1/*
2 * Core maple bus functionality
3 *
4 * Copyright (C) 2007 - 2009 Adrian McMenamin
5 * Copyright (C) 2001 - 2008 Paul Mundt
6 * Copyright (C) 2000 - 2001 YAEGASHI Takeshi
7 * Copyright (C) 2001 M. R. Brown
8 *
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file "COPYING" in the main directory of this archive
11 * for more details.
12 */
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/device.h>
16#include <linux/interrupt.h>
17#include <linux/list.h>
18#include <linux/io.h>
19#include <linux/slab.h>
20#include <linux/maple.h>
21#include <linux/dma-mapping.h>
22#include <linux/delay.h>
23#include <linux/module.h>
24#include <asm/cacheflush.h>
25#include <asm/dma.h>
26#include <asm/io.h>
27#include <mach/dma.h>
28#include <mach/sysasic.h>
29
30MODULE_AUTHOR("Adrian McMenamin <adrian@mcmen.demon.co.uk>");
31MODULE_DESCRIPTION("Maple bus driver for Dreamcast");
32MODULE_LICENSE("GPL v2");
33
34static void maple_dma_handler(struct work_struct *work);
35static void maple_vblank_handler(struct work_struct *work);
36
37static DECLARE_WORK(maple_dma_process, maple_dma_handler);
38static DECLARE_WORK(maple_vblank_process, maple_vblank_handler);
39
40static LIST_HEAD(maple_waitq);
41static LIST_HEAD(maple_sentq);
42
43/* mutex to protect queue of waiting packets */
44static DEFINE_MUTEX(maple_wlist_lock);
45
46static struct maple_driver maple_unsupported_device;
47static struct device maple_bus;
48static int subdevice_map[MAPLE_PORTS];
49static unsigned long *maple_sendbuf, *maple_sendptr, *maple_lastptr;
50static unsigned long maple_pnp_time;
51static int started, scanning, fullscan;
52static struct kmem_cache *maple_queue_cache;
53
54struct maple_device_specify {
55 int port;
56 int unit;
57};
58
59static bool checked[MAPLE_PORTS];
60static bool empty[MAPLE_PORTS];
61static struct maple_device *baseunits[MAPLE_PORTS];
62
63/**
64 * maple_driver_register - register a maple driver
65 * @drv: maple driver to be registered.
66 *
67 * Registers the passed in @drv, while updating the bus type.
68 * Devices with matching function IDs will be automatically probed.
69 */
70int maple_driver_register(struct maple_driver *drv)
71{
72 if (!drv)
73 return -EINVAL;
74
75 drv->drv.bus = &maple_bus_type;
76
77 return driver_register(drv: &drv->drv);
78}
79EXPORT_SYMBOL_GPL(maple_driver_register);
80
81/**
82 * maple_driver_unregister - unregister a maple driver.
83 * @drv: maple driver to unregister.
84 *
85 * Cleans up after maple_driver_register(). To be invoked in the exit
86 * path of any module drivers.
87 */
88void maple_driver_unregister(struct maple_driver *drv)
89{
90 driver_unregister(drv: &drv->drv);
91}
92EXPORT_SYMBOL_GPL(maple_driver_unregister);
93
94/* set hardware registers to enable next round of dma */
95static void maple_dma_reset(void)
96{
97 __raw_writel(val: MAPLE_MAGIC, addr: MAPLE_RESET);
98 /* set trig type to 0 for software trigger, 1 for hardware (VBLANK) */
99 __raw_writel(val: 1, addr: MAPLE_TRIGTYPE);
100 /*
101 * Maple system register
102 * bits 31 - 16 timeout in units of 20nsec
103 * bit 12 hard trigger - set 0 to keep responding to VBLANK
104 * bits 9 - 8 set 00 for 2 Mbps, 01 for 1 Mbps
105 * bits 3 - 0 delay (in 1.3ms) between VBLANK and start of DMA
106 * max delay is 11
107 */
108 __raw_writel(val: MAPLE_2MBPS | MAPLE_TIMEOUT(0xFFFF), addr: MAPLE_SPEED);
109 __raw_writel(virt_to_phys(address: maple_sendbuf), addr: MAPLE_DMAADDR);
110 __raw_writel(val: 1, addr: MAPLE_ENABLE);
111}
112
113/**
114 * maple_getcond_callback - setup handling MAPLE_COMMAND_GETCOND
115 * @dev: device responding
116 * @callback: handler callback
117 * @interval: interval in jiffies between callbacks
118 * @function: the function code for the device
119 */
120void maple_getcond_callback(struct maple_device *dev,
121 void (*callback) (struct mapleq *mq),
122 unsigned long interval, unsigned long function)
123{
124 dev->callback = callback;
125 dev->interval = interval;
126 dev->function = cpu_to_be32(function);
127 dev->when = jiffies;
128}
129EXPORT_SYMBOL_GPL(maple_getcond_callback);
130
131static int maple_dma_done(void)
132{
133 return (__raw_readl(MAPLE_STATE) & 1) == 0;
134}
135
136static void maple_release_device(struct device *dev)
137{
138 struct maple_device *mdev;
139 struct mapleq *mq;
140
141 mdev = to_maple_dev(dev);
142 mq = mdev->mq;
143 kmem_cache_free(s: maple_queue_cache, objp: mq->recvbuf);
144 kfree(objp: mq);
145 kfree(objp: mdev);
146}
147
148/**
149 * maple_add_packet - add a single instruction to the maple bus queue
150 * @mdev: maple device
151 * @function: function on device being queried
152 * @command: maple command to add
153 * @length: length of command string (in 32 bit words)
154 * @data: remainder of command string
155 */
156int maple_add_packet(struct maple_device *mdev, u32 function, u32 command,
157 size_t length, void *data)
158{
159 int ret = 0;
160 void *sendbuf = NULL;
161
162 if (length) {
163 sendbuf = kcalloc(n: length, size: 4, GFP_KERNEL);
164 if (!sendbuf) {
165 ret = -ENOMEM;
166 goto out;
167 }
168 ((__be32 *)sendbuf)[0] = cpu_to_be32(function);
169 }
170
171 mdev->mq->command = command;
172 mdev->mq->length = length;
173 if (length > 1)
174 memcpy(sendbuf + 4, data, (length - 1) * 4);
175 mdev->mq->sendbuf = sendbuf;
176
177 mutex_lock(&maple_wlist_lock);
178 list_add_tail(new: &mdev->mq->list, head: &maple_waitq);
179 mutex_unlock(lock: &maple_wlist_lock);
180out:
181 return ret;
182}
183EXPORT_SYMBOL_GPL(maple_add_packet);
184
185static struct mapleq *maple_allocq(struct maple_device *mdev)
186{
187 struct mapleq *mq;
188
189 mq = kzalloc(size: sizeof(*mq), GFP_KERNEL);
190 if (!mq)
191 goto failed_nomem;
192
193 INIT_LIST_HEAD(list: &mq->list);
194 mq->dev = mdev;
195 mq->recvbuf = kmem_cache_zalloc(k: maple_queue_cache, GFP_KERNEL);
196 if (!mq->recvbuf)
197 goto failed_p2;
198 mq->recvbuf->buf = &((mq->recvbuf->bufx)[0]);
199
200 return mq;
201
202failed_p2:
203 kfree(objp: mq);
204failed_nomem:
205 dev_err(&mdev->dev, "could not allocate memory for device (%d, %d)\n",
206 mdev->port, mdev->unit);
207 return NULL;
208}
209
210static struct maple_device *maple_alloc_dev(int port, int unit)
211{
212 struct maple_device *mdev;
213
214 /* zero this out to avoid kobj subsystem
215 * thinking it has already been registered */
216
217 mdev = kzalloc(size: sizeof(*mdev), GFP_KERNEL);
218 if (!mdev)
219 return NULL;
220
221 mdev->port = port;
222 mdev->unit = unit;
223
224 mdev->mq = maple_allocq(mdev);
225
226 if (!mdev->mq) {
227 kfree(objp: mdev);
228 return NULL;
229 }
230 mdev->dev.bus = &maple_bus_type;
231 mdev->dev.parent = &maple_bus;
232 init_waitqueue_head(&mdev->maple_wait);
233 return mdev;
234}
235
236static void maple_free_dev(struct maple_device *mdev)
237{
238 kmem_cache_free(s: maple_queue_cache, objp: mdev->mq->recvbuf);
239 kfree(objp: mdev->mq);
240 kfree(objp: mdev);
241}
242
243/* process the command queue into a maple command block
244 * terminating command has bit 32 of first long set to 0
245 */
246static void maple_build_block(struct mapleq *mq)
247{
248 int port, unit, from, to, len;
249 unsigned long *lsendbuf = mq->sendbuf;
250
251 port = mq->dev->port & 3;
252 unit = mq->dev->unit;
253 len = mq->length;
254 from = port << 6;
255 to = (port << 6) | (unit > 0 ? (1 << (unit - 1)) & 0x1f : 0x20);
256
257 *maple_lastptr &= 0x7fffffff;
258 maple_lastptr = maple_sendptr;
259
260 *maple_sendptr++ = (port << 16) | len | 0x80000000;
261 *maple_sendptr++ = virt_to_phys(address: mq->recvbuf->buf);
262 *maple_sendptr++ =
263 mq->command | (to << 8) | (from << 16) | (len << 24);
264 while (len-- > 0)
265 *maple_sendptr++ = *lsendbuf++;
266}
267
268/* build up command queue */
269static void maple_send(void)
270{
271 int i, maple_packets = 0;
272 struct mapleq *mq, *nmq;
273
274 if (!maple_dma_done())
275 return;
276
277 /* disable DMA */
278 __raw_writel(val: 0, addr: MAPLE_ENABLE);
279
280 if (!list_empty(head: &maple_sentq))
281 goto finish;
282
283 mutex_lock(&maple_wlist_lock);
284 if (list_empty(head: &maple_waitq)) {
285 mutex_unlock(lock: &maple_wlist_lock);
286 goto finish;
287 }
288
289 maple_lastptr = maple_sendbuf;
290 maple_sendptr = maple_sendbuf;
291
292 list_for_each_entry_safe(mq, nmq, &maple_waitq, list) {
293 maple_build_block(mq);
294 list_del_init(entry: &mq->list);
295 list_add_tail(new: &mq->list, head: &maple_sentq);
296 if (maple_packets++ > MAPLE_MAXPACKETS)
297 break;
298 }
299 mutex_unlock(lock: &maple_wlist_lock);
300 if (maple_packets > 0) {
301 for (i = 0; i < (1 << MAPLE_DMA_PAGES); i++)
302 __flush_purge_region(maple_sendbuf + i * PAGE_SIZE,
303 PAGE_SIZE);
304 }
305
306finish:
307 maple_dma_reset();
308}
309
310/* check if there is a driver registered likely to match this device */
311static int maple_check_matching_driver(struct device_driver *driver,
312 void *devptr)
313{
314 struct maple_driver *maple_drv;
315 struct maple_device *mdev;
316
317 mdev = devptr;
318 maple_drv = to_maple_driver(driver);
319 if (mdev->devinfo.function & cpu_to_be32(maple_drv->function))
320 return 1;
321 return 0;
322}
323
324static void maple_detach_driver(struct maple_device *mdev)
325{
326 device_unregister(dev: &mdev->dev);
327}
328
329/* process initial MAPLE_COMMAND_DEVINFO for each device or port */
330static void maple_attach_driver(struct maple_device *mdev)
331{
332 char *p, *recvbuf;
333 unsigned long function;
334 int matched, error;
335
336 recvbuf = mdev->mq->recvbuf->buf;
337 /* copy the data as individual elements in
338 * case of memory optimisation */
339 memcpy(&mdev->devinfo.function, recvbuf + 4, 4);
340 memcpy(&mdev->devinfo.function_data[0], recvbuf + 8, 12);
341 memcpy(&mdev->devinfo.area_code, recvbuf + 20, 1);
342 memcpy(&mdev->devinfo.connector_direction, recvbuf + 21, 1);
343 memcpy(&mdev->devinfo.product_name[0], recvbuf + 22, 30);
344 memcpy(&mdev->devinfo.standby_power, recvbuf + 112, 2);
345 memcpy(&mdev->devinfo.max_power, recvbuf + 114, 2);
346 memcpy(mdev->product_name, mdev->devinfo.product_name, 30);
347 mdev->product_name[30] = '\0';
348 memcpy(mdev->product_licence, mdev->devinfo.product_licence, 60);
349 mdev->product_licence[60] = '\0';
350
351 for (p = mdev->product_name + 29; mdev->product_name <= p; p--)
352 if (*p == ' ')
353 *p = '\0';
354 else
355 break;
356 for (p = mdev->product_licence + 59; mdev->product_licence <= p; p--)
357 if (*p == ' ')
358 *p = '\0';
359 else
360 break;
361
362 function = be32_to_cpu(mdev->devinfo.function);
363
364 dev_info(&mdev->dev, "detected %s: function 0x%lX: at (%d, %d)\n",
365 mdev->product_name, function, mdev->port, mdev->unit);
366
367 if (function > 0x200) {
368 /* Do this silently - as not a real device */
369 function = 0;
370 mdev->driver = &maple_unsupported_device;
371 dev_set_name(dev: &mdev->dev, name: "%d:0.port", mdev->port);
372 } else {
373 matched =
374 bus_for_each_drv(bus: &maple_bus_type, NULL, data: mdev,
375 fn: maple_check_matching_driver);
376
377 if (matched == 0) {
378 /* Driver does not exist yet */
379 dev_info(&mdev->dev, "no driver found\n");
380 mdev->driver = &maple_unsupported_device;
381 }
382 dev_set_name(dev: &mdev->dev, name: "%d:0%d.%lX", mdev->port,
383 mdev->unit, function);
384 }
385
386 mdev->function = function;
387 mdev->dev.release = &maple_release_device;
388
389 atomic_set(v: &mdev->busy, i: 0);
390 error = device_register(dev: &mdev->dev);
391 if (error) {
392 dev_warn(&mdev->dev, "could not register device at"
393 " (%d, %d), with error 0x%X\n", mdev->unit,
394 mdev->port, error);
395 maple_free_dev(mdev);
396 mdev = NULL;
397 return;
398 }
399}
400
401/*
402 * if device has been registered for the given
403 * port and unit then return 1 - allows identification
404 * of which devices need to be attached or detached
405 */
406static int check_maple_device(struct device *device, void *portptr)
407{
408 struct maple_device_specify *ds;
409 struct maple_device *mdev;
410
411 ds = portptr;
412 mdev = to_maple_dev(device);
413 if (mdev->port == ds->port && mdev->unit == ds->unit)
414 return 1;
415 return 0;
416}
417
418static int setup_maple_commands(struct device *device, void *ignored)
419{
420 int add;
421 struct maple_device *mdev = to_maple_dev(device);
422 if (mdev->interval > 0 && atomic_read(v: &mdev->busy) == 0 &&
423 time_after(jiffies, mdev->when)) {
424 /* bounce if we cannot add */
425 add = maple_add_packet(mdev,
426 be32_to_cpu(mdev->devinfo.function),
427 MAPLE_COMMAND_GETCOND, 1, NULL);
428 if (!add)
429 mdev->when = jiffies + mdev->interval;
430 } else {
431 if (time_after(jiffies, maple_pnp_time))
432 /* Ensure we don't have block reads and devinfo
433 * calls interfering with one another - so flag the
434 * device as busy */
435 if (atomic_read(v: &mdev->busy) == 0) {
436 atomic_set(v: &mdev->busy, i: 1);
437 maple_add_packet(mdev, 0,
438 MAPLE_COMMAND_DEVINFO, 0, NULL);
439 }
440 }
441 return 0;
442}
443
444/* VBLANK bottom half - implemented via workqueue */
445static void maple_vblank_handler(struct work_struct *work)
446{
447 int x, locking;
448 struct maple_device *mdev;
449
450 if (!maple_dma_done())
451 return;
452
453 __raw_writel(val: 0, addr: MAPLE_ENABLE);
454
455 if (!list_empty(head: &maple_sentq))
456 goto finish;
457
458 /*
459 * Set up essential commands - to fetch data and
460 * check devices are still present
461 */
462 bus_for_each_dev(bus: &maple_bus_type, NULL, NULL,
463 fn: setup_maple_commands);
464
465 if (time_after(jiffies, maple_pnp_time)) {
466 /*
467 * Scan the empty ports - bus is flakey and may have
468 * mis-reported emptyness
469 */
470 for (x = 0; x < MAPLE_PORTS; x++) {
471 if (checked[x] && empty[x]) {
472 mdev = baseunits[x];
473 if (!mdev)
474 break;
475 atomic_set(v: &mdev->busy, i: 1);
476 locking = maple_add_packet(mdev, 0,
477 MAPLE_COMMAND_DEVINFO, 0, NULL);
478 if (!locking)
479 break;
480 }
481 }
482
483 maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL;
484 }
485
486finish:
487 maple_send();
488}
489
490/* handle devices added via hotplugs - placing them on queue for DEVINFO */
491static void maple_map_subunits(struct maple_device *mdev, int submask)
492{
493 int retval, k, devcheck;
494 struct maple_device *mdev_add;
495 struct maple_device_specify ds;
496
497 ds.port = mdev->port;
498 for (k = 0; k < 5; k++) {
499 ds.unit = k + 1;
500 retval =
501 bus_for_each_dev(bus: &maple_bus_type, NULL, data: &ds,
502 fn: check_maple_device);
503 if (retval) {
504 submask = submask >> 1;
505 continue;
506 }
507 devcheck = submask & 0x01;
508 if (devcheck) {
509 mdev_add = maple_alloc_dev(port: mdev->port, unit: k + 1);
510 if (!mdev_add)
511 return;
512 atomic_set(v: &mdev_add->busy, i: 1);
513 maple_add_packet(mdev_add, 0, MAPLE_COMMAND_DEVINFO,
514 0, NULL);
515 /* mark that we are checking sub devices */
516 scanning = 1;
517 }
518 submask = submask >> 1;
519 }
520}
521
522/* mark a device as removed */
523static void maple_clean_submap(struct maple_device *mdev)
524{
525 int killbit;
526
527 killbit = (mdev->unit > 0 ? (1 << (mdev->unit - 1)) & 0x1f : 0x20);
528 killbit = ~killbit;
529 killbit &= 0xFF;
530 subdevice_map[mdev->port] = subdevice_map[mdev->port] & killbit;
531}
532
533/* handle empty port or hotplug removal */
534static void maple_response_none(struct maple_device *mdev)
535{
536 maple_clean_submap(mdev);
537
538 if (likely(mdev->unit != 0)) {
539 /*
540 * Block devices play up
541 * and give the impression they have
542 * been removed even when still in place or
543 * trip the mtd layer when they have
544 * really gone - this code traps that eventuality
545 * and ensures we aren't overloaded with useless
546 * error messages
547 */
548 if (mdev->can_unload) {
549 if (!mdev->can_unload(mdev)) {
550 atomic_set(v: &mdev->busy, i: 2);
551 wake_up(&mdev->maple_wait);
552 return;
553 }
554 }
555
556 dev_info(&mdev->dev, "detaching device at (%d, %d)\n",
557 mdev->port, mdev->unit);
558 maple_detach_driver(mdev);
559 return;
560 } else {
561 if (!started || !fullscan) {
562 if (checked[mdev->port] == false) {
563 checked[mdev->port] = true;
564 empty[mdev->port] = true;
565 dev_info(&mdev->dev, "no devices"
566 " to port %d\n", mdev->port);
567 }
568 return;
569 }
570 }
571 /* Some hardware devices generate false detach messages on unit 0 */
572 atomic_set(v: &mdev->busy, i: 0);
573}
574
575/* preprocess hotplugs or scans */
576static void maple_response_devinfo(struct maple_device *mdev,
577 char *recvbuf)
578{
579 char submask;
580 if (!started || (scanning == 2) || !fullscan) {
581 if ((mdev->unit == 0) && (checked[mdev->port] == false)) {
582 checked[mdev->port] = true;
583 maple_attach_driver(mdev);
584 } else {
585 if (mdev->unit != 0)
586 maple_attach_driver(mdev);
587 if (mdev->unit == 0) {
588 empty[mdev->port] = false;
589 maple_attach_driver(mdev);
590 }
591 }
592 }
593 if (mdev->unit == 0) {
594 submask = recvbuf[2] & 0x1F;
595 if (submask ^ subdevice_map[mdev->port]) {
596 maple_map_subunits(mdev, submask);
597 subdevice_map[mdev->port] = submask;
598 }
599 }
600}
601
602static void maple_response_fileerr(struct maple_device *mdev, void *recvbuf)
603{
604 if (mdev->fileerr_handler) {
605 mdev->fileerr_handler(mdev, recvbuf);
606 return;
607 } else
608 dev_warn(&mdev->dev, "device at (%d, %d) reports"
609 "file error 0x%X\n", mdev->port, mdev->unit,
610 ((int *)recvbuf)[1]);
611}
612
613static void maple_port_rescan(void)
614{
615 int i;
616 struct maple_device *mdev;
617
618 fullscan = 1;
619 for (i = 0; i < MAPLE_PORTS; i++) {
620 if (checked[i] == false) {
621 fullscan = 0;
622 mdev = baseunits[i];
623 maple_add_packet(mdev, 0, MAPLE_COMMAND_DEVINFO,
624 0, NULL);
625 }
626 }
627}
628
629/* maple dma end bottom half - implemented via workqueue */
630static void maple_dma_handler(struct work_struct *work)
631{
632 struct mapleq *mq, *nmq;
633 struct maple_device *mdev;
634 char *recvbuf;
635 enum maple_code code;
636
637 if (!maple_dma_done())
638 return;
639 __raw_writel(val: 0, addr: MAPLE_ENABLE);
640 if (!list_empty(head: &maple_sentq)) {
641 list_for_each_entry_safe(mq, nmq, &maple_sentq, list) {
642 mdev = mq->dev;
643 recvbuf = mq->recvbuf->buf;
644 __flush_invalidate_region(sh_cacheop_vaddr(recvbuf),
645 0x400);
646 code = recvbuf[0];
647 kfree(objp: mq->sendbuf);
648 list_del_init(entry: &mq->list);
649 switch (code) {
650 case MAPLE_RESPONSE_NONE:
651 maple_response_none(mdev);
652 break;
653
654 case MAPLE_RESPONSE_DEVINFO:
655 maple_response_devinfo(mdev, recvbuf);
656 atomic_set(v: &mdev->busy, i: 0);
657 break;
658
659 case MAPLE_RESPONSE_DATATRF:
660 if (mdev->callback)
661 mdev->callback(mq);
662 atomic_set(v: &mdev->busy, i: 0);
663 wake_up(&mdev->maple_wait);
664 break;
665
666 case MAPLE_RESPONSE_FILEERR:
667 maple_response_fileerr(mdev, recvbuf);
668 atomic_set(v: &mdev->busy, i: 0);
669 wake_up(&mdev->maple_wait);
670 break;
671
672 case MAPLE_RESPONSE_AGAIN:
673 case MAPLE_RESPONSE_BADCMD:
674 case MAPLE_RESPONSE_BADFUNC:
675 dev_warn(&mdev->dev, "non-fatal error"
676 " 0x%X at (%d, %d)\n", code,
677 mdev->port, mdev->unit);
678 atomic_set(v: &mdev->busy, i: 0);
679 break;
680
681 case MAPLE_RESPONSE_ALLINFO:
682 dev_notice(&mdev->dev, "extended"
683 " device information request for (%d, %d)"
684 " but call is not supported\n", mdev->port,
685 mdev->unit);
686 atomic_set(v: &mdev->busy, i: 0);
687 break;
688
689 case MAPLE_RESPONSE_OK:
690 atomic_set(v: &mdev->busy, i: 0);
691 wake_up(&mdev->maple_wait);
692 break;
693
694 default:
695 break;
696 }
697 }
698 /* if scanning is 1 then we have subdevices to check */
699 if (scanning == 1) {
700 maple_send();
701 scanning = 2;
702 } else
703 scanning = 0;
704 /*check if we have actually tested all ports yet */
705 if (!fullscan)
706 maple_port_rescan();
707 /* mark that we have been through the first scan */
708 started = 1;
709 }
710 maple_send();
711}
712
713static irqreturn_t maple_dma_interrupt(int irq, void *dev_id)
714{
715 /* Load everything into the bottom half */
716 schedule_work(work: &maple_dma_process);
717 return IRQ_HANDLED;
718}
719
720static irqreturn_t maple_vblank_interrupt(int irq, void *dev_id)
721{
722 schedule_work(work: &maple_vblank_process);
723 return IRQ_HANDLED;
724}
725
726static int maple_set_dma_interrupt_handler(void)
727{
728 return request_irq(irq: HW_EVENT_MAPLE_DMA, handler: maple_dma_interrupt,
729 IRQF_SHARED, name: "maple bus DMA", dev: &maple_unsupported_device);
730}
731
732static int maple_set_vblank_interrupt_handler(void)
733{
734 return request_irq(irq: HW_EVENT_VSYNC, handler: maple_vblank_interrupt,
735 IRQF_SHARED, name: "maple bus VBLANK", dev: &maple_unsupported_device);
736}
737
738static int maple_get_dma_buffer(void)
739{
740 maple_sendbuf =
741 (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
742 MAPLE_DMA_PAGES);
743 if (!maple_sendbuf)
744 return -ENOMEM;
745 return 0;
746}
747
748static int maple_match_bus_driver(struct device *devptr,
749 struct device_driver *drvptr)
750{
751 struct maple_driver *maple_drv = to_maple_driver(drvptr);
752 struct maple_device *maple_dev = to_maple_dev(devptr);
753
754 /* Trap empty port case */
755 if (maple_dev->devinfo.function == 0xFFFFFFFF)
756 return 0;
757 else if (maple_dev->devinfo.function &
758 cpu_to_be32(maple_drv->function))
759 return 1;
760 return 0;
761}
762
763static void maple_bus_release(struct device *dev)
764{
765}
766
767static struct maple_driver maple_unsupported_device = {
768 .drv = {
769 .name = "maple_unsupported_device",
770 .bus = &maple_bus_type,
771 },
772};
773/*
774 * maple_bus_type - core maple bus structure
775 */
776struct bus_type maple_bus_type = {
777 .name = "maple",
778 .match = maple_match_bus_driver,
779};
780EXPORT_SYMBOL_GPL(maple_bus_type);
781
782static struct device maple_bus = {
783 .init_name = "maple",
784 .release = maple_bus_release,
785};
786
787static int __init maple_bus_init(void)
788{
789 int retval, i;
790 struct maple_device *mdev[MAPLE_PORTS];
791
792 __raw_writel(val: 0, addr: MAPLE_ENABLE);
793
794 retval = device_register(dev: &maple_bus);
795 if (retval)
796 goto cleanup;
797
798 retval = bus_register(bus: &maple_bus_type);
799 if (retval)
800 goto cleanup_device;
801
802 retval = driver_register(drv: &maple_unsupported_device.drv);
803 if (retval)
804 goto cleanup_bus;
805
806 /* allocate memory for maple bus dma */
807 retval = maple_get_dma_buffer();
808 if (retval) {
809 dev_err(&maple_bus, "failed to allocate DMA buffers\n");
810 goto cleanup_basic;
811 }
812
813 /* set up DMA interrupt handler */
814 retval = maple_set_dma_interrupt_handler();
815 if (retval) {
816 dev_err(&maple_bus, "bus failed to grab maple "
817 "DMA IRQ\n");
818 goto cleanup_dma;
819 }
820
821 /* set up VBLANK interrupt handler */
822 retval = maple_set_vblank_interrupt_handler();
823 if (retval) {
824 dev_err(&maple_bus, "bus failed to grab VBLANK IRQ\n");
825 goto cleanup_irq;
826 }
827
828 maple_queue_cache = KMEM_CACHE(maple_buffer, SLAB_HWCACHE_ALIGN);
829
830 if (!maple_queue_cache) {
831 retval = -ENOMEM;
832 goto cleanup_bothirqs;
833 }
834
835 INIT_LIST_HEAD(list: &maple_waitq);
836 INIT_LIST_HEAD(list: &maple_sentq);
837
838 /* setup maple ports */
839 for (i = 0; i < MAPLE_PORTS; i++) {
840 checked[i] = false;
841 empty[i] = false;
842 mdev[i] = maple_alloc_dev(port: i, unit: 0);
843 if (!mdev[i]) {
844 while (i-- > 0)
845 maple_free_dev(mdev: mdev[i]);
846 retval = -ENOMEM;
847 goto cleanup_cache;
848 }
849 baseunits[i] = mdev[i];
850 atomic_set(v: &mdev[i]->busy, i: 1);
851 maple_add_packet(mdev[i], 0, MAPLE_COMMAND_DEVINFO, 0, NULL);
852 subdevice_map[i] = 0;
853 }
854
855 maple_pnp_time = jiffies + HZ;
856 /* prepare initial queue */
857 maple_send();
858 dev_info(&maple_bus, "bus core now registered\n");
859
860 return 0;
861
862cleanup_cache:
863 kmem_cache_destroy(s: maple_queue_cache);
864
865cleanup_bothirqs:
866 free_irq(HW_EVENT_VSYNC, 0);
867
868cleanup_irq:
869 free_irq(HW_EVENT_MAPLE_DMA, 0);
870
871cleanup_dma:
872 free_pages(addr: (unsigned long) maple_sendbuf, order: MAPLE_DMA_PAGES);
873
874cleanup_basic:
875 driver_unregister(drv: &maple_unsupported_device.drv);
876
877cleanup_bus:
878 bus_unregister(bus: &maple_bus_type);
879
880cleanup_device:
881 device_unregister(dev: &maple_bus);
882
883cleanup:
884 printk(KERN_ERR "Maple bus registration failed\n");
885 return retval;
886}
887/* Push init to later to ensure hardware gets detected */
888fs_initcall(maple_bus_init);
889

source code of linux/drivers/sh/maple/maple.c