Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 760 insertions, 0 deletions

diff --git a/drivers/parisc/led.c b/drivers/parisc/led.c
new file mode 100644
index 000000000000..e90fb72a6962
--- /dev/null
+++ b/drivers/parisc/led.c
@@ -0,0 +1,760 @@
+/*
+ *    Chassis LCD/LED driver for HP-PARISC workstations
+ *
+ *      (c) Copyright 2000 Red Hat Software
+ *      (c) Copyright 2000 Helge Deller <hdeller@redhat.com>
+ *      (c) Copyright 2001-2004 Helge Deller <deller@gmx.de>
+ *      (c) Copyright 2001 Randolph Chung <tausq@debian.org>
+ *
+ *      This program is free software; you can redistribute it and/or modify
+ *      it under the terms of the GNU General Public License as published by
+ *      the Free Software Foundation; either version 2 of the License, or
+ *      (at your option) any later version.
+ *
+ * TODO:
+ *	- speed-up calculations with inlined assembler
+ *	- interface to write to second row of LCD from /proc (if technically possible)
+ *
+ * Changes:
+ *      - Audit copy_from_user in led_proc_write.
+ *                                Daniele Bellucci <bellucda@tiscali.it>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/stddef.h>	/* for offsetof() */
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/ioport.h>
+#include <linux/utsname.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/in.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/reboot.h>
+#include <linux/proc_fs.h>
+#include <linux/ctype.h>
+#include <linux/blkdev.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/hardware.h>
+#include <asm/param.h>		/* HZ */
+#include <asm/led.h>
+#include <asm/pdc.h>
+#include <asm/uaccess.h>
+
+/* The control of the LEDs and LCDs on PARISC-machines have to be done 
+   completely in software. The necessary calculations are done in a tasklet
+   which is scheduled at every timer interrupt and since the calculations 
+   may consume relatively much CPU-time some of the calculations can be 
+   turned off with the following variables (controlled via procfs) */
+
+static int led_type = -1;
+static int led_heartbeat = 1;
+static int led_diskio = 1;
+static int led_lanrxtx = 1;
+static char lcd_text[32];
+static char lcd_text_default[32];
+
+#if 0
+#define DPRINTK(x)	printk x
+#else
+#define DPRINTK(x)
+#endif
+
+
+struct lcd_block {
+	unsigned char command;	/* stores the command byte      */
+	unsigned char on;	/* value for turning LED on     */
+	unsigned char off;	/* value for turning LED off    */
+};
+
+/* Structure returned by PDC_RETURN_CHASSIS_INFO */
+/* NOTE: we use unsigned long:16 two times, since the following member 
+   lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */
+struct pdc_chassis_lcd_info_ret_block {
+	unsigned long model:16;		/* DISPLAY_MODEL_XXXX */
+	unsigned long lcd_width:16;	/* width of the LCD in chars (DISPLAY_MODEL_LCD only) */
+	unsigned long lcd_cmd_reg_addr;	/* ptr to LCD cmd-register & data ptr for LED */
+	unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */
+	unsigned int min_cmd_delay;	/* delay in uS after cmd-write (LCD only) */
+	unsigned char reset_cmd1;	/* command #1 for writing LCD string (LCD only) */
+	unsigned char reset_cmd2;	/* command #2 for writing LCD string (LCD only) */
+	unsigned char act_enable;	/* 0 = no activity (LCD only) */
+	struct lcd_block heartbeat;
+	struct lcd_block disk_io;
+	struct lcd_block lan_rcv;
+	struct lcd_block lan_tx;
+	char _pad;
+};
+
+
+/* LCD_CMD and LCD_DATA for KittyHawk machines */
+#define KITTYHAWK_LCD_CMD  F_EXTEND(0xf0190000UL) /* 64bit-ready */
+#define KITTYHAWK_LCD_DATA (KITTYHAWK_LCD_CMD+1)
+
+/* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's 
+ * HP seems to have used Sharp/Hitachi HD44780 LCDs most of the time. */
+static struct pdc_chassis_lcd_info_ret_block
+lcd_info __attribute__((aligned(8))) =
+{
+	.model =		DISPLAY_MODEL_LCD,
+	.lcd_width =		16,
+	.lcd_cmd_reg_addr =	KITTYHAWK_LCD_CMD,
+	.lcd_data_reg_addr =	KITTYHAWK_LCD_DATA,
+	.min_cmd_delay =	40,
+	.reset_cmd1 =		0x80,
+	.reset_cmd2 =		0xc0,
+};
+
+
+/* direct access to some of the lcd_info variables */
+#define LCD_CMD_REG	lcd_info.lcd_cmd_reg_addr	 
+#define LCD_DATA_REG	lcd_info.lcd_data_reg_addr	 
+#define LED_DATA_REG	lcd_info.lcd_cmd_reg_addr	/* LASI & ASP only */
+
+
+/* ptr to LCD/LED-specific function */
+static void (*led_func_ptr) (unsigned char);
+
+#define LED_HASLCD 1
+#define LED_NOLCD  0
+#ifdef CONFIG_PROC_FS
+static int led_proc_read(char *page, char **start, off_t off, int count, 
+	int *eof, void *data)
+{
+	char *out = page;
+	int len;
+
+	switch ((long)data)
+	{
+	case LED_NOLCD:
+		out += sprintf(out, "Heartbeat: %d\n", led_heartbeat);
+		out += sprintf(out, "Disk IO: %d\n", led_diskio);
+		out += sprintf(out, "LAN Rx/Tx: %d\n", led_lanrxtx);
+		break;
+	case LED_HASLCD:
+		out += sprintf(out, "%s\n", lcd_text);
+		break;
+	default:
+		*eof = 1;
+		return 0;
+	}
+
+	len = out - page - off;
+	if (len < count) {
+		*eof = 1;
+		if (len <= 0) return 0;
+	} else {
+		len = count;
+	}
+	*start = page + off;
+	return len;
+}
+
+static int led_proc_write(struct file *file, const char *buf, 
+	unsigned long count, void *data)
+{
+	char *cur, lbuf[count + 1];
+	int d;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
+	memset(lbuf, 0, count + 1);
+
+	if (copy_from_user(lbuf, buf, count))
+		return -EFAULT;
+
+	cur = lbuf;
+
+	/* skip initial spaces */
+	while (*cur && isspace(*cur))
+	{
+		cur++;
+	}
+
+	switch ((long)data)
+	{
+	case LED_NOLCD:
+		d = *cur++ - '0';
+		if (d != 0 && d != 1) goto parse_error;
+		led_heartbeat = d;
+
+		if (*cur++ != ' ') goto parse_error;
+
+		d = *cur++ - '0';
+		if (d != 0 && d != 1) goto parse_error;
+		led_diskio = d;
+
+		if (*cur++ != ' ') goto parse_error;
+
+		d = *cur++ - '0';
+		if (d != 0 && d != 1) goto parse_error;
+		led_lanrxtx = d;
+
+		break;
+	case LED_HASLCD:
+		if (*cur && cur[strlen(cur)-1] == '\n')
+			cur[strlen(cur)-1] = 0;
+		if (*cur == 0) 
+			cur = lcd_text_default;
+		lcd_print(cur);
+		break;
+	default:
+		return 0;
+	}
+	
+	return count;
+
+parse_error:
+	if ((long)data == LED_NOLCD)
+		printk(KERN_CRIT "Parse error: expect \"n n n\" (n == 0 or 1) for heartbeat,\ndisk io and lan tx/rx indicators\n");
+	return -EINVAL;
+}
+
+static int __init led_create_procfs(void)
+{
+	struct proc_dir_entry *proc_pdc_root = NULL;
+	struct proc_dir_entry *ent;
+
+	if (led_type == -1) return -1;
+
+	proc_pdc_root = proc_mkdir("pdc", 0);
+	if (!proc_pdc_root) return -1;
+	proc_pdc_root->owner = THIS_MODULE;
+	ent = create_proc_entry("led", S_IFREG|S_IRUGO|S_IWUSR, proc_pdc_root);
+	if (!ent) return -1;
+	ent->nlink = 1;
+	ent->data = (void *)LED_NOLCD; /* LED */
+	ent->read_proc = led_proc_read;
+	ent->write_proc = led_proc_write;
+	ent->owner = THIS_MODULE;
+
+	if (led_type == LED_HASLCD)
+	{
+		ent = create_proc_entry("lcd", S_IFREG|S_IRUGO|S_IWUSR, proc_pdc_root);
+		if (!ent) return -1;
+		ent->nlink = 1;
+		ent->data = (void *)LED_HASLCD; /* LCD */
+		ent->read_proc = led_proc_read;
+		ent->write_proc = led_proc_write;
+		ent->owner = THIS_MODULE;
+	}
+
+	return 0;
+}
+#endif
+
+/*
+   ** 
+   ** led_ASP_driver()
+   ** 
+ */
+#define	LED_DATA	0x01	/* data to shift (0:on 1:off) */
+#define	LED_STROBE	0x02	/* strobe to clock data */
+static void led_ASP_driver(unsigned char leds)
+{
+	int i;
+
+	leds = ~leds;
+	for (i = 0; i < 8; i++) {
+		unsigned char value;
+		value = (leds & 0x80) >> 7;
+		gsc_writeb( value,		 LED_DATA_REG );
+		gsc_writeb( value | LED_STROBE,	 LED_DATA_REG );
+		leds <<= 1;
+	}
+}
+
+
+/*
+   ** 
+   ** led_LASI_driver()
+   ** 
+ */
+static void led_LASI_driver(unsigned char leds)
+{
+	leds = ~leds;
+	gsc_writeb( leds, LED_DATA_REG );
+}
+
+
+/*
+   ** 
+   ** led_LCD_driver()
+   ** 
+   ** The logic of the LCD driver is, that we write at every scheduled call
+   ** only to one of LCD_CMD_REG _or_ LCD_DATA_REG - registers.
+   ** That way we don't need to let this tasklet busywait for min_cmd_delay
+   ** milliseconds.
+   **
+   ** TODO: check the value of "min_cmd_delay" against the value of HZ.
+   **   
+ */
+static void led_LCD_driver(unsigned char leds)
+{
+	static int last_index;	/* 0:heartbeat, 1:disk, 2:lan_in, 3:lan_out */
+	static int last_was_cmd;/* 0: CMD was written last, 1: DATA was last */
+	struct lcd_block *block_ptr;
+	int value;
+
+	switch (last_index) {
+	    case 0:	block_ptr = &lcd_info.heartbeat;
+			value = leds & LED_HEARTBEAT;
+			break;
+	    case 1:	block_ptr = &lcd_info.disk_io;
+			value = leds & LED_DISK_IO;
+			break;					
+	    case 2:	block_ptr = &lcd_info.lan_rcv;
+			value = leds & LED_LAN_RCV;
+			break;					
+	    case 3:	block_ptr = &lcd_info.lan_tx;
+			value = leds & LED_LAN_TX;
+			break;
+	    default:	/* should never happen: */
+			return;
+	}
+
+	if (last_was_cmd) {
+	    /* write the value to the LCD data port */
+    	    gsc_writeb( value ? block_ptr->on : block_ptr->off, LCD_DATA_REG );
+	} else {
+	    /* write the command-byte to the LCD command register */
+    	    gsc_writeb( block_ptr->command, LCD_CMD_REG );
+	}    
+	
+	/* now update the vars for the next interrupt iteration */ 
+	if (++last_was_cmd == 2) { /* switch between cmd & data */
+	    last_was_cmd = 0;
+	    if (++last_index == 4) 
+		last_index = 0;	 /* switch back to heartbeat index */
+	}
+}
+
+
+/*
+   ** 
+   ** led_get_net_activity()
+   ** 
+   ** calculate if there was TX- or RX-troughput on the network interfaces
+   ** (analog to dev_get_info() from net/core/dev.c)
+   **   
+ */
+static __inline__ int led_get_net_activity(void)
+{ 
+#ifndef CONFIG_NET
+	return 0;
+#else
+	static unsigned long rx_total_last, tx_total_last;
+	unsigned long rx_total, tx_total;
+	struct net_device *dev;
+	int retval;
+
+	rx_total = tx_total = 0;
+	
+	/* we are running as tasklet, so locking dev_base 
+	 * for reading should be OK */
+	read_lock(&dev_base_lock);
+	for (dev = dev_base; dev; dev = dev->next) {
+	    struct net_device_stats *stats;
+	    struct in_device *in_dev = __in_dev_get(dev);
+	    if (!in_dev || !in_dev->ifa_list)
+		continue;
+	    if (LOOPBACK(in_dev->ifa_list->ifa_local))
+		continue;
+	    if (!dev->get_stats) 
+		continue;
+	    stats = dev->get_stats(dev);
+	    rx_total += stats->rx_packets;
+	    tx_total += stats->tx_packets;
+	}
+	read_unlock(&dev_base_lock);
+
+	retval = 0;
+
+	if (rx_total != rx_total_last) {
+		rx_total_last = rx_total;
+		retval |= LED_LAN_RCV;
+	}
+
+	if (tx_total != tx_total_last) {
+		tx_total_last = tx_total;
+		retval |= LED_LAN_TX;
+	}
+
+	return retval;
+#endif
+}
+
+
+/*
+   ** 
+   ** led_get_diskio_activity()
+   ** 
+   ** calculate if there was disk-io in the system
+   **   
+ */
+static __inline__ int led_get_diskio_activity(void)
+{	
+	static unsigned long last_pgpgin, last_pgpgout;
+	struct page_state pgstat;
+	int changed;
+	
+	get_full_page_state(&pgstat); /* get no of sectors in & out */
+
+	/* Just use a very simple calculation here. Do not care about overflow,
+	   since we only want to know if there was activity or not. */
+	changed = (pgstat.pgpgin != last_pgpgin) || (pgstat.pgpgout != last_pgpgout);
+	last_pgpgin  = pgstat.pgpgin;
+	last_pgpgout = pgstat.pgpgout;
+	
+	return (changed ? LED_DISK_IO : 0);
+}
+
+
+
+/*
+   ** led_tasklet_func()
+   ** 
+   ** is scheduled at every timer interrupt from time.c and
+   ** updates the chassis LCD/LED 
+
+    TODO:
+    - display load average (older machines like 715/64 have 4 "free" LED's for that)
+    - optimizations
+ */
+
+#define HEARTBEAT_LEN (HZ*6/100)
+#define HEARTBEAT_2ND_RANGE_START (HZ*22/100)
+#define HEARTBEAT_2ND_RANGE_END   (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN)
+
+#define NORMALIZED_COUNT(count) (count/(HZ/100))
+
+static void led_tasklet_func(unsigned long unused)
+{
+	static unsigned char lastleds;
+	unsigned char currentleds; /* stores current value of the LEDs */
+	static unsigned long count; /* static incremented value, not wrapped */
+	static unsigned long count_HZ; /* counter in range 0..HZ */
+
+	/* exit if not initialized */
+	if (!led_func_ptr)
+	    return;
+
+	/* increment the local counters */
+	++count;
+	if (++count_HZ == HZ)
+	    count_HZ = 0;
+
+	currentleds = lastleds;
+
+	if (led_heartbeat)
+	{
+		/* flash heartbeat-LED like a real heart (2 x short then a long delay) */
+		if (count_HZ<HEARTBEAT_LEN || 
+		    (count_HZ>=HEARTBEAT_2ND_RANGE_START && count_HZ<HEARTBEAT_2ND_RANGE_END)) 
+		    currentleds |= LED_HEARTBEAT;
+		else
+		    currentleds &= ~LED_HEARTBEAT;
+	}
+
+	/* look for network activity and flash LEDs respectively */
+	if (led_lanrxtx && ((NORMALIZED_COUNT(count)+(8/2)) & 7) == 0)
+	{
+		currentleds &= ~(LED_LAN_RCV | LED_LAN_TX);
+		currentleds |= led_get_net_activity();
+	}
+
+	/* avoid to calculate diskio-stats at same irq  as netio-stats */
+	if (led_diskio && (NORMALIZED_COUNT(count) & 7) == 0)
+	{
+		currentleds &= ~LED_DISK_IO;
+		currentleds |= led_get_diskio_activity();
+	}
+
+	/* blink all LEDs twice a second if we got an Oops (HPMC) */
+	if (oops_in_progress) {
+		currentleds = (count_HZ<=(HZ/2)) ? 0 : 0xff;
+	}
+	
+	/* update the LCD/LEDs */
+	if (currentleds != lastleds) {
+	    led_func_ptr(currentleds);
+	    lastleds = currentleds;
+	}
+}
+
+/* main led tasklet struct (scheduled from time.c) */
+DECLARE_TASKLET_DISABLED(led_tasklet, led_tasklet_func, 0);
+
+
+/*
+   ** led_halt()
+   ** 
+   ** called by the reboot notifier chain at shutdown and stops all
+   ** LED/LCD activities.
+   ** 
+ */
+
+static int led_halt(struct notifier_block *, unsigned long, void *);
+
+static struct notifier_block led_notifier = {
+	.notifier_call = led_halt,
+};
+
+static int led_halt(struct notifier_block *nb, unsigned long event, void *buf) 
+{
+	char *txt;
+	
+	switch (event) {
+	case SYS_RESTART:	txt = "SYSTEM RESTART";
+				break;
+	case SYS_HALT:		txt = "SYSTEM HALT";
+				break;
+	case SYS_POWER_OFF:	txt = "SYSTEM POWER OFF";
+				break;
+	default:		return NOTIFY_DONE;
+	}
+	
+	/* completely stop the LED/LCD tasklet */
+	tasklet_disable(&led_tasklet);
+
+	if (lcd_info.model == DISPLAY_MODEL_LCD)
+		lcd_print(txt);
+	else
+		if (led_func_ptr)
+			led_func_ptr(0xff); /* turn all LEDs ON */
+	
+	unregister_reboot_notifier(&led_notifier);
+	return NOTIFY_OK;
+}
+
+/*
+   ** register_led_driver()
+   ** 
+   ** registers an external LED or LCD for usage by this driver.
+   ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported.
+   ** 
+ */
+
+int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg)
+{
+	static int initialized;
+	
+	if (initialized || !data_reg)
+		return 1;
+	
+	lcd_info.model = model;		/* store the values */
+	LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg;
+
+	switch (lcd_info.model) {
+	case DISPLAY_MODEL_LCD:
+		LCD_DATA_REG = data_reg;
+		printk(KERN_INFO "LCD display at %lx,%lx registered\n", 
+			LCD_CMD_REG , LCD_DATA_REG);
+		led_func_ptr = led_LCD_driver;
+		lcd_print( lcd_text_default );
+		led_type = LED_HASLCD;
+		break;
+
+	case DISPLAY_MODEL_LASI:
+		LED_DATA_REG = data_reg;
+		led_func_ptr = led_LASI_driver;
+		printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG);
+		led_type = LED_NOLCD;
+		break;
+
+	case DISPLAY_MODEL_OLD_ASP:
+		LED_DATA_REG = data_reg;
+		led_func_ptr = led_ASP_driver;
+		printk(KERN_INFO "LED (ASP-style) display at %lx registered\n", 
+		    LED_DATA_REG);
+		led_type = LED_NOLCD;
+		break;
+
+	default:
+		printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n",
+		       __FUNCTION__, lcd_info.model);
+		return 1;
+	}
+	
+	/* mark the LCD/LED driver now as initialized and 
+	 * register to the reboot notifier chain */
+	initialized++;
+	register_reboot_notifier(&led_notifier);
+
+	/* start the led tasklet for the first time */
+	tasklet_enable(&led_tasklet);
+	
+	return 0;
+}
+
+/*
+   ** register_led_regions()
+   ** 
+   ** register_led_regions() registers the LCD/LED regions for /procfs.
+   ** At bootup - where the initialisation of the LCD/LED normally happens - 
+   ** not all internal structures of request_region() are properly set up,
+   ** so that we delay the led-registration until after busdevices_init() 
+   ** has been executed.
+   **
+ */
+
+void __init register_led_regions(void)
+{
+	switch (lcd_info.model) {
+	case DISPLAY_MODEL_LCD:
+		request_mem_region((unsigned long)LCD_CMD_REG,  1, "lcd_cmd");
+		request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data");
+		break;
+	case DISPLAY_MODEL_LASI:
+	case DISPLAY_MODEL_OLD_ASP:
+		request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data");
+		break;
+	}
+}
+
+
+/*
+   ** 
+   ** lcd_print()
+   ** 
+   ** Displays the given string on the LCD-Display of newer machines.
+   ** lcd_print() disables the timer-based led tasklet during its 
+   ** execution and enables it afterwards again.
+   **
+ */
+int lcd_print( char *str )
+{
+	int i;
+
+	if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD)
+	    return 0;
+	
+	/* temporarily disable the led tasklet */
+	tasklet_disable(&led_tasklet);
+
+	/* copy display string to buffer for procfs */
+	strlcpy(lcd_text, str, sizeof(lcd_text));
+	
+	/* Set LCD Cursor to 1st character */
+	gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG);
+	udelay(lcd_info.min_cmd_delay);
+
+	/* Print the string */
+	for (i=0; i < lcd_info.lcd_width; i++) {
+	    if (str && *str)
+		gsc_writeb(*str++, LCD_DATA_REG);
+	    else
+		gsc_writeb(' ', LCD_DATA_REG);
+	    udelay(lcd_info.min_cmd_delay);
+	}
+	
+	/* re-enable the led tasklet */
+	tasklet_enable(&led_tasklet);
+
+	return lcd_info.lcd_width;
+}
+
+/*
+   ** led_init()
+   ** 
+   ** led_init() is called very early in the bootup-process from setup.c 
+   ** and asks the PDC for an usable chassis LCD or LED.
+   ** If the PDC doesn't return any info, then the LED
+   ** is detected by lasi.c or asp.c and registered with the
+   ** above functions lasi_led_init() or asp_led_init().
+   ** KittyHawk machines have often a buggy PDC, so that
+   ** we explicitly check for those machines here.
+ */
+
+int __init led_init(void)
+{
+	struct pdc_chassis_info chassis_info;
+	int ret;
+
+	snprintf(lcd_text_default, sizeof(lcd_text_default),
+		"Linux %s", system_utsname.release);
+
+	/* Work around the buggy PDC of KittyHawk-machines */
+	switch (CPU_HVERSION) {
+	case 0x580:		/* KittyHawk DC2-100 (K100) */
+	case 0x581:		/* KittyHawk DC3-120 (K210) */
+	case 0x582:		/* KittyHawk DC3 100 (K400) */
+	case 0x583:		/* KittyHawk DC3 120 (K410) */
+	case 0x58B:		/* KittyHawk DC2 100 (K200) */
+		printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "
+				"LED detection skipped.\n", __FILE__, CPU_HVERSION);
+		goto found;	/* use the preinitialized values of lcd_info */
+	}
+
+	/* initialize the struct, so that we can check for valid return values */
+	lcd_info.model = DISPLAY_MODEL_NONE;
+	chassis_info.actcnt = chassis_info.maxcnt = 0;
+
+	ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info));
+	if (ret == PDC_OK) {
+		DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), "
+			 "lcd_width=%d, cmd_delay=%u,\n"
+			 "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n",
+		         __FILE__, lcd_info.model,
+			 (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" :
+			  (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown",
+			 lcd_info.lcd_width, lcd_info.min_cmd_delay,
+			 __FILE__, sizeof(lcd_info), 
+			 chassis_info.actcnt, chassis_info.maxcnt));
+		DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n",
+			__FILE__, lcd_info.lcd_cmd_reg_addr, 
+			lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1,  
+			lcd_info.reset_cmd2, lcd_info.act_enable ));
+	
+		/* check the results. Some machines have a buggy PDC */
+		if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt)
+			goto not_found;
+
+		switch (lcd_info.model) {
+		case DISPLAY_MODEL_LCD:		/* LCD display */
+			if (chassis_info.actcnt < 
+				offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)
+				goto not_found;
+			if (!lcd_info.act_enable) {
+				DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n"));
+				goto not_found;
+			}
+			break;
+
+		case DISPLAY_MODEL_NONE:	/* no LED or LCD available */
+			printk(KERN_INFO "PDC reported no LCD or LED.\n");
+			goto not_found;
+
+		case DISPLAY_MODEL_LASI:	/* Lasi style 8 bit LED display */
+			if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32)
+				goto not_found;
+			break;
+
+		default:
+			printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n",
+			       lcd_info.model);
+			goto not_found;
+		} /* switch() */
+
+found:
+		/* register the LCD/LED driver */
+		register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG);
+		return 0;
+
+	} else { /* if() */
+		DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret));
+	}
+
+not_found:
+	lcd_info.model = DISPLAY_MODEL_NONE;
+	return 1;
+}
+
+#ifdef CONFIG_PROC_FS
+module_init(led_create_procfs)
+#endif