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root/sound/oss/soundcard.c

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DEFINITIONS

This source file includes following definitions.
  1. load_mixer_volumes
  2. set_mixer_levels
  3. get_mixer_levels
  4. sound_read
  5. sound_write
  6. sound_open
  7. sound_release
  8. get_mixer_info
  9. get_old_mixer_info
  10. sound_mixer_ioctl
  11. sound_ioctl
  12. sound_poll
  13. sound_mmap
  14. create_special_devices
  15. oss_init
  16. oss_cleanup
  17. sound_alloc_dma
  18. sound_open_dma
  19. sound_free_dma
  20. sound_close_dma
  21. do_sequencer_timer
  22. request_sound_timer
  23. sound_stop_timer
  24. conf_printf
  25. conf_printf2

/*
 * linux/sound/oss/soundcard.c
 *
 * Sound card driver for Linux
 *
 *
 * Copyright (C) by Hannu Savolainen 1993-1997
 *
 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
 * Version 2 (June 1991). See the "COPYING" file distributed with this software
 * for more info.
 *
 *
 * Thomas Sailer     : ioctl code reworked (vmalloc/vfree removed)
 *                   integrated sound_switch.c
 * Stefan Reinauer   : integrated /proc/sound (equals to /dev/sndstat,
 *                   which should disappear in the near future)
 * Eric Dumas        : devfs support (22-Jan-98) <dumas@linux.eu.org> with
 *                   fixups by C. Scott Ananian <cananian@alumni.princeton.edu>
 * Richard Gooch     : moved common (non OSS-specific) devices to sound_core.c
 * Rob Riggs         : Added persistent DMA buffers support (1998/10/17)
 * Christoph Hellwig : Some cleanup work (2000/03/01)
 */


#include "sound_config.h"
#include <linux/init.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/fcntl.h>
#include <linux/ctype.h>
#include <linux/stddef.h>
#include <linux/kmod.h>
#include <linux/kernel.h>
#include <asm/dma.h>
#include <asm/io.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/major.h>
#include <linux/delay.h>
#include <linux/proc_fs.h>
#include <linux/smp_lock.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/device.h>

/*
 * This ought to be moved into include/asm/dma.h
 */
#ifndef valid_dma
#define valid_dma(n) ((n) >= 0 && (n) < MAX_DMA_CHANNELS && (n) != 4)
#endif

/*
 * Table for permanently allocated memory (used when unloading the module)
 */
void *          sound_mem_blocks[1024];
int             sound_nblocks = 0;

/* Persistent DMA buffers */
#ifdef CONFIG_SOUND_DMAP
int             sound_dmap_flag = 1;
#else
int             sound_dmap_flag = 0;
#endif

static char     dma_alloc_map[MAX_DMA_CHANNELS];

#define DMA_MAP_UNAVAIL         0
#define DMA_MAP_FREE            1
#define DMA_MAP_BUSY            2


unsigned long seq_time = 0;     /* Time for /dev/sequencer */
extern struct class *sound_class;

/*
 * Table for configurable mixer volume handling
 */
static mixer_vol_table mixer_vols[MAX_MIXER_DEV];
static int num_mixer_volumes;

int *load_mixer_volumes(char *name, int *levels, int present)
{
        int             i, n;

        for (i = 0; i < num_mixer_volumes; i++) {
                if (strcmp(name, mixer_vols[i].name) == 0) {
                        if (present)
                                mixer_vols[i].num = i;
                        return mixer_vols[i].levels;
                }
        }
        if (num_mixer_volumes >= MAX_MIXER_DEV) {
                printk(KERN_ERR "Sound: Too many mixers (%s)\n", name);
                return levels;
        }
        n = num_mixer_volumes++;

        strcpy(mixer_vols[n].name, name);

        if (present)
                mixer_vols[n].num = n;
        else
                mixer_vols[n].num = -1;

        for (i = 0; i < 32; i++)
                mixer_vols[n].levels[i] = levels[i];
        return mixer_vols[n].levels;
}
EXPORT_SYMBOL(load_mixer_volumes);

static int set_mixer_levels(void __user * arg)
{
        /* mixer_vol_table is 174 bytes, so IMHO no reason to not allocate it on the stack */
        mixer_vol_table buf;   

        if (__copy_from_user(&buf, arg, sizeof(buf)))
                return -EFAULT;
        load_mixer_volumes(buf.name, buf.levels, 0);
        if (__copy_to_user(arg, &buf, sizeof(buf)))
                return -EFAULT;
        return 0;
}

static int get_mixer_levels(void __user * arg)
{
        int n;

        if (__get_user(n, (int __user *)(&(((mixer_vol_table __user *)arg)->num))))
                return -EFAULT;
        if (n < 0 || n >= num_mixer_volumes)
                return -EINVAL;
        if (__copy_to_user(arg, &mixer_vols[n], sizeof(mixer_vol_table)))
                return -EFAULT;
        return 0;
}

/* 4K page size but our output routines use some slack for overruns */
#define PROC_BLOCK_SIZE (3*1024)

static ssize_t sound_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
{
        int dev = iminor(file->f_path.dentry->d_inode);
        int ret = -EINVAL;

        /*
         *      The OSS drivers aren't remotely happy without this locking,
         *      and unless someone fixes them when they are about to bite the
         *      big one anyway, we might as well bandage here..
         */
         
        lock_kernel();
        
        DEB(printk("sound_read(dev=%d, count=%d)\n", dev, count));
        switch (dev & 0x0f) {
        case SND_DEV_DSP:
        case SND_DEV_DSP16:
        case SND_DEV_AUDIO:
                ret = audio_read(dev, file, buf, count);
                break;

        case SND_DEV_SEQ:
        case SND_DEV_SEQ2:
                ret = sequencer_read(dev, file, buf, count);
                break;

        case SND_DEV_MIDIN:
                ret = MIDIbuf_read(dev, file, buf, count);
        }
        unlock_kernel();
        return ret;
}

static ssize_t sound_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
        int dev = iminor(file->f_path.dentry->d_inode);
        int ret = -EINVAL;
        
        lock_kernel();
        DEB(printk("sound_write(dev=%d, count=%d)\n", dev, count));
        switch (dev & 0x0f) {
        case SND_DEV_SEQ:
        case SND_DEV_SEQ2:
                ret =  sequencer_write(dev, file, buf, count);
                break;

        case SND_DEV_DSP:
        case SND_DEV_DSP16:
        case SND_DEV_AUDIO:
                ret = audio_write(dev, file, buf, count);
                break;

        case SND_DEV_MIDIN:
                ret =  MIDIbuf_write(dev, file, buf, count);
                break;
        }
        unlock_kernel();
        return ret;
}

static int sound_open(struct inode *inode, struct file *file)
{
        int dev = iminor(inode);
        int retval;

        DEB(printk("sound_open(dev=%d)\n", dev));
        if ((dev >= SND_NDEVS) || (dev < 0)) {
                printk(KERN_ERR "Invalid minor device %d\n", dev);
                return -ENXIO;
        }
        switch (dev & 0x0f) {
        case SND_DEV_CTL:
                dev >>= 4;
                if (dev >= 0 && dev < MAX_MIXER_DEV && mixer_devs[dev] == NULL) {
                        request_module("mixer%d", dev);
                }
                if (dev && (dev >= num_mixers || mixer_devs[dev] == NULL))
                        return -ENXIO;
        
                if (!try_module_get(mixer_devs[dev]->owner))
                        return -ENXIO;
                break;

        case SND_DEV_SEQ:
        case SND_DEV_SEQ2:
                if ((retval = sequencer_open(dev, file)) < 0)
                        return retval;
                break;

        case SND_DEV_MIDIN:
                if ((retval = MIDIbuf_open(dev, file)) < 0)
                        return retval;
                break;

        case SND_DEV_DSP:
        case SND_DEV_DSP16:
        case SND_DEV_AUDIO:
                if ((retval = audio_open(dev, file)) < 0)
                        return retval;
                break;

        default:
                printk(KERN_ERR "Invalid minor device %d\n", dev);
                return -ENXIO;
        }

        return 0;
}

static int sound_release(struct inode *inode, struct file *file)
{
        int dev = iminor(inode);

        lock_kernel();
        DEB(printk("sound_release(dev=%d)\n", dev));
        switch (dev & 0x0f) {
        case SND_DEV_CTL:
                module_put(mixer_devs[dev >> 4]->owner);
                break;
                
        case SND_DEV_SEQ:
        case SND_DEV_SEQ2:
                sequencer_release(dev, file);
                break;

        case SND_DEV_MIDIN:
                MIDIbuf_release(dev, file);
                break;

        case SND_DEV_DSP:
        case SND_DEV_DSP16:
        case SND_DEV_AUDIO:
                audio_release(dev, file);
                break;

        default:
                printk(KERN_ERR "Sound error: Releasing unknown device 0x%02x\n", dev);
        }
        unlock_kernel();

        return 0;
}

static int get_mixer_info(int dev, void __user *arg)
{
        mixer_info info;
        memset(&info, 0, sizeof(info));
        strlcpy(info.id, mixer_devs[dev]->id, sizeof(info.id));
        strlcpy(info.name, mixer_devs[dev]->name, sizeof(info.name));
        info.modify_counter = mixer_devs[dev]->modify_counter;
        if (__copy_to_user(arg, &info,  sizeof(info)))
                return -EFAULT;
        return 0;
}

static int get_old_mixer_info(int dev, void __user *arg)
{
        _old_mixer_info info;
        memset(&info, 0, sizeof(info));
        strlcpy(info.id, mixer_devs[dev]->id, sizeof(info.id));
        strlcpy(info.name, mixer_devs[dev]->name, sizeof(info.name));
        if (copy_to_user(arg, &info,  sizeof(info)))
                return -EFAULT;
        return 0;
}

static int sound_mixer_ioctl(int mixdev, unsigned int cmd, void __user *arg)
{
        if (mixdev < 0 || mixdev >= MAX_MIXER_DEV)
                return -ENXIO;
        /* Try to load the mixer... */
        if (mixer_devs[mixdev] == NULL) {
                request_module("mixer%d", mixdev);
        }
        if (mixdev >= num_mixers || !mixer_devs[mixdev])
                return -ENXIO;
        if (cmd == SOUND_MIXER_INFO)
                return get_mixer_info(mixdev, arg);
        if (cmd == SOUND_OLD_MIXER_INFO)
                return get_old_mixer_info(mixdev, arg);
        if (_SIOC_DIR(cmd) & _SIOC_WRITE)
                mixer_devs[mixdev]->modify_counter++;
        if (!mixer_devs[mixdev]->ioctl)
                return -EINVAL;
        return mixer_devs[mixdev]->ioctl(mixdev, cmd, arg);
}

static int sound_ioctl(struct inode *inode, struct file *file,
                       unsigned int cmd, unsigned long arg)
{
        int len = 0, dtype;
        int dev = iminor(inode);
        void __user *p = (void __user *)arg;

        if (_SIOC_DIR(cmd) != _SIOC_NONE && _SIOC_DIR(cmd) != 0) {
                /*
                 * Have to validate the address given by the process.
                 */
                len = _SIOC_SIZE(cmd);
                if (len < 1 || len > 65536 || !p)
                        return -EFAULT;
                if (_SIOC_DIR(cmd) & _SIOC_WRITE)
                        if (!access_ok(VERIFY_READ, p, len))
                                return -EFAULT;
                if (_SIOC_DIR(cmd) & _SIOC_READ)
                        if (!access_ok(VERIFY_WRITE, p, len))
                                return -EFAULT;
        }
        DEB(printk("sound_ioctl(dev=%d, cmd=0x%x, arg=0x%x)\n", dev, cmd, arg));
        if (cmd == OSS_GETVERSION)
                return __put_user(SOUND_VERSION, (int __user *)p);
        
        if (_IOC_TYPE(cmd) == 'M' && num_mixers > 0 &&   /* Mixer ioctl */
            (dev & 0x0f) != SND_DEV_CTL) {              
                dtype = dev & 0x0f;
                switch (dtype) {
                case SND_DEV_DSP:
                case SND_DEV_DSP16:
                case SND_DEV_AUDIO:
                        return sound_mixer_ioctl(audio_devs[dev >> 4]->mixer_dev,
                                                 cmd, p);
                        
                default:
                        return sound_mixer_ioctl(dev >> 4, cmd, p);
                }
        }
        switch (dev & 0x0f) {
        case SND_DEV_CTL:
                if (cmd == SOUND_MIXER_GETLEVELS)
                        return get_mixer_levels(p);
                if (cmd == SOUND_MIXER_SETLEVELS)
                        return set_mixer_levels(p);
                return sound_mixer_ioctl(dev >> 4, cmd, p);

        case SND_DEV_SEQ:
        case SND_DEV_SEQ2:
                return sequencer_ioctl(dev, file, cmd, p);

        case SND_DEV_DSP:
        case SND_DEV_DSP16:
        case SND_DEV_AUDIO:
                return audio_ioctl(dev, file, cmd, p);
                break;

        case SND_DEV_MIDIN:
                return MIDIbuf_ioctl(dev, file, cmd, p);
                break;

        }
        return -EINVAL;
}

static unsigned int sound_poll(struct file *file, poll_table * wait)
{
        struct inode *inode = file->f_path.dentry->d_inode;
        int dev = iminor(inode);

        DEB(printk("sound_poll(dev=%d)\n", dev));
        switch (dev & 0x0f) {
        case SND_DEV_SEQ:
        case SND_DEV_SEQ2:
                return sequencer_poll(dev, file, wait);

        case SND_DEV_MIDIN:
                return MIDIbuf_poll(dev, file, wait);

        case SND_DEV_DSP:
        case SND_DEV_DSP16:
        case SND_DEV_AUDIO:
                return DMAbuf_poll(file, dev >> 4, wait);
        }
        return 0;
}

static int sound_mmap(struct file *file, struct vm_area_struct *vma)
{
        int dev_class;
        unsigned long size;
        struct dma_buffparms *dmap = NULL;
        int dev = iminor(file->f_path.dentry->d_inode);

        dev_class = dev & 0x0f;
        dev >>= 4;

        if (dev_class != SND_DEV_DSP && dev_class != SND_DEV_DSP16 && dev_class != SND_DEV_AUDIO) {
                printk(KERN_ERR "Sound: mmap() not supported for other than audio devices\n");
                return -EINVAL;
        }
        lock_kernel();
        if (vma->vm_flags & VM_WRITE)   /* Map write and read/write to the output buf */
                dmap = audio_devs[dev]->dmap_out;
        else if (vma->vm_flags & VM_READ)
                dmap = audio_devs[dev]->dmap_in;
        else {
                printk(KERN_ERR "Sound: Undefined mmap() access\n");
                unlock_kernel();
                return -EINVAL;
        }

        if (dmap == NULL) {
                printk(KERN_ERR "Sound: mmap() error. dmap == NULL\n");
                unlock_kernel();
                return -EIO;
        }
        if (dmap->raw_buf == NULL) {
                printk(KERN_ERR "Sound: mmap() called when raw_buf == NULL\n");
                unlock_kernel();
                return -EIO;
        }
        if (dmap->mapping_flags) {
                printk(KERN_ERR "Sound: mmap() called twice for the same DMA buffer\n");
                unlock_kernel();
                return -EIO;
        }
        if (vma->vm_pgoff != 0) {
                printk(KERN_ERR "Sound: mmap() offset must be 0.\n");
                unlock_kernel();
                return -EINVAL;
        }
        size = vma->vm_end - vma->vm_start;

        if (size != dmap->bytes_in_use) {
                printk(KERN_WARNING "Sound: mmap() size = %ld. Should be %d\n", size, dmap->bytes_in_use);
        }
        if (remap_pfn_range(vma, vma->vm_start,
                        virt_to_phys(dmap->raw_buf) >> PAGE_SHIFT,
                        vma->vm_end - vma->vm_start, vma->vm_page_prot)) {
                unlock_kernel();
                return -EAGAIN;
        }

        dmap->mapping_flags |= DMA_MAP_MAPPED;

        if( audio_devs[dev]->d->mmap)
                audio_devs[dev]->d->mmap(dev);

        memset(dmap->raw_buf,
               dmap->neutral_byte,
               dmap->bytes_in_use);
        unlock_kernel();
        return 0;
}

const struct file_operations oss_sound_fops = {
        .owner          = THIS_MODULE,
        .llseek         = no_llseek,
        .read           = sound_read,
        .write          = sound_write,
        .poll           = sound_poll,
        .ioctl          = sound_ioctl,
        .mmap           = sound_mmap,
        .open           = sound_open,
        .release        = sound_release,
};

/*
 *      Create the required special subdevices
 */
 
static int create_special_devices(void)
{
        int seq1,seq2;
        seq1=register_sound_special(&oss_sound_fops, 1);
        if(seq1==-1)
                goto bad;
        seq2=register_sound_special(&oss_sound_fops, 8);
        if(seq2!=-1)
                return 0;
        unregister_sound_special(1);
bad:
        return -1;
}


/* These device names follow the official Linux device list,
 * Documentation/devices.txt.  Let us know if there are other
 * common names we should support for compatibility.
 * Only those devices not created by the generic code in sound_core.c are
 * registered here.
 */
static const struct {
        unsigned short minor;
        char *name;
        umode_t mode;
        int *num;
} dev_list[] = { /* list of minor devices */
/* seems to be some confusion here -- this device is not in the device list */
        {SND_DEV_DSP16,     "dspW",      S_IWUGO | S_IRUSR | S_IRGRP,
         &num_audiodevs},
        {SND_DEV_AUDIO,     "audio",     S_IWUGO | S_IRUSR | S_IRGRP,
         &num_audiodevs},
};

static int dmabuf;
static int dmabug;

module_param(dmabuf, int, 0444);
module_param(dmabug, int, 0444);

static int __init oss_init(void)
{
        int             err;
        int i, j;
        
#ifdef CONFIG_PCI
        if(dmabug)
                isa_dma_bridge_buggy = dmabug;
#endif

        err = create_special_devices();
        if (err) {
                printk(KERN_ERR "sound: driver already loaded/included in kernel\n");
                return err;
        }

        /* Protecting the innocent */
        sound_dmap_flag = (dmabuf > 0 ? 1 : 0);

        for (i = 0; i < ARRAY_SIZE(dev_list); i++) {
                device_create_drvdata(sound_class, NULL,
                                      MKDEV(SOUND_MAJOR, dev_list[i].minor),
                                      NULL, "%s", dev_list[i].name);

                if (!dev_list[i].num)
                        continue;

                for (j = 1; j < *dev_list[i].num; j++)
                        device_create_drvdata(sound_class, NULL,
                                              MKDEV(SOUND_MAJOR,
                                                    dev_list[i].minor + (j*0x10)),
                                              NULL,
                                              "%s%d", dev_list[i].name, j);
        }

        if (sound_nblocks >= 1024)
                printk(KERN_ERR "Sound warning: Deallocation table was too small.\n");
        
        return 0;
}

static void __exit oss_cleanup(void)
{
        int i, j;

        for (i = 0; i < ARRAY_SIZE(dev_list); i++) {
                device_destroy(sound_class, MKDEV(SOUND_MAJOR, dev_list[i].minor));
                if (!dev_list[i].num)
                        continue;
                for (j = 1; j < *dev_list[i].num; j++)
                        device_destroy(sound_class, MKDEV(SOUND_MAJOR, dev_list[i].minor + (j*0x10)));
        }
        
        unregister_sound_special(1);
        unregister_sound_special(8);

        sound_stop_timer();

        sequencer_unload();

        for (i = 0; i < MAX_DMA_CHANNELS; i++)
                if (dma_alloc_map[i] != DMA_MAP_UNAVAIL) {
                        printk(KERN_ERR "Sound: Hmm, DMA%d was left allocated - fixed\n", i);
                        sound_free_dma(i);
                }

        for (i = 0; i < sound_nblocks; i++)
                vfree(sound_mem_blocks[i]);

}

module_init(oss_init);
module_exit(oss_cleanup);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("OSS Sound subsystem");
MODULE_AUTHOR("Hannu Savolainen, et al.");


int sound_alloc_dma(int chn, char *deviceID)
{
        int err;

        if ((err = request_dma(chn, deviceID)) != 0)
                return err;

        dma_alloc_map[chn] = DMA_MAP_FREE;

        return 0;
}
EXPORT_SYMBOL(sound_alloc_dma);

int sound_open_dma(int chn, char *deviceID)
{
        if (!valid_dma(chn)) {
                printk(KERN_ERR "sound_open_dma: Invalid DMA channel %d\n", chn);
                return 1;
        }

        if (dma_alloc_map[chn] != DMA_MAP_FREE) {
                printk("sound_open_dma: DMA channel %d busy or not allocated (%d)\n", chn, dma_alloc_map[chn]);
                return 1;
        }
        dma_alloc_map[chn] = DMA_MAP_BUSY;
        return 0;
}
EXPORT_SYMBOL(sound_open_dma);

void sound_free_dma(int chn)
{
        if (dma_alloc_map[chn] == DMA_MAP_UNAVAIL) {
                /* printk( "sound_free_dma: Bad access to DMA channel %d\n",  chn); */
                return;
        }
        free_dma(chn);
        dma_alloc_map[chn] = DMA_MAP_UNAVAIL;
}
EXPORT_SYMBOL(sound_free_dma);

void sound_close_dma(int chn)
{
        if (dma_alloc_map[chn] != DMA_MAP_BUSY) {
                printk(KERN_ERR "sound_close_dma: Bad access to DMA channel %d\n", chn);
                return;
        }
        dma_alloc_map[chn] = DMA_MAP_FREE;
}
EXPORT_SYMBOL(sound_close_dma);

static void do_sequencer_timer(unsigned long dummy)
{
        sequencer_timer(0);
}


static DEFINE_TIMER(seq_timer, do_sequencer_timer, 0, 0);

void request_sound_timer(int count)
{
        extern unsigned long seq_time;

        if (count < 0) {
                seq_timer.expires = (-count) + jiffies;
                add_timer(&seq_timer);
                return;
        }
        count += seq_time;

        count -= jiffies;

        if (count < 1)
                count = 1;

        seq_timer.expires = (count) + jiffies;
        add_timer(&seq_timer);
}

void sound_stop_timer(void)
{
        del_timer(&seq_timer);
}

void conf_printf(char *name, struct address_info *hw_config)
{
#ifndef CONFIG_SOUND_TRACEINIT
        return;
#else
        printk("<%s> at 0x%03x", name, hw_config->io_base);

        if (hw_config->irq)
                printk(" irq %d", (hw_config->irq > 0) ? hw_config->irq : -hw_config->irq);

        if (hw_config->dma != -1 || hw_config->dma2 != -1)
        {
                printk(" dma %d", hw_config->dma);
                if (hw_config->dma2 != -1)
                        printk(",%d", hw_config->dma2);
        }
        printk("\n");
#endif
}
EXPORT_SYMBOL(conf_printf);

void conf_printf2(char *name, int base, int irq, int dma, int dma2)
{
#ifndef CONFIG_SOUND_TRACEINIT
        return;
#else
        printk("<%s> at 0x%03x", name, base);

        if (irq)
                printk(" irq %d", (irq > 0) ? irq : -irq);

        if (dma != -1 || dma2 != -1)
        {
                  printk(" dma %d", dma);
                  if (dma2 != -1)
                          printk(",%d", dma2);
        }
        printk("\n");
#endif
}
EXPORT_SYMBOL(conf_printf2);


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