1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Chassis LCD/LED driver for HP-PARISC workstations 4 * 5 * (c) Copyright 2000 Red Hat Software 6 * (c) Copyright 2000 Helge Deller <hdeller@redhat.com> 7 * (c) Copyright 2001-2009 Helge Deller <deller@gmx.de> 8 * (c) Copyright 2001 Randolph Chung <tausq@debian.org> 9 * 10 * TODO: 11 * - speed-up calculations with inlined assembler 12 * - interface to write to second row of LCD from /proc (if technically possible) 13 * 14 * Changes: 15 * - Audit copy_from_user in led_proc_write. 16 * Daniele Bellucci <bellucda@tiscali.it> 17 * - Switch from using a tasklet to a work queue, so the led_LCD_driver 18 * can sleep. 19 * David Pye <dmp@davidmpye.dyndns.org> 20 */ 21 22 #include <linux/module.h> 23 #include <linux/stddef.h> /* for offsetof() */ 24 #include <linux/init.h> 25 #include <linux/types.h> 26 #include <linux/ioport.h> 27 #include <linux/utsname.h> 28 #include <linux/capability.h> 29 #include <linux/delay.h> 30 #include <linux/netdevice.h> 31 #include <linux/inetdevice.h> 32 #include <linux/in.h> 33 #include <linux/interrupt.h> 34 #include <linux/kernel_stat.h> 35 #include <linux/reboot.h> 36 #include <linux/proc_fs.h> 37 #include <linux/seq_file.h> 38 #include <linux/ctype.h> 39 #include <linux/blkdev.h> 40 #include <linux/workqueue.h> 41 #include <linux/rcupdate.h> 42 #include <asm/io.h> 43 #include <asm/processor.h> 44 #include <asm/hardware.h> 45 #include <asm/param.h> /* HZ */ 46 #include <asm/led.h> 47 #include <asm/pdc.h> 48 #include <linux/uaccess.h> 49 50 /* The control of the LEDs and LCDs on PARISC-machines have to be done 51 completely in software. The necessary calculations are done in a work queue 52 task which is scheduled regularly, and since the calculations may consume a 53 relatively large amount of CPU time, some of the calculations can be 54 turned off with the following variables (controlled via procfs) */ 55 56 static int led_type __read_mostly = -1; 57 static unsigned char lastleds; /* LED state from most recent update */ 58 static unsigned int led_heartbeat __read_mostly = 1; 59 static unsigned int led_diskio __read_mostly = 1; 60 static unsigned int led_lanrxtx __read_mostly = 1; 61 static char lcd_text[32] __read_mostly; 62 static char lcd_text_default[32] __read_mostly; 63 static int lcd_no_led_support __read_mostly = 0; /* KittyHawk doesn't support LED on its LCD */ 64 65 66 static struct workqueue_struct *led_wq; 67 static void led_work_func(struct work_struct *); 68 static DECLARE_DELAYED_WORK(led_task, led_work_func); 69 70 #if 0 71 #define DPRINTK(x) printk x 72 #else 73 #define DPRINTK(x) 74 #endif 75 76 struct lcd_block { 77 unsigned char command; /* stores the command byte */ 78 unsigned char on; /* value for turning LED on */ 79 unsigned char off; /* value for turning LED off */ 80 }; 81 82 /* Structure returned by PDC_RETURN_CHASSIS_INFO */ 83 /* NOTE: we use unsigned long:16 two times, since the following member 84 lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */ 85 struct pdc_chassis_lcd_info_ret_block { 86 unsigned long model:16; /* DISPLAY_MODEL_XXXX */ 87 unsigned long lcd_width:16; /* width of the LCD in chars (DISPLAY_MODEL_LCD only) */ 88 unsigned long lcd_cmd_reg_addr; /* ptr to LCD cmd-register & data ptr for LED */ 89 unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */ 90 unsigned int min_cmd_delay; /* delay in uS after cmd-write (LCD only) */ 91 unsigned char reset_cmd1; /* command #1 for writing LCD string (LCD only) */ 92 unsigned char reset_cmd2; /* command #2 for writing LCD string (LCD only) */ 93 unsigned char act_enable; /* 0 = no activity (LCD only) */ 94 struct lcd_block heartbeat; 95 struct lcd_block disk_io; 96 struct lcd_block lan_rcv; 97 struct lcd_block lan_tx; 98 char _pad; 99 }; 100 101 102 /* LCD_CMD and LCD_DATA for KittyHawk machines */ 103 #define KITTYHAWK_LCD_CMD F_EXTEND(0xf0190000UL) /* 64bit-ready */ 104 #define KITTYHAWK_LCD_DATA (KITTYHAWK_LCD_CMD+1) 105 106 /* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's 107 * HP seems to have used Sharp/Hitachi HD44780 LCDs most of the time. */ 108 static struct pdc_chassis_lcd_info_ret_block 109 lcd_info __attribute__((aligned(8))) __read_mostly = 110 { 111 .model = DISPLAY_MODEL_LCD, 112 .lcd_width = 16, 113 .lcd_cmd_reg_addr = KITTYHAWK_LCD_CMD, 114 .lcd_data_reg_addr = KITTYHAWK_LCD_DATA, 115 .min_cmd_delay = 80, 116 .reset_cmd1 = 0x80, 117 .reset_cmd2 = 0xc0, 118 }; 119 120 121 /* direct access to some of the lcd_info variables */ 122 #define LCD_CMD_REG lcd_info.lcd_cmd_reg_addr 123 #define LCD_DATA_REG lcd_info.lcd_data_reg_addr 124 #define LED_DATA_REG lcd_info.lcd_cmd_reg_addr /* LASI & ASP only */ 125 126 #define LED_HASLCD 1 127 #define LED_NOLCD 0 128 129 /* The workqueue must be created at init-time */ 130 static int start_task(void) 131 { 132 /* Display the default text now */ 133 if (led_type == LED_HASLCD) lcd_print( lcd_text_default ); 134 135 /* KittyHawk has no LED support on its LCD */ 136 if (lcd_no_led_support) return 0; 137 138 /* Create the work queue and queue the LED task */ 139 led_wq = create_singlethread_workqueue("led_wq"); 140 if (!led_wq) 141 return -ENOMEM; 142 143 queue_delayed_work(led_wq, &led_task, 0); 144 145 return 0; 146 } 147 148 device_initcall(start_task); 149 150 /* ptr to LCD/LED-specific function */ 151 static void (*led_func_ptr) (unsigned char) __read_mostly; 152 153 #ifdef CONFIG_PROC_FS 154 static int led_proc_show(struct seq_file *m, void *v) 155 { 156 switch ((long)m->private) 157 { 158 case LED_NOLCD: 159 seq_printf(m, "Heartbeat: %d\n", led_heartbeat); 160 seq_printf(m, "Disk IO: %d\n", led_diskio); 161 seq_printf(m, "LAN Rx/Tx: %d\n", led_lanrxtx); 162 break; 163 case LED_HASLCD: 164 seq_printf(m, "%s\n", lcd_text); 165 break; 166 default: 167 return 0; 168 } 169 return 0; 170 } 171 172 static int led_proc_open(struct inode *inode, struct file *file) 173 { 174 return single_open(file, led_proc_show, pde_data(inode)); 175 } 176 177 178 static ssize_t led_proc_write(struct file *file, const char __user *buf, 179 size_t count, loff_t *pos) 180 { 181 void *data = pde_data(file_inode(file)); 182 char *cur, lbuf[32]; 183 int d; 184 185 if (!capable(CAP_SYS_ADMIN)) 186 return -EACCES; 187 188 if (count >= sizeof(lbuf)) 189 count = sizeof(lbuf)-1; 190 191 if (copy_from_user(lbuf, buf, count)) 192 return -EFAULT; 193 lbuf[count] = 0; 194 195 cur = lbuf; 196 197 switch ((long)data) 198 { 199 case LED_NOLCD: 200 d = *cur++ - '0'; 201 if (d != 0 && d != 1) goto parse_error; 202 led_heartbeat = d; 203 204 if (*cur++ != ' ') goto parse_error; 205 206 d = *cur++ - '0'; 207 if (d != 0 && d != 1) goto parse_error; 208 led_diskio = d; 209 210 if (*cur++ != ' ') goto parse_error; 211 212 d = *cur++ - '0'; 213 if (d != 0 && d != 1) goto parse_error; 214 led_lanrxtx = d; 215 216 break; 217 case LED_HASLCD: 218 if (*cur && cur[strlen(cur)-1] == '\n') 219 cur[strlen(cur)-1] = 0; 220 if (*cur == 0) 221 cur = lcd_text_default; 222 lcd_print(cur); 223 break; 224 default: 225 return 0; 226 } 227 228 return count; 229 230 parse_error: 231 if ((long)data == LED_NOLCD) 232 printk(KERN_CRIT "Parse error: expect \"n n n\" (n == 0 or 1) for heartbeat,\ndisk io and lan tx/rx indicators\n"); 233 return -EINVAL; 234 } 235 236 static const struct proc_ops led_proc_ops = { 237 .proc_open = led_proc_open, 238 .proc_read = seq_read, 239 .proc_lseek = seq_lseek, 240 .proc_release = single_release, 241 .proc_write = led_proc_write, 242 }; 243 244 static int __init led_create_procfs(void) 245 { 246 struct proc_dir_entry *proc_pdc_root = NULL; 247 struct proc_dir_entry *ent; 248 249 if (led_type == -1) return -1; 250 251 proc_pdc_root = proc_mkdir("pdc", NULL); 252 if (!proc_pdc_root) return -1; 253 254 if (!lcd_no_led_support) 255 { 256 ent = proc_create_data("led", 0644, proc_pdc_root, 257 &led_proc_ops, (void *)LED_NOLCD); /* LED */ 258 if (!ent) return -1; 259 } 260 261 if (led_type == LED_HASLCD) 262 { 263 ent = proc_create_data("lcd", 0644, proc_pdc_root, 264 &led_proc_ops, (void *)LED_HASLCD); /* LCD */ 265 if (!ent) return -1; 266 } 267 268 return 0; 269 } 270 #endif 271 272 /* 273 ** 274 ** led_ASP_driver() 275 ** 276 */ 277 #define LED_DATA 0x01 /* data to shift (0:on 1:off) */ 278 #define LED_STROBE 0x02 /* strobe to clock data */ 279 static void led_ASP_driver(unsigned char leds) 280 { 281 int i; 282 283 leds = ~leds; 284 for (i = 0; i < 8; i++) { 285 unsigned char value; 286 value = (leds & 0x80) >> 7; 287 gsc_writeb( value, LED_DATA_REG ); 288 gsc_writeb( value | LED_STROBE, LED_DATA_REG ); 289 leds <<= 1; 290 } 291 } 292 293 294 /* 295 ** 296 ** led_LASI_driver() 297 ** 298 */ 299 static void led_LASI_driver(unsigned char leds) 300 { 301 leds = ~leds; 302 gsc_writeb( leds, LED_DATA_REG ); 303 } 304 305 306 /* 307 ** 308 ** led_LCD_driver() 309 ** 310 */ 311 static void led_LCD_driver(unsigned char leds) 312 { 313 static int i; 314 static unsigned char mask[4] = { LED_HEARTBEAT, LED_DISK_IO, 315 LED_LAN_RCV, LED_LAN_TX }; 316 317 static struct lcd_block * blockp[4] = { 318 &lcd_info.heartbeat, 319 &lcd_info.disk_io, 320 &lcd_info.lan_rcv, 321 &lcd_info.lan_tx 322 }; 323 324 /* Convert min_cmd_delay to milliseconds */ 325 unsigned int msec_cmd_delay = 1 + (lcd_info.min_cmd_delay / 1000); 326 327 for (i=0; i<4; ++i) 328 { 329 if ((leds & mask[i]) != (lastleds & mask[i])) 330 { 331 gsc_writeb( blockp[i]->command, LCD_CMD_REG ); 332 msleep(msec_cmd_delay); 333 334 gsc_writeb( leds & mask[i] ? blockp[i]->on : 335 blockp[i]->off, LCD_DATA_REG ); 336 msleep(msec_cmd_delay); 337 } 338 } 339 } 340 341 342 /* 343 ** 344 ** led_get_net_activity() 345 ** 346 ** calculate if there was TX- or RX-throughput on the network interfaces 347 ** (analog to dev_get_info() from net/core/dev.c) 348 ** 349 */ 350 static __inline__ int led_get_net_activity(void) 351 { 352 #ifndef CONFIG_NET 353 return 0; 354 #else 355 static u64 rx_total_last, tx_total_last; 356 u64 rx_total, tx_total; 357 struct net_device *dev; 358 int retval; 359 360 rx_total = tx_total = 0; 361 362 /* we are running as a workqueue task, so we can use an RCU lookup */ 363 rcu_read_lock(); 364 for_each_netdev_rcu(&init_net, dev) { 365 const struct rtnl_link_stats64 *stats; 366 struct rtnl_link_stats64 temp; 367 struct in_device *in_dev = __in_dev_get_rcu(dev); 368 if (!in_dev || !in_dev->ifa_list) 369 continue; 370 if (ipv4_is_loopback(in_dev->ifa_list->ifa_local)) 371 continue; 372 stats = dev_get_stats(dev, &temp); 373 rx_total += stats->rx_packets; 374 tx_total += stats->tx_packets; 375 } 376 rcu_read_unlock(); 377 378 retval = 0; 379 380 if (rx_total != rx_total_last) { 381 rx_total_last = rx_total; 382 retval |= LED_LAN_RCV; 383 } 384 385 if (tx_total != tx_total_last) { 386 tx_total_last = tx_total; 387 retval |= LED_LAN_TX; 388 } 389 390 return retval; 391 #endif 392 } 393 394 395 /* 396 ** 397 ** led_get_diskio_activity() 398 ** 399 ** calculate if there was disk-io in the system 400 ** 401 */ 402 static __inline__ int led_get_diskio_activity(void) 403 { 404 static unsigned long last_pgpgin, last_pgpgout; 405 unsigned long events[NR_VM_EVENT_ITEMS]; 406 int changed; 407 408 all_vm_events(events); 409 410 /* Just use a very simple calculation here. Do not care about overflow, 411 since we only want to know if there was activity or not. */ 412 changed = (events[PGPGIN] != last_pgpgin) || 413 (events[PGPGOUT] != last_pgpgout); 414 last_pgpgin = events[PGPGIN]; 415 last_pgpgout = events[PGPGOUT]; 416 417 return (changed ? LED_DISK_IO : 0); 418 } 419 420 421 422 /* 423 ** led_work_func() 424 ** 425 ** manages when and which chassis LCD/LED gets updated 426 427 TODO: 428 - display load average (older machines like 715/64 have 4 "free" LED's for that) 429 - optimizations 430 */ 431 432 #define HEARTBEAT_LEN (HZ*10/100) 433 #define HEARTBEAT_2ND_RANGE_START (HZ*28/100) 434 #define HEARTBEAT_2ND_RANGE_END (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN) 435 436 #define LED_UPDATE_INTERVAL (1 + (HZ*19/1000)) 437 438 static void led_work_func (struct work_struct *unused) 439 { 440 static unsigned long last_jiffies; 441 static unsigned long count_HZ; /* counter in range 0..HZ */ 442 unsigned char currentleds = 0; /* stores current value of the LEDs */ 443 444 /* exit if not initialized */ 445 if (!led_func_ptr) 446 return; 447 448 /* increment the heartbeat timekeeper */ 449 count_HZ += jiffies - last_jiffies; 450 last_jiffies = jiffies; 451 if (count_HZ >= HZ) 452 count_HZ = 0; 453 454 if (likely(led_heartbeat)) 455 { 456 /* flash heartbeat-LED like a real heart 457 * (2 x short then a long delay) 458 */ 459 if (count_HZ < HEARTBEAT_LEN || 460 (count_HZ >= HEARTBEAT_2ND_RANGE_START && 461 count_HZ < HEARTBEAT_2ND_RANGE_END)) 462 currentleds |= LED_HEARTBEAT; 463 } 464 465 if (likely(led_lanrxtx)) currentleds |= led_get_net_activity(); 466 if (likely(led_diskio)) currentleds |= led_get_diskio_activity(); 467 468 /* blink LEDs if we got an Oops (HPMC) */ 469 if (unlikely(oops_in_progress)) { 470 if (boot_cpu_data.cpu_type >= pcxl2) { 471 /* newer machines don't have loadavg. LEDs, so we 472 * let all LEDs blink twice per second instead */ 473 currentleds = (count_HZ <= (HZ/2)) ? 0 : 0xff; 474 } else { 475 /* old machines: blink loadavg. LEDs twice per second */ 476 if (count_HZ <= (HZ/2)) 477 currentleds &= ~(LED4|LED5|LED6|LED7); 478 else 479 currentleds |= (LED4|LED5|LED6|LED7); 480 } 481 } 482 483 if (currentleds != lastleds) 484 { 485 led_func_ptr(currentleds); /* Update the LCD/LEDs */ 486 lastleds = currentleds; 487 } 488 489 queue_delayed_work(led_wq, &led_task, LED_UPDATE_INTERVAL); 490 } 491 492 /* 493 ** led_halt() 494 ** 495 ** called by the reboot notifier chain at shutdown and stops all 496 ** LED/LCD activities. 497 ** 498 */ 499 500 static int led_halt(struct notifier_block *, unsigned long, void *); 501 502 static struct notifier_block led_notifier = { 503 .notifier_call = led_halt, 504 }; 505 static int notifier_disabled = 0; 506 507 static int led_halt(struct notifier_block *nb, unsigned long event, void *buf) 508 { 509 char *txt; 510 511 if (notifier_disabled) 512 return NOTIFY_OK; 513 514 notifier_disabled = 1; 515 switch (event) { 516 case SYS_RESTART: txt = "SYSTEM RESTART"; 517 break; 518 case SYS_HALT: txt = "SYSTEM HALT"; 519 break; 520 case SYS_POWER_OFF: txt = "SYSTEM POWER OFF"; 521 break; 522 default: return NOTIFY_DONE; 523 } 524 525 /* Cancel the work item and delete the queue */ 526 if (led_wq) { 527 cancel_delayed_work_sync(&led_task); 528 destroy_workqueue(led_wq); 529 led_wq = NULL; 530 } 531 532 if (lcd_info.model == DISPLAY_MODEL_LCD) 533 lcd_print(txt); 534 else 535 if (led_func_ptr) 536 led_func_ptr(0xff); /* turn all LEDs ON */ 537 538 return NOTIFY_OK; 539 } 540 541 /* 542 ** register_led_driver() 543 ** 544 ** registers an external LED or LCD for usage by this driver. 545 ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported. 546 ** 547 */ 548 549 int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg) 550 { 551 static int initialized; 552 553 if (initialized || !data_reg) 554 return 1; 555 556 lcd_info.model = model; /* store the values */ 557 LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg; 558 559 switch (lcd_info.model) { 560 case DISPLAY_MODEL_LCD: 561 LCD_DATA_REG = data_reg; 562 printk(KERN_INFO "LCD display at %lx,%lx registered\n", 563 LCD_CMD_REG , LCD_DATA_REG); 564 led_func_ptr = led_LCD_driver; 565 led_type = LED_HASLCD; 566 break; 567 568 case DISPLAY_MODEL_LASI: 569 /* Skip to register LED in QEMU */ 570 if (running_on_qemu) 571 return 1; 572 LED_DATA_REG = data_reg; 573 led_func_ptr = led_LASI_driver; 574 printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG); 575 led_type = LED_NOLCD; 576 break; 577 578 case DISPLAY_MODEL_OLD_ASP: 579 LED_DATA_REG = data_reg; 580 led_func_ptr = led_ASP_driver; 581 printk(KERN_INFO "LED (ASP-style) display at %lx registered\n", 582 LED_DATA_REG); 583 led_type = LED_NOLCD; 584 break; 585 586 default: 587 printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n", 588 __func__, lcd_info.model); 589 return 1; 590 } 591 592 /* mark the LCD/LED driver now as initialized and 593 * register to the reboot notifier chain */ 594 initialized++; 595 register_reboot_notifier(&led_notifier); 596 597 /* Ensure the work is queued */ 598 if (led_wq) { 599 queue_delayed_work(led_wq, &led_task, 0); 600 } 601 602 return 0; 603 } 604 605 /* 606 ** register_led_regions() 607 ** 608 ** register_led_regions() registers the LCD/LED regions for /procfs. 609 ** At bootup - where the initialisation of the LCD/LED normally happens - 610 ** not all internal structures of request_region() are properly set up, 611 ** so that we delay the led-registration until after busdevices_init() 612 ** has been executed. 613 ** 614 */ 615 616 void __init register_led_regions(void) 617 { 618 switch (lcd_info.model) { 619 case DISPLAY_MODEL_LCD: 620 request_mem_region((unsigned long)LCD_CMD_REG, 1, "lcd_cmd"); 621 request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data"); 622 break; 623 case DISPLAY_MODEL_LASI: 624 case DISPLAY_MODEL_OLD_ASP: 625 request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data"); 626 break; 627 } 628 } 629 630 631 /* 632 ** 633 ** lcd_print() 634 ** 635 ** Displays the given string on the LCD-Display of newer machines. 636 ** lcd_print() disables/enables the timer-based led work queue to 637 ** avoid a race condition while writing the CMD/DATA register pair. 638 ** 639 */ 640 int lcd_print( const char *str ) 641 { 642 int i; 643 644 if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD) 645 return 0; 646 647 /* temporarily disable the led work task */ 648 if (led_wq) 649 cancel_delayed_work_sync(&led_task); 650 651 /* copy display string to buffer for procfs */ 652 strscpy(lcd_text, str, sizeof(lcd_text)); 653 654 /* Set LCD Cursor to 1st character */ 655 gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG); 656 udelay(lcd_info.min_cmd_delay); 657 658 /* Print the string */ 659 for (i=0; i < lcd_info.lcd_width; i++) { 660 if (str && *str) 661 gsc_writeb(*str++, LCD_DATA_REG); 662 else 663 gsc_writeb(' ', LCD_DATA_REG); 664 udelay(lcd_info.min_cmd_delay); 665 } 666 667 /* re-queue the work */ 668 if (led_wq) { 669 queue_delayed_work(led_wq, &led_task, 0); 670 } 671 672 return lcd_info.lcd_width; 673 } 674 675 /* 676 ** led_init() 677 ** 678 ** led_init() is called very early in the bootup-process from setup.c 679 ** and asks the PDC for an usable chassis LCD or LED. 680 ** If the PDC doesn't return any info, then the LED 681 ** is detected by lasi.c or asp.c and registered with the 682 ** above functions lasi_led_init() or asp_led_init(). 683 ** KittyHawk machines have often a buggy PDC, so that 684 ** we explicitly check for those machines here. 685 */ 686 687 int __init led_init(void) 688 { 689 struct pdc_chassis_info chassis_info; 690 int ret; 691 692 snprintf(lcd_text_default, sizeof(lcd_text_default), 693 "Linux %s", init_utsname()->release); 694 695 /* Work around the buggy PDC of KittyHawk-machines */ 696 switch (CPU_HVERSION) { 697 case 0x580: /* KittyHawk DC2-100 (K100) */ 698 case 0x581: /* KittyHawk DC3-120 (K210) */ 699 case 0x582: /* KittyHawk DC3 100 (K400) */ 700 case 0x583: /* KittyHawk DC3 120 (K410) */ 701 case 0x58B: /* KittyHawk DC2 100 (K200) */ 702 printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, " 703 "LED detection skipped.\n", __FILE__, CPU_HVERSION); 704 lcd_no_led_support = 1; 705 goto found; /* use the preinitialized values of lcd_info */ 706 } 707 708 /* initialize the struct, so that we can check for valid return values */ 709 lcd_info.model = DISPLAY_MODEL_NONE; 710 chassis_info.actcnt = chassis_info.maxcnt = 0; 711 712 ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info)); 713 if (ret == PDC_OK) { 714 DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), " 715 "lcd_width=%d, cmd_delay=%u,\n" 716 "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n", 717 __FILE__, lcd_info.model, 718 (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" : 719 (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown", 720 lcd_info.lcd_width, lcd_info.min_cmd_delay, 721 __FILE__, sizeof(lcd_info), 722 chassis_info.actcnt, chassis_info.maxcnt)); 723 DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n", 724 __FILE__, lcd_info.lcd_cmd_reg_addr, 725 lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1, 726 lcd_info.reset_cmd2, lcd_info.act_enable )); 727 728 /* check the results. Some machines have a buggy PDC */ 729 if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt) 730 goto not_found; 731 732 switch (lcd_info.model) { 733 case DISPLAY_MODEL_LCD: /* LCD display */ 734 if (chassis_info.actcnt < 735 offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1) 736 goto not_found; 737 if (!lcd_info.act_enable) { 738 DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n")); 739 goto not_found; 740 } 741 break; 742 743 case DISPLAY_MODEL_NONE: /* no LED or LCD available */ 744 printk(KERN_INFO "PDC reported no LCD or LED.\n"); 745 goto not_found; 746 747 case DISPLAY_MODEL_LASI: /* Lasi style 8 bit LED display */ 748 if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32) 749 goto not_found; 750 break; 751 752 default: 753 printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n", 754 lcd_info.model); 755 goto not_found; 756 } /* switch() */ 757 758 found: 759 /* register the LCD/LED driver */ 760 register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG); 761 return 0; 762 763 } else { /* if() */ 764 DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret)); 765 } 766 767 not_found: 768 lcd_info.model = DISPLAY_MODEL_NONE; 769 return 1; 770 } 771 772 static void __exit led_exit(void) 773 { 774 unregister_reboot_notifier(&led_notifier); 775 return; 776 } 777 778 #ifdef CONFIG_PROC_FS 779 module_init(led_create_procfs) 780 #endif 781