xref: /openbmc/linux/drivers/parisc/led.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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
761