xref: /openbmc/linux/drivers/char/tlclk.c (revision e2c75e76)
1 /*
2  * Telecom Clock driver for Intel NetStructure(tm) MPCBL0010
3  *
4  * Copyright (C) 2005 Kontron Canada
5  *
6  * All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or (at
11  * your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
16  * NON INFRINGEMENT.  See the GNU General Public License for more
17  * details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  *
23  * Send feedback to <sebastien.bouchard@ca.kontron.com> and the current
24  * Maintainer  <mark.gross@intel.com>
25  *
26  * Description : This is the TELECOM CLOCK module driver for the ATCA
27  * MPCBL0010 ATCA computer.
28  */
29 
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/kernel.h>	/* printk() */
33 #include <linux/fs.h>		/* everything... */
34 #include <linux/errno.h>	/* error codes */
35 #include <linux/sched.h>
36 #include <linux/slab.h>
37 #include <linux/ioport.h>
38 #include <linux/interrupt.h>
39 #include <linux/spinlock.h>
40 #include <linux/mutex.h>
41 #include <linux/timer.h>
42 #include <linux/sysfs.h>
43 #include <linux/device.h>
44 #include <linux/miscdevice.h>
45 #include <linux/platform_device.h>
46 #include <asm/io.h>		/* inb/outb */
47 #include <linux/uaccess.h>
48 
49 MODULE_AUTHOR("Sebastien Bouchard <sebastien.bouchard@ca.kontron.com>");
50 MODULE_LICENSE("GPL");
51 
52 /*Hardware Reset of the PLL */
53 #define RESET_ON	0x00
54 #define RESET_OFF	0x01
55 
56 /* MODE SELECT */
57 #define NORMAL_MODE 	0x00
58 #define HOLDOVER_MODE	0x10
59 #define FREERUN_MODE	0x20
60 
61 /* FILTER SELECT */
62 #define FILTER_6HZ	0x04
63 #define FILTER_12HZ	0x00
64 
65 /* SELECT REFERENCE FREQUENCY */
66 #define REF_CLK1_8kHz		0x00
67 #define REF_CLK2_19_44MHz	0x02
68 
69 /* Select primary or secondary redundant clock */
70 #define PRIMARY_CLOCK	0x00
71 #define SECONDARY_CLOCK	0x01
72 
73 /* CLOCK TRANSMISSION DEFINE */
74 #define CLK_8kHz	0xff
75 #define CLK_16_384MHz	0xfb
76 
77 #define CLK_1_544MHz	0x00
78 #define CLK_2_048MHz	0x01
79 #define CLK_4_096MHz	0x02
80 #define CLK_6_312MHz	0x03
81 #define CLK_8_192MHz	0x04
82 #define CLK_19_440MHz	0x06
83 
84 #define CLK_8_592MHz	0x08
85 #define CLK_11_184MHz	0x09
86 #define CLK_34_368MHz	0x0b
87 #define CLK_44_736MHz	0x0a
88 
89 /* RECEIVED REFERENCE */
90 #define AMC_B1 0
91 #define AMC_B2 1
92 
93 /* HARDWARE SWITCHING DEFINE */
94 #define HW_ENABLE	0x80
95 #define HW_DISABLE	0x00
96 
97 /* HARDWARE SWITCHING MODE DEFINE */
98 #define PLL_HOLDOVER	0x40
99 #define LOST_CLOCK	0x00
100 
101 /* ALARMS DEFINE */
102 #define UNLOCK_MASK	0x10
103 #define HOLDOVER_MASK	0x20
104 #define SEC_LOST_MASK	0x40
105 #define PRI_LOST_MASK	0x80
106 
107 /* INTERRUPT CAUSE DEFINE */
108 
109 #define PRI_LOS_01_MASK		0x01
110 #define PRI_LOS_10_MASK		0x02
111 
112 #define SEC_LOS_01_MASK		0x04
113 #define SEC_LOS_10_MASK		0x08
114 
115 #define HOLDOVER_01_MASK	0x10
116 #define HOLDOVER_10_MASK	0x20
117 
118 #define UNLOCK_01_MASK		0x40
119 #define UNLOCK_10_MASK		0x80
120 
121 struct tlclk_alarms {
122 	__u32 lost_clocks;
123 	__u32 lost_primary_clock;
124 	__u32 lost_secondary_clock;
125 	__u32 primary_clock_back;
126 	__u32 secondary_clock_back;
127 	__u32 switchover_primary;
128 	__u32 switchover_secondary;
129 	__u32 pll_holdover;
130 	__u32 pll_end_holdover;
131 	__u32 pll_lost_sync;
132 	__u32 pll_sync;
133 };
134 /* Telecom clock I/O register definition */
135 #define TLCLK_BASE 0xa08
136 #define TLCLK_REG0 TLCLK_BASE
137 #define TLCLK_REG1 (TLCLK_BASE+1)
138 #define TLCLK_REG2 (TLCLK_BASE+2)
139 #define TLCLK_REG3 (TLCLK_BASE+3)
140 #define TLCLK_REG4 (TLCLK_BASE+4)
141 #define TLCLK_REG5 (TLCLK_BASE+5)
142 #define TLCLK_REG6 (TLCLK_BASE+6)
143 #define TLCLK_REG7 (TLCLK_BASE+7)
144 
145 #define SET_PORT_BITS(port, mask, val) outb(((inb(port) & mask) | val), port)
146 
147 /* 0 = Dynamic allocation of the major device number */
148 #define TLCLK_MAJOR 0
149 
150 /* sysfs interface definition:
151 Upon loading the driver will create a sysfs directory under
152 /sys/devices/platform/telco_clock.
153 
154 This directory exports the following interfaces.  There operation is
155 documented in the MCPBL0010 TPS under the Telecom Clock API section, 11.4.
156 alarms				:
157 current_ref			:
158 received_ref_clk3a		:
159 received_ref_clk3b		:
160 enable_clk3a_output		:
161 enable_clk3b_output		:
162 enable_clka0_output		:
163 enable_clka1_output		:
164 enable_clkb0_output		:
165 enable_clkb1_output		:
166 filter_select			:
167 hardware_switching		:
168 hardware_switching_mode		:
169 telclock_version		:
170 mode_select			:
171 refalign			:
172 reset				:
173 select_amcb1_transmit_clock	:
174 select_amcb2_transmit_clock	:
175 select_redundant_clock		:
176 select_ref_frequency		:
177 
178 All sysfs interfaces are integers in hex format, i.e echo 99 > refalign
179 has the same effect as echo 0x99 > refalign.
180 */
181 
182 static unsigned int telclk_interrupt;
183 
184 static int int_events;		/* Event that generate a interrupt */
185 static int got_event;		/* if events processing have been done */
186 
187 static void switchover_timeout(struct timer_list *t);
188 static struct timer_list switchover_timer;
189 static unsigned long tlclk_timer_data;
190 
191 static struct tlclk_alarms *alarm_events;
192 
193 static DEFINE_SPINLOCK(event_lock);
194 
195 static int tlclk_major = TLCLK_MAJOR;
196 
197 static irqreturn_t tlclk_interrupt(int irq, void *dev_id);
198 
199 static DECLARE_WAIT_QUEUE_HEAD(wq);
200 
201 static unsigned long useflags;
202 static DEFINE_MUTEX(tlclk_mutex);
203 
204 static int tlclk_open(struct inode *inode, struct file *filp)
205 {
206 	int result;
207 
208 	mutex_lock(&tlclk_mutex);
209 	if (test_and_set_bit(0, &useflags)) {
210 		result = -EBUSY;
211 		/* this legacy device is always one per system and it doesn't
212 		 * know how to handle multiple concurrent clients.
213 		 */
214 		goto out;
215 	}
216 
217 	/* Make sure there is no interrupt pending while
218 	 * initialising interrupt handler */
219 	inb(TLCLK_REG6);
220 
221 	/* This device is wired through the FPGA IO space of the ATCA blade
222 	 * we can't share this IRQ */
223 	result = request_irq(telclk_interrupt, &tlclk_interrupt,
224 			     0, "telco_clock", tlclk_interrupt);
225 	if (result == -EBUSY)
226 		printk(KERN_ERR "tlclk: Interrupt can't be reserved.\n");
227 	else
228 		inb(TLCLK_REG6);	/* Clear interrupt events */
229 
230 out:
231 	mutex_unlock(&tlclk_mutex);
232 	return result;
233 }
234 
235 static int tlclk_release(struct inode *inode, struct file *filp)
236 {
237 	free_irq(telclk_interrupt, tlclk_interrupt);
238 	clear_bit(0, &useflags);
239 
240 	return 0;
241 }
242 
243 static ssize_t tlclk_read(struct file *filp, char __user *buf, size_t count,
244 		loff_t *f_pos)
245 {
246 	if (count < sizeof(struct tlclk_alarms))
247 		return -EIO;
248 	if (mutex_lock_interruptible(&tlclk_mutex))
249 		return -EINTR;
250 
251 
252 	wait_event_interruptible(wq, got_event);
253 	if (copy_to_user(buf, alarm_events, sizeof(struct tlclk_alarms))) {
254 		mutex_unlock(&tlclk_mutex);
255 		return -EFAULT;
256 	}
257 
258 	memset(alarm_events, 0, sizeof(struct tlclk_alarms));
259 	got_event = 0;
260 
261 	mutex_unlock(&tlclk_mutex);
262 	return  sizeof(struct tlclk_alarms);
263 }
264 
265 static const struct file_operations tlclk_fops = {
266 	.read = tlclk_read,
267 	.open = tlclk_open,
268 	.release = tlclk_release,
269 	.llseek = noop_llseek,
270 
271 };
272 
273 static struct miscdevice tlclk_miscdev = {
274 	.minor = MISC_DYNAMIC_MINOR,
275 	.name = "telco_clock",
276 	.fops = &tlclk_fops,
277 };
278 
279 static ssize_t show_current_ref(struct device *d,
280 		struct device_attribute *attr, char *buf)
281 {
282 	unsigned long ret_val;
283 	unsigned long flags;
284 
285 	spin_lock_irqsave(&event_lock, flags);
286 	ret_val = ((inb(TLCLK_REG1) & 0x08) >> 3);
287 	spin_unlock_irqrestore(&event_lock, flags);
288 
289 	return sprintf(buf, "0x%lX\n", ret_val);
290 }
291 
292 static DEVICE_ATTR(current_ref, S_IRUGO, show_current_ref, NULL);
293 
294 
295 static ssize_t show_telclock_version(struct device *d,
296 		struct device_attribute *attr, char *buf)
297 {
298 	unsigned long ret_val;
299 	unsigned long flags;
300 
301 	spin_lock_irqsave(&event_lock, flags);
302 	ret_val = inb(TLCLK_REG5);
303 	spin_unlock_irqrestore(&event_lock, flags);
304 
305 	return sprintf(buf, "0x%lX\n", ret_val);
306 }
307 
308 static DEVICE_ATTR(telclock_version, S_IRUGO,
309 		show_telclock_version, NULL);
310 
311 static ssize_t show_alarms(struct device *d,
312 		struct device_attribute *attr,  char *buf)
313 {
314 	unsigned long ret_val;
315 	unsigned long flags;
316 
317 	spin_lock_irqsave(&event_lock, flags);
318 	ret_val = (inb(TLCLK_REG2) & 0xf0);
319 	spin_unlock_irqrestore(&event_lock, flags);
320 
321 	return sprintf(buf, "0x%lX\n", ret_val);
322 }
323 
324 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
325 
326 static ssize_t store_received_ref_clk3a(struct device *d,
327 		 struct device_attribute *attr, const char *buf, size_t count)
328 {
329 	unsigned long tmp;
330 	unsigned char val;
331 	unsigned long flags;
332 
333 	sscanf(buf, "%lX", &tmp);
334 	dev_dbg(d, ": tmp = 0x%lX\n", tmp);
335 
336 	val = (unsigned char)tmp;
337 	spin_lock_irqsave(&event_lock, flags);
338 	SET_PORT_BITS(TLCLK_REG1, 0xef, val);
339 	spin_unlock_irqrestore(&event_lock, flags);
340 
341 	return strnlen(buf, count);
342 }
343 
344 static DEVICE_ATTR(received_ref_clk3a, (S_IWUSR|S_IWGRP), NULL,
345 		store_received_ref_clk3a);
346 
347 
348 static ssize_t store_received_ref_clk3b(struct device *d,
349 		 struct device_attribute *attr, const char *buf, size_t count)
350 {
351 	unsigned long tmp;
352 	unsigned char val;
353 	unsigned long flags;
354 
355 	sscanf(buf, "%lX", &tmp);
356 	dev_dbg(d, ": tmp = 0x%lX\n", tmp);
357 
358 	val = (unsigned char)tmp;
359 	spin_lock_irqsave(&event_lock, flags);
360 	SET_PORT_BITS(TLCLK_REG1, 0xdf, val << 1);
361 	spin_unlock_irqrestore(&event_lock, flags);
362 
363 	return strnlen(buf, count);
364 }
365 
366 static DEVICE_ATTR(received_ref_clk3b, (S_IWUSR|S_IWGRP), NULL,
367 		store_received_ref_clk3b);
368 
369 
370 static ssize_t store_enable_clk3b_output(struct device *d,
371 		 struct device_attribute *attr, const char *buf, size_t count)
372 {
373 	unsigned long tmp;
374 	unsigned char val;
375 	unsigned long flags;
376 
377 	sscanf(buf, "%lX", &tmp);
378 	dev_dbg(d, ": tmp = 0x%lX\n", tmp);
379 
380 	val = (unsigned char)tmp;
381 	spin_lock_irqsave(&event_lock, flags);
382 	SET_PORT_BITS(TLCLK_REG3, 0x7f, val << 7);
383 	spin_unlock_irqrestore(&event_lock, flags);
384 
385 	return strnlen(buf, count);
386 }
387 
388 static DEVICE_ATTR(enable_clk3b_output, (S_IWUSR|S_IWGRP), NULL,
389 		store_enable_clk3b_output);
390 
391 static ssize_t store_enable_clk3a_output(struct device *d,
392 		 struct device_attribute *attr, const char *buf, size_t count)
393 {
394 	unsigned long flags;
395 	unsigned long tmp;
396 	unsigned char val;
397 
398 	sscanf(buf, "%lX", &tmp);
399 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
400 
401 	val = (unsigned char)tmp;
402 	spin_lock_irqsave(&event_lock, flags);
403 	SET_PORT_BITS(TLCLK_REG3, 0xbf, val << 6);
404 	spin_unlock_irqrestore(&event_lock, flags);
405 
406 	return strnlen(buf, count);
407 }
408 
409 static DEVICE_ATTR(enable_clk3a_output, (S_IWUSR|S_IWGRP), NULL,
410 		store_enable_clk3a_output);
411 
412 static ssize_t store_enable_clkb1_output(struct device *d,
413 		 struct device_attribute *attr, const char *buf, size_t count)
414 {
415 	unsigned long flags;
416 	unsigned long tmp;
417 	unsigned char val;
418 
419 	sscanf(buf, "%lX", &tmp);
420 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
421 
422 	val = (unsigned char)tmp;
423 	spin_lock_irqsave(&event_lock, flags);
424 	SET_PORT_BITS(TLCLK_REG2, 0xf7, val << 3);
425 	spin_unlock_irqrestore(&event_lock, flags);
426 
427 	return strnlen(buf, count);
428 }
429 
430 static DEVICE_ATTR(enable_clkb1_output, (S_IWUSR|S_IWGRP), NULL,
431 		store_enable_clkb1_output);
432 
433 
434 static ssize_t store_enable_clka1_output(struct device *d,
435 		 struct device_attribute *attr, const char *buf, size_t count)
436 {
437 	unsigned long flags;
438 	unsigned long tmp;
439 	unsigned char val;
440 
441 	sscanf(buf, "%lX", &tmp);
442 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
443 
444 	val = (unsigned char)tmp;
445 	spin_lock_irqsave(&event_lock, flags);
446 	SET_PORT_BITS(TLCLK_REG2, 0xfb, val << 2);
447 	spin_unlock_irqrestore(&event_lock, flags);
448 
449 	return strnlen(buf, count);
450 }
451 
452 static DEVICE_ATTR(enable_clka1_output, (S_IWUSR|S_IWGRP), NULL,
453 		store_enable_clka1_output);
454 
455 static ssize_t store_enable_clkb0_output(struct device *d,
456 		 struct device_attribute *attr, const char *buf, size_t count)
457 {
458 	unsigned long flags;
459 	unsigned long tmp;
460 	unsigned char val;
461 
462 	sscanf(buf, "%lX", &tmp);
463 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
464 
465 	val = (unsigned char)tmp;
466 	spin_lock_irqsave(&event_lock, flags);
467 	SET_PORT_BITS(TLCLK_REG2, 0xfd, val << 1);
468 	spin_unlock_irqrestore(&event_lock, flags);
469 
470 	return strnlen(buf, count);
471 }
472 
473 static DEVICE_ATTR(enable_clkb0_output, (S_IWUSR|S_IWGRP), NULL,
474 		store_enable_clkb0_output);
475 
476 static ssize_t store_enable_clka0_output(struct device *d,
477 		 struct device_attribute *attr, const char *buf, size_t count)
478 {
479 	unsigned long flags;
480 	unsigned long tmp;
481 	unsigned char val;
482 
483 	sscanf(buf, "%lX", &tmp);
484 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
485 
486 	val = (unsigned char)tmp;
487 	spin_lock_irqsave(&event_lock, flags);
488 	SET_PORT_BITS(TLCLK_REG2, 0xfe, val);
489 	spin_unlock_irqrestore(&event_lock, flags);
490 
491 	return strnlen(buf, count);
492 }
493 
494 static DEVICE_ATTR(enable_clka0_output, (S_IWUSR|S_IWGRP), NULL,
495 		store_enable_clka0_output);
496 
497 static ssize_t store_select_amcb2_transmit_clock(struct device *d,
498 		struct device_attribute *attr, const char *buf, size_t count)
499 {
500 	unsigned long flags;
501 	unsigned long tmp;
502 	unsigned char val;
503 
504 	sscanf(buf, "%lX", &tmp);
505 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
506 
507 	val = (unsigned char)tmp;
508 	spin_lock_irqsave(&event_lock, flags);
509 		if ((val == CLK_8kHz) || (val == CLK_16_384MHz)) {
510 			SET_PORT_BITS(TLCLK_REG3, 0xc7, 0x28);
511 			SET_PORT_BITS(TLCLK_REG1, 0xfb, ~val);
512 		} else if (val >= CLK_8_592MHz) {
513 			SET_PORT_BITS(TLCLK_REG3, 0xc7, 0x38);
514 			switch (val) {
515 			case CLK_8_592MHz:
516 				SET_PORT_BITS(TLCLK_REG0, 0xfc, 2);
517 				break;
518 			case CLK_11_184MHz:
519 				SET_PORT_BITS(TLCLK_REG0, 0xfc, 0);
520 				break;
521 			case CLK_34_368MHz:
522 				SET_PORT_BITS(TLCLK_REG0, 0xfc, 3);
523 				break;
524 			case CLK_44_736MHz:
525 				SET_PORT_BITS(TLCLK_REG0, 0xfc, 1);
526 				break;
527 			}
528 		} else
529 			SET_PORT_BITS(TLCLK_REG3, 0xc7, val << 3);
530 
531 	spin_unlock_irqrestore(&event_lock, flags);
532 
533 	return strnlen(buf, count);
534 }
535 
536 static DEVICE_ATTR(select_amcb2_transmit_clock, (S_IWUSR|S_IWGRP), NULL,
537 	store_select_amcb2_transmit_clock);
538 
539 static ssize_t store_select_amcb1_transmit_clock(struct device *d,
540 		 struct device_attribute *attr, const char *buf, size_t count)
541 {
542 	unsigned long tmp;
543 	unsigned char val;
544 	unsigned long flags;
545 
546 	sscanf(buf, "%lX", &tmp);
547 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
548 
549 	val = (unsigned char)tmp;
550 	spin_lock_irqsave(&event_lock, flags);
551 		if ((val == CLK_8kHz) || (val == CLK_16_384MHz)) {
552 			SET_PORT_BITS(TLCLK_REG3, 0xf8, 0x5);
553 			SET_PORT_BITS(TLCLK_REG1, 0xfb, ~val);
554 		} else if (val >= CLK_8_592MHz) {
555 			SET_PORT_BITS(TLCLK_REG3, 0xf8, 0x7);
556 			switch (val) {
557 			case CLK_8_592MHz:
558 				SET_PORT_BITS(TLCLK_REG0, 0xfc, 2);
559 				break;
560 			case CLK_11_184MHz:
561 				SET_PORT_BITS(TLCLK_REG0, 0xfc, 0);
562 				break;
563 			case CLK_34_368MHz:
564 				SET_PORT_BITS(TLCLK_REG0, 0xfc, 3);
565 				break;
566 			case CLK_44_736MHz:
567 				SET_PORT_BITS(TLCLK_REG0, 0xfc, 1);
568 				break;
569 			}
570 		} else
571 			SET_PORT_BITS(TLCLK_REG3, 0xf8, val);
572 	spin_unlock_irqrestore(&event_lock, flags);
573 
574 	return strnlen(buf, count);
575 }
576 
577 static DEVICE_ATTR(select_amcb1_transmit_clock, (S_IWUSR|S_IWGRP), NULL,
578 		store_select_amcb1_transmit_clock);
579 
580 static ssize_t store_select_redundant_clock(struct device *d,
581 		 struct device_attribute *attr, const char *buf, size_t count)
582 {
583 	unsigned long tmp;
584 	unsigned char val;
585 	unsigned long flags;
586 
587 	sscanf(buf, "%lX", &tmp);
588 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
589 
590 	val = (unsigned char)tmp;
591 	spin_lock_irqsave(&event_lock, flags);
592 	SET_PORT_BITS(TLCLK_REG1, 0xfe, val);
593 	spin_unlock_irqrestore(&event_lock, flags);
594 
595 	return strnlen(buf, count);
596 }
597 
598 static DEVICE_ATTR(select_redundant_clock, (S_IWUSR|S_IWGRP), NULL,
599 		store_select_redundant_clock);
600 
601 static ssize_t store_select_ref_frequency(struct device *d,
602 		 struct device_attribute *attr, const char *buf, size_t count)
603 {
604 	unsigned long tmp;
605 	unsigned char val;
606 	unsigned long flags;
607 
608 	sscanf(buf, "%lX", &tmp);
609 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
610 
611 	val = (unsigned char)tmp;
612 	spin_lock_irqsave(&event_lock, flags);
613 	SET_PORT_BITS(TLCLK_REG1, 0xfd, val);
614 	spin_unlock_irqrestore(&event_lock, flags);
615 
616 	return strnlen(buf, count);
617 }
618 
619 static DEVICE_ATTR(select_ref_frequency, (S_IWUSR|S_IWGRP), NULL,
620 		store_select_ref_frequency);
621 
622 static ssize_t store_filter_select(struct device *d,
623 		 struct device_attribute *attr, const char *buf, size_t count)
624 {
625 	unsigned long tmp;
626 	unsigned char val;
627 	unsigned long flags;
628 
629 	sscanf(buf, "%lX", &tmp);
630 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
631 
632 	val = (unsigned char)tmp;
633 	spin_lock_irqsave(&event_lock, flags);
634 	SET_PORT_BITS(TLCLK_REG0, 0xfb, val);
635 	spin_unlock_irqrestore(&event_lock, flags);
636 
637 	return strnlen(buf, count);
638 }
639 
640 static DEVICE_ATTR(filter_select, (S_IWUSR|S_IWGRP), NULL, store_filter_select);
641 
642 static ssize_t store_hardware_switching_mode(struct device *d,
643 		 struct device_attribute *attr, const char *buf, size_t count)
644 {
645 	unsigned long tmp;
646 	unsigned char val;
647 	unsigned long flags;
648 
649 	sscanf(buf, "%lX", &tmp);
650 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
651 
652 	val = (unsigned char)tmp;
653 	spin_lock_irqsave(&event_lock, flags);
654 	SET_PORT_BITS(TLCLK_REG0, 0xbf, val);
655 	spin_unlock_irqrestore(&event_lock, flags);
656 
657 	return strnlen(buf, count);
658 }
659 
660 static DEVICE_ATTR(hardware_switching_mode, (S_IWUSR|S_IWGRP), NULL,
661 		store_hardware_switching_mode);
662 
663 static ssize_t store_hardware_switching(struct device *d,
664 		 struct device_attribute *attr, const char *buf, size_t count)
665 {
666 	unsigned long tmp;
667 	unsigned char val;
668 	unsigned long flags;
669 
670 	sscanf(buf, "%lX", &tmp);
671 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
672 
673 	val = (unsigned char)tmp;
674 	spin_lock_irqsave(&event_lock, flags);
675 	SET_PORT_BITS(TLCLK_REG0, 0x7f, val);
676 	spin_unlock_irqrestore(&event_lock, flags);
677 
678 	return strnlen(buf, count);
679 }
680 
681 static DEVICE_ATTR(hardware_switching, (S_IWUSR|S_IWGRP), NULL,
682 		store_hardware_switching);
683 
684 static ssize_t store_refalign (struct device *d,
685 		 struct device_attribute *attr, const char *buf, size_t count)
686 {
687 	unsigned long tmp;
688 	unsigned long flags;
689 
690 	sscanf(buf, "%lX", &tmp);
691 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
692 	spin_lock_irqsave(&event_lock, flags);
693 	SET_PORT_BITS(TLCLK_REG0, 0xf7, 0);
694 	SET_PORT_BITS(TLCLK_REG0, 0xf7, 0x08);
695 	SET_PORT_BITS(TLCLK_REG0, 0xf7, 0);
696 	spin_unlock_irqrestore(&event_lock, flags);
697 
698 	return strnlen(buf, count);
699 }
700 
701 static DEVICE_ATTR(refalign, (S_IWUSR|S_IWGRP), NULL, store_refalign);
702 
703 static ssize_t store_mode_select (struct device *d,
704 		 struct device_attribute *attr, const char *buf, size_t count)
705 {
706 	unsigned long tmp;
707 	unsigned char val;
708 	unsigned long flags;
709 
710 	sscanf(buf, "%lX", &tmp);
711 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
712 
713 	val = (unsigned char)tmp;
714 	spin_lock_irqsave(&event_lock, flags);
715 	SET_PORT_BITS(TLCLK_REG0, 0xcf, val);
716 	spin_unlock_irqrestore(&event_lock, flags);
717 
718 	return strnlen(buf, count);
719 }
720 
721 static DEVICE_ATTR(mode_select, (S_IWUSR|S_IWGRP), NULL, store_mode_select);
722 
723 static ssize_t store_reset (struct device *d,
724 		 struct device_attribute *attr, const char *buf, size_t count)
725 {
726 	unsigned long tmp;
727 	unsigned char val;
728 	unsigned long flags;
729 
730 	sscanf(buf, "%lX", &tmp);
731 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
732 
733 	val = (unsigned char)tmp;
734 	spin_lock_irqsave(&event_lock, flags);
735 	SET_PORT_BITS(TLCLK_REG4, 0xfd, val);
736 	spin_unlock_irqrestore(&event_lock, flags);
737 
738 	return strnlen(buf, count);
739 }
740 
741 static DEVICE_ATTR(reset, (S_IWUSR|S_IWGRP), NULL, store_reset);
742 
743 static struct attribute *tlclk_sysfs_entries[] = {
744 	&dev_attr_current_ref.attr,
745 	&dev_attr_telclock_version.attr,
746 	&dev_attr_alarms.attr,
747 	&dev_attr_received_ref_clk3a.attr,
748 	&dev_attr_received_ref_clk3b.attr,
749 	&dev_attr_enable_clk3a_output.attr,
750 	&dev_attr_enable_clk3b_output.attr,
751 	&dev_attr_enable_clkb1_output.attr,
752 	&dev_attr_enable_clka1_output.attr,
753 	&dev_attr_enable_clkb0_output.attr,
754 	&dev_attr_enable_clka0_output.attr,
755 	&dev_attr_select_amcb1_transmit_clock.attr,
756 	&dev_attr_select_amcb2_transmit_clock.attr,
757 	&dev_attr_select_redundant_clock.attr,
758 	&dev_attr_select_ref_frequency.attr,
759 	&dev_attr_filter_select.attr,
760 	&dev_attr_hardware_switching_mode.attr,
761 	&dev_attr_hardware_switching.attr,
762 	&dev_attr_refalign.attr,
763 	&dev_attr_mode_select.attr,
764 	&dev_attr_reset.attr,
765 	NULL
766 };
767 
768 static const struct attribute_group tlclk_attribute_group = {
769 	.name = NULL,		/* put in device directory */
770 	.attrs = tlclk_sysfs_entries,
771 };
772 
773 static struct platform_device *tlclk_device;
774 
775 static int __init tlclk_init(void)
776 {
777 	int ret;
778 
779 	ret = register_chrdev(tlclk_major, "telco_clock", &tlclk_fops);
780 	if (ret < 0) {
781 		printk(KERN_ERR "tlclk: can't get major %d.\n", tlclk_major);
782 		return ret;
783 	}
784 	tlclk_major = ret;
785 	alarm_events = kzalloc( sizeof(struct tlclk_alarms), GFP_KERNEL);
786 	if (!alarm_events) {
787 		ret = -ENOMEM;
788 		goto out1;
789 	}
790 
791 	/* Read telecom clock IRQ number (Set by BIOS) */
792 	if (!request_region(TLCLK_BASE, 8, "telco_clock")) {
793 		printk(KERN_ERR "tlclk: request_region 0x%X failed.\n",
794 			TLCLK_BASE);
795 		ret = -EBUSY;
796 		goto out2;
797 	}
798 	telclk_interrupt = (inb(TLCLK_REG7) & 0x0f);
799 
800 	if (0x0F == telclk_interrupt ) { /* not MCPBL0010 ? */
801 		printk(KERN_ERR "telclk_interrupt = 0x%x non-mcpbl0010 hw.\n",
802 			telclk_interrupt);
803 		ret = -ENXIO;
804 		goto out3;
805 	}
806 
807 	timer_setup(&switchover_timer, switchover_timeout, 0);
808 
809 	ret = misc_register(&tlclk_miscdev);
810 	if (ret < 0) {
811 		printk(KERN_ERR "tlclk: misc_register returns %d.\n", ret);
812 		goto out3;
813 	}
814 
815 	tlclk_device = platform_device_register_simple("telco_clock",
816 				-1, NULL, 0);
817 	if (IS_ERR(tlclk_device)) {
818 		printk(KERN_ERR "tlclk: platform_device_register failed.\n");
819 		ret = PTR_ERR(tlclk_device);
820 		goto out4;
821 	}
822 
823 	ret = sysfs_create_group(&tlclk_device->dev.kobj,
824 			&tlclk_attribute_group);
825 	if (ret) {
826 		printk(KERN_ERR "tlclk: failed to create sysfs device attributes.\n");
827 		goto out5;
828 	}
829 
830 	return 0;
831 out5:
832 	platform_device_unregister(tlclk_device);
833 out4:
834 	misc_deregister(&tlclk_miscdev);
835 out3:
836 	release_region(TLCLK_BASE, 8);
837 out2:
838 	kfree(alarm_events);
839 out1:
840 	unregister_chrdev(tlclk_major, "telco_clock");
841 	return ret;
842 }
843 
844 static void __exit tlclk_cleanup(void)
845 {
846 	sysfs_remove_group(&tlclk_device->dev.kobj, &tlclk_attribute_group);
847 	platform_device_unregister(tlclk_device);
848 	misc_deregister(&tlclk_miscdev);
849 	unregister_chrdev(tlclk_major, "telco_clock");
850 
851 	release_region(TLCLK_BASE, 8);
852 	del_timer_sync(&switchover_timer);
853 	kfree(alarm_events);
854 
855 }
856 
857 static void switchover_timeout(struct timer_list *unused)
858 {
859 	unsigned long flags = tlclk_timer_data;
860 
861 	if ((flags & 1)) {
862 		if ((inb(TLCLK_REG1) & 0x08) != (flags & 0x08))
863 			alarm_events->switchover_primary++;
864 	} else {
865 		if ((inb(TLCLK_REG1) & 0x08) != (flags & 0x08))
866 			alarm_events->switchover_secondary++;
867 	}
868 
869 	/* Alarm processing is done, wake up read task */
870 	del_timer(&switchover_timer);
871 	got_event = 1;
872 	wake_up(&wq);
873 }
874 
875 static irqreturn_t tlclk_interrupt(int irq, void *dev_id)
876 {
877 	unsigned long flags;
878 
879 	spin_lock_irqsave(&event_lock, flags);
880 	/* Read and clear interrupt events */
881 	int_events = inb(TLCLK_REG6);
882 
883 	/* Primary_Los changed from 0 to 1 ? */
884 	if (int_events & PRI_LOS_01_MASK) {
885 		if (inb(TLCLK_REG2) & SEC_LOST_MASK)
886 			alarm_events->lost_clocks++;
887 		else
888 			alarm_events->lost_primary_clock++;
889 	}
890 
891 	/* Primary_Los changed from 1 to 0 ? */
892 	if (int_events & PRI_LOS_10_MASK) {
893 		alarm_events->primary_clock_back++;
894 		SET_PORT_BITS(TLCLK_REG1, 0xFE, 1);
895 	}
896 	/* Secondary_Los changed from 0 to 1 ? */
897 	if (int_events & SEC_LOS_01_MASK) {
898 		if (inb(TLCLK_REG2) & PRI_LOST_MASK)
899 			alarm_events->lost_clocks++;
900 		else
901 			alarm_events->lost_secondary_clock++;
902 	}
903 	/* Secondary_Los changed from 1 to 0 ? */
904 	if (int_events & SEC_LOS_10_MASK) {
905 		alarm_events->secondary_clock_back++;
906 		SET_PORT_BITS(TLCLK_REG1, 0xFE, 0);
907 	}
908 	if (int_events & HOLDOVER_10_MASK)
909 		alarm_events->pll_end_holdover++;
910 
911 	if (int_events & UNLOCK_01_MASK)
912 		alarm_events->pll_lost_sync++;
913 
914 	if (int_events & UNLOCK_10_MASK)
915 		alarm_events->pll_sync++;
916 
917 	/* Holdover changed from 0 to 1 ? */
918 	if (int_events & HOLDOVER_01_MASK) {
919 		alarm_events->pll_holdover++;
920 
921 		/* TIMEOUT in ~10ms */
922 		switchover_timer.expires = jiffies + msecs_to_jiffies(10);
923 		tlclk_timer_data = inb(TLCLK_REG1);
924 		mod_timer(&switchover_timer, switchover_timer.expires);
925 	} else {
926 		got_event = 1;
927 		wake_up(&wq);
928 	}
929 	spin_unlock_irqrestore(&event_lock, flags);
930 
931 	return IRQ_HANDLED;
932 }
933 
934 module_init(tlclk_init);
935 module_exit(tlclk_cleanup);
936