linux/arch/um/drivers/hostaudio_kern.c
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   1/*
   2 * Copyright (C) 2002 Steve Schmidtke
   3 * Licensed under the GPL
   4 */
   5
   6#include "linux/fs.h"
   7#include "linux/module.h"
   8#include "linux/slab.h"
   9#include "linux/sound.h"
  10#include "linux/soundcard.h"
  11#include "linux/mutex.h"
  12#include "asm/uaccess.h"
  13#include "init.h"
  14#include "os.h"
  15
  16struct hostaudio_state {
  17        int fd;
  18};
  19
  20struct hostmixer_state {
  21        int fd;
  22};
  23
  24#define HOSTAUDIO_DEV_DSP "/dev/sound/dsp"
  25#define HOSTAUDIO_DEV_MIXER "/dev/sound/mixer"
  26
  27/*
  28 * Changed either at boot time or module load time.  At boot, this is
  29 * single-threaded; at module load, multiple modules would each have
  30 * their own copy of these variables.
  31 */
  32static char *dsp = HOSTAUDIO_DEV_DSP;
  33static char *mixer = HOSTAUDIO_DEV_MIXER;
  34
  35#define DSP_HELP \
  36"    This is used to specify the host dsp device to the hostaudio driver.\n" \
  37"    The default is \"" HOSTAUDIO_DEV_DSP "\".\n\n"
  38
  39#define MIXER_HELP \
  40"    This is used to specify the host mixer device to the hostaudio driver.\n"\
  41"    The default is \"" HOSTAUDIO_DEV_MIXER "\".\n\n"
  42
  43module_param(dsp, charp, 0644);
  44MODULE_PARM_DESC(dsp, DSP_HELP);
  45module_param(mixer, charp, 0644);
  46MODULE_PARM_DESC(mixer, MIXER_HELP);
  47
  48#ifndef MODULE
  49static int set_dsp(char *name, int *add)
  50{
  51        dsp = name;
  52        return 0;
  53}
  54
  55__uml_setup("dsp=", set_dsp, "dsp=<dsp device>\n" DSP_HELP);
  56
  57static int set_mixer(char *name, int *add)
  58{
  59        mixer = name;
  60        return 0;
  61}
  62
  63__uml_setup("mixer=", set_mixer, "mixer=<mixer device>\n" MIXER_HELP);
  64#endif
  65
  66static DEFINE_MUTEX(hostaudio_mutex);
  67
  68/* /dev/dsp file operations */
  69
  70static ssize_t hostaudio_read(struct file *file, char __user *buffer,
  71                              size_t count, loff_t *ppos)
  72{
  73        struct hostaudio_state *state = file->private_data;
  74        void *kbuf;
  75        int err;
  76
  77#ifdef DEBUG
  78        printk(KERN_DEBUG "hostaudio: read called, count = %d\n", count);
  79#endif
  80
  81        kbuf = kmalloc(count, GFP_KERNEL);
  82        if (kbuf == NULL)
  83                return -ENOMEM;
  84
  85        err = os_read_file(state->fd, kbuf, count);
  86        if (err < 0)
  87                goto out;
  88
  89        if (copy_to_user(buffer, kbuf, err))
  90                err = -EFAULT;
  91
  92out:
  93        kfree(kbuf);
  94        return err;
  95}
  96
  97static ssize_t hostaudio_write(struct file *file, const char __user *buffer,
  98                               size_t count, loff_t *ppos)
  99{
 100        struct hostaudio_state *state = file->private_data;
 101        void *kbuf;
 102        int err;
 103
 104#ifdef DEBUG
 105        printk(KERN_DEBUG "hostaudio: write called, count = %d\n", count);
 106#endif
 107
 108        kbuf = kmalloc(count, GFP_KERNEL);
 109        if (kbuf == NULL)
 110                return -ENOMEM;
 111
 112        err = -EFAULT;
 113        if (copy_from_user(kbuf, buffer, count))
 114                goto out;
 115
 116        err = os_write_file(state->fd, kbuf, count);
 117        if (err < 0)
 118                goto out;
 119        *ppos += err;
 120
 121 out:
 122        kfree(kbuf);
 123        return err;
 124}
 125
 126static unsigned int hostaudio_poll(struct file *file,
 127                                   struct poll_table_struct *wait)
 128{
 129        unsigned int mask = 0;
 130
 131#ifdef DEBUG
 132        printk(KERN_DEBUG "hostaudio: poll called (unimplemented)\n");
 133#endif
 134
 135        return mask;
 136}
 137
 138static long hostaudio_ioctl(struct file *file,
 139                           unsigned int cmd, unsigned long arg)
 140{
 141        struct hostaudio_state *state = file->private_data;
 142        unsigned long data = 0;
 143        int err;
 144
 145#ifdef DEBUG
 146        printk(KERN_DEBUG "hostaudio: ioctl called, cmd = %u\n", cmd);
 147#endif
 148        switch(cmd){
 149        case SNDCTL_DSP_SPEED:
 150        case SNDCTL_DSP_STEREO:
 151        case SNDCTL_DSP_GETBLKSIZE:
 152        case SNDCTL_DSP_CHANNELS:
 153        case SNDCTL_DSP_SUBDIVIDE:
 154        case SNDCTL_DSP_SETFRAGMENT:
 155                if (get_user(data, (int __user *) arg))
 156                        return -EFAULT;
 157                break;
 158        default:
 159                break;
 160        }
 161
 162        err = os_ioctl_generic(state->fd, cmd, (unsigned long) &data);
 163
 164        switch(cmd){
 165        case SNDCTL_DSP_SPEED:
 166        case SNDCTL_DSP_STEREO:
 167        case SNDCTL_DSP_GETBLKSIZE:
 168        case SNDCTL_DSP_CHANNELS:
 169        case SNDCTL_DSP_SUBDIVIDE:
 170        case SNDCTL_DSP_SETFRAGMENT:
 171                if (put_user(data, (int __user *) arg))
 172                        return -EFAULT;
 173                break;
 174        default:
 175                break;
 176        }
 177
 178        return err;
 179}
 180
 181static int hostaudio_open(struct inode *inode, struct file *file)
 182{
 183        struct hostaudio_state *state;
 184        int r = 0, w = 0;
 185        int ret;
 186
 187#ifdef DEBUG
 188        kparam_block_sysfs_write(dsp);
 189        printk(KERN_DEBUG "hostaudio: open called (host: %s)\n", dsp);
 190        kparam_unblock_sysfs_write(dsp);
 191#endif
 192
 193        state = kmalloc(sizeof(struct hostaudio_state), GFP_KERNEL);
 194        if (state == NULL)
 195                return -ENOMEM;
 196
 197        if (file->f_mode & FMODE_READ)
 198                r = 1;
 199        if (file->f_mode & FMODE_WRITE)
 200                w = 1;
 201
 202        kparam_block_sysfs_write(dsp);
 203        mutex_lock(&hostaudio_mutex);
 204        ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0);
 205        mutex_unlock(&hostaudio_mutex);
 206        kparam_unblock_sysfs_write(dsp);
 207
 208        if (ret < 0) {
 209                kfree(state);
 210                return ret;
 211        }
 212        state->fd = ret;
 213        file->private_data = state;
 214        return 0;
 215}
 216
 217static int hostaudio_release(struct inode *inode, struct file *file)
 218{
 219        struct hostaudio_state *state = file->private_data;
 220
 221#ifdef DEBUG
 222        printk(KERN_DEBUG "hostaudio: release called\n");
 223#endif
 224        os_close_file(state->fd);
 225        kfree(state);
 226
 227        return 0;
 228}
 229
 230/* /dev/mixer file operations */
 231
 232static long hostmixer_ioctl_mixdev(struct file *file,
 233                                  unsigned int cmd, unsigned long arg)
 234{
 235        struct hostmixer_state *state = file->private_data;
 236
 237#ifdef DEBUG
 238        printk(KERN_DEBUG "hostmixer: ioctl called\n");
 239#endif
 240
 241        return os_ioctl_generic(state->fd, cmd, arg);
 242}
 243
 244static int hostmixer_open_mixdev(struct inode *inode, struct file *file)
 245{
 246        struct hostmixer_state *state;
 247        int r = 0, w = 0;
 248        int ret;
 249
 250#ifdef DEBUG
 251        printk(KERN_DEBUG "hostmixer: open called (host: %s)\n", mixer);
 252#endif
 253
 254        state = kmalloc(sizeof(struct hostmixer_state), GFP_KERNEL);
 255        if (state == NULL)
 256                return -ENOMEM;
 257
 258        if (file->f_mode & FMODE_READ)
 259                r = 1;
 260        if (file->f_mode & FMODE_WRITE)
 261                w = 1;
 262
 263        kparam_block_sysfs_write(mixer);
 264        mutex_lock(&hostaudio_mutex);
 265        ret = os_open_file(mixer, of_set_rw(OPENFLAGS(), r, w), 0);
 266        mutex_unlock(&hostaudio_mutex);
 267        kparam_unblock_sysfs_write(mixer);
 268
 269        if (ret < 0) {
 270                kparam_block_sysfs_write(dsp);
 271                printk(KERN_ERR "hostaudio_open_mixdev failed to open '%s', "
 272                       "err = %d\n", dsp, -ret);
 273                kparam_unblock_sysfs_write(dsp);
 274                kfree(state);
 275                return ret;
 276        }
 277
 278        file->private_data = state;
 279        return 0;
 280}
 281
 282static int hostmixer_release(struct inode *inode, struct file *file)
 283{
 284        struct hostmixer_state *state = file->private_data;
 285
 286#ifdef DEBUG
 287        printk(KERN_DEBUG "hostmixer: release called\n");
 288#endif
 289
 290        os_close_file(state->fd);
 291        kfree(state);
 292
 293        return 0;
 294}
 295
 296/* kernel module operations */
 297
 298static const struct file_operations hostaudio_fops = {
 299        .owner          = THIS_MODULE,
 300        .llseek         = no_llseek,
 301        .read           = hostaudio_read,
 302        .write          = hostaudio_write,
 303        .poll           = hostaudio_poll,
 304        .unlocked_ioctl = hostaudio_ioctl,
 305        .mmap           = NULL,
 306        .open           = hostaudio_open,
 307        .release        = hostaudio_release,
 308};
 309
 310static const struct file_operations hostmixer_fops = {
 311        .owner          = THIS_MODULE,
 312        .llseek         = no_llseek,
 313        .unlocked_ioctl = hostmixer_ioctl_mixdev,
 314        .open           = hostmixer_open_mixdev,
 315        .release        = hostmixer_release,
 316};
 317
 318struct {
 319        int dev_audio;
 320        int dev_mixer;
 321} module_data;
 322
 323MODULE_AUTHOR("Steve Schmidtke");
 324MODULE_DESCRIPTION("UML Audio Relay");
 325MODULE_LICENSE("GPL");
 326
 327static int __init hostaudio_init_module(void)
 328{
 329        __kernel_param_lock();
 330        printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n",
 331               dsp, mixer);
 332        __kernel_param_unlock();
 333
 334        module_data.dev_audio = register_sound_dsp(&hostaudio_fops, -1);
 335        if (module_data.dev_audio < 0) {
 336                printk(KERN_ERR "hostaudio: couldn't register DSP device!\n");
 337                return -ENODEV;
 338        }
 339
 340        module_data.dev_mixer = register_sound_mixer(&hostmixer_fops, -1);
 341        if (module_data.dev_mixer < 0) {
 342                printk(KERN_ERR "hostmixer: couldn't register mixer "
 343                       "device!\n");
 344                unregister_sound_dsp(module_data.dev_audio);
 345                return -ENODEV;
 346        }
 347
 348        return 0;
 349}
 350
 351static void __exit hostaudio_cleanup_module (void)
 352{
 353        unregister_sound_mixer(module_data.dev_mixer);
 354        unregister_sound_dsp(module_data.dev_audio);
 355}
 356
 357module_init(hostaudio_init_module);
 358module_exit(hostaudio_cleanup_module);
 359
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