sound/oss/sh_dac_audio.c

   1 /*
   2  * sound/oss/sh_dac_audio.c
   3  *
   4  * SH DAC based sound :(
   5  *
   6  *  Copyright (C) 2004,2005  Andriy Skulysh
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file "COPYING" in the main directory of this archive
  10  * for more details.
  11  */
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/sched.h>
  15 #include <linux/linkage.h>
  16 #include <linux/slab.h>
  17 #include <linux/fs.h>
  18 #include <linux/sound.h>
  19 #include <linux/soundcard.h>
  20 #include <linux/interrupt.h>
  21 #include <asm/io.h>
  22 #include <asm/uaccess.h>
  23 #include <asm/irq.h>
  24 #include <asm/delay.h>
  25 #include <asm/clock.h>
  26 #include <asm/cpu/dac.h>
  27 #include <asm/cpu/timer.h>
  28 #include <asm/machvec.h>
  29 #include <asm/hp6xx.h>
  30 #include <asm/hd64461.h>
  31
  32 #define MODNAME "sh_dac_audio"
  33
  34 #define TMU_TOCR_INIT   0x00
  35
  36 #define TMU1_TCR_INIT   0x0020  /* Clock/4, rising edge; interrupt on */
  37 #define TMU1_TSTR_INIT  0x02    /* Bit to turn on TMU1 */
  38
  39 #define BUFFER_SIZE 48000
  40
  41 static int rate;
  42 static int empty;
  43 static char *data_buffer, *buffer_begin, *buffer_end;
  44 static int in_use, device_major;
  45
  46 static void dac_audio_start_timer(void)
  47 {
  48         u8 tstr;
  49
  50         tstr = ctrl_inb(TMU_TSTR);
  51         tstr |= TMU1_TSTR_INIT;
  52         ctrl_outb(tstr, TMU_TSTR);
  53 }
  54
  55 static void dac_audio_stop_timer(void)
  56 {
  57         u8 tstr;
  58
  59         tstr = ctrl_inb(TMU_TSTR);
  60         tstr &= ~TMU1_TSTR_INIT;
  61         ctrl_outb(tstr, TMU_TSTR);
  62 }
  63
  64 static void dac_audio_reset(void)
  65 {
  66         dac_audio_stop_timer();
  67         buffer_begin = buffer_end = data_buffer;
  68         empty = 1;
  69 }
  70
  71 static void dac_audio_sync(void)
  72 {
  73         while (!empty)
  74                 schedule();
  75 }
  76
  77 static void dac_audio_start(void)
  78 {
  79         if (mach_is_hp6xx()) {
  80                 u16 v = inw(HD64461_GPADR);
  81                 v &= ~HD64461_GPADR_SPEAKER;
  82                 outw(v, HD64461_GPADR);
  83         }
  84
  85         sh_dac_enable(CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
  86         ctrl_outw(TMU1_TCR_INIT, TMU1_TCR);
  87 }
  88 static void dac_audio_stop(void)
  89 {
  90         dac_audio_stop_timer();
  91
  92         if (mach_is_hp6xx()) {
  93                 u16 v = inw(HD64461_GPADR);
  94                 v |= HD64461_GPADR_SPEAKER;
  95                 outw(v, HD64461_GPADR);
  96         }
  97
  98         sh_dac_output(0, CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
  99         sh_dac_disable(CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
 100 }
 101
 102 static void dac_audio_set_rate(void)
 103 {
 104         unsigned long interval;
 105         struct clk *clk;
 106
 107         clk = clk_get(NULL, "module_clk");
 108         interval = (clk_get_rate(clk) / 4) / rate;
 109         clk_put(clk);
 110         ctrl_outl(interval, TMU1_TCOR);
 111         ctrl_outl(interval, TMU1_TCNT);
 112 }
 113
 114 static int dac_audio_ioctl(struct inode *inode, struct file *file,
 115                            unsigned int cmd, unsigned long arg)
 116 {
 117         int val;
 118
 119         switch (cmd) {
 120         case OSS_GETVERSION:
 121                 return put_user(SOUND_VERSION, (int *)arg);
 122
 123         case SNDCTL_DSP_SYNC:
 124                 dac_audio_sync();
 125                 return 0;
 126
 127         case SNDCTL_DSP_RESET:
 128                 dac_audio_reset();
 129                 return 0;
 130
 131         case SNDCTL_DSP_GETFMTS:
 132                 return put_user(AFMT_U8, (int *)arg);
 133
 134         case SNDCTL_DSP_SETFMT:
 135                 return put_user(AFMT_U8, (int *)arg);
 136
 137         case SNDCTL_DSP_NONBLOCK:
 138                 file->f_flags |= O_NONBLOCK;
 139                 return 0;
 140
 141         case SNDCTL_DSP_GETCAPS:
 142                 return 0;
 143
 144         case SOUND_PCM_WRITE_RATE:
 145                 val = *(int *)arg;
 146                 if (val > 0) {
 147                         rate = val;
 148                         dac_audio_set_rate();
 149                 }
 150                 return put_user(rate, (int *)arg);
 151
 152         case SNDCTL_DSP_STEREO:
 153                 return put_user(0, (int *)arg);
 154
 155         case SOUND_PCM_WRITE_CHANNELS:
 156                 return put_user(1, (int *)arg);
 157
 158         case SNDCTL_DSP_SETDUPLEX:
 159                 return -EINVAL;
 160
 161         case SNDCTL_DSP_PROFILE:
 162                 return -EINVAL;
 163
 164         case SNDCTL_DSP_GETBLKSIZE:
 165                 return put_user(BUFFER_SIZE, (int *)arg);
 166
 167         case SNDCTL_DSP_SETFRAGMENT:
 168                 return 0;
 169
 170         default:
 171                 printk(KERN_ERR "sh_dac_audio: unimplemented ioctl=0x%x\n",
 172                        cmd);
 173                 return -EINVAL;
 174         }
 175         return -EINVAL;
 176 }
 177
 178 static ssize_t dac_audio_write(struct file *file, const char *buf, size_t count,
 179                                loff_t * ppos)
 180 {
 181         int free;
 182         int nbytes;
 183
 184         if (count < 0)
 185                 return -EINVAL;
 186
 187         if (!count) {
 188                 dac_audio_sync();
 189                 return 0;
 190         }
 191
 192         free = buffer_begin - buffer_end;
 193
 194         if (free < 0)
 195                 free += BUFFER_SIZE;
 196         if ((free == 0) && (empty))
 197                 free = BUFFER_SIZE;
 198         if (count > free)
 199                 count = free;
 200         if (buffer_begin > buffer_end) {
 201                 if (copy_from_user((void *)buffer_end, buf, count))
 202                         return -EFAULT;
 203
 204                 buffer_end += count;
 205         } else {
 206                 nbytes = data_buffer + BUFFER_SIZE - buffer_end;
 207                 if (nbytes > count) {
 208                         if (copy_from_user((void *)buffer_end, buf, count))
 209                                 return -EFAULT;
 210                         buffer_end += count;
 211                 } else {
 212                         if (copy_from_user((void *)buffer_end, buf, nbytes))
 213                                 return -EFAULT;
 214                         if (copy_from_user
 215                             ((void *)data_buffer, buf + nbytes, count - nbytes))
 216                                 return -EFAULT;
 217                         buffer_end = data_buffer + count - nbytes;
 218                 }
 219         }
 220
 221         if (empty) {
 222                 empty = 0;
 223                 dac_audio_start_timer();
 224         }
 225
 226         return count;
 227 }
 228
 229 static ssize_t dac_audio_read(struct file *file, char *buf, size_t count,
 230                               loff_t * ppos)
 231 {
 232         return -EINVAL;
 233 }
 234
 235 static int dac_audio_open(struct inode *inode, struct file *file)
 236 {
 237         if (file->f_mode & FMODE_READ)
 238                 return -ENODEV;
 239         if (in_use)
 240                 return -EBUSY;
 241
 242         in_use = 1;
 243
 244         dac_audio_start();
 245
 246         return 0;
 247 }
 248
 249 static int dac_audio_release(struct inode *inode, struct file *file)
 250 {
 251         dac_audio_sync();
 252         dac_audio_stop();
 253         in_use = 0;
 254
 255         return 0;
 256 }
 257
 258 const struct file_operations dac_audio_fops = {
 259       .read =           dac_audio_read,
 260       .write =  dac_audio_write,
 261       .ioctl =  dac_audio_ioctl,
 262       .open =           dac_audio_open,
 263       .release =        dac_audio_release,
 264 };
 265
 266 static irqreturn_t timer1_interrupt(int irq, void *dev)
 267 {
 268         unsigned long timer_status;
 269
 270         timer_status = ctrl_inw(TMU1_TCR);
 271         timer_status &= ~0x100;
 272         ctrl_outw(timer_status, TMU1_TCR);
 273
 274         if (!empty) {
 275                 sh_dac_output(*buffer_begin, CONFIG_SOUND_SH_DAC_AUDIO_CHANNEL);
 276                 buffer_begin++;
 277
 278                 if (buffer_begin == data_buffer + BUFFER_SIZE)
 279                         buffer_begin = data_buffer;
 280                 if (buffer_begin == buffer_end) {
 281                         empty = 1;
 282                         dac_audio_stop_timer();
 283                 }
 284         }
 285         return IRQ_HANDLED;
 286 }
 287
 288 static int __init dac_audio_init(void)
 289 {
 290         int retval;
 291
 292         if ((device_major = register_sound_dsp(&dac_audio_fops, -1)) < 0) {
 293                 printk(KERN_ERR "Cannot register dsp device");
 294                 return device_major;
 295         }
 296
 297         in_use = 0;
 298
 299         data_buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL);
 300         if (data_buffer == NULL)
 301                 return -ENOMEM;
 302
 303         dac_audio_reset();
 304         rate = 8000;
 305         dac_audio_set_rate();
 306
 307         retval =
 308             request_irq(TIMER1_IRQ, timer1_interrupt, IRQF_DISABLED, MODNAME, 0);
 309         if (retval < 0) {
 310                 printk(KERN_ERR "sh_dac_audio: IRQ %d request failed\n",
 311                        TIMER1_IRQ);
 312                 return retval;
 313         }
 314
 315         return 0;
 316 }
 317
 318 static void __exit dac_audio_exit(void)
 319 {
 320         free_irq(TIMER1_IRQ, 0);
 321
 322         unregister_sound_dsp(device_major);
 323         kfree((void *)data_buffer);
 324 }
 325
 326 module_init(dac_audio_init);
 327 module_exit(dac_audio_exit);
 328
 329 MODULE_AUTHOR("Andriy Skulysh, askulysh@image.kiev.ua");
 330 MODULE_DESCRIPTION("SH DAC sound driver");
 331 MODULE_LICENSE("GPL");