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 /* write the port and returns the next expire time in ns;
  40  * called at the trigger-start and in hrtimer callback
  41  */
  42 static u64 pcsp_timer_update(struct snd_pcsp *chip)
  43 {
  44         unsigned char timer_cnt, val;
  45         u64 ns;
  46         struct snd_pcm_substream *substream;
  47         struct snd_pcm_runtime *runtime;
  48         unsigned long flags;
  49
  50         if (chip->thalf) {
  51                 outb(chip->val61, 0x61);
  52                 chip->thalf = 0;
  53                 return chip->ns_rem;
  54         }
  55
  56         substream = chip->playback_substream;
  57         if (!substream)
  58                 return 0;
  59
  60         runtime = substream->runtime;
  61         /* assume it is mono! */
  62         val = runtime->dma_area[chip->playback_ptr + chip->fmt_size - 1];
  63         if (chip->is_signed)
  64                 val ^= 0x80;
  65         timer_cnt = val * CUR_DIV() / 256;
  66
  67         if (timer_cnt && chip->enable) {
  68                 spin_lock_irqsave(&i8253_lock, flags);
  69                 if (!nforce_wa) {
  70                         outb_p(chip->val61, 0x61);
  71                         outb_p(timer_cnt, 0x42);
  72                         outb(chip->val61 ^ 1, 0x61);
  73                 } else {
  74                         outb(chip->val61 ^ 2, 0x61);
  75                         chip->thalf = 1;
  76                 }
  77                 spin_unlock_irqrestore(&i8253_lock, flags);
  78         }
  79
  80         chip->ns_rem = PCSP_PERIOD_NS();
  81         ns = (chip->thalf ? PCSP_CALC_NS(timer_cnt) : chip->ns_rem);
  82         chip->ns_rem -= ns;
  83         return ns;
  84 }
  85
  86 static void pcsp_pointer_update(struct snd_pcsp *chip)
  87 {
  88         struct snd_pcm_substream *substream;
  89         size_t period_bytes, buffer_bytes;
  90         int periods_elapsed;
  91         unsigned long flags;
  92
  93         /* update the playback position */
  94         substream = chip->playback_substream;
  95         if (!substream)
  96                 return;
  97
  98         period_bytes = snd_pcm_lib_period_bytes(substream);
  99         buffer_bytes = snd_pcm_lib_buffer_bytes(substream);
 100
 101         spin_lock_irqsave(&chip->substream_lock, flags);
 102         chip->playback_ptr += PCSP_INDEX_INC() * chip->fmt_size;
 103         periods_elapsed = chip->playback_ptr - chip->period_ptr;
 104         if (periods_elapsed < 0) {
 105 #if PCSP_DEBUG
 106                 printk(KERN_INFO "PCSP: buffer_bytes mod period_bytes != 0 ? "
 107                         "(%zi %zi %zi)\n",
 108                         chip->playback_ptr, period_bytes, buffer_bytes);
 109 #endif
 110                 periods_elapsed += buffer_bytes;
 111         }
 112         periods_elapsed /= period_bytes;
 113         /* wrap the pointer _before_ calling snd_pcm_period_elapsed(),
 114          * or ALSA will BUG on us. */
 115         chip->playback_ptr %= buffer_bytes;
 116
 117         if (periods_elapsed) {
 118                 chip->period_ptr += periods_elapsed * period_bytes;
 119                 chip->period_ptr %= buffer_bytes;
 120         }
 121         spin_unlock_irqrestore(&chip->substream_lock, flags);
 122
 123         if (periods_elapsed)
 124                 tasklet_schedule(&pcsp_pcm_tasklet);
 125 }
 126
 127 enum hrtimer_restart pcsp_do_timer(struct hrtimer *handle)
 128 {
 129         struct snd_pcsp *chip = container_of(handle, struct snd_pcsp, timer);
 130         int pointer_update;
 131         u64 ns;
 132
 133         if (!atomic_read(&chip->timer_active) || !chip->playback_substream)
 134                 return HRTIMER_NORESTART;
 135
 136         pointer_update = !chip->thalf;
 137         ns = pcsp_timer_update(chip);
 138         if (!ns) {
 139                 printk(KERN_WARNING "PCSP: unexpected stop\n");
 140                 return HRTIMER_NORESTART;
 141         }
 142
 143         if (pointer_update)
 144                 pcsp_pointer_update(chip);
 145
 146         hrtimer_forward(handle, hrtimer_get_expires(handle), ns_to_ktime(ns));
 147
 148         return HRTIMER_RESTART;
 149 }
 150
 151 static int pcsp_start_playing(struct snd_pcsp *chip)
 152 {
 153 #if PCSP_DEBUG
 154         printk(KERN_INFO "PCSP: start_playing called\n");
 155 #endif
 156         if (atomic_read(&chip->timer_active)) {
 157                 printk(KERN_ERR "PCSP: Timer already active\n");
 158                 return -EIO;
 159         }
 160
 161         spin_lock(&i8253_lock);
 162         chip->val61 = inb(0x61) | 0x03;
 163         outb_p(0x92, 0x43);     /* binary, mode 1, LSB only, ch 2 */
 164         spin_unlock(&i8253_lock);
 165         atomic_set(&chip->timer_active, 1);
 166         chip->thalf = 0;
 167
 168         hrtimer_start(&pcsp_chip.timer, ktime_set(0, 0), HRTIMER_MODE_REL);
 169         return 0;
 170 }
 171
 172 static void pcsp_stop_playing(struct snd_pcsp *chip)
 173 {
 174 #if PCSP_DEBUG
 175         printk(KERN_INFO "PCSP: stop_playing called\n");
 176 #endif
 177         if (!atomic_read(&chip->timer_active))
 178                 return;
 179
 180         atomic_set(&chip->timer_active, 0);
 181         spin_lock(&i8253_lock);
 182         /* restore the timer */
 183         outb_p(0xb6, 0x43);     /* binary, mode 3, LSB/MSB, ch 2 */
 184         outb(chip->val61 & 0xFC, 0x61);
 185         spin_unlock(&i8253_lock);
 186 }
 187
 188 /*
 189  * Force to stop and sync the stream
 190  */
 191 void pcsp_sync_stop(struct snd_pcsp *chip)
 192 {
 193         local_irq_disable();
 194         pcsp_stop_playing(chip);
 195         local_irq_enable();
 196         hrtimer_cancel(&chip->timer);
 197         tasklet_kill(&pcsp_pcm_tasklet);
 198 }
 199
 200 static int snd_pcsp_playback_close(struct snd_pcm_substream *substream)
 201 {
 202         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 203 #if PCSP_DEBUG
 204         printk(KERN_INFO "PCSP: close called\n");
 205 #endif
 206         pcsp_sync_stop(chip);
 207         chip->playback_substream = NULL;
 208         return 0;
 209 }
 210
 211 static int snd_pcsp_playback_hw_params(struct snd_pcm_substream *substream,
 212                                        struct snd_pcm_hw_params *hw_params)
 213 {
 214         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 215         int err;
 216         pcsp_sync_stop(chip);
 217         err = snd_pcm_lib_malloc_pages(substream,
 218                                       params_buffer_bytes(hw_params));
 219         if (err < 0)
 220                 return err;
 221         return 0;
 222 }
 223
 224 static int snd_pcsp_playback_hw_free(struct snd_pcm_substream *substream)
 225 {
 226         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 227 #if PCSP_DEBUG
 228         printk(KERN_INFO "PCSP: hw_free called\n");
 229 #endif
 230         pcsp_sync_stop(chip);
 231         return snd_pcm_lib_free_pages(substream);
 232 }
 233
 234 static int snd_pcsp_playback_prepare(struct snd_pcm_substream *substream)
 235 {
 236         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 237         pcsp_sync_stop(chip);
 238         chip->playback_ptr = 0;
 239         chip->period_ptr = 0;
 240         chip->fmt_size =
 241                 snd_pcm_format_physical_width(substream->runtime->format) >> 3;
 242         chip->is_signed = snd_pcm_format_signed(substream->runtime->format);
 243 #if PCSP_DEBUG
 244         printk(KERN_INFO "PCSP: prepare called, "
 245                         "size=%zi psize=%zi f=%zi f1=%i fsize=%i\n",
 246                         snd_pcm_lib_buffer_bytes(substream),
 247                         snd_pcm_lib_period_bytes(substream),
 248                         snd_pcm_lib_buffer_bytes(substream) /
 249                         snd_pcm_lib_period_bytes(substream),
 250                         substream->runtime->periods,
 251                         chip->fmt_size);
 252 #endif
 253         return 0;
 254 }
 255
 256 static int snd_pcsp_trigger(struct snd_pcm_substream *substream, int cmd)
 257 {
 258         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 259 #if PCSP_DEBUG
 260         printk(KERN_INFO "PCSP: trigger called\n");
 261 #endif
 262         switch (cmd) {
 263         case SNDRV_PCM_TRIGGER_START:
 264         case SNDRV_PCM_TRIGGER_RESUME:
 265                 return pcsp_start_playing(chip);
 266         case SNDRV_PCM_TRIGGER_STOP:
 267         case SNDRV_PCM_TRIGGER_SUSPEND:
 268                 pcsp_stop_playing(chip);
 269                 break;
 270         default:
 271                 return -EINVAL;
 272         }
 273         return 0;
 274 }
 275
 276 static snd_pcm_uframes_t snd_pcsp_playback_pointer(struct snd_pcm_substream
 277                                                    *substream)
 278 {
 279         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 280         unsigned int pos;
 281         spin_lock(&chip->substream_lock);
 282         pos = chip->playback_ptr;
 283         spin_unlock(&chip->substream_lock);
 284         return bytes_to_frames(substream->runtime, pos);
 285 }
 286
 287 static struct snd_pcm_hardware snd_pcsp_playback = {
 288         .info = (SNDRV_PCM_INFO_INTERLEAVED |
 289                  SNDRV_PCM_INFO_HALF_DUPLEX |
 290                  SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID),
 291         .formats = (SNDRV_PCM_FMTBIT_U8
 292 #if DMIX_WANTS_S16
 293                     | SNDRV_PCM_FMTBIT_S16_LE
 294 #endif
 295             ),
 296         .rates = SNDRV_PCM_RATE_KNOT,
 297         .rate_min = PCSP_DEFAULT_SRATE,
 298         .rate_max = PCSP_DEFAULT_SRATE,
 299         .channels_min = 1,
 300         .channels_max = 1,
 301         .buffer_bytes_max = PCSP_BUFFER_SIZE,
 302         .period_bytes_min = 64,
 303         .period_bytes_max = PCSP_MAX_PERIOD_SIZE,
 304         .periods_min = 2,
 305         .periods_max = PCSP_MAX_PERIODS,
 306         .fifo_size = 0,
 307 };
 308
 309 static int snd_pcsp_playback_open(struct snd_pcm_substream *substream)
 310 {
 311         struct snd_pcsp *chip = snd_pcm_substream_chip(substream);
 312         struct snd_pcm_runtime *runtime = substream->runtime;
 313 #if PCSP_DEBUG
 314         printk(KERN_INFO "PCSP: open called\n");
 315 #endif
 316         if (atomic_read(&chip->timer_active)) {
 317                 printk(KERN_ERR "PCSP: still active!!\n");
 318                 return -EBUSY;
 319         }
 320         runtime->hw = snd_pcsp_playback;
 321         chip->playback_substream = substream;
 322         return 0;
 323 }
 324
 325 static struct snd_pcm_ops snd_pcsp_playback_ops = {
 326         .open = snd_pcsp_playback_open,
 327         .close = snd_pcsp_playback_close,
 328         .ioctl = snd_pcm_lib_ioctl,
 329         .hw_params = snd_pcsp_playback_hw_params,
 330         .hw_free = snd_pcsp_playback_hw_free,
 331         .prepare = snd_pcsp_playback_prepare,
 332         .trigger = snd_pcsp_trigger,
 333         .pointer = snd_pcsp_playback_pointer,
 334 };
 335
 336 int __devinit snd_pcsp_new_pcm(struct snd_pcsp *chip)
 337 {
 338         int err;
 339
 340         err = snd_pcm_new(chip->card, "pcspeaker", 0, 1, 0, &chip->pcm);
 341         if (err < 0)
 342                 return err;
 343
 344         snd_pcm_set_ops(chip->pcm, SNDRV_PCM_STREAM_PLAYBACK,
 345                         &snd_pcsp_playback_ops);
 346
 347         chip->pcm->private_data = chip;
 348         chip->pcm->info_flags = SNDRV_PCM_INFO_HALF_DUPLEX;
 349         strcpy(chip->pcm->name, "pcsp");
 350
 351         snd_pcm_lib_preallocate_pages_for_all(chip->pcm,
 352                                               SNDRV_DMA_TYPE_CONTINUOUS,
 353                                               snd_dma_continuous_data
 354                                               (GFP_KERNEL), PCSP_BUFFER_SIZE,
 355                                               PCSP_BUFFER_SIZE);
 356
 357         return 0;
 358 }