xref: /openbmc/linux/drivers/vlynq/vlynq.c (revision fd589a8f)
1 /*
2  * Copyright (C) 2006, 2007 Eugene Konev <ejka@openwrt.org>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  *
18  * Parts of the VLYNQ specification can be found here:
19  * http://www.ti.com/litv/pdf/sprue36a
20  */
21 
22 #include <linux/init.h>
23 #include <linux/types.h>
24 #include <linux/kernel.h>
25 #include <linux/string.h>
26 #include <linux/device.h>
27 #include <linux/module.h>
28 #include <linux/errno.h>
29 #include <linux/platform_device.h>
30 #include <linux/interrupt.h>
31 #include <linux/device.h>
32 #include <linux/delay.h>
33 #include <linux/io.h>
34 
35 #include <linux/vlynq.h>
36 
37 #define VLYNQ_CTRL_PM_ENABLE		0x80000000
38 #define VLYNQ_CTRL_CLOCK_INT		0x00008000
39 #define VLYNQ_CTRL_CLOCK_DIV(x)		(((x) & 7) << 16)
40 #define VLYNQ_CTRL_INT_LOCAL		0x00004000
41 #define VLYNQ_CTRL_INT_ENABLE		0x00002000
42 #define VLYNQ_CTRL_INT_VECTOR(x)	(((x) & 0x1f) << 8)
43 #define VLYNQ_CTRL_INT2CFG		0x00000080
44 #define VLYNQ_CTRL_RESET		0x00000001
45 
46 #define VLYNQ_CTRL_CLOCK_MASK          (0x7 << 16)
47 
48 #define VLYNQ_INT_OFFSET		0x00000014
49 #define VLYNQ_REMOTE_OFFSET		0x00000080
50 
51 #define VLYNQ_STATUS_LINK		0x00000001
52 #define VLYNQ_STATUS_LERROR		0x00000080
53 #define VLYNQ_STATUS_RERROR		0x00000100
54 
55 #define VINT_ENABLE			0x00000100
56 #define VINT_TYPE_EDGE			0x00000080
57 #define VINT_LEVEL_LOW			0x00000040
58 #define VINT_VECTOR(x)			((x) & 0x1f)
59 #define VINT_OFFSET(irq)		(8 * ((irq) % 4))
60 
61 #define VLYNQ_AUTONEGO_V2		0x00010000
62 
63 struct vlynq_regs {
64 	u32 revision;
65 	u32 control;
66 	u32 status;
67 	u32 int_prio;
68 	u32 int_status;
69 	u32 int_pending;
70 	u32 int_ptr;
71 	u32 tx_offset;
72 	struct vlynq_mapping rx_mapping[4];
73 	u32 chip;
74 	u32 autonego;
75 	u32 unused[6];
76 	u32 int_device[8];
77 };
78 
79 #ifdef CONFIG_VLYNQ_DEBUG
80 static void vlynq_dump_regs(struct vlynq_device *dev)
81 {
82 	int i;
83 
84 	printk(KERN_DEBUG "VLYNQ local=%p remote=%p\n",
85 			dev->local, dev->remote);
86 	for (i = 0; i < 32; i++) {
87 		printk(KERN_DEBUG "VLYNQ: local %d: %08x\n",
88 			i + 1, ((u32 *)dev->local)[i]);
89 		printk(KERN_DEBUG "VLYNQ: remote %d: %08x\n",
90 			i + 1, ((u32 *)dev->remote)[i]);
91 	}
92 }
93 
94 static void vlynq_dump_mem(u32 *base, int count)
95 {
96 	int i;
97 
98 	for (i = 0; i < (count + 3) / 4; i++) {
99 		if (i % 4 == 0)
100 			printk(KERN_DEBUG "\nMEM[0x%04x]:", i * 4);
101 		printk(KERN_DEBUG " 0x%08x", *(base + i));
102 	}
103 	printk(KERN_DEBUG "\n");
104 }
105 #endif
106 
107 /* Check the VLYNQ link status with a given device */
108 static int vlynq_linked(struct vlynq_device *dev)
109 {
110 	int i;
111 
112 	for (i = 0; i < 100; i++)
113 		if (readl(&dev->local->status) & VLYNQ_STATUS_LINK)
114 			return 1;
115 		else
116 			cpu_relax();
117 
118 	return 0;
119 }
120 
121 static void vlynq_reset(struct vlynq_device *dev)
122 {
123 	writel(readl(&dev->local->control) | VLYNQ_CTRL_RESET,
124 			&dev->local->control);
125 
126 	/* Wait for the devices to finish resetting */
127 	msleep(5);
128 
129 	/* Remove reset bit */
130 	writel(readl(&dev->local->control) & ~VLYNQ_CTRL_RESET,
131 			&dev->local->control);
132 
133 	/* Give some time for the devices to settle */
134 	msleep(5);
135 }
136 
137 static void vlynq_irq_unmask(unsigned int irq)
138 {
139 	u32 val;
140 	struct vlynq_device *dev = get_irq_chip_data(irq);
141 	int virq;
142 
143 	BUG_ON(!dev);
144 	virq = irq - dev->irq_start;
145 	val = readl(&dev->remote->int_device[virq >> 2]);
146 	val |= (VINT_ENABLE | virq) << VINT_OFFSET(virq);
147 	writel(val, &dev->remote->int_device[virq >> 2]);
148 }
149 
150 static void vlynq_irq_mask(unsigned int irq)
151 {
152 	u32 val;
153 	struct vlynq_device *dev = get_irq_chip_data(irq);
154 	int virq;
155 
156 	BUG_ON(!dev);
157 	virq = irq - dev->irq_start;
158 	val = readl(&dev->remote->int_device[virq >> 2]);
159 	val &= ~(VINT_ENABLE << VINT_OFFSET(virq));
160 	writel(val, &dev->remote->int_device[virq >> 2]);
161 }
162 
163 static int vlynq_irq_type(unsigned int irq, unsigned int flow_type)
164 {
165 	u32 val;
166 	struct vlynq_device *dev = get_irq_chip_data(irq);
167 	int virq;
168 
169 	BUG_ON(!dev);
170 	virq = irq - dev->irq_start;
171 	val = readl(&dev->remote->int_device[virq >> 2]);
172 	switch (flow_type & IRQ_TYPE_SENSE_MASK) {
173 	case IRQ_TYPE_EDGE_RISING:
174 	case IRQ_TYPE_EDGE_FALLING:
175 	case IRQ_TYPE_EDGE_BOTH:
176 		val |= VINT_TYPE_EDGE << VINT_OFFSET(virq);
177 		val &= ~(VINT_LEVEL_LOW << VINT_OFFSET(virq));
178 		break;
179 	case IRQ_TYPE_LEVEL_HIGH:
180 		val &= ~(VINT_TYPE_EDGE << VINT_OFFSET(virq));
181 		val &= ~(VINT_LEVEL_LOW << VINT_OFFSET(virq));
182 		break;
183 	case IRQ_TYPE_LEVEL_LOW:
184 		val &= ~(VINT_TYPE_EDGE << VINT_OFFSET(virq));
185 		val |= VINT_LEVEL_LOW << VINT_OFFSET(virq);
186 		break;
187 	default:
188 		return -EINVAL;
189 	}
190 	writel(val, &dev->remote->int_device[virq >> 2]);
191 	return 0;
192 }
193 
194 static void vlynq_local_ack(unsigned int irq)
195 {
196 	struct vlynq_device *dev = get_irq_chip_data(irq);
197 
198 	u32 status = readl(&dev->local->status);
199 
200 	pr_debug("%s: local status: 0x%08x\n",
201 		       dev_name(&dev->dev), status);
202 	writel(status, &dev->local->status);
203 }
204 
205 static void vlynq_remote_ack(unsigned int irq)
206 {
207 	struct vlynq_device *dev = get_irq_chip_data(irq);
208 
209 	u32 status = readl(&dev->remote->status);
210 
211 	pr_debug("%s: remote status: 0x%08x\n",
212 		       dev_name(&dev->dev), status);
213 	writel(status, &dev->remote->status);
214 }
215 
216 static irqreturn_t vlynq_irq(int irq, void *dev_id)
217 {
218 	struct vlynq_device *dev = dev_id;
219 	u32 status;
220 	int virq = 0;
221 
222 	status = readl(&dev->local->int_status);
223 	writel(status, &dev->local->int_status);
224 
225 	if (unlikely(!status))
226 		spurious_interrupt();
227 
228 	while (status) {
229 		if (status & 1)
230 			do_IRQ(dev->irq_start + virq);
231 		status >>= 1;
232 		virq++;
233 	}
234 
235 	return IRQ_HANDLED;
236 }
237 
238 static struct irq_chip vlynq_irq_chip = {
239 	.name = "vlynq",
240 	.unmask = vlynq_irq_unmask,
241 	.mask = vlynq_irq_mask,
242 	.set_type = vlynq_irq_type,
243 };
244 
245 static struct irq_chip vlynq_local_chip = {
246 	.name = "vlynq local error",
247 	.unmask = vlynq_irq_unmask,
248 	.mask = vlynq_irq_mask,
249 	.ack = vlynq_local_ack,
250 };
251 
252 static struct irq_chip vlynq_remote_chip = {
253 	.name = "vlynq local error",
254 	.unmask = vlynq_irq_unmask,
255 	.mask = vlynq_irq_mask,
256 	.ack = vlynq_remote_ack,
257 };
258 
259 static int vlynq_setup_irq(struct vlynq_device *dev)
260 {
261 	u32 val;
262 	int i, virq;
263 
264 	if (dev->local_irq == dev->remote_irq) {
265 		printk(KERN_ERR
266 		       "%s: local vlynq irq should be different from remote\n",
267 		       dev_name(&dev->dev));
268 		return -EINVAL;
269 	}
270 
271 	/* Clear local and remote error bits */
272 	writel(readl(&dev->local->status), &dev->local->status);
273 	writel(readl(&dev->remote->status), &dev->remote->status);
274 
275 	/* Now setup interrupts */
276 	val = VLYNQ_CTRL_INT_VECTOR(dev->local_irq);
277 	val |= VLYNQ_CTRL_INT_ENABLE | VLYNQ_CTRL_INT_LOCAL |
278 		VLYNQ_CTRL_INT2CFG;
279 	val |= readl(&dev->local->control);
280 	writel(VLYNQ_INT_OFFSET, &dev->local->int_ptr);
281 	writel(val, &dev->local->control);
282 
283 	val = VLYNQ_CTRL_INT_VECTOR(dev->remote_irq);
284 	val |= VLYNQ_CTRL_INT_ENABLE;
285 	val |= readl(&dev->remote->control);
286 	writel(VLYNQ_INT_OFFSET, &dev->remote->int_ptr);
287 	writel(val, &dev->remote->int_ptr);
288 	writel(val, &dev->remote->control);
289 
290 	for (i = dev->irq_start; i <= dev->irq_end; i++) {
291 		virq = i - dev->irq_start;
292 		if (virq == dev->local_irq) {
293 			set_irq_chip_and_handler(i, &vlynq_local_chip,
294 						 handle_level_irq);
295 			set_irq_chip_data(i, dev);
296 		} else if (virq == dev->remote_irq) {
297 			set_irq_chip_and_handler(i, &vlynq_remote_chip,
298 						 handle_level_irq);
299 			set_irq_chip_data(i, dev);
300 		} else {
301 			set_irq_chip_and_handler(i, &vlynq_irq_chip,
302 						 handle_simple_irq);
303 			set_irq_chip_data(i, dev);
304 			writel(0, &dev->remote->int_device[virq >> 2]);
305 		}
306 	}
307 
308 	if (request_irq(dev->irq, vlynq_irq, IRQF_SHARED, "vlynq", dev)) {
309 		printk(KERN_ERR "%s: request_irq failed\n",
310 					dev_name(&dev->dev));
311 		return -EAGAIN;
312 	}
313 
314 	return 0;
315 }
316 
317 static void vlynq_device_release(struct device *dev)
318 {
319 	struct vlynq_device *vdev = to_vlynq_device(dev);
320 	kfree(vdev);
321 }
322 
323 static int vlynq_device_match(struct device *dev,
324 			      struct device_driver *drv)
325 {
326 	struct vlynq_device *vdev = to_vlynq_device(dev);
327 	struct vlynq_driver *vdrv = to_vlynq_driver(drv);
328 	struct vlynq_device_id *ids = vdrv->id_table;
329 
330 	while (ids->id) {
331 		if (ids->id == vdev->dev_id) {
332 			vdev->divisor = ids->divisor;
333 			vlynq_set_drvdata(vdev, ids);
334 			printk(KERN_INFO "Driver found for VLYNQ "
335 				"device: %08x\n", vdev->dev_id);
336 			return 1;
337 		}
338 		printk(KERN_DEBUG "Not using the %08x VLYNQ device's driver"
339 			" for VLYNQ device: %08x\n", ids->id, vdev->dev_id);
340 		ids++;
341 	}
342 	return 0;
343 }
344 
345 static int vlynq_device_probe(struct device *dev)
346 {
347 	struct vlynq_device *vdev = to_vlynq_device(dev);
348 	struct vlynq_driver *drv = to_vlynq_driver(dev->driver);
349 	struct vlynq_device_id *id = vlynq_get_drvdata(vdev);
350 	int result = -ENODEV;
351 
352 	if (drv->probe)
353 		result = drv->probe(vdev, id);
354 	if (result)
355 		put_device(dev);
356 	return result;
357 }
358 
359 static int vlynq_device_remove(struct device *dev)
360 {
361 	struct vlynq_driver *drv = to_vlynq_driver(dev->driver);
362 
363 	if (drv->remove)
364 		drv->remove(to_vlynq_device(dev));
365 
366 	return 0;
367 }
368 
369 int __vlynq_register_driver(struct vlynq_driver *driver, struct module *owner)
370 {
371 	driver->driver.name = driver->name;
372 	driver->driver.bus = &vlynq_bus_type;
373 	return driver_register(&driver->driver);
374 }
375 EXPORT_SYMBOL(__vlynq_register_driver);
376 
377 void vlynq_unregister_driver(struct vlynq_driver *driver)
378 {
379 	driver_unregister(&driver->driver);
380 }
381 EXPORT_SYMBOL(vlynq_unregister_driver);
382 
383 /*
384  * A VLYNQ remote device can clock the VLYNQ bus master
385  * using a dedicated clock line. In that case, both the
386  * remove device and the bus master should have the same
387  * serial clock dividers configured. Iterate through the
388  * 8 possible dividers until we actually link with the
389  * device.
390  */
391 static int __vlynq_try_remote(struct vlynq_device *dev)
392 {
393 	int i;
394 
395 	vlynq_reset(dev);
396 	for (i = dev->dev_id ? vlynq_rdiv2 : vlynq_rdiv8; dev->dev_id ?
397 			i <= vlynq_rdiv8 : i >= vlynq_rdiv2;
398 		dev->dev_id ? i++ : i--) {
399 
400 		if (!vlynq_linked(dev))
401 			break;
402 
403 		writel((readl(&dev->remote->control) &
404 				~VLYNQ_CTRL_CLOCK_MASK) |
405 				VLYNQ_CTRL_CLOCK_INT |
406 				VLYNQ_CTRL_CLOCK_DIV(i - vlynq_rdiv1),
407 				&dev->remote->control);
408 		writel((readl(&dev->local->control)
409 				& ~(VLYNQ_CTRL_CLOCK_INT |
410 				VLYNQ_CTRL_CLOCK_MASK)) |
411 				VLYNQ_CTRL_CLOCK_DIV(i - vlynq_rdiv1),
412 				&dev->local->control);
413 
414 		if (vlynq_linked(dev)) {
415 			printk(KERN_DEBUG
416 				"%s: using remote clock divisor %d\n",
417 				dev_name(&dev->dev), i - vlynq_rdiv1 + 1);
418 			dev->divisor = i;
419 			return 0;
420 		} else {
421 			vlynq_reset(dev);
422 		}
423 	}
424 
425 	return -ENODEV;
426 }
427 
428 /*
429  * A VLYNQ remote device can be clocked by the VLYNQ bus
430  * master using a dedicated clock line. In that case, only
431  * the bus master configures the serial clock divider.
432  * Iterate through the 8 possible dividers until we
433  * actually get a link with the device.
434  */
435 static int __vlynq_try_local(struct vlynq_device *dev)
436 {
437 	int i;
438 
439 	vlynq_reset(dev);
440 
441 	for (i = dev->dev_id ? vlynq_ldiv2 : vlynq_ldiv8; dev->dev_id ?
442 			i <= vlynq_ldiv8 : i >= vlynq_ldiv2;
443 		dev->dev_id ? i++ : i--) {
444 
445 		writel((readl(&dev->local->control) &
446 				~VLYNQ_CTRL_CLOCK_MASK) |
447 				VLYNQ_CTRL_CLOCK_INT |
448 				VLYNQ_CTRL_CLOCK_DIV(i - vlynq_ldiv1),
449 				&dev->local->control);
450 
451 		if (vlynq_linked(dev)) {
452 			printk(KERN_DEBUG
453 				"%s: using local clock divisor %d\n",
454 				dev_name(&dev->dev), i - vlynq_ldiv1 + 1);
455 			dev->divisor = i;
456 			return 0;
457 		} else {
458 			vlynq_reset(dev);
459 		}
460 	}
461 
462 	return -ENODEV;
463 }
464 
465 /*
466  * When using external clocking method, serial clock
467  * is supplied by an external oscillator, therefore we
468  * should mask the local clock bit in the clock control
469  * register for both the bus master and the remote device.
470  */
471 static int __vlynq_try_external(struct vlynq_device *dev)
472 {
473 	vlynq_reset(dev);
474 	if (!vlynq_linked(dev))
475 		return -ENODEV;
476 
477 	writel((readl(&dev->remote->control) &
478 			~VLYNQ_CTRL_CLOCK_INT),
479 			&dev->remote->control);
480 
481 	writel((readl(&dev->local->control) &
482 			~VLYNQ_CTRL_CLOCK_INT),
483 			&dev->local->control);
484 
485 	if (vlynq_linked(dev)) {
486 		printk(KERN_DEBUG "%s: using external clock\n",
487 			dev_name(&dev->dev));
488 			dev->divisor = vlynq_div_external;
489 		return 0;
490 	}
491 
492 	return -ENODEV;
493 }
494 
495 static int __vlynq_enable_device(struct vlynq_device *dev)
496 {
497 	int result;
498 	struct plat_vlynq_ops *ops = dev->dev.platform_data;
499 
500 	result = ops->on(dev);
501 	if (result)
502 		return result;
503 
504 	switch (dev->divisor) {
505 	case vlynq_div_external:
506 	case vlynq_div_auto:
507 		/* When the device is brought from reset it should have clock
508 		 * generation negotiated by hardware.
509 		 * Check which device is generating clocks and perform setup
510 		 * accordingly */
511 		if (vlynq_linked(dev) && readl(&dev->remote->control) &
512 		   VLYNQ_CTRL_CLOCK_INT) {
513 			if (!__vlynq_try_remote(dev) ||
514 				!__vlynq_try_local(dev)  ||
515 				!__vlynq_try_external(dev))
516 				return 0;
517 		} else {
518 			if (!__vlynq_try_external(dev) ||
519 				!__vlynq_try_local(dev)    ||
520 				!__vlynq_try_remote(dev))
521 				return 0;
522 		}
523 		break;
524 	case vlynq_ldiv1:
525 	case vlynq_ldiv2:
526 	case vlynq_ldiv3:
527 	case vlynq_ldiv4:
528 	case vlynq_ldiv5:
529 	case vlynq_ldiv6:
530 	case vlynq_ldiv7:
531 	case vlynq_ldiv8:
532 		writel(VLYNQ_CTRL_CLOCK_INT |
533 			VLYNQ_CTRL_CLOCK_DIV(dev->divisor -
534 			vlynq_ldiv1), &dev->local->control);
535 		writel(0, &dev->remote->control);
536 		if (vlynq_linked(dev)) {
537 			printk(KERN_DEBUG
538 				"%s: using local clock divisor %d\n",
539 				dev_name(&dev->dev),
540 				dev->divisor - vlynq_ldiv1 + 1);
541 			return 0;
542 		}
543 		break;
544 	case vlynq_rdiv1:
545 	case vlynq_rdiv2:
546 	case vlynq_rdiv3:
547 	case vlynq_rdiv4:
548 	case vlynq_rdiv5:
549 	case vlynq_rdiv6:
550 	case vlynq_rdiv7:
551 	case vlynq_rdiv8:
552 		writel(0, &dev->local->control);
553 		writel(VLYNQ_CTRL_CLOCK_INT |
554 			VLYNQ_CTRL_CLOCK_DIV(dev->divisor -
555 			vlynq_rdiv1), &dev->remote->control);
556 		if (vlynq_linked(dev)) {
557 			printk(KERN_DEBUG
558 				"%s: using remote clock divisor %d\n",
559 				dev_name(&dev->dev),
560 				dev->divisor - vlynq_rdiv1 + 1);
561 			return 0;
562 		}
563 		break;
564 	}
565 
566 	ops->off(dev);
567 	return -ENODEV;
568 }
569 
570 int vlynq_enable_device(struct vlynq_device *dev)
571 {
572 	struct plat_vlynq_ops *ops = dev->dev.platform_data;
573 	int result = -ENODEV;
574 
575 	result = __vlynq_enable_device(dev);
576 	if (result)
577 		return result;
578 
579 	result = vlynq_setup_irq(dev);
580 	if (result)
581 		ops->off(dev);
582 
583 	dev->enabled = !result;
584 	return result;
585 }
586 EXPORT_SYMBOL(vlynq_enable_device);
587 
588 
589 void vlynq_disable_device(struct vlynq_device *dev)
590 {
591 	struct plat_vlynq_ops *ops = dev->dev.platform_data;
592 
593 	dev->enabled = 0;
594 	free_irq(dev->irq, dev);
595 	ops->off(dev);
596 }
597 EXPORT_SYMBOL(vlynq_disable_device);
598 
599 int vlynq_set_local_mapping(struct vlynq_device *dev, u32 tx_offset,
600 			    struct vlynq_mapping *mapping)
601 {
602 	int i;
603 
604 	if (!dev->enabled)
605 		return -ENXIO;
606 
607 	writel(tx_offset, &dev->local->tx_offset);
608 	for (i = 0; i < 4; i++) {
609 		writel(mapping[i].offset, &dev->local->rx_mapping[i].offset);
610 		writel(mapping[i].size, &dev->local->rx_mapping[i].size);
611 	}
612 	return 0;
613 }
614 EXPORT_SYMBOL(vlynq_set_local_mapping);
615 
616 int vlynq_set_remote_mapping(struct vlynq_device *dev, u32 tx_offset,
617 			     struct vlynq_mapping *mapping)
618 {
619 	int i;
620 
621 	if (!dev->enabled)
622 		return -ENXIO;
623 
624 	writel(tx_offset, &dev->remote->tx_offset);
625 	for (i = 0; i < 4; i++) {
626 		writel(mapping[i].offset, &dev->remote->rx_mapping[i].offset);
627 		writel(mapping[i].size, &dev->remote->rx_mapping[i].size);
628 	}
629 	return 0;
630 }
631 EXPORT_SYMBOL(vlynq_set_remote_mapping);
632 
633 int vlynq_set_local_irq(struct vlynq_device *dev, int virq)
634 {
635 	int irq = dev->irq_start + virq;
636 	if (dev->enabled)
637 		return -EBUSY;
638 
639 	if ((irq < dev->irq_start) || (irq > dev->irq_end))
640 		return -EINVAL;
641 
642 	if (virq == dev->remote_irq)
643 		return -EINVAL;
644 
645 	dev->local_irq = virq;
646 
647 	return 0;
648 }
649 EXPORT_SYMBOL(vlynq_set_local_irq);
650 
651 int vlynq_set_remote_irq(struct vlynq_device *dev, int virq)
652 {
653 	int irq = dev->irq_start + virq;
654 	if (dev->enabled)
655 		return -EBUSY;
656 
657 	if ((irq < dev->irq_start) || (irq > dev->irq_end))
658 		return -EINVAL;
659 
660 	if (virq == dev->local_irq)
661 		return -EINVAL;
662 
663 	dev->remote_irq = virq;
664 
665 	return 0;
666 }
667 EXPORT_SYMBOL(vlynq_set_remote_irq);
668 
669 static int vlynq_probe(struct platform_device *pdev)
670 {
671 	struct vlynq_device *dev;
672 	struct resource *regs_res, *mem_res, *irq_res;
673 	int len, result;
674 
675 	regs_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
676 	if (!regs_res)
677 		return -ENODEV;
678 
679 	mem_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem");
680 	if (!mem_res)
681 		return -ENODEV;
682 
683 	irq_res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "devirq");
684 	if (!irq_res)
685 		return -ENODEV;
686 
687 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
688 	if (!dev) {
689 		printk(KERN_ERR
690 		       "vlynq: failed to allocate device structure\n");
691 		return -ENOMEM;
692 	}
693 
694 	dev->id = pdev->id;
695 	dev->dev.bus = &vlynq_bus_type;
696 	dev->dev.parent = &pdev->dev;
697 	dev_set_name(&dev->dev, "vlynq%d", dev->id);
698 	dev->dev.platform_data = pdev->dev.platform_data;
699 	dev->dev.release = vlynq_device_release;
700 
701 	dev->regs_start = regs_res->start;
702 	dev->regs_end = regs_res->end;
703 	dev->mem_start = mem_res->start;
704 	dev->mem_end = mem_res->end;
705 
706 	len = regs_res->end - regs_res->start;
707 	if (!request_mem_region(regs_res->start, len, dev_name(&dev->dev))) {
708 		printk(KERN_ERR "%s: Can't request vlynq registers\n",
709 		       dev_name(&dev->dev));
710 		result = -ENXIO;
711 		goto fail_request;
712 	}
713 
714 	dev->local = ioremap(regs_res->start, len);
715 	if (!dev->local) {
716 		printk(KERN_ERR "%s: Can't remap vlynq registers\n",
717 		       dev_name(&dev->dev));
718 		result = -ENXIO;
719 		goto fail_remap;
720 	}
721 
722 	dev->remote = (struct vlynq_regs *)((void *)dev->local +
723 					    VLYNQ_REMOTE_OFFSET);
724 
725 	dev->irq = platform_get_irq_byname(pdev, "irq");
726 	dev->irq_start = irq_res->start;
727 	dev->irq_end = irq_res->end;
728 	dev->local_irq = dev->irq_end - dev->irq_start;
729 	dev->remote_irq = dev->local_irq - 1;
730 
731 	if (device_register(&dev->dev))
732 		goto fail_register;
733 	platform_set_drvdata(pdev, dev);
734 
735 	printk(KERN_INFO "%s: regs 0x%p, irq %d, mem 0x%p\n",
736 	       dev_name(&dev->dev), (void *)dev->regs_start, dev->irq,
737 	       (void *)dev->mem_start);
738 
739 	dev->dev_id = 0;
740 	dev->divisor = vlynq_div_auto;
741 	result = __vlynq_enable_device(dev);
742 	if (result == 0) {
743 		dev->dev_id = readl(&dev->remote->chip);
744 		((struct plat_vlynq_ops *)(dev->dev.platform_data))->off(dev);
745 	}
746 	if (dev->dev_id)
747 		printk(KERN_INFO "Found a VLYNQ device: %08x\n", dev->dev_id);
748 
749 	return 0;
750 
751 fail_register:
752 	iounmap(dev->local);
753 fail_remap:
754 fail_request:
755 	release_mem_region(regs_res->start, len);
756 	kfree(dev);
757 	return result;
758 }
759 
760 static int vlynq_remove(struct platform_device *pdev)
761 {
762 	struct vlynq_device *dev = platform_get_drvdata(pdev);
763 
764 	device_unregister(&dev->dev);
765 	iounmap(dev->local);
766 	release_mem_region(dev->regs_start, dev->regs_end - dev->regs_start);
767 
768 	kfree(dev);
769 
770 	return 0;
771 }
772 
773 static struct platform_driver vlynq_platform_driver = {
774 	.driver.name = "vlynq",
775 	.probe = vlynq_probe,
776 	.remove = __devexit_p(vlynq_remove),
777 };
778 
779 struct bus_type vlynq_bus_type = {
780 	.name = "vlynq",
781 	.match = vlynq_device_match,
782 	.probe = vlynq_device_probe,
783 	.remove = vlynq_device_remove,
784 };
785 EXPORT_SYMBOL(vlynq_bus_type);
786 
787 static int __devinit vlynq_init(void)
788 {
789 	int res = 0;
790 
791 	res = bus_register(&vlynq_bus_type);
792 	if (res)
793 		goto fail_bus;
794 
795 	res = platform_driver_register(&vlynq_platform_driver);
796 	if (res)
797 		goto fail_platform;
798 
799 	return 0;
800 
801 fail_platform:
802 	bus_unregister(&vlynq_bus_type);
803 fail_bus:
804 	return res;
805 }
806 
807 static void __devexit vlynq_exit(void)
808 {
809 	platform_driver_unregister(&vlynq_platform_driver);
810 	bus_unregister(&vlynq_bus_type);
811 }
812 
813 module_init(vlynq_init);
814 module_exit(vlynq_exit);
815