sound/drivers/pcsp/pcsp_lib.c

   1 /*
   2  * PC-Speaker driver for Linux
   3  *
   4  * Copyright (C) 1993-1997  Michael Beck
   5  * Copyright (C) 1997-2001  David Woodhouse
   6  * Copyright (C) 2001-2008  Stas Sergeev
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/moduleparam.h>
  11 #include <linux/interrupt.h>
  12 #include <sound/pcm.h>
  13 #include <asm/io.h>
  14 #include "pcsp.h"
  15
  16 static int nforce_wa;
  17 module_param(nforce_wa, bool, 0444);
  18 MODULE_PARM_DESC(nforce_wa, "Apply NForce chipset workaround "
  19                 "(expect bad sound)");
  20
  21 #define DMIX_WANTS_S16  1
  22
  23 /*
  24  * Call snd_pcm_period_elapsed in a tasklet
  25  * This avoids spinlock messes and long-running irq contexts
  26  */
  27 static void pcsp_call_pcm_elapsed(unsigned long priv)
  28 {
  29         if (atomic_read(&pcsp_chip.timer_active)) {
  30                 struct snd_pcm_substream *substream;
  31                 substream = pcsp_chip.playback_substream;
  32                 if (substream)
  33                         snd_pcm_period_elapsed(substream);
  34         }
  35 }
  36
  37 static DECLARE_TASKLET(pcsp_pcm_tasklet, pcsp_call_pcm_elapsed, 0);
  38
  39 enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle)
  40 {
  41         unsigned char timer_cnt, val;
  42         int fmt_size, periods_elapsed;
  43         u64 ns;
  44         size_t period_bytes, buffer_bytes;
  45         struct snd_pcm_substream *substream;
  46         struct snd_pcm_runtime *runtime;
  47         struct snd_pcsp *chip = container_of(handle, struct snd_pcsp, timer);
  48         unsigned long flags;
  49
  50         if (chip->thalf) {
  51                 outb(chip->val61, 0x61);
  52                 chip->thalf = 0;
  53                 if (!atomic_read(&chip->timer_active))
  54                         goto stop;
  55                 hrtimer_forward(&chip->timer, chip->timer.expires,
  56                                 ktime_set(0, chip->ns_rem));
  57                 return HRTIMER_RESTART;
  58         }
  59
  60         if (!atomic_read(&chip->timer_active))
  61                 goto stop;
  62         substream = chip->playback_substream;
  63         if (!substream)
  64                 goto stop;
  65
  66         runtime = substream->runtime;
  67         fmt_size = snd_pcm_format_physical_width(runtime->format) >> 3;
  68         /* assume it is mono! */
  69         val = runtime->dma_area[chip->playback_ptr + fmt_size - 1];
  70         if (snd_pcm_format_signed(runtime->format))
  71                 val ^= 0x80;
  72         timer_cnt = val * CUR_DIV() / 256;
  73
  74         if (timer_cnt && chip->enable) {
  75                 spin_lock(&i8253_lock);
  76                 if (!nforce_wa) {
  77                         outb_p(chip->val61, 0x61);
  78                         outb_p(timer_cnt, 0x42);
  79                         outb(chip->val61 ^ 1, 0x61);
  80                 } else {
  81                         outb(chip->val61 ^ 2, 0x61);
  82                         chip->thalf = 1;
  83                 }
  84                 spin_unlock(&i8253_lock);
  85         }
  86
  87         period_bytes = snd_pcm_lib_period_bytes(substream);
  88         buffer_bytes = snd_pcm_lib_buffer_bytes(substream);
  89
  90         spin_lock_irqsave(&chip->substream_lock, flags);
  91         chip->playback_ptr += PCSP_INDEX_INC() * fmt_size;
  92         periods_elapsed = chip->playback_ptr - chip->period_ptr;
  93         if (periods_elapsed < 0) {
  94 #if PCSP_DEBUG
  95                 printk(KERN_INFO "PCSP: buffer_bytes mod period_bytes != 0 ? "
  96                         "(%zi %zi %zi)\n",
  97                         chip->playback_ptr, period_bytes, buffer_bytes);
  98 #endif
  99                 periods_elapsed += buffer_bytes;
 100         }
 101         periods_elapsed /= period_bytes;
 102         /* wrap the pointer _before_ calling snd_pcm_period_elapsed(),
 103          * or ALSA will BUG on us. */
 104         chip->playback_ptr %= buffer_bytes;
 105
 106         if (periods_elapsed) {
 107                 chip->period_ptr += periods_elapsed * period_bytes;
 108                 chip->period_ptr %= buffer_bytes;
 109                 tasklet_schedule(&pcsp_pcm_tasklet);
 110         }
 111         spin_unlock_irqrestore(&chip->substream_lock, flags);
 112
 113         if (!atomic_read(&chip->timer_active))
 114                 goto stop;
 115
 116         chip->ns_rem = PCSP_PERIOD_NS();
 117         ns = (chip->thalf ? PCSP_CALC_NS(timer_cnt) : chip->ns_rem);
 118         chip->ns_rem -= ns;
 119         hrtimer_forward(&chip->timer, chip->timer.expires, ktime_set(0, ns));
 120         return HRTIMER_RESTART;
 121
 122  stop:
 123         return HRTIMER_NORESTART;
 124 }
 125
 126 static void pcsp_start_playing(struct snd_pcsp *chip)
 127 {
 128 #if PCSP_DEBUG
 129         printk(KERN_INFO "PCSP: start_playing called\n");
 130 #endif
 131         if (atomic_read(&chip->timer_active)) {
 132                 printk(KERN_ERR "PCSP: Timer already active\n");
 133                 return;
 134         }
 135
 136         spin_lock(&i8253_lock);
 137         chip->val61 = inb(0x61) | 0x03;
 138         outb_p(0x92, 0x43);     /* binary, mode 1, LSB only, ch 2 */
 139         spin_unlock(&i8253_lock);
 140         atomic_set(&chip->timer_active, 1);
 141         chip->thalf = 0;
 142
 143         hrtimer_start(&pcsp_chip.timer, ktime_set(0, 0), HRTIMER_MODE_REL);
 144 }
 145
 146 static void pcsp_stop_playing(struct snd_pcsp *chip)
 147 {
 148 #if PCSP_DEBUG
 149         printk(KERN_INFO "PCSP: stop_playing called\n");
 150 #endif
 151         if (!atomic_read(&chip->timer_active))
 152                 return;
 153
 154         atomic_set(&chip->timer_active, 0);
 155         spin_lock(&i8253_lock);
 156         /* restore the timer */
 157         outb_p(0xb6, 0x43);     /* binary, mode 3, LSB/MSB, ch 2 */
 158         outb(chip->val61 & 0xFC, 0x61);
 159         spin_unlock(&i8253_lock);
 160 }
 161
 162 /*
 163  * Force to stop and sync the stream
 164  */
 165 void pcsp_sync_stop(struct snd_pcsp *chip)
 166 {
 167         local_irq_disable();
 168         pcsp_stop_playing(chip);
 169         local_irq_enable();
 170         hrtimer_cancel(&chip->timer);
 171         tasklet_kill(&pcsp_pcm_tasklet);
 172 }
 173
 174 static int snd_pcsp_playback_close(struct snd_pcm_substream *substream)
 175 {
 176         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 177 #if PCSP_DEBUG
 178         printk(KERN_INFO "PCSP: close called\n");
 179 #endif
 180         pcsp_sync_stop(chip);
 181         chip->playback_substream = NULL;
 182         return 0;
 183 }
 184
 185 static int snd_pcsp_playback_hw_params(struct snd_pcm_substream *substream,
 186                                        struct snd_pcm_hw_params *hw_params)
 187 {
 188         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 189         int err;
 190         pcsp_sync_stop(chip);
 191         err = snd_pcm_lib_malloc_pages(substream,
 192                                       params_buffer_bytes(hw_params));
 193         if (err < 0)
 194                 return err;
 195         return 0;
 196 }
 197
 198 static int snd_pcsp_playback_hw_free(struct snd_pcm_substream *substream)
 199 {
 200         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 201 #if PCSP_DEBUG
 202         printk(KERN_INFO "PCSP: hw_free called\n");
 203 #endif
 204         pcsp_sync_stop(chip);
 205         return snd_pcm_lib_free_pages(substream);
 206 }
 207
 208 static int snd_pcsp_playback_prepare(struct snd_pcm_substream *substream)
 209 {
 210         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 211 #if PCSP_DEBUG
 212         printk(KERN_INFO "PCSP: prepare called, "
 213                         "size=%zi psize=%zi f=%zi f1=%i\n",
 214                         snd_pcm_lib_buffer_bytes(substream),
 215                         snd_pcm_lib_period_bytes(substream),
 216                         snd_pcm_lib_buffer_bytes(substream) /
 217                         snd_pcm_lib_period_bytes(substream),
 218                         substream->runtime->periods);
 219 #endif
 220         pcsp_sync_stop(chip);
 221         chip->playback_ptr = 0;
 222         chip->period_ptr = 0;
 223         return 0;
 224 }
 225
 226 static int snd_pcsp_trigger(struct snd_pcm_substream *substream, int cmd)
 227 {
 228         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 229 #if PCSP_DEBUG
 230         printk(KERN_INFO "PCSP: trigger called\n");
 231 #endif
 232         switch (cmd) {
 233         case SNDRV_PCM_TRIGGER_START:
 234         case SNDRV_PCM_TRIGGER_RESUME:
 235                 pcsp_start_playing(chip);
 236                 break;
 237         case SNDRV_PCM_TRIGGER_STOP:
 238         case SNDRV_PCM_TRIGGER_SUSPEND:
 239                 pcsp_stop_playing(chip);
 240                 break;
 241         default:
 242                 return -EINVAL;
 243         }
 244         return 0;
 245 }
 246
 247 static snd_pcm_uframes_t snd_pcsp_playback_pointer(struct snd_pcm_substream
 248                                                    *substream)
 249 {
 250         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 251         unsigned int pos;
 252         spin_lock(&chip->substream_lock);
 253         pos = chip->playback_ptr;
 254         spin_unlock(&chip->substream_lock);
 255         return bytes_to_frames(substream->runtime, pos);
 256 }
 257
 258 static struct snd_pcm_hardware snd_pcsp_playback = {
 259         .info = (SNDRV_PCM_INFO_INTERLEAVED |
 260                  SNDRV_PCM_INFO_HALF_DUPLEX |
 261                  SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID),
 262         .formats = (SNDRV_PCM_FMTBIT_U8
 263 #if DMIX_WANTS_S16
 264                     | SNDRV_PCM_FMTBIT_S16_LE
 265 #endif
 266             ),
 267         .rates = SNDRV_PCM_RATE_KNOT,
 268         .rate_min = PCSP_DEFAULT_SRATE,
 269         .rate_max = PCSP_DEFAULT_SRATE,
 270         .channels_min = 1,
 271         .channels_max = 1,
 272         .buffer_bytes_max = PCSP_BUFFER_SIZE,
 273         .period_bytes_min = 64,
 274         .period_bytes_max = PCSP_MAX_PERIOD_SIZE,
 275         .periods_min = 2,
 276         .periods_max = PCSP_MAX_PERIODS,
 277         .fifo_size = 0,
 278 };
 279
 280 static int snd_pcsp_playback_open(struct snd_pcm_substream *substream)
 281 {
 282         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 283         struct snd_pcm_runtime *runtime = substream->runtime;
 284 #if PCSP_DEBUG
 285         printk(KERN_INFO "PCSP: open called\n");
 286 #endif
 287         if (atomic_read(&chip->timer_active)) {
 288                 printk(KERN_ERR "PCSP: still active!!\n");
 289                 return -EBUSY;
 290         }
 291         runtime->hw = snd_pcsp_playback;
 292         chip->playback_substream = substream;
 293         return 0;
 294 }
 295
 296 static struct snd_pcm_ops snd_pcsp_playback_ops = {
 297         .open = snd_pcsp_playback_open,
 298         .close = snd_pcsp_playback_close,
 299         .ioctl = snd_pcm_lib_ioctl,
 300         .hw_params = snd_pcsp_playback_hw_params,
 301         .hw_free = snd_pcsp_playback_hw_free,
 302         .prepare = snd_pcsp_playback_prepare,
 303         .trigger = snd_pcsp_trigger,
 304         .pointer = snd_pcsp_playback_pointer,
 305 };
 306
 307 int __devinit snd_pcsp_new_pcm(struct snd_pcsp *chip)
 308 {
 309         int err;
 310
 311         err = snd_pcm_new(chip->card, "pcspeaker", 0, 1, 0, &chip->pcm);
 312         if (err < 0)
 313                 return err;
 314
 315         snd_pcm_set_ops(chip->pcm, SNDRV_PCM_STREAM_PLAYBACK,
 316                         &snd_pcsp_playback_ops);
 317
 318         chip->pcm->private_data = chip;
 319         chip->pcm->info_flags = SNDRV_PCM_INFO_HALF_DUPLEX;
 320         strcpy(chip->pcm->name, "pcsp");
 321
 322         snd_pcm_lib_preallocate_pages_for_all(chip->pcm,
 323                                               SNDRV_DMA_TYPE_CONTINUOUS,
 324                                               snd_dma_continuous_data
 325                                               (GFP_KERNEL), PCSP_BUFFER_SIZE,
 326                                               PCSP_BUFFER_SIZE);
 327
 328         return 0;
 329 }