board/lwmon5/kbd.c

   1 /*
   2  * (C) Copyright 2007
   3  * Stefan Roese, DENX Software Engineering, sr@denx.de.
   4  *
   5  * (C) Copyright 2001, 2002
   6  * DENX Software Engineering
   7  * Wolfgang Denk, wd@denx.de
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License as
  11  * published by the Free Software Foundation; either version 2 of
  12  * the License, or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  22  * MA 02111-1307 USA
  23  */
  24
  25 /* define DEBUG for debugging output (obviously ;-)) */
  26 #if 0
  27 #define DEBUG
  28 #endif
  29
  30 #include <common.h>
  31 #include <i2c.h>
  32 #include <command.h>
  33 #include <post.h>
  34 #include <serial.h>
  35 #include <malloc.h>
  36
  37 #include <linux/types.h>
  38 #include <linux/string.h>       /* for strdup */
  39
  40 DECLARE_GLOBAL_DATA_PTR;
  41
  42 static void kbd_init (void);
  43 static int compare_magic (uchar *kbd_data, uchar *str);
  44
  45 /*--------------------- Local macros and constants --------------------*/
  46 #define _NOT_USED_      0xFFFFFFFF
  47
  48 /*------------------------- Keyboard controller -----------------------*/
  49 /* command codes */
  50 #define KEYBD_CMD_READ_KEYS     0x01
  51 #define KEYBD_CMD_READ_VERSION  0x02
  52 #define KEYBD_CMD_READ_STATUS   0x03
  53 #define KEYBD_CMD_RESET_ERRORS  0x10
  54
  55 /* status codes */
  56 #define KEYBD_STATUS_MASK       0x3F
  57 #define KEYBD_STATUS_H_RESET    0x20
  58 #define KEYBD_STATUS_BROWNOUT   0x10
  59 #define KEYBD_STATUS_WD_RESET   0x08
  60 #define KEYBD_STATUS_OVERLOAD   0x04
  61 #define KEYBD_STATUS_ILLEGAL_WR 0x02
  62 #define KEYBD_STATUS_ILLEGAL_RD 0x01
  63
  64 /* Number of bytes returned from Keyboard Controller */
  65 #define KEYBD_VERSIONLEN        2       /* version information */
  66
  67 /*
  68  * This is different from the "old" lwmon dsPIC kbd controller
  69  * implementation. Now the controller still answers with 9 bytes,
  70  * but the last 3 bytes are always "0x06 0x07 0x08". So we just
  71  * set the length to compare to 6 instead of 9.
  72  */
  73 #define KEYBD_DATALEN           6       /* normal key scan data */
  74
  75 /* maximum number of "magic" key codes that can be assigned */
  76
  77 static uchar kbd_addr = CFG_I2C_KEYBD_ADDR;
  78
  79 static uchar *key_match (uchar *);
  80
  81 #define KEYBD_SET_DEBUGMODE     '#'     /* Magic key to enable debug output */
  82
  83 /***********************************************************************
  84 F* Function:     int board_postclk_init (void) P*A*Z*
  85  *
  86 P* Parameters:   none
  87 P*
  88 P* Returnvalue:  int
  89 P*                - 0 is always returned.
  90  *
  91 Z* Intention:    This function is the board_postclk_init() method implementation
  92 Z*               for the lwmon board.
  93  *
  94  ***********************************************************************/
  95 int board_postclk_init (void)
  96 {
  97         kbd_init();
  98
  99         return (0);
 100 }
 101
 102 static void kbd_init (void)
 103 {
 104         uchar kbd_data[KEYBD_DATALEN];
 105         uchar tmp_data[KEYBD_DATALEN];
 106         uchar val, errcd;
 107         int i;
 108
 109         i2c_init (CFG_I2C_SPEED, CFG_I2C_SLAVE);
 110
 111         gd->kbd_status = 0;
 112
 113         /* Forced by PIC. Delays <= 175us loose */
 114         udelay(1000);
 115
 116         /* Read initial keyboard error code */
 117         val = KEYBD_CMD_READ_STATUS;
 118         i2c_write (kbd_addr, 0, 0, &val, 1);
 119         i2c_read (kbd_addr, 0, 0, &errcd, 1);
 120         /* clear unused bits */
 121         errcd &= KEYBD_STATUS_MASK;
 122         /* clear "irrelevant" bits. Recommended by Martin Rajek, LWN */
 123         errcd &= ~(KEYBD_STATUS_H_RESET|KEYBD_STATUS_BROWNOUT);
 124         if (errcd) {
 125                 gd->kbd_status |= errcd << 8;
 126         }
 127         /* Reset error code and verify */
 128         val = KEYBD_CMD_RESET_ERRORS;
 129         i2c_write (kbd_addr, 0, 0, &val, 1);
 130         udelay(1000);   /* delay NEEDED by keyboard PIC !!! */
 131
 132         val = KEYBD_CMD_READ_STATUS;
 133         i2c_write (kbd_addr, 0, 0, &val, 1);
 134         i2c_read (kbd_addr, 0, 0, &val, 1);
 135
 136         val &= KEYBD_STATUS_MASK;       /* clear unused bits */
 137         if (val) {                      /* permanent error, report it */
 138                 gd->kbd_status |= val;
 139                 return;
 140         }
 141
 142         /*
 143          * Read current keyboard state.
 144          *
 145          * After the error reset it may take some time before the
 146          * keyboard PIC picks up a valid keyboard scan - the total
 147          * scan time is approx. 1.6 ms (information by Martin Rajek,
 148          * 28 Sep 2002). We read a couple of times for the keyboard
 149          * to stabilize, using a big enough delay.
 150          * 10 times should be enough. If the data is still changing,
 151          * we use what we get :-(
 152          */
 153
 154         memset (tmp_data, 0xFF, KEYBD_DATALEN); /* impossible value */
 155         for (i=0; i<10; ++i) {
 156                 val = KEYBD_CMD_READ_KEYS;
 157                 i2c_write (kbd_addr, 0, 0, &val, 1);
 158                 i2c_read (kbd_addr, 0, 0, kbd_data, KEYBD_DATALEN);
 159
 160                 if (memcmp(kbd_data, tmp_data, KEYBD_DATALEN) == 0) {
 161                         /* consistent state, done */
 162                         break;
 163                 }
 164                 /* remeber last state, delay, and retry */
 165                 memcpy (tmp_data, kbd_data, KEYBD_DATALEN);
 166                 udelay (5000);
 167         }
 168 }
 169
 170 /***********************************************************************
 171 F* Function:     int misc_init_r (void) P*A*Z*
 172  *
 173 P* Parameters:   none
 174 P*
 175 P* Returnvalue:  int
 176 P*                - 0 is always returned, even in the case of a keyboard
 177 P*                    error.
 178  *
 179 Z* Intention:    This function is the misc_init_r() method implementation
 180 Z*               for the lwmon board.
 181 Z*               The keyboard controller is initialized and the result
 182 Z*               of a read copied to the environment variable "keybd".
 183 Z*               If KEYBD_SET_DEBUGMODE is defined, a check is made for
 184 Z*               this key, and if found display to the LCD will be enabled.
 185 Z*               The keys in "keybd" are checked against the magic
 186 Z*               keycommands defined in the environment.
 187 Z*               See also key_match().
 188  *
 189 D* Design:       wd@denx.de
 190 C* Coding:       wd@denx.de
 191 V* Verification: dzu@denx.de
 192  ***********************************************************************/
 193 int misc_init_r_kbd (void)
 194 {
 195         uchar kbd_data[KEYBD_DATALEN];
 196         char keybd_env[2 * KEYBD_DATALEN + 1];
 197         uchar kbd_init_status = gd->kbd_status >> 8;
 198         uchar kbd_status = gd->kbd_status;
 199         uchar val;
 200         char *str;
 201         int i;
 202
 203         if (kbd_init_status) {
 204                 printf ("KEYBD: Error %02X\n", kbd_init_status);
 205         }
 206         if (kbd_status) {               /* permanent error, report it */
 207                 printf ("*** Keyboard error code %02X ***\n", kbd_status);
 208                 sprintf (keybd_env, "%02X", kbd_status);
 209                 setenv ("keybd", keybd_env);
 210                 return 0;
 211         }
 212
 213         /*
 214          * Now we know that we have a working  keyboard,  so  disable
 215          * all output to the LCD except when a key press is detected.
 216          */
 217
 218         if ((console_assign (stdout, "serial") < 0) ||
 219                 (console_assign (stderr, "serial") < 0)) {
 220                 printf ("Can't assign serial port as output device\n");
 221         }
 222
 223         /* Read Version */
 224         val = KEYBD_CMD_READ_VERSION;
 225         i2c_write (kbd_addr, 0, 0, &val, 1);
 226         i2c_read (kbd_addr, 0, 0, kbd_data, KEYBD_VERSIONLEN);
 227         printf ("KEYBD: Version %d.%d\n", kbd_data[0], kbd_data[1]);
 228
 229         /* Read current keyboard state */
 230         val = KEYBD_CMD_READ_KEYS;
 231         i2c_write (kbd_addr, 0, 0, &val, 1);
 232         i2c_read (kbd_addr, 0, 0, kbd_data, KEYBD_DATALEN);
 233
 234         for (i = 0; i < KEYBD_DATALEN; ++i) {
 235                 sprintf (keybd_env + i + i, "%02X", kbd_data[i]);
 236         }
 237         setenv ("keybd", keybd_env);
 238
 239         str = strdup ((char *)key_match (kbd_data));    /* decode keys */
 240 #ifdef KEYBD_SET_DEBUGMODE
 241         if (kbd_data[0] == KEYBD_SET_DEBUGMODE) {       /* set debug mode */
 242                 if ((console_assign (stdout, "lcd") < 0) ||
 243                         (console_assign (stderr, "lcd") < 0)) {
 244                         printf ("Can't assign LCD display as output device\n");
 245                 }
 246         }
 247 #endif /* KEYBD_SET_DEBUGMODE */
 248 #ifdef CONFIG_PREBOOT   /* automatically configure "preboot" command on key match */
 249         setenv ("preboot", str);        /* set or delete definition */
 250 #endif /* CONFIG_PREBOOT */
 251         if (str != NULL) {
 252                 free (str);
 253         }
 254         return (0);
 255 }
 256
 257 #ifdef CONFIG_PREBOOT
 258
 259 static uchar kbd_magic_prefix[] = "key_magic";
 260 static uchar kbd_command_prefix[] = "key_cmd";
 261
 262 static int compare_magic (uchar *kbd_data, uchar *str)
 263 {
 264         uchar compare[KEYBD_DATALEN-1];
 265         char *nxt;
 266         int i;
 267
 268         /* Don't include modifier byte */
 269         memcpy (compare, kbd_data+1, KEYBD_DATALEN-1);
 270
 271         for (; str != NULL; str = (*nxt) ? (uchar *)(nxt+1) : (uchar *)nxt) {
 272                 uchar c;
 273                 int k;
 274
 275                 c = (uchar) simple_strtoul ((char *)str, (char **) (&nxt), 16);
 276
 277                 if (str == (uchar *)nxt) {      /* invalid character */
 278                         break;
 279                 }
 280
 281                 /*
 282                  * Check if this key matches the input.
 283                  * Set matches to zero, so they match only once
 284                  * and we can find duplicates or extra keys
 285                  */
 286                 for (k = 0; k < sizeof(compare); ++k) {
 287                         if (compare[k] == '\0') /* only non-zero entries */
 288                                 continue;
 289                         if (c == compare[k]) {  /* found matching key */
 290                                 compare[k] = '\0';
 291                                 break;
 292                         }
 293                 }
 294                 if (k == sizeof(compare)) {
 295                         return -1;              /* unmatched key */
 296                 }
 297         }
 298
 299         /*
 300          * A full match leaves no keys in the `compare' array,
 301          */
 302         for (i = 0; i < sizeof(compare); ++i) {
 303                 if (compare[i])
 304                 {
 305                         return -1;
 306                 }
 307         }
 308
 309         return 0;
 310 }
 311
 312 /***********************************************************************
 313 F* Function:     static uchar *key_match (uchar *kbd_data) P*A*Z*
 314  *
 315 P* Parameters:   uchar *kbd_data
 316 P*                - The keys to match against our magic definitions
 317 P*
 318 P* Returnvalue:  uchar *
 319 P*                - != NULL: Pointer to the corresponding command(s)
 320 P*                     NULL: No magic is about to happen
 321  *
 322 Z* Intention:    Check if pressed key(s) match magic sequence,
 323 Z*               and return the command string associated with that key(s).
 324 Z*
 325 Z*               If no key press was decoded, NULL is returned.
 326 Z*
 327 Z*               Note: the first character of the argument will be
 328 Z*                     overwritten with the "magic charcter code" of the
 329 Z*                     decoded key(s), or '\0'.
 330 Z*
 331 Z*               Note: the string points to static environment data
 332 Z*                     and must be saved before you call any function that
 333 Z*                     modifies the environment.
 334  *
 335 D* Design:       wd@denx.de
 336 C* Coding:       wd@denx.de
 337 V* Verification: dzu@denx.de
 338  ***********************************************************************/
 339 static uchar *key_match (uchar *kbd_data)
 340 {
 341         char magic[sizeof (kbd_magic_prefix) + 1];
 342         uchar *suffix;
 343         char *kbd_magic_keys;
 344
 345         /*
 346          * The following string defines the characters that can pe appended
 347          * to "key_magic" to form the names of environment variables that
 348          * hold "magic" key codes, i. e. such key codes that can cause
 349          * pre-boot actions. If the string is empty (""), then only
 350          * "key_magic" is checked (old behaviour); the string "125" causes
 351          * checks for "key_magic1", "key_magic2" and "key_magic5", etc.
 352          */
 353         if ((kbd_magic_keys = getenv ("magic_keys")) == NULL)
 354                 kbd_magic_keys = "";
 355
 356         /* loop over all magic keys;
 357          * use '\0' suffix in case of empty string
 358          */
 359         for (suffix=(uchar *)kbd_magic_keys; *suffix || suffix==(uchar *)kbd_magic_keys; ++suffix) {
 360                 sprintf (magic, "%s%c", kbd_magic_prefix, *suffix);
 361                 debug ("### Check magic \"%s\"\n", magic);
 362                 if (compare_magic(kbd_data, (uchar *)getenv(magic)) == 0) {
 363                         char cmd_name[sizeof (kbd_command_prefix) + 1];
 364                         char *cmd;
 365
 366                         sprintf (cmd_name, "%s%c", kbd_command_prefix, *suffix);
 367
 368                         cmd = getenv (cmd_name);
 369                         debug ("### Set PREBOOT to $(%s): \"%s\"\n",
 370                                         cmd_name, cmd ? cmd : "<<NULL>>");
 371                         *kbd_data = *suffix;
 372                         return ((uchar *)cmd);
 373                 }
 374         }
 375         debug ("### Delete PREBOOT\n");
 376         *kbd_data = '\0';
 377         return (NULL);
 378 }
 379 #endif /* CONFIG_PREBOOT */
 380
 381 /***********************************************************************
 382 F* Function:     int do_kbd (cmd_tbl_t *cmdtp, int flag,
 383 F*                           int argc, char *argv[]) P*A*Z*
 384  *
 385 P* Parameters:   cmd_tbl_t *cmdtp
 386 P*                - Pointer to our command table entry
 387 P*               int flag
 388 P*                - If the CMD_FLAG_REPEAT bit is set, then this call is
 389 P*                  a repetition
 390 P*               int argc
 391 P*                - Argument count
 392 P*               char *argv[]
 393 P*                - Array of the actual arguments
 394 P*
 395 P* Returnvalue:  int
 396 P*                - 0 is always returned.
 397  *
 398 Z* Intention:    Implement the "kbd" command.
 399 Z*               The keyboard status is read.  The result is printed on
 400 Z*               the console and written into the "keybd" environment
 401 Z*               variable.
 402  *
 403 D* Design:       wd@denx.de
 404 C* Coding:       wd@denx.de
 405 V* Verification: dzu@denx.de
 406  ***********************************************************************/
 407 int do_kbd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 408 {
 409         uchar kbd_data[KEYBD_DATALEN];
 410         char keybd_env[2 * KEYBD_DATALEN + 1];
 411         uchar val;
 412         int i;
 413
 414 #if 0 /* Done in kbd_init */
 415         i2c_init (CFG_I2C_SPEED, CFG_I2C_SLAVE);
 416 #endif
 417
 418         /* Read keys */
 419         val = KEYBD_CMD_READ_KEYS;
 420         i2c_write (kbd_addr, 0, 0, &val, 1);
 421         i2c_read (kbd_addr, 0, 0, kbd_data, KEYBD_DATALEN);
 422
 423         puts ("Keys:");
 424         for (i = 0; i < KEYBD_DATALEN; ++i) {
 425                 sprintf (keybd_env + i + i, "%02X", kbd_data[i]);
 426                 printf (" %02x", kbd_data[i]);
 427         }
 428         putc ('\n');
 429         setenv ("keybd", keybd_env);
 430         return 0;
 431 }
 432
 433 U_BOOT_CMD(
 434         kbd,    1,      1,      do_kbd,
 435         "kbd     - read keyboard status\n",
 436         NULL
 437 );
 438
 439 /*----------------------------- Utilities -----------------------------*/
 440
 441 #ifdef CONFIG_POST
 442 /*
 443  * Returns 1 if keys pressed to start the power-on long-running tests
 444  * Called from board_init_f().
 445  */
 446 int post_hotkeys_pressed(void)
 447 {
 448         uchar kbd_data[KEYBD_DATALEN];
 449         uchar val;
 450
 451         /* Read keys */
 452         val = KEYBD_CMD_READ_KEYS;
 453         i2c_write (kbd_addr, 0, 0, &val, 1);
 454         i2c_read (kbd_addr, 0, 0, kbd_data, KEYBD_DATALEN);
 455
 456         return (compare_magic(kbd_data, (uchar *)CONFIG_POST_KEY_MAGIC) == 0);
 457 }
 458 #endif