arch/um/drivers/hostaudio_kern.c

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