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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 proc_ops led_proc_ops = {
234 .proc_open = led_proc_open,
235 .proc_read = seq_read,
236 .proc_lseek = seq_lseek,
237 .proc_release = single_release,
238 .proc_write = led_proc_write,
239};
240
241static int __init led_create_procfs(void)
242{
243 struct proc_dir_entry *proc_pdc_root = NULL;
244 struct proc_dir_entry *ent;
245
246 if (led_type == -1) return -1;
247
248 proc_pdc_root = proc_mkdir("pdc", NULL);
249 if (!proc_pdc_root) return -1;
250
251 if (!lcd_no_led_support)
252 {
253 ent = proc_create_data("led", S_IRUGO|S_IWUSR, proc_pdc_root,
254 &led_proc_ops, (void *)LED_NOLCD); /* LED */
255 if (!ent) return -1;
256 }
257
258 if (led_type == LED_HASLCD)
259 {
260 ent = proc_create_data("lcd", S_IRUGO|S_IWUSR, proc_pdc_root,
261 &led_proc_ops, (void *)LED_HASLCD); /* LCD */
262 if (!ent) return -1;
263 }
264
265 return 0;
266}
267#endif
268
269/*
270 **
271 ** led_ASP_driver()
272 **
273 */
274#define LED_DATA 0x01 /* data to shift (0:on 1:off) */
275#define LED_STROBE 0x02 /* strobe to clock data */
276static void led_ASP_driver(unsigned char leds)
277{
278 int i;
279
280 leds = ~leds;
281 for (i = 0; i < 8; i++) {
282 unsigned char value;
283 value = (leds & 0x80) >> 7;
284 gsc_writeb( value, LED_DATA_REG );
285 gsc_writeb( value | LED_STROBE, LED_DATA_REG );
286 leds <<= 1;
287 }
288}
289
290
291/*
292 **
293 ** led_LASI_driver()
294 **
295 */
296static void led_LASI_driver(unsigned char leds)
297{
298 leds = ~leds;
299 gsc_writeb( leds, LED_DATA_REG );
300}
301
302
303/*
304 **
305 ** led_LCD_driver()
306 **
307 */
308static void led_LCD_driver(unsigned char leds)
309{
310 static int i;
311 static unsigned char mask[4] = { LED_HEARTBEAT, LED_DISK_IO,
312 LED_LAN_RCV, LED_LAN_TX };
313
314 static struct lcd_block * blockp[4] = {
315 &lcd_info.heartbeat,
316 &lcd_info.disk_io,
317 &lcd_info.lan_rcv,
318 &lcd_info.lan_tx
319 };
320
321 /* Convert min_cmd_delay to milliseconds */
322 unsigned int msec_cmd_delay = 1 + (lcd_info.min_cmd_delay / 1000);
323
324 for (i=0; i<4; ++i)
325 {
326 if ((leds & mask[i]) != (lastleds & mask[i]))
327 {
328 gsc_writeb( blockp[i]->command, LCD_CMD_REG );
329 msleep(msec_cmd_delay);
330
331 gsc_writeb( leds & mask[i] ? blockp[i]->on :
332 blockp[i]->off, LCD_DATA_REG );
333 msleep(msec_cmd_delay);
334 }
335 }
336}
337
338
339/*
340 **
341 ** led_get_net_activity()
342 **
343 ** calculate if there was TX- or RX-throughput on the network interfaces
344 ** (analog to dev_get_info() from net/core/dev.c)
345 **
346 */
347static __inline__ int led_get_net_activity(void)
348{
349#ifndef CONFIG_NET
350 return 0;
351#else
352 static u64 rx_total_last, tx_total_last;
353 u64 rx_total, tx_total;
354 struct net_device *dev;
355 int retval;
356
357 rx_total = tx_total = 0;
358
359 /* we are running as a workqueue task, so we can use an RCU lookup */
360 rcu_read_lock();
361 for_each_netdev_rcu(&init_net, dev) {
362 const struct rtnl_link_stats64 *stats;
363 struct rtnl_link_stats64 temp;
364 struct in_device *in_dev = __in_dev_get_rcu(dev);
365 if (!in_dev || !in_dev->ifa_list)
366 continue;
367 if (ipv4_is_loopback(in_dev->ifa_list->ifa_local))
368 continue;
369 stats = dev_get_stats(dev, &temp);
370 rx_total += stats->rx_packets;
371 tx_total += stats->tx_packets;
372 }
373 rcu_read_unlock();
374
375 retval = 0;
376
377 if (rx_total != rx_total_last) {
378 rx_total_last = rx_total;
379 retval |= LED_LAN_RCV;
380 }
381
382 if (tx_total != tx_total_last) {
383 tx_total_last = tx_total;
384 retval |= LED_LAN_TX;
385 }
386
387 return retval;
388#endif
389}
390
391
392/*
393 **
394 ** led_get_diskio_activity()
395 **
396 ** calculate if there was disk-io in the system
397 **
398 */
399static __inline__ int led_get_diskio_activity(void)
400{
401 static unsigned long last_pgpgin, last_pgpgout;
402 unsigned long events[NR_VM_EVENT_ITEMS];
403 int changed;
404
405 all_vm_events(events);
406
407 /* Just use a very simple calculation here. Do not care about overflow,
408 since we only want to know if there was activity or not. */
409 changed = (events[PGPGIN] != last_pgpgin) ||
410 (events[PGPGOUT] != last_pgpgout);
411 last_pgpgin = events[PGPGIN];
412 last_pgpgout = events[PGPGOUT];
413
414 return (changed ? LED_DISK_IO : 0);
415}
416
417
418
419/*
420 ** led_work_func()
421 **
422 ** manages when and which chassis LCD/LED gets updated
423
424 TODO:
425 - display load average (older machines like 715/64 have 4 "free" LED's for that)
426 - optimizations
427 */
428
429#define HEARTBEAT_LEN (HZ*10/100)
430#define HEARTBEAT_2ND_RANGE_START (HZ*28/100)
431#define HEARTBEAT_2ND_RANGE_END (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN)
432
433#define LED_UPDATE_INTERVAL (1 + (HZ*19/1000))
434
435static void led_work_func (struct work_struct *unused)
436{
437 static unsigned long last_jiffies;
438 static unsigned long count_HZ; /* counter in range 0..HZ */
439 unsigned char currentleds = 0; /* stores current value of the LEDs */
440
441 /* exit if not initialized */
442 if (!led_func_ptr)
443 return;
444
445 /* increment the heartbeat timekeeper */
446 count_HZ += jiffies - last_jiffies;
447 last_jiffies = jiffies;
448 if (count_HZ >= HZ)
449 count_HZ = 0;
450
451 if (likely(led_heartbeat))
452 {
453 /* flash heartbeat-LED like a real heart
454 * (2 x short then a long delay)
455 */
456 if (count_HZ < HEARTBEAT_LEN ||
457 (count_HZ >= HEARTBEAT_2ND_RANGE_START &&
458 count_HZ < HEARTBEAT_2ND_RANGE_END))
459 currentleds |= LED_HEARTBEAT;
460 }
461
462 if (likely(led_lanrxtx)) currentleds |= led_get_net_activity();
463 if (likely(led_diskio)) currentleds |= led_get_diskio_activity();
464
465 /* blink LEDs if we got an Oops (HPMC) */
466 if (unlikely(oops_in_progress)) {
467 if (boot_cpu_data.cpu_type >= pcxl2) {
468 /* newer machines don't have loadavg. LEDs, so we
469 * let all LEDs blink twice per second instead */
470 currentleds = (count_HZ <= (HZ/2)) ? 0 : 0xff;
471 } else {
472 /* old machines: blink loadavg. LEDs twice per second */
473 if (count_HZ <= (HZ/2))
474 currentleds &= ~(LED4|LED5|LED6|LED7);
475 else
476 currentleds |= (LED4|LED5|LED6|LED7);
477 }
478 }
479
480 if (currentleds != lastleds)
481 {
482 led_func_ptr(currentleds); /* Update the LCD/LEDs */
483 lastleds = currentleds;
484 }
485
486 queue_delayed_work(led_wq, &led_task, LED_UPDATE_INTERVAL);
487}
488
489/*
490 ** led_halt()
491 **
492 ** called by the reboot notifier chain at shutdown and stops all
493 ** LED/LCD activities.
494 **
495 */
496
497static int led_halt(struct notifier_block *, unsigned long, void *);
498
499static struct notifier_block led_notifier = {
500 .notifier_call = led_halt,
501};
502static int notifier_disabled = 0;
503
504static int led_halt(struct notifier_block *nb, unsigned long event, void *buf)
505{
506 char *txt;
507
508 if (notifier_disabled)
509 return NOTIFY_OK;
510
511 notifier_disabled = 1;
512 switch (event) {
513 case SYS_RESTART: txt = "SYSTEM RESTART";
514 break;
515 case SYS_HALT: txt = "SYSTEM HALT";
516 break;
517 case SYS_POWER_OFF: txt = "SYSTEM POWER OFF";
518 break;
519 default: return NOTIFY_DONE;
520 }
521
522 /* Cancel the work item and delete the queue */
523 if (led_wq) {
524 cancel_delayed_work_sync(&led_task);
525 destroy_workqueue(led_wq);
526 led_wq = NULL;
527 }
528
529 if (lcd_info.model == DISPLAY_MODEL_LCD)
530 lcd_print(txt);
531 else
532 if (led_func_ptr)
533 led_func_ptr(0xff); /* turn all LEDs ON */
534
535 return NOTIFY_OK;
536}
537
538/*
539 ** register_led_driver()
540 **
541 ** registers an external LED or LCD for usage by this driver.
542 ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported.
543 **
544 */
545
546int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg)
547{
548 static int initialized;
549
550 if (initialized || !data_reg)
551 return 1;
552
553 lcd_info.model = model; /* store the values */
554 LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg;
555
556 switch (lcd_info.model) {
557 case DISPLAY_MODEL_LCD:
558 LCD_DATA_REG = data_reg;
559 printk(KERN_INFO "LCD display at %lx,%lx registered\n",
560 LCD_CMD_REG , LCD_DATA_REG);
561 led_func_ptr = led_LCD_driver;
562 led_type = LED_HASLCD;
563 break;
564
565 case DISPLAY_MODEL_LASI:
566 /* Skip to register LED in QEMU */
567 if (running_on_qemu)
568 return 1;
569 LED_DATA_REG = data_reg;
570 led_func_ptr = led_LASI_driver;
571 printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG);
572 led_type = LED_NOLCD;
573 break;
574
575 case DISPLAY_MODEL_OLD_ASP:
576 LED_DATA_REG = data_reg;
577 led_func_ptr = led_ASP_driver;
578 printk(KERN_INFO "LED (ASP-style) display at %lx registered\n",
579 LED_DATA_REG);
580 led_type = LED_NOLCD;
581 break;
582
583 default:
584 printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n",
585 __func__, lcd_info.model);
586 return 1;
587 }
588
589 /* mark the LCD/LED driver now as initialized and
590 * register to the reboot notifier chain */
591 initialized++;
592 register_reboot_notifier(&led_notifier);
593
594 /* Ensure the work is queued */
595 if (led_wq) {
596 queue_delayed_work(led_wq, &led_task, 0);
597 }
598
599 return 0;
600}
601
602/*
603 ** register_led_regions()
604 **
605 ** register_led_regions() registers the LCD/LED regions for /procfs.
606 ** At bootup - where the initialisation of the LCD/LED normally happens -
607 ** not all internal structures of request_region() are properly set up,
608 ** so that we delay the led-registration until after busdevices_init()
609 ** has been executed.
610 **
611 */
612
613void __init register_led_regions(void)
614{
615 switch (lcd_info.model) {
616 case DISPLAY_MODEL_LCD:
617 request_mem_region((unsigned long)LCD_CMD_REG, 1, "lcd_cmd");
618 request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data");
619 break;
620 case DISPLAY_MODEL_LASI:
621 case DISPLAY_MODEL_OLD_ASP:
622 request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data");
623 break;
624 }
625}
626
627
628/*
629 **
630 ** lcd_print()
631 **
632 ** Displays the given string on the LCD-Display of newer machines.
633 ** lcd_print() disables/enables the timer-based led work queue to
634 ** avoid a race condition while writing the CMD/DATA register pair.
635 **
636 */
637int lcd_print( const char *str )
638{
639 int i;
640
641 if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD)
642 return 0;
643
644 /* temporarily disable the led work task */
645 if (led_wq)
646 cancel_delayed_work_sync(&led_task);
647
648 /* copy display string to buffer for procfs */
649 strlcpy(lcd_text, str, sizeof(lcd_text));
650
651 /* Set LCD Cursor to 1st character */
652 gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG);
653 udelay(lcd_info.min_cmd_delay);
654
655 /* Print the string */
656 for (i=0; i < lcd_info.lcd_width; i++) {
657 if (str && *str)
658 gsc_writeb(*str++, LCD_DATA_REG);
659 else
660 gsc_writeb(' ', LCD_DATA_REG);
661 udelay(lcd_info.min_cmd_delay);
662 }
663
664 /* re-queue the work */
665 if (led_wq) {
666 queue_delayed_work(led_wq, &led_task, 0);
667 }
668
669 return lcd_info.lcd_width;
670}
671
672/*
673 ** led_init()
674 **
675 ** led_init() is called very early in the bootup-process from setup.c
676 ** and asks the PDC for an usable chassis LCD or LED.
677 ** If the PDC doesn't return any info, then the LED
678 ** is detected by lasi.c or asp.c and registered with the
679 ** above functions lasi_led_init() or asp_led_init().
680 ** KittyHawk machines have often a buggy PDC, so that
681 ** we explicitly check for those machines here.
682 */
683
684int __init led_init(void)
685{
686 struct pdc_chassis_info chassis_info;
687 int ret;
688
689 snprintf(lcd_text_default, sizeof(lcd_text_default),
690 "Linux %s", init_utsname()->release);
691
692 /* Work around the buggy PDC of KittyHawk-machines */
693 switch (CPU_HVERSION) {
694 case 0x580: /* KittyHawk DC2-100 (K100) */
695 case 0x581: /* KittyHawk DC3-120 (K210) */
696 case 0x582: /* KittyHawk DC3 100 (K400) */
697 case 0x583: /* KittyHawk DC3 120 (K410) */
698 case 0x58B: /* KittyHawk DC2 100 (K200) */
699 printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "
700 "LED detection skipped.\n", __FILE__, CPU_HVERSION);
701 lcd_no_led_support = 1;
702 goto found; /* use the preinitialized values of lcd_info */
703 }
704
705 /* initialize the struct, so that we can check for valid return values */
706 lcd_info.model = DISPLAY_MODEL_NONE;
707 chassis_info.actcnt = chassis_info.maxcnt = 0;
708
709 ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info));
710 if (ret == PDC_OK) {
711 DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), "
712 "lcd_width=%d, cmd_delay=%u,\n"
713 "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n",
714 __FILE__, lcd_info.model,
715 (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" :
716 (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown",
717 lcd_info.lcd_width, lcd_info.min_cmd_delay,
718 __FILE__, sizeof(lcd_info),
719 chassis_info.actcnt, chassis_info.maxcnt));
720 DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n",
721 __FILE__, lcd_info.lcd_cmd_reg_addr,
722 lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1,
723 lcd_info.reset_cmd2, lcd_info.act_enable ));
724
725 /* check the results. Some machines have a buggy PDC */
726 if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt)
727 goto not_found;
728
729 switch (lcd_info.model) {
730 case DISPLAY_MODEL_LCD: /* LCD display */
731 if (chassis_info.actcnt <
732 offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)
733 goto not_found;
734 if (!lcd_info.act_enable) {
735 DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n"));
736 goto not_found;
737 }
738 break;
739
740 case DISPLAY_MODEL_NONE: /* no LED or LCD available */
741 printk(KERN_INFO "PDC reported no LCD or LED.\n");
742 goto not_found;
743
744 case DISPLAY_MODEL_LASI: /* Lasi style 8 bit LED display */
745 if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32)
746 goto not_found;
747 break;
748
749 default:
750 printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n",
751 lcd_info.model);
752 goto not_found;
753 } /* switch() */
754
755found:
756 /* register the LCD/LED driver */
757 register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG);
758 return 0;
759
760 } else { /* if() */
761 DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret));
762 }
763
764not_found:
765 lcd_info.model = DISPLAY_MODEL_NONE;
766 return 1;
767}
768
769static void __exit led_exit(void)
770{
771 unregister_reboot_notifier(&led_notifier);
772 return;
773}
774
775#ifdef CONFIG_PROC_FS
776module_init(led_create_procfs)
777#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 proc_ops led_proc_ops = {
234 .proc_open = led_proc_open,
235 .proc_read = seq_read,
236 .proc_lseek = seq_lseek,
237 .proc_release = single_release,
238 .proc_write = led_proc_write,
239};
240
241static int __init led_create_procfs(void)
242{
243 struct proc_dir_entry *proc_pdc_root = NULL;
244 struct proc_dir_entry *ent;
245
246 if (led_type == -1) return -1;
247
248 proc_pdc_root = proc_mkdir("pdc", NULL);
249 if (!proc_pdc_root) return -1;
250
251 if (!lcd_no_led_support)
252 {
253 ent = proc_create_data("led", S_IRUGO|S_IWUSR, proc_pdc_root,
254 &led_proc_ops, (void *)LED_NOLCD); /* LED */
255 if (!ent) return -1;
256 }
257
258 if (led_type == LED_HASLCD)
259 {
260 ent = proc_create_data("lcd", S_IRUGO|S_IWUSR, proc_pdc_root,
261 &led_proc_ops, (void *)LED_HASLCD); /* LCD */
262 if (!ent) return -1;
263 }
264
265 return 0;
266}
267#endif
268
269/*
270 **
271 ** led_ASP_driver()
272 **
273 */
274#define LED_DATA 0x01 /* data to shift (0:on 1:off) */
275#define LED_STROBE 0x02 /* strobe to clock data */
276static void led_ASP_driver(unsigned char leds)
277{
278 int i;
279
280 leds = ~leds;
281 for (i = 0; i < 8; i++) {
282 unsigned char value;
283 value = (leds & 0x80) >> 7;
284 gsc_writeb( value, LED_DATA_REG );
285 gsc_writeb( value | LED_STROBE, LED_DATA_REG );
286 leds <<= 1;
287 }
288}
289
290
291/*
292 **
293 ** led_LASI_driver()
294 **
295 */
296static void led_LASI_driver(unsigned char leds)
297{
298 leds = ~leds;
299 gsc_writeb( leds, LED_DATA_REG );
300}
301
302
303/*
304 **
305 ** led_LCD_driver()
306 **
307 */
308static void led_LCD_driver(unsigned char leds)
309{
310 static int i;
311 static unsigned char mask[4] = { LED_HEARTBEAT, LED_DISK_IO,
312 LED_LAN_RCV, LED_LAN_TX };
313
314 static struct lcd_block * blockp[4] = {
315 &lcd_info.heartbeat,
316 &lcd_info.disk_io,
317 &lcd_info.lan_rcv,
318 &lcd_info.lan_tx
319 };
320
321 /* Convert min_cmd_delay to milliseconds */
322 unsigned int msec_cmd_delay = 1 + (lcd_info.min_cmd_delay / 1000);
323
324 for (i=0; i<4; ++i)
325 {
326 if ((leds & mask[i]) != (lastleds & mask[i]))
327 {
328 gsc_writeb( blockp[i]->command, LCD_CMD_REG );
329 msleep(msec_cmd_delay);
330
331 gsc_writeb( leds & mask[i] ? blockp[i]->on :
332 blockp[i]->off, LCD_DATA_REG );
333 msleep(msec_cmd_delay);
334 }
335 }
336}
337
338
339/*
340 **
341 ** led_get_net_activity()
342 **
343 ** calculate if there was TX- or RX-throughput on the network interfaces
344 ** (analog to dev_get_info() from net/core/dev.c)
345 **
346 */
347static __inline__ int led_get_net_activity(void)
348{
349#ifndef CONFIG_NET
350 return 0;
351#else
352 static u64 rx_total_last, tx_total_last;
353 u64 rx_total, tx_total;
354 struct net_device *dev;
355 int retval;
356
357 rx_total = tx_total = 0;
358
359 /* we are running as a workqueue task, so we can use an RCU lookup */
360 rcu_read_lock();
361 for_each_netdev_rcu(&init_net, dev) {
362 const struct rtnl_link_stats64 *stats;
363 struct rtnl_link_stats64 temp;
364 struct in_device *in_dev = __in_dev_get_rcu(dev);
365 if (!in_dev || !in_dev->ifa_list)
366 continue;
367 if (ipv4_is_loopback(in_dev->ifa_list->ifa_local))
368 continue;
369 stats = dev_get_stats(dev, &temp);
370 rx_total += stats->rx_packets;
371 tx_total += stats->tx_packets;
372 }
373 rcu_read_unlock();
374
375 retval = 0;
376
377 if (rx_total != rx_total_last) {
378 rx_total_last = rx_total;
379 retval |= LED_LAN_RCV;
380 }
381
382 if (tx_total != tx_total_last) {
383 tx_total_last = tx_total;
384 retval |= LED_LAN_TX;
385 }
386
387 return retval;
388#endif
389}
390
391
392/*
393 **
394 ** led_get_diskio_activity()
395 **
396 ** calculate if there was disk-io in the system
397 **
398 */
399static __inline__ int led_get_diskio_activity(void)
400{
401 static unsigned long last_pgpgin, last_pgpgout;
402 unsigned long events[NR_VM_EVENT_ITEMS];
403 int changed;
404
405 all_vm_events(events);
406
407 /* Just use a very simple calculation here. Do not care about overflow,
408 since we only want to know if there was activity or not. */
409 changed = (events[PGPGIN] != last_pgpgin) ||
410 (events[PGPGOUT] != last_pgpgout);
411 last_pgpgin = events[PGPGIN];
412 last_pgpgout = events[PGPGOUT];
413
414 return (changed ? LED_DISK_IO : 0);
415}
416
417
418
419/*
420 ** led_work_func()
421 **
422 ** manages when and which chassis LCD/LED gets updated
423
424 TODO:
425 - display load average (older machines like 715/64 have 4 "free" LED's for that)
426 - optimizations
427 */
428
429#define HEARTBEAT_LEN (HZ*10/100)
430#define HEARTBEAT_2ND_RANGE_START (HZ*28/100)
431#define HEARTBEAT_2ND_RANGE_END (HEARTBEAT_2ND_RANGE_START + HEARTBEAT_LEN)
432
433#define LED_UPDATE_INTERVAL (1 + (HZ*19/1000))
434
435static void led_work_func (struct work_struct *unused)
436{
437 static unsigned long last_jiffies;
438 static unsigned long count_HZ; /* counter in range 0..HZ */
439 unsigned char currentleds = 0; /* stores current value of the LEDs */
440
441 /* exit if not initialized */
442 if (!led_func_ptr)
443 return;
444
445 /* increment the heartbeat timekeeper */
446 count_HZ += jiffies - last_jiffies;
447 last_jiffies = jiffies;
448 if (count_HZ >= HZ)
449 count_HZ = 0;
450
451 if (likely(led_heartbeat))
452 {
453 /* flash heartbeat-LED like a real heart
454 * (2 x short then a long delay)
455 */
456 if (count_HZ < HEARTBEAT_LEN ||
457 (count_HZ >= HEARTBEAT_2ND_RANGE_START &&
458 count_HZ < HEARTBEAT_2ND_RANGE_END))
459 currentleds |= LED_HEARTBEAT;
460 }
461
462 if (likely(led_lanrxtx)) currentleds |= led_get_net_activity();
463 if (likely(led_diskio)) currentleds |= led_get_diskio_activity();
464
465 /* blink LEDs if we got an Oops (HPMC) */
466 if (unlikely(oops_in_progress)) {
467 if (boot_cpu_data.cpu_type >= pcxl2) {
468 /* newer machines don't have loadavg. LEDs, so we
469 * let all LEDs blink twice per second instead */
470 currentleds = (count_HZ <= (HZ/2)) ? 0 : 0xff;
471 } else {
472 /* old machines: blink loadavg. LEDs twice per second */
473 if (count_HZ <= (HZ/2))
474 currentleds &= ~(LED4|LED5|LED6|LED7);
475 else
476 currentleds |= (LED4|LED5|LED6|LED7);
477 }
478 }
479
480 if (currentleds != lastleds)
481 {
482 led_func_ptr(currentleds); /* Update the LCD/LEDs */
483 lastleds = currentleds;
484 }
485
486 queue_delayed_work(led_wq, &led_task, LED_UPDATE_INTERVAL);
487}
488
489/*
490 ** led_halt()
491 **
492 ** called by the reboot notifier chain at shutdown and stops all
493 ** LED/LCD activities.
494 **
495 */
496
497static int led_halt(struct notifier_block *, unsigned long, void *);
498
499static struct notifier_block led_notifier = {
500 .notifier_call = led_halt,
501};
502static int notifier_disabled = 0;
503
504static int led_halt(struct notifier_block *nb, unsigned long event, void *buf)
505{
506 char *txt;
507
508 if (notifier_disabled)
509 return NOTIFY_OK;
510
511 notifier_disabled = 1;
512 switch (event) {
513 case SYS_RESTART: txt = "SYSTEM RESTART";
514 break;
515 case SYS_HALT: txt = "SYSTEM HALT";
516 break;
517 case SYS_POWER_OFF: txt = "SYSTEM POWER OFF";
518 break;
519 default: return NOTIFY_DONE;
520 }
521
522 /* Cancel the work item and delete the queue */
523 if (led_wq) {
524 cancel_delayed_work_sync(&led_task);
525 destroy_workqueue(led_wq);
526 led_wq = NULL;
527 }
528
529 if (lcd_info.model == DISPLAY_MODEL_LCD)
530 lcd_print(txt);
531 else
532 if (led_func_ptr)
533 led_func_ptr(0xff); /* turn all LEDs ON */
534
535 return NOTIFY_OK;
536}
537
538/*
539 ** register_led_driver()
540 **
541 ** registers an external LED or LCD for usage by this driver.
542 ** currently only LCD-, LASI- and ASP-style LCD/LED's are supported.
543 **
544 */
545
546int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg)
547{
548 static int initialized;
549
550 if (initialized || !data_reg)
551 return 1;
552
553 lcd_info.model = model; /* store the values */
554 LCD_CMD_REG = (cmd_reg == LED_CMD_REG_NONE) ? 0 : cmd_reg;
555
556 switch (lcd_info.model) {
557 case DISPLAY_MODEL_LCD:
558 LCD_DATA_REG = data_reg;
559 printk(KERN_INFO "LCD display at %lx,%lx registered\n",
560 LCD_CMD_REG , LCD_DATA_REG);
561 led_func_ptr = led_LCD_driver;
562 led_type = LED_HASLCD;
563 break;
564
565 case DISPLAY_MODEL_LASI:
566 /* Skip to register LED in QEMU */
567 if (running_on_qemu)
568 return 1;
569 LED_DATA_REG = data_reg;
570 led_func_ptr = led_LASI_driver;
571 printk(KERN_INFO "LED display at %lx registered\n", LED_DATA_REG);
572 led_type = LED_NOLCD;
573 break;
574
575 case DISPLAY_MODEL_OLD_ASP:
576 LED_DATA_REG = data_reg;
577 led_func_ptr = led_ASP_driver;
578 printk(KERN_INFO "LED (ASP-style) display at %lx registered\n",
579 LED_DATA_REG);
580 led_type = LED_NOLCD;
581 break;
582
583 default:
584 printk(KERN_ERR "%s: Wrong LCD/LED model %d !\n",
585 __func__, lcd_info.model);
586 return 1;
587 }
588
589 /* mark the LCD/LED driver now as initialized and
590 * register to the reboot notifier chain */
591 initialized++;
592 register_reboot_notifier(&led_notifier);
593
594 /* Ensure the work is queued */
595 if (led_wq) {
596 queue_delayed_work(led_wq, &led_task, 0);
597 }
598
599 return 0;
600}
601
602/*
603 ** register_led_regions()
604 **
605 ** register_led_regions() registers the LCD/LED regions for /procfs.
606 ** At bootup - where the initialisation of the LCD/LED normally happens -
607 ** not all internal structures of request_region() are properly set up,
608 ** so that we delay the led-registration until after busdevices_init()
609 ** has been executed.
610 **
611 */
612
613void __init register_led_regions(void)
614{
615 switch (lcd_info.model) {
616 case DISPLAY_MODEL_LCD:
617 request_mem_region((unsigned long)LCD_CMD_REG, 1, "lcd_cmd");
618 request_mem_region((unsigned long)LCD_DATA_REG, 1, "lcd_data");
619 break;
620 case DISPLAY_MODEL_LASI:
621 case DISPLAY_MODEL_OLD_ASP:
622 request_mem_region((unsigned long)LED_DATA_REG, 1, "led_data");
623 break;
624 }
625}
626
627
628/*
629 **
630 ** lcd_print()
631 **
632 ** Displays the given string on the LCD-Display of newer machines.
633 ** lcd_print() disables/enables the timer-based led work queue to
634 ** avoid a race condition while writing the CMD/DATA register pair.
635 **
636 */
637int lcd_print( const char *str )
638{
639 int i;
640
641 if (!led_func_ptr || lcd_info.model != DISPLAY_MODEL_LCD)
642 return 0;
643
644 /* temporarily disable the led work task */
645 if (led_wq)
646 cancel_delayed_work_sync(&led_task);
647
648 /* copy display string to buffer for procfs */
649 strlcpy(lcd_text, str, sizeof(lcd_text));
650
651 /* Set LCD Cursor to 1st character */
652 gsc_writeb(lcd_info.reset_cmd1, LCD_CMD_REG);
653 udelay(lcd_info.min_cmd_delay);
654
655 /* Print the string */
656 for (i=0; i < lcd_info.lcd_width; i++) {
657 if (str && *str)
658 gsc_writeb(*str++, LCD_DATA_REG);
659 else
660 gsc_writeb(' ', LCD_DATA_REG);
661 udelay(lcd_info.min_cmd_delay);
662 }
663
664 /* re-queue the work */
665 if (led_wq) {
666 queue_delayed_work(led_wq, &led_task, 0);
667 }
668
669 return lcd_info.lcd_width;
670}
671
672/*
673 ** led_init()
674 **
675 ** led_init() is called very early in the bootup-process from setup.c
676 ** and asks the PDC for an usable chassis LCD or LED.
677 ** If the PDC doesn't return any info, then the LED
678 ** is detected by lasi.c or asp.c and registered with the
679 ** above functions lasi_led_init() or asp_led_init().
680 ** KittyHawk machines have often a buggy PDC, so that
681 ** we explicitly check for those machines here.
682 */
683
684int __init led_init(void)
685{
686 struct pdc_chassis_info chassis_info;
687 int ret;
688
689 snprintf(lcd_text_default, sizeof(lcd_text_default),
690 "Linux %s", init_utsname()->release);
691
692 /* Work around the buggy PDC of KittyHawk-machines */
693 switch (CPU_HVERSION) {
694 case 0x580: /* KittyHawk DC2-100 (K100) */
695 case 0x581: /* KittyHawk DC3-120 (K210) */
696 case 0x582: /* KittyHawk DC3 100 (K400) */
697 case 0x583: /* KittyHawk DC3 120 (K410) */
698 case 0x58B: /* KittyHawk DC2 100 (K200) */
699 printk(KERN_INFO "%s: KittyHawk-Machine (hversion 0x%x) found, "
700 "LED detection skipped.\n", __FILE__, CPU_HVERSION);
701 lcd_no_led_support = 1;
702 goto found; /* use the preinitialized values of lcd_info */
703 }
704
705 /* initialize the struct, so that we can check for valid return values */
706 lcd_info.model = DISPLAY_MODEL_NONE;
707 chassis_info.actcnt = chassis_info.maxcnt = 0;
708
709 ret = pdc_chassis_info(&chassis_info, &lcd_info, sizeof(lcd_info));
710 if (ret == PDC_OK) {
711 DPRINTK((KERN_INFO "%s: chassis info: model=%d (%s), "
712 "lcd_width=%d, cmd_delay=%u,\n"
713 "%s: sizecnt=%d, actcnt=%ld, maxcnt=%ld\n",
714 __FILE__, lcd_info.model,
715 (lcd_info.model==DISPLAY_MODEL_LCD) ? "LCD" :
716 (lcd_info.model==DISPLAY_MODEL_LASI) ? "LED" : "unknown",
717 lcd_info.lcd_width, lcd_info.min_cmd_delay,
718 __FILE__, sizeof(lcd_info),
719 chassis_info.actcnt, chassis_info.maxcnt));
720 DPRINTK((KERN_INFO "%s: cmd=%p, data=%p, reset1=%x, reset2=%x, act_enable=%d\n",
721 __FILE__, lcd_info.lcd_cmd_reg_addr,
722 lcd_info.lcd_data_reg_addr, lcd_info.reset_cmd1,
723 lcd_info.reset_cmd2, lcd_info.act_enable ));
724
725 /* check the results. Some machines have a buggy PDC */
726 if (chassis_info.actcnt <= 0 || chassis_info.actcnt != chassis_info.maxcnt)
727 goto not_found;
728
729 switch (lcd_info.model) {
730 case DISPLAY_MODEL_LCD: /* LCD display */
731 if (chassis_info.actcnt <
732 offsetof(struct pdc_chassis_lcd_info_ret_block, _pad)-1)
733 goto not_found;
734 if (!lcd_info.act_enable) {
735 DPRINTK((KERN_INFO "PDC prohibited usage of the LCD.\n"));
736 goto not_found;
737 }
738 break;
739
740 case DISPLAY_MODEL_NONE: /* no LED or LCD available */
741 printk(KERN_INFO "PDC reported no LCD or LED.\n");
742 goto not_found;
743
744 case DISPLAY_MODEL_LASI: /* Lasi style 8 bit LED display */
745 if (chassis_info.actcnt != 8 && chassis_info.actcnt != 32)
746 goto not_found;
747 break;
748
749 default:
750 printk(KERN_WARNING "PDC reported unknown LCD/LED model %d\n",
751 lcd_info.model);
752 goto not_found;
753 } /* switch() */
754
755found:
756 /* register the LCD/LED driver */
757 register_led_driver(lcd_info.model, LCD_CMD_REG, LCD_DATA_REG);
758 return 0;
759
760 } else { /* if() */
761 DPRINTK((KERN_INFO "pdc_chassis_info call failed with retval = %d\n", ret));
762 }
763
764not_found:
765 lcd_info.model = DISPLAY_MODEL_NONE;
766 return 1;
767}
768
769static void __exit led_exit(void)
770{
771 unregister_reboot_notifier(&led_notifier);
772 return;
773}
774
775#ifdef CONFIG_PROC_FS
776module_init(led_create_procfs)
777#endif