1 /*
2  * Copyright 2003 Digi International (www.digi.com)
3  *	Scott H Kilau <Scott_Kilau at digi dot com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2, or (at your option)
8  * any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
12  * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
13  * PURPOSE.  See the GNU General Public License for more details.
14  */
15 
16 
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/pci.h>
20 #include <linux/slab.h>
21 #include <linux/sched.h>
22 #include "dgnc_driver.h"
23 #include "dgnc_pci.h"
24 #include "dgnc_mgmt.h"
25 #include "dgnc_tty.h"
26 #include "dgnc_cls.h"
27 #include "dgnc_neo.h"
28 #include "dgnc_sysfs.h"
29 
30 MODULE_LICENSE("GPL");
31 MODULE_AUTHOR("Digi International, http://www.digi.com");
32 MODULE_DESCRIPTION("Driver for the Digi International Neo and Classic PCI based product line");
33 MODULE_SUPPORTED_DEVICE("dgnc");
34 
35 /**************************************************************************
36  *
37  * protos for this file
38  *
39  */
40 static int		dgnc_start(void);
41 static int		dgnc_finalize_board_init(struct dgnc_board *brd);
42 static void		dgnc_init_globals(void);
43 static int		dgnc_found_board(struct pci_dev *pdev, int id);
44 static void		dgnc_cleanup_board(struct dgnc_board *brd);
45 static void		dgnc_poll_handler(ulong dummy);
46 static int		dgnc_init_one(struct pci_dev *pdev,
47 				      const struct pci_device_id *ent);
48 static void		dgnc_do_remap(struct dgnc_board *brd);
49 
50 /*
51  * File operations permitted on Control/Management major.
52  */
53 static const struct file_operations dgnc_BoardFops = {
54 	.owner		=	THIS_MODULE,
55 	.unlocked_ioctl =	dgnc_mgmt_ioctl,
56 	.open		=	dgnc_mgmt_open,
57 	.release	=	dgnc_mgmt_close
58 };
59 
60 
61 /*
62  * Globals
63  */
64 uint			dgnc_NumBoards;
65 struct dgnc_board		*dgnc_Board[MAXBOARDS];
66 DEFINE_SPINLOCK(dgnc_global_lock);
67 uint			dgnc_Major;
68 int			dgnc_poll_tick = 20;	/* Poll interval - 20 ms */
69 
70 /*
71  * Static vars.
72  */
73 static struct class *dgnc_class;
74 
75 /*
76  * Poller stuff
77  */
78 static DEFINE_SPINLOCK(dgnc_poll_lock); /* Poll scheduling lock */
79 static ulong		dgnc_poll_time; /* Time of next poll */
80 static uint		dgnc_poll_stop; /* Used to tell poller to stop */
81 static struct timer_list dgnc_poll_timer;
82 
83 
84 static const struct pci_device_id dgnc_pci_tbl[] = {
85 	{PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_4_DID),     .driver_data = 0},
86 	{PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_4_422_DID), .driver_data = 1},
87 	{PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_8_DID),     .driver_data = 2},
88 	{PCI_DEVICE(DIGI_VID, PCI_DEVICE_CLASSIC_8_422_DID), .driver_data = 3},
89 	{0,}
90 };
91 MODULE_DEVICE_TABLE(pci, dgnc_pci_tbl);
92 
93 struct board_id {
94 	unsigned char *name;
95 	uint maxports;
96 	unsigned int is_pci_express;
97 };
98 
99 static struct board_id dgnc_Ids[] = {
100 	{	PCI_DEVICE_CLASSIC_4_PCI_NAME,		4,	0	},
101 	{	PCI_DEVICE_CLASSIC_4_422_PCI_NAME,	4,	0	},
102 	{	PCI_DEVICE_CLASSIC_8_PCI_NAME,		8,	0	},
103 	{	PCI_DEVICE_CLASSIC_8_422_PCI_NAME,	8,	0	},
104 	{	PCI_DEVICE_NEO_4_PCI_NAME,		4,	0	},
105 	{	PCI_DEVICE_NEO_8_PCI_NAME,		8,	0	},
106 	{	PCI_DEVICE_NEO_2DB9_PCI_NAME,		2,	0	},
107 	{	PCI_DEVICE_NEO_2DB9PRI_PCI_NAME,	2,	0	},
108 	{	PCI_DEVICE_NEO_2RJ45_PCI_NAME,		2,	0	},
109 	{	PCI_DEVICE_NEO_2RJ45PRI_PCI_NAME,	2,	0	},
110 	{	PCI_DEVICE_NEO_1_422_PCI_NAME,		1,	0	},
111 	{	PCI_DEVICE_NEO_1_422_485_PCI_NAME,	1,	0	},
112 	{	PCI_DEVICE_NEO_2_422_485_PCI_NAME,	2,	0	},
113 	{	PCI_DEVICE_NEO_EXPRESS_8_PCI_NAME,	8,	1	},
114 	{	PCI_DEVICE_NEO_EXPRESS_4_PCI_NAME,	4,	1	},
115 	{	PCI_DEVICE_NEO_EXPRESS_4RJ45_PCI_NAME,	4,	1	},
116 	{	PCI_DEVICE_NEO_EXPRESS_8RJ45_PCI_NAME,	8,	1	},
117 	{	NULL,					0,	0	}
118 };
119 
120 static struct pci_driver dgnc_driver = {
121 	.name		= "dgnc",
122 	.probe		= dgnc_init_one,
123 	.id_table       = dgnc_pci_tbl,
124 };
125 
126 /************************************************************************
127  *
128  * Driver load/unload functions
129  *
130  ************************************************************************/
131 
132 /*
133  * dgnc_cleanup_module()
134  *
135  * Module unload.  This is where it all ends.
136  */
dgnc_cleanup_module(void)137 static void dgnc_cleanup_module(void)
138 {
139 	int i;
140 	unsigned long flags;
141 
142 	spin_lock_irqsave(&dgnc_poll_lock, flags);
143 	dgnc_poll_stop = 1;
144 	spin_unlock_irqrestore(&dgnc_poll_lock, flags);
145 
146 	/* Turn off poller right away. */
147 	del_timer_sync(&dgnc_poll_timer);
148 
149 	dgnc_remove_driver_sysfiles(&dgnc_driver);
150 
151 	device_destroy(dgnc_class, MKDEV(dgnc_Major, 0));
152 	class_destroy(dgnc_class);
153 	unregister_chrdev(dgnc_Major, "dgnc");
154 
155 	for (i = 0; i < dgnc_NumBoards; ++i) {
156 		dgnc_remove_ports_sysfiles(dgnc_Board[i]);
157 		dgnc_tty_uninit(dgnc_Board[i]);
158 		dgnc_cleanup_board(dgnc_Board[i]);
159 	}
160 
161 	dgnc_tty_post_uninit();
162 
163 	if (dgnc_NumBoards)
164 		pci_unregister_driver(&dgnc_driver);
165 }
166 
167 /*
168  * init_module()
169  *
170  * Module load.  This is where it all starts.
171  */
dgnc_init_module(void)172 static int __init dgnc_init_module(void)
173 {
174 	int rc = 0;
175 
176 	/*
177 	 * Initialize global stuff
178 	 */
179 	rc = dgnc_start();
180 
181 	if (rc < 0)
182 		return rc;
183 
184 	/*
185 	 * Find and configure all the cards
186 	 */
187 	rc = pci_register_driver(&dgnc_driver);
188 
189 	/*
190 	 * If something went wrong in the scan, bail out of driver.
191 	 */
192 	if (rc < 0) {
193 		/* Only unregister if it was actually registered. */
194 		if (dgnc_NumBoards)
195 			pci_unregister_driver(&dgnc_driver);
196 		else
197 			pr_warn("WARNING: dgnc driver load failed.  No Digi Neo or Classic boards found.\n");
198 
199 		dgnc_cleanup_module();
200 	} else {
201 		dgnc_create_driver_sysfiles(&dgnc_driver);
202 	}
203 
204 	return rc;
205 }
206 
207 module_init(dgnc_init_module);
208 module_exit(dgnc_cleanup_module);
209 
210 /*
211  * Start of driver.
212  */
dgnc_start(void)213 static int dgnc_start(void)
214 {
215 	int rc = 0;
216 	unsigned long flags;
217 	struct device *dev;
218 
219 	/* make sure that the globals are init'd before we do anything else */
220 	dgnc_init_globals();
221 
222 	/*
223 	 * Register our base character device into the kernel.
224 	 * This allows the download daemon to connect to the downld device
225 	 * before any of the boards are init'ed.
226 	 *
227 	 * Register management/dpa devices
228 	 */
229 	rc = register_chrdev(0, "dgnc", &dgnc_BoardFops);
230 	if (rc < 0) {
231 		pr_err(DRVSTR ": Can't register dgnc driver device (%d)\n", rc);
232 		return rc;
233 	}
234 	dgnc_Major = rc;
235 
236 	dgnc_class = class_create(THIS_MODULE, "dgnc_mgmt");
237 	if (IS_ERR(dgnc_class)) {
238 		rc = PTR_ERR(dgnc_class);
239 		pr_err(DRVSTR ": Can't create dgnc_mgmt class (%d)\n", rc);
240 		goto failed_class;
241 	}
242 
243 	dev = device_create(dgnc_class, NULL,
244 			MKDEV(dgnc_Major, 0),
245 			NULL, "dgnc_mgmt");
246 	if (IS_ERR(dev)) {
247 		rc = PTR_ERR(dev);
248 		pr_err(DRVSTR ": Can't create device (%d)\n", rc);
249 		goto failed_device;
250 	}
251 
252 	/*
253 	 * Init any global tty stuff.
254 	 */
255 	rc = dgnc_tty_preinit();
256 
257 	if (rc < 0) {
258 		pr_err(DRVSTR ": tty preinit - not enough memory (%d)\n", rc);
259 		goto failed_tty;
260 	}
261 
262 	/* Start the poller */
263 	spin_lock_irqsave(&dgnc_poll_lock, flags);
264 	setup_timer(&dgnc_poll_timer, dgnc_poll_handler, 0);
265 	dgnc_poll_time = jiffies + dgnc_jiffies_from_ms(dgnc_poll_tick);
266 	dgnc_poll_timer.expires = dgnc_poll_time;
267 	spin_unlock_irqrestore(&dgnc_poll_lock, flags);
268 
269 	add_timer(&dgnc_poll_timer);
270 
271 	return 0;
272 
273 failed_tty:
274 	device_destroy(dgnc_class, MKDEV(dgnc_Major, 0));
275 failed_device:
276 	class_destroy(dgnc_class);
277 failed_class:
278 	unregister_chrdev(dgnc_Major, "dgnc");
279 	return rc;
280 }
281 
282 /* returns count (>= 0), or negative on error */
dgnc_init_one(struct pci_dev * pdev,const struct pci_device_id * ent)283 static int dgnc_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
284 {
285 	int rc;
286 
287 	/* wake up and enable device */
288 	rc = pci_enable_device(pdev);
289 
290 	if (rc < 0) {
291 		rc = -EIO;
292 	} else {
293 		rc = dgnc_found_board(pdev, ent->driver_data);
294 		if (rc == 0)
295 			dgnc_NumBoards++;
296 	}
297 	return rc;
298 }
299 
300 /*
301  * dgnc_cleanup_board()
302  *
303  * Free all the memory associated with a board
304  */
dgnc_cleanup_board(struct dgnc_board * brd)305 static void dgnc_cleanup_board(struct dgnc_board *brd)
306 {
307 	int i = 0;
308 
309 	if (!brd || brd->magic != DGNC_BOARD_MAGIC)
310 		return;
311 
312 	switch (brd->device) {
313 	case PCI_DEVICE_CLASSIC_4_DID:
314 	case PCI_DEVICE_CLASSIC_8_DID:
315 	case PCI_DEVICE_CLASSIC_4_422_DID:
316 	case PCI_DEVICE_CLASSIC_8_422_DID:
317 
318 		/* Tell card not to interrupt anymore. */
319 		outb(0, brd->iobase + 0x4c);
320 		break;
321 
322 	default:
323 		break;
324 	}
325 
326 	if (brd->irq)
327 		free_irq(brd->irq, brd);
328 
329 	tasklet_kill(&brd->helper_tasklet);
330 
331 	if (brd->re_map_membase) {
332 		iounmap(brd->re_map_membase);
333 		brd->re_map_membase = NULL;
334 	}
335 
336 	if (brd->msgbuf_head) {
337 		unsigned long flags;
338 
339 		spin_lock_irqsave(&dgnc_global_lock, flags);
340 		brd->msgbuf = NULL;
341 		dev_dbg(&brd->pdev->dev, "%s\n", brd->msgbuf_head);
342 		kfree(brd->msgbuf_head);
343 		brd->msgbuf_head = NULL;
344 		spin_unlock_irqrestore(&dgnc_global_lock, flags);
345 	}
346 
347 	/* Free all allocated channels structs */
348 	for (i = 0; i < MAXPORTS ; i++) {
349 		if (brd->channels[i]) {
350 			kfree(brd->channels[i]->ch_rqueue);
351 			kfree(brd->channels[i]->ch_equeue);
352 			kfree(brd->channels[i]->ch_wqueue);
353 			kfree(brd->channels[i]);
354 			brd->channels[i] = NULL;
355 		}
356 	}
357 
358 	kfree(brd->flipbuf);
359 
360 	dgnc_Board[brd->boardnum] = NULL;
361 
362 	kfree(brd);
363 }
364 
365 
366 /*
367  * dgnc_found_board()
368  *
369  * A board has been found, init it.
370  */
dgnc_found_board(struct pci_dev * pdev,int id)371 static int dgnc_found_board(struct pci_dev *pdev, int id)
372 {
373 	struct dgnc_board *brd;
374 	unsigned int pci_irq;
375 	int i = 0;
376 	int rc = 0;
377 	unsigned long flags;
378 
379 	/* get the board structure and prep it */
380 	dgnc_Board[dgnc_NumBoards] = kzalloc(sizeof(*brd), GFP_KERNEL);
381 	brd = dgnc_Board[dgnc_NumBoards];
382 
383 	if (!brd)
384 		return -ENOMEM;
385 
386 	/* make a temporary message buffer for the boot messages */
387 	brd->msgbuf_head = kcalloc(8192, sizeof(u8), GFP_KERNEL);
388 	brd->msgbuf = brd->msgbuf_head;
389 
390 	if (!brd->msgbuf) {
391 		kfree(brd);
392 		return -ENOMEM;
393 	}
394 
395 	/* store the info for the board we've found */
396 	brd->magic = DGNC_BOARD_MAGIC;
397 	brd->boardnum = dgnc_NumBoards;
398 	brd->vendor = dgnc_pci_tbl[id].vendor;
399 	brd->device = dgnc_pci_tbl[id].device;
400 	brd->pdev = pdev;
401 	brd->pci_bus = pdev->bus->number;
402 	brd->pci_slot = PCI_SLOT(pdev->devfn);
403 	brd->name = dgnc_Ids[id].name;
404 	brd->maxports = dgnc_Ids[id].maxports;
405 	if (dgnc_Ids[i].is_pci_express)
406 		brd->bd_flags |= BD_IS_PCI_EXPRESS;
407 	brd->dpastatus = BD_NOFEP;
408 	init_waitqueue_head(&brd->state_wait);
409 
410 	spin_lock_init(&brd->bd_lock);
411 	spin_lock_init(&brd->bd_intr_lock);
412 
413 	brd->state		= BOARD_FOUND;
414 
415 	for (i = 0; i < MAXPORTS; i++)
416 		brd->channels[i] = NULL;
417 
418 	/* store which card & revision we have */
419 	pci_read_config_word(pdev, PCI_SUBSYSTEM_VENDOR_ID, &brd->subvendor);
420 	pci_read_config_word(pdev, PCI_SUBSYSTEM_ID, &brd->subdevice);
421 	pci_read_config_byte(pdev, PCI_REVISION_ID, &brd->rev);
422 
423 	pci_irq = pdev->irq;
424 	brd->irq = pci_irq;
425 
426 
427 	switch (brd->device) {
428 
429 	case PCI_DEVICE_CLASSIC_4_DID:
430 	case PCI_DEVICE_CLASSIC_8_DID:
431 	case PCI_DEVICE_CLASSIC_4_422_DID:
432 	case PCI_DEVICE_CLASSIC_8_422_DID:
433 
434 		brd->dpatype = T_CLASSIC | T_PCIBUS;
435 
436 		/*
437 		 * For PCI ClassicBoards
438 		 * PCI Local Address (i.e. "resource" number) space
439 		 * 0	PLX Memory Mapped Config
440 		 * 1	PLX I/O Mapped Config
441 		 * 2	I/O Mapped UARTs and Status
442 		 * 3	Memory Mapped VPD
443 		 * 4	Memory Mapped UARTs and Status
444 		 */
445 
446 
447 		/* get the PCI Base Address Registers */
448 		brd->membase = pci_resource_start(pdev, 4);
449 
450 		if (!brd->membase) {
451 			dev_err(&brd->pdev->dev,
452 				"Card has no PCI IO resources, failing.\n");
453 			return -ENODEV;
454 		}
455 
456 		brd->membase_end = pci_resource_end(pdev, 4);
457 
458 		if (brd->membase & 1)
459 			brd->membase &= ~3;
460 		else
461 			brd->membase &= ~15;
462 
463 		brd->iobase	= pci_resource_start(pdev, 1);
464 		brd->iobase_end = pci_resource_end(pdev, 1);
465 		brd->iobase	= ((unsigned int) (brd->iobase)) & 0xFFFE;
466 
467 		/* Assign the board_ops struct */
468 		brd->bd_ops = &dgnc_cls_ops;
469 
470 		brd->bd_uart_offset = 0x8;
471 		brd->bd_dividend = 921600;
472 
473 		dgnc_do_remap(brd);
474 
475 		/* Get and store the board VPD, if it exists */
476 		brd->bd_ops->vpd(brd);
477 
478 		/*
479 		 * Enable Local Interrupt 1		  (0x1),
480 		 * Local Interrupt 1 Polarity Active high (0x2),
481 		 * Enable PCI interrupt			  (0x40)
482 		 */
483 		outb(0x43, brd->iobase + 0x4c);
484 
485 		break;
486 
487 
488 	case PCI_DEVICE_NEO_4_DID:
489 	case PCI_DEVICE_NEO_8_DID:
490 	case PCI_DEVICE_NEO_2DB9_DID:
491 	case PCI_DEVICE_NEO_2DB9PRI_DID:
492 	case PCI_DEVICE_NEO_2RJ45_DID:
493 	case PCI_DEVICE_NEO_2RJ45PRI_DID:
494 	case PCI_DEVICE_NEO_1_422_DID:
495 	case PCI_DEVICE_NEO_1_422_485_DID:
496 	case PCI_DEVICE_NEO_2_422_485_DID:
497 	case PCI_DEVICE_NEO_EXPRESS_8_DID:
498 	case PCI_DEVICE_NEO_EXPRESS_4_DID:
499 	case PCI_DEVICE_NEO_EXPRESS_4RJ45_DID:
500 	case PCI_DEVICE_NEO_EXPRESS_8RJ45_DID:
501 
502 		/*
503 		 * This chip is set up 100% when we get to it.
504 		 * No need to enable global interrupts or anything.
505 		 */
506 		if (brd->bd_flags & BD_IS_PCI_EXPRESS)
507 			brd->dpatype = T_NEO_EXPRESS | T_PCIBUS;
508 		else
509 			brd->dpatype = T_NEO | T_PCIBUS;
510 
511 		/* get the PCI Base Address Registers */
512 		brd->membase     = pci_resource_start(pdev, 0);
513 		brd->membase_end = pci_resource_end(pdev, 0);
514 
515 		if (brd->membase & 1)
516 			brd->membase &= ~3;
517 		else
518 			brd->membase &= ~15;
519 
520 		/* Assign the board_ops struct */
521 		brd->bd_ops = &dgnc_neo_ops;
522 
523 		brd->bd_uart_offset = 0x200;
524 		brd->bd_dividend = 921600;
525 
526 		dgnc_do_remap(brd);
527 
528 		if (brd->re_map_membase) {
529 
530 			/* Read and store the dvid after remapping */
531 			brd->dvid = readb(brd->re_map_membase + 0x8D);
532 
533 			/* Get and store the board VPD, if it exists */
534 			brd->bd_ops->vpd(brd);
535 		}
536 		break;
537 
538 	default:
539 		dev_err(&brd->pdev->dev,
540 			"Didn't find any compatible Neo/Classic PCI boards.\n");
541 		return -ENXIO;
542 
543 	}
544 
545 	/*
546 	 * Do tty device initialization.
547 	 */
548 
549 	rc = dgnc_tty_register(brd);
550 	if (rc < 0) {
551 		pr_err(DRVSTR ": Can't register tty devices (%d)\n", rc);
552 		goto failed;
553 	}
554 
555 	rc = dgnc_finalize_board_init(brd);
556 	if (rc < 0) {
557 		pr_err(DRVSTR ": Can't finalize board init (%d)\n", rc);
558 		goto failed;
559 	}
560 
561 	rc = dgnc_tty_init(brd);
562 	if (rc < 0) {
563 		pr_err(DRVSTR ": Can't init tty devices (%d)\n", rc);
564 		goto failed;
565 	}
566 
567 	brd->state = BOARD_READY;
568 	brd->dpastatus = BD_RUNNING;
569 
570 	dgnc_create_ports_sysfiles(brd);
571 
572 	/* init our poll helper tasklet */
573 	tasklet_init(&brd->helper_tasklet,
574 		     brd->bd_ops->tasklet,
575 		     (unsigned long) brd);
576 
577 	spin_lock_irqsave(&dgnc_global_lock, flags);
578 	brd->msgbuf = NULL;
579 	dev_dbg(&brd->pdev->dev, "%s\n", brd->msgbuf_head);
580 	kfree(brd->msgbuf_head);
581 	brd->msgbuf_head = NULL;
582 	spin_unlock_irqrestore(&dgnc_global_lock, flags);
583 
584 	/*
585 	 * allocate flip buffer for board.
586 	 *
587 	 * Okay to malloc with GFP_KERNEL, we are not at interrupt
588 	 * context, and there are no locks held.
589 	 */
590 	brd->flipbuf = kzalloc(MYFLIPLEN, GFP_KERNEL);
591 
592 	wake_up_interruptible(&brd->state_wait);
593 
594 	return 0;
595 
596 failed:
597 	dgnc_tty_uninit(brd);
598 	brd->state = BOARD_FAILED;
599 	brd->dpastatus = BD_NOFEP;
600 
601 	return -ENXIO;
602 
603 }
604 
605 
dgnc_finalize_board_init(struct dgnc_board * brd)606 static int dgnc_finalize_board_init(struct dgnc_board *brd)
607 {
608 	int rc = 0;
609 
610 	if (!brd || brd->magic != DGNC_BOARD_MAGIC)
611 		return -ENODEV;
612 
613 	if (brd->irq) {
614 		rc = request_irq(brd->irq, brd->bd_ops->intr,
615 				 IRQF_SHARED, "DGNC", brd);
616 
617 		if (rc) {
618 			dev_err(&brd->pdev->dev,
619 				"Failed to hook IRQ %d\n", brd->irq);
620 			brd->state = BOARD_FAILED;
621 			brd->dpastatus = BD_NOFEP;
622 			rc = -ENODEV;
623 		}
624 	}
625 	return rc;
626 }
627 
628 /*
629  * Remap PCI memory.
630  */
dgnc_do_remap(struct dgnc_board * brd)631 static void dgnc_do_remap(struct dgnc_board *brd)
632 {
633 
634 	if (!brd || brd->magic != DGNC_BOARD_MAGIC)
635 		return;
636 
637 	brd->re_map_membase = ioremap(brd->membase, 0x1000);
638 }
639 
640 
641 /*****************************************************************************
642 *
643 * Function:
644 *
645 *    dgnc_poll_handler
646 *
647 * Author:
648 *
649 *    Scott H Kilau
650 *
651 * Parameters:
652 *
653 *    dummy -- ignored
654 *
655 * Return Values:
656 *
657 *    none
658 *
659 * Description:
660 *
661 *    As each timer expires, it determines (a) whether the "transmit"
662 *    waiter needs to be woken up, and (b) whether the poller needs to
663 *    be rescheduled.
664 *
665 ******************************************************************************/
666 
dgnc_poll_handler(ulong dummy)667 static void dgnc_poll_handler(ulong dummy)
668 {
669 	struct dgnc_board *brd;
670 	unsigned long flags;
671 	int i;
672 	unsigned long new_time;
673 
674 	/* Go thru each board, kicking off a tasklet for each if needed */
675 	for (i = 0; i < dgnc_NumBoards; i++) {
676 		brd = dgnc_Board[i];
677 
678 		spin_lock_irqsave(&brd->bd_lock, flags);
679 
680 		/* If board is in a failed state don't schedule a tasklet */
681 		if (brd->state == BOARD_FAILED) {
682 			spin_unlock_irqrestore(&brd->bd_lock, flags);
683 			continue;
684 		}
685 
686 		/* Schedule a poll helper task */
687 		tasklet_schedule(&brd->helper_tasklet);
688 
689 		spin_unlock_irqrestore(&brd->bd_lock, flags);
690 	}
691 
692 	/*
693 	 * Schedule ourself back at the nominal wakeup interval.
694 	 */
695 	spin_lock_irqsave(&dgnc_poll_lock, flags);
696 	dgnc_poll_time += dgnc_jiffies_from_ms(dgnc_poll_tick);
697 
698 	new_time = dgnc_poll_time - jiffies;
699 
700 	if ((ulong) new_time >= 2 * dgnc_poll_tick)
701 		dgnc_poll_time = jiffies + dgnc_jiffies_from_ms(dgnc_poll_tick);
702 
703 	setup_timer(&dgnc_poll_timer, dgnc_poll_handler, 0);
704 	dgnc_poll_timer.expires = dgnc_poll_time;
705 	spin_unlock_irqrestore(&dgnc_poll_lock, flags);
706 
707 	if (!dgnc_poll_stop)
708 		add_timer(&dgnc_poll_timer);
709 }
710 
711 /*
712  * dgnc_init_globals()
713  *
714  * This is where we initialize the globals from the static insmod
715  * configuration variables.  These are declared near the head of
716  * this file.
717  */
dgnc_init_globals(void)718 static void dgnc_init_globals(void)
719 {
720 	int i = 0;
721 
722 	dgnc_NumBoards		= 0;
723 
724 	for (i = 0; i < MAXBOARDS; i++)
725 		dgnc_Board[i] = NULL;
726 
727 	init_timer(&dgnc_poll_timer);
728 }
729 
730