package/system/spi-ks8995/src/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 #include <linux/types.h>
  15 #include <linux/kernel.h>
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18 #include <linux/delay.h>
  19 #include <linux/device.h>
  20
  21 #include <linux/spi/spi.h>
  22
  23 #define DRV_VERSION     "0.1.1"
  24 #define DRV_DESC        "Micrel/Kendin KS8995 Ethernet switch SPI driver"
  25
  26 /*-------------------------------------------------------------------------*/
  27
  28 #define KS8995_REG_ID0          0x00    /* Chip ID0 */
  29 #define KS8995_REG_ID1          0x01    /* Chip ID1 */
  30
  31 #define KS8995_REG_GC0          0x02    /* Global Control 0 */
  32 #define KS8995_REG_GC1          0x03    /* Global Control 1 */
  33 #define KS8995_REG_GC2          0x04    /* Global Control 2 */
  34 #define KS8995_REG_GC3          0x05    /* Global Control 3 */
  35 #define KS8995_REG_GC4          0x06    /* Global Control 4 */
  36 #define KS8995_REG_GC5          0x07    /* Global Control 5 */
  37 #define KS8995_REG_GC6          0x08    /* Global Control 6 */
  38 #define KS8995_REG_GC7          0x09    /* Global Control 7 */
  39 #define KS8995_REG_GC8          0x0a    /* Global Control 8 */
  40 #define KS8995_REG_GC9          0x0b    /* Global Control 9 */
  41
  42 #define KS8995_REG_PC(p,r)      ((0x10 * p) + r)        /* Port Control */
  43 #define KS8995_REG_PS(p,r)      ((0x10 * p) + r + 0xe)  /* Port Status */
  44
  45 #define KS8995_REG_TPC0         0x60    /* TOS Priority Control 0 */
  46 #define KS8995_REG_TPC1         0x61    /* TOS Priority Control 1 */
  47 #define KS8995_REG_TPC2         0x62    /* TOS Priority Control 2 */
  48 #define KS8995_REG_TPC3         0x63    /* TOS Priority Control 3 */
  49 #define KS8995_REG_TPC4         0x64    /* TOS Priority Control 4 */
  50 #define KS8995_REG_TPC5         0x65    /* TOS Priority Control 5 */
  51 #define KS8995_REG_TPC6         0x66    /* TOS Priority Control 6 */
  52 #define KS8995_REG_TPC7         0x67    /* TOS Priority Control 7 */
  53
  54 #define KS8995_REG_MAC0         0x68    /* MAC address 0 */
  55 #define KS8995_REG_MAC1         0x69    /* MAC address 1 */
  56 #define KS8995_REG_MAC2         0x6a    /* MAC address 2 */
  57 #define KS8995_REG_MAC3         0x6b    /* MAC address 3 */
  58 #define KS8995_REG_MAC4         0x6c    /* MAC address 4 */
  59 #define KS8995_REG_MAC5         0x6d    /* MAC address 5 */
  60
  61 #define KS8995_REG_IAC0         0x6e    /* Indirect Access Control 0 */
  62 #define KS8995_REG_IAC1         0x6f    /* Indirect Access Control 0 */
  63
  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 /*-------------------------------------------------------------------------*/
  90
  91 struct ks8995_pdata {
  92         /* not yet implemented */
  93 };
  94
  95 struct ks8995_switch {
  96         struct spi_device       *spi;
  97         struct mutex            lock;
  98         struct ks8995_pdata     *pdata;
  99 };
 100
 101 /*-------------------------------------------------------------------------*/
 102
 103 static inline u8 get_chip_id(u8 val)
 104 {
 105         return ((val >> ID1_CHIPID_S) & ID1_CHIPID_M);
 106 }
 107
 108 static inline u8 get_chip_rev(u8 val)
 109 {
 110         return ((val >> ID1_REVISION_S) & ID1_REVISION_M);
 111 }
 112
 113 /*-------------------------------------------------------------------------*/
 114
 115 static int ks8995_read(struct ks8995_switch *ks, char *buf,
 116                 unsigned offset, size_t count)
 117 {
 118         u8 cmd[2];
 119         struct spi_transfer t[2];
 120         struct spi_message m;
 121         int err;
 122
 123         spi_message_init(&m);
 124
 125         memset(&t, 0, sizeof(t));
 126
 127         t[0].tx_buf = cmd;
 128         t[0].len = sizeof(cmd);
 129         spi_message_add_tail(&t[0], &m);
 130
 131         t[1].rx_buf = buf;
 132         t[1].len = count;
 133         spi_message_add_tail(&t[1], &m);
 134
 135         cmd[0] = KS8995_CMD_READ;
 136         cmd[1] = offset;
 137
 138         mutex_lock(&ks->lock);
 139         err = spi_sync(ks->spi, &m);
 140         mutex_unlock(&ks->lock);
 141
 142         return err ? err : count;
 143 }
 144
 145
 146 static int ks8995_write(struct ks8995_switch *ks, char *buf,
 147                 unsigned offset, size_t count)
 148 {
 149         u8 cmd[2];
 150         struct spi_transfer t[2];
 151         struct spi_message m;
 152         int err;
 153
 154         spi_message_init(&m);
 155
 156         memset(&t, 0, sizeof(t));
 157
 158         t[0].tx_buf = cmd;
 159         t[0].len = sizeof(cmd);
 160         spi_message_add_tail(&t[0], &m);
 161
 162         t[1].tx_buf = buf;
 163         t[1].len = count;
 164         spi_message_add_tail(&t[1], &m);
 165
 166         cmd[0] = KS8995_CMD_WRITE;
 167         cmd[1] = offset;
 168
 169         mutex_lock(&ks->lock);
 170         err = spi_sync(ks->spi, &m);
 171         mutex_unlock(&ks->lock);
 172
 173         return err ? err : count;
 174 }
 175
 176 static inline int ks8995_read_reg(struct ks8995_switch *ks, u8 addr, u8 *buf)
 177 {
 178         return (ks8995_read(ks, buf, addr, 1) != 1);
 179 }
 180
 181 static inline int ks8995_write_reg(struct ks8995_switch *ks, u8 addr, u8 val)
 182 {
 183         char buf = val;
 184
 185         return (ks8995_write(ks, &buf, addr, 1) != 1);
 186 }
 187
 188 /*-------------------------------------------------------------------------*/
 189
 190 #if 0
 191 static int ks8995_setup(struct spi_device *spi)
 192 {
 193         struct ks8995_switch *ks;
 194         u8 t;
 195
 196         ks = dev_get_drvdata(&spi->dev);
 197
 198         ks8995_write_reg(ks, KS8995_REG_GC0, 0x4c);
 199         ks8995_write_reg(ks, KS8995_REG_GC1, 0x05);
 200
 201         ks8995_read_reg(ks, KS8995_REG_GC2, &t);
 202         ks8995_write_reg(ks, KS8995_REG_GC2, t | 1);
 203
 204         ks8995_write_reg(ks, KS8995_REG_GC4, 0x20);
 205
 206         ks8995_write_reg(ks, KS8995_REG_PC(1,0), 0x61);
 207         ks8995_write_reg(ks, KS8995_REG_PC(2,0), 0x61);
 208         ks8995_write_reg(ks, KS8995_REG_PC(3,0), 0x61);
 209         ks8995_write_reg(ks, KS8995_REG_PC(4,0), 0x61);
 210         ks8995_write_reg(ks, KS8995_REG_PC(5,0), 0x61);
 211
 212         ks8995_write_reg(ks, KS8995_REG_PC(5,11), 0x18);
 213
 214         ks8995_write_reg(ks, KS8995_REG_TPC0, 0xff);
 215         ks8995_write_reg(ks, KS8995_REG_TPC1, 0xff);
 216         ks8995_write_reg(ks, KS8995_REG_TPC2, 0xff);
 217         ks8995_write_reg(ks, KS8995_REG_TPC3, 0xff);
 218         ks8995_write_reg(ks, KS8995_REG_TPC4, 0xff);
 219         ks8995_write_reg(ks, KS8995_REG_TPC5, 0xff);
 220         ks8995_write_reg(ks, KS8995_REG_TPC6, 0xff);
 221         ks8995_write_reg(ks, KS8995_REG_TPC7, 0xfe);
 222
 223         return 0;
 224 }
 225 #endif
 226
 227 static int ks8995_stop(struct ks8995_switch *ks)
 228 {
 229         return ks8995_write_reg(ks, KS8995_REG_ID1, 0);
 230 }
 231
 232 static int ks8995_start(struct ks8995_switch *ks)
 233 {
 234         return ks8995_write_reg(ks, KS8995_REG_ID1, 1);
 235 }
 236
 237 static int ks8995_reset(struct ks8995_switch *ks)
 238 {
 239         int err;
 240
 241         err = ks8995_stop(ks);
 242         if (err)
 243                 return err;
 244
 245         udelay(KS8995_RESET_DELAY);
 246
 247         return ks8995_start(ks);
 248 }
 249
 250 /*-------------------------------------------------------------------------*/
 251
 252 static int ks8995_registers_read(struct kobject *kobj,
 253         struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
 254 {
 255         struct device *dev;
 256         struct ks8995_switch *ks8995;
 257
 258         dev = container_of(kobj, struct device, kobj);
 259         ks8995 = dev_get_drvdata(dev);
 260
 261         if (unlikely(off > KS8995_REGS_SIZE))
 262                 return 0;
 263
 264         if ((off + count) > KS8995_REGS_SIZE)
 265                 count = KS8995_REGS_SIZE - off;
 266
 267         if (unlikely(!count))
 268                 return count;
 269
 270         return ks8995_read(ks8995, buf, off, count);
 271 }
 272
 273
 274 static int ks8995_registers_write(struct kobject *kobj,
 275         struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
 276 {
 277         struct device *dev;
 278         struct ks8995_switch *ks8995;
 279
 280         dev = container_of(kobj, struct device, kobj);
 281         ks8995 = dev_get_drvdata(dev);
 282
 283         if (unlikely(off >= KS8995_REGS_SIZE))
 284                 return -EFBIG;
 285
 286         if ((off + count) > KS8995_REGS_SIZE)
 287                 count = KS8995_REGS_SIZE - off;
 288
 289         if (unlikely(!count))
 290                 return count;
 291
 292         return ks8995_write(ks8995, buf, off, count);
 293 }
 294
 295
 296 static struct bin_attribute ks8995_registers_attr = {
 297         .attr = {
 298                 .name   = "registers",
 299                 .mode   = S_IRUSR | S_IWUSR,
 300         },
 301         .size   = KS8995_REGS_SIZE,
 302         .read   = ks8995_registers_read,
 303         .write  = ks8995_registers_write,
 304 };
 305
 306 /*-------------------------------------------------------------------------*/
 307
 308 static int ks8995_probe(struct spi_device *spi)
 309 {
 310         struct ks8995_switch    *ks;
 311         struct ks8995_pdata     *pdata;
 312         u8      ids[2];
 313         int     err;
 314
 315         /* Chip description */
 316         pdata = spi->dev.platform_data;
 317
 318         ks = kzalloc(sizeof(*ks), GFP_KERNEL);
 319         if (!ks) {
 320                 dev_err(&spi->dev, "no memory for private data\n");
 321                 return-ENOMEM;
 322         }
 323
 324         mutex_init(&ks->lock);
 325         ks->pdata = pdata;
 326         ks->spi = spi_dev_get(spi);
 327         dev_set_drvdata(&spi->dev, ks);
 328
 329         spi->mode = SPI_MODE_0;
 330         spi->bits_per_word = 8;
 331         err = spi_setup(spi);
 332         if (err) {
 333                 dev_err(&spi->dev, "spi_setup failed, err=%d \n", err);
 334                 goto err_drvdata;
 335         }
 336
 337         err = ks8995_read(ks, ids, KS8995_REG_ID0, sizeof(ids));
 338         if (err < 0) {
 339                 dev_err(&spi->dev, "unable to read id registers, err=%d \n",
 340                                 err);
 341                 goto err_drvdata;
 342         }
 343
 344         switch (ids[0]) {
 345         case FAMILY_KS8995:
 346                 break;
 347         default:
 348                 dev_err(&spi->dev, "unknown family id:%02x\n", ids[0]);
 349                 err = -ENODEV;
 350                 goto err_drvdata;
 351         }
 352
 353         err = ks8995_reset(ks);
 354         if (err)
 355                 goto err_drvdata;
 356
 357         err = sysfs_create_bin_file(&spi->dev.kobj, &ks8995_registers_attr);
 358         if (err) {
 359                 dev_err(&spi->dev, "unable to create sysfs file, err=%d\n",
 360                                         err);
 361                 goto err_drvdata;
 362         }
 363
 364         dev_info(&spi->dev, "KS89%02X device found, Chip ID:%01x, "
 365                         "Revision:%01x\n", ids[0],
 366                         get_chip_id(ids[1]), get_chip_rev(ids[1]));
 367
 368         return 0;
 369
 370 err_drvdata:
 371         dev_set_drvdata(&spi->dev, NULL);
 372         kfree(ks);
 373         return err;
 374 }
 375
 376 static int ks8995_remove(struct spi_device *spi)
 377 {
 378         struct ks8995_data      *ks8995;
 379
 380         ks8995 = dev_get_drvdata(&spi->dev);
 381         sysfs_remove_bin_file(&spi->dev.kobj, &ks8995_registers_attr);
 382
 383         dev_set_drvdata(&spi->dev, NULL);
 384         kfree(ks8995);
 385
 386         return 0;
 387 }
 388
 389 /*-------------------------------------------------------------------------*/
 390
 391 static struct spi_driver ks8995_driver = {
 392         .driver = {
 393                 .name           = "spi-ks8995",
 394                 .bus            = &spi_bus_type,
 395                 .owner          = THIS_MODULE,
 396         },
 397         .probe          = ks8995_probe,
 398         .remove         = ks8995_remove,
 399 };
 400
 401 static int __init ks8995_init(void)
 402 {
 403         printk(KERN_INFO DRV_DESC " version " DRV_VERSION"\n");
 404
 405         return spi_register_driver(&ks8995_driver);
 406 }
 407 module_init(ks8995_init);
 408
 409 static void __exit ks8995_exit(void)
 410 {
 411         spi_unregister_driver(&ks8995_driver);
 412 }
 413 module_exit(ks8995_exit);
 414
 415 MODULE_DESCRIPTION(DRV_DESC);
 416 MODULE_VERSION(DRV_VERSION);
 417 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 418 MODULE_LICENSE("GPL v2");
 419