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 /* 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  */
  32 static char *dsp = HOSTAUDIO_DEV_DSP;
  33 static 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
  43 #ifndef MODULE
  44 static int set_dsp(char *name, int *add)
  45 {
  46         dsp = name;
  47         return(0);
  48 }
  49
  50 __uml_setup("dsp=", set_dsp, "dsp=<dsp device>\n" DSP_HELP);
  51
  52 static int set_mixer(char *name, int *add)
  53 {
  54         mixer = name;
  55         return(0);
  56 }
  57
  58 __uml_setup("mixer=", set_mixer, "mixer=<mixer device>\n" MIXER_HELP);
  59
  60 #else /*MODULE*/
  61
  62 module_param(dsp, charp, 0644);
  63 MODULE_PARM_DESC(dsp, DSP_HELP);
  64
  65 module_param(mixer, charp, 0644);
  66 MODULE_PARM_DESC(mixer, MIXER_HELP);
  67
  68 #endif
  69
  70 /* /dev/dsp file operations */
  71
  72 static ssize_t hostaudio_read(struct file *file, char __user *buffer,
  73                               size_t count, loff_t *ppos)
  74 {
  75         struct hostaudio_state *state = file->private_data;
  76         void *kbuf;
  77         int err;
  78
  79 #ifdef DEBUG
  80         printk("hostaudio: read called, count = %d\n", count);
  81 #endif
  82
  83         kbuf = kmalloc(count, GFP_KERNEL);
  84         if(kbuf == NULL)
  85                 return(-ENOMEM);
  86
  87         err = os_read_file(state->fd, kbuf, count);
  88         if(err < 0)
  89                 goto out;
  90
  91         if(copy_to_user(buffer, kbuf, err))
  92                 err = -EFAULT;
  93
  94 out:
  95         kfree(kbuf);
  96         return(err);
  97 }
  98
  99 static ssize_t hostaudio_write(struct file *file, const char __user *buffer,
 100                                size_t count, loff_t *ppos)
 101 {
 102         struct hostaudio_state *state = file->private_data;
 103         void *kbuf;
 104         int err;
 105
 106 #ifdef DEBUG
 107         printk("hostaudio: write called, count = %d\n", count);
 108 #endif
 109
 110         kbuf = kmalloc(count, GFP_KERNEL);
 111         if(kbuf == NULL)
 112                 return(-ENOMEM);
 113
 114         err = -EFAULT;
 115         if(copy_from_user(kbuf, buffer, count))
 116                 goto out;
 117
 118         err = os_write_file(state->fd, kbuf, count);
 119         if(err < 0)
 120                 goto out;
 121         *ppos += err;
 122
 123  out:
 124         kfree(kbuf);
 125         return(err);
 126 }
 127
 128 static unsigned int hostaudio_poll(struct file *file,
 129                                    struct poll_table_struct *wait)
 130 {
 131         unsigned int mask = 0;
 132
 133 #ifdef DEBUG
 134         printk("hostaudio: poll called (unimplemented)\n");
 135 #endif
 136
 137         return(mask);
 138 }
 139
 140 static int hostaudio_ioctl(struct inode *inode, struct file *file,
 141                            unsigned int cmd, unsigned long arg)
 142 {
 143         struct hostaudio_state *state = file->private_data;
 144         unsigned long data = 0;
 145         int err;
 146
 147 #ifdef DEBUG
 148         printk("hostaudio: ioctl called, cmd = %u\n", cmd);
 149 #endif
 150         switch(cmd){
 151         case SNDCTL_DSP_SPEED:
 152         case SNDCTL_DSP_STEREO:
 153         case SNDCTL_DSP_GETBLKSIZE:
 154         case SNDCTL_DSP_CHANNELS:
 155         case SNDCTL_DSP_SUBDIVIDE:
 156         case SNDCTL_DSP_SETFRAGMENT:
 157                 if(get_user(data, (int __user *) arg))
 158                         return(-EFAULT);
 159                 break;
 160         default:
 161                 break;
 162         }
 163
 164         err = os_ioctl_generic(state->fd, cmd, (unsigned long) &data);
 165
 166         switch(cmd){
 167         case SNDCTL_DSP_SPEED:
 168         case SNDCTL_DSP_STEREO:
 169         case SNDCTL_DSP_GETBLKSIZE:
 170         case SNDCTL_DSP_CHANNELS:
 171         case SNDCTL_DSP_SUBDIVIDE:
 172         case SNDCTL_DSP_SETFRAGMENT:
 173                 if(put_user(data, (int __user *) arg))
 174                         return(-EFAULT);
 175                 break;
 176         default:
 177                 break;
 178         }
 179
 180         return(err);
 181 }
 182
 183 static int hostaudio_open(struct inode *inode, struct file *file)
 184 {
 185         struct hostaudio_state *state;
 186         int r = 0, w = 0;
 187         int ret;
 188
 189 #ifdef DEBUG
 190         printk("hostaudio: open called (host: %s)\n", 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) r = 1;
 198         if(file->f_mode & FMODE_WRITE) w = 1;
 199
 200         ret = os_open_file(dsp, of_set_rw(OPENFLAGS(), r, w), 0);
 201         if(ret < 0){
 202                 kfree(state);
 203                 return(ret);
 204         }
 205         state->fd = ret;
 206         file->private_data = state;
 207         return(0);
 208 }
 209
 210 static int hostaudio_release(struct inode *inode, struct file *file)
 211 {
 212         struct hostaudio_state *state = file->private_data;
 213
 214 #ifdef DEBUG
 215         printk("hostaudio: release called\n");
 216 #endif
 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 /* 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);