⭐ 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

📄 tvmixer.c

📁 linux-2.6.15.6
💻 C
字号:
/* */#include <linux/module.h>#include <linux/moduleparam.h>#include <linux/kernel.h>#include <linux/sched.h>#include <linux/string.h>#include <linux/timer.h>#include <linux/delay.h>#include <linux/errno.h>#include <linux/slab.h>#include <linux/i2c.h>#include <linux/videodev.h>#include <linux/init.h>#include <linux/kdev_t.h>#include <linux/sound.h>#include <linux/soundcard.h>#include <asm/semaphore.h>#include <asm/uaccess.h>#define DEV_MAX  4static int devnr = -1;module_param(devnr, int, 0644);MODULE_AUTHOR("Gerd Knorr");MODULE_LICENSE("GPL");/* ----------------------------------------------------------------------- */struct TVMIXER {	struct i2c_client *dev;	int minor;	int count;};static struct TVMIXER devices[DEV_MAX];static int tvmixer_adapters(struct i2c_adapter *adap);static int tvmixer_clients(struct i2c_client *client);/* ----------------------------------------------------------------------- */static int mix_to_v4l(int i){	int r;	r = ((i & 0xff) * 65536 + 50) / 100;	if (r > 65535) r = 65535;	if (r <     0) r =     0;	return r;}static int v4l_to_mix(int i){	int r;	r = (i * 100 + 32768) / 65536;	if (r > 100) r = 100;	if (r <   0) r =   0;	return r | (r << 8);}static int v4l_to_mix2(int l, int r){	r = (r * 100 + 32768) / 65536;	if (r > 100) r = 100;	if (r <   0) r =   0;	l = (l * 100 + 32768) / 65536;	if (l > 100) l = 100;	if (l <   0) l =   0;	return (r << 8) | l;}static int tvmixer_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg){	struct video_audio va;	int left,right,ret,val = 0;	struct TVMIXER *mix = file->private_data;	struct i2c_client *client = mix->dev;	void __user *argp = (void __user *)arg;	int __user *p = argp;	if (NULL == client)		return -ENODEV;	if (cmd == SOUND_MIXER_INFO) {		mixer_info info;		strlcpy(info.id, "tv card", sizeof(info.id));		strlcpy(info.name, client->name, sizeof(info.name));		info.modify_counter = 42 /* FIXME */;		if (copy_to_user(argp, &info, sizeof(info)))			return -EFAULT;		return 0;	}	if (cmd == SOUND_OLD_MIXER_INFO) {		_old_mixer_info info;		strlcpy(info.id, "tv card", sizeof(info.id));		strlcpy(info.name, client->name, sizeof(info.name));		if (copy_to_user(argp, &info, sizeof(info)))			return -EFAULT;		return 0;	}	if (cmd == OSS_GETVERSION)		return put_user(SOUND_VERSION, p);	if (_SIOC_DIR(cmd) & _SIOC_WRITE)		if (get_user(val, p))			return -EFAULT;	/* read state */	memset(&va,0,sizeof(va));	client->driver->command(client,VIDIOCGAUDIO,&va);	switch (cmd) {	case MIXER_READ(SOUND_MIXER_RECMASK):	case MIXER_READ(SOUND_MIXER_CAPS):	case MIXER_READ(SOUND_MIXER_RECSRC):	case MIXER_WRITE(SOUND_MIXER_RECSRC):		ret = 0;		break;	case MIXER_READ(SOUND_MIXER_STEREODEVS):		ret = SOUND_MASK_VOLUME;		break;	case MIXER_READ(SOUND_MIXER_DEVMASK):		ret = SOUND_MASK_VOLUME;		if (va.flags & VIDEO_AUDIO_BASS)			ret |= SOUND_MASK_BASS;		if (va.flags & VIDEO_AUDIO_TREBLE)			ret |= SOUND_MASK_TREBLE;		break;	case MIXER_WRITE(SOUND_MIXER_VOLUME):		left  = mix_to_v4l(val);		right = mix_to_v4l(val >> 8);		va.volume  = max(left,right);		va.balance = (32768*min(left,right)) / (va.volume ? va.volume : 1);		va.balance = (left<right) ? (65535-va.balance) : va.balance;		if (va.volume)			va.flags &= ~VIDEO_AUDIO_MUTE;		client->driver->command(client,VIDIOCSAUDIO,&va);		client->driver->command(client,VIDIOCGAUDIO,&va);		/* fall throuth */	case MIXER_READ(SOUND_MIXER_VOLUME):		left  = (min(65536 - va.balance,32768) *			 va.volume) / 32768;		right = (min(va.balance,(u16)32768) *			 va.volume) / 32768;		ret = v4l_to_mix2(left,right);		break;	case MIXER_WRITE(SOUND_MIXER_BASS):		va.bass = mix_to_v4l(val);		client->driver->command(client,VIDIOCSAUDIO,&va);		client->driver->command(client,VIDIOCGAUDIO,&va);		/* fall throuth  */	case MIXER_READ(SOUND_MIXER_BASS):		ret = v4l_to_mix(va.bass);		break;	case MIXER_WRITE(SOUND_MIXER_TREBLE):		va.treble = mix_to_v4l(val);		client->driver->command(client,VIDIOCSAUDIO,&va);		client->driver->command(client,VIDIOCGAUDIO,&va);		/* fall throuth */	case MIXER_READ(SOUND_MIXER_TREBLE):		ret = v4l_to_mix(va.treble);		break;	default:		return -EINVAL;	}	if (put_user(ret, p))		return -EFAULT;	return 0;}static int tvmixer_open(struct inode *inode, struct file *file){	int i, minor = iminor(inode);	struct TVMIXER *mix = NULL;	struct i2c_client *client = NULL;	for (i = 0; i < DEV_MAX; i++) {		if (devices[i].minor == minor) {			mix = devices+i;			client = mix->dev;			break;		}	}	if (NULL == client)		return -ENODEV;	/* lock bttv in memory while the mixer is in use  */	file->private_data = mix;#ifndef I2C_PEC	if (client->adapter->inc_use)		client->adapter->inc_use(client->adapter);#endif	if (client->adapter->owner)		try_module_get(client->adapter->owner);	return 0;}static int tvmixer_release(struct inode *inode, struct file *file){	struct TVMIXER *mix = file->private_data;	struct i2c_client *client;	client = mix->dev;	if (NULL == client) {		return -ENODEV;	}#ifndef I2C_PEC	if (client->adapter->dec_use)		client->adapter->dec_use(client->adapter);#endif	if (client->adapter->owner)		module_put(client->adapter->owner);	return 0;}static struct i2c_driver driver = {#ifdef I2C_PEC	.owner           = THIS_MODULE,#endif	.name            = "tv card mixer driver",	.id              = I2C_DRIVERID_TVMIXER,#ifdef I2C_DF_DUMMY	.flags           = I2C_DF_DUMMY,#else	.flags           = I2C_DF_NOTIFY,	.detach_adapter  = tvmixer_adapters,#endif	.attach_adapter  = tvmixer_adapters,	.detach_client   = tvmixer_clients,};static struct file_operations tvmixer_fops = {	.owner		= THIS_MODULE,	.llseek         = no_llseek,	.ioctl          = tvmixer_ioctl,	.open           = tvmixer_open,	.release        = tvmixer_release,};/* ----------------------------------------------------------------------- */static int tvmixer_adapters(struct i2c_adapter *adap){	struct list_head  *item;	struct i2c_client *client;	list_for_each(item,&adap->clients) {		client = list_entry(item, struct i2c_client, list);		tvmixer_clients(client);	}	return 0;}static int tvmixer_clients(struct i2c_client *client){	struct video_audio va;	int i,minor;#ifdef I2C_CLASS_TV_ANALOG	if (!(client->adapter->class & I2C_CLASS_TV_ANALOG))		return -1;#else	/* TV card ??? */	switch (client->adapter->id) {	case I2C_HW_SMBUS_VOODOO3:	case I2C_HW_B_BT848:	case I2C_HW_B_RIVA:		/* ok, have a look ... */		break;	default:		/* ignore that one */		return -1;	}#endif	/* unregister ?? */	for (i = 0; i < DEV_MAX; i++) {		if (devices[i].dev == client) {			/* unregister */			unregister_sound_mixer(devices[i].minor);			devices[i].dev = NULL;			devices[i].minor = -1;			printk("tvmixer: %s unregistered (#1)\n",			       client->name);			return 0;		}	}	/* look for a free slot */	for (i = 0; i < DEV_MAX; i++)		if (NULL == devices[i].dev)			break;	if (i == DEV_MAX) {		printk(KERN_WARNING "tvmixer: DEV_MAX too small\n");		return -1;	}	/* audio chip with mixer ??? */	if (NULL == client->driver->command)		return -1;	memset(&va,0,sizeof(va));	if (0 != client->driver->command(client,VIDIOCGAUDIO,&va))		return -1;	if (0 == (va.flags & VIDEO_AUDIO_VOLUME))		return -1;	/* everything is fine, register */	if ((minor = register_sound_mixer(&tvmixer_fops,devnr)) < 0) {		printk(KERN_ERR "tvmixer: cannot allocate mixer device\n");		return -1;	}	devices[i].minor = minor;	devices[i].count = 0;	devices[i].dev   = client;	printk("tvmixer: %s (%s) registered with minor %d\n",	       client->name,client->adapter->name,minor);	return 0;}/* ----------------------------------------------------------------------- */static int __init tvmixer_init_module(void){	int i;	for (i = 0; i < DEV_MAX; i++)		devices[i].minor = -1;	return i2c_add_driver(&driver);}static void __exit tvmixer_cleanup_module(void){	int i;	i2c_del_driver(&driver);	for (i = 0; i < DEV_MAX; i++) {		if (devices[i].minor != -1) {			unregister_sound_mixer(devices[i].minor);			printk("tvmixer: %s unregistered (#2)\n",			       devices[i].dev->name);		}	}}module_init(tvmixer_init_module);module_exit(tvmixer_cleanup_module);/* * Overrides for Emacs so that we follow Linus's tabbing style. * --------------------------------------------------------------------------- * Local variables: * c-basic-offset: 8 * End: */

⌨️ 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 + -