drivers/parisc/led.c

   1 /*
   2  *    Chassis LCD/LED driver for HP-PARISC workstations
   3  *
   4  *      (c) Copyright 2000 Red Hat Software
   5  *      (c) Copyright 2000 Helge Deller <hdeller@redhat.com>
   6  *      (c) Copyright 2001-2004 Helge Deller <deller@gmx.de>
   7  *      (c) Copyright 2001 Randolph Chung <tausq@debian.org>
   8  *
   9  *      This program is free software; you can redistribute it and/or modify
  10  *      it under the terms of the GNU General Public License as published by
  11  *      the Free Software Foundation; either version 2 of the License, or
  12  *      (at your option) any later version.
  13  *
  14  * TODO:
  15  *      - speed-up calculations with inlined assembler
  16  *      - interface to write to second row of LCD from /proc (if technically possible)
  17  *
  18  * Changes:
  19  *      - Audit copy_from_user in led_proc_write.
  20  *                                Daniele Bellucci <bellucda@tiscali.it>
  21  */
  22
  23 #include <linux/config.h>
  24 #include <linux/module.h>
  25 #include <linux/stddef.h>       /* for offsetof() */
  26 #include <linux/init.h>
  27 #include <linux/types.h>
  28 #include <linux/ioport.h>
  29 #include <linux/utsname.h>
  30 #include <linux/delay.h>
  31 #include <linux/netdevice.h>
  32 #include <linux/inetdevice.h>
  33 #include <linux/in.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/kernel_stat.h>
  36 #include <linux/reboot.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/ctype.h>
  39 #include <linux/blkdev.h>
  40 #include <asm/io.h>
  41 #include <asm/processor.h>
  42 #include <asm/hardware.h>
  43 #include <asm/param.h>          /* HZ */
  44 #include <asm/led.h>
  45 #include <asm/pdc.h>
  46 #include <asm/uaccess.h>
  47
  48 /* The control of the LEDs and LCDs on PARISC-machines have to be done
  49    completely in software. The necessary calculations are done in a tasklet
  50    which is scheduled at every timer interrupt and since the calculations
  51    may consume relatively much CPU-time some of the calculations can be
  52    turned off with the following variables (controlled via procfs) */
  53
  54 static int led_type = -1;
  55 static int led_heartbeat = 1;
  56 static int led_diskio = 1;
  57 static int led_lanrxtx = 1;
  58 static char lcd_text[32];
  59 static char lcd_text_default[32];
  60
  61 #if 0
  62 #define DPRINTK(x)      printk x
  63 #else
  64 #define DPRINTK(x)
  65 #endif
  66
  67
  68 struct lcd_block {
  69         unsigned char command;  /* stores the command byte      */
  70         unsigned char on;       /* value for turning LED on     */
  71         unsigned char off;      /* value for turning LED off    */
  72 };
  73
  74 /* Structure returned by PDC_RETURN_CHASSIS_INFO */
  75 /* NOTE: we use unsigned long:16 two times, since the following member
  76    lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */
  77 struct pdc_chassis_lcd_info_ret_block {
  78         unsigned long model:16;         /* DISPLAY_MODEL_XXXX */
  79         unsigned long lcd_width:16;     /* width of the LCD in chars (DISPLAY_MODEL_LCD only) */
  80         unsigned long lcd_cmd_reg_addr; /* ptr to LCD cmd-register & data ptr for LED */
  81         unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */
  82         unsigned int min_cmd_delay;     /* delay in uS after cmd-write (LCD only) */
  83         unsigned char reset_cmd1;       /* command #1 for writing LCD string (LCD only) */
  84         unsigned char reset_cmd2;       /* command #2 for writing LCD string (LCD only) */
  85         unsigned char act_enable;       /* 0 = no activity (LCD only) */
  86         struct lcd_block heartbeat;
  87         struct lcd_block disk_io;
  88         struct lcd_block lan_rcv;
  89         struct lcd_block lan_tx;
  90         char _pad;
  91 };
  92
  93
  94 /* LCD_CMD and LCD_DATA for KittyHawk machines */
  95 #define KITTYHAWK_LCD_CMD  F_EXTEND(0xf0190000UL) /* 64bit-ready */
  96 #define KITTYHAWK_LCD_DATA (KITTYHAWK_LCD_CMD+1)
  97
  98 /* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's
  99  * HP seems to have used Sharp/Hitachi HD44780 LCDs most of the time. */
 100 static struct pdc_chassis_lcd_info_ret_block
 101 lcd_info __attribute__((aligned(8))) =
 102 {
 103         .model =                DISPLAY_MODEL_LCD,
 104         .lcd_width =            16,
 105         .lcd_cmd_reg_addr =     KITTYHAWK_LCD_CMD,
 106         .lcd_data_reg_addr =    KITTYHAWK_LCD_DATA,
 107         .min_cmd_delay =        40,
 108         .reset_cmd1 =           0x80,
 109         .reset_cmd2 =           0xc0,
 110 };
 111
 112
 113 /* direct access to some of the lcd_info variables */
 114 #define LCD_CMD_REG     lcd_info.lcd_cmd_reg_addr
 115 #define LCD_DATA_REG    lcd_info.lcd_data_reg_addr
 116 #define LED_DATA_REG    lcd_info.lcd_cmd_reg_addr       /* LASI & ASP only */
 117
 118
 119 /* ptr to LCD/LED-specific function */
 120 static void (*led_func_ptr) (unsigned char);
 121
 122 #define LED_HASLCD 1
 123 #define LED_NOLCD  0
 124 #ifdef CONFIG_PROC_FS
 125 static int led_proc_read(char *page, char **start, off_t off, int count,
 126         int *eof, void *data)
 127 {
 128         char *out = page;
 129         int len;
 130
 131         switch ((long)data)
 132         {
 133         case LED_NOLCD:
 134                 out += sprintf(out, "Heartbeat: %d\n", led_heartbeat);
 135                 out += sprintf(out, "Disk IO: %d\n", led_diskio);
 136                 out += sprintf(out, "LAN Rx/Tx: %d\n", led_lanrxtx);
 137                 break;
 138         case LED_HASLCD:
 139                 out += sprintf(out, "%s\n", lcd_text);
 140                 break;
 141         default:
 142                 *eof = 1;
 143                 return 0;
 144         }
 145
 146         len = out - page - off;
 147         if (len < count) {
 148                 *eof = 1;
 149                 if (len <= 0) return 0;
 150         } else {
 151                 len = count;
 152         }
 153         *start = page + off;
 154         return len;
 155 }
 156
 157 static int led_proc_write(struct file *file, const char *buf,
 158         unsigned long count, void *data)
 159 {
 160         char *cur, lbuf[count + 1];
 161         int d;
 162
 163         if (!capable(CAP_SYS_ADMIN))
 164                 return -EACCES;
 165
 166         memset(lbuf, 0, count + 1);
 167
 168         if (copy_from_user(lbuf, buf, count))
 169                 return -EFAULT;
 170
 171         cur = lbuf;
 172
 173         /* skip initial spaces */
 174         while (*cur && isspace(*cur))
 175         {
 176                 cur++;
 177         }
 178
 179         switch ((long)data)
 180         {
 181         case LED_NOLCD:
 182                 d = *cur++ - '0';
 183                 if (d != 0 && d != 1) goto parse_error;
 184                 led_heartbeat = d;
 185
 186                 if (*cur++ != ' ') goto parse_error;
 187
 188                 d = *cur++ - '0';
 189                 if (d != 0 && d != 1) goto parse_error;
 190                 led_diskio = d;
 191
 192                 if (*cur++ != ' ') goto parse_error;
 193
 194                 d = *cur++ - '0';
 195                 if (d != 0 && d != 1) goto parse_error;
 196                 led_lanrxtx = d;
 197
 198                 break;
 199         case LED_HASLCD:
 200                 if (*cur && cur[strlen(cur)-1] == '\n')
 201                         cur[strlen(cur)-1] = 0;
 202                 if (*cur == 0)
 203                         cur = lcd_text_default;
 204                 lcd_print(cur);
 205                 break;
 206         default:
 207                 return 0;
 208         }
 209
 210         return count;
 211
 212 parse_error:
 213         if ((long)data == LED_NOLCD)
 214                 printk(KERN_CRIT "Parse error: expect \"n n n\" (n == 0 or 1) for heartbeat,\ndisk io and lan tx/rx indicators\n");
 215         return -EINVAL;
 216 }
 217
 218 static int __init led_create_procfs(void)
 219 {
 220         struct proc_dir_entry *proc_pdc_root = NULL;
 221         struct proc_dir_entry *ent;
 222
 223         if (led_type == -1) return -1;
 224
 225         proc_pdc_root = proc_mkdir("pdc", 0);
 226         if (!proc_pdc_root) return -1;
 227         proc_pdc_root->owner = THIS_MODULE;
 228         ent = create_proc_entry("led", S_IFREG|S_IRUGO|S_IWUSR, proc_pdc_root);
 229         if (!ent) return -1;
 230         ent->nlink = 1;
 231         ent->data = (void *)LED_NOLCD; /* LED */
 232         ent->read_proc = led_proc_read;
 233         ent->write_proc = led_proc_write;
 234         ent->owner = THIS_MODULE;
 235
 236         if (led_type == LED_HASLCD)
 237         {
 238                 ent = create_proc_entry("lcd", S_IFREG|S_IRUGO|S_IWUSR, proc_pdc_root);
 239                 if (!ent) return -1;
 240                 ent->nlink = 1;
 241                 ent->data = (void *)LED_HASLCD; /* LCD */
 242                 ent->read_proc = led_proc_read;
 243                 ent->write_proc = led_proc_write;
 244                 ent->owner = THIS_MODULE;
 245         }
 246
 247         return 0;
 248 }
 249 #endif
 250
 251 /*
 252    **
 253    ** led_ASP_driver()
 254    **
 255  */
 256 #define LED_DATA        0x01    /* data to shift (0:on 1:off) */
 257 #define LED_STROBE      0x02    /* strobe to clock data */
 258 static void led_ASP_driver(unsigned char leds)
 259 {
 260         int i;
 261
 262         leds = ~leds;
 263         for (i = 0; i < 8; i++) {
 264                 unsigned char value;
 265                 value = (leds & 0x80) >> 7;
 266                 gsc_writeb( value,               LED_DATA_REG );
 267                 gsc_writeb( value | LED_STROBE,  LED_DATA_REG );
 268                 leds <<= 1;
 269         }
 270 }
 271
 272
 273 /*
 274    **
 275    ** led_LASI_driver()
 276    **
 277  */
 278 static void led_LASI_driver(unsigned char leds)
 279 {
 280         leds = ~leds;
 281         gsc_writeb( leds, LED_DATA_REG );
 282 }
 283
 284
 285 /*
 286    **
 287    ** led_LCD_driver()
 288    **
 289    ** The logic of the LCD driver is, that we write at every scheduled call
 290    ** only to one of LCD_CMD_REG _or_ LCD_DATA_REG - registers.
 291    ** That way we don't need to let this tasklet busywait for min_cmd_delay
 292    ** milliseconds.
 293    **
 294    ** TODO: check the value of "min_cmd_delay" against the value of HZ.
 295    **
 296  */
 297 static void led_LCD_driver(unsigned char leds)
 298 {
 299         static int last_index;  /* 0:heartbeat, 1:disk, 2:lan_in, 3:lan_out */
 300         static int last_was_cmd;/* 0: CMD was written last, 1: DATA was last */
 301         struct lcd_block *block_ptr;
 302         int value;
 303
 304         switch (last_index) {
 305             case 0:     block_ptr = &lcd_info.heartbeat;
 306                         value = leds & LED_HEARTBEAT;
 307                         break;
 308             case 1:     block_ptr = &lcd_info.disk_io;
 309                         value = leds & LED_DISK_IO;
 310                         break;
 311             case 2:     block_ptr = &lcd_info.lan_rcv;
 312                         value = leds & LED_LAN_RCV;
 313                         break;
 314             case 3:     block_ptr = &lcd_info.lan_tx;
 315                         value = leds & LED_LAN_TX;
 316                         break;
 317             default:    /* should never happen: */
 318                         return;
 319         }
 320
 321         if (last_was_cmd) {
 322             /* write the value to the LCD data port */
 323             gsc_writeb( value ? block_ptr->on : block_ptr->off, LCD_DATA_REG );
 324         } else {
 325             /* write the command-byte to the LCD command register */
 326             gsc_writeb( block_ptr->command, LCD_CMD_REG );
 327         }
 328
 329         /* now update the vars for the next interrupt iteration */
 330         if (++last_was_cmd == 2) { /* switch between cmd & data */
 331             last_was_cmd = 0;
 332             if (++last_index == 4)
 333                 last_index = 0;  /* switch back to heartbeat index */
 334         }
 335 }
 336
 337
 338 /*
 339    **
 340    ** led_get_net_activity()
 341    **
 342    ** calculate if there was TX- or RX-troughput on the network interfaces
 343    ** (analog to dev_get_info() from net/core/dev.c)
 344    **
 345  */
 346 static __inline__ int led_get_net_activity(void)
 347 {
 348 #ifndef CONFIG_NET
 349         return 0;
 350 #else
 351         static unsigned long rx_total_last, tx_total_last;
 352         unsigned long rx_total, tx_total;
 353         struct net_device *dev;
 354         int retval;
 355
 356         rx_total = tx_total = 0;
 357
 358         /* we are running as tasklet, so locking dev_base
 359          * for reading should be OK */
 360         read_lock(&dev_base_lock);
 361         for (dev = dev_base; dev; dev = dev->next) {
 362             struct net_device_stats *stats;
 363             struct in_device *in_dev = __in_dev_get(dev);
 364             if (!in_dev || !in_dev->ifa_list)
 365                 continue;
 366             if (LOOPBACK(in_dev->ifa_list->ifa_local))
 367                 continue;
 368             if (!dev->get_stats)
 369                 continue;
 370             stats = dev->get_stats(dev);
 371             rx_total += stats->rx_packets;
 372             tx_total += stats->tx_packets;
 373         }
 374         read_unlock(&dev_base_lock);
 375
 376         retval = 0;
 377
 378         if (rx_total != rx_total_last) {
 379                 rx_total_last = rx_total;
 380                 retval |= LED_LAN_RCV;
 381         }
 382
 383         if (tx_total != tx_total_last) {
 384                 tx_total_last = tx_total;
 385                 retval |= LED_LAN_TX;
 386         }
 387
 388         return retval;
 389 #endif
 390 }
 391
 392
 393 /*
 394    **
 395    ** led_get_diskio_activity()
 396    **
 397    ** calculate if there was disk-io in the system
 398    **
 399  */
 400 static __inline__ int led_get_diskio_activity(void)
 401 {
 402         static unsigned long last_pgpgin, last_pgpgout;
 403         struct page_state pgstat;
 404         int changed;
 405
 406         get_full_page_state(&pgstat); /* get no of sectors in & out */
 407
 408         /* Just use a very simple calculation here. Do not care about overflow,
 409            since we only want to know if there was activity or not. */
 410         changed = (pgstat.pgpgin != last_pgpgin) || (pgstat.pgpgout != last_pgpgout);
 411         last_pgpgin  = pgstat.pgpgin;
 412         last_pgpgout = pgstat.pgpgout;
 413
 414         return (changed ? LED_DISK_IO : 0);
 415 }
 416
 417
 418
 419 /*
 420    ** led_tasklet_func()
 421    **
 422    ** is scheduled at every timer interrupt from time.c and
 423    ** updates the chassis LCD/LED
 424
 425     TODO:
 426     - display load average (older machines like 715/64 have 4 "free" LED's for that)
 427     - optimizations
 428  */
 429
 430 #define HEARTBEAT_LEN (HZ*6/100)
 431 #define HEARTBEAT_2ND_RANGE_START (HZ*22/100)
 432 #define HEARTBEAT_2ND_RANGE_END   (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN)
 433
 434 #define NORMALIZED_COUNT(count) (count/(HZ/100))
 435
 436 static void led_tasklet_func(unsigned long unused)
 437 {
 438         static unsigned char lastleds;
 439         unsigned char currentleds; /* stores current value of the LEDs */
 440         static unsigned long count; /* static incremented value, not wrapped */
 441         static unsigned long count_HZ; /* counter in range 0..HZ */
 442
 443         /* exit if not initialized */
 444         if (!led_func_ptr)
 445             return;
 446
 447         /* increment the local counters */
 448         ++count;
 449         if (++count_HZ == HZ)
 450             count_HZ = 0;
 451
 452         currentleds = lastleds;
 453
 454         if (led_heartbeat)
 455         {
 456                 /* flash heartbeat-LED like a real heart (2 x short then a long delay) */
 457                 if (count_HZ<HEARTBEAT_LEN ||
 458                     (count_HZ>=HEARTBEAT_2ND_RANGE_START && count_HZ<HEARTBEAT_2ND_RANGE_END))
 459                     currentleds |= LED_HEARTBEAT;
 460                 else
 461                     currentleds &= ~LED_HEARTBEAT;
 462         }
 463
 464         /* look for network activity and flash LEDs respectively */
 465         if (led_lanrxtx && ((NORMALIZED_COUNT(count)+(8/2)) & 7) == 0)
 466         {
 467                 currentleds &= ~(LED_LAN_RCV | LED_LAN_TX);
 468                 currentleds |= led_get_net_activity();
 469         }
 470
 471         /* avoid to calculate diskio-stats at same irq  as netio-stats */
 472         if (led_diskio && (NORMALIZED_COUNT(count) & 7) == 0)
 473         {
 474                 currentleds &= ~LED_DISK_IO;
 475                 currentleds |= led_get_diskio_activity();
 476         }
 477
 478         /* blink all LEDs twice a second if we got an Oops (HPMC) */
 479         if (oops_in_progress) {
 480                 currentleds = (count_HZ<=(HZ/2)) ? 0 : 0xff;
 481         }
 482
 483         /* update the LCD/LEDs */
 484         if (currentleds != lastleds) {
 485             led_func_ptr(currentleds);
 486             lastleds = currentleds;
 487         }
 488 }
 489
 490 /* main led tasklet struct (scheduled from time.c) */
 491 DECLARE_TASKLET_DISABLED(led_tasklet, led_tasklet_func, 0);
 492
 493
 494 /*
 495    ** led_halt()
 496    **
 497    ** called by the reboot notifier chain at shutdown and stops all
 498    ** LED/LCD activities.
 499    **
 500  */
 501
 502 static int led_halt(struct notifier_block *, unsigned long, void *);
 503
 504 static struct notifier_block led_notifier = {
 505         .notifier_call = led_halt,
 506 };
 507
 508 static int led_halt(struct notifier_block *nb, unsigned long event, void *buf)
 509 {
 510         char *txt;
 511
 512         switch (event) {
 513         case SYS_RESTART:       txt = "SYSTEM RESTART";
 514                                 break;
 515         case SYS_HALT:          txt = "SYSTEM HALT";
 516                                 break;
 517         case SYS_POWER_OFF:     txt = "SYSTEM POWER OFF";
 518                                 break;
 519         default:                return NOTIFY_DONE;
 520         }
 521
 522         /* completely stop the LED/LCD tasklet */
 523         tasklet_disable(&led_tasklet);
 524
 525         if (lcd_info.model == DISPLAY_MODEL_LCD)
 526                 lcd_print(txt);
 527         else
 528                 if (led_func_ptr)
 529                         led_func_ptr(0xff); /* turn all LEDs ON */
 530
 531         unregister_reboot_notifier(&led_notifier);
 532         return NOTIFY_OK;
 533 }
 534
 535 /*
 536    ** register_led_driver()
 537    **
 538    ** registers an external LED or LCD for usage by this driver.
 539    ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported.
 540    **
 541  */
 542
 543 int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg)
 544 {
 545         static int initialized;
 546
 547         if (initialized || !data_reg)
 548                 return 1;
 549
 550         lcd_info.model = model;         /* store the values */
 551         LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg;
 552
 553         switch (lcd_info.model) {
 554         case DISPLAY_MODEL_LCD:
 555                 LCD_DATA_REG = data_reg;
 556                 printk(KERN_INFO "LCD display at %lx,%lx registered\n",
 557                         LCD_CMD_REG , LCD_DATA_REG);
 558                 led_func_ptr = led_LCD_driver;
 559                 lcd_print( lcd_text_default );
 560                 led_type = LED_HASLCD;
 561                 break;
 562
 563         case DISPLAY_MODEL_LASI:
 564                 LED_DATA_REG = data_reg;
 565                 led_func_ptr = led_LASI_driver;
 566                 printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG);
 567                 led_type = LED_NOLCD;
 568                 break;
 569
 570         case DISPLAY_MODEL_OLD_ASP:
 571                 LED_DATA_REG = data_reg;
 572                 led_func_ptr = led_ASP_driver;
 573                 printk(KERN_INFO "LED (ASP-style) display at %lx registered\n",
 574                     LED_DATA_REG);
 575                 led_type = LED_NOLCD;
 576                 break;
 577
 578         default:
 579                 printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n",
 580                        __FUNCTION__, lcd_info.model);
 581                 return 1;
 582         }
 583
 584         /* mark the LCD/LED driver now as initialized and
 585          * register to the reboot notifier chain */
 586         initialized++;
 587         register_reboot_notifier(&led_notifier);
 588
 589         /* start the led tasklet for the first time */
 590         tasklet_enable(&led_tasklet);
 591
 592         return 0;
 593 }
 594
 595 /*
 596    ** register_led_regions()
 597    **
 598    ** register_led_regions() registers the LCD/LED regions for /procfs.
 599    ** At bootup - where the initialisation of the LCD/LED normally happens -
 600    ** not all internal structures of request_region() are properly set up,
 601    ** so that we delay the led-registration until after busdevices_init()
 602    ** has been executed.
 603    **
 604  */
 605
 606 void __init register_led_regions(void)
 607 {
 608         switch (lcd_info.model) {
 609         case DISPLAY_MODEL_LCD:
 610                 request_mem_region((unsigned long)LCD_CMD_REG,  1, "lcd_cmd");
 611                 request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data");
 612                 break;
 613         case DISPLAY_MODEL_LASI:
 614         case DISPLAY_MODEL_OLD_ASP:
 615                 request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data");
 616                 break;
 617         }
 618 }
 619
 620
 621 /*
 622    **
 623    ** lcd_print()
 624    **
 625    ** Displays the given string on the LCD-Display of newer machines.
 626    ** lcd_print() disables the timer-based led tasklet during its
 627    ** execution and enables it afterwards again.
 628    **
 629  */
 630 int lcd_print( char *str )
 631 {
 632         int i;
 633
 634         if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD)
 635             return 0;
 636
 637         /* temporarily disable the led tasklet */
 638         tasklet_disable(&led_tasklet);
 639
 640         /* copy display string to buffer for procfs */
 641         strlcpy(lcd_text, str, sizeof(lcd_text));
 642
 643         /* Set LCD Cursor to 1st character */
 644         gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG);
 645         udelay(lcd_info.min_cmd_delay);
 646
 647         /* Print the string */
 648         for (i=0; i < lcd_info.lcd_width; i++) {
 649             if (str && *str)
 650                 gsc_writeb(*str++, LCD_DATA_REG);
 651             else
 652                 gsc_writeb(' ', LCD_DATA_REG);
 653             udelay(lcd_info.min_cmd_delay);
 654         }
 655
 656         /* re-enable the led tasklet */
 657         tasklet_enable(&led_tasklet);
 658
 659         return lcd_info.lcd_width;
 660 }
 661
 662 /*
 663    ** led_init()
 664    **
 665    ** led_init() is called very early in the bootup-process from setup.c
 666    ** and asks the PDC for an usable chassis LCD or LED.
 667    ** If the PDC doesn't return any info, then the LED
 668    ** is detected by lasi.c or asp.c and registered with the
 669    ** above functions lasi_led_init() or asp_led_init().
 670    ** KittyHawk machines have often a buggy PDC, so that
 671    ** we explicitly check for those machines here.
 672  */
 673
 674 int __init led_init(void)
 675 {
 676         struct pdc_chassis_info chassis_info;
 677         int ret;
 678
 679         snprintf(lcd_text_default, sizeof(lcd_text_default),
 680                 "Linux %s", system_utsname.release);
 681
 682         /* Work around the buggy PDC of KittyHawk-machines */
 683         switch (CPU_HVERSION) {
 684         case 0x580:             /* KittyHawk DC2-100 (K100) */
 685         case 0x581:             /* KittyHawk DC3-120 (K210) */
 686         case 0x582:             /* KittyHawk DC3 100 (K400) */
 687         case 0x583:             /* KittyHawk DC3 120 (K410) */
 688         case 0x58B:             /* KittyHawk DC2 100 (K200) */
 689                 printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "
 690                                 "LED detection skipped.\n", __FILE__, CPU_HVERSION);
 691                 goto found;     /* use the preinitialized values of lcd_info */
 692         }
 693
 694         /* initialize the struct, so that we can check for valid return values */
 695         lcd_info.model = DISPLAY_MODEL_NONE;
 696         chassis_info.actcnt = chassis_info.maxcnt = 0;
 697
 698         ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info));
 699         if (ret == PDC_OK) {
 700                 DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), "
 701                          "lcd_width=%d, cmd_delay=%u,\n"
 702                          "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n",
 703                          __FILE__, lcd_info.model,
 704                          (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" :
 705                           (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown",
 706                          lcd_info.lcd_width, lcd_info.min_cmd_delay,
 707                          __FILE__, sizeof(lcd_info),
 708                          chassis_info.actcnt, chassis_info.maxcnt));
 709                 DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n",
 710                         __FILE__, lcd_info.lcd_cmd_reg_addr,
 711                         lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1,
 712                         lcd_info.reset_cmd2, lcd_info.act_enable ));
 713
 714                 /* check the results. Some machines have a buggy PDC */
 715                 if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt)
 716                         goto not_found;
 717
 718                 switch (lcd_info.model) {
 719                 case DISPLAY_MODEL_LCD:         /* LCD display */
 720                         if (chassis_info.actcnt <
 721                                 offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)
 722                                 goto not_found;
 723                         if (!lcd_info.act_enable) {
 724                                 DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n"));
 725                                 goto not_found;
 726                         }
 727                         break;
 728
 729                 case DISPLAY_MODEL_NONE:        /* no LED or LCD available */
 730                         printk(KERN_INFO "PDC reported no LCD or LED.\n");
 731                         goto not_found;
 732
 733                 case DISPLAY_MODEL_LASI:        /* Lasi style 8 bit LED display */
 734                         if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32)
 735                                 goto not_found;
 736                         break;
 737
 738                 default:
 739                         printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n",
 740                                lcd_info.model);
 741                         goto not_found;
 742                 } /* switch() */
 743
 744 found:
 745                 /* register the LCD/LED driver */
 746                 register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG);
 747                 return 0;
 748
 749         } else { /* if() */
 750                 DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret));
 751         }
 752
 753 not_found:
 754         lcd_info.model = DISPLAY_MODEL_NONE;
 755         return 1;
 756 }
 757
 758 #ifdef CONFIG_PROC_FS
 759 module_init(led_create_procfs)
 760 #endif