
 208 /* ------------------------------------------------------------------------ */
 209
 210 static ssize_t ks8995_registers_read(struct file *filp, struct kobject *kobj,
 211         struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
 212 {
 213         struct device *dev;
 214         struct ks8995_switch *ks8995;
 215
 216         dev = container_of(kobj, struct device, kobj);
 217         ks8995 = dev_get_drvdata(dev);
 218
 219         if (unlikely(off > KS8995_REGS_SIZE))
 220                 return 0;
 221
 222         if ((off + count) > KS8995_REGS_SIZE)
 223                 count = KS8995_REGS_SIZE - off;
 224
 225         if (unlikely(!count))
 226                 return count;
 227
 228         return ks8995_read(ks8995, buf, off, count);
 229 }
 230
 231
 232 static ssize_t ks8995_registers_write(struct file *filp, struct kobject *kobj,
 233         struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
 234 {
 235         struct device *dev;
 236         struct ks8995_switch *ks8995;
 237
 238         dev = container_of(kobj, struct device, kobj);
 239         ks8995 = dev_get_drvdata(dev);
 240
 241         if (unlikely(off >= KS8995_REGS_SIZE))
 242                 return -EFBIG;
 243
 244         if ((off + count) > KS8995_REGS_SIZE)
 245                 count = KS8995_REGS_SIZE - off;
 246
 247         if (unlikely(!count))
 248                 return count;
 249
 250         return ks8995_write(ks8995, buf, off, count);
 251 }
 252
 253
 254 static struct bin_attribute ks8995_registers_attr = {
 255         .attr = {
 256                 .name   = "registers",
 257                 .mode   = S_IRUSR | S_IWUSR,
 258         },
 259         .size   = KS8995_REGS_SIZE,
 260         .read   = ks8995_registers_read,
 261         .write  = ks8995_registers_write,
 262 };
 263
 264 /* ------------------------------------------------------------------------ */
 265
 266 static int ks8995_probe(struct spi_device *spi)
 267 {
 268         struct ks8995_switch    *ks;
 269         struct ks8995_pdata     *pdata;
 270         u8      ids[2];
 271         int     err;
 272
 273         /* Chip description */
 274         pdata = spi->dev.platform_data;
 275
 276         ks = kzalloc(sizeof(*ks), GFP_KERNEL);
 277         if (!ks)
 278                 return -ENOMEM;
 279
 280         mutex_init(&ks->lock);
 281         ks->pdata = pdata;
 282         ks->spi = spi_dev_get(spi);
 283         spi_set_drvdata(spi, ks);
 284
 285         spi->mode = SPI_MODE_0;
 286         spi->bits_per_word = 8;
 287         err = spi_setup(spi);
 288         if (err) {
 289                 dev_err(&spi->dev, "spi_setup failed, err=%d\n", err);
 290                 goto err_drvdata;
 291         }
 292
 293         err = ks8995_read(ks, ids, KS8995_REG_ID0, sizeof(ids));
 294         if (err < 0) {
 295                 dev_err(&spi->dev, "unable to read id registers, err=%d\n",
 296                                 err);
 297                 goto err_drvdata;
 298         }
 299
 300         switch (ids[0]) {
 301         case FAMILY_KS8995:
 302                 break;
 303         default:
 304                 dev_err(&spi->dev, "unknown family id:%02x\n", ids[0]);
 305                 err = -ENODEV;
 306                 goto err_drvdata;
 307         }
 308
 309         err = ks8995_reset(ks);
 310         if (err)
 311                 goto err_drvdata;
 312
 313         err = sysfs_create_bin_file(&spi->dev.kobj, &ks8995_registers_attr);
 314         if (err) {
 315                 dev_err(&spi->dev, "unable to create sysfs file, err=%d\n",
 316                                     err);
 317                 goto err_drvdata;
 318         }
 319
 320         dev_info(&spi->dev, "KS89%02X device found, Chip ID:%01x, "
 321                         "Revision:%01x\n", ids[0],
 322                         get_chip_id(ids[1]), get_chip_rev(ids[1]));
 323
 324         return 0;
 325
 326 err_drvdata:
 327         kfree(ks);
 328         return err;
 329 }
 330
 331 static int ks8995_remove(struct spi_device *spi)
 332 {
 333         struct ks8995_data      *ks8995;
 334
 335         ks8995 = spi_get_drvdata(spi);
 336         sysfs_remove_bin_file(&spi->dev.kobj, &ks8995_registers_attr);
 337
 338         kfree(ks8995);
 339
 340         return 0;
 341 }
 342
 343 /* ------------------------------------------------------------------------ */
 344
 345 static struct spi_driver ks8995_driver = {
 346         .driver = {
 347                 .name       = "spi-ks8995",
 348                 .owner     = THIS_MODULE,
 349         },
 350         .probe    = ks8995_probe,
 351         .remove   = ks8995_remove,
 352 };
 353
 354 module_spi_driver(ks8995_driver);
 355
 356 MODULE_DESCRIPTION(DRV_DESC);
 357 MODULE_VERSION(DRV_VERSION);
 358 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 359 MODULE_LICENSE("GPL v2");