⭐ 欢迎来到虫虫下载站! | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站

📄 seq_oss_init.c

📁 linux-2.6.15.6
💻 C
字号:
/* * OSS compatible sequencer driver * * open/close and reset interface * * Copyright (C) 1998-1999 Takashi Iwai <tiwai@suse.de> * * 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 "seq_oss_device.h"#include "seq_oss_synth.h"#include "seq_oss_midi.h"#include "seq_oss_writeq.h"#include "seq_oss_readq.h"#include "seq_oss_timer.h"#include "seq_oss_event.h"#include <linux/init.h>#include <linux/moduleparam.h>/* * common variables */static int maxqlen = SNDRV_SEQ_OSS_MAX_QLEN;module_param(maxqlen, int, 0444);MODULE_PARM_DESC(maxqlen, "maximum queue length");static int system_client = -1; /* ALSA sequencer client number */static int system_port = -1;static int num_clients;static seq_oss_devinfo_t *client_table[SNDRV_SEQ_OSS_MAX_CLIENTS];/* * prototypes */static int receive_announce(snd_seq_event_t *ev, int direct, void *private, int atomic, int hop);static int translate_mode(struct file *file);static int create_port(seq_oss_devinfo_t *dp);static int delete_port(seq_oss_devinfo_t *dp);static int alloc_seq_queue(seq_oss_devinfo_t *dp);static int delete_seq_queue(int queue);static void free_devinfo(void *private);#define call_ctl(type,rec) snd_seq_kernel_client_ctl(system_client, type, rec)/* * create sequencer client for OSS sequencer */int __initsnd_seq_oss_create_client(void){	int rc;	snd_seq_client_callback_t callback;	snd_seq_client_info_t *info;	snd_seq_port_info_t *port;	snd_seq_port_callback_t port_callback;	info = kmalloc(sizeof(*info), GFP_KERNEL);	port = kmalloc(sizeof(*port), GFP_KERNEL);	if (!info || !port) {		rc = -ENOMEM;		goto __error;	}	/* create ALSA client */	memset(&callback, 0, sizeof(callback));	callback.private_data = NULL;	callback.allow_input = 1;	callback.allow_output = 1;	rc = snd_seq_create_kernel_client(NULL, SNDRV_SEQ_CLIENT_OSS, &callback);	if (rc < 0)		goto __error;	system_client = rc;	debug_printk(("new client = %d\n", rc));	/* set client information */	memset(info, 0, sizeof(*info));	info->client = system_client;	info->type = KERNEL_CLIENT;	strcpy(info->name, "OSS sequencer");	rc = call_ctl(SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, info);	/* look up midi devices */	snd_seq_oss_midi_lookup_ports(system_client);	/* create annoucement receiver port */	memset(port, 0, sizeof(*port));	strcpy(port->name, "Receiver");	port->addr.client = system_client;	port->capability = SNDRV_SEQ_PORT_CAP_WRITE; /* receive only */	port->type = 0;	memset(&port_callback, 0, sizeof(port_callback));	/* don't set port_callback.owner here. otherwise the module counter	 * is incremented and we can no longer release the module..	 */	port_callback.event_input = receive_announce;	port->kernel = &port_callback;		call_ctl(SNDRV_SEQ_IOCTL_CREATE_PORT, port);	if ((system_port = port->addr.port) >= 0) {		snd_seq_port_subscribe_t subs;		memset(&subs, 0, sizeof(subs));		subs.sender.client = SNDRV_SEQ_CLIENT_SYSTEM;		subs.sender.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;		subs.dest.client = system_client;		subs.dest.port = system_port;		call_ctl(SNDRV_SEQ_IOCTL_SUBSCRIBE_PORT, &subs);	}	rc = 0; __error:	kfree(port);	kfree(info);	return rc;}/* * receive annoucement from system port, and check the midi device */static intreceive_announce(snd_seq_event_t *ev, int direct, void *private, int atomic, int hop){	snd_seq_port_info_t pinfo;	if (atomic)		return 0; /* it must not happen */	switch (ev->type) {	case SNDRV_SEQ_EVENT_PORT_START:	case SNDRV_SEQ_EVENT_PORT_CHANGE:		if (ev->data.addr.client == system_client)			break; /* ignore myself */		memset(&pinfo, 0, sizeof(pinfo));		pinfo.addr = ev->data.addr;		if (call_ctl(SNDRV_SEQ_IOCTL_GET_PORT_INFO, &pinfo) >= 0)			snd_seq_oss_midi_check_new_port(&pinfo);		break;	case SNDRV_SEQ_EVENT_PORT_EXIT:		if (ev->data.addr.client == system_client)			break; /* ignore myself */		snd_seq_oss_midi_check_exit_port(ev->data.addr.client,						ev->data.addr.port);		break;	}	return 0;}/* * delete OSS sequencer client */intsnd_seq_oss_delete_client(void){	if (system_client >= 0)		snd_seq_delete_kernel_client(system_client);	snd_seq_oss_midi_clear_all();	return 0;}/* * open sequencer device */intsnd_seq_oss_open(struct file *file, int level){	int i, rc;	seq_oss_devinfo_t *dp;	if ((dp = kzalloc(sizeof(*dp), GFP_KERNEL)) == NULL) {		snd_printk(KERN_ERR "can't malloc device info\n");		return -ENOMEM;	}	debug_printk(("oss_open: dp = %p\n", dp));	for (i = 0; i < SNDRV_SEQ_OSS_MAX_CLIENTS; i++) {		if (client_table[i] == NULL)			break;	}	if (i >= SNDRV_SEQ_OSS_MAX_CLIENTS) {		snd_printk(KERN_ERR "too many applications\n");		kfree(dp);		return -ENOMEM;	}	dp->index = i;	dp->cseq = system_client;	dp->port = -1;	dp->queue = -1;	dp->readq = NULL;	dp->writeq = NULL;	/* look up synth and midi devices */	snd_seq_oss_synth_setup(dp);	snd_seq_oss_midi_setup(dp);	if (dp->synth_opened == 0 && dp->max_mididev == 0) {		/* snd_printk(KERN_ERR "no device found\n"); */		rc = -ENODEV;		goto _error;	}	/* create port */	debug_printk(("create new port\n"));	if ((rc = create_port(dp)) < 0) {		snd_printk(KERN_ERR "can't create port\n");		goto _error;	}	/* allocate queue */	debug_printk(("allocate queue\n"));	if ((rc = alloc_seq_queue(dp)) < 0)		goto _error;	/* set address */	dp->addr.client = dp->cseq;	dp->addr.port = dp->port;	/*dp->addr.queue = dp->queue;*/	/*dp->addr.channel = 0;*/	dp->seq_mode = level;	/* set up file mode */	dp->file_mode = translate_mode(file);	/* initialize read queue */	debug_printk(("initialize read queue\n"));	if (is_read_mode(dp->file_mode)) {		if ((dp->readq = snd_seq_oss_readq_new(dp, maxqlen)) == NULL) {			rc = -ENOMEM;			goto _error;		}	}	/* initialize write queue */	debug_printk(("initialize write queue\n"));	if (is_write_mode(dp->file_mode)) {		dp->writeq = snd_seq_oss_writeq_new(dp, maxqlen);		if (dp->writeq == NULL) {			rc = -ENOMEM;			goto _error;		}	}	/* initialize timer */	debug_printk(("initialize timer\n"));	if ((dp->timer = snd_seq_oss_timer_new(dp)) == NULL) {		snd_printk(KERN_ERR "can't alloc timer\n");		rc = -ENOMEM;		goto _error;	}	debug_printk(("timer initialized\n"));	/* set private data pointer */	file->private_data = dp;	/* set up for mode2 */	if (level == SNDRV_SEQ_OSS_MODE_MUSIC)		snd_seq_oss_synth_setup_midi(dp);	else if (is_read_mode(dp->file_mode))		snd_seq_oss_midi_open_all(dp, SNDRV_SEQ_OSS_FILE_READ);	client_table[dp->index] = dp;	num_clients++;	debug_printk(("open done\n"));	return 0; _error:	snd_seq_oss_synth_cleanup(dp);	snd_seq_oss_midi_cleanup(dp);	i = dp->queue;	delete_port(dp);	delete_seq_queue(i);	return rc;}/* * translate file flags to private mode */static inttranslate_mode(struct file *file){	int file_mode = 0;	if ((file->f_flags & O_ACCMODE) != O_RDONLY)		file_mode |= SNDRV_SEQ_OSS_FILE_WRITE;	if ((file->f_flags & O_ACCMODE) != O_WRONLY)		file_mode |= SNDRV_SEQ_OSS_FILE_READ;	if (file->f_flags & O_NONBLOCK)		file_mode |= SNDRV_SEQ_OSS_FILE_NONBLOCK;	return file_mode;}/* * create sequencer port */static intcreate_port(seq_oss_devinfo_t *dp){	int rc;	snd_seq_port_info_t port;	snd_seq_port_callback_t callback;	memset(&port, 0, sizeof(port));	port.addr.client = dp->cseq;	sprintf(port.name, "Sequencer-%d", dp->index);	port.capability = SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_WRITE; /* no subscription */	port.type = SNDRV_SEQ_PORT_TYPE_SPECIFIC;	port.midi_channels = 128;	port.synth_voices = 128;	memset(&callback, 0, sizeof(callback));	callback.owner = THIS_MODULE;	callback.private_data = dp;	callback.event_input = snd_seq_oss_event_input;	callback.private_free = free_devinfo;	port.kernel = &callback;	rc = call_ctl(SNDRV_SEQ_IOCTL_CREATE_PORT, &port);	if (rc < 0)		return rc;	dp->port = port.addr.port;	debug_printk(("new port = %d\n", port.addr.port));	return 0;}/* * delete ALSA port */static intdelete_port(seq_oss_devinfo_t *dp){	if (dp->port < 0)		return 0;	debug_printk(("delete_port %i\n", dp->port));	return snd_seq_event_port_detach(dp->cseq, dp->port);}/* * allocate a queue */static intalloc_seq_queue(seq_oss_devinfo_t *dp){	snd_seq_queue_info_t qinfo;	int rc;	memset(&qinfo, 0, sizeof(qinfo));	qinfo.owner = system_client;	qinfo.locked = 1;	strcpy(qinfo.name, "OSS Sequencer Emulation");	if ((rc = call_ctl(SNDRV_SEQ_IOCTL_CREATE_QUEUE, &qinfo)) < 0)		return rc;	dp->queue = qinfo.queue;	return 0;}/* * release queue */static intdelete_seq_queue(int queue){	snd_seq_queue_info_t qinfo;	int rc;	if (queue < 0)		return 0;	memset(&qinfo, 0, sizeof(qinfo));	qinfo.queue = queue;	rc = call_ctl(SNDRV_SEQ_IOCTL_DELETE_QUEUE, &qinfo);	if (rc < 0)		printk(KERN_ERR "seq-oss: unable to delete queue %d (%d)\n", queue, rc);	return rc;}/* * free device informations - private_free callback of port */static voidfree_devinfo(void *private){	seq_oss_devinfo_t *dp = (seq_oss_devinfo_t *)private;	if (dp->timer)		snd_seq_oss_timer_delete(dp->timer);			if (dp->writeq)		snd_seq_oss_writeq_delete(dp->writeq);	if (dp->readq)		snd_seq_oss_readq_delete(dp->readq);		kfree(dp);}/* * close sequencer device */voidsnd_seq_oss_release(seq_oss_devinfo_t *dp){	int queue;	client_table[dp->index] = NULL;	num_clients--;	debug_printk(("resetting..\n"));	snd_seq_oss_reset(dp);	debug_printk(("cleaning up..\n"));	snd_seq_oss_synth_cleanup(dp);	snd_seq_oss_midi_cleanup(dp);	/* clear slot */	debug_printk(("releasing resource..\n"));	queue = dp->queue;	if (dp->port >= 0)		delete_port(dp);	delete_seq_queue(queue);	debug_printk(("release done\n"));}/* * Wait until the queue is empty (if we don't have nonblock) */voidsnd_seq_oss_drain_write(seq_oss_devinfo_t *dp){	if (! dp->timer->running)		return;	if (is_write_mode(dp->file_mode) && !is_nonblock_mode(dp->file_mode) &&	    dp->writeq) {		debug_printk(("syncing..\n"));		while (snd_seq_oss_writeq_sync(dp->writeq))			;	}}/* * reset sequencer devices */voidsnd_seq_oss_reset(seq_oss_devinfo_t *dp){	int i;	/* reset all synth devices */	for (i = 0; i < dp->max_synthdev; i++)		snd_seq_oss_synth_reset(dp, i);	/* reset all midi devices */	if (dp->seq_mode != SNDRV_SEQ_OSS_MODE_MUSIC) {		for (i = 0; i < dp->max_mididev; i++)			snd_seq_oss_midi_reset(dp, i);	}	/* remove queues */	if (dp->readq)		snd_seq_oss_readq_clear(dp->readq);	if (dp->writeq)		snd_seq_oss_writeq_clear(dp->writeq);	/* reset timer */	snd_seq_oss_timer_stop(dp->timer);}/* * misc. functions for proc interface */char *enabled_str(int bool){	return bool ? "enabled" : "disabled";}static char *filemode_str(int val){	static char *str[] = {		"none", "read", "write", "read/write",	};	return str[val & SNDRV_SEQ_OSS_FILE_ACMODE];}/* * proc interface */voidsnd_seq_oss_system_info_read(snd_info_buffer_t *buf){	int i;	seq_oss_devinfo_t *dp;	snd_iprintf(buf, "ALSA client number %d\n", system_client);	snd_iprintf(buf, "ALSA receiver port %d\n", system_port);	snd_iprintf(buf, "\nNumber of applications: %d\n", num_clients);	for (i = 0; i < num_clients; i++) {		snd_iprintf(buf, "\nApplication %d: ", i);		if ((dp = client_table[i]) == NULL) {			snd_iprintf(buf, "*empty*\n");			continue;		}		snd_iprintf(buf, "port %d : queue %d\n", dp->port, dp->queue);		snd_iprintf(buf, "  sequencer mode = %s : file open mode = %s\n",			    (dp->seq_mode ? "music" : "synth"),			    filemode_str(dp->file_mode));		if (dp->seq_mode)			snd_iprintf(buf, "  timer tempo = %d, timebase = %d\n",				    dp->timer->oss_tempo, dp->timer->oss_timebase);		snd_iprintf(buf, "  max queue length %d\n", maxqlen);		if (is_read_mode(dp->file_mode) && dp->readq)			snd_seq_oss_readq_info_read(dp->readq, buf);	}}

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -