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