xref: /linux/drivers/parisc/led.c (revision 54a8a2220c936a47840c9a3d74910c5a56fae2ed)
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 <linux/rcupdate.h>
41 #include <asm/io.h>
42 #include <asm/processor.h>
43 #include <asm/hardware.h>
44 #include <asm/param.h>		/* HZ */
45 #include <asm/led.h>
46 #include <asm/pdc.h>
47 #include <asm/uaccess.h>
48 
49 /* The control of the LEDs and LCDs on PARISC-machines have to be done
50    completely in software. The necessary calculations are done in a tasklet
51    which is scheduled at every timer interrupt and since the calculations
52    may consume relatively much CPU-time some of the calculations can be
53    turned off with the following variables (controlled via procfs) */
54 
55 static int led_type = -1;
56 static int led_heartbeat = 1;
57 static int led_diskio = 1;
58 static int led_lanrxtx = 1;
59 static char lcd_text[32];
60 static char lcd_text_default[32];
61 
62 #if 0
63 #define DPRINTK(x)	printk x
64 #else
65 #define DPRINTK(x)
66 #endif
67 
68 
69 struct lcd_block {
70 	unsigned char command;	/* stores the command byte      */
71 	unsigned char on;	/* value for turning LED on     */
72 	unsigned char off;	/* value for turning LED off    */
73 };
74 
75 /* Structure returned by PDC_RETURN_CHASSIS_INFO */
76 /* NOTE: we use unsigned long:16 two times, since the following member
77    lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */
78 struct pdc_chassis_lcd_info_ret_block {
79 	unsigned long model:16;		/* DISPLAY_MODEL_XXXX */
80 	unsigned long lcd_width:16;	/* width of the LCD in chars (DISPLAY_MODEL_LCD only) */
81 	unsigned long lcd_cmd_reg_addr;	/* ptr to LCD cmd-register & data ptr for LED */
82 	unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */
83 	unsigned int min_cmd_delay;	/* delay in uS after cmd-write (LCD only) */
84 	unsigned char reset_cmd1;	/* command #1 for writing LCD string (LCD only) */
85 	unsigned char reset_cmd2;	/* command #2 for writing LCD string (LCD only) */
86 	unsigned char act_enable;	/* 0 = no activity (LCD only) */
87 	struct lcd_block heartbeat;
88 	struct lcd_block disk_io;
89 	struct lcd_block lan_rcv;
90 	struct lcd_block lan_tx;
91 	char _pad;
92 };
93 
94 
95 /* LCD_CMD and LCD_DATA for KittyHawk machines */
96 #define KITTYHAWK_LCD_CMD  F_EXTEND(0xf0190000UL) /* 64bit-ready */
97 #define KITTYHAWK_LCD_DATA (KITTYHAWK_LCD_CMD+1)
98 
99 /* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's
100  * HP seems to have used Sharp/Hitachi HD44780 LCDs most of the time. */
101 static struct pdc_chassis_lcd_info_ret_block
102 lcd_info __attribute__((aligned(8))) =
103 {
104 	.model =		DISPLAY_MODEL_LCD,
105 	.lcd_width =		16,
106 	.lcd_cmd_reg_addr =	KITTYHAWK_LCD_CMD,
107 	.lcd_data_reg_addr =	KITTYHAWK_LCD_DATA,
108 	.min_cmd_delay =	40,
109 	.reset_cmd1 =		0x80,
110 	.reset_cmd2 =		0xc0,
111 };
112 
113 
114 /* direct access to some of the lcd_info variables */
115 #define LCD_CMD_REG	lcd_info.lcd_cmd_reg_addr
116 #define LCD_DATA_REG	lcd_info.lcd_data_reg_addr
117 #define LED_DATA_REG	lcd_info.lcd_cmd_reg_addr	/* LASI & ASP only */
118 
119 
120 /* ptr to LCD/LED-specific function */
121 static void (*led_func_ptr) (unsigned char);
122 
123 #define LED_HASLCD 1
124 #define LED_NOLCD  0
125 #ifdef CONFIG_PROC_FS
126 static int led_proc_read(char *page, char **start, off_t off, int count,
127 	int *eof, void *data)
128 {
129 	char *out = page;
130 	int len;
131 
132 	switch ((long)data)
133 	{
134 	case LED_NOLCD:
135 		out += sprintf(out, "Heartbeat: %d\n", led_heartbeat);
136 		out += sprintf(out, "Disk IO: %d\n", led_diskio);
137 		out += sprintf(out, "LAN Rx/Tx: %d\n", led_lanrxtx);
138 		break;
139 	case LED_HASLCD:
140 		out += sprintf(out, "%s\n", lcd_text);
141 		break;
142 	default:
143 		*eof = 1;
144 		return 0;
145 	}
146 
147 	len = out - page - off;
148 	if (len < count) {
149 		*eof = 1;
150 		if (len <= 0) return 0;
151 	} else {
152 		len = count;
153 	}
154 	*start = page + off;
155 	return len;
156 }
157 
158 static int led_proc_write(struct file *file, const char *buf,
159 	unsigned long count, void *data)
160 {
161 	char *cur, lbuf[count + 1];
162 	int d;
163 
164 	if (!capable(CAP_SYS_ADMIN))
165 		return -EACCES;
166 
167 	memset(lbuf, 0, count + 1);
168 
169 	if (copy_from_user(lbuf, buf, count))
170 		return -EFAULT;
171 
172 	cur = lbuf;
173 
174 	/* skip initial spaces */
175 	while (*cur && isspace(*cur))
176 	{
177 		cur++;
178 	}
179 
180 	switch ((long)data)
181 	{
182 	case LED_NOLCD:
183 		d = *cur++ - '0';
184 		if (d != 0 && d != 1) goto parse_error;
185 		led_heartbeat = d;
186 
187 		if (*cur++ != ' ') goto parse_error;
188 
189 		d = *cur++ - '0';
190 		if (d != 0 && d != 1) goto parse_error;
191 		led_diskio = d;
192 
193 		if (*cur++ != ' ') goto parse_error;
194 
195 		d = *cur++ - '0';
196 		if (d != 0 && d != 1) goto parse_error;
197 		led_lanrxtx = d;
198 
199 		break;
200 	case LED_HASLCD:
201 		if (*cur && cur[strlen(cur)-1] == '\n')
202 			cur[strlen(cur)-1] = 0;
203 		if (*cur == 0)
204 			cur = lcd_text_default;
205 		lcd_print(cur);
206 		break;
207 	default:
208 		return 0;
209 	}
210 
211 	return count;
212 
213 parse_error:
214 	if ((long)data == LED_NOLCD)
215 		printk(KERN_CRIT "Parse error: expect \"n n n\" (n == 0 or 1) for heartbeat,\ndisk io and lan tx/rx indicators\n");
216 	return -EINVAL;
217 }
218 
219 static int __init led_create_procfs(void)
220 {
221 	struct proc_dir_entry *proc_pdc_root = NULL;
222 	struct proc_dir_entry *ent;
223 
224 	if (led_type == -1) return -1;
225 
226 	proc_pdc_root = proc_mkdir("pdc", 0);
227 	if (!proc_pdc_root) return -1;
228 	proc_pdc_root->owner = THIS_MODULE;
229 	ent = create_proc_entry("led", S_IFREG|S_IRUGO|S_IWUSR, proc_pdc_root);
230 	if (!ent) return -1;
231 	ent->nlink = 1;
232 	ent->data = (void *)LED_NOLCD; /* LED */
233 	ent->read_proc = led_proc_read;
234 	ent->write_proc = led_proc_write;
235 	ent->owner = THIS_MODULE;
236 
237 	if (led_type == LED_HASLCD)
238 	{
239 		ent = create_proc_entry("lcd", S_IFREG|S_IRUGO|S_IWUSR, proc_pdc_root);
240 		if (!ent) return -1;
241 		ent->nlink = 1;
242 		ent->data = (void *)LED_HASLCD; /* LCD */
243 		ent->read_proc = led_proc_read;
244 		ent->write_proc = led_proc_write;
245 		ent->owner = THIS_MODULE;
246 	}
247 
248 	return 0;
249 }
250 #endif
251 
252 /*
253    **
254    ** led_ASP_driver()
255    **
256  */
257 #define	LED_DATA	0x01	/* data to shift (0:on 1:off) */
258 #define	LED_STROBE	0x02	/* strobe to clock data */
259 static void led_ASP_driver(unsigned char leds)
260 {
261 	int i;
262 
263 	leds = ~leds;
264 	for (i = 0; i < 8; i++) {
265 		unsigned char value;
266 		value = (leds & 0x80) >> 7;
267 		gsc_writeb( value,		 LED_DATA_REG );
268 		gsc_writeb( value | LED_STROBE,	 LED_DATA_REG );
269 		leds <<= 1;
270 	}
271 }
272 
273 
274 /*
275    **
276    ** led_LASI_driver()
277    **
278  */
279 static void led_LASI_driver(unsigned char leds)
280 {
281 	leds = ~leds;
282 	gsc_writeb( leds, LED_DATA_REG );
283 }
284 
285 
286 /*
287    **
288    ** led_LCD_driver()
289    **
290    ** The logic of the LCD driver is, that we write at every scheduled call
291    ** only to one of LCD_CMD_REG _or_ LCD_DATA_REG - registers.
292    ** That way we don't need to let this tasklet busywait for min_cmd_delay
293    ** milliseconds.
294    **
295    ** TODO: check the value of "min_cmd_delay" against the value of HZ.
296    **
297  */
298 static void led_LCD_driver(unsigned char leds)
299 {
300 	static int last_index;	/* 0:heartbeat, 1:disk, 2:lan_in, 3:lan_out */
301 	static int last_was_cmd;/* 0: CMD was written last, 1: DATA was last */
302 	struct lcd_block *block_ptr;
303 	int value;
304 
305 	switch (last_index) {
306 	    case 0:	block_ptr = &lcd_info.heartbeat;
307 			value = leds & LED_HEARTBEAT;
308 			break;
309 	    case 1:	block_ptr = &lcd_info.disk_io;
310 			value = leds & LED_DISK_IO;
311 			break;
312 	    case 2:	block_ptr = &lcd_info.lan_rcv;
313 			value = leds & LED_LAN_RCV;
314 			break;
315 	    case 3:	block_ptr = &lcd_info.lan_tx;
316 			value = leds & LED_LAN_TX;
317 			break;
318 	    default:	/* should never happen: */
319 			return;
320 	}
321 
322 	if (last_was_cmd) {
323 	    /* write the value to the LCD data port */
324     	    gsc_writeb( value ? block_ptr->on : block_ptr->off, LCD_DATA_REG );
325 	} else {
326 	    /* write the command-byte to the LCD command register */
327     	    gsc_writeb( block_ptr->command, LCD_CMD_REG );
328 	}
329 
330 	/* now update the vars for the next interrupt iteration */
331 	if (++last_was_cmd == 2) { /* switch between cmd & data */
332 	    last_was_cmd = 0;
333 	    if (++last_index == 4)
334 		last_index = 0;	 /* switch back to heartbeat index */
335 	}
336 }
337 
338 
339 /*
340    **
341    ** led_get_net_activity()
342    **
343    ** calculate if there was TX- or RX-troughput 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 unsigned long rx_total_last, tx_total_last;
353 	unsigned long 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 tasklet, so locking dev_base
360 	 * for reading should be OK */
361 	read_lock(&dev_base_lock);
362 	rcu_read_lock();
363 	for (dev = dev_base; dev; dev = dev->next) {
364 	    struct net_device_stats *stats;
365 	    struct in_device *in_dev = __in_dev_get_rcu(dev);
366 	    if (!in_dev || !in_dev->ifa_list)
367 		continue;
368 	    if (LOOPBACK(in_dev->ifa_list->ifa_local))
369 		continue;
370 	    if (!dev->get_stats)
371 		continue;
372 	    stats = dev->get_stats(dev);
373 	    rx_total += stats->rx_packets;
374 	    tx_total += stats->tx_packets;
375 	}
376 	rcu_read_unlock();
377 	read_unlock(&dev_base_lock);
378 
379 	retval = 0;
380 
381 	if (rx_total != rx_total_last) {
382 		rx_total_last = rx_total;
383 		retval |= LED_LAN_RCV;
384 	}
385 
386 	if (tx_total != tx_total_last) {
387 		tx_total_last = tx_total;
388 		retval |= LED_LAN_TX;
389 	}
390 
391 	return retval;
392 #endif
393 }
394 
395 
396 /*
397    **
398    ** led_get_diskio_activity()
399    **
400    ** calculate if there was disk-io in the system
401    **
402  */
403 static __inline__ int led_get_diskio_activity(void)
404 {
405 	static unsigned long last_pgpgin, last_pgpgout;
406 	struct page_state pgstat;
407 	int changed;
408 
409 	get_full_page_state(&pgstat); /* get no of sectors in & out */
410 
411 	/* Just use a very simple calculation here. Do not care about overflow,
412 	   since we only want to know if there was activity or not. */
413 	changed = (pgstat.pgpgin != last_pgpgin) || (pgstat.pgpgout != last_pgpgout);
414 	last_pgpgin  = pgstat.pgpgin;
415 	last_pgpgout = pgstat.pgpgout;
416 
417 	return (changed ? LED_DISK_IO : 0);
418 }
419 
420 
421 
422 /*
423    ** led_tasklet_func()
424    **
425    ** is scheduled at every timer interrupt from time.c and
426    ** updates the chassis LCD/LED
427 
428     TODO:
429     - display load average (older machines like 715/64 have 4 "free" LED's for that)
430     - optimizations
431  */
432 
433 #define HEARTBEAT_LEN (HZ*6/100)
434 #define HEARTBEAT_2ND_RANGE_START (HZ*22/100)
435 #define HEARTBEAT_2ND_RANGE_END   (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN)
436 
437 #define NORMALIZED_COUNT(count) (count/(HZ/100))
438 
439 static void led_tasklet_func(unsigned long unused)
440 {
441 	static unsigned char lastleds;
442 	unsigned char currentleds; /* stores current value of the LEDs */
443 	static unsigned long count; /* static incremented value, not wrapped */
444 	static unsigned long count_HZ; /* counter in range 0..HZ */
445 
446 	/* exit if not initialized */
447 	if (!led_func_ptr)
448 	    return;
449 
450 	/* increment the local counters */
451 	++count;
452 	if (++count_HZ == HZ)
453 	    count_HZ = 0;
454 
455 	currentleds = lastleds;
456 
457 	if (led_heartbeat)
458 	{
459 		/* flash heartbeat-LED like a real heart (2 x short then a long delay) */
460 		if (count_HZ<HEARTBEAT_LEN ||
461 		    (count_HZ>=HEARTBEAT_2ND_RANGE_START && count_HZ<HEARTBEAT_2ND_RANGE_END))
462 		    currentleds |= LED_HEARTBEAT;
463 		else
464 		    currentleds &= ~LED_HEARTBEAT;
465 	}
466 
467 	/* look for network activity and flash LEDs respectively */
468 	if (led_lanrxtx && ((NORMALIZED_COUNT(count)+(8/2)) & 7) == 0)
469 	{
470 		currentleds &= ~(LED_LAN_RCV | LED_LAN_TX);
471 		currentleds |= led_get_net_activity();
472 	}
473 
474 	/* avoid to calculate diskio-stats at same irq  as netio-stats */
475 	if (led_diskio && (NORMALIZED_COUNT(count) & 7) == 0)
476 	{
477 		currentleds &= ~LED_DISK_IO;
478 		currentleds |= led_get_diskio_activity();
479 	}
480 
481 	/* blink all LEDs twice a second if we got an Oops (HPMC) */
482 	if (oops_in_progress) {
483 		currentleds = (count_HZ<=(HZ/2)) ? 0 : 0xff;
484 	}
485 
486 	/* update the LCD/LEDs */
487 	if (currentleds != lastleds) {
488 	    led_func_ptr(currentleds);
489 	    lastleds = currentleds;
490 	}
491 }
492 
493 /* main led tasklet struct (scheduled from time.c) */
494 DECLARE_TASKLET_DISABLED(led_tasklet, led_tasklet_func, 0);
495 
496 
497 /*
498    ** led_halt()
499    **
500    ** called by the reboot notifier chain at shutdown and stops all
501    ** LED/LCD activities.
502    **
503  */
504 
505 static int led_halt(struct notifier_block *, unsigned long, void *);
506 
507 static struct notifier_block led_notifier = {
508 	.notifier_call = led_halt,
509 };
510 
511 static int led_halt(struct notifier_block *nb, unsigned long event, void *buf)
512 {
513 	char *txt;
514 
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 	/* completely stop the LED/LCD tasklet */
526 	tasklet_disable(&led_tasklet);
527 
528 	if (lcd_info.model == DISPLAY_MODEL_LCD)
529 		lcd_print(txt);
530 	else
531 		if (led_func_ptr)
532 			led_func_ptr(0xff); /* turn all LEDs ON */
533 
534 	unregister_reboot_notifier(&led_notifier);
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 		lcd_print( lcd_text_default );
563 		led_type = LED_HASLCD;
564 		break;
565 
566 	case DISPLAY_MODEL_LASI:
567 		LED_DATA_REG = data_reg;
568 		led_func_ptr = led_LASI_driver;
569 		printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG);
570 		led_type = LED_NOLCD;
571 		break;
572 
573 	case DISPLAY_MODEL_OLD_ASP:
574 		LED_DATA_REG = data_reg;
575 		led_func_ptr = led_ASP_driver;
576 		printk(KERN_INFO "LED (ASP-style) display at %lx registered\n",
577 		    LED_DATA_REG);
578 		led_type = LED_NOLCD;
579 		break;
580 
581 	default:
582 		printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n",
583 		       __FUNCTION__, lcd_info.model);
584 		return 1;
585 	}
586 
587 	/* mark the LCD/LED driver now as initialized and
588 	 * register to the reboot notifier chain */
589 	initialized++;
590 	register_reboot_notifier(&led_notifier);
591 
592 	/* start the led tasklet for the first time */
593 	tasklet_enable(&led_tasklet);
594 
595 	return 0;
596 }
597 
598 /*
599    ** register_led_regions()
600    **
601    ** register_led_regions() registers the LCD/LED regions for /procfs.
602    ** At bootup - where the initialisation of the LCD/LED normally happens -
603    ** not all internal structures of request_region() are properly set up,
604    ** so that we delay the led-registration until after busdevices_init()
605    ** has been executed.
606    **
607  */
608 
609 void __init register_led_regions(void)
610 {
611 	switch (lcd_info.model) {
612 	case DISPLAY_MODEL_LCD:
613 		request_mem_region((unsigned long)LCD_CMD_REG,  1, "lcd_cmd");
614 		request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data");
615 		break;
616 	case DISPLAY_MODEL_LASI:
617 	case DISPLAY_MODEL_OLD_ASP:
618 		request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data");
619 		break;
620 	}
621 }
622 
623 
624 /*
625    **
626    ** lcd_print()
627    **
628    ** Displays the given string on the LCD-Display of newer machines.
629    ** lcd_print() disables the timer-based led tasklet during its
630    ** execution and enables it afterwards again.
631    **
632  */
633 int lcd_print( char *str )
634 {
635 	int i;
636 
637 	if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD)
638 	    return 0;
639 
640 	/* temporarily disable the led tasklet */
641 	tasklet_disable(&led_tasklet);
642 
643 	/* copy display string to buffer for procfs */
644 	strlcpy(lcd_text, str, sizeof(lcd_text));
645 
646 	/* Set LCD Cursor to 1st character */
647 	gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG);
648 	udelay(lcd_info.min_cmd_delay);
649 
650 	/* Print the string */
651 	for (i=0; i < lcd_info.lcd_width; i++) {
652 	    if (str && *str)
653 		gsc_writeb(*str++, LCD_DATA_REG);
654 	    else
655 		gsc_writeb(' ', LCD_DATA_REG);
656 	    udelay(lcd_info.min_cmd_delay);
657 	}
658 
659 	/* re-enable the led tasklet */
660 	tasklet_enable(&led_tasklet);
661 
662 	return lcd_info.lcd_width;
663 }
664 
665 /*
666    ** led_init()
667    **
668    ** led_init() is called very early in the bootup-process from setup.c
669    ** and asks the PDC for an usable chassis LCD or LED.
670    ** If the PDC doesn't return any info, then the LED
671    ** is detected by lasi.c or asp.c and registered with the
672    ** above functions lasi_led_init() or asp_led_init().
673    ** KittyHawk machines have often a buggy PDC, so that
674    ** we explicitly check for those machines here.
675  */
676 
677 int __init led_init(void)
678 {
679 	struct pdc_chassis_info chassis_info;
680 	int ret;
681 
682 	snprintf(lcd_text_default, sizeof(lcd_text_default),
683 		"Linux %s", system_utsname.release);
684 
685 	/* Work around the buggy PDC of KittyHawk-machines */
686 	switch (CPU_HVERSION) {
687 	case 0x580:		/* KittyHawk DC2-100 (K100) */
688 	case 0x581:		/* KittyHawk DC3-120 (K210) */
689 	case 0x582:		/* KittyHawk DC3 100 (K400) */
690 	case 0x583:		/* KittyHawk DC3 120 (K410) */
691 	case 0x58B:		/* KittyHawk DC2 100 (K200) */
692 		printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "
693 				"LED detection skipped.\n", __FILE__, CPU_HVERSION);
694 		goto found;	/* use the preinitialized values of lcd_info */
695 	}
696 
697 	/* initialize the struct, so that we can check for valid return values */
698 	lcd_info.model = DISPLAY_MODEL_NONE;
699 	chassis_info.actcnt = chassis_info.maxcnt = 0;
700 
701 	ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info));
702 	if (ret == PDC_OK) {
703 		DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), "
704 			 "lcd_width=%d, cmd_delay=%u,\n"
705 			 "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n",
706 		         __FILE__, lcd_info.model,
707 			 (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" :
708 			  (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown",
709 			 lcd_info.lcd_width, lcd_info.min_cmd_delay,
710 			 __FILE__, sizeof(lcd_info),
711 			 chassis_info.actcnt, chassis_info.maxcnt));
712 		DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n",
713 			__FILE__, lcd_info.lcd_cmd_reg_addr,
714 			lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1,
715 			lcd_info.reset_cmd2, lcd_info.act_enable ));
716 
717 		/* check the results. Some machines have a buggy PDC */
718 		if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt)
719 			goto not_found;
720 
721 		switch (lcd_info.model) {
722 		case DISPLAY_MODEL_LCD:		/* LCD display */
723 			if (chassis_info.actcnt <
724 				offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)
725 				goto not_found;
726 			if (!lcd_info.act_enable) {
727 				DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n"));
728 				goto not_found;
729 			}
730 			break;
731 
732 		case DISPLAY_MODEL_NONE:	/* no LED or LCD available */
733 			printk(KERN_INFO "PDC reported no LCD or LED.\n");
734 			goto not_found;
735 
736 		case DISPLAY_MODEL_LASI:	/* Lasi style 8 bit LED display */
737 			if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32)
738 				goto not_found;
739 			break;
740 
741 		default:
742 			printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n",
743 			       lcd_info.model);
744 			goto not_found;
745 		} /* switch() */
746 
747 found:
748 		/* register the LCD/LED driver */
749 		register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG);
750 		return 0;
751 
752 	} else { /* if() */
753 		DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret));
754 	}
755 
756 not_found:
757 	lcd_info.model = DISPLAY_MODEL_NONE;
758 	return 1;
759 }
760 
761 #ifdef CONFIG_PROC_FS
762 module_init(led_create_procfs)
763 #endif
764