led.c
上传用户:jlfgdled
上传日期:2013-04-10
资源大小:33168k
文件大小:20k
- /*
- * Chassis LCD/LED driver for HP-PARISC workstations
- *
- * (c) Copyright 2000 Red Hat Software
- * (c) Copyright 2000 Helge Deller <hdeller@redhat.com>
- * (c) Copyright 2001-2002 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
- */
- #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/bitops.h>
- #include <linux/version.h>
- #include <linux/delay.h>
- #include <linux/netdevice.h>
- #include <linux/interrupt.h>
- #include <linux/kernel_stat.h>
- #include <linux/reboot.h>
- #include <linux/proc_fs.h>
- #include <linux/ctype.h>
- #include <asm/io.h>
- #include <asm/gsc.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];
- #if 0
- #define DPRINTK(x) printk x
- #else
- #define DPRINTK(x)
- #endif
- #define CALC_ADD(val, comp, add)
- (val<=(comp/8) ? add/16 : val<=(comp/4) ? add/8 : val<=(comp/2) ? add/4 : add)
- 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) */
- char *lcd_cmd_reg_addr; /* ptr to LCD cmd-register & data ptr for LED */
- char *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 (0xfffffffff0190000UL) /* 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: (char *) KITTYHAWK_LCD_CMD,
- lcd_data_reg_addr:(char *) 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: %dn", led_heartbeat);
- out += sprintf(out, "Disk IO: %dn", led_diskio);
- out += sprintf(out, "LAN Rx/Tx: %dn", led_lanrxtx);
- break;
- case LED_HASLCD:
- out += sprintf(out, "%sn", 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];
- int d;
- if (!capable(CAP_SYS_ADMIN))
- return -EACCES;
- memset(lbuf, 0, count);
- copy_from_user(lbuf, buf, count);
- 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 == 0)
- {
- /* reset to default */
- lcd_print("Linux " UTS_RELEASE);
- }
- else
- {
- /* chop off trailing n.. if the user gives multiple
- * n then it's all their fault.. */
- if (*cur && cur[strlen(cur)-1] == 'n')
- cur[strlen(cur)-1] = 0;
- 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 indicatorsn");
- 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_stats()
- **
- ** calculate the TX- & RX-troughput on the network interfaces in
- ** the system for usage in the LED code
- **
- ** (analog to dev_get_info() from net/core/dev.c)
- **
- */
- static unsigned long led_net_rx_counter, led_net_tx_counter;
- static void led_get_net_stats(int addvalue)
- {
- static unsigned long rx_total_last, tx_total_last;
- unsigned long rx_total, tx_total;
- struct net_device *dev;
- struct net_device_stats *stats;
- rx_total = tx_total = 0;
-
- /* we are running as a tasklet, so locking dev_base
- * for reading should be OK */
- read_lock(&dev_base_lock);
- for (dev = dev_base; dev != NULL; dev = dev->next) {
- if (dev->get_stats) {
- stats = dev->get_stats(dev);
- rx_total += stats->rx_packets;
- tx_total += stats->tx_packets;
- }
- }
- read_unlock(&dev_base_lock);
- rx_total -= rx_total_last;
- tx_total -= tx_total_last;
-
- if (rx_total)
- led_net_rx_counter += CALC_ADD(rx_total, tx_total, addvalue);
- if (tx_total)
- led_net_tx_counter += CALC_ADD(tx_total, rx_total, addvalue);
-
- rx_total_last += rx_total;
- tx_total_last += tx_total;
- }
- /*
- **
- ** led_get_diskio_stats()
- **
- ** calculate the disk-io througput in the system
- ** (analog to linux/fs/proc/proc_misc.c)
- **
- */
- static unsigned long led_diskio_counter;
- static void led_get_diskio_stats(int addvalue)
- {
- static unsigned int diskio_total_last, diskio_max;
- int major, disk, total;
-
- total = 0;
- for (major = 0; major < DK_MAX_MAJOR; major++) {
- for (disk = 0; disk < DK_MAX_DISK; disk++)
- total += kstat.dk_drive[major][disk];
- }
- total -= diskio_total_last;
-
- if (total) {
- if (total >= diskio_max) {
- led_diskio_counter += addvalue;
- diskio_max = total; /* new maximum value found */
- } else
- led_diskio_counter += CALC_ADD(total, diskio_max, addvalue);
- }
-
- diskio_total_last += total;
- }
- /*
- ** 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
- */
- static unsigned char currentleds; /* stores current value of the LEDs */
- #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)
- static void led_tasklet_func(unsigned long unused)
- {
- static unsigned int count, count_HZ;
- static unsigned char lastleds;
- /* exit if not initialized */
- if (!led_func_ptr)
- return;
- /* increment the local counters */
- ++count;
- if (++count_HZ == HZ)
- count_HZ = 0;
- 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;
- }
- /* gather network and diskio statistics and flash LEDs respectively */
- if (led_lanrxtx)
- {
- if ((count & 31) == 0)
- led_get_net_stats(30);
- if (led_net_rx_counter) {
- led_net_rx_counter--;
- currentleds |= LED_LAN_RCV;
- }
- else
- currentleds &= ~LED_LAN_RCV;
- if (led_net_tx_counter) {
- led_net_tx_counter--;
- currentleds |= LED_LAN_TX;
- }
- else
- currentleds &= ~LED_LAN_TX;
- }
- if (led_diskio)
- {
- /* avoid to calculate diskio-stats at same irq as netio-stats ! */
- if ((count & 31) == 15)
- led_get_diskio_stats(30);
- if (led_diskio_counter) {
- led_diskio_counter--;
- currentleds |= LED_DISK_IO;
- }
- else
- currentleds &= ~LED_DISK_IO;
- }
- /* 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, char *cmd_reg, char *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) ? NULL : cmd_reg;
- switch (lcd_info.model) {
- case DISPLAY_MODEL_LCD:
- LCD_DATA_REG = data_reg;
- printk(KERN_INFO "LCD display at %p,%p registeredn",
- LCD_CMD_REG , LCD_DATA_REG);
- led_func_ptr = led_LCD_driver;
- lcd_print( "Linux " UTS_RELEASE );
- 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 %p registeredn", 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 %p registeredn",
- 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 */
- strncpy(lcd_text, str, sizeof(lcd_text)-1);
-
- /* 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;
- /* 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;
- if ((ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info))) == PDC_OK) {
- DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), "
- "lcd_width=%d, cmd_delay=%u,n"
- "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ldn",
- __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=%dn",
- __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 %dn",
- 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 = %dn", ret));
- }
- not_found:
- lcd_info.model = DISPLAY_MODEL_NONE;
- return 1;
- }
- #ifdef CONFIG_PROC_FS
- module_init(led_create_procfs)
- #endif