target/linux/ifxmips/files/drivers/char/ifxmips_eeprom.c

   1 /*
   2  *   This program is free software; you can redistribute it and/or modify
   3  *   it under the terms of the GNU General Public License as published by
   4  *   the Free Software Foundation; either version 2 of the License, or
   5  *   (at your option) any later version.
   6  *
   7  *   This program is distributed in the hope that it will be useful,
   8  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  *   GNU General Public License for more details.
  11  *
  12  *   You should have received a copy of the GNU General Public License
  13  *   along with this program; if not, write to the Free Software
  14  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
  15  *
  16  *   This driver was originally based on the INCA-IP driver, but due to
  17  *   fundamental conceptual drawbacks there has been changed a lot.
  18  *
  19  *   Based on INCA-IP driver Copyright (c) 2003 Gary Jennejohn <gj@denx.de>
  20  *   Based on the VxWorks drivers Copyright (c) 2002, Infineon Technologies.
  21  *
  22  *   Copyright (C) 2006 infineon
  23  *   Copyright (C) 2007 John Crispin <blogic@openwrt.org>
  24  *
  25  */
  26
  27 #define IFAP_EEPROM_DRV_VERSION "0.0.1"
  28
  29 #include <linux/module.h>
  30 #include <linux/errno.h>
  31 #include <linux/signal.h>
  32 #include <linux/sched.h>
  33 #include <linux/timer.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/major.h>
  36 #include <linux/string.h>
  37 #include <linux/fs.h>
  38 #include <linux/fcntl.h>
  39 #include <linux/ptrace.h>
  40 #include <linux/mm.h>
  41 #include <linux/ioport.h>
  42 #include <linux/init.h>
  43 #include <linux/delay.h>
  44 #include <linux/spinlock.h>
  45 #include <linux/slab.h>
  46 #include <asm/system.h>
  47 #include <asm/io.h>
  48 #include <asm/irq.h>
  49 #include <asm/uaccess.h>
  50 #include <asm/bitops.h>
  51
  52 #include <linux/types.h>
  53 #include <linux/kernel.h>
  54 #include <linux/version.h>
  55
  56 #include <asm/ifxmips/ifxmips.h>
  57 #include <asm/ifxmips/ifxmips_irq.h>
  58 #include <asm/ifxmips/ifx_ssc_defines.h>
  59 #include <asm/ifxmips/ifx_ssc.h>
  60
  61 /* allow the user to set the major device number */
  62 static int ifxmips_eeprom_maj = 0;
  63
  64 extern int ifx_ssc_init (void);
  65 extern int ifx_ssc_open (struct inode *inode, struct file *filp);
  66 extern int ifx_ssc_close (struct inode *inode, struct file *filp);
  67 extern void ifx_ssc_cleanup_module (void);
  68 extern int ifx_ssc_ioctl (struct inode *inode, struct file *filp,
  69                           unsigned int cmd, unsigned long data);
  70 extern ssize_t ifx_ssc_kwrite (int port, const char *kbuf, size_t len);
  71 extern ssize_t ifx_ssc_kread (int port, char *kbuf, size_t len);
  72
  73 extern int ifx_ssc_cs_low (unsigned int pin);
  74 extern int ifx_ssc_cs_high (unsigned int pin);
  75 extern int ifx_ssc_txrx (char *tx_buf, unsigned int tx_len, char *rx_buf, unsigned int rx_len);
  76 extern int ifx_ssc_tx (char *tx_buf, unsigned int tx_len);
  77 extern int ifx_ssc_rx (char *rx_buf, unsigned int rx_len);
  78
  79 #define EEPROM_CS IFX_SSC_WHBGPOSTAT_OUT0_POS
  80
  81 /* commands for EEPROM, x25160, x25140 */
  82 #define EEPROM_WREN                     ((unsigned char)0x06)
  83 #define EEPROM_WRDI                     ((unsigned char)0x04)
  84 #define EEPROM_RDSR                     ((unsigned char)0x05)
  85 #define EEPROM_WRSR                     ((unsigned char)0x01)
  86 #define EEPROM_READ                     ((unsigned char)0x03)
  87 #define EEPROM_WRITE                    ((unsigned char)0x02)
  88 #define EEPROM_PAGE_SIZE                4
  89 #define EEPROM_SIZE                     512
  90
  91 static int
  92 eeprom_rdsr (void)
  93 {
  94         int ret = 0;
  95         unsigned char cmd = EEPROM_RDSR;
  96         unsigned long flag;
  97         char status;
  98
  99         local_irq_save(flag);
 100
 101         if ((ret = ifx_ssc_cs_low(EEPROM_CS)) == 0)
 102                 if ((ret = ifx_ssc_txrx(&cmd, 1, &status, 1)) >= 0)
 103                         ret = status & 1;
 104
 105         ifx_ssc_cs_high(EEPROM_CS);
 106         local_irq_restore(flag);
 107
 108         return ret;
 109 }
 110
 111 void
 112 eeprom_wip_over (void)
 113 {
 114         while (eeprom_rdsr())
 115                 printk("waiting for eeprom\n");
 116 }
 117
 118 static int
 119 eeprom_wren (void)
 120 {
 121         unsigned char cmd = EEPROM_WREN;
 122         int ret = 0;
 123         unsigned long flag;
 124
 125         local_irq_save(flag);
 126         if ((ret = ifx_ssc_cs_low(EEPROM_CS)) == 0)
 127                 if ((ret = ifx_ssc_tx(&cmd, 1)) >= 0)
 128                         ret = 0;
 129
 130         ifx_ssc_cs_high(EEPROM_CS);
 131         local_irq_restore(flag);
 132
 133         if (!ret)
 134                 eeprom_wip_over();
 135
 136         return ret;
 137 }
 138
 139 static int
 140 eeprom_wrsr (void)
 141 {
 142         int ret = 0;
 143         unsigned char cmd[2];
 144         unsigned long flag;
 145
 146         cmd[0] = EEPROM_WRSR;
 147         cmd[1] = 0;
 148
 149         if ((ret = eeprom_wren()))
 150         {
 151                 printk ("eeprom_wren fails\n");
 152                 goto out1;
 153         }
 154
 155         local_irq_save(flag);
 156
 157         if ((ret = ifx_ssc_cs_low(EEPROM_CS)))
 158                 goto out;
 159
 160         if ((ret = ifx_ssc_tx(cmd, 2)) < 0) {
 161                 ifx_ssc_cs_high(EEPROM_CS);
 162                 goto out;
 163         }
 164
 165         if ((ret = ifx_ssc_cs_low(EEPROM_CS)))
 166                 goto out;
 167
 168         local_irq_restore(flag);
 169         eeprom_wip_over();
 170
 171         return ret;
 172
 173 out:
 174         local_irq_restore (flag);
 175         eeprom_wip_over ();
 176
 177 out1:
 178         return ret;
 179 }
 180
 181 static int
 182 eeprom_read (unsigned int addr, unsigned char *buf, unsigned int len)
 183 {
 184         int ret = 0;
 185         unsigned char write_buf[2];
 186         unsigned int eff = 0;
 187         unsigned long flag;
 188
 189         while (1)
 190         {
 191                 eeprom_wip_over();
 192                 eff = EEPROM_PAGE_SIZE - (addr % EEPROM_PAGE_SIZE);
 193                 eff = (eff < len) ? eff : len;
 194                 local_irq_save(flag);
 195
 196                 if ((ret = ifx_ssc_cs_low(EEPROM_CS)) < 0)
 197                         goto out;
 198
 199                 write_buf[0] = EEPROM_READ | ((unsigned char) ((addr & 0x100) >> 5));
 200                 write_buf[1] = (addr & 0xff);
 201
 202                 if ((ret = ifx_ssc_txrx (write_buf, 2, buf, eff)) != eff)
 203                 {
 204                         printk("ssc_txrx fails %d\n", ret);
 205                         ifx_ssc_cs_high (EEPROM_CS);
 206                         goto out;
 207                 }
 208
 209                 buf += ret;
 210                 len -= ret;
 211                 addr += ret;
 212
 213                 if ((ret = ifx_ssc_cs_high(EEPROM_CS)))
 214                         goto out;
 215
 216                 local_irq_restore(flag);
 217
 218                 if (len <= 0)
 219                         goto out2;
 220         }
 221
 222 out:
 223         local_irq_restore (flag);
 224 out2:
 225         return ret;
 226 }
 227
 228 static int
 229 eeprom_write (unsigned int addr, unsigned char *buf, unsigned int len)
 230 {
 231         int ret = 0;
 232         unsigned int eff = 0;
 233         unsigned char write_buf[2];
 234         int i;
 235         unsigned char rx_buf[EEPROM_PAGE_SIZE];
 236
 237         while (1)
 238         {
 239                 eeprom_wip_over();
 240
 241                 if ((ret = eeprom_wren()))
 242                 {
 243                         printk("eeprom_wren fails\n");
 244                         goto out;
 245                 }
 246
 247                 write_buf[0] = EEPROM_WRITE | ((unsigned char) ((addr & 0x100) >> 5));
 248                 write_buf[1] = (addr & 0xff);
 249
 250                 eff = EEPROM_PAGE_SIZE - (addr % EEPROM_PAGE_SIZE);
 251                 eff = (eff < len) ? eff : len;
 252
 253                 printk("EEPROM Write:\n");
 254                 for (i = 0; i < eff; i++) {
 255                         printk("%2x ", buf[i]);
 256                         if ((i % 16) == 15)
 257                                 printk("\n");
 258                 }
 259                 printk("\n");
 260
 261                 if ((ret = ifx_ssc_cs_low(EEPROM_CS)))
 262                         goto out;
 263
 264                 if ((ret = ifx_ssc_tx (write_buf, 2)) < 0)
 265                 {
 266                         printk("ssc_tx fails %d\n", ret);
 267                         ifx_ssc_cs_high(EEPROM_CS);
 268                         goto out;
 269                 }
 270
 271                 if ((ret = ifx_ssc_tx (buf, eff)) != eff)
 272                 {
 273                         printk("ssc_tx fails %d\n", ret);
 274                         ifx_ssc_cs_high(EEPROM_CS);
 275                         goto out;
 276                 }
 277
 278                 buf += ret;
 279                 len -= ret;
 280                 addr += ret;
 281
 282                 if ((ret = ifx_ssc_cs_high (EEPROM_CS)))
 283                         goto out;
 284
 285                 printk ("<==");
 286                 eeprom_read((addr - eff), rx_buf, eff);
 287                 for (i = 0; i < eff; i++)
 288                 {
 289                         printk ("[%x]", rx_buf[i]);
 290                 }
 291                 printk ("\n");
 292
 293                 if (len <= 0)
 294                         break;
 295         }
 296
 297 out:
 298         return ret;
 299 }
 300
 301 int
 302 ifxmips_eeprom_open (struct inode *inode, struct file *filp)
 303 {
 304         filp->f_pos = 0;
 305         return 0;
 306 }
 307
 308 int
 309 ifxmips_eeprom_close (struct inode *inode, struct file *filp)
 310 {
 311         return 0;
 312 }
 313
 314 int
 315 ifxmips_eeprom_ioctl (struct inode *inode, struct file *filp, unsigned int cmd, unsigned long data)
 316 {
 317         return 0;
 318 }
 319
 320 ssize_t
 321 ifxmips_eeprom_read (char *buf, size_t len, unsigned int addr)
 322 {
 323         int ret = 0;
 324         unsigned int data;
 325
 326         printk("addr:=%d\n", addr);
 327         printk("len:=%d\n", len);
 328
 329         if ((addr + len) > EEPROM_SIZE)
 330         {
 331                 printk("invalid len\n");
 332                 addr = 0;
 333                 len = EEPROM_SIZE / 2;
 334         }
 335
 336         if ((ret = ifx_ssc_open((struct inode *) 0, NULL)))
 337         {
 338                 printk("ifxmips_eeprom_open fails\n");
 339                 goto out;
 340         }
 341
 342         data = (unsigned int)IFX_SSC_MODE_RXTX;
 343
 344         if ((ret = ifx_ssc_ioctl((struct inode *) 0, NULL, IFX_SSC_RXTX_MODE_SET, (unsigned long) &data)))
 345         {
 346                 printk("set RXTX mode fails\n");
 347                 goto out;
 348         }
 349
 350         if ((ret = eeprom_wrsr()))
 351         {
 352                 printk("EEPROM reset fails\n");
 353                 goto out;
 354         }
 355
 356         if ((ret = eeprom_read(addr, buf, len)))
 357         {
 358                 printk("eeprom read fails\n");
 359                 goto out;
 360         }
 361
 362 out:
 363         if (ifx_ssc_close((struct inode *) 0, NULL))
 364                 printk("ifxmips_eeprom_close fails\n");
 365
 366         return len;
 367 }
 368 EXPORT_SYMBOL(ifxmips_eeprom_read);
 369
 370 static ssize_t
 371 ifxmips_eeprom_fops_read (struct file *filp, char *ubuf, size_t len, loff_t * off)
 372 {
 373         int ret = 0;
 374         unsigned char ssc_rx_buf[EEPROM_SIZE];
 375         long flag;
 376
 377         if (*off >= EEPROM_SIZE)
 378                 return 0;
 379
 380         if (*off + len > EEPROM_SIZE)
 381                 len = EEPROM_SIZE - *off;
 382
 383         if (len == 0)
 384                 return 0;
 385
 386         local_irq_save(flag);
 387
 388         if ((ret = ifxmips_eeprom_read(ssc_rx_buf, len, *off)) < 0)
 389         {
 390                 printk("read fails, err=%x\n", ret);
 391                 local_irq_restore(flag);
 392                 return ret;
 393         }
 394
 395         if (copy_to_user((void*)ubuf, ssc_rx_buf, ret) != 0)
 396         {
 397                 local_irq_restore(flag);
 398                 ret = -EFAULT;
 399         }
 400
 401         local_irq_restore(flag);
 402         *off += len;
 403
 404         return len;
 405 }
 406
 407 ssize_t
 408 ifxmips_eeprom_write (char *buf, size_t len, unsigned int addr)
 409 {
 410         int ret = 0;
 411         unsigned int data;
 412
 413         if ((ret = ifx_ssc_open ((struct inode *) 0, NULL)))
 414         {
 415                 printk ("ifxmips_eeprom_open fails\n");
 416                 goto out;
 417         }
 418
 419         data = (unsigned int) IFX_SSC_MODE_RXTX;
 420
 421         if ((ret = ifx_ssc_ioctl ((struct inode *) 0, NULL, IFX_SSC_RXTX_MODE_SET, (unsigned long) &data)))
 422         {
 423                 printk ("set RXTX mode fails\n");
 424                 goto out;
 425         }
 426
 427         if ((ret = eeprom_wrsr ())) {
 428                 printk ("EEPROM reset fails\n");
 429                 goto out;
 430         }
 431
 432         if ((ret = eeprom_write (addr, buf, len))) {
 433                 printk ("eeprom write fails\n");
 434                 goto out;
 435         }
 436
 437 out:
 438         if (ifx_ssc_close ((struct inode *) 0, NULL))
 439                 printk ("ifxmips_eeprom_close fails\n");
 440
 441         return ret;
 442 }
 443 EXPORT_SYMBOL(ifxmips_eeprom_write);
 444
 445 static ssize_t
 446 ifxmips_eeprom_fops_write (struct file *filp, const char *ubuf, size_t len, loff_t * off)
 447 {
 448         int ret = 0;
 449         unsigned char ssc_tx_buf[EEPROM_SIZE];
 450
 451         if (*off >= EEPROM_SIZE)
 452                 return 0;
 453
 454         if (len + *off > EEPROM_SIZE)
 455                 len = EEPROM_SIZE - *off;
 456
 457         if ((ret = copy_from_user (ssc_tx_buf, ubuf, len)))
 458                 return EFAULT;
 459
 460         ret = ifxmips_eeprom_write (ssc_tx_buf, len, *off);
 461
 462         if (ret > 0)
 463                 *off = ret;
 464
 465         return ret;
 466 }
 467
 468 loff_t
 469 ifxmips_eeprom_llseek (struct file * filp, loff_t off, int whence)
 470 {
 471         loff_t newpos;
 472         switch (whence) {
 473         case SEEK_SET:
 474                 newpos = off;
 475                 break;
 476
 477         case SEEK_CUR:
 478                 newpos = filp->f_pos + off;
 479                 break;
 480
 481         default:
 482                 return -EINVAL;
 483         }
 484
 485         if (newpos < 0)
 486                 return -EINVAL;
 487
 488         filp->f_pos = newpos;
 489
 490         return newpos;
 491 }
 492
 493 static struct file_operations ifxmips_eeprom_fops = {
 494       owner:THIS_MODULE,
 495       llseek:ifxmips_eeprom_llseek,
 496       read:ifxmips_eeprom_fops_read,
 497       write:ifxmips_eeprom_fops_write,
 498       ioctl:ifxmips_eeprom_ioctl,
 499       open:ifxmips_eeprom_open,
 500       release:ifxmips_eeprom_close,
 501 };
 502
 503 int __init
 504 ifxmips_eeprom_init (void)
 505 {
 506         int ret = 0;
 507
 508         ifxmips_eeprom_maj = register_chrdev(0, "eeprom", &ifxmips_eeprom_fops);
 509
 510         if (ifxmips_eeprom_maj < 0)
 511         {
 512                 printk("failed to register eeprom device\n");
 513                 ret = -EINVAL;
 514
 515                 goto out;
 516         }
 517
 518         printk("ifxmips_eeprom : /dev/eeprom mayor %d\n", ifxmips_eeprom_maj);
 519
 520 out:
 521         return ret;
 522 }
 523
 524 void __exit
 525 ifxmips_eeprom_cleanup_module (void)
 526 {
 527         /*if (unregister_chrdev (ifxmips_eeprom_maj, "eeprom")) {
 528                 printk ("Unable to unregister major %d for the EEPROM\n",
 529                         maj);
 530         }*/
 531 }
 532
 533 module_exit (ifxmips_eeprom_cleanup_module);
 534 module_init (ifxmips_eeprom_init);
 535
 536 MODULE_LICENSE ("GPL");
 537 MODULE_AUTHOR ("Peng Liu");
 538 MODULE_DESCRIPTION ("IFAP EEPROM driver");
 539 MODULE_SUPPORTED_DEVICE ("ifxmips_eeprom");
 540
 541