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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/parisc/led.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2v2.6.12-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!
Diffstat (limited to 'drivers/parisc/led.c')
-rw-r--r--drivers/parisc/led.c760
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