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# system call top
# (c) 2010, Tom Zanussi <tzanussi@gmail.com>
# Licensed under the terms of the GNU GPL License version 2
#
# Periodically displays system-wide system call totals, broken down by
# syscall.  If a [comm] arg is specified, only syscalls called by
# [comm] are displayed. If an [interval] arg is specified, the display
# will be refreshed every [interval] seconds.  The default interval is
# 3 seconds.

import os, sys, thread, time

sys.path.append(os.environ['PERF_EXEC_PATH'] + \
	'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')

from perf_trace_context import *
from Core import *
from Util import *

usage = "perf script -s sctop.py [comm] [interval]\n";

for_comm = None
default_interval = 3
interval = default_interval

if len(sys.argv) > 3:
	sys.exit(usage)

if len(sys.argv) > 2:
	for_comm = sys.argv[1]
	interval = int(sys.argv[2])
elif len(sys.argv) > 1:
	try:
		interval = int(sys.argv[1])
	except ValueError:
		for_comm = sys.argv[1]
		interval = default_interval

syscalls = autodict()

def trace_begin():
	thread.start_new_thread(print_syscall_totals, (interval,))
	pass

def raw_syscalls__sys_enter(event_name, context, common_cpu,
	common_secs, common_nsecs, common_pid, common_comm,
	common_callchain, id, args):
	if for_comm is not None:
		if common_comm != for_comm:
			return
	try:
		syscalls[id] += 1
	except TypeError:
		syscalls[id] = 1

def syscalls__sys_enter(event_name, context, common_cpu,
	common_secs, common_nsecs, common_pid, common_comm,
	id, args):
	raw_syscalls__sys_enter(**locals())

def print_syscall_totals(interval):
	while 1:
		clear_term()
		if for_comm is not None:
			print "\nsyscall events for %s:\n\n" % (for_comm),
		else:
			print "\nsyscall events:\n\n",

		print "%-40s  %10s\n" % ("event", "count"),
		print "%-40s  %10s\n" % ("----------------------------------------", \
						 "----------"),

		for id, val in sorted(syscalls.iteritems(), key = lambda(k, v): (v, k), \
					      reverse = True):
			try:
				print "%-40s  %10d\n" % (syscall_name(id), val),
			except TypeError:
				pass
		syscalls.clear()
		time.sleep(interval)
76' href='#n376'>376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900
/*
 *  Initialization routines
 *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <sound/driver.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/file.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/ctype.h>
#include <linux/pci.h>
#include <linux/pm.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/info.h>

struct snd_shutdown_f_ops {
	struct file_operations f_ops;
	struct snd_shutdown_f_ops *next;
};

unsigned int snd_cards_lock = 0;	/* locked for registering/using */
snd_card_t *snd_cards[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = NULL};
DEFINE_RWLOCK(snd_card_rwlock);

#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
int (*snd_mixer_oss_notify_callback)(snd_card_t *card, int free_flag);
#endif

static void snd_card_id_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
{
	snd_iprintf(buffer, "%s\n", entry->card->id);
}

static void snd_card_free_thread(void * __card);

/**
 *  snd_card_new - create and initialize a soundcard structure
 *  @idx: card index (address) [0 ... (SNDRV_CARDS-1)]
 *  @xid: card identification (ASCII string)
 *  @module: top level module for locking
 *  @extra_size: allocate this extra size after the main soundcard structure
 *
 *  Creates and initializes a soundcard structure.
 *
 *  Returns kmallocated snd_card_t structure. Creates the ALSA control interface
 *  (which is blocked until snd_card_register function is called).
 */
snd_card_t *snd_card_new(int idx, const char *xid,
			 struct module *module, int extra_size)
{
	snd_card_t *card;
	int err;

	if (extra_size < 0)
		extra_size = 0;
	card = kzalloc(sizeof(*card) + extra_size, GFP_KERNEL);
	if (card == NULL)
		return NULL;
	if (xid) {
		if (!snd_info_check_reserved_words(xid))
			goto __error;
		strlcpy(card->id, xid, sizeof(card->id));
	}
	err = 0;
	write_lock(&snd_card_rwlock);
	if (idx < 0) {
		int idx2;
		for (idx2 = 0; idx2 < SNDRV_CARDS; idx2++)
			if (~snd_cards_lock & idx & 1<<idx2) {
				idx = idx2;
				if (idx >= snd_ecards_limit)
					snd_ecards_limit = idx + 1;
				break;
			}
	} else if (idx < snd_ecards_limit) {
		if (snd_cards_lock & (1 << idx))
			err = -ENODEV;	/* invalid */
	} else if (idx < SNDRV_CARDS)
		snd_ecards_limit = idx + 1; /* increase the limit */
	else
		err = -ENODEV;
	if (idx < 0 || err < 0) {
		write_unlock(&snd_card_rwlock);
		snd_printk(KERN_ERR "cannot find the slot for index %d (range 0-%i)\n", idx, snd_ecards_limit - 1);
		goto __error;
	}
	snd_cards_lock |= 1 << idx;		/* lock it */
	write_unlock(&snd_card_rwlock);
	card->number = idx;
	card->module = module;
	INIT_LIST_HEAD(&card->devices);
	init_rwsem(&card->controls_rwsem);
	rwlock_init(&card->ctl_files_rwlock);
	INIT_LIST_HEAD(&card->controls);
	INIT_LIST_HEAD(&card->ctl_files);
	spin_lock_init(&card->files_lock);
	init_waitqueue_head(&card->shutdown_sleep);
	INIT_WORK(&card->free_workq, snd_card_free_thread, card);
#ifdef CONFIG_PM
	init_MUTEX(&card->power_lock);
	init_waitqueue_head(&card->power_sleep);
#endif
	/* the control interface cannot be accessed from the user space until */
	/* snd_cards_bitmask and snd_cards are set with snd_card_register */
	if ((err = snd_ctl_create(card)) < 0) {
		snd_printd("unable to register control minors\n");
		goto __error;
	}
	if ((err = snd_info_card_create(card)) < 0) {
		snd_printd("unable to create card info\n");
		goto __error_ctl;
	}
	if (extra_size > 0)
		card->private_data = (char *)card + sizeof(snd_card_t);
	return card;

      __error_ctl:
	snd_device_free_all(card, SNDRV_DEV_CMD_PRE);
      __error:
	kfree(card);
      	return NULL;
}

static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
{
	return POLLERR | POLLNVAL;
}

/**
 *  snd_card_disconnect - disconnect all APIs from the file-operations (user space)
 *  @card: soundcard structure
 *
 *  Disconnects all APIs from the file-operations (user space).
 *
 *  Returns zero, otherwise a negative error code.
 *
 *  Note: The current implementation replaces all active file->f_op with special
 *        dummy file operations (they do nothing except release).
 */
int snd_card_disconnect(snd_card_t * card)
{
	struct snd_monitor_file *mfile;
	struct file *file;
	struct snd_shutdown_f_ops *s_f_ops;
	struct file_operations *f_ops, *old_f_ops;
	int err;

	spin_lock(&card->files_lock);
	if (card->shutdown) {
		spin_unlock(&card->files_lock);
		return 0;
	}
	card->shutdown = 1;
	spin_unlock(&card->files_lock);

	/* phase 1: disable fops (user space) operations for ALSA API */
	write_lock(&snd_card_rwlock);
	snd_cards[card->number] = NULL;
	write_unlock(&snd_card_rwlock);
	
	/* phase 2: replace file->f_op with special dummy operations */
	
	spin_lock(&card->files_lock);
	mfile = card->files;
	while (mfile) {
		file = mfile->file;

		/* it's critical part, use endless loop */
		/* we have no room to fail */
		s_f_ops = kmalloc(sizeof(struct snd_shutdown_f_ops), GFP_ATOMIC);
		if (s_f_ops == NULL)
			panic("Atomic allocation failed for snd_shutdown_f_ops!");

		f_ops = &s_f_ops->f_ops;

		memset(f_ops, 0, sizeof(*f_ops));
		f_ops->owner = file->f_op->owner;
		f_ops->release = file->f_op->release;
		f_ops->poll = snd_disconnect_poll;

		s_f_ops->next = card->s_f_ops;
		card->s_f_ops = s_f_ops;
		
		f_ops = fops_get(f_ops);

		old_f_ops = file->f_op;
		file->f_op = f_ops;	/* must be atomic */
		fops_put(old_f_ops);
		
		mfile = mfile->next;
	}
	spin_unlock(&card->files_lock);	

	/* phase 3: notify all connected devices about disconnection */
	/* at this point, they cannot respond to any calls except release() */

#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
	if (snd_mixer_oss_notify_callback)
		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_DISCONNECT);
#endif

	/* notify all devices that we are disconnected */
	err = snd_device_disconnect_all(card);
	if (err < 0)
		snd_printk(KERN_ERR "not all devices for card %i can be disconnected\n", card->number);

	return 0;	
}

#ifdef CONFIG_SND_GENERIC_DRIVER
static void snd_generic_device_unregister(snd_card_t *card);
#else
#define snd_generic_device_unregister(x) /*NOP*/
#endif

/**
 *  snd_card_free - frees given soundcard structure
 *  @card: soundcard structure
 *
 *  This function releases the soundcard structure and the all assigned
 *  devices automatically.  That is, you don't have to release the devices
 *  by yourself.
 *
 *  Returns zero. Frees all associated devices and frees the control
 *  interface associated to given soundcard.
 */
int snd_card_free(snd_card_t * card)
{
	struct snd_shutdown_f_ops *s_f_ops;

	if (card == NULL)
		return -EINVAL;
	write_lock(&snd_card_rwlock);
	snd_cards[card->number] = NULL;
	write_unlock(&snd_card_rwlock);

#ifdef CONFIG_PM
	wake_up(&card->power_sleep);
#endif
	/* wait, until all devices are ready for the free operation */
	wait_event(card->shutdown_sleep, card->files == NULL);

#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
	if (snd_mixer_oss_notify_callback)
		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_FREE);
#endif
	if (snd_device_free_all(card, SNDRV_DEV_CMD_PRE) < 0) {
		snd_printk(KERN_ERR "unable to free all devices (pre)\n");
		/* Fatal, but this situation should never occur */
	}
	if (snd_device_free_all(card, SNDRV_DEV_CMD_NORMAL) < 0) {
		snd_printk(KERN_ERR "unable to free all devices (normal)\n");
		/* Fatal, but this situation should never occur */
	}
	if (snd_device_free_all(card, SNDRV_DEV_CMD_POST) < 0) {
		snd_printk(KERN_ERR "unable to free all devices (post)\n");
		/* Fatal, but this situation should never occur */
	}
	if (card->private_free)
		card->private_free(card);
	if (card->proc_id)
		snd_info_unregister(card->proc_id);
	if (snd_info_card_free(card) < 0) {
		snd_printk(KERN_WARNING "unable to free card info\n");
		/* Not fatal error */
	}
	snd_generic_device_unregister(card);
	while (card->s_f_ops) {
		s_f_ops = card->s_f_ops;
		card->s_f_ops = s_f_ops->next;
		kfree(s_f_ops);
	}
	write_lock(&snd_card_rwlock);
	snd_cards_lock &= ~(1 << card->number);
	write_unlock(&snd_card_rwlock);
	kfree(card);
	return 0;
}

static void snd_card_free_thread(void * __card)
{
	snd_card_t *card = __card;
	struct module * module = card->module;

	if (!try_module_get(module)) {
		snd_printk(KERN_ERR "unable to lock toplevel module for card %i in free thread\n", card->number);
		module = NULL;
	}

	snd_card_free(card);

	module_put(module);
}

/**
 *  snd_card_free_in_thread - call snd_card_free() in thread
 *  @card: soundcard structure
 *
 *  This function schedules the call of snd_card_free() function in a
 *  work queue.  When all devices are released (non-busy), the work
 *  is woken up and calls snd_card_free().
 *
 *  When a card can be disconnected at any time by hotplug service,
 *  this function should be used in disconnect (or detach) callback
 *  instead of calling snd_card_free() directly.
 *  
 *  Returns - zero otherwise a negative error code if the start of thread failed.
 */
int snd_card_free_in_thread(snd_card_t * card)
{
	if (card->files == NULL) {
		snd_card_free(card);
		return 0;
	}

	if (schedule_work(&card->free_workq))
		return 0;

	snd_printk(KERN_ERR "schedule_work() failed in snd_card_free_in_thread for card %i\n", card->number);
	/* try to free the structure immediately */
	snd_card_free(card);
	return -EFAULT;
}

static void choose_default_id(snd_card_t * card)
{
	int i, len, idx_flag = 0, loops = 8;
	char *id, *spos;
	
	id = spos = card->shortname;	
	while (*id != '\0') {
		if (*id == ' ')
			spos = id + 1;
		id++;
	}
	id = card->id;
	while (*spos != '\0' && !isalnum(*spos))
		spos++;
	if (isdigit(*spos))
		*id++ = isalpha(card->shortname[0]) ? card->shortname[0] : 'D';
	while (*spos != '\0' && (size_t)(id - card->id) < sizeof(card->id) - 1) {
		if (isalnum(*spos))
			*id++ = *spos;
		spos++;
	}
	*id = '\0';

	id = card->id;
	
	if (*id == '\0')
		strcpy(id, "default");

	while (1) {
	      	if (loops-- == 0) {
      			snd_printk(KERN_ERR "unable to choose default card id (%s)\n", id);
      			strcpy(card->id, card->proc_root->name);
      			return;
      		}
	      	if (!snd_info_check_reserved_words(id))
      			goto __change;
		for (i = 0; i < snd_ecards_limit; i++) {
			if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
				goto __change;
		}
		break;

	      __change:
		len = strlen(id);
		if (idx_flag)
			id[len-1]++;
		else if ((size_t)len <= sizeof(card->id) - 3) {
			strcat(id, "_1");
			idx_flag++;
		} else {
			spos = id + len - 2;
			if ((size_t)len <= sizeof(card->id) - 2)
				spos++;
			*spos++ = '_';
			*spos++ = '1';
			*spos++ = '\0';
			idx_flag++;
		}
	}
}

/**
 *  snd_card_register - register the soundcard
 *  @card: soundcard structure
 *
 *  This function registers all the devices assigned to the soundcard.
 *  Until calling this, the ALSA control interface is blocked from the
 *  external accesses.  Thus, you should call this function at the end
 *  of the initialization of the card.
 *
 *  Returns zero otherwise a negative error code if the registrain failed.
 */
int snd_card_register(snd_card_t * card)
{
	int err;
	snd_info_entry_t *entry;

	snd_runtime_check(card != NULL, return -EINVAL);
	if ((err = snd_device_register_all(card)) < 0)
		return err;
	write_lock(&snd_card_rwlock);
	if (snd_cards[card->number]) {
		/* already registered */
		write_unlock(&snd_card_rwlock);
		return 0;
	}
	if (card->id[0] == '\0')
		choose_default_id(card);
	snd_cards[card->number] = card;
	write_unlock(&snd_card_rwlock);
	if ((err = snd_info_card_register(card)) < 0) {
		snd_printd("unable to create card info\n");
		goto __skip_info;
	}
	if ((entry = snd_info_create_card_entry(card, "id", card->proc_root)) == NULL) {
		snd_printd("unable to create card entry\n");
		goto __skip_info;
	}
	entry->c.text.read_size = PAGE_SIZE;
	entry->c.text.read = snd_card_id_read;
	if (snd_info_register(entry) < 0) {
		snd_info_free_entry(entry);
		entry = NULL;
	}
	card->proc_id = entry;
      __skip_info:
#if defined(CONFIG_SND_MIXER_OSS) || defined(CONFIG_SND_MIXER_OSS_MODULE)
	if (snd_mixer_oss_notify_callback)
		snd_mixer_oss_notify_callback(card, SND_MIXER_OSS_NOTIFY_REGISTER);
#endif
	return 0;
}

static snd_info_entry_t *snd_card_info_entry = NULL;

static void snd_card_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
{
	int idx, count;
	snd_card_t *card;

	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
		read_lock(&snd_card_rwlock);
		if ((card = snd_cards[idx]) != NULL) {
			count++;
			snd_iprintf(buffer, "%i [%-15s]: %s - %s\n",
					idx,
					card->id,
					card->driver,
					card->shortname);
			snd_iprintf(buffer, "                     %s\n",
					card->longname);
		}
		read_unlock(&snd_card_rwlock);
	}
	if (!count)
		snd_iprintf(buffer, "--- no soundcards ---\n");
}

#if defined(CONFIG_SND_OSSEMUL) && defined(CONFIG_PROC_FS)

void snd_card_info_read_oss(snd_info_buffer_t * buffer)
{
	int idx, count;
	snd_card_t *card;

	for (idx = count = 0; idx < SNDRV_CARDS; idx++) {
		read_lock(&snd_card_rwlock);
		if ((card = snd_cards[idx]) != NULL) {
			count++;
			snd_iprintf(buffer, "%s\n", card->longname);
		}
		read_unlock(&snd_card_rwlock);
	}
	if (!count) {
		snd_iprintf(buffer, "--- no soundcards ---\n");
	}
}

#endif

#ifdef MODULE
static snd_info_entry_t *snd_card_module_info_entry;
static void snd_card_module_info_read(snd_info_entry_t *entry, snd_info_buffer_t * buffer)
{
	int idx;
	snd_card_t *card;

	for (idx = 0; idx < SNDRV_CARDS; idx++) {
		read_lock(&snd_card_rwlock);
		if ((card = snd_cards[idx]) != NULL)
			snd_iprintf(buffer, "%i %s\n", idx, card->module->name);
		read_unlock(&snd_card_rwlock);
	}
}
#endif

int __init snd_card_info_init(void)
{
	snd_info_entry_t *entry;

	entry = snd_info_create_module_entry(THIS_MODULE, "cards", NULL);
	snd_runtime_check(entry != NULL, return -ENOMEM);
	entry->c.text.read_size = PAGE_SIZE;
	entry->c.text.read = snd_card_info_read;
	if (snd_info_register(entry) < 0) {
		snd_info_free_entry(entry);
		return -ENOMEM;
	}
	snd_card_info_entry = entry;

#ifdef MODULE
	entry = snd_info_create_module_entry(THIS_MODULE, "modules", NULL);
	if (entry) {
		entry->c.text.read_size = PAGE_SIZE;
		entry->c.text.read = snd_card_module_info_read;
		if (snd_info_register(entry) < 0)
			snd_info_free_entry(entry);
		else
			snd_card_module_info_entry = entry;
	}
#endif

	return 0;
}

int __exit snd_card_info_done(void)
{
	if (snd_card_info_entry)
		snd_info_unregister(snd_card_info_entry);
#ifdef MODULE
	if (snd_card_module_info_entry)
		snd_info_unregister(snd_card_module_info_entry);
#endif
	return 0;
}

/**
 *  snd_component_add - add a component string
 *  @card: soundcard structure
 *  @component: the component id string
 *
 *  This function adds the component id string to the supported list.
 *  The component can be referred from the alsa-lib.
 *
 *  Returns zero otherwise a negative error code.
 */
  
int snd_component_add(snd_card_t *card, const char *component)
{
	char *ptr;
	int len = strlen(component);

	ptr = strstr(card->components, component);
	if (ptr != NULL) {
		if (ptr[len] == '\0' || ptr[len] == ' ')	/* already there */
			return 1;
	}
	if (strlen(card->components) + 1 + len + 1 > sizeof(card->components)) {
		snd_BUG();
		return -ENOMEM;
	}
	if (card->components[0] != '\0')
		strcat(card->components, " ");
	strcat(card->components, component);
	return 0;
}

/**
 *  snd_card_file_add - add the file to the file list of the card
 *  @card: soundcard structure
 *  @file: file pointer
 *
 *  This function adds the file to the file linked-list of the card.
 *  This linked-list is used to keep tracking the connection state,
 *  and to avoid the release of busy resources by hotplug.
 *
 *  Returns zero or a negative error code.
 */
int snd_card_file_add(snd_card_t *card, struct file *file)
{
	struct snd_monitor_file *mfile;

	mfile = kmalloc(sizeof(*mfile), GFP_KERNEL);
	if (mfile == NULL)
		return -ENOMEM;
	mfile->file = file;
	mfile->next = NULL;
	spin_lock(&card->files_lock);
	if (card->shutdown) {
		spin_unlock(&card->files_lock);
		kfree(mfile);
		return -ENODEV;
	}
	mfile->next = card->files;
	card->files = mfile;
	spin_unlock(&card->files_lock);
	return 0;
}

/**
 *  snd_card_file_remove - remove the file from the file list
 *  @card: soundcard structure
 *  @file: file pointer
 *
 *  This function removes the file formerly added to the card via
 *  snd_card_file_add() function.
 *  If all files are removed and the release of the card is
 *  scheduled, it will wake up the the thread to call snd_card_free()
 *  (see snd_card_free_in_thread() function).
 *
 *  Returns zero or a negative error code.
 */
int snd_card_file_remove(snd_card_t *card, struct file *file)
{
	struct snd_monitor_file *mfile, *pfile = NULL;

	spin_lock(&card->files_lock);
	mfile = card->files;
	while (mfile) {
		if (mfile->file == file) {
			if (pfile)
				pfile->next = mfile->next;
			else
				card->files = mfile->next;
			break;
		}
		pfile = mfile;
		mfile = mfile->next;
	}
	spin_unlock(&card->files_lock);
	if (card->files == NULL)
		wake_up(&card->shutdown_sleep);
	if (!mfile) {
		snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
		return -ENOENT;
	}
	kfree(mfile);
	return 0;
}

#ifdef CONFIG_SND_GENERIC_DRIVER
/*
 * generic device without a proper bus using platform_device
 * (e.g. ISA)
 */
struct snd_generic_device {
	struct platform_device pdev;
	snd_card_t *card;
};

#define get_snd_generic_card(dev)	container_of(to_platform_device(dev), struct snd_generic_device, pdev)->card

#define SND_GENERIC_NAME	"snd_generic"

#ifdef CONFIG_PM
static int snd_generic_suspend(struct device *dev, pm_message_t state);
static int snd_generic_resume(struct device *dev);
#endif

/* initialized in sound.c */
struct device_driver snd_generic_driver = {
	.name		= SND_GENERIC_NAME,
	.bus		= &platform_bus_type,
#ifdef CONFIG_PM
	.suspend	= snd_generic_suspend,
	.resume		= snd_generic_resume,
#endif
};

void snd_generic_device_release(struct device *dev)
{
}

static int snd_generic_device_register(snd_card_t *card)
{
	struct snd_generic_device *dev;
	int err;

	if (card->generic_dev)
		return 0; /* already registered */

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (! dev) {
		snd_printk(KERN_ERR "can't allocate generic_device\n");
		return -ENOMEM;
	}

	dev->pdev.name = SND_GENERIC_NAME;
	dev->pdev.id = card->number;
	dev->pdev.dev.release = snd_generic_device_release;
	dev->card = card;
	if ((err = platform_device_register(&dev->pdev)) < 0) {
		kfree(dev);
		return err;
	}
	card->generic_dev = dev;
	return 0;
}

static void snd_generic_device_unregister(snd_card_t *card)
{
	struct snd_generic_device *dev = card->generic_dev;
	if (dev) {
		platform_device_unregister(&dev->pdev);
		kfree(dev);
		card->generic_dev = NULL;
	}
}

/**
 * snd_card_set_generic_dev - assign the generic device to the card
 * @card: soundcard structure
 *
 * Assigns a generic device to the card.  This function is provided as the
 * last resort, for devices without any proper bus.  Thus this won't override
 * the device already assigned to the card.
 * 
 * Returns zero if successful, or a negative error code.
 */
int snd_card_set_generic_dev(snd_card_t *card)
{
	int err;
	if ((err = snd_generic_device_register(card)) < 0)
		return err;
	if (! card->dev)
		snd_card_set_dev(card, &card->generic_dev->pdev.dev);
	return 0;
}
#endif /* CONFIG_SND_GENERIC_DRIVER */

#ifdef CONFIG_PM
/**
 *  snd_power_wait - wait until the power-state is changed.
 *  @card: soundcard structure
 *  @power_state: expected power state
 *  @file: file structure for the O_NONBLOCK check (optional)
 *
 *  Waits until the power-state is changed.
 *
 *  Note: the power lock must be active before call.
 */
int snd_power_wait(snd_card_t *card, unsigned int power_state, struct file *file)
{
	wait_queue_t wait;
	int result = 0;

	/* fastpath */
	if (snd_power_get_state(card) == power_state)
		return 0;
	init_waitqueue_entry(&wait, current);
	add_wait_queue(&card->power_sleep, &wait);
	while (1) {
		if (card->shutdown) {
			result = -ENODEV;
			break;
		}
		if (snd_power_get_state(card) == power_state)
			break;
#if 0 /* block all devices */
		if (file && (file->f_flags & O_NONBLOCK)) {
			result = -EAGAIN;
			break;
		}
#endif
		set_current_state(TASK_UNINTERRUPTIBLE);
		snd_power_unlock(card);
		schedule_timeout(30 * HZ);
		snd_power_lock(card);
	}
	remove_wait_queue(&card->power_sleep, &wait);
	return result;
}

/**
 * snd_card_set_pm_callback - set the PCI power-management callbacks
 * @card: soundcard structure
 * @suspend: suspend callback function
 * @resume: resume callback function
 * @private_data: private data to pass to the callback functions
 *
 * Sets the power-management callback functions of the card.
 * These callbacks are called from ALSA's common PCI suspend/resume
 * handler and from the control API.
 */
int snd_card_set_pm_callback(snd_card_t *card,
			     int (*suspend)(snd_card_t *, pm_message_t),
			     int (*resume)(snd_card_t *),
			     void *private_data)
{
	card->pm_suspend = suspend;
	card->pm_resume = resume;
	card->pm_private_data = private_data;
	return 0;
}

#ifdef CONFIG_SND_GENERIC_DRIVER
/* suspend/resume callbacks for snd_generic platform device */