xref: /linux/drivers/char/tlclk.c (revision f879306834818ebd1722a4372079610cdd466fec)
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_DESCRIPTION("Telecom Clock driver for Intel NetStructure(tm) MPCBL0010");
51 MODULE_LICENSE("GPL");
52 
53 /*Hardware Reset of the PLL */
54 #define RESET_ON	0x00
55 #define RESET_OFF	0x01
56 
57 /* MODE SELECT */
58 #define NORMAL_MODE 	0x00
59 #define HOLDOVER_MODE	0x10
60 #define FREERUN_MODE	0x20
61 
62 /* FILTER SELECT */
63 #define FILTER_6HZ	0x04
64 #define FILTER_12HZ	0x00
65 
66 /* SELECT REFERENCE FREQUENCY */
67 #define REF_CLK1_8kHz		0x00
68 #define REF_CLK2_19_44MHz	0x02
69 
70 /* Select primary or secondary redundant clock */
71 #define PRIMARY_CLOCK	0x00
72 #define SECONDARY_CLOCK	0x01
73 
74 /* CLOCK TRANSMISSION DEFINE */
75 #define CLK_8kHz	0xff
76 #define CLK_16_384MHz	0xfb
77 
78 #define CLK_1_544MHz	0x00
79 #define CLK_2_048MHz	0x01
80 #define CLK_4_096MHz	0x02
81 #define CLK_6_312MHz	0x03
82 #define CLK_8_192MHz	0x04
83 #define CLK_19_440MHz	0x06
84 
85 #define CLK_8_592MHz	0x08
86 #define CLK_11_184MHz	0x09
87 #define CLK_34_368MHz	0x0b
88 #define CLK_44_736MHz	0x0a
89 
90 /* RECEIVED REFERENCE */
91 #define AMC_B1 0
92 #define AMC_B2 1
93 
94 /* HARDWARE SWITCHING DEFINE */
95 #define HW_ENABLE	0x80
96 #define HW_DISABLE	0x00
97 
98 /* HARDWARE SWITCHING MODE DEFINE */
99 #define PLL_HOLDOVER	0x40
100 #define LOST_CLOCK	0x00
101 
102 /* ALARMS DEFINE */
103 #define UNLOCK_MASK	0x10
104 #define HOLDOVER_MASK	0x20
105 #define SEC_LOST_MASK	0x40
106 #define PRI_LOST_MASK	0x80
107 
108 /* INTERRUPT CAUSE DEFINE */
109 
110 #define PRI_LOS_01_MASK		0x01
111 #define PRI_LOS_10_MASK		0x02
112 
113 #define SEC_LOS_01_MASK		0x04
114 #define SEC_LOS_10_MASK		0x08
115 
116 #define HOLDOVER_01_MASK	0x10
117 #define HOLDOVER_10_MASK	0x20
118 
119 #define UNLOCK_01_MASK		0x40
120 #define UNLOCK_10_MASK		0x80
121 
122 struct tlclk_alarms {
123 	__u32 lost_clocks;
124 	__u32 lost_primary_clock;
125 	__u32 lost_secondary_clock;
126 	__u32 primary_clock_back;
127 	__u32 secondary_clock_back;
128 	__u32 switchover_primary;
129 	__u32 switchover_secondary;
130 	__u32 pll_holdover;
131 	__u32 pll_end_holdover;
132 	__u32 pll_lost_sync;
133 	__u32 pll_sync;
134 };
135 /* Telecom clock I/O register definition */
136 #define TLCLK_BASE 0xa08
137 #define TLCLK_REG0 TLCLK_BASE
138 #define TLCLK_REG1 (TLCLK_BASE+1)
139 #define TLCLK_REG2 (TLCLK_BASE+2)
140 #define TLCLK_REG3 (TLCLK_BASE+3)
141 #define TLCLK_REG4 (TLCLK_BASE+4)
142 #define TLCLK_REG5 (TLCLK_BASE+5)
143 #define TLCLK_REG6 (TLCLK_BASE+6)
144 #define TLCLK_REG7 (TLCLK_BASE+7)
145 
146 #define SET_PORT_BITS(port, mask, val) outb(((inb(port) & mask) | val), port)
147 
148 /* 0 = Dynamic allocation of the major device number */
149 #define TLCLK_MAJOR 0
150 
151 /* sysfs interface definition:
152 Upon loading the driver will create a sysfs directory under
153 /sys/devices/platform/telco_clock.
154 
155 This directory exports the following interfaces.  There operation is
156 documented in the MCPBL0010 TPS under the Telecom Clock API section, 11.4.
157 alarms				:
158 current_ref			:
159 received_ref_clk3a		:
160 received_ref_clk3b		:
161 enable_clk3a_output		:
162 enable_clk3b_output		:
163 enable_clka0_output		:
164 enable_clka1_output		:
165 enable_clkb0_output		:
166 enable_clkb1_output		:
167 filter_select			:
168 hardware_switching		:
169 hardware_switching_mode		:
170 telclock_version		:
171 mode_select			:
172 refalign			:
173 reset				:
174 select_amcb1_transmit_clock	:
175 select_amcb2_transmit_clock	:
176 select_redundant_clock		:
177 select_ref_frequency		:
178 
179 All sysfs interfaces are integers in hex format, i.e echo 99 > refalign
180 has the same effect as echo 0x99 > refalign.
181 */
182 
183 static unsigned int telclk_interrupt;
184 
185 static int int_events;		/* Event that generate a interrupt */
186 static int got_event;		/* if events processing have been done */
187 
188 static void switchover_timeout(struct timer_list *t);
189 static struct timer_list switchover_timer;
190 static unsigned long tlclk_timer_data;
191 
192 static struct tlclk_alarms *alarm_events;
193 
194 static DEFINE_SPINLOCK(event_lock);
195 
196 static int tlclk_major = TLCLK_MAJOR;
197 
198 static irqreturn_t tlclk_interrupt(int irq, void *dev_id);
199 
200 static DECLARE_WAIT_QUEUE_HEAD(wq);
201 
202 static unsigned long useflags;
203 static DEFINE_MUTEX(tlclk_mutex);
204 
205 static int tlclk_open(struct inode *inode, struct file *filp)
206 {
207 	int result;
208 
209 	mutex_lock(&tlclk_mutex);
210 	if (test_and_set_bit(0, &useflags)) {
211 		result = -EBUSY;
212 		/* this legacy device is always one per system and it doesn't
213 		 * know how to handle multiple concurrent clients.
214 		 */
215 		goto out;
216 	}
217 
218 	/* Make sure there is no interrupt pending while
219 	 * initialising interrupt handler */
220 	inb(TLCLK_REG6);
221 
222 	/* This device is wired through the FPGA IO space of the ATCA blade
223 	 * we can't share this IRQ */
224 	result = request_irq(telclk_interrupt, &tlclk_interrupt,
225 			     0, "telco_clock", tlclk_interrupt);
226 	if (result == -EBUSY)
227 		printk(KERN_ERR "tlclk: Interrupt can't be reserved.\n");
228 	else
229 		inb(TLCLK_REG6);	/* Clear interrupt events */
230 
231 out:
232 	mutex_unlock(&tlclk_mutex);
233 	return result;
234 }
235 
236 static int tlclk_release(struct inode *inode, struct file *filp)
237 {
238 	free_irq(telclk_interrupt, tlclk_interrupt);
239 	clear_bit(0, &useflags);
240 
241 	return 0;
242 }
243 
244 static ssize_t tlclk_read(struct file *filp, char __user *buf, size_t count,
245 		loff_t *f_pos)
246 {
247 	if (count < sizeof(struct tlclk_alarms))
248 		return -EIO;
249 	if (mutex_lock_interruptible(&tlclk_mutex))
250 		return -EINTR;
251 
252 
253 	wait_event_interruptible(wq, got_event);
254 	if (copy_to_user(buf, alarm_events, sizeof(struct tlclk_alarms))) {
255 		mutex_unlock(&tlclk_mutex);
256 		return -EFAULT;
257 	}
258 
259 	memset(alarm_events, 0, sizeof(struct tlclk_alarms));
260 	got_event = 0;
261 
262 	mutex_unlock(&tlclk_mutex);
263 	return  sizeof(struct tlclk_alarms);
264 }
265 
266 static const struct file_operations tlclk_fops = {
267 	.read = tlclk_read,
268 	.open = tlclk_open,
269 	.release = tlclk_release,
270 	.llseek = noop_llseek,
271 
272 };
273 
274 static struct miscdevice tlclk_miscdev = {
275 	.minor = MISC_DYNAMIC_MINOR,
276 	.name = "telco_clock",
277 	.fops = &tlclk_fops,
278 };
279 
280 static ssize_t show_current_ref(struct device *d,
281 		struct device_attribute *attr, char *buf)
282 {
283 	unsigned long ret_val;
284 	unsigned long flags;
285 
286 	spin_lock_irqsave(&event_lock, flags);
287 	ret_val = ((inb(TLCLK_REG1) & 0x08) >> 3);
288 	spin_unlock_irqrestore(&event_lock, flags);
289 
290 	return sprintf(buf, "0x%lX\n", ret_val);
291 }
292 
293 static DEVICE_ATTR(current_ref, S_IRUGO, show_current_ref, NULL);
294 
295 
296 static ssize_t show_telclock_version(struct device *d,
297 		struct device_attribute *attr, char *buf)
298 {
299 	unsigned long ret_val;
300 	unsigned long flags;
301 
302 	spin_lock_irqsave(&event_lock, flags);
303 	ret_val = inb(TLCLK_REG5);
304 	spin_unlock_irqrestore(&event_lock, flags);
305 
306 	return sprintf(buf, "0x%lX\n", ret_val);
307 }
308 
309 static DEVICE_ATTR(telclock_version, S_IRUGO,
310 		show_telclock_version, NULL);
311 
312 static ssize_t show_alarms(struct device *d,
313 		struct device_attribute *attr,  char *buf)
314 {
315 	unsigned long ret_val;
316 	unsigned long flags;
317 
318 	spin_lock_irqsave(&event_lock, flags);
319 	ret_val = (inb(TLCLK_REG2) & 0xf0);
320 	spin_unlock_irqrestore(&event_lock, flags);
321 
322 	return sprintf(buf, "0x%lX\n", ret_val);
323 }
324 
325 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
326 
327 static ssize_t store_received_ref_clk3a(struct device *d,
328 		 struct device_attribute *attr, const char *buf, size_t count)
329 {
330 	unsigned long tmp;
331 	unsigned char val;
332 	unsigned long flags;
333 
334 	sscanf(buf, "%lX", &tmp);
335 	dev_dbg(d, ": tmp = 0x%lX\n", tmp);
336 
337 	val = (unsigned char)tmp;
338 	spin_lock_irqsave(&event_lock, flags);
339 	SET_PORT_BITS(TLCLK_REG1, 0xef, val);
340 	spin_unlock_irqrestore(&event_lock, flags);
341 
342 	return strnlen(buf, count);
343 }
344 
345 static DEVICE_ATTR(received_ref_clk3a, (S_IWUSR|S_IWGRP), NULL,
346 		store_received_ref_clk3a);
347 
348 
349 static ssize_t store_received_ref_clk3b(struct device *d,
350 		 struct device_attribute *attr, const char *buf, size_t count)
351 {
352 	unsigned long tmp;
353 	unsigned char val;
354 	unsigned long flags;
355 
356 	sscanf(buf, "%lX", &tmp);
357 	dev_dbg(d, ": tmp = 0x%lX\n", tmp);
358 
359 	val = (unsigned char)tmp;
360 	spin_lock_irqsave(&event_lock, flags);
361 	SET_PORT_BITS(TLCLK_REG1, 0xdf, val << 1);
362 	spin_unlock_irqrestore(&event_lock, flags);
363 
364 	return strnlen(buf, count);
365 }
366 
367 static DEVICE_ATTR(received_ref_clk3b, (S_IWUSR|S_IWGRP), NULL,
368 		store_received_ref_clk3b);
369 
370 
371 static ssize_t store_enable_clk3b_output(struct device *d,
372 		 struct device_attribute *attr, const char *buf, size_t count)
373 {
374 	unsigned long tmp;
375 	unsigned char val;
376 	unsigned long flags;
377 
378 	sscanf(buf, "%lX", &tmp);
379 	dev_dbg(d, ": tmp = 0x%lX\n", tmp);
380 
381 	val = (unsigned char)tmp;
382 	spin_lock_irqsave(&event_lock, flags);
383 	SET_PORT_BITS(TLCLK_REG3, 0x7f, val << 7);
384 	spin_unlock_irqrestore(&event_lock, flags);
385 
386 	return strnlen(buf, count);
387 }
388 
389 static DEVICE_ATTR(enable_clk3b_output, (S_IWUSR|S_IWGRP), NULL,
390 		store_enable_clk3b_output);
391 
392 static ssize_t store_enable_clk3a_output(struct device *d,
393 		 struct device_attribute *attr, const char *buf, size_t count)
394 {
395 	unsigned long flags;
396 	unsigned long tmp;
397 	unsigned char val;
398 
399 	sscanf(buf, "%lX", &tmp);
400 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
401 
402 	val = (unsigned char)tmp;
403 	spin_lock_irqsave(&event_lock, flags);
404 	SET_PORT_BITS(TLCLK_REG3, 0xbf, val << 6);
405 	spin_unlock_irqrestore(&event_lock, flags);
406 
407 	return strnlen(buf, count);
408 }
409 
410 static DEVICE_ATTR(enable_clk3a_output, (S_IWUSR|S_IWGRP), NULL,
411 		store_enable_clk3a_output);
412 
413 static ssize_t store_enable_clkb1_output(struct device *d,
414 		 struct device_attribute *attr, const char *buf, size_t count)
415 {
416 	unsigned long flags;
417 	unsigned long tmp;
418 	unsigned char val;
419 
420 	sscanf(buf, "%lX", &tmp);
421 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
422 
423 	val = (unsigned char)tmp;
424 	spin_lock_irqsave(&event_lock, flags);
425 	SET_PORT_BITS(TLCLK_REG2, 0xf7, val << 3);
426 	spin_unlock_irqrestore(&event_lock, flags);
427 
428 	return strnlen(buf, count);
429 }
430 
431 static DEVICE_ATTR(enable_clkb1_output, (S_IWUSR|S_IWGRP), NULL,
432 		store_enable_clkb1_output);
433 
434 
435 static ssize_t store_enable_clka1_output(struct device *d,
436 		 struct device_attribute *attr, const char *buf, size_t count)
437 {
438 	unsigned long flags;
439 	unsigned long tmp;
440 	unsigned char val;
441 
442 	sscanf(buf, "%lX", &tmp);
443 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
444 
445 	val = (unsigned char)tmp;
446 	spin_lock_irqsave(&event_lock, flags);
447 	SET_PORT_BITS(TLCLK_REG2, 0xfb, val << 2);
448 	spin_unlock_irqrestore(&event_lock, flags);
449 
450 	return strnlen(buf, count);
451 }
452 
453 static DEVICE_ATTR(enable_clka1_output, (S_IWUSR|S_IWGRP), NULL,
454 		store_enable_clka1_output);
455 
456 static ssize_t store_enable_clkb0_output(struct device *d,
457 		 struct device_attribute *attr, const char *buf, size_t count)
458 {
459 	unsigned long flags;
460 	unsigned long tmp;
461 	unsigned char val;
462 
463 	sscanf(buf, "%lX", &tmp);
464 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
465 
466 	val = (unsigned char)tmp;
467 	spin_lock_irqsave(&event_lock, flags);
468 	SET_PORT_BITS(TLCLK_REG2, 0xfd, val << 1);
469 	spin_unlock_irqrestore(&event_lock, flags);
470 
471 	return strnlen(buf, count);
472 }
473 
474 static DEVICE_ATTR(enable_clkb0_output, (S_IWUSR|S_IWGRP), NULL,
475 		store_enable_clkb0_output);
476 
477 static ssize_t store_enable_clka0_output(struct device *d,
478 		 struct device_attribute *attr, const char *buf, size_t count)
479 {
480 	unsigned long flags;
481 	unsigned long tmp;
482 	unsigned char val;
483 
484 	sscanf(buf, "%lX", &tmp);
485 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
486 
487 	val = (unsigned char)tmp;
488 	spin_lock_irqsave(&event_lock, flags);
489 	SET_PORT_BITS(TLCLK_REG2, 0xfe, val);
490 	spin_unlock_irqrestore(&event_lock, flags);
491 
492 	return strnlen(buf, count);
493 }
494 
495 static DEVICE_ATTR(enable_clka0_output, (S_IWUSR|S_IWGRP), NULL,
496 		store_enable_clka0_output);
497 
498 static ssize_t store_select_amcb2_transmit_clock(struct device *d,
499 		struct device_attribute *attr, const char *buf, size_t count)
500 {
501 	unsigned long flags;
502 	unsigned long tmp;
503 	unsigned char val;
504 
505 	sscanf(buf, "%lX", &tmp);
506 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
507 
508 	val = (unsigned char)tmp;
509 	spin_lock_irqsave(&event_lock, flags);
510 	if ((val == CLK_8kHz) || (val == CLK_16_384MHz)) {
511 		SET_PORT_BITS(TLCLK_REG3, 0xc7, 0x28);
512 		SET_PORT_BITS(TLCLK_REG1, 0xfb, ~val);
513 	} else if (val >= CLK_8_592MHz) {
514 		SET_PORT_BITS(TLCLK_REG3, 0xc7, 0x38);
515 		switch (val) {
516 		case CLK_8_592MHz:
517 			SET_PORT_BITS(TLCLK_REG0, 0xfc, 2);
518 			break;
519 		case CLK_11_184MHz:
520 			SET_PORT_BITS(TLCLK_REG0, 0xfc, 0);
521 			break;
522 		case CLK_34_368MHz:
523 			SET_PORT_BITS(TLCLK_REG0, 0xfc, 3);
524 			break;
525 		case CLK_44_736MHz:
526 			SET_PORT_BITS(TLCLK_REG0, 0xfc, 1);
527 			break;
528 		}
529 	} else {
530 		SET_PORT_BITS(TLCLK_REG3, 0xc7, val << 3);
531 	}
532 	spin_unlock_irqrestore(&event_lock, flags);
533 
534 	return strnlen(buf, count);
535 }
536 
537 static DEVICE_ATTR(select_amcb2_transmit_clock, (S_IWUSR|S_IWGRP), NULL,
538 	store_select_amcb2_transmit_clock);
539 
540 static ssize_t store_select_amcb1_transmit_clock(struct device *d,
541 		 struct device_attribute *attr, const char *buf, size_t count)
542 {
543 	unsigned long tmp;
544 	unsigned char val;
545 	unsigned long flags;
546 
547 	sscanf(buf, "%lX", &tmp);
548 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
549 
550 	val = (unsigned char)tmp;
551 	spin_lock_irqsave(&event_lock, flags);
552 	if ((val == CLK_8kHz) || (val == CLK_16_384MHz)) {
553 		SET_PORT_BITS(TLCLK_REG3, 0xf8, 0x5);
554 		SET_PORT_BITS(TLCLK_REG1, 0xfb, ~val);
555 	} else if (val >= CLK_8_592MHz) {
556 		SET_PORT_BITS(TLCLK_REG3, 0xf8, 0x7);
557 		switch (val) {
558 		case CLK_8_592MHz:
559 			SET_PORT_BITS(TLCLK_REG0, 0xfc, 2);
560 			break;
561 		case CLK_11_184MHz:
562 			SET_PORT_BITS(TLCLK_REG0, 0xfc, 0);
563 			break;
564 		case CLK_34_368MHz:
565 			SET_PORT_BITS(TLCLK_REG0, 0xfc, 3);
566 			break;
567 		case CLK_44_736MHz:
568 			SET_PORT_BITS(TLCLK_REG0, 0xfc, 1);
569 			break;
570 		}
571 	} else {
572 		SET_PORT_BITS(TLCLK_REG3, 0xf8, val);
573 	}
574 	spin_unlock_irqrestore(&event_lock, flags);
575 
576 	return strnlen(buf, count);
577 }
578 
579 static DEVICE_ATTR(select_amcb1_transmit_clock, (S_IWUSR|S_IWGRP), NULL,
580 		store_select_amcb1_transmit_clock);
581 
582 static ssize_t store_select_redundant_clock(struct device *d,
583 		 struct device_attribute *attr, const char *buf, size_t count)
584 {
585 	unsigned long tmp;
586 	unsigned char val;
587 	unsigned long flags;
588 
589 	sscanf(buf, "%lX", &tmp);
590 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
591 
592 	val = (unsigned char)tmp;
593 	spin_lock_irqsave(&event_lock, flags);
594 	SET_PORT_BITS(TLCLK_REG1, 0xfe, val);
595 	spin_unlock_irqrestore(&event_lock, flags);
596 
597 	return strnlen(buf, count);
598 }
599 
600 static DEVICE_ATTR(select_redundant_clock, (S_IWUSR|S_IWGRP), NULL,
601 		store_select_redundant_clock);
602 
603 static ssize_t store_select_ref_frequency(struct device *d,
604 		 struct device_attribute *attr, const char *buf, size_t count)
605 {
606 	unsigned long tmp;
607 	unsigned char val;
608 	unsigned long flags;
609 
610 	sscanf(buf, "%lX", &tmp);
611 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
612 
613 	val = (unsigned char)tmp;
614 	spin_lock_irqsave(&event_lock, flags);
615 	SET_PORT_BITS(TLCLK_REG1, 0xfd, val);
616 	spin_unlock_irqrestore(&event_lock, flags);
617 
618 	return strnlen(buf, count);
619 }
620 
621 static DEVICE_ATTR(select_ref_frequency, (S_IWUSR|S_IWGRP), NULL,
622 		store_select_ref_frequency);
623 
624 static ssize_t store_filter_select(struct device *d,
625 		 struct device_attribute *attr, const char *buf, size_t count)
626 {
627 	unsigned long tmp;
628 	unsigned char val;
629 	unsigned long flags;
630 
631 	sscanf(buf, "%lX", &tmp);
632 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
633 
634 	val = (unsigned char)tmp;
635 	spin_lock_irqsave(&event_lock, flags);
636 	SET_PORT_BITS(TLCLK_REG0, 0xfb, val);
637 	spin_unlock_irqrestore(&event_lock, flags);
638 
639 	return strnlen(buf, count);
640 }
641 
642 static DEVICE_ATTR(filter_select, (S_IWUSR|S_IWGRP), NULL, store_filter_select);
643 
644 static ssize_t store_hardware_switching_mode(struct device *d,
645 		 struct device_attribute *attr, const char *buf, size_t count)
646 {
647 	unsigned long tmp;
648 	unsigned char val;
649 	unsigned long flags;
650 
651 	sscanf(buf, "%lX", &tmp);
652 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
653 
654 	val = (unsigned char)tmp;
655 	spin_lock_irqsave(&event_lock, flags);
656 	SET_PORT_BITS(TLCLK_REG0, 0xbf, val);
657 	spin_unlock_irqrestore(&event_lock, flags);
658 
659 	return strnlen(buf, count);
660 }
661 
662 static DEVICE_ATTR(hardware_switching_mode, (S_IWUSR|S_IWGRP), NULL,
663 		store_hardware_switching_mode);
664 
665 static ssize_t store_hardware_switching(struct device *d,
666 		 struct device_attribute *attr, const char *buf, size_t count)
667 {
668 	unsigned long tmp;
669 	unsigned char val;
670 	unsigned long flags;
671 
672 	sscanf(buf, "%lX", &tmp);
673 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
674 
675 	val = (unsigned char)tmp;
676 	spin_lock_irqsave(&event_lock, flags);
677 	SET_PORT_BITS(TLCLK_REG0, 0x7f, val);
678 	spin_unlock_irqrestore(&event_lock, flags);
679 
680 	return strnlen(buf, count);
681 }
682 
683 static DEVICE_ATTR(hardware_switching, (S_IWUSR|S_IWGRP), NULL,
684 		store_hardware_switching);
685 
686 static ssize_t store_refalign (struct device *d,
687 		 struct device_attribute *attr, const char *buf, size_t count)
688 {
689 	unsigned long tmp;
690 	unsigned long flags;
691 
692 	sscanf(buf, "%lX", &tmp);
693 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
694 	spin_lock_irqsave(&event_lock, flags);
695 	SET_PORT_BITS(TLCLK_REG0, 0xf7, 0);
696 	SET_PORT_BITS(TLCLK_REG0, 0xf7, 0x08);
697 	SET_PORT_BITS(TLCLK_REG0, 0xf7, 0);
698 	spin_unlock_irqrestore(&event_lock, flags);
699 
700 	return strnlen(buf, count);
701 }
702 
703 static DEVICE_ATTR(refalign, (S_IWUSR|S_IWGRP), NULL, store_refalign);
704 
705 static ssize_t store_mode_select (struct device *d,
706 		 struct device_attribute *attr, const char *buf, size_t count)
707 {
708 	unsigned long tmp;
709 	unsigned char val;
710 	unsigned long flags;
711 
712 	sscanf(buf, "%lX", &tmp);
713 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
714 
715 	val = (unsigned char)tmp;
716 	spin_lock_irqsave(&event_lock, flags);
717 	SET_PORT_BITS(TLCLK_REG0, 0xcf, val);
718 	spin_unlock_irqrestore(&event_lock, flags);
719 
720 	return strnlen(buf, count);
721 }
722 
723 static DEVICE_ATTR(mode_select, (S_IWUSR|S_IWGRP), NULL, store_mode_select);
724 
725 static ssize_t store_reset (struct device *d,
726 		 struct device_attribute *attr, const char *buf, size_t count)
727 {
728 	unsigned long tmp;
729 	unsigned char val;
730 	unsigned long flags;
731 
732 	sscanf(buf, "%lX", &tmp);
733 	dev_dbg(d, "tmp = 0x%lX\n", tmp);
734 
735 	val = (unsigned char)tmp;
736 	spin_lock_irqsave(&event_lock, flags);
737 	SET_PORT_BITS(TLCLK_REG4, 0xfd, val);
738 	spin_unlock_irqrestore(&event_lock, flags);
739 
740 	return strnlen(buf, count);
741 }
742 
743 static DEVICE_ATTR(reset, (S_IWUSR|S_IWGRP), NULL, store_reset);
744 
745 static struct attribute *tlclk_sysfs_entries[] = {
746 	&dev_attr_current_ref.attr,
747 	&dev_attr_telclock_version.attr,
748 	&dev_attr_alarms.attr,
749 	&dev_attr_received_ref_clk3a.attr,
750 	&dev_attr_received_ref_clk3b.attr,
751 	&dev_attr_enable_clk3a_output.attr,
752 	&dev_attr_enable_clk3b_output.attr,
753 	&dev_attr_enable_clkb1_output.attr,
754 	&dev_attr_enable_clka1_output.attr,
755 	&dev_attr_enable_clkb0_output.attr,
756 	&dev_attr_enable_clka0_output.attr,
757 	&dev_attr_select_amcb1_transmit_clock.attr,
758 	&dev_attr_select_amcb2_transmit_clock.attr,
759 	&dev_attr_select_redundant_clock.attr,
760 	&dev_attr_select_ref_frequency.attr,
761 	&dev_attr_filter_select.attr,
762 	&dev_attr_hardware_switching_mode.attr,
763 	&dev_attr_hardware_switching.attr,
764 	&dev_attr_refalign.attr,
765 	&dev_attr_mode_select.attr,
766 	&dev_attr_reset.attr,
767 	NULL
768 };
769 
770 static const struct attribute_group tlclk_attribute_group = {
771 	.name = NULL,		/* put in device directory */
772 	.attrs = tlclk_sysfs_entries,
773 };
774 
775 static struct platform_device *tlclk_device;
776 
777 static int __init tlclk_init(void)
778 {
779 	int ret;
780 
781 	telclk_interrupt = (inb(TLCLK_REG7) & 0x0f);
782 
783 	alarm_events = kzalloc( sizeof(struct tlclk_alarms), GFP_KERNEL);
784 	if (!alarm_events) {
785 		ret = -ENOMEM;
786 		goto out1;
787 	}
788 
789 	ret = register_chrdev(tlclk_major, "telco_clock", &tlclk_fops);
790 	if (ret < 0) {
791 		printk(KERN_ERR "tlclk: can't get major %d.\n", tlclk_major);
792 		kfree(alarm_events);
793 		return ret;
794 	}
795 	tlclk_major = ret;
796 
797 	/* Read telecom clock IRQ number (Set by BIOS) */
798 	if (!request_region(TLCLK_BASE, 8, "telco_clock")) {
799 		printk(KERN_ERR "tlclk: request_region 0x%X failed.\n",
800 			TLCLK_BASE);
801 		ret = -EBUSY;
802 		goto out2;
803 	}
804 
805 	if (0x0F == telclk_interrupt ) { /* not MCPBL0010 ? */
806 		printk(KERN_ERR "telclk_interrupt = 0x%x non-mcpbl0010 hw.\n",
807 			telclk_interrupt);
808 		ret = -ENXIO;
809 		goto out3;
810 	}
811 
812 	timer_setup(&switchover_timer, switchover_timeout, 0);
813 
814 	ret = misc_register(&tlclk_miscdev);
815 	if (ret < 0) {
816 		printk(KERN_ERR "tlclk: misc_register returns %d.\n", ret);
817 		goto out3;
818 	}
819 
820 	tlclk_device = platform_device_register_simple("telco_clock",
821 				-1, NULL, 0);
822 	if (IS_ERR(tlclk_device)) {
823 		printk(KERN_ERR "tlclk: platform_device_register failed.\n");
824 		ret = PTR_ERR(tlclk_device);
825 		goto out4;
826 	}
827 
828 	ret = sysfs_create_group(&tlclk_device->dev.kobj,
829 			&tlclk_attribute_group);
830 	if (ret) {
831 		printk(KERN_ERR "tlclk: failed to create sysfs device attributes.\n");
832 		goto out5;
833 	}
834 
835 	return 0;
836 out5:
837 	platform_device_unregister(tlclk_device);
838 out4:
839 	misc_deregister(&tlclk_miscdev);
840 out3:
841 	release_region(TLCLK_BASE, 8);
842 out2:
843 	kfree(alarm_events);
844 	unregister_chrdev(tlclk_major, "telco_clock");
845 out1:
846 	return ret;
847 }
848 
849 static void __exit tlclk_cleanup(void)
850 {
851 	sysfs_remove_group(&tlclk_device->dev.kobj, &tlclk_attribute_group);
852 	platform_device_unregister(tlclk_device);
853 	misc_deregister(&tlclk_miscdev);
854 	unregister_chrdev(tlclk_major, "telco_clock");
855 
856 	release_region(TLCLK_BASE, 8);
857 	del_timer_sync(&switchover_timer);
858 	kfree(alarm_events);
859 
860 }
861 
862 static void switchover_timeout(struct timer_list *unused)
863 {
864 	unsigned long flags = tlclk_timer_data;
865 
866 	if ((flags & 1)) {
867 		if ((inb(TLCLK_REG1) & 0x08) != (flags & 0x08))
868 			alarm_events->switchover_primary++;
869 	} else {
870 		if ((inb(TLCLK_REG1) & 0x08) != (flags & 0x08))
871 			alarm_events->switchover_secondary++;
872 	}
873 
874 	/* Alarm processing is done, wake up read task */
875 	del_timer(&switchover_timer);
876 	got_event = 1;
877 	wake_up(&wq);
878 }
879 
880 static irqreturn_t tlclk_interrupt(int irq, void *dev_id)
881 {
882 	unsigned long flags;
883 
884 	spin_lock_irqsave(&event_lock, flags);
885 	/* Read and clear interrupt events */
886 	int_events = inb(TLCLK_REG6);
887 
888 	/* Primary_Los changed from 0 to 1 ? */
889 	if (int_events & PRI_LOS_01_MASK) {
890 		if (inb(TLCLK_REG2) & SEC_LOST_MASK)
891 			alarm_events->lost_clocks++;
892 		else
893 			alarm_events->lost_primary_clock++;
894 	}
895 
896 	/* Primary_Los changed from 1 to 0 ? */
897 	if (int_events & PRI_LOS_10_MASK) {
898 		alarm_events->primary_clock_back++;
899 		SET_PORT_BITS(TLCLK_REG1, 0xFE, 1);
900 	}
901 	/* Secondary_Los changed from 0 to 1 ? */
902 	if (int_events & SEC_LOS_01_MASK) {
903 		if (inb(TLCLK_REG2) & PRI_LOST_MASK)
904 			alarm_events->lost_clocks++;
905 		else
906 			alarm_events->lost_secondary_clock++;
907 	}
908 	/* Secondary_Los changed from 1 to 0 ? */
909 	if (int_events & SEC_LOS_10_MASK) {
910 		alarm_events->secondary_clock_back++;
911 		SET_PORT_BITS(TLCLK_REG1, 0xFE, 0);
912 	}
913 	if (int_events & HOLDOVER_10_MASK)
914 		alarm_events->pll_end_holdover++;
915 
916 	if (int_events & UNLOCK_01_MASK)
917 		alarm_events->pll_lost_sync++;
918 
919 	if (int_events & UNLOCK_10_MASK)
920 		alarm_events->pll_sync++;
921 
922 	/* Holdover changed from 0 to 1 ? */
923 	if (int_events & HOLDOVER_01_MASK) {
924 		alarm_events->pll_holdover++;
925 
926 		/* TIMEOUT in ~10ms */
927 		switchover_timer.expires = jiffies + msecs_to_jiffies(10);
928 		tlclk_timer_data = inb(TLCLK_REG1);
929 		mod_timer(&switchover_timer, switchover_timer.expires);
930 	} else {
931 		got_event = 1;
932 		wake_up(&wq);
933 	}
934 	spin_unlock_irqrestore(&event_lock, flags);
935 
936 	return IRQ_HANDLED;
937 }
938 
939 module_init(tlclk_init);
940 module_exit(tlclk_cleanup);
941