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 queue_delayed_work(led_wq, &led_task, 0); 141 142 return 0; 143 } 144 145 device_initcall(start_task); 146 147 /* ptr to LCD/LED-specific function */ 148 static void (*led_func_ptr) (unsigned char) __read_mostly; 149 150 #ifdef CONFIG_PROC_FS 151 static int led_proc_show(struct seq_file *m, void *v) 152 { 153 switch ((long)m->private) 154 { 155 case LED_NOLCD: 156 seq_printf(m, "Heartbeat: %d\n", led_heartbeat); 157 seq_printf(m, "Disk IO: %d\n", led_diskio); 158 seq_printf(m, "LAN Rx/Tx: %d\n", led_lanrxtx); 159 break; 160 case LED_HASLCD: 161 seq_printf(m, "%s\n", lcd_text); 162 break; 163 default: 164 return 0; 165 } 166 return 0; 167 } 168 169 static int led_proc_open(struct inode *inode, struct file *file) 170 { 171 return single_open(file, led_proc_show, PDE_DATA(inode)); 172 } 173 174 175 static ssize_t led_proc_write(struct file *file, const char __user *buf, 176 size_t count, loff_t *pos) 177 { 178 void *data = PDE_DATA(file_inode(file)); 179 char *cur, lbuf[32]; 180 int d; 181 182 if (!capable(CAP_SYS_ADMIN)) 183 return -EACCES; 184 185 if (count >= sizeof(lbuf)) 186 count = sizeof(lbuf)-1; 187 188 if (copy_from_user(lbuf, buf, count)) 189 return -EFAULT; 190 lbuf[count] = 0; 191 192 cur = lbuf; 193 194 switch ((long)data) 195 { 196 case LED_NOLCD: 197 d = *cur++ - '0'; 198 if (d != 0 && d != 1) goto parse_error; 199 led_heartbeat = d; 200 201 if (*cur++ != ' ') goto parse_error; 202 203 d = *cur++ - '0'; 204 if (d != 0 && d != 1) goto parse_error; 205 led_diskio = d; 206 207 if (*cur++ != ' ') goto parse_error; 208 209 d = *cur++ - '0'; 210 if (d != 0 && d != 1) goto parse_error; 211 led_lanrxtx = d; 212 213 break; 214 case LED_HASLCD: 215 if (*cur && cur[strlen(cur)-1] == '\n') 216 cur[strlen(cur)-1] = 0; 217 if (*cur == 0) 218 cur = lcd_text_default; 219 lcd_print(cur); 220 break; 221 default: 222 return 0; 223 } 224 225 return count; 226 227 parse_error: 228 if ((long)data == LED_NOLCD) 229 printk(KERN_CRIT "Parse error: expect \"n n n\" (n == 0 or 1) for heartbeat,\ndisk io and lan tx/rx indicators\n"); 230 return -EINVAL; 231 } 232 233 static const struct proc_ops led_proc_ops = { 234 .proc_open = led_proc_open, 235 .proc_read = seq_read, 236 .proc_lseek = seq_lseek, 237 .proc_release = single_release, 238 .proc_write = led_proc_write, 239 }; 240 241 static int __init led_create_procfs(void) 242 { 243 struct proc_dir_entry *proc_pdc_root = NULL; 244 struct proc_dir_entry *ent; 245 246 if (led_type == -1) return -1; 247 248 proc_pdc_root = proc_mkdir("pdc", NULL); 249 if (!proc_pdc_root) return -1; 250 251 if (!lcd_no_led_support) 252 { 253 ent = proc_create_data("led", S_IRUGO|S_IWUSR, proc_pdc_root, 254 &led_proc_ops, (void *)LED_NOLCD); /* LED */ 255 if (!ent) return -1; 256 } 257 258 if (led_type == LED_HASLCD) 259 { 260 ent = proc_create_data("lcd", S_IRUGO|S_IWUSR, proc_pdc_root, 261 &led_proc_ops, (void *)LED_HASLCD); /* LCD */ 262 if (!ent) return -1; 263 } 264 265 return 0; 266 } 267 #endif 268 269 /* 270 ** 271 ** led_ASP_driver() 272 ** 273 */ 274 #define LED_DATA 0x01 /* data to shift (0:on 1:off) */ 275 #define LED_STROBE 0x02 /* strobe to clock data */ 276 static void led_ASP_driver(unsigned char leds) 277 { 278 int i; 279 280 leds = ~leds; 281 for (i = 0; i < 8; i++) { 282 unsigned char value; 283 value = (leds & 0x80) >> 7; 284 gsc_writeb( value, LED_DATA_REG ); 285 gsc_writeb( value | LED_STROBE, LED_DATA_REG ); 286 leds <<= 1; 287 } 288 } 289 290 291 /* 292 ** 293 ** led_LASI_driver() 294 ** 295 */ 296 static void led_LASI_driver(unsigned char leds) 297 { 298 leds = ~leds; 299 gsc_writeb( leds, LED_DATA_REG ); 300 } 301 302 303 /* 304 ** 305 ** led_LCD_driver() 306 ** 307 */ 308 static void led_LCD_driver(unsigned char leds) 309 { 310 static int i; 311 static unsigned char mask[4] = { LED_HEARTBEAT, LED_DISK_IO, 312 LED_LAN_RCV, LED_LAN_TX }; 313 314 static struct lcd_block * blockp[4] = { 315 &lcd_info.heartbeat, 316 &lcd_info.disk_io, 317 &lcd_info.lan_rcv, 318 &lcd_info.lan_tx 319 }; 320 321 /* Convert min_cmd_delay to milliseconds */ 322 unsigned int msec_cmd_delay = 1 + (lcd_info.min_cmd_delay / 1000); 323 324 for (i=0; i<4; ++i) 325 { 326 if ((leds & mask[i]) != (lastleds & mask[i])) 327 { 328 gsc_writeb( blockp[i]->command, LCD_CMD_REG ); 329 msleep(msec_cmd_delay); 330 331 gsc_writeb( leds & mask[i] ? blockp[i]->on : 332 blockp[i]->off, LCD_DATA_REG ); 333 msleep(msec_cmd_delay); 334 } 335 } 336 } 337 338 339 /* 340 ** 341 ** led_get_net_activity() 342 ** 343 ** calculate if there was TX- or RX-throughput on the network interfaces 344 ** (analog to dev_get_info() from net/core/dev.c) 345 ** 346 */ 347 static __inline__ int led_get_net_activity(void) 348 { 349 #ifndef CONFIG_NET 350 return 0; 351 #else 352 static u64 rx_total_last, tx_total_last; 353 u64 rx_total, tx_total; 354 struct net_device *dev; 355 int retval; 356 357 rx_total = tx_total = 0; 358 359 /* we are running as a workqueue task, so we can use an RCU lookup */ 360 rcu_read_lock(); 361 for_each_netdev_rcu(&init_net, dev) { 362 const struct rtnl_link_stats64 *stats; 363 struct rtnl_link_stats64 temp; 364 struct in_device *in_dev = __in_dev_get_rcu(dev); 365 if (!in_dev || !in_dev->ifa_list) 366 continue; 367 if (ipv4_is_loopback(in_dev->ifa_list->ifa_local)) 368 continue; 369 stats = dev_get_stats(dev, &temp); 370 rx_total += stats->rx_packets; 371 tx_total += stats->tx_packets; 372 } 373 rcu_read_unlock(); 374 375 retval = 0; 376 377 if (rx_total != rx_total_last) { 378 rx_total_last = rx_total; 379 retval |= LED_LAN_RCV; 380 } 381 382 if (tx_total != tx_total_last) { 383 tx_total_last = tx_total; 384 retval |= LED_LAN_TX; 385 } 386 387 return retval; 388 #endif 389 } 390 391 392 /* 393 ** 394 ** led_get_diskio_activity() 395 ** 396 ** calculate if there was disk-io in the system 397 ** 398 */ 399 static __inline__ int led_get_diskio_activity(void) 400 { 401 static unsigned long last_pgpgin, last_pgpgout; 402 unsigned long events[NR_VM_EVENT_ITEMS]; 403 int changed; 404 405 all_vm_events(events); 406 407 /* Just use a very simple calculation here. Do not care about overflow, 408 since we only want to know if there was activity or not. */ 409 changed = (events[PGPGIN] != last_pgpgin) || 410 (events[PGPGOUT] != last_pgpgout); 411 last_pgpgin = events[PGPGIN]; 412 last_pgpgout = events[PGPGOUT]; 413 414 return (changed ? LED_DISK_IO : 0); 415 } 416 417 418 419 /* 420 ** led_work_func() 421 ** 422 ** manages when and which chassis LCD/LED gets updated 423 424 TODO: 425 - display load average (older machines like 715/64 have 4 "free" LED's for that) 426 - optimizations 427 */ 428 429 #define HEARTBEAT_LEN (HZ*10/100) 430 #define HEARTBEAT_2ND_RANGE_START (HZ*28/100) 431 #define HEARTBEAT_2ND_RANGE_END (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN) 432 433 #define LED_UPDATE_INTERVAL (1 + (HZ*19/1000)) 434 435 static void led_work_func (struct work_struct *unused) 436 { 437 static unsigned long last_jiffies; 438 static unsigned long count_HZ; /* counter in range 0..HZ */ 439 unsigned char currentleds = 0; /* stores current value of the LEDs */ 440 441 /* exit if not initialized */ 442 if (!led_func_ptr) 443 return; 444 445 /* increment the heartbeat timekeeper */ 446 count_HZ += jiffies - last_jiffies; 447 last_jiffies = jiffies; 448 if (count_HZ >= HZ) 449 count_HZ = 0; 450 451 if (likely(led_heartbeat)) 452 { 453 /* flash heartbeat-LED like a real heart 454 * (2 x short then a long delay) 455 */ 456 if (count_HZ < HEARTBEAT_LEN || 457 (count_HZ >= HEARTBEAT_2ND_RANGE_START && 458 count_HZ < HEARTBEAT_2ND_RANGE_END)) 459 currentleds |= LED_HEARTBEAT; 460 } 461 462 if (likely(led_lanrxtx)) currentleds |= led_get_net_activity(); 463 if (likely(led_diskio)) currentleds |= led_get_diskio_activity(); 464 465 /* blink LEDs if we got an Oops (HPMC) */ 466 if (unlikely(oops_in_progress)) { 467 if (boot_cpu_data.cpu_type >= pcxl2) { 468 /* newer machines don't have loadavg. LEDs, so we 469 * let all LEDs blink twice per second instead */ 470 currentleds = (count_HZ <= (HZ/2)) ? 0 : 0xff; 471 } else { 472 /* old machines: blink loadavg. LEDs twice per second */ 473 if (count_HZ <= (HZ/2)) 474 currentleds &= ~(LED4|LED5|LED6|LED7); 475 else 476 currentleds |= (LED4|LED5|LED6|LED7); 477 } 478 } 479 480 if (currentleds != lastleds) 481 { 482 led_func_ptr(currentleds); /* Update the LCD/LEDs */ 483 lastleds = currentleds; 484 } 485 486 queue_delayed_work(led_wq, &led_task, LED_UPDATE_INTERVAL); 487 } 488 489 /* 490 ** led_halt() 491 ** 492 ** called by the reboot notifier chain at shutdown and stops all 493 ** LED/LCD activities. 494 ** 495 */ 496 497 static int led_halt(struct notifier_block *, unsigned long, void *); 498 499 static struct notifier_block led_notifier = { 500 .notifier_call = led_halt, 501 }; 502 static int notifier_disabled = 0; 503 504 static int led_halt(struct notifier_block *nb, unsigned long event, void *buf) 505 { 506 char *txt; 507 508 if (notifier_disabled) 509 return NOTIFY_OK; 510 511 notifier_disabled = 1; 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 /* Cancel the work item and delete the queue */ 523 if (led_wq) { 524 cancel_delayed_work_sync(&led_task); 525 destroy_workqueue(led_wq); 526 led_wq = NULL; 527 } 528 529 if (lcd_info.model == DISPLAY_MODEL_LCD) 530 lcd_print(txt); 531 else 532 if (led_func_ptr) 533 led_func_ptr(0xff); /* turn all LEDs ON */ 534 535 return NOTIFY_OK; 536 } 537 538 /* 539 ** register_led_driver() 540 ** 541 ** registers an external LED or LCD for usage by this driver. 542 ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported. 543 ** 544 */ 545 546 int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg) 547 { 548 static int initialized; 549 550 if (initialized || !data_reg) 551 return 1; 552 553 lcd_info.model = model; /* store the values */ 554 LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg; 555 556 switch (lcd_info.model) { 557 case DISPLAY_MODEL_LCD: 558 LCD_DATA_REG = data_reg; 559 printk(KERN_INFO "LCD display at %lx,%lx registered\n", 560 LCD_CMD_REG , LCD_DATA_REG); 561 led_func_ptr = led_LCD_driver; 562 led_type = LED_HASLCD; 563 break; 564 565 case DISPLAY_MODEL_LASI: 566 /* Skip to register LED in QEMU */ 567 if (running_on_qemu) 568 return 1; 569 LED_DATA_REG = data_reg; 570 led_func_ptr = led_LASI_driver; 571 printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG); 572 led_type = LED_NOLCD; 573 break; 574 575 case DISPLAY_MODEL_OLD_ASP: 576 LED_DATA_REG = data_reg; 577 led_func_ptr = led_ASP_driver; 578 printk(KERN_INFO "LED (ASP-style) display at %lx registered\n", 579 LED_DATA_REG); 580 led_type = LED_NOLCD; 581 break; 582 583 default: 584 printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n", 585 __func__, lcd_info.model); 586 return 1; 587 } 588 589 /* mark the LCD/LED driver now as initialized and 590 * register to the reboot notifier chain */ 591 initialized++; 592 register_reboot_notifier(&led_notifier); 593 594 /* Ensure the work is queued */ 595 if (led_wq) { 596 queue_delayed_work(led_wq, &led_task, 0); 597 } 598 599 return 0; 600 } 601 602 /* 603 ** register_led_regions() 604 ** 605 ** register_led_regions() registers the LCD/LED regions for /procfs. 606 ** At bootup - where the initialisation of the LCD/LED normally happens - 607 ** not all internal structures of request_region() are properly set up, 608 ** so that we delay the led-registration until after busdevices_init() 609 ** has been executed. 610 ** 611 */ 612 613 void __init register_led_regions(void) 614 { 615 switch (lcd_info.model) { 616 case DISPLAY_MODEL_LCD: 617 request_mem_region((unsigned long)LCD_CMD_REG, 1, "lcd_cmd"); 618 request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data"); 619 break; 620 case DISPLAY_MODEL_LASI: 621 case DISPLAY_MODEL_OLD_ASP: 622 request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data"); 623 break; 624 } 625 } 626 627 628 /* 629 ** 630 ** lcd_print() 631 ** 632 ** Displays the given string on the LCD-Display of newer machines. 633 ** lcd_print() disables/enables the timer-based led work queue to 634 ** avoid a race condition while writing the CMD/DATA register pair. 635 ** 636 */ 637 int lcd_print( const char *str ) 638 { 639 int i; 640 641 if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD) 642 return 0; 643 644 /* temporarily disable the led work task */ 645 if (led_wq) 646 cancel_delayed_work_sync(&led_task); 647 648 /* copy display string to buffer for procfs */ 649 strlcpy(lcd_text, str, sizeof(lcd_text)); 650 651 /* Set LCD Cursor to 1st character */ 652 gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG); 653 udelay(lcd_info.min_cmd_delay); 654 655 /* Print the string */ 656 for (i=0; i < lcd_info.lcd_width; i++) { 657 if (str && *str) 658 gsc_writeb(*str++, LCD_DATA_REG); 659 else 660 gsc_writeb(' ', LCD_DATA_REG); 661 udelay(lcd_info.min_cmd_delay); 662 } 663 664 /* re-queue the work */ 665 if (led_wq) { 666 queue_delayed_work(led_wq, &led_task, 0); 667 } 668 669 return lcd_info.lcd_width; 670 } 671 672 /* 673 ** led_init() 674 ** 675 ** led_init() is called very early in the bootup-process from setup.c 676 ** and asks the PDC for an usable chassis LCD or LED. 677 ** If the PDC doesn't return any info, then the LED 678 ** is detected by lasi.c or asp.c and registered with the 679 ** above functions lasi_led_init() or asp_led_init(). 680 ** KittyHawk machines have often a buggy PDC, so that 681 ** we explicitly check for those machines here. 682 */ 683 684 int __init led_init(void) 685 { 686 struct pdc_chassis_info chassis_info; 687 int ret; 688 689 snprintf(lcd_text_default, sizeof(lcd_text_default), 690 "Linux %s", init_utsname()->release); 691 692 /* Work around the buggy PDC of KittyHawk-machines */ 693 switch (CPU_HVERSION) { 694 case 0x580: /* KittyHawk DC2-100 (K100) */ 695 case 0x581: /* KittyHawk DC3-120 (K210) */ 696 case 0x582: /* KittyHawk DC3 100 (K400) */ 697 case 0x583: /* KittyHawk DC3 120 (K410) */ 698 case 0x58B: /* KittyHawk DC2 100 (K200) */ 699 printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, " 700 "LED detection skipped.\n", __FILE__, CPU_HVERSION); 701 lcd_no_led_support = 1; 702 goto found; /* use the preinitialized values of lcd_info */ 703 } 704 705 /* initialize the struct, so that we can check for valid return values */ 706 lcd_info.model = DISPLAY_MODEL_NONE; 707 chassis_info.actcnt = chassis_info.maxcnt = 0; 708 709 ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info)); 710 if (ret == PDC_OK) { 711 DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), " 712 "lcd_width=%d, cmd_delay=%u,\n" 713 "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n", 714 __FILE__, lcd_info.model, 715 (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" : 716 (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown", 717 lcd_info.lcd_width, lcd_info.min_cmd_delay, 718 __FILE__, sizeof(lcd_info), 719 chassis_info.actcnt, chassis_info.maxcnt)); 720 DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n", 721 __FILE__, lcd_info.lcd_cmd_reg_addr, 722 lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1, 723 lcd_info.reset_cmd2, lcd_info.act_enable )); 724 725 /* check the results. Some machines have a buggy PDC */ 726 if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt) 727 goto not_found; 728 729 switch (lcd_info.model) { 730 case DISPLAY_MODEL_LCD: /* LCD display */ 731 if (chassis_info.actcnt < 732 offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1) 733 goto not_found; 734 if (!lcd_info.act_enable) { 735 DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n")); 736 goto not_found; 737 } 738 break; 739 740 case DISPLAY_MODEL_NONE: /* no LED or LCD available */ 741 printk(KERN_INFO "PDC reported no LCD or LED.\n"); 742 goto not_found; 743 744 case DISPLAY_MODEL_LASI: /* Lasi style 8 bit LED display */ 745 if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32) 746 goto not_found; 747 break; 748 749 default: 750 printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n", 751 lcd_info.model); 752 goto not_found; 753 } /* switch() */ 754 755 found: 756 /* register the LCD/LED driver */ 757 register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG); 758 return 0; 759 760 } else { /* if() */ 761 DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret)); 762 } 763 764 not_found: 765 lcd_info.model = DISPLAY_MODEL_NONE; 766 return 1; 767 } 768 769 static void __exit led_exit(void) 770 { 771 unregister_reboot_notifier(&led_notifier); 772 return; 773 } 774 775 #ifdef CONFIG_PROC_FS 776 module_init(led_create_procfs) 777 #endif 778