arch/um/drivers/hostaudio_kern.c

   1 /*
   2  * Copyright (C) 2002 Steve Schmidtke
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/config.h"
   7 #include "linux/module.h"
   8 #include "linux/init.h"
   9 #include "linux/slab.h"
  10 #include "linux/fs.h"
  11 #include "linux/sound.h"
  12 #include "linux/soundcard.h"
  13 #include "asm/uaccess.h"
  14 #include "kern_util.h"
  15 #include "init.h"
  16 #include "os.h"
  17
  18 struct hostaudio_state {
  19   int fd;
  20 };
  21
  22 struct hostmixer_state {
  23   int fd;
  24 };
  25
  26 #define HOSTAUDIO_DEV_DSP "/dev/sound/dsp"
  27 #define HOSTAUDIO_DEV_MIXER "/dev/sound/mixer"
  28
  29 /* Only changed from linux_main at boot time */
  30 char *dsp = HOSTAUDIO_DEV_DSP;
  31 char *mixer = HOSTAUDIO_DEV_MIXER;
  32
  33 #define DSP_HELP \
  34 "    This is used to specify the host dsp device to the hostaudio driver.\n" \
  35 "    The default is \"" HOSTAUDIO_DEV_DSP "\".\n\n"
  36
  37 #define MIXER_HELP \
  38 "    This is used to specify the host mixer device to the hostaudio driver.\n"\
  39 "    The default is \"" HOSTAUDIO_DEV_MIXER "\".\n\n"
  40
  41 #ifndef MODULE
  42 static int set_dsp(char *name, int *add)
  43 {
  44         dsp = name;
  45         return(0);
  46 }
  47
  48 __uml_setup("dsp=", set_dsp, "dsp=<dsp device>\n" DSP_HELP);
  49
  50 static int set_mixer(char *name, int *add)
  51 {
  52         mixer = name;
  53         return(0);
  54 }
  55
  56 __uml_setup("mixer=", set_mixer, "mixer=<mixer device>\n" MIXER_HELP);
  57
  58 #else /*MODULE*/
  59
  60 module_param(dsp, charp, 0644);
  61 MODULE_PARM_DESC(dsp, DSP_HELP);
  62
  63 module_param(mixer, charp, 0644);
  64 MODULE_PARM_DESC(mixer, MIXER_HELP);
  65
  66 #endif
  67
  68 /* /dev/dsp file operations */
  69
  70 static 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("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
  92  out:
  93         kfree(kbuf);
  94         return(err);
  95 }
  96
  97 static 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("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
 126 static 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("hostaudio: poll called (unimplemented)\n");
 133 #endif
 134
 135         return(mask);
 136 }
 137
 138 static int hostaudio_ioctl(struct inode *inode, 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("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
 181 static 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         printk("hostaudio: open called (host: %s)\n", dsp);
 189 #endif
 190
 191         state = kmalloc(sizeof(struct hostaudio_state), GFP_KERNEL);
 192         if(state == NULL)
 193                 return(-ENOMEM);
 194
 195         if(file->f_mode & FMODE_READ) r = 1;
 196         if(file->f_mode & FMODE_WRITE) w = 1;
 197
 198         ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0);
 199         if(ret < 0){
 200                 kfree(state);
 201                 return(ret);
 202         }
 203
 204         state->fd = ret;
 205         file->private_data = state;
 206         return(0);
 207 }
 208
 209 static int hostaudio_release(struct inode *inode, struct file *file)
 210 {
 211         struct hostaudio_state *state = file->private_data;
 212
 213 #ifdef DEBUG
 214         printk("hostaudio: release called\n");
 215 #endif
 216
 217                 os_close_file(state->fd);
 218         kfree(state);
 219
 220         return(0);
 221 }
 222
 223 /* /dev/mixer file operations */
 224
 225 static int hostmixer_ioctl_mixdev(struct inode *inode, struct file *file,
 226                                   unsigned int cmd, unsigned long arg)
 227 {
 228         struct hostmixer_state *state = file->private_data;
 229
 230 #ifdef DEBUG
 231         printk("hostmixer: ioctl called\n");
 232 #endif
 233
 234         return(os_ioctl_generic(state->fd, cmd, arg));
 235 }
 236
 237 static int hostmixer_open_mixdev(struct inode *inode, struct file *file)
 238 {
 239         struct hostmixer_state *state;
 240         int r = 0, w = 0;
 241         int ret;
 242
 243 #ifdef DEBUG
 244         printk("hostmixer: open called (host: %s)\n", mixer);
 245 #endif
 246
 247         state = kmalloc(sizeof(struct hostmixer_state), GFP_KERNEL);
 248         if(state == NULL) return(-ENOMEM);
 249
 250         if(file->f_mode & FMODE_READ) r = 1;
 251         if(file->f_mode & FMODE_WRITE) w = 1;
 252
 253         ret = os_open_file(mixer, of_set_rw(OPENFLAGS(), r, w), 0);
 254
 255         if(ret < 0){
 256                 printk("hostaudio_open_mixdev failed to open '%s', err = %d\n",
 257                        dsp, -ret);
 258                 kfree(state);
 259                 return(ret);
 260         }
 261
 262         file->private_data = state;
 263         return(0);
 264 }
 265
 266 static int hostmixer_release(struct inode *inode, struct file *file)
 267 {
 268         struct hostmixer_state *state = file->private_data;
 269
 270 #ifdef DEBUG
 271         printk("hostmixer: release called\n");
 272 #endif
 273
 274                 os_close_file(state->fd);
 275         kfree(state);
 276
 277         return(0);
 278 }
 279
 280
 281 /* kernel module operations */
 282
 283 static struct file_operations hostaudio_fops = {
 284         .owner          = THIS_MODULE,
 285         .llseek         = no_llseek,
 286         .read           = hostaudio_read,
 287         .write          = hostaudio_write,
 288         .poll           = hostaudio_poll,
 289         .ioctl          = hostaudio_ioctl,
 290         .mmap           = NULL,
 291         .open           = hostaudio_open,
 292         .release        = hostaudio_release,
 293 };
 294
 295 static struct file_operations hostmixer_fops = {
 296         .owner          = THIS_MODULE,
 297         .llseek         = no_llseek,
 298         .ioctl          = hostmixer_ioctl_mixdev,
 299         .open           = hostmixer_open_mixdev,
 300         .release        = hostmixer_release,
 301 };
 302
 303 struct {
 304         int dev_audio;
 305         int dev_mixer;
 306 } module_data;
 307
 308 MODULE_AUTHOR("Steve Schmidtke");
 309 MODULE_DESCRIPTION("UML Audio Relay");
 310 MODULE_LICENSE("GPL");
 311
 312 static int __init hostaudio_init_module(void)
 313 {
 314         printk(KERN_INFO "UML Audio Relay (host dsp = %s, host mixer = %s)\n",
 315                dsp, mixer);
 316
 317         module_data.dev_audio = register_sound_dsp(&hostaudio_fops, -1);
 318         if(module_data.dev_audio < 0){
 319                 printk(KERN_ERR "hostaudio: couldn't register DSP device!\n");
 320                 return -ENODEV;
 321         }
 322
 323         module_data.dev_mixer = register_sound_mixer(&hostmixer_fops, -1);
 324         if(module_data.dev_mixer < 0){
 325                 printk(KERN_ERR "hostmixer: couldn't register mixer "
 326                        "device!\n");
 327                 unregister_sound_dsp(module_data.dev_audio);
 328                 return -ENODEV;
 329         }
 330
 331         return 0;
 332 }
 333
 334 static void __exit hostaudio_cleanup_module (void)
 335 {
 336        unregister_sound_mixer(module_data.dev_mixer);
 337        unregister_sound_dsp(module_data.dev_audio);
 338 }
 339
 340 module_init(hostaudio_init_module);
 341 module_exit(hostaudio_cleanup_module);
 342
 343 /*
 344  * Overrides for Emacs so that we follow Linus's tabbing style.
 345  * Emacs will notice this stuff at the end of the file and automatically
 346  * adjust the settings for this buffer only.  This must remain at the end
 347  * of the file.
 348  * ---------------------------------------------------------------------------
 349  * Local variables:
 350  * c-file-style: "linux"
 351  * End:
 352  */