drivers/char/lcd.c

   1 /*
   2  * LCD, LED and Button interface for Cobalt
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file "COPYING" in the main directory of this archive
   6  * for more details.
   7  *
   8  * Copyright (C) 1996, 1997 by Andrew Bose
   9  *
  10  * Linux kernel version history:
  11  *       March 2001: Ported from 2.0.34  by Liam Davies
  12  *
  13  */
  14
  15 #define RTC_IO_EXTENT   0x10    /*Only really two ports, but... */
  16
  17 #include <linux/types.h>
  18 #include <linux/errno.h>
  19 #include <linux/miscdevice.h>
  20 #include <linux/slab.h>
  21 #include <linux/ioport.h>
  22 #include <linux/fcntl.h>
  23 #include <linux/mc146818rtc.h>
  24 #include <linux/netdevice.h>
  25 #include <linux/sched.h>
  26 #include <linux/delay.h>
  27
  28 #include <asm/io.h>
  29 #include <asm/uaccess.h>
  30 #include <asm/system.h>
  31 #include <linux/delay.h>
  32
  33 #include "lcd.h"
  34
  35 static DEFINE_SPINLOCK(lcd_lock);
  36
  37 static int lcd_ioctl(struct inode *inode, struct file *file,
  38                      unsigned int cmd, unsigned long arg);
  39
  40 static unsigned int lcd_present = 1;
  41
  42 /* used in arch/mips/cobalt/reset.c */
  43 int led_state = 0;
  44
  45 #if defined(CONFIG_TULIP) && 0
  46
  47 #define MAX_INTERFACES  8
  48 static linkcheck_func_t linkcheck_callbacks[MAX_INTERFACES];
  49 static void *linkcheck_cookies[MAX_INTERFACES];
  50
  51 int lcd_register_linkcheck_func(int iface_num, void *func, void *cookie)
  52 {
  53         if (iface_num < 0 ||
  54             iface_num >= MAX_INTERFACES ||
  55             linkcheck_callbacks[iface_num] != NULL)
  56                 return -1;
  57         linkcheck_callbacks[iface_num] = (linkcheck_func_t) func;
  58         linkcheck_cookies[iface_num] = cookie;
  59         return 0;
  60 }
  61 #endif
  62
  63 static int lcd_ioctl(struct inode *inode, struct file *file,
  64                      unsigned int cmd, unsigned long arg)
  65 {
  66         struct lcd_display button_display;
  67         unsigned long address, a;
  68
  69         switch (cmd) {
  70         case LCD_On:
  71                 udelay(150);
  72                 BusyCheck();
  73                 LCDWriteInst(0x0F);
  74                 break;
  75
  76         case LCD_Off:
  77                 udelay(150);
  78                 BusyCheck();
  79                 LCDWriteInst(0x08);
  80                 break;
  81
  82         case LCD_Reset:
  83                 udelay(150);
  84                 LCDWriteInst(0x3F);
  85                 udelay(150);
  86                 LCDWriteInst(0x3F);
  87                 udelay(150);
  88                 LCDWriteInst(0x3F);
  89                 udelay(150);
  90                 LCDWriteInst(0x3F);
  91                 udelay(150);
  92                 LCDWriteInst(0x01);
  93                 udelay(150);
  94                 LCDWriteInst(0x06);
  95                 break;
  96
  97         case LCD_Clear:
  98                 udelay(150);
  99                 BusyCheck();
 100                 LCDWriteInst(0x01);
 101                 break;
 102
 103         case LCD_Cursor_Left:
 104                 udelay(150);
 105                 BusyCheck();
 106                 LCDWriteInst(0x10);
 107                 break;
 108
 109         case LCD_Cursor_Right:
 110                 udelay(150);
 111                 BusyCheck();
 112                 LCDWriteInst(0x14);
 113                 break;
 114
 115         case LCD_Cursor_Off:
 116                 udelay(150);
 117                 BusyCheck();
 118                 LCDWriteInst(0x0C);
 119                 break;
 120
 121         case LCD_Cursor_On:
 122                 udelay(150);
 123                 BusyCheck();
 124                 LCDWriteInst(0x0F);
 125                 break;
 126
 127         case LCD_Blink_Off:
 128                 udelay(150);
 129                 BusyCheck();
 130                 LCDWriteInst(0x0E);
 131                 break;
 132
 133         case LCD_Get_Cursor_Pos:{
 134                         struct lcd_display display;
 135
 136                         udelay(150);
 137                         BusyCheck();
 138                         display.cursor_address = (LCDReadInst);
 139                         display.cursor_address =
 140                             (display.cursor_address & 0x07F);
 141                         if (copy_to_user
 142                             ((struct lcd_display *) arg, &display,
 143                              sizeof(struct lcd_display)))
 144                                 return -EFAULT;
 145
 146                         break;
 147                 }
 148
 149
 150         case LCD_Set_Cursor_Pos:{
 151                         struct lcd_display display;
 152
 153                         if (copy_from_user
 154                             (&display, (struct lcd_display *) arg,
 155                              sizeof(struct lcd_display)))
 156                                 return -EFAULT;
 157
 158                         a = (display.cursor_address | kLCD_Addr);
 159
 160                         udelay(150);
 161                         BusyCheck();
 162                         LCDWriteInst(a);
 163
 164                         break;
 165                 }
 166
 167         case LCD_Get_Cursor:{
 168                         struct lcd_display display;
 169
 170                         udelay(150);
 171                         BusyCheck();
 172                         display.character = LCDReadData;
 173
 174                         if (copy_to_user
 175                             ((struct lcd_display *) arg, &display,
 176                              sizeof(struct lcd_display)))
 177                                 return -EFAULT;
 178                         udelay(150);
 179                         BusyCheck();
 180                         LCDWriteInst(0x10);
 181
 182                         break;
 183                 }
 184
 185         case LCD_Set_Cursor:{
 186                         struct lcd_display display;
 187
 188                         if (copy_from_user
 189                             (&display, (struct lcd_display *) arg,
 190                              sizeof(struct lcd_display)))
 191                                 return -EFAULT;
 192
 193                         udelay(150);
 194                         BusyCheck();
 195                         LCDWriteData(display.character);
 196                         udelay(150);
 197                         BusyCheck();
 198                         LCDWriteInst(0x10);
 199
 200                         break;
 201                 }
 202
 203
 204         case LCD_Disp_Left:
 205                 udelay(150);
 206                 BusyCheck();
 207                 LCDWriteInst(0x18);
 208                 break;
 209
 210         case LCD_Disp_Right:
 211                 udelay(150);
 212                 BusyCheck();
 213                 LCDWriteInst(0x1C);
 214                 break;
 215
 216         case LCD_Home:
 217                 udelay(150);
 218                 BusyCheck();
 219                 LCDWriteInst(0x02);
 220                 break;
 221
 222         case LCD_Write:{
 223                         struct lcd_display display;
 224                         unsigned int index;
 225
 226
 227                         if (copy_from_user
 228                             (&display, (struct lcd_display *) arg,
 229                              sizeof(struct lcd_display)))
 230                                 return -EFAULT;
 231
 232                         udelay(150);
 233                         BusyCheck();
 234                         LCDWriteInst(0x80);
 235                         udelay(150);
 236                         BusyCheck();
 237
 238                         for (index = 0; index < (display.size1); index++) {
 239                                 udelay(150);
 240                                 BusyCheck();
 241                                 LCDWriteData(display.line1[index]);
 242                                 BusyCheck();
 243                         }
 244
 245                         udelay(150);
 246                         BusyCheck();
 247                         LCDWriteInst(0xC0);
 248                         udelay(150);
 249                         BusyCheck();
 250                         for (index = 0; index < (display.size2); index++) {
 251                                 udelay(150);
 252                                 BusyCheck();
 253                                 LCDWriteData(display.line2[index]);
 254                         }
 255
 256                         break;
 257                 }
 258
 259         case LCD_Read:{
 260                         struct lcd_display display;
 261
 262                         BusyCheck();
 263                         for (address = kDD_R00; address <= kDD_R01;
 264                              address++) {
 265                                 a = (address | kLCD_Addr);
 266
 267                                 udelay(150);
 268                                 BusyCheck();
 269                                 LCDWriteInst(a);
 270                                 udelay(150);
 271                                 BusyCheck();
 272                                 display.line1[address] = LCDReadData;
 273                         }
 274
 275                         display.line1[0x27] = '\0';
 276
 277                         for (address = kDD_R10; address <= kDD_R11;
 278                              address++) {
 279                                 a = (address | kLCD_Addr);
 280
 281                                 udelay(150);
 282                                 BusyCheck();
 283                                 LCDWriteInst(a);
 284
 285                                 udelay(150);
 286                                 BusyCheck();
 287                                 display.line2[address - 0x40] =
 288                                     LCDReadData;
 289                         }
 290
 291                         display.line2[0x27] = '\0';
 292
 293                         if (copy_to_user
 294                             ((struct lcd_display *) arg, &display,
 295                              sizeof(struct lcd_display)))
 296                                 return -EFAULT;
 297                         break;
 298                 }
 299
 300 //  set all GPIO leds to led_display.leds
 301
 302         case LED_Set:{
 303                         struct lcd_display led_display;
 304
 305
 306                         if (copy_from_user
 307                             (&led_display, (struct lcd_display *) arg,
 308                              sizeof(struct lcd_display)))
 309                                 return -EFAULT;
 310
 311                         led_state = led_display.leds;
 312                         LEDSet(led_state);
 313
 314                         break;
 315                 }
 316
 317
 318 //  set only bit led_display.leds
 319
 320         case LED_Bit_Set:{
 321                         unsigned int i;
 322                         int bit = 1;
 323                         struct lcd_display led_display;
 324
 325
 326                         if (copy_from_user
 327                             (&led_display, (struct lcd_display *) arg,
 328                              sizeof(struct lcd_display)))
 329                                 return -EFAULT;
 330
 331                         for (i = 0; i < (int) led_display.leds; i++) {
 332                                 bit = 2 * bit;
 333                         }
 334
 335                         led_state = led_state | bit;
 336                         LEDSet(led_state);
 337                         break;
 338                 }
 339
 340 //  clear only bit led_display.leds
 341
 342         case LED_Bit_Clear:{
 343                         unsigned int i;
 344                         int bit = 1;
 345                         struct lcd_display led_display;
 346
 347
 348                         if (copy_from_user
 349                             (&led_display, (struct lcd_display *) arg,
 350                              sizeof(struct lcd_display)))
 351                                 return -EFAULT;
 352
 353                         for (i = 0; i < (int) led_display.leds; i++) {
 354                                 bit = 2 * bit;
 355                         }
 356
 357                         led_state = led_state & ~bit;
 358                         LEDSet(led_state);
 359                         break;
 360                 }
 361
 362
 363         case BUTTON_Read:{
 364                         button_display.buttons = GPIRead;
 365                         if (copy_to_user
 366                             ((struct lcd_display *) arg, &button_display,
 367                              sizeof(struct lcd_display)))
 368                                 return -EFAULT;
 369                         break;
 370                 }
 371
 372         case LINK_Check:{
 373                         button_display.buttons =
 374                             *((volatile unsigned long *) (0xB0100060));
 375                         if (copy_to_user
 376                             ((struct lcd_display *) arg, &button_display,
 377                              sizeof(struct lcd_display)))
 378                                 return -EFAULT;
 379                         break;
 380                 }
 381
 382         case LINK_Check_2:{
 383                         int iface_num;
 384
 385                         /* panel-utils should pass in the desired interface status is wanted for
 386                          * in "buttons" of the structure.  We will set this to non-zero if the
 387                          * link is in fact up for the requested interface.  --DaveM
 388                          */
 389                         if (copy_from_user
 390                             (&button_display, (struct lcd_display *) arg,
 391                              sizeof(button_display)))
 392                                 return -EFAULT;
 393                         iface_num = button_display.buttons;
 394 #if defined(CONFIG_TULIP) && 0
 395                         if (iface_num >= 0 &&
 396                             iface_num < MAX_INTERFACES &&
 397                             linkcheck_callbacks[iface_num] != NULL) {
 398                                 button_display.buttons =
 399                                     linkcheck_callbacks[iface_num]
 400                                     (linkcheck_cookies[iface_num]);
 401                         } else
 402 #endif
 403                                 button_display.buttons = 0;
 404
 405                         if (__copy_to_user
 406                             ((struct lcd_display *) arg, &button_display,
 407                              sizeof(struct lcd_display)))
 408                                 return -EFAULT;
 409                         break;
 410                 }
 411
 412         default:
 413                 return -EINVAL;
 414
 415         }
 416
 417         return 0;
 418
 419 }
 420
 421 static int lcd_open(struct inode *inode, struct file *file)
 422 {
 423         if (!lcd_present)
 424                 return -ENXIO;
 425         else
 426                 return 0;
 427 }
 428
 429 /* Only RESET or NEXT counts as button pressed */
 430
 431 static inline int button_pressed(void)
 432 {
 433         unsigned long buttons = GPIRead;
 434
 435         if ((buttons == BUTTON_Next) || (buttons == BUTTON_Next_B)
 436             || (buttons == BUTTON_Reset_B))
 437                 return buttons;
 438         return 0;
 439 }
 440
 441 /* LED daemon sits on this and we wake him up once a key is pressed. */
 442
 443 static int lcd_waiters = 0;
 444
 445 static ssize_t lcd_read(struct file *file, char *buf,
 446                      size_t count, loff_t *ofs)
 447 {
 448         long buttons_now;
 449
 450         if (lcd_waiters > 0)
 451                 return -EINVAL;
 452
 453         lcd_waiters++;
 454         while (((buttons_now = (long) button_pressed()) == 0) &&
 455                !(signal_pending(current))) {
 456                 msleep_interruptible(2000);
 457         }
 458         lcd_waiters--;
 459
 460         if (signal_pending(current))
 461                 return -ERESTARTSYS;
 462         return buttons_now;
 463 }
 464
 465 /*
 466  *      The various file operations we support.
 467  */
 468
 469 static const struct file_operations lcd_fops = {
 470         .read = lcd_read,
 471         .ioctl = lcd_ioctl,
 472         .open = lcd_open,
 473 };
 474
 475 static struct miscdevice lcd_dev = {
 476         MISC_DYNAMIC_MINOR,
 477         "lcd",
 478         &lcd_fops
 479 };
 480
 481 static int lcd_init(void)
 482 {
 483         int ret;
 484         unsigned long data;
 485
 486         pr_info("%s\n", LCD_DRIVER);
 487         ret = misc_register(&lcd_dev);
 488         if (ret) {
 489                 printk(KERN_WARNING LCD "Unable to register misc device.\n");
 490                 return ret;
 491         }
 492
 493         /* Check region? Naaah! Just snarf it up. */
 494 /*      request_region(RTC_PORT(0), RTC_IO_EXTENT, "lcd");*/
 495
 496         udelay(150);
 497         data = LCDReadData;
 498         if ((data & 0x000000FF) == (0x00)) {
 499                 lcd_present = 0;
 500                 pr_info(LCD "LCD Not Present\n");
 501         } else {
 502                 lcd_present = 1;
 503                 WRITE_GAL(kGal_DevBank2PReg, kGal_DevBank2Cfg);
 504                 WRITE_GAL(kGal_DevBank3PReg, kGal_DevBank3Cfg);
 505         }
 506
 507         return 0;
 508 }
 509
 510 static void __exit lcd_exit(void)
 511 {
 512         misc_deregister(&lcd_dev);
 513 }
 514
 515 module_init(lcd_init);
 516 module_exit(lcd_exit);
 517
 518 MODULE_AUTHOR("Andrew Bose");
 519 MODULE_LICENSE("GPL");