ia64/linux-2.6.18-xen.hg

view drivers/macintosh/adb.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
1 /*
2 * Device driver for the Apple Desktop Bus
3 * and the /dev/adb device on macintoshes.
4 *
5 * Copyright (C) 1996 Paul Mackerras.
6 *
7 * Modified to declare controllers as structures, added
8 * client notification of bus reset and handles PowerBook
9 * sleep, by Benjamin Herrenschmidt.
10 *
11 * To do:
12 *
13 * - /sys/bus/adb to list the devices and infos
14 * - more /dev/adb to allow userland to receive the
15 * flow of auto-polling datas from a given device.
16 * - move bus probe to a kernel thread
17 */
19 #include <linux/types.h>
20 #include <linux/errno.h>
21 #include <linux/kernel.h>
22 #include <linux/slab.h>
23 #include <linux/module.h>
24 #include <linux/fs.h>
25 #include <linux/mm.h>
26 #include <linux/sched.h>
27 #include <linux/smp_lock.h>
28 #include <linux/adb.h>
29 #include <linux/cuda.h>
30 #include <linux/pmu.h>
31 #include <linux/notifier.h>
32 #include <linux/wait.h>
33 #include <linux/init.h>
34 #include <linux/delay.h>
35 #include <linux/spinlock.h>
36 #include <linux/completion.h>
37 #include <linux/device.h>
39 #include <asm/uaccess.h>
40 #include <asm/semaphore.h>
41 #ifdef CONFIG_PPC
42 #include <asm/prom.h>
43 #include <asm/machdep.h>
44 #endif
47 EXPORT_SYMBOL(adb_controller);
48 EXPORT_SYMBOL(adb_client_list);
50 extern struct adb_driver via_macii_driver;
51 extern struct adb_driver via_maciisi_driver;
52 extern struct adb_driver via_cuda_driver;
53 extern struct adb_driver adb_iop_driver;
54 extern struct adb_driver via_pmu_driver;
55 extern struct adb_driver macio_adb_driver;
57 static struct adb_driver *adb_driver_list[] = {
58 #ifdef CONFIG_ADB_MACII
59 &via_macii_driver,
60 #endif
61 #ifdef CONFIG_ADB_MACIISI
62 &via_maciisi_driver,
63 #endif
64 #ifdef CONFIG_ADB_CUDA
65 &via_cuda_driver,
66 #endif
67 #ifdef CONFIG_ADB_IOP
68 &adb_iop_driver,
69 #endif
70 #if defined(CONFIG_ADB_PMU) || defined(CONFIG_ADB_PMU68K)
71 &via_pmu_driver,
72 #endif
73 #ifdef CONFIG_ADB_MACIO
74 &macio_adb_driver,
75 #endif
76 NULL
77 };
79 static struct class *adb_dev_class;
81 struct adb_driver *adb_controller;
82 BLOCKING_NOTIFIER_HEAD(adb_client_list);
83 static int adb_got_sleep;
84 static int adb_inited;
85 static pid_t adb_probe_task_pid;
86 static DECLARE_MUTEX(adb_probe_mutex);
87 static struct completion adb_probe_task_comp;
88 static int sleepy_trackpad;
89 static int autopoll_devs;
90 int __adb_probe_sync;
92 #ifdef CONFIG_PM
93 static int adb_notify_sleep(struct pmu_sleep_notifier *self, int when);
94 static struct pmu_sleep_notifier adb_sleep_notifier = {
95 adb_notify_sleep,
96 SLEEP_LEVEL_ADB,
97 };
98 #endif
100 static int adb_scan_bus(void);
101 static int do_adb_reset_bus(void);
102 static void adbdev_init(void);
103 static int try_handler_change(int, int);
105 static struct adb_handler {
106 void (*handler)(unsigned char *, int, struct pt_regs *, int);
107 int original_address;
108 int handler_id;
109 int busy;
110 } adb_handler[16];
112 /*
113 * The adb_handler_sem mutex protects all accesses to the original_address
114 * and handler_id fields of adb_handler[i] for all i, and changes to the
115 * handler field.
116 * Accesses to the handler field are protected by the adb_handler_lock
117 * rwlock. It is held across all calls to any handler, so that by the
118 * time adb_unregister returns, we know that the old handler isn't being
119 * called.
120 */
121 static DECLARE_MUTEX(adb_handler_sem);
122 static DEFINE_RWLOCK(adb_handler_lock);
124 #if 0
125 static void printADBreply(struct adb_request *req)
126 {
127 int i;
129 printk("adb reply (%d)", req->reply_len);
130 for(i = 0; i < req->reply_len; i++)
131 printk(" %x", req->reply[i]);
132 printk("\n");
134 }
135 #endif
138 static __inline__ void adb_wait_ms(unsigned int ms)
139 {
140 if (current->pid && adb_probe_task_pid &&
141 adb_probe_task_pid == current->pid)
142 msleep(ms);
143 else
144 mdelay(ms);
145 }
147 static int adb_scan_bus(void)
148 {
149 int i, highFree=0, noMovement;
150 int devmask = 0;
151 struct adb_request req;
153 /* assumes adb_handler[] is all zeroes at this point */
154 for (i = 1; i < 16; i++) {
155 /* see if there is anything at address i */
156 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
157 (i << 4) | 0xf);
158 if (req.reply_len > 1)
159 /* one or more devices at this address */
160 adb_handler[i].original_address = i;
161 else if (i > highFree)
162 highFree = i;
163 }
165 /* Note we reset noMovement to 0 each time we move a device */
166 for (noMovement = 1; noMovement < 2 && highFree > 0; noMovement++) {
167 for (i = 1; i < 16; i++) {
168 if (adb_handler[i].original_address == 0)
169 continue;
170 /*
171 * Send a "talk register 3" command to address i
172 * to provoke a collision if there is more than
173 * one device at this address.
174 */
175 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
176 (i << 4) | 0xf);
177 /*
178 * Move the device(s) which didn't detect a
179 * collision to address `highFree'. Hopefully
180 * this only moves one device.
181 */
182 adb_request(&req, NULL, ADBREQ_SYNC, 3,
183 (i<< 4) | 0xb, (highFree | 0x60), 0xfe);
184 /*
185 * See if anybody actually moved. This is suggested
186 * by HW TechNote 01:
187 *
188 * http://developer.apple.com/technotes/hw/hw_01.html
189 */
190 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
191 (highFree << 4) | 0xf);
192 if (req.reply_len <= 1) continue;
193 /*
194 * Test whether there are any device(s) left
195 * at address i.
196 */
197 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
198 (i << 4) | 0xf);
199 if (req.reply_len > 1) {
200 /*
201 * There are still one or more devices
202 * left at address i. Register the one(s)
203 * we moved to `highFree', and find a new
204 * value for highFree.
205 */
206 adb_handler[highFree].original_address =
207 adb_handler[i].original_address;
208 while (highFree > 0 &&
209 adb_handler[highFree].original_address)
210 highFree--;
211 if (highFree <= 0)
212 break;
214 noMovement = 0;
215 }
216 else {
217 /*
218 * No devices left at address i; move the
219 * one(s) we moved to `highFree' back to i.
220 */
221 adb_request(&req, NULL, ADBREQ_SYNC, 3,
222 (highFree << 4) | 0xb,
223 (i | 0x60), 0xfe);
224 }
225 }
226 }
228 /* Now fill in the handler_id field of the adb_handler entries. */
229 printk(KERN_DEBUG "adb devices:");
230 for (i = 1; i < 16; i++) {
231 if (adb_handler[i].original_address == 0)
232 continue;
233 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
234 (i << 4) | 0xf);
235 adb_handler[i].handler_id = req.reply[2];
236 printk(" [%d]: %d %x", i, adb_handler[i].original_address,
237 adb_handler[i].handler_id);
238 devmask |= 1 << i;
239 }
240 printk("\n");
241 return devmask;
242 }
244 /*
245 * This kernel task handles ADB probing. It dies once probing is
246 * completed.
247 */
248 static int
249 adb_probe_task(void *x)
250 {
251 sigset_t blocked;
253 strcpy(current->comm, "kadbprobe");
255 sigfillset(&blocked);
256 sigprocmask(SIG_BLOCK, &blocked, NULL);
257 flush_signals(current);
259 printk(KERN_INFO "adb: starting probe task...\n");
260 do_adb_reset_bus();
261 printk(KERN_INFO "adb: finished probe task...\n");
263 adb_probe_task_pid = 0;
264 up(&adb_probe_mutex);
266 return 0;
267 }
269 static void
270 __adb_probe_task(void *data)
271 {
272 adb_probe_task_pid = kernel_thread(adb_probe_task, NULL, SIGCHLD | CLONE_KERNEL);
273 }
275 static DECLARE_WORK(adb_reset_work, __adb_probe_task, NULL);
277 int
278 adb_reset_bus(void)
279 {
280 if (__adb_probe_sync) {
281 do_adb_reset_bus();
282 return 0;
283 }
285 down(&adb_probe_mutex);
286 schedule_work(&adb_reset_work);
287 return 0;
288 }
290 int __init adb_init(void)
291 {
292 struct adb_driver *driver;
293 int i;
295 #ifdef CONFIG_PPC32
296 if (!machine_is(chrp) && !machine_is(powermac))
297 return 0;
298 #endif
299 #ifdef CONFIG_MAC
300 if (!MACH_IS_MAC)
301 return 0;
302 #endif
304 /* xmon may do early-init */
305 if (adb_inited)
306 return 0;
307 adb_inited = 1;
309 adb_controller = NULL;
311 i = 0;
312 while ((driver = adb_driver_list[i++]) != NULL) {
313 if (!driver->probe()) {
314 adb_controller = driver;
315 break;
316 }
317 }
318 if ((adb_controller == NULL) || adb_controller->init()) {
319 printk(KERN_WARNING "Warning: no ADB interface detected\n");
320 adb_controller = NULL;
321 } else {
322 #ifdef CONFIG_PM
323 pmu_register_sleep_notifier(&adb_sleep_notifier);
324 #endif /* CONFIG_PM */
325 #ifdef CONFIG_PPC
326 if (machine_is_compatible("AAPL,PowerBook1998") ||
327 machine_is_compatible("PowerBook1,1"))
328 sleepy_trackpad = 1;
329 #endif /* CONFIG_PPC */
330 init_completion(&adb_probe_task_comp);
331 adbdev_init();
332 adb_reset_bus();
333 }
334 return 0;
335 }
337 __initcall(adb_init);
339 #ifdef CONFIG_PM
340 /*
341 * notify clients before sleep and reset bus afterwards
342 */
343 int
344 adb_notify_sleep(struct pmu_sleep_notifier *self, int when)
345 {
346 int ret;
348 switch (when) {
349 case PBOOK_SLEEP_REQUEST:
350 adb_got_sleep = 1;
351 /* We need to get a lock on the probe thread */
352 down(&adb_probe_mutex);
353 /* Stop autopoll */
354 if (adb_controller->autopoll)
355 adb_controller->autopoll(0);
356 ret = blocking_notifier_call_chain(&adb_client_list,
357 ADB_MSG_POWERDOWN, NULL);
358 if (ret & NOTIFY_STOP_MASK) {
359 up(&adb_probe_mutex);
360 return PBOOK_SLEEP_REFUSE;
361 }
362 break;
363 case PBOOK_SLEEP_REJECT:
364 if (adb_got_sleep) {
365 adb_got_sleep = 0;
366 up(&adb_probe_mutex);
367 adb_reset_bus();
368 }
369 break;
371 case PBOOK_SLEEP_NOW:
372 break;
373 case PBOOK_WAKE:
374 adb_got_sleep = 0;
375 up(&adb_probe_mutex);
376 adb_reset_bus();
377 break;
378 }
379 return PBOOK_SLEEP_OK;
380 }
381 #endif /* CONFIG_PM */
383 static int
384 do_adb_reset_bus(void)
385 {
386 int ret, nret;
388 if (adb_controller == NULL)
389 return -ENXIO;
391 if (adb_controller->autopoll)
392 adb_controller->autopoll(0);
394 nret = blocking_notifier_call_chain(&adb_client_list,
395 ADB_MSG_PRE_RESET, NULL);
396 if (nret & NOTIFY_STOP_MASK) {
397 if (adb_controller->autopoll)
398 adb_controller->autopoll(autopoll_devs);
399 return -EBUSY;
400 }
402 if (sleepy_trackpad) {
403 /* Let the trackpad settle down */
404 adb_wait_ms(500);
405 }
407 down(&adb_handler_sem);
408 write_lock_irq(&adb_handler_lock);
409 memset(adb_handler, 0, sizeof(adb_handler));
410 write_unlock_irq(&adb_handler_lock);
412 /* That one is still a bit synchronous, oh well... */
413 if (adb_controller->reset_bus)
414 ret = adb_controller->reset_bus();
415 else
416 ret = 0;
418 if (sleepy_trackpad) {
419 /* Let the trackpad settle down */
420 adb_wait_ms(1500);
421 }
423 if (!ret) {
424 autopoll_devs = adb_scan_bus();
425 if (adb_controller->autopoll)
426 adb_controller->autopoll(autopoll_devs);
427 }
428 up(&adb_handler_sem);
430 nret = blocking_notifier_call_chain(&adb_client_list,
431 ADB_MSG_POST_RESET, NULL);
432 if (nret & NOTIFY_STOP_MASK)
433 return -EBUSY;
435 return ret;
436 }
438 void
439 adb_poll(void)
440 {
441 if ((adb_controller == NULL)||(adb_controller->poll == NULL))
442 return;
443 adb_controller->poll();
444 }
446 static void
447 adb_probe_wakeup(struct adb_request *req)
448 {
449 complete(&adb_probe_task_comp);
450 }
452 /* Static request used during probe */
453 static struct adb_request adb_sreq;
454 static unsigned long adb_sreq_lock; // Use semaphore ! */
456 int
457 adb_request(struct adb_request *req, void (*done)(struct adb_request *),
458 int flags, int nbytes, ...)
459 {
460 va_list list;
461 int i, use_sreq;
462 int rc;
464 if ((adb_controller == NULL) || (adb_controller->send_request == NULL))
465 return -ENXIO;
466 if (nbytes < 1)
467 return -EINVAL;
468 if (req == NULL && (flags & ADBREQ_NOSEND))
469 return -EINVAL;
471 if (req == NULL) {
472 if (test_and_set_bit(0,&adb_sreq_lock)) {
473 printk("adb.c: Warning: contention on static request !\n");
474 return -EPERM;
475 }
476 req = &adb_sreq;
477 flags |= ADBREQ_SYNC;
478 use_sreq = 1;
479 } else
480 use_sreq = 0;
481 req->nbytes = nbytes+1;
482 req->done = done;
483 req->reply_expected = flags & ADBREQ_REPLY;
484 req->data[0] = ADB_PACKET;
485 va_start(list, nbytes);
486 for (i = 0; i < nbytes; ++i)
487 req->data[i+1] = va_arg(list, int);
488 va_end(list);
490 if (flags & ADBREQ_NOSEND)
491 return 0;
493 /* Synchronous requests send from the probe thread cause it to
494 * block. Beware that the "done" callback will be overriden !
495 */
496 if ((flags & ADBREQ_SYNC) &&
497 (current->pid && adb_probe_task_pid &&
498 adb_probe_task_pid == current->pid)) {
499 req->done = adb_probe_wakeup;
500 rc = adb_controller->send_request(req, 0);
501 if (rc || req->complete)
502 goto bail;
503 wait_for_completion(&adb_probe_task_comp);
504 rc = 0;
505 goto bail;
506 }
508 rc = adb_controller->send_request(req, flags & ADBREQ_SYNC);
509 bail:
510 if (use_sreq)
511 clear_bit(0, &adb_sreq_lock);
513 return rc;
514 }
516 /* Ultimately this should return the number of devices with
517 the given default id.
518 And it does it now ! Note: changed behaviour: This function
519 will now register if default_id _and_ handler_id both match
520 but handler_id can be left to 0 to match with default_id only.
521 When handler_id is set, this function will try to adjust
522 the handler_id id it doesn't match. */
523 int
524 adb_register(int default_id, int handler_id, struct adb_ids *ids,
525 void (*handler)(unsigned char *, int, struct pt_regs *, int))
526 {
527 int i;
529 down(&adb_handler_sem);
530 ids->nids = 0;
531 for (i = 1; i < 16; i++) {
532 if ((adb_handler[i].original_address == default_id) &&
533 (!handler_id || (handler_id == adb_handler[i].handler_id) ||
534 try_handler_change(i, handler_id))) {
535 if (adb_handler[i].handler != 0) {
536 printk(KERN_ERR
537 "Two handlers for ADB device %d\n",
538 default_id);
539 continue;
540 }
541 write_lock_irq(&adb_handler_lock);
542 adb_handler[i].handler = handler;
543 write_unlock_irq(&adb_handler_lock);
544 ids->id[ids->nids++] = i;
545 }
546 }
547 up(&adb_handler_sem);
548 return ids->nids;
549 }
551 int
552 adb_unregister(int index)
553 {
554 int ret = -ENODEV;
556 down(&adb_handler_sem);
557 write_lock_irq(&adb_handler_lock);
558 if (adb_handler[index].handler) {
559 while(adb_handler[index].busy) {
560 write_unlock_irq(&adb_handler_lock);
561 yield();
562 write_lock_irq(&adb_handler_lock);
563 }
564 ret = 0;
565 adb_handler[index].handler = NULL;
566 }
567 write_unlock_irq(&adb_handler_lock);
568 up(&adb_handler_sem);
569 return ret;
570 }
572 void
573 adb_input(unsigned char *buf, int nb, struct pt_regs *regs, int autopoll)
574 {
575 int i, id;
576 static int dump_adb_input = 0;
577 unsigned long flags;
579 void (*handler)(unsigned char *, int, struct pt_regs *, int);
581 /* We skip keystrokes and mouse moves when the sleep process
582 * has been started. We stop autopoll, but this is another security
583 */
584 if (adb_got_sleep)
585 return;
587 id = buf[0] >> 4;
588 if (dump_adb_input) {
589 printk(KERN_INFO "adb packet: ");
590 for (i = 0; i < nb; ++i)
591 printk(" %x", buf[i]);
592 printk(", id = %d\n", id);
593 }
594 write_lock_irqsave(&adb_handler_lock, flags);
595 handler = adb_handler[id].handler;
596 if (handler != NULL)
597 adb_handler[id].busy = 1;
598 write_unlock_irqrestore(&adb_handler_lock, flags);
599 if (handler != NULL) {
600 (*handler)(buf, nb, regs, autopoll);
601 wmb();
602 adb_handler[id].busy = 0;
603 }
605 }
607 /* Try to change handler to new_id. Will return 1 if successful. */
608 static int try_handler_change(int address, int new_id)
609 {
610 struct adb_request req;
612 if (adb_handler[address].handler_id == new_id)
613 return 1;
614 adb_request(&req, NULL, ADBREQ_SYNC, 3,
615 ADB_WRITEREG(address, 3), address | 0x20, new_id);
616 adb_request(&req, NULL, ADBREQ_SYNC | ADBREQ_REPLY, 1,
617 ADB_READREG(address, 3));
618 if (req.reply_len < 2)
619 return 0;
620 if (req.reply[2] != new_id)
621 return 0;
622 adb_handler[address].handler_id = req.reply[2];
624 return 1;
625 }
627 int
628 adb_try_handler_change(int address, int new_id)
629 {
630 int ret;
632 down(&adb_handler_sem);
633 ret = try_handler_change(address, new_id);
634 up(&adb_handler_sem);
635 return ret;
636 }
638 int
639 adb_get_infos(int address, int *original_address, int *handler_id)
640 {
641 down(&adb_handler_sem);
642 *original_address = adb_handler[address].original_address;
643 *handler_id = adb_handler[address].handler_id;
644 up(&adb_handler_sem);
646 return (*original_address != 0);
647 }
650 /*
651 * /dev/adb device driver.
652 */
654 #define ADB_MAJOR 56 /* major number for /dev/adb */
656 struct adbdev_state {
657 spinlock_t lock;
658 atomic_t n_pending;
659 struct adb_request *completed;
660 wait_queue_head_t wait_queue;
661 int inuse;
662 };
664 static void adb_write_done(struct adb_request *req)
665 {
666 struct adbdev_state *state = (struct adbdev_state *) req->arg;
667 unsigned long flags;
669 if (!req->complete) {
670 req->reply_len = 0;
671 req->complete = 1;
672 }
673 spin_lock_irqsave(&state->lock, flags);
674 atomic_dec(&state->n_pending);
675 if (!state->inuse) {
676 kfree(req);
677 if (atomic_read(&state->n_pending) == 0) {
678 spin_unlock_irqrestore(&state->lock, flags);
679 kfree(state);
680 return;
681 }
682 } else {
683 struct adb_request **ap = &state->completed;
684 while (*ap != NULL)
685 ap = &(*ap)->next;
686 req->next = NULL;
687 *ap = req;
688 wake_up_interruptible(&state->wait_queue);
689 }
690 spin_unlock_irqrestore(&state->lock, flags);
691 }
693 static int
694 do_adb_query(struct adb_request *req)
695 {
696 int ret = -EINVAL;
698 switch(req->data[1])
699 {
700 case ADB_QUERY_GETDEVINFO:
701 if (req->nbytes < 3)
702 break;
703 down(&adb_handler_sem);
704 req->reply[0] = adb_handler[req->data[2]].original_address;
705 req->reply[1] = adb_handler[req->data[2]].handler_id;
706 up(&adb_handler_sem);
707 req->complete = 1;
708 req->reply_len = 2;
709 adb_write_done(req);
710 ret = 0;
711 break;
712 }
713 return ret;
714 }
716 static int adb_open(struct inode *inode, struct file *file)
717 {
718 struct adbdev_state *state;
720 if (iminor(inode) > 0 || adb_controller == NULL)
721 return -ENXIO;
722 state = kmalloc(sizeof(struct adbdev_state), GFP_KERNEL);
723 if (state == 0)
724 return -ENOMEM;
725 file->private_data = state;
726 spin_lock_init(&state->lock);
727 atomic_set(&state->n_pending, 0);
728 state->completed = NULL;
729 init_waitqueue_head(&state->wait_queue);
730 state->inuse = 1;
732 return 0;
733 }
735 static int adb_release(struct inode *inode, struct file *file)
736 {
737 struct adbdev_state *state = file->private_data;
738 unsigned long flags;
740 lock_kernel();
741 if (state) {
742 file->private_data = NULL;
743 spin_lock_irqsave(&state->lock, flags);
744 if (atomic_read(&state->n_pending) == 0
745 && state->completed == NULL) {
746 spin_unlock_irqrestore(&state->lock, flags);
747 kfree(state);
748 } else {
749 state->inuse = 0;
750 spin_unlock_irqrestore(&state->lock, flags);
751 }
752 }
753 unlock_kernel();
754 return 0;
755 }
757 static ssize_t adb_read(struct file *file, char __user *buf,
758 size_t count, loff_t *ppos)
759 {
760 int ret = 0;
761 struct adbdev_state *state = file->private_data;
762 struct adb_request *req;
763 wait_queue_t wait = __WAITQUEUE_INITIALIZER(wait,current);
764 unsigned long flags;
766 if (count < 2)
767 return -EINVAL;
768 if (count > sizeof(req->reply))
769 count = sizeof(req->reply);
770 if (!access_ok(VERIFY_WRITE, buf, count))
771 return -EFAULT;
773 req = NULL;
774 spin_lock_irqsave(&state->lock, flags);
775 add_wait_queue(&state->wait_queue, &wait);
776 current->state = TASK_INTERRUPTIBLE;
778 for (;;) {
779 req = state->completed;
780 if (req != NULL)
781 state->completed = req->next;
782 else if (atomic_read(&state->n_pending) == 0)
783 ret = -EIO;
784 if (req != NULL || ret != 0)
785 break;
787 if (file->f_flags & O_NONBLOCK) {
788 ret = -EAGAIN;
789 break;
790 }
791 if (signal_pending(current)) {
792 ret = -ERESTARTSYS;
793 break;
794 }
795 spin_unlock_irqrestore(&state->lock, flags);
796 schedule();
797 spin_lock_irqsave(&state->lock, flags);
798 }
800 current->state = TASK_RUNNING;
801 remove_wait_queue(&state->wait_queue, &wait);
802 spin_unlock_irqrestore(&state->lock, flags);
804 if (ret)
805 return ret;
807 ret = req->reply_len;
808 if (ret > count)
809 ret = count;
810 if (ret > 0 && copy_to_user(buf, req->reply, ret))
811 ret = -EFAULT;
813 kfree(req);
814 return ret;
815 }
817 static ssize_t adb_write(struct file *file, const char __user *buf,
818 size_t count, loff_t *ppos)
819 {
820 int ret/*, i*/;
821 struct adbdev_state *state = file->private_data;
822 struct adb_request *req;
824 if (count < 2 || count > sizeof(req->data))
825 return -EINVAL;
826 if (adb_controller == NULL)
827 return -ENXIO;
828 if (!access_ok(VERIFY_READ, buf, count))
829 return -EFAULT;
831 req = (struct adb_request *) kmalloc(sizeof(struct adb_request),
832 GFP_KERNEL);
833 if (req == NULL)
834 return -ENOMEM;
836 req->nbytes = count;
837 req->done = adb_write_done;
838 req->arg = (void *) state;
839 req->complete = 0;
841 ret = -EFAULT;
842 if (copy_from_user(req->data, buf, count))
843 goto out;
845 atomic_inc(&state->n_pending);
847 /* If a probe is in progress or we are sleeping, wait for it to complete */
848 down(&adb_probe_mutex);
850 /* Queries are special requests sent to the ADB driver itself */
851 if (req->data[0] == ADB_QUERY) {
852 if (count > 1)
853 ret = do_adb_query(req);
854 else
855 ret = -EINVAL;
856 up(&adb_probe_mutex);
857 }
858 /* Special case for ADB_BUSRESET request, all others are sent to
859 the controller */
860 else if ((req->data[0] == ADB_PACKET)&&(count > 1)
861 &&(req->data[1] == ADB_BUSRESET)) {
862 ret = do_adb_reset_bus();
863 up(&adb_probe_mutex);
864 atomic_dec(&state->n_pending);
865 if (ret == 0)
866 ret = count;
867 goto out;
868 } else {
869 req->reply_expected = ((req->data[1] & 0xc) == 0xc);
870 if (adb_controller && adb_controller->send_request)
871 ret = adb_controller->send_request(req, 0);
872 else
873 ret = -ENXIO;
874 up(&adb_probe_mutex);
875 }
877 if (ret != 0) {
878 atomic_dec(&state->n_pending);
879 goto out;
880 }
881 return count;
883 out:
884 kfree(req);
885 return ret;
886 }
888 static struct file_operations adb_fops = {
889 .owner = THIS_MODULE,
890 .llseek = no_llseek,
891 .read = adb_read,
892 .write = adb_write,
893 .open = adb_open,
894 .release = adb_release,
895 };
897 static void
898 adbdev_init(void)
899 {
900 if (register_chrdev(ADB_MAJOR, "adb", &adb_fops)) {
901 printk(KERN_ERR "adb: unable to get major %d\n", ADB_MAJOR);
902 return;
903 }
905 adb_dev_class = class_create(THIS_MODULE, "adb");
906 if (IS_ERR(adb_dev_class))
907 return;
908 class_device_create(adb_dev_class, NULL, MKDEV(ADB_MAJOR, 0), NULL, "adb");
909 }