arch/um/drivers/hostaudio_kern.c

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