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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 2001-2009 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 * - Switch from using a tasklet to a work queue, so the led_LCD_driver
22 * can sleep.
23 * David Pye <dmp@davidmpye.dyndns.org>
24 */
25
26#include <linux/module.h>
27#include <linux/stddef.h> /* for offsetof() */
28#include <linux/init.h>
29#include <linux/types.h>
30#include <linux/ioport.h>
31#include <linux/utsname.h>
32#include <linux/capability.h>
33#include <linux/delay.h>
34#include <linux/netdevice.h>
35#include <linux/inetdevice.h>
36#include <linux/in.h>
37#include <linux/interrupt.h>
38#include <linux/kernel_stat.h>
39#include <linux/reboot.h>
40#include <linux/proc_fs.h>
41#include <linux/seq_file.h>
42#include <linux/ctype.h>
43#include <linux/blkdev.h>
44#include <linux/workqueue.h>
45#include <linux/rcupdate.h>
46#include <asm/io.h>
47#include <asm/processor.h>
48#include <asm/hardware.h>
49#include <asm/param.h> /* HZ */
50#include <asm/led.h>
51#include <asm/pdc.h>
52#include <asm/uaccess.h>
53
54/* The control of the LEDs and LCDs on PARISC-machines have to be done
55 completely in software. The necessary calculations are done in a work queue
56 task which is scheduled regularly, and since the calculations may consume a
57 relatively large amount of CPU time, some of the calculations can be
58 turned off with the following variables (controlled via procfs) */
59
60static int led_type __read_mostly = -1;
61static unsigned char lastleds; /* LED state from most recent update */
62static unsigned int led_heartbeat __read_mostly = 1;
63static unsigned int led_diskio __read_mostly = 1;
64static unsigned int led_lanrxtx __read_mostly = 1;
65static char lcd_text[32] __read_mostly;
66static char lcd_text_default[32] __read_mostly;
67static int lcd_no_led_support __read_mostly = 0; /* KittyHawk doesn't support LED on its LCD */
68
69
70static struct workqueue_struct *led_wq;
71static void led_work_func(struct work_struct *);
72static DECLARE_DELAYED_WORK(led_task, led_work_func);
73
74#if 0
75#define DPRINTK(x) printk x
76#else
77#define DPRINTK(x)
78#endif
79
80struct lcd_block {
81 unsigned char command; /* stores the command byte */
82 unsigned char on; /* value for turning LED on */
83 unsigned char off; /* value for turning LED off */
84};
85
86/* Structure returned by PDC_RETURN_CHASSIS_INFO */
87/* NOTE: we use unsigned long:16 two times, since the following member
88 lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */
89struct pdc_chassis_lcd_info_ret_block {
90 unsigned long model:16; /* DISPLAY_MODEL_XXXX */
91 unsigned long lcd_width:16; /* width of the LCD in chars (DISPLAY_MODEL_LCD only) */
92 unsigned long lcd_cmd_reg_addr; /* ptr to LCD cmd-register & data ptr for LED */
93 unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */
94 unsigned int min_cmd_delay; /* delay in uS after cmd-write (LCD only) */
95 unsigned char reset_cmd1; /* command #1 for writing LCD string (LCD only) */
96 unsigned char reset_cmd2; /* command #2 for writing LCD string (LCD only) */
97 unsigned char act_enable; /* 0 = no activity (LCD only) */
98 struct lcd_block heartbeat;
99 struct lcd_block disk_io;
100 struct lcd_block lan_rcv;
101 struct lcd_block lan_tx;
102 char _pad;
103};
104
105
106/* LCD_CMD and LCD_DATA for KittyHawk machines */
107#define KITTYHAWK_LCD_CMD F_EXTEND(0xf0190000UL) /* 64bit-ready */
108#define KITTYHAWK_LCD_DATA (KITTYHAWK_LCD_CMD+1)
109
110/* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's
111 * HP seems to have used Sharp/Hitachi HD44780 LCDs most of the time. */
112static struct pdc_chassis_lcd_info_ret_block
113lcd_info __attribute__((aligned(8))) __read_mostly =
114{
115 .model = DISPLAY_MODEL_LCD,
116 .lcd_width = 16,
117 .lcd_cmd_reg_addr = KITTYHAWK_LCD_CMD,
118 .lcd_data_reg_addr = KITTYHAWK_LCD_DATA,
119 .min_cmd_delay = 80,
120 .reset_cmd1 = 0x80,
121 .reset_cmd2 = 0xc0,
122};
123
124
125/* direct access to some of the lcd_info variables */
126#define LCD_CMD_REG lcd_info.lcd_cmd_reg_addr
127#define LCD_DATA_REG lcd_info.lcd_data_reg_addr
128#define LED_DATA_REG lcd_info.lcd_cmd_reg_addr /* LASI & ASP only */
129
130#define LED_HASLCD 1
131#define LED_NOLCD 0
132
133/* The workqueue must be created at init-time */
134static int start_task(void)
135{
136 /* Display the default text now */
137 if (led_type == LED_HASLCD) lcd_print( lcd_text_default );
138
139 /* KittyHawk has no LED support on its LCD */
140 if (lcd_no_led_support) return 0;
141
142 /* Create the work queue and queue the LED task */
143 led_wq = create_singlethread_workqueue("led_wq");
144 queue_delayed_work(led_wq, &led_task, 0);
145
146 return 0;
147}
148
149device_initcall(start_task);
150
151/* ptr to LCD/LED-specific function */
152static void (*led_func_ptr) (unsigned char) __read_mostly;
153
154#ifdef CONFIG_PROC_FS
155static int led_proc_show(struct seq_file *m, void *v)
156{
157 switch ((long)m->private)
158 {
159 case LED_NOLCD:
160 seq_printf(m, "Heartbeat: %d\n", led_heartbeat);
161 seq_printf(m, "Disk IO: %d\n", led_diskio);
162 seq_printf(m, "LAN Rx/Tx: %d\n", led_lanrxtx);
163 break;
164 case LED_HASLCD:
165 seq_printf(m, "%s\n", lcd_text);
166 break;
167 default:
168 return 0;
169 }
170 return 0;
171}
172
173static int led_proc_open(struct inode *inode, struct file *file)
174{
175 return single_open(file, led_proc_show, PDE_DATA(inode));
176}
177
178
179static ssize_t led_proc_write(struct file *file, const char *buf,
180 size_t count, loff_t *pos)
181{
182 void *data = PDE_DATA(file_inode(file));
183 char *cur, lbuf[32];
184 int d;
185
186 if (!capable(CAP_SYS_ADMIN))
187 return -EACCES;
188
189 if (count >= sizeof(lbuf))
190 count = sizeof(lbuf)-1;
191
192 if (copy_from_user(lbuf, buf, count))
193 return -EFAULT;
194 lbuf[count] = 0;
195
196 cur = lbuf;
197
198 switch ((long)data)
199 {
200 case LED_NOLCD:
201 d = *cur++ - '0';
202 if (d != 0 && d != 1) goto parse_error;
203 led_heartbeat = d;
204
205 if (*cur++ != ' ') goto parse_error;
206
207 d = *cur++ - '0';
208 if (d != 0 && d != 1) goto parse_error;
209 led_diskio = d;
210
211 if (*cur++ != ' ') goto parse_error;
212
213 d = *cur++ - '0';
214 if (d != 0 && d != 1) goto parse_error;
215 led_lanrxtx = d;
216
217 break;
218 case LED_HASLCD:
219 if (*cur && cur[strlen(cur)-1] == '\n')
220 cur[strlen(cur)-1] = 0;
221 if (*cur == 0)
222 cur = lcd_text_default;
223 lcd_print(cur);
224 break;
225 default:
226 return 0;
227 }
228
229 return count;
230
231parse_error:
232 if ((long)data == LED_NOLCD)
233 printk(KERN_CRIT "Parse error: expect \"n n n\" (n == 0 or 1) for heartbeat,\ndisk io and lan tx/rx indicators\n");
234 return -EINVAL;
235}
236
237static const struct file_operations led_proc_fops = {
238 .owner = THIS_MODULE,
239 .open = led_proc_open,
240 .read = seq_read,
241 .llseek = seq_lseek,
242 .release = single_release,
243 .write = led_proc_write,
244};
245
246static int __init led_create_procfs(void)
247{
248 struct proc_dir_entry *proc_pdc_root = NULL;
249 struct proc_dir_entry *ent;
250
251 if (led_type == -1) return -1;
252
253 proc_pdc_root = proc_mkdir("pdc", 0);
254 if (!proc_pdc_root) return -1;
255
256 if (!lcd_no_led_support)
257 {
258 ent = proc_create_data("led", S_IRUGO|S_IWUSR, proc_pdc_root,
259 &led_proc_fops, (void *)LED_NOLCD); /* LED */
260 if (!ent) return -1;
261 }
262
263 if (led_type == LED_HASLCD)
264 {
265 ent = proc_create_data("lcd", S_IRUGO|S_IWUSR, proc_pdc_root,
266 &led_proc_fops, (void *)LED_HASLCD); /* LCD */
267 if (!ent) return -1;
268 }
269
270 return 0;
271}
272#endif
273
274/*
275 **
276 ** led_ASP_driver()
277 **
278 */
279#define LED_DATA 0x01 /* data to shift (0:on 1:off) */
280#define LED_STROBE 0x02 /* strobe to clock data */
281static void led_ASP_driver(unsigned char leds)
282{
283 int i;
284
285 leds = ~leds;
286 for (i = 0; i < 8; i++) {
287 unsigned char value;
288 value = (leds & 0x80) >> 7;
289 gsc_writeb( value, LED_DATA_REG );
290 gsc_writeb( value | LED_STROBE, LED_DATA_REG );
291 leds <<= 1;
292 }
293}
294
295
296/*
297 **
298 ** led_LASI_driver()
299 **
300 */
301static void led_LASI_driver(unsigned char leds)
302{
303 leds = ~leds;
304 gsc_writeb( leds, LED_DATA_REG );
305}
306
307
308/*
309 **
310 ** led_LCD_driver()
311 **
312 */
313static void led_LCD_driver(unsigned char leds)
314{
315 static int i;
316 static unsigned char mask[4] = { LED_HEARTBEAT, LED_DISK_IO,
317 LED_LAN_RCV, LED_LAN_TX };
318
319 static struct lcd_block * blockp[4] = {
320 &lcd_info.heartbeat,
321 &lcd_info.disk_io,
322 &lcd_info.lan_rcv,
323 &lcd_info.lan_tx
324 };
325
326 /* Convert min_cmd_delay to milliseconds */
327 unsigned int msec_cmd_delay = 1 + (lcd_info.min_cmd_delay / 1000);
328
329 for (i=0; i<4; ++i)
330 {
331 if ((leds & mask[i]) != (lastleds & mask[i]))
332 {
333 gsc_writeb( blockp[i]->command, LCD_CMD_REG );
334 msleep(msec_cmd_delay);
335
336 gsc_writeb( leds & mask[i] ? blockp[i]->on :
337 blockp[i]->off, LCD_DATA_REG );
338 msleep(msec_cmd_delay);
339 }
340 }
341}
342
343
344/*
345 **
346 ** led_get_net_activity()
347 **
348 ** calculate if there was TX- or RX-throughput on the network interfaces
349 ** (analog to dev_get_info() from net/core/dev.c)
350 **
351 */
352static __inline__ int led_get_net_activity(void)
353{
354#ifndef CONFIG_NET
355 return 0;
356#else
357 static u64 rx_total_last, tx_total_last;
358 u64 rx_total, tx_total;
359 struct net_device *dev;
360 int retval;
361
362 rx_total = tx_total = 0;
363
364 /* we are running as a workqueue task, so we can use an RCU lookup */
365 rcu_read_lock();
366 for_each_netdev_rcu(&init_net, dev) {
367 const struct rtnl_link_stats64 *stats;
368 struct rtnl_link_stats64 temp;
369 struct in_device *in_dev = __in_dev_get_rcu(dev);
370 if (!in_dev || !in_dev->ifa_list)
371 continue;
372 if (ipv4_is_loopback(in_dev->ifa_list->ifa_local))
373 continue;
374 stats = dev_get_stats(dev, &temp);
375 rx_total += stats->rx_packets;
376 tx_total += stats->tx_packets;
377 }
378 rcu_read_unlock();
379
380 retval = 0;
381
382 if (rx_total != rx_total_last) {
383 rx_total_last = rx_total;
384 retval |= LED_LAN_RCV;
385 }
386
387 if (tx_total != tx_total_last) {
388 tx_total_last = tx_total;
389 retval |= LED_LAN_TX;
390 }
391
392 return retval;
393#endif
394}
395
396
397/*
398 **
399 ** led_get_diskio_activity()
400 **
401 ** calculate if there was disk-io in the system
402 **
403 */
404static __inline__ int led_get_diskio_activity(void)
405{
406 static unsigned long last_pgpgin, last_pgpgout;
407 unsigned long events[NR_VM_EVENT_ITEMS];
408 int changed;
409
410 all_vm_events(events);
411
412 /* Just use a very simple calculation here. Do not care about overflow,
413 since we only want to know if there was activity or not. */
414 changed = (events[PGPGIN] != last_pgpgin) ||
415 (events[PGPGOUT] != last_pgpgout);
416 last_pgpgin = events[PGPGIN];
417 last_pgpgout = events[PGPGOUT];
418
419 return (changed ? LED_DISK_IO : 0);
420}
421
422
423
424/*
425 ** led_work_func()
426 **
427 ** manages when and which chassis LCD/LED gets updated
428
429 TODO:
430 - display load average (older machines like 715/64 have 4 "free" LED's for that)
431 - optimizations
432 */
433
434#define HEARTBEAT_LEN (HZ*10/100)
435#define HEARTBEAT_2ND_RANGE_START (HZ*28/100)
436#define HEARTBEAT_2ND_RANGE_END (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN)
437
438#define LED_UPDATE_INTERVAL (1 + (HZ*19/1000))
439
440static void led_work_func (struct work_struct *unused)
441{
442 static unsigned long last_jiffies;
443 static unsigned long count_HZ; /* counter in range 0..HZ */
444 unsigned char currentleds = 0; /* stores current value of the LEDs */
445
446 /* exit if not initialized */
447 if (!led_func_ptr)
448 return;
449
450 /* increment the heartbeat timekeeper */
451 count_HZ += jiffies - last_jiffies;
452 last_jiffies = jiffies;
453 if (count_HZ >= HZ)
454 count_HZ = 0;
455
456 if (likely(led_heartbeat))
457 {
458 /* flash heartbeat-LED like a real heart
459 * (2 x short then a long delay)
460 */
461 if (count_HZ < HEARTBEAT_LEN ||
462 (count_HZ >= HEARTBEAT_2ND_RANGE_START &&
463 count_HZ < HEARTBEAT_2ND_RANGE_END))
464 currentleds |= LED_HEARTBEAT;
465 }
466
467 if (likely(led_lanrxtx)) currentleds |= led_get_net_activity();
468 if (likely(led_diskio)) currentleds |= led_get_diskio_activity();
469
470 /* blink LEDs if we got an Oops (HPMC) */
471 if (unlikely(oops_in_progress)) {
472 if (boot_cpu_data.cpu_type >= pcxl2) {
473 /* newer machines don't have loadavg. LEDs, so we
474 * let all LEDs blink twice per second instead */
475 currentleds = (count_HZ <= (HZ/2)) ? 0 : 0xff;
476 } else {
477 /* old machines: blink loadavg. LEDs twice per second */
478 if (count_HZ <= (HZ/2))
479 currentleds &= ~(LED4|LED5|LED6|LED7);
480 else
481 currentleds |= (LED4|LED5|LED6|LED7);
482 }
483 }
484
485 if (currentleds != lastleds)
486 {
487 led_func_ptr(currentleds); /* Update the LCD/LEDs */
488 lastleds = currentleds;
489 }
490
491 queue_delayed_work(led_wq, &led_task, LED_UPDATE_INTERVAL);
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
502static int led_halt(struct notifier_block *, unsigned long, void *);
503
504static struct notifier_block led_notifier = {
505 .notifier_call = led_halt,
506};
507static int notifier_disabled = 0;
508
509static int led_halt(struct notifier_block *nb, unsigned long event, void *buf)
510{
511 char *txt;
512
513 if (notifier_disabled)
514 return NOTIFY_OK;
515
516 notifier_disabled = 1;
517 switch (event) {
518 case SYS_RESTART: txt = "SYSTEM RESTART";
519 break;
520 case SYS_HALT: txt = "SYSTEM HALT";
521 break;
522 case SYS_POWER_OFF: txt = "SYSTEM POWER OFF";
523 break;
524 default: return NOTIFY_DONE;
525 }
526
527 /* Cancel the work item and delete the queue */
528 if (led_wq) {
529 cancel_delayed_work_sync(&led_task);
530 destroy_workqueue(led_wq);
531 led_wq = NULL;
532 }
533
534 if (lcd_info.model == DISPLAY_MODEL_LCD)
535 lcd_print(txt);
536 else
537 if (led_func_ptr)
538 led_func_ptr(0xff); /* turn all LEDs ON */
539
540 return NOTIFY_OK;
541}
542
543/*
544 ** register_led_driver()
545 **
546 ** registers an external LED or LCD for usage by this driver.
547 ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported.
548 **
549 */
550
551int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg)
552{
553 static int initialized;
554
555 if (initialized || !data_reg)
556 return 1;
557
558 lcd_info.model = model; /* store the values */
559 LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg;
560
561 switch (lcd_info.model) {
562 case DISPLAY_MODEL_LCD:
563 LCD_DATA_REG = data_reg;
564 printk(KERN_INFO "LCD display at %lx,%lx registered\n",
565 LCD_CMD_REG , LCD_DATA_REG);
566 led_func_ptr = led_LCD_driver;
567 led_type = LED_HASLCD;
568 break;
569
570 case DISPLAY_MODEL_LASI:
571 LED_DATA_REG = data_reg;
572 led_func_ptr = led_LASI_driver;
573 printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG);
574 led_type = LED_NOLCD;
575 break;
576
577 case DISPLAY_MODEL_OLD_ASP:
578 LED_DATA_REG = data_reg;
579 led_func_ptr = led_ASP_driver;
580 printk(KERN_INFO "LED (ASP-style) display at %lx registered\n",
581 LED_DATA_REG);
582 led_type = LED_NOLCD;
583 break;
584
585 default:
586 printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n",
587 __func__, lcd_info.model);
588 return 1;
589 }
590
591 /* mark the LCD/LED driver now as initialized and
592 * register to the reboot notifier chain */
593 initialized++;
594 register_reboot_notifier(&led_notifier);
595
596 /* Ensure the work is queued */
597 if (led_wq) {
598 queue_delayed_work(led_wq, &led_task, 0);
599 }
600
601 return 0;
602}
603
604/*
605 ** register_led_regions()
606 **
607 ** register_led_regions() registers the LCD/LED regions for /procfs.
608 ** At bootup - where the initialisation of the LCD/LED normally happens -
609 ** not all internal structures of request_region() are properly set up,
610 ** so that we delay the led-registration until after busdevices_init()
611 ** has been executed.
612 **
613 */
614
615void __init register_led_regions(void)
616{
617 switch (lcd_info.model) {
618 case DISPLAY_MODEL_LCD:
619 request_mem_region((unsigned long)LCD_CMD_REG, 1, "lcd_cmd");
620 request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data");
621 break;
622 case DISPLAY_MODEL_LASI:
623 case DISPLAY_MODEL_OLD_ASP:
624 request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data");
625 break;
626 }
627}
628
629
630/*
631 **
632 ** lcd_print()
633 **
634 ** Displays the given string on the LCD-Display of newer machines.
635 ** lcd_print() disables/enables the timer-based led work queue to
636 ** avoid a race condition while writing the CMD/DATA register pair.
637 **
638 */
639int lcd_print( const char *str )
640{
641 int i;
642
643 if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD)
644 return 0;
645
646 /* temporarily disable the led work task */
647 if (led_wq)
648 cancel_delayed_work_sync(&led_task);
649
650 /* copy display string to buffer for procfs */
651 strlcpy(lcd_text, str, sizeof(lcd_text));
652
653 /* Set LCD Cursor to 1st character */
654 gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG);
655 udelay(lcd_info.min_cmd_delay);
656
657 /* Print the string */
658 for (i=0; i < lcd_info.lcd_width; i++) {
659 if (str && *str)
660 gsc_writeb(*str++, LCD_DATA_REG);
661 else
662 gsc_writeb(' ', LCD_DATA_REG);
663 udelay(lcd_info.min_cmd_delay);
664 }
665
666 /* re-queue the work */
667 if (led_wq) {
668 queue_delayed_work(led_wq, &led_task, 0);
669 }
670
671 return lcd_info.lcd_width;
672}
673
674/*
675 ** led_init()
676 **
677 ** led_init() is called very early in the bootup-process from setup.c
678 ** and asks the PDC for an usable chassis LCD or LED.
679 ** If the PDC doesn't return any info, then the LED
680 ** is detected by lasi.c or asp.c and registered with the
681 ** above functions lasi_led_init() or asp_led_init().
682 ** KittyHawk machines have often a buggy PDC, so that
683 ** we explicitly check for those machines here.
684 */
685
686int __init led_init(void)
687{
688 struct pdc_chassis_info chassis_info;
689 int ret;
690
691 snprintf(lcd_text_default, sizeof(lcd_text_default),
692 "Linux %s", init_utsname()->release);
693
694 /* Work around the buggy PDC of KittyHawk-machines */
695 switch (CPU_HVERSION) {
696 case 0x580: /* KittyHawk DC2-100 (K100) */
697 case 0x581: /* KittyHawk DC3-120 (K210) */
698 case 0x582: /* KittyHawk DC3 100 (K400) */
699 case 0x583: /* KittyHawk DC3 120 (K410) */
700 case 0x58B: /* KittyHawk DC2 100 (K200) */
701 printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "
702 "LED detection skipped.\n", __FILE__, CPU_HVERSION);
703 lcd_no_led_support = 1;
704 goto found; /* use the preinitialized values of lcd_info */
705 }
706
707 /* initialize the struct, so that we can check for valid return values */
708 lcd_info.model = DISPLAY_MODEL_NONE;
709 chassis_info.actcnt = chassis_info.maxcnt = 0;
710
711 ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info));
712 if (ret == PDC_OK) {
713 DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), "
714 "lcd_width=%d, cmd_delay=%u,\n"
715 "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n",
716 __FILE__, lcd_info.model,
717 (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" :
718 (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown",
719 lcd_info.lcd_width, lcd_info.min_cmd_delay,
720 __FILE__, sizeof(lcd_info),
721 chassis_info.actcnt, chassis_info.maxcnt));
722 DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n",
723 __FILE__, lcd_info.lcd_cmd_reg_addr,
724 lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1,
725 lcd_info.reset_cmd2, lcd_info.act_enable ));
726
727 /* check the results. Some machines have a buggy PDC */
728 if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt)
729 goto not_found;
730
731 switch (lcd_info.model) {
732 case DISPLAY_MODEL_LCD: /* LCD display */
733 if (chassis_info.actcnt <
734 offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)
735 goto not_found;
736 if (!lcd_info.act_enable) {
737 DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n"));
738 goto not_found;
739 }
740 break;
741
742 case DISPLAY_MODEL_NONE: /* no LED or LCD available */
743 printk(KERN_INFO "PDC reported no LCD or LED.\n");
744 goto not_found;
745
746 case DISPLAY_MODEL_LASI: /* Lasi style 8 bit LED display */
747 if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32)
748 goto not_found;
749 break;
750
751 default:
752 printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n",
753 lcd_info.model);
754 goto not_found;
755 } /* switch() */
756
757found:
758 /* register the LCD/LED driver */
759 register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG);
760 return 0;
761
762 } else { /* if() */
763 DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret));
764 }
765
766not_found:
767 lcd_info.model = DISPLAY_MODEL_NONE;
768 return 1;
769}
770
771static void __exit led_exit(void)
772{
773 unregister_reboot_notifier(&led_notifier);
774 return;
775}
776
777#ifdef CONFIG_PROC_FS
778module_init(led_create_procfs)
779#endif
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Chassis LCD/LED driver for HP-PARISC workstations
4 *
5 * (c) Copyright 2000 Red Hat Software
6 * (c) Copyright 2000 Helge Deller <hdeller@redhat.com>
7 * (c) Copyright 2001-2009 Helge Deller <deller@gmx.de>
8 * (c) Copyright 2001 Randolph Chung <tausq@debian.org>
9 *
10 * TODO:
11 * - speed-up calculations with inlined assembler
12 * - interface to write to second row of LCD from /proc (if technically possible)
13 *
14 * Changes:
15 * - Audit copy_from_user in led_proc_write.
16 * Daniele Bellucci <bellucda@tiscali.it>
17 * - Switch from using a tasklet to a work queue, so the led_LCD_driver
18 * can sleep.
19 * David Pye <dmp@davidmpye.dyndns.org>
20 */
21
22#include <linux/module.h>
23#include <linux/stddef.h> /* for offsetof() */
24#include <linux/init.h>
25#include <linux/types.h>
26#include <linux/ioport.h>
27#include <linux/utsname.h>
28#include <linux/capability.h>
29#include <linux/delay.h>
30#include <linux/netdevice.h>
31#include <linux/inetdevice.h>
32#include <linux/in.h>
33#include <linux/interrupt.h>
34#include <linux/kernel_stat.h>
35#include <linux/reboot.h>
36#include <linux/proc_fs.h>
37#include <linux/seq_file.h>
38#include <linux/ctype.h>
39#include <linux/blkdev.h>
40#include <linux/workqueue.h>
41#include <linux/rcupdate.h>
42#include <asm/io.h>
43#include <asm/processor.h>
44#include <asm/hardware.h>
45#include <asm/param.h> /* HZ */
46#include <asm/led.h>
47#include <asm/pdc.h>
48#include <linux/uaccess.h>
49
50/* The control of the LEDs and LCDs on PARISC-machines have to be done
51 completely in software. The necessary calculations are done in a work queue
52 task which is scheduled regularly, and since the calculations may consume a
53 relatively large amount of CPU time, some of the calculations can be
54 turned off with the following variables (controlled via procfs) */
55
56static int led_type __read_mostly = -1;
57static unsigned char lastleds; /* LED state from most recent update */
58static unsigned int led_heartbeat __read_mostly = 1;
59static unsigned int led_diskio __read_mostly = 1;
60static unsigned int led_lanrxtx __read_mostly = 1;
61static char lcd_text[32] __read_mostly;
62static char lcd_text_default[32] __read_mostly;
63static int lcd_no_led_support __read_mostly = 0; /* KittyHawk doesn't support LED on its LCD */
64
65
66static struct workqueue_struct *led_wq;
67static void led_work_func(struct work_struct *);
68static DECLARE_DELAYED_WORK(led_task, led_work_func);
69
70#if 0
71#define DPRINTK(x) printk x
72#else
73#define DPRINTK(x)
74#endif
75
76struct lcd_block {
77 unsigned char command; /* stores the command byte */
78 unsigned char on; /* value for turning LED on */
79 unsigned char off; /* value for turning LED off */
80};
81
82/* Structure returned by PDC_RETURN_CHASSIS_INFO */
83/* NOTE: we use unsigned long:16 two times, since the following member
84 lcd_cmd_reg_addr needs to be 64bit aligned on 64bit PA2.0-machines */
85struct pdc_chassis_lcd_info_ret_block {
86 unsigned long model:16; /* DISPLAY_MODEL_XXXX */
87 unsigned long lcd_width:16; /* width of the LCD in chars (DISPLAY_MODEL_LCD only) */
88 unsigned long lcd_cmd_reg_addr; /* ptr to LCD cmd-register & data ptr for LED */
89 unsigned long lcd_data_reg_addr; /* ptr to LCD data-register (LCD only) */
90 unsigned int min_cmd_delay; /* delay in uS after cmd-write (LCD only) */
91 unsigned char reset_cmd1; /* command #1 for writing LCD string (LCD only) */
92 unsigned char reset_cmd2; /* command #2 for writing LCD string (LCD only) */
93 unsigned char act_enable; /* 0 = no activity (LCD only) */
94 struct lcd_block heartbeat;
95 struct lcd_block disk_io;
96 struct lcd_block lan_rcv;
97 struct lcd_block lan_tx;
98 char _pad;
99};
100
101
102/* LCD_CMD and LCD_DATA for KittyHawk machines */
103#define KITTYHAWK_LCD_CMD F_EXTEND(0xf0190000UL) /* 64bit-ready */
104#define KITTYHAWK_LCD_DATA (KITTYHAWK_LCD_CMD+1)
105
106/* lcd_info is pre-initialized to the values needed to program KittyHawk LCD's
107 * HP seems to have used Sharp/Hitachi HD44780 LCDs most of the time. */
108static struct pdc_chassis_lcd_info_ret_block
109lcd_info __attribute__((aligned(8))) __read_mostly =
110{
111 .model = DISPLAY_MODEL_LCD,
112 .lcd_width = 16,
113 .lcd_cmd_reg_addr = KITTYHAWK_LCD_CMD,
114 .lcd_data_reg_addr = KITTYHAWK_LCD_DATA,
115 .min_cmd_delay = 80,
116 .reset_cmd1 = 0x80,
117 .reset_cmd2 = 0xc0,
118};
119
120
121/* direct access to some of the lcd_info variables */
122#define LCD_CMD_REG lcd_info.lcd_cmd_reg_addr
123#define LCD_DATA_REG lcd_info.lcd_data_reg_addr
124#define LED_DATA_REG lcd_info.lcd_cmd_reg_addr /* LASI & ASP only */
125
126#define LED_HASLCD 1
127#define LED_NOLCD 0
128
129/* The workqueue must be created at init-time */
130static int start_task(void)
131{
132 /* Display the default text now */
133 if (led_type == LED_HASLCD) lcd_print( lcd_text_default );
134
135 /* KittyHawk has no LED support on its LCD */
136 if (lcd_no_led_support) return 0;
137
138 /* Create the work queue and queue the LED task */
139 led_wq = create_singlethread_workqueue("led_wq");
140 queue_delayed_work(led_wq, &led_task, 0);
141
142 return 0;
143}
144
145device_initcall(start_task);
146
147/* ptr to LCD/LED-specific function */
148static void (*led_func_ptr) (unsigned char) __read_mostly;
149
150#ifdef CONFIG_PROC_FS
151static int led_proc_show(struct seq_file *m, void *v)
152{
153 switch ((long)m->private)
154 {
155 case LED_NOLCD:
156 seq_printf(m, "Heartbeat: %d\n", led_heartbeat);
157 seq_printf(m, "Disk IO: %d\n", led_diskio);
158 seq_printf(m, "LAN Rx/Tx: %d\n", led_lanrxtx);
159 break;
160 case LED_HASLCD:
161 seq_printf(m, "%s\n", lcd_text);
162 break;
163 default:
164 return 0;
165 }
166 return 0;
167}
168
169static int led_proc_open(struct inode *inode, struct file *file)
170{
171 return single_open(file, led_proc_show, PDE_DATA(inode));
172}
173
174
175static ssize_t led_proc_write(struct file *file, const char __user *buf,
176 size_t count, loff_t *pos)
177{
178 void *data = PDE_DATA(file_inode(file));
179 char *cur, lbuf[32];
180 int d;
181
182 if (!capable(CAP_SYS_ADMIN))
183 return -EACCES;
184
185 if (count >= sizeof(lbuf))
186 count = sizeof(lbuf)-1;
187
188 if (copy_from_user(lbuf, buf, count))
189 return -EFAULT;
190 lbuf[count] = 0;
191
192 cur = lbuf;
193
194 switch ((long)data)
195 {
196 case LED_NOLCD:
197 d = *cur++ - '0';
198 if (d != 0 && d != 1) goto parse_error;
199 led_heartbeat = d;
200
201 if (*cur++ != ' ') goto parse_error;
202
203 d = *cur++ - '0';
204 if (d != 0 && d != 1) goto parse_error;
205 led_diskio = d;
206
207 if (*cur++ != ' ') goto parse_error;
208
209 d = *cur++ - '0';
210 if (d != 0 && d != 1) goto parse_error;
211 led_lanrxtx = d;
212
213 break;
214 case LED_HASLCD:
215 if (*cur && cur[strlen(cur)-1] == '\n')
216 cur[strlen(cur)-1] = 0;
217 if (*cur == 0)
218 cur = lcd_text_default;
219 lcd_print(cur);
220 break;
221 default:
222 return 0;
223 }
224
225 return count;
226
227parse_error:
228 if ((long)data == LED_NOLCD)
229 printk(KERN_CRIT "Parse error: expect \"n n n\" (n == 0 or 1) for heartbeat,\ndisk io and lan tx/rx indicators\n");
230 return -EINVAL;
231}
232
233static const struct file_operations led_proc_fops = {
234 .owner = THIS_MODULE,
235 .open = led_proc_open,
236 .read = seq_read,
237 .llseek = seq_lseek,
238 .release = single_release,
239 .write = led_proc_write,
240};
241
242static int __init led_create_procfs(void)
243{
244 struct proc_dir_entry *proc_pdc_root = NULL;
245 struct proc_dir_entry *ent;
246
247 if (led_type == -1) return -1;
248
249 proc_pdc_root = proc_mkdir("pdc", NULL);
250 if (!proc_pdc_root) return -1;
251
252 if (!lcd_no_led_support)
253 {
254 ent = proc_create_data("led", S_IRUGO|S_IWUSR, proc_pdc_root,
255 &led_proc_fops, (void *)LED_NOLCD); /* LED */
256 if (!ent) return -1;
257 }
258
259 if (led_type == LED_HASLCD)
260 {
261 ent = proc_create_data("lcd", S_IRUGO|S_IWUSR, proc_pdc_root,
262 &led_proc_fops, (void *)LED_HASLCD); /* LCD */
263 if (!ent) return -1;
264 }
265
266 return 0;
267}
268#endif
269
270/*
271 **
272 ** led_ASP_driver()
273 **
274 */
275#define LED_DATA 0x01 /* data to shift (0:on 1:off) */
276#define LED_STROBE 0x02 /* strobe to clock data */
277static void led_ASP_driver(unsigned char leds)
278{
279 int i;
280
281 leds = ~leds;
282 for (i = 0; i < 8; i++) {
283 unsigned char value;
284 value = (leds & 0x80) >> 7;
285 gsc_writeb( value, LED_DATA_REG );
286 gsc_writeb( value | LED_STROBE, LED_DATA_REG );
287 leds <<= 1;
288 }
289}
290
291
292/*
293 **
294 ** led_LASI_driver()
295 **
296 */
297static void led_LASI_driver(unsigned char leds)
298{
299 leds = ~leds;
300 gsc_writeb( leds, LED_DATA_REG );
301}
302
303
304/*
305 **
306 ** led_LCD_driver()
307 **
308 */
309static void led_LCD_driver(unsigned char leds)
310{
311 static int i;
312 static unsigned char mask[4] = { LED_HEARTBEAT, LED_DISK_IO,
313 LED_LAN_RCV, LED_LAN_TX };
314
315 static struct lcd_block * blockp[4] = {
316 &lcd_info.heartbeat,
317 &lcd_info.disk_io,
318 &lcd_info.lan_rcv,
319 &lcd_info.lan_tx
320 };
321
322 /* Convert min_cmd_delay to milliseconds */
323 unsigned int msec_cmd_delay = 1 + (lcd_info.min_cmd_delay / 1000);
324
325 for (i=0; i<4; ++i)
326 {
327 if ((leds & mask[i]) != (lastleds & mask[i]))
328 {
329 gsc_writeb( blockp[i]->command, LCD_CMD_REG );
330 msleep(msec_cmd_delay);
331
332 gsc_writeb( leds & mask[i] ? blockp[i]->on :
333 blockp[i]->off, LCD_DATA_REG );
334 msleep(msec_cmd_delay);
335 }
336 }
337}
338
339
340/*
341 **
342 ** led_get_net_activity()
343 **
344 ** calculate if there was TX- or RX-throughput on the network interfaces
345 ** (analog to dev_get_info() from net/core/dev.c)
346 **
347 */
348static __inline__ int led_get_net_activity(void)
349{
350#ifndef CONFIG_NET
351 return 0;
352#else
353 static u64 rx_total_last, tx_total_last;
354 u64 rx_total, tx_total;
355 struct net_device *dev;
356 int retval;
357
358 rx_total = tx_total = 0;
359
360 /* we are running as a workqueue task, so we can use an RCU lookup */
361 rcu_read_lock();
362 for_each_netdev_rcu(&init_net, dev) {
363 const struct rtnl_link_stats64 *stats;
364 struct rtnl_link_stats64 temp;
365 struct in_device *in_dev = __in_dev_get_rcu(dev);
366 if (!in_dev || !in_dev->ifa_list)
367 continue;
368 if (ipv4_is_loopback(in_dev->ifa_list->ifa_local))
369 continue;
370 stats = dev_get_stats(dev, &temp);
371 rx_total += stats->rx_packets;
372 tx_total += stats->tx_packets;
373 }
374 rcu_read_unlock();
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 */
400static __inline__ int led_get_diskio_activity(void)
401{
402 static unsigned long last_pgpgin, last_pgpgout;
403 unsigned long events[NR_VM_EVENT_ITEMS];
404 int changed;
405
406 all_vm_events(events);
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 = (events[PGPGIN] != last_pgpgin) ||
411 (events[PGPGOUT] != last_pgpgout);
412 last_pgpgin = events[PGPGIN];
413 last_pgpgout = events[PGPGOUT];
414
415 return (changed ? LED_DISK_IO : 0);
416}
417
418
419
420/*
421 ** led_work_func()
422 **
423 ** manages when and which chassis LCD/LED gets updated
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*10/100)
431#define HEARTBEAT_2ND_RANGE_START (HZ*28/100)
432#define HEARTBEAT_2ND_RANGE_END (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN)
433
434#define LED_UPDATE_INTERVAL (1 + (HZ*19/1000))
435
436static void led_work_func (struct work_struct *unused)
437{
438 static unsigned long last_jiffies;
439 static unsigned long count_HZ; /* counter in range 0..HZ */
440 unsigned char currentleds = 0; /* stores current value of the LEDs */
441
442 /* exit if not initialized */
443 if (!led_func_ptr)
444 return;
445
446 /* increment the heartbeat timekeeper */
447 count_HZ += jiffies - last_jiffies;
448 last_jiffies = jiffies;
449 if (count_HZ >= HZ)
450 count_HZ = 0;
451
452 if (likely(led_heartbeat))
453 {
454 /* flash heartbeat-LED like a real heart
455 * (2 x short then a long delay)
456 */
457 if (count_HZ < HEARTBEAT_LEN ||
458 (count_HZ >= HEARTBEAT_2ND_RANGE_START &&
459 count_HZ < HEARTBEAT_2ND_RANGE_END))
460 currentleds |= LED_HEARTBEAT;
461 }
462
463 if (likely(led_lanrxtx)) currentleds |= led_get_net_activity();
464 if (likely(led_diskio)) currentleds |= led_get_diskio_activity();
465
466 /* blink LEDs if we got an Oops (HPMC) */
467 if (unlikely(oops_in_progress)) {
468 if (boot_cpu_data.cpu_type >= pcxl2) {
469 /* newer machines don't have loadavg. LEDs, so we
470 * let all LEDs blink twice per second instead */
471 currentleds = (count_HZ <= (HZ/2)) ? 0 : 0xff;
472 } else {
473 /* old machines: blink loadavg. LEDs twice per second */
474 if (count_HZ <= (HZ/2))
475 currentleds &= ~(LED4|LED5|LED6|LED7);
476 else
477 currentleds |= (LED4|LED5|LED6|LED7);
478 }
479 }
480
481 if (currentleds != lastleds)
482 {
483 led_func_ptr(currentleds); /* Update the LCD/LEDs */
484 lastleds = currentleds;
485 }
486
487 queue_delayed_work(led_wq, &led_task, LED_UPDATE_INTERVAL);
488}
489
490/*
491 ** led_halt()
492 **
493 ** called by the reboot notifier chain at shutdown and stops all
494 ** LED/LCD activities.
495 **
496 */
497
498static int led_halt(struct notifier_block *, unsigned long, void *);
499
500static struct notifier_block led_notifier = {
501 .notifier_call = led_halt,
502};
503static int notifier_disabled = 0;
504
505static int led_halt(struct notifier_block *nb, unsigned long event, void *buf)
506{
507 char *txt;
508
509 if (notifier_disabled)
510 return NOTIFY_OK;
511
512 notifier_disabled = 1;
513 switch (event) {
514 case SYS_RESTART: txt = "SYSTEM RESTART";
515 break;
516 case SYS_HALT: txt = "SYSTEM HALT";
517 break;
518 case SYS_POWER_OFF: txt = "SYSTEM POWER OFF";
519 break;
520 default: return NOTIFY_DONE;
521 }
522
523 /* Cancel the work item and delete the queue */
524 if (led_wq) {
525 cancel_delayed_work_sync(&led_task);
526 destroy_workqueue(led_wq);
527 led_wq = NULL;
528 }
529
530 if (lcd_info.model == DISPLAY_MODEL_LCD)
531 lcd_print(txt);
532 else
533 if (led_func_ptr)
534 led_func_ptr(0xff); /* turn all LEDs ON */
535
536 return NOTIFY_OK;
537}
538
539/*
540 ** register_led_driver()
541 **
542 ** registers an external LED or LCD for usage by this driver.
543 ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported.
544 **
545 */
546
547int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg)
548{
549 static int initialized;
550
551 if (initialized || !data_reg)
552 return 1;
553
554 lcd_info.model = model; /* store the values */
555 LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg;
556
557 switch (lcd_info.model) {
558 case DISPLAY_MODEL_LCD:
559 LCD_DATA_REG = data_reg;
560 printk(KERN_INFO "LCD display at %lx,%lx registered\n",
561 LCD_CMD_REG , LCD_DATA_REG);
562 led_func_ptr = led_LCD_driver;
563 led_type = LED_HASLCD;
564 break;
565
566 case DISPLAY_MODEL_LASI:
567 /* Skip to register LED in QEMU */
568 if (running_on_qemu)
569 return 1;
570 LED_DATA_REG = data_reg;
571 led_func_ptr = led_LASI_driver;
572 printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG);
573 led_type = LED_NOLCD;
574 break;
575
576 case DISPLAY_MODEL_OLD_ASP:
577 LED_DATA_REG = data_reg;
578 led_func_ptr = led_ASP_driver;
579 printk(KERN_INFO "LED (ASP-style) display at %lx registered\n",
580 LED_DATA_REG);
581 led_type = LED_NOLCD;
582 break;
583
584 default:
585 printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n",
586 __func__, lcd_info.model);
587 return 1;
588 }
589
590 /* mark the LCD/LED driver now as initialized and
591 * register to the reboot notifier chain */
592 initialized++;
593 register_reboot_notifier(&led_notifier);
594
595 /* Ensure the work is queued */
596 if (led_wq) {
597 queue_delayed_work(led_wq, &led_task, 0);
598 }
599
600 return 0;
601}
602
603/*
604 ** register_led_regions()
605 **
606 ** register_led_regions() registers the LCD/LED regions for /procfs.
607 ** At bootup - where the initialisation of the LCD/LED normally happens -
608 ** not all internal structures of request_region() are properly set up,
609 ** so that we delay the led-registration until after busdevices_init()
610 ** has been executed.
611 **
612 */
613
614void __init register_led_regions(void)
615{
616 switch (lcd_info.model) {
617 case DISPLAY_MODEL_LCD:
618 request_mem_region((unsigned long)LCD_CMD_REG, 1, "lcd_cmd");
619 request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data");
620 break;
621 case DISPLAY_MODEL_LASI:
622 case DISPLAY_MODEL_OLD_ASP:
623 request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data");
624 break;
625 }
626}
627
628
629/*
630 **
631 ** lcd_print()
632 **
633 ** Displays the given string on the LCD-Display of newer machines.
634 ** lcd_print() disables/enables the timer-based led work queue to
635 ** avoid a race condition while writing the CMD/DATA register pair.
636 **
637 */
638int lcd_print( const char *str )
639{
640 int i;
641
642 if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD)
643 return 0;
644
645 /* temporarily disable the led work task */
646 if (led_wq)
647 cancel_delayed_work_sync(&led_task);
648
649 /* copy display string to buffer for procfs */
650 strlcpy(lcd_text, str, sizeof(lcd_text));
651
652 /* Set LCD Cursor to 1st character */
653 gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG);
654 udelay(lcd_info.min_cmd_delay);
655
656 /* Print the string */
657 for (i=0; i < lcd_info.lcd_width; i++) {
658 if (str && *str)
659 gsc_writeb(*str++, LCD_DATA_REG);
660 else
661 gsc_writeb(' ', LCD_DATA_REG);
662 udelay(lcd_info.min_cmd_delay);
663 }
664
665 /* re-queue the work */
666 if (led_wq) {
667 queue_delayed_work(led_wq, &led_task, 0);
668 }
669
670 return lcd_info.lcd_width;
671}
672
673/*
674 ** led_init()
675 **
676 ** led_init() is called very early in the bootup-process from setup.c
677 ** and asks the PDC for an usable chassis LCD or LED.
678 ** If the PDC doesn't return any info, then the LED
679 ** is detected by lasi.c or asp.c and registered with the
680 ** above functions lasi_led_init() or asp_led_init().
681 ** KittyHawk machines have often a buggy PDC, so that
682 ** we explicitly check for those machines here.
683 */
684
685int __init led_init(void)
686{
687 struct pdc_chassis_info chassis_info;
688 int ret;
689
690 snprintf(lcd_text_default, sizeof(lcd_text_default),
691 "Linux %s", init_utsname()->release);
692
693 /* Work around the buggy PDC of KittyHawk-machines */
694 switch (CPU_HVERSION) {
695 case 0x580: /* KittyHawk DC2-100 (K100) */
696 case 0x581: /* KittyHawk DC3-120 (K210) */
697 case 0x582: /* KittyHawk DC3 100 (K400) */
698 case 0x583: /* KittyHawk DC3 120 (K410) */
699 case 0x58B: /* KittyHawk DC2 100 (K200) */
700 printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "
701 "LED detection skipped.\n", __FILE__, CPU_HVERSION);
702 lcd_no_led_support = 1;
703 goto found; /* use the preinitialized values of lcd_info */
704 }
705
706 /* initialize the struct, so that we can check for valid return values */
707 lcd_info.model = DISPLAY_MODEL_NONE;
708 chassis_info.actcnt = chassis_info.maxcnt = 0;
709
710 ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info));
711 if (ret == PDC_OK) {
712 DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), "
713 "lcd_width=%d, cmd_delay=%u,\n"
714 "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n",
715 __FILE__, lcd_info.model,
716 (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" :
717 (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown",
718 lcd_info.lcd_width, lcd_info.min_cmd_delay,
719 __FILE__, sizeof(lcd_info),
720 chassis_info.actcnt, chassis_info.maxcnt));
721 DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n",
722 __FILE__, lcd_info.lcd_cmd_reg_addr,
723 lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1,
724 lcd_info.reset_cmd2, lcd_info.act_enable ));
725
726 /* check the results. Some machines have a buggy PDC */
727 if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt)
728 goto not_found;
729
730 switch (lcd_info.model) {
731 case DISPLAY_MODEL_LCD: /* LCD display */
732 if (chassis_info.actcnt <
733 offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)
734 goto not_found;
735 if (!lcd_info.act_enable) {
736 DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n"));
737 goto not_found;
738 }
739 break;
740
741 case DISPLAY_MODEL_NONE: /* no LED or LCD available */
742 printk(KERN_INFO "PDC reported no LCD or LED.\n");
743 goto not_found;
744
745 case DISPLAY_MODEL_LASI: /* Lasi style 8 bit LED display */
746 if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32)
747 goto not_found;
748 break;
749
750 default:
751 printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n",
752 lcd_info.model);
753 goto not_found;
754 } /* switch() */
755
756found:
757 /* register the LCD/LED driver */
758 register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG);
759 return 0;
760
761 } else { /* if() */
762 DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret));
763 }
764
765not_found:
766 lcd_info.model = DISPLAY_MODEL_NONE;
767 return 1;
768}
769
770static void __exit led_exit(void)
771{
772 unregister_reboot_notifier(&led_notifier);
773 return;
774}
775
776#ifdef CONFIG_PROC_FS
777module_init(led_create_procfs)
778#endif