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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
54static int led_type = -1;
55static int led_heartbeat = 1;
56static int led_diskio = 1;
57static int led_lanrxtx = 1;
58static char lcd_text[32];
59static 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
68struct 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 */
77struct 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. */
100static struct pdc_chassis_lcd_info_ret_block
101lcd_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 */
120static void (*led_func_ptr) (unsigned char);
121
122#define LED_HASLCD 1
123#define LED_NOLCD 0
124#ifdef CONFIG_PROC_FS
125static 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
157static 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
212parse_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
218static 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 */
258static 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 */
278static 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 */
297static 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 */
346static __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 */
400static __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
436static 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) */
491DECLARE_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
502static int led_halt(struct notifier_block *, unsigned long, void *);
503
504static struct notifier_block led_notifier = {
505 .notifier_call = led_halt,
506};
507
508static 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
543int __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
606void __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 */
630int 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
674int __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
744found:
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
753not_found:
754 lcd_info.model = DISPLAY_MODEL_NONE;
755 return 1;
756}
757
758#ifdef CONFIG_PROC_FS
759module_init(led_create_procfs)
760#endif