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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /sound/oss/emu10k1/cardwo.c
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'sound/oss/emu10k1/cardwo.c')
-rw-r--r--sound/oss/emu10k1/cardwo.c643
1 files changed, 643 insertions, 0 deletions
diff --git a/sound/oss/emu10k1/cardwo.c b/sound/oss/emu10k1/cardwo.c
new file mode 100644
index 00000000000..54daca4f57b
--- /dev/null
+++ b/sound/oss/emu10k1/cardwo.c
@@ -0,0 +1,643 @@
+/*
+ **********************************************************************
+ * cardwo.c - PCM output HAL for emu10k1 driver
+ * Copyright 1999, 2000 Creative Labs, Inc.
+ *
+ **********************************************************************
+ *
+ * Date Author Summary of changes
+ * ---- ------ ------------------
+ * October 20, 1999 Bertrand Lee base code release
+ *
+ **********************************************************************
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
+ * USA.
+ *
+ **********************************************************************
+ */
+
+#include <linux/poll.h>
+#include "hwaccess.h"
+#include "8010.h"
+#include "voicemgr.h"
+#include "cardwo.h"
+#include "audio.h"
+
+static u32 samplerate_to_linearpitch(u32 samplingrate)
+{
+ samplingrate = (samplingrate << 8) / 375;
+ return (samplingrate >> 1) + (samplingrate & 1);
+}
+
+static void query_format(struct emu10k1_wavedevice *wave_dev, struct wave_format *wave_fmt)
+{
+ int i, j, do_passthrough = 0, is_ac3 = 0;
+ struct emu10k1_card *card = wave_dev->card;
+ struct woinst *woinst = wave_dev->woinst;
+
+ if ((wave_fmt->channels > 2) && (wave_fmt->id != AFMT_S16_LE) && (wave_fmt->id != AFMT_U8))
+ wave_fmt->channels = 2;
+
+ if ((wave_fmt->channels < 1) || (wave_fmt->channels > WAVEOUT_MAXVOICES))
+ wave_fmt->channels = 2;
+
+ if (wave_fmt->channels == 2)
+ woinst->num_voices = 1;
+ else
+ woinst->num_voices = wave_fmt->channels;
+
+ if (wave_fmt->samplingrate >= 0x2ee00)
+ wave_fmt->samplingrate = 0x2ee00;
+
+ wave_fmt->passthrough = 0;
+ do_passthrough = is_ac3 = 0;
+
+ if (card->pt.selected)
+ do_passthrough = 1;
+
+ switch (wave_fmt->id) {
+ case AFMT_S16_LE:
+ wave_fmt->bitsperchannel = 16;
+ break;
+ case AFMT_U8:
+ wave_fmt->bitsperchannel = 8;
+ break;
+ case AFMT_AC3:
+ do_passthrough = 1;
+ is_ac3 = 1;
+ break;
+ default:
+ wave_fmt->id = AFMT_S16_LE;
+ wave_fmt->bitsperchannel = 16;
+ break;
+ }
+ if (do_passthrough) {
+ /* currently only one waveout instance may use pass-through */
+ if (woinst->state != WAVE_STATE_CLOSED ||
+ card->pt.state != PT_STATE_INACTIVE ||
+ (wave_fmt->samplingrate != 48000 && !is_ac3)) {
+ DPF(2, "unable to set pass-through mode\n");
+ } else if (USE_PT_METHOD1) {
+ i = emu10k1_find_control_gpr(&card->mgr, card->pt.patch_name, card->pt.intr_gpr_name);
+ j = emu10k1_find_control_gpr(&card->mgr, card->pt.patch_name, card->pt.enable_gpr_name);
+ if (i < 0 || j < 0)
+ DPF(2, "unable to set pass-through mode\n");
+ else {
+ wave_fmt->samplingrate = 48000;
+ wave_fmt->channels = 2;
+ card->pt.pos_gpr = emu10k1_find_control_gpr(&card->mgr, card->pt.patch_name,
+ card->pt.pos_gpr_name);
+ wave_fmt->passthrough = 1;
+ card->pt.intr_gpr = i;
+ card->pt.enable_gpr = j;
+ card->pt.state = PT_STATE_INACTIVE;
+
+ DPD(2, "is_ac3 is %d\n", is_ac3);
+ card->pt.ac3data = is_ac3;
+ wave_fmt->bitsperchannel = 16;
+ }
+ }else{
+ DPF(2, "Using Passthrough Method 2\n");
+ card->pt.enable_gpr = emu10k1_find_control_gpr(&card->mgr, card->pt.patch_name,
+ card->pt.enable_gpr_name);
+ wave_fmt->passthrough = 2;
+ wave_fmt->bitsperchannel = 16;
+ }
+ }
+
+ wave_fmt->bytesperchannel = wave_fmt->bitsperchannel >> 3;
+ wave_fmt->bytespersample = wave_fmt->channels * wave_fmt->bytesperchannel;
+ wave_fmt->bytespersec = wave_fmt->bytespersample * wave_fmt->samplingrate;
+
+ if (wave_fmt->channels == 2)
+ wave_fmt->bytespervoicesample = wave_fmt->channels * wave_fmt->bytesperchannel;
+ else
+ wave_fmt->bytespervoicesample = wave_fmt->bytesperchannel;
+}
+
+static int get_voice(struct emu10k1_card *card, struct woinst *woinst, unsigned int voicenum)
+{
+ struct emu_voice *voice = &woinst->voice[voicenum];
+
+ /* Allocate voices here, if no voices available, return error. */
+
+ voice->usage = VOICE_USAGE_PLAYBACK;
+
+ voice->flags = 0;
+
+ if (woinst->format.channels == 2)
+ voice->flags |= VOICE_FLAGS_STEREO;
+
+ if (woinst->format.bitsperchannel == 16)
+ voice->flags |= VOICE_FLAGS_16BIT;
+
+ if (emu10k1_voice_alloc(card, voice) < 0) {
+ voice->usage = VOICE_USAGE_FREE;
+ return -1;
+ }
+
+ /* Calculate pitch */
+ voice->initial_pitch = (u16) (srToPitch(woinst->format.samplingrate) >> 8);
+ voice->pitch_target = samplerate_to_linearpitch(woinst->format.samplingrate);
+
+ DPD(2, "Initial pitch --> %#x\n", voice->initial_pitch);
+
+ voice->startloop = (voice->mem.emupageindex << 12) /
+ woinst->format.bytespervoicesample;
+ voice->endloop = voice->startloop + woinst->buffer.size / woinst->format.bytespervoicesample;
+ voice->start = voice->startloop;
+
+
+ voice->params[0].volume_target = 0xffff;
+ voice->params[0].initial_fc = 0xff;
+ voice->params[0].initial_attn = 0x00;
+ voice->params[0].byampl_env_sustain = 0x7f;
+ voice->params[0].byampl_env_decay = 0x7f;
+
+
+ if (voice->flags & VOICE_FLAGS_STEREO) {
+ if (woinst->format.passthrough == 2) {
+ voice->params[0].send_routing = voice->params[1].send_routing = card->waveout.send_routing[ROUTE_PT];
+ voice->params[0].send_routing2 = voice->params[1].send_routing2 = card->waveout.send_routing2[ROUTE_PT];
+ voice->params[0].send_dcba = 0xff;
+ voice->params[1].send_dcba = 0xff00;
+ voice->params[0].send_hgfe = voice->params[1].send_hgfe=0;
+ } else {
+ voice->params[0].send_dcba = card->waveout.send_dcba[SEND_LEFT];
+ voice->params[0].send_hgfe = card->waveout.send_hgfe[SEND_LEFT];
+ voice->params[1].send_dcba = card->waveout.send_dcba[SEND_RIGHT];
+ voice->params[1].send_hgfe = card->waveout.send_hgfe[SEND_RIGHT];
+
+ if (woinst->device) {
+ // /dev/dps1
+ voice->params[0].send_routing = voice->params[1].send_routing = card->waveout.send_routing[ROUTE_PCM1];
+ voice->params[0].send_routing2 = voice->params[1].send_routing2 = card->waveout.send_routing2[ROUTE_PCM1];
+ } else {
+ voice->params[0].send_routing = voice->params[1].send_routing = card->waveout.send_routing[ROUTE_PCM];
+ voice->params[0].send_routing2 = voice->params[1].send_routing2 = card->waveout.send_routing2[ROUTE_PCM];
+ }
+ }
+
+ voice->params[1].volume_target = 0xffff;
+ voice->params[1].initial_fc = 0xff;
+ voice->params[1].initial_attn = 0x00;
+ voice->params[1].byampl_env_sustain = 0x7f;
+ voice->params[1].byampl_env_decay = 0x7f;
+ } else {
+ if (woinst->num_voices > 1) {
+ // Multichannel pcm
+ voice->params[0].send_dcba=0xff;
+ voice->params[0].send_hgfe=0;
+ if (card->is_audigy) {
+ voice->params[0].send_routing = 0x3f3f3f00 + card->mchannel_fx + voicenum;
+ voice->params[0].send_routing2 = 0x3f3f3f3f;
+ } else {
+ voice->params[0].send_routing = 0xfff0 + card->mchannel_fx + voicenum;
+ }
+
+ } else {
+ voice->params[0].send_dcba = card->waveout.send_dcba[SEND_MONO];
+ voice->params[0].send_hgfe = card->waveout.send_hgfe[SEND_MONO];
+
+ if (woinst->device) {
+ voice->params[0].send_routing = card->waveout.send_routing[ROUTE_PCM1];
+ voice->params[0].send_routing2 = card->waveout.send_routing2[ROUTE_PCM1];
+ } else {
+ voice->params[0].send_routing = card->waveout.send_routing[ROUTE_PCM];
+ voice->params[0].send_routing2 = card->waveout.send_routing2[ROUTE_PCM];
+ }
+ }
+ }
+
+ DPD(2, "voice: startloop=%#x, endloop=%#x\n", voice->startloop, voice->endloop);
+
+ emu10k1_voice_playback_setup(voice);
+
+ return 0;
+}
+
+int emu10k1_waveout_open(struct emu10k1_wavedevice *wave_dev)
+{
+ struct emu10k1_card *card = wave_dev->card;
+ struct woinst *woinst = wave_dev->woinst;
+ struct waveout_buffer *buffer = &woinst->buffer;
+ unsigned int voicenum;
+ u16 delay;
+
+ DPF(2, "emu10k1_waveout_open()\n");
+
+ for (voicenum = 0; voicenum < woinst->num_voices; voicenum++) {
+ if (emu10k1_voice_alloc_buffer(card, &woinst->voice[voicenum].mem, woinst->buffer.pages) < 0) {
+ ERROR();
+ emu10k1_waveout_close(wave_dev);
+ return -1;
+ }
+
+ if (get_voice(card, woinst, voicenum) < 0) {
+ ERROR();
+ emu10k1_waveout_close(wave_dev);
+ return -1;
+ }
+ }
+
+ buffer->fill_silence = 0;
+ buffer->silence_bytes = 0;
+ buffer->silence_pos = 0;
+ buffer->hw_pos = 0;
+ buffer->free_bytes = woinst->buffer.size;
+
+ delay = (48000 * woinst->buffer.fragment_size) /
+ (woinst->format.samplingrate * woinst->format.bytespervoicesample);
+
+ emu10k1_timer_install(card, &woinst->timer, delay);
+
+ woinst->state = WAVE_STATE_OPEN;
+
+ return 0;
+}
+
+void emu10k1_waveout_close(struct emu10k1_wavedevice *wave_dev)
+{
+ struct emu10k1_card *card = wave_dev->card;
+ struct woinst *woinst = wave_dev->woinst;
+ unsigned int voicenum;
+
+ DPF(2, "emu10k1_waveout_close()\n");
+
+ emu10k1_waveout_stop(wave_dev);
+
+ emu10k1_timer_uninstall(card, &woinst->timer);
+
+ for (voicenum = 0; voicenum < woinst->num_voices; voicenum++) {
+ emu10k1_voice_free(&woinst->voice[voicenum]);
+ emu10k1_voice_free_buffer(card, &woinst->voice[voicenum].mem);
+ }
+
+ woinst->state = WAVE_STATE_CLOSED;
+}
+
+void emu10k1_waveout_start(struct emu10k1_wavedevice *wave_dev)
+{
+ struct emu10k1_card *card = wave_dev->card;
+ struct woinst *woinst = wave_dev->woinst;
+ struct pt_data *pt = &card->pt;
+
+ DPF(2, "emu10k1_waveout_start()\n");
+
+ if (woinst->format.passthrough == 2) {
+ emu10k1_pt_setup(wave_dev);
+ sblive_writeptr(card, (card->is_audigy ? A_GPR_BASE : GPR_BASE) + pt->enable_gpr, 0, 1);
+ pt->state = PT_STATE_PLAYING;
+ }
+
+ /* Actual start */
+ emu10k1_voices_start(woinst->voice, woinst->num_voices, woinst->total_played);
+
+ emu10k1_timer_enable(card, &woinst->timer);
+
+ woinst->state |= WAVE_STATE_STARTED;
+}
+
+int emu10k1_waveout_setformat(struct emu10k1_wavedevice *wave_dev, struct wave_format *format)
+{
+ struct emu10k1_card *card = wave_dev->card;
+ struct woinst *woinst = wave_dev->woinst;
+ unsigned int voicenum;
+ u16 delay;
+
+ DPF(2, "emu10k1_waveout_setformat()\n");
+
+ if (woinst->state & WAVE_STATE_STARTED)
+ return -1;
+
+ query_format(wave_dev, format);
+
+ if (woinst->format.samplingrate != format->samplingrate ||
+ woinst->format.channels != format->channels ||
+ woinst->format.bitsperchannel != format->bitsperchannel) {
+
+ woinst->format = *format;
+
+ if (woinst->state == WAVE_STATE_CLOSED)
+ return 0;
+
+ emu10k1_timer_uninstall(card, &woinst->timer);
+
+ for (voicenum = 0; voicenum < woinst->num_voices; voicenum++) {
+ emu10k1_voice_free(&woinst->voice[voicenum]);
+
+ if (get_voice(card, woinst, voicenum) < 0) {
+ ERROR();
+ emu10k1_waveout_close(wave_dev);
+ return -1;
+ }
+ }
+
+ delay = (48000 * woinst->buffer.fragment_size) /
+ (woinst->format.samplingrate * woinst->format.bytespervoicesample);
+
+ emu10k1_timer_install(card, &woinst->timer, delay);
+ }
+
+ return 0;
+}
+
+void emu10k1_waveout_stop(struct emu10k1_wavedevice *wave_dev)
+{
+ struct emu10k1_card *card = wave_dev->card;
+ struct woinst *woinst = wave_dev->woinst;
+
+ DPF(2, "emu10k1_waveout_stop()\n");
+
+ if (!(woinst->state & WAVE_STATE_STARTED))
+ return;
+
+ emu10k1_timer_disable(card, &woinst->timer);
+
+ /* Stop actual voices */
+ emu10k1_voices_stop(woinst->voice, woinst->num_voices);
+
+ emu10k1_waveout_update(woinst);
+
+ woinst->state &= ~WAVE_STATE_STARTED;
+}
+
+/**
+ * emu10k1_waveout_getxfersize -
+ *
+ * gives the total free bytes on the voice buffer, including silence bytes
+ * (basically: total_free_bytes = free_bytes + silence_bytes).
+ *
+ */
+void emu10k1_waveout_getxfersize(struct woinst *woinst, u32 *total_free_bytes)
+{
+ struct waveout_buffer *buffer = &woinst->buffer;
+ int pending_bytes;
+
+ if (woinst->mmapped) {
+ *total_free_bytes = buffer->free_bytes;
+ return;
+ }
+
+ pending_bytes = buffer->size - buffer->free_bytes;
+
+ buffer->fill_silence = (pending_bytes < (signed) buffer->fragment_size * 2) ? 1 : 0;
+
+ if (pending_bytes > (signed) buffer->silence_bytes) {
+ *total_free_bytes = (buffer->free_bytes + buffer->silence_bytes);
+ } else {
+ *total_free_bytes = buffer->size;
+ buffer->silence_bytes = pending_bytes;
+ if (pending_bytes < 0) {
+ buffer->silence_pos = buffer->hw_pos;
+ buffer->silence_bytes = 0;
+ buffer->free_bytes = buffer->size;
+ DPF(1, "buffer underrun\n");
+ }
+ }
+}
+
+/**
+ * copy_block -
+ *
+ * copies a block of pcm data to a voice buffer.
+ * Notice that the voice buffer is actually a set of disjointed memory pages.
+ *
+ */
+static void copy_block(void **dst, u32 str, u8 __user *src, u32 len)
+{
+ unsigned int pg;
+ unsigned int pgoff;
+ unsigned int k;
+
+ pg = str / PAGE_SIZE;
+ pgoff = str % PAGE_SIZE;
+
+ if (len > PAGE_SIZE - pgoff) {
+ k = PAGE_SIZE - pgoff;
+ if (__copy_from_user((u8 *)dst[pg] + pgoff, src, k))
+ return;
+ len -= k;
+ while (len > PAGE_SIZE) {
+ if (__copy_from_user(dst[++pg], src + k, PAGE_SIZE))
+ return;
+ k += PAGE_SIZE;
+ len -= PAGE_SIZE;
+ }
+ if (__copy_from_user(dst[++pg], src + k, len))
+ return;
+
+ } else
+ __copy_from_user((u8 *)dst[pg] + pgoff, src, len);
+}
+
+/**
+ * copy_ilv_block -
+ *
+ * copies a block of pcm data containing n interleaved channels to n mono voice buffers.
+ * Notice that the voice buffer is actually a set of disjointed memory pages.
+ *
+ */
+static void copy_ilv_block(struct woinst *woinst, u32 str, u8 __user *src, u32 len)
+{
+ unsigned int pg;
+ unsigned int pgoff;
+ unsigned int voice_num;
+ struct emu_voice *voice = woinst->voice;
+
+ pg = str / PAGE_SIZE;
+ pgoff = str % PAGE_SIZE;
+
+ while (len) {
+ for (voice_num = 0; voice_num < woinst->num_voices; voice_num++) {
+ if (__copy_from_user((u8 *)(voice[voice_num].mem.addr[pg]) + pgoff, src, woinst->format.bytespervoicesample))
+ return;
+ src += woinst->format.bytespervoicesample;
+ }
+
+ len -= woinst->format.bytespervoicesample;
+
+ pgoff += woinst->format.bytespervoicesample;
+ if (pgoff >= PAGE_SIZE) {
+ pgoff = 0;
+ pg++;
+ }
+ }
+}
+
+/**
+ * fill_block -
+ *
+ * fills a set voice buffers with a block of a given sample.
+ *
+ */
+static void fill_block(struct woinst *woinst, u32 str, u8 data, u32 len)
+{
+ unsigned int pg;
+ unsigned int pgoff;
+ unsigned int voice_num;
+ struct emu_voice *voice = woinst->voice;
+ unsigned int k;
+
+ pg = str / PAGE_SIZE;
+ pgoff = str % PAGE_SIZE;
+
+ if (len > PAGE_SIZE - pgoff) {
+ k = PAGE_SIZE - pgoff;
+ for (voice_num = 0; voice_num < woinst->num_voices; voice_num++)
+ memset((u8 *)voice[voice_num].mem.addr[pg] + pgoff, data, k);
+ len -= k;
+ while (len > PAGE_SIZE) {
+ pg++;
+ for (voice_num = 0; voice_num < woinst->num_voices; voice_num++)
+ memset(voice[voice_num].mem.addr[pg], data, PAGE_SIZE);
+
+ len -= PAGE_SIZE;
+ }
+ pg++;
+ for (voice_num = 0; voice_num < woinst->num_voices; voice_num++)
+ memset(voice[voice_num].mem.addr[pg], data, len);
+
+ } else {
+ for (voice_num = 0; voice_num < woinst->num_voices; voice_num++)
+ memset((u8 *)voice[voice_num].mem.addr[pg] + pgoff, data, len);
+ }
+}
+
+/**
+ * emu10k1_waveout_xferdata -
+ *
+ * copies pcm data to the voice buffer. Silence samples
+ * previously added to the buffer are overwritten.
+ *
+ */
+void emu10k1_waveout_xferdata(struct woinst *woinst, u8 __user *data, u32 *size)
+{
+ struct waveout_buffer *buffer = &woinst->buffer;
+ struct voice_mem *mem = &woinst->voice[0].mem;
+ u32 sizetocopy, sizetocopy_now, start;
+ unsigned long flags;
+
+ sizetocopy = min_t(u32, buffer->size, *size);
+ *size = sizetocopy;
+
+ if (!sizetocopy)
+ return;
+
+ spin_lock_irqsave(&woinst->lock, flags);
+ start = (buffer->size + buffer->silence_pos - buffer->silence_bytes) % buffer->size;
+
+ if (sizetocopy > buffer->silence_bytes) {
+ buffer->silence_pos += sizetocopy - buffer->silence_bytes;
+ buffer->free_bytes -= sizetocopy - buffer->silence_bytes;
+ buffer->silence_bytes = 0;
+ } else
+ buffer->silence_bytes -= sizetocopy;
+
+ spin_unlock_irqrestore(&woinst->lock, flags);
+
+ sizetocopy_now = buffer->size - start;
+ if (sizetocopy > sizetocopy_now) {
+ sizetocopy -= sizetocopy_now;
+ if (woinst->num_voices > 1) {
+ copy_ilv_block(woinst, start, data, sizetocopy_now);
+ copy_ilv_block(woinst, 0, data + sizetocopy_now * woinst->num_voices, sizetocopy);
+ } else {
+ copy_block(mem->addr, start, data, sizetocopy_now);
+ copy_block(mem->addr, 0, data + sizetocopy_now, sizetocopy);
+ }
+ } else {
+ if (woinst->num_voices > 1)
+ copy_ilv_block(woinst, start, data, sizetocopy);
+ else
+ copy_block(mem->addr, start, data, sizetocopy);
+ }
+}
+
+/**
+ * emu10k1_waveout_fillsilence -
+ *
+ * adds samples of silence to the voice buffer so that we
+ * don't loop over stale pcm data.
+ *
+ */
+void emu10k1_waveout_fillsilence(struct woinst *woinst)
+{
+ struct waveout_buffer *buffer = &woinst->buffer;
+ u32 sizetocopy, sizetocopy_now, start;
+ u8 filldata;
+ unsigned long flags;
+
+ sizetocopy = buffer->fragment_size;
+
+ if (woinst->format.bitsperchannel == 16)
+ filldata = 0x00;
+ else
+ filldata = 0x80;
+
+ spin_lock_irqsave(&woinst->lock, flags);
+ buffer->silence_bytes += sizetocopy;
+ buffer->free_bytes -= sizetocopy;
+ buffer->silence_pos %= buffer->size;
+ start = buffer->silence_pos;
+ buffer->silence_pos += sizetocopy;
+ spin_unlock_irqrestore(&woinst->lock, flags);
+
+ sizetocopy_now = buffer->size - start;
+
+ if (sizetocopy > sizetocopy_now) {
+ sizetocopy -= sizetocopy_now;
+ fill_block(woinst, start, filldata, sizetocopy_now);
+ fill_block(woinst, 0, filldata, sizetocopy);
+ } else {
+ fill_block(woinst, start, filldata, sizetocopy);
+ }
+}
+
+/**
+ * emu10k1_waveout_update -
+ *
+ * updates the position of the voice buffer hardware pointer (hw_pos)
+ * and the number of free bytes on the buffer (free_bytes).
+ * The free bytes _don't_ include silence bytes that may have been
+ * added to the buffer.
+ *
+ */
+void emu10k1_waveout_update(struct woinst *woinst)
+{
+ u32 hw_pos;
+ u32 diff;
+
+ /* There is no actual start yet */
+ if (!(woinst->state & WAVE_STATE_STARTED)) {
+ hw_pos = woinst->buffer.hw_pos;
+ } else {
+ /* hw_pos in sample units */
+ hw_pos = sblive_readptr(woinst->voice[0].card, CCCA_CURRADDR, woinst->voice[0].num);
+
+ if(hw_pos < woinst->voice[0].start)
+ hw_pos += woinst->buffer.size / woinst->format.bytespervoicesample - woinst->voice[0].start;
+ else
+ hw_pos -= woinst->voice[0].start;
+
+ hw_pos *= woinst->format.bytespervoicesample;
+ }
+
+ diff = (woinst->buffer.size + hw_pos - woinst->buffer.hw_pos) % woinst->buffer.size;
+ woinst->total_played += diff;
+ woinst->buffer.free_bytes += diff;
+ woinst->buffer.hw_pos = hw_pos;
+}