Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 709 insertions, 0 deletions

diff --git a/sound/isa/sb/emu8000_pcm.c b/sound/isa/sb/emu8000_pcm.c
new file mode 100644
index 000000000..f46f6ec3e
--- /dev/null
+++ b/sound/isa/sb/emu8000_pcm.c
@@ -0,0 +1,709 @@
+/*
+ * pcm emulation on emu8000 wavetable
+ *
+ *  Copyright (C) 2002 Takashi Iwai <tiwai@suse.de>
+ *
+ *   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include "emu8000_local.h"
+
+#include <linux/sched/signal.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+
+/*
+ * define the following if you want to use this pcm with non-interleaved mode
+ */
+/* #define USE_NONINTERLEAVE */
+
+/* NOTE: for using the non-interleaved mode with alsa-lib, you have to set
+ * mmap_emulation flag to 1 in your .asoundrc, such like
+ *
+ *	pcm.emu8k {
+ *		type plug
+ *		slave.pcm {
+ *			type hw
+ *			card 0
+ *			device 1
+ *			mmap_emulation 1
+ *		}
+ *	}
+ *
+ * besides, for the time being, the non-interleaved mode doesn't work well on
+ * alsa-lib...
+ */
+
+
+struct snd_emu8k_pcm {
+	struct snd_emu8000 *emu;
+	struct snd_pcm_substream *substream;
+
+	unsigned int allocated_bytes;
+	struct snd_util_memblk *block;
+	unsigned int offset;
+	unsigned int buf_size;
+	unsigned int period_size;
+	unsigned int loop_start[2];
+	unsigned int pitch;
+	int panning[2];
+	int last_ptr;
+	int period_pos;
+	int voices;
+	unsigned int dram_opened: 1;
+	unsigned int running: 1;
+	unsigned int timer_running: 1;
+	struct timer_list timer;
+	spinlock_t timer_lock;
+};
+
+#define LOOP_BLANK_SIZE		8
+
+
+/*
+ * open up channels for the simultaneous data transfer and playback
+ */
+static int
+emu8k_open_dram_for_pcm(struct snd_emu8000 *emu, int channels)
+{
+	int i;
+
+	/* reserve up to 2 voices for playback */
+	snd_emux_lock_voice(emu->emu, 0);
+	if (channels > 1)
+		snd_emux_lock_voice(emu->emu, 1);
+
+	/* reserve 28 voices for loading */
+	for (i = channels + 1; i < EMU8000_DRAM_VOICES; i++) {
+		unsigned int mode = EMU8000_RAM_WRITE;
+		snd_emux_lock_voice(emu->emu, i);
+#ifndef USE_NONINTERLEAVE
+		if (channels > 1 && (i & 1) != 0)
+			mode |= EMU8000_RAM_RIGHT;
+#endif
+		snd_emu8000_dma_chan(emu, i, mode);
+	}
+
+	/* assign voice 31 and 32 to ROM */
+	EMU8000_VTFT_WRITE(emu, 30, 0);
+	EMU8000_PSST_WRITE(emu, 30, 0x1d8);
+	EMU8000_CSL_WRITE(emu, 30, 0x1e0);
+	EMU8000_CCCA_WRITE(emu, 30, 0x1d8);
+	EMU8000_VTFT_WRITE(emu, 31, 0);
+	EMU8000_PSST_WRITE(emu, 31, 0x1d8);
+	EMU8000_CSL_WRITE(emu, 31, 0x1e0);
+	EMU8000_CCCA_WRITE(emu, 31, 0x1d8);
+
+	return 0;
+}
+
+/*
+ */
+static void
+snd_emu8000_write_wait(struct snd_emu8000 *emu, int can_schedule)
+{
+	while ((EMU8000_SMALW_READ(emu) & 0x80000000) != 0) {
+		if (can_schedule) {
+			schedule_timeout_interruptible(1);
+			if (signal_pending(current))
+				break;
+		}
+	}
+}
+
+/*
+ * close all channels
+ */
+static void
+emu8k_close_dram(struct snd_emu8000 *emu)
+{
+	int i;
+
+	for (i = 0; i < 2; i++)
+		snd_emux_unlock_voice(emu->emu, i);
+	for (; i < EMU8000_DRAM_VOICES; i++) {
+		snd_emu8000_dma_chan(emu, i, EMU8000_RAM_CLOSE);
+		snd_emux_unlock_voice(emu->emu, i);
+	}
+}
+
+/*
+ * convert Hz to AWE32 rate offset (see emux/soundfont.c)
+ */
+
+#define OFFSET_SAMPLERATE	1011119		/* base = 44100 */
+#define SAMPLERATE_RATIO	4096
+
+static int calc_rate_offset(int hz)
+{
+	return snd_sf_linear_to_log(hz, OFFSET_SAMPLERATE, SAMPLERATE_RATIO);
+}
+
+
+/*
+ */
+
+static const struct snd_pcm_hardware emu8k_pcm_hw = {
+#ifdef USE_NONINTERLEAVE
+	.info =			SNDRV_PCM_INFO_NONINTERLEAVED,
+#else
+	.info =			SNDRV_PCM_INFO_INTERLEAVED,
+#endif
+	.formats =		SNDRV_PCM_FMTBIT_S16_LE,
+	.rates =		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
+	.rate_min =		4000,
+	.rate_max =		48000,
+	.channels_min =		1,
+	.channels_max =		2,
+	.buffer_bytes_max =	(128*1024),
+	.period_bytes_min =	1024,
+	.period_bytes_max =	(128*1024),
+	.periods_min =		2,
+	.periods_max =		1024,
+	.fifo_size =		0,
+
+};
+
+/*
+ * get the current position at the given channel from CCCA register
+ */
+static inline int emu8k_get_curpos(struct snd_emu8k_pcm *rec, int ch)
+{
+	int val = EMU8000_CCCA_READ(rec->emu, ch) & 0xfffffff;
+	val -= rec->loop_start[ch] - 1;
+	return val;
+}
+
+
+/*
+ * timer interrupt handler
+ * check the current position and update the period if necessary.
+ */
+static void emu8k_pcm_timer_func(struct timer_list *t)
+{
+	struct snd_emu8k_pcm *rec = from_timer(rec, t, timer);
+	int ptr, delta;
+
+	spin_lock(&rec->timer_lock);
+	/* update the current pointer */
+	ptr = emu8k_get_curpos(rec, 0);
+	if (ptr < rec->last_ptr)
+		delta = ptr + rec->buf_size - rec->last_ptr;
+	else
+		delta = ptr - rec->last_ptr;
+	rec->period_pos += delta;
+	rec->last_ptr = ptr;
+
+	/* reprogram timer */
+	mod_timer(&rec->timer, jiffies + 1);
+
+	/* update period */
+	if (rec->period_pos >= (int)rec->period_size) {
+		rec->period_pos %= rec->period_size;
+		spin_unlock(&rec->timer_lock);
+		snd_pcm_period_elapsed(rec->substream);
+		return;
+	}
+	spin_unlock(&rec->timer_lock);
+}
+
+
+/*
+ * open pcm
+ * creating an instance here
+ */
+static int emu8k_pcm_open(struct snd_pcm_substream *subs)
+{
+	struct snd_emu8000 *emu = snd_pcm_substream_chip(subs);
+	struct snd_emu8k_pcm *rec;
+	struct snd_pcm_runtime *runtime = subs->runtime;
+
+	rec = kzalloc(sizeof(*rec), GFP_KERNEL);
+	if (! rec)
+		return -ENOMEM;
+
+	rec->emu = emu;
+	rec->substream = subs;
+	runtime->private_data = rec;
+
+	spin_lock_init(&rec->timer_lock);
+	timer_setup(&rec->timer, emu8k_pcm_timer_func, 0);
+
+	runtime->hw = emu8k_pcm_hw;
+	runtime->hw.buffer_bytes_max = emu->mem_size - LOOP_BLANK_SIZE * 3;
+	runtime->hw.period_bytes_max = runtime->hw.buffer_bytes_max / 2;
+
+	/* use timer to update periods.. (specified in msec) */
+	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
+				     (1000000 + HZ - 1) / HZ, UINT_MAX);
+
+	return 0;
+}
+
+static int emu8k_pcm_close(struct snd_pcm_substream *subs)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+	kfree(rec);
+	subs->runtime->private_data = NULL;
+	return 0;
+}
+
+/*
+ * calculate pitch target
+ */
+static int calc_pitch_target(int pitch)
+{
+	int ptarget = 1 << (pitch >> 12);
+	if (pitch & 0x800) ptarget += (ptarget * 0x102e) / 0x2710;
+	if (pitch & 0x400) ptarget += (ptarget * 0x764) / 0x2710;
+	if (pitch & 0x200) ptarget += (ptarget * 0x389) / 0x2710;
+	ptarget += (ptarget >> 1);
+	if (ptarget > 0xffff) ptarget = 0xffff;
+	return ptarget;
+}
+
+/*
+ * set up the voice
+ */
+static void setup_voice(struct snd_emu8k_pcm *rec, int ch)
+{
+	struct snd_emu8000 *hw = rec->emu;
+	unsigned int temp;
+
+	/* channel to be silent and idle */
+	EMU8000_DCYSUSV_WRITE(hw, ch, 0x0080);
+	EMU8000_VTFT_WRITE(hw, ch, 0x0000FFFF);
+	EMU8000_CVCF_WRITE(hw, ch, 0x0000FFFF);
+	EMU8000_PTRX_WRITE(hw, ch, 0);
+	EMU8000_CPF_WRITE(hw, ch, 0);
+
+	/* pitch offset */
+	EMU8000_IP_WRITE(hw, ch, rec->pitch);
+	/* set envelope parameters */
+	EMU8000_ENVVAL_WRITE(hw, ch, 0x8000);
+	EMU8000_ATKHLD_WRITE(hw, ch, 0x7f7f);
+	EMU8000_DCYSUS_WRITE(hw, ch, 0x7f7f);
+	EMU8000_ENVVOL_WRITE(hw, ch, 0x8000);
+	EMU8000_ATKHLDV_WRITE(hw, ch, 0x7f7f);
+	/* decay/sustain parameter for volume envelope is used
+	   for triggerg the voice */
+	/* modulation envelope heights */
+	EMU8000_PEFE_WRITE(hw, ch, 0x0);
+	/* lfo1/2 delay */
+	EMU8000_LFO1VAL_WRITE(hw, ch, 0x8000);
+	EMU8000_LFO2VAL_WRITE(hw, ch, 0x8000);
+	/* lfo1 pitch & cutoff shift */
+	EMU8000_FMMOD_WRITE(hw, ch, 0);
+	/* lfo1 volume & freq */
+	EMU8000_TREMFRQ_WRITE(hw, ch, 0);
+	/* lfo2 pitch & freq */
+	EMU8000_FM2FRQ2_WRITE(hw, ch, 0);
+	/* pan & loop start */
+	temp = rec->panning[ch];
+	temp = (temp <<24) | ((unsigned int)rec->loop_start[ch] - 1);
+	EMU8000_PSST_WRITE(hw, ch, temp);
+	/* chorus & loop end (chorus 8bit, MSB) */
+	temp = 0; // chorus
+	temp = (temp << 24) | ((unsigned int)rec->loop_start[ch] + rec->buf_size - 1);
+	EMU8000_CSL_WRITE(hw, ch, temp);
+	/* Q & current address (Q 4bit value, MSB) */
+	temp = 0; // filterQ
+	temp = (temp << 28) | ((unsigned int)rec->loop_start[ch] - 1);
+	EMU8000_CCCA_WRITE(hw, ch, temp);
+	/* clear unknown registers */
+	EMU8000_00A0_WRITE(hw, ch, 0);
+	EMU8000_0080_WRITE(hw, ch, 0);
+}
+
+/*
+ * trigger the voice
+ */
+static void start_voice(struct snd_emu8k_pcm *rec, int ch)
+{
+	unsigned long flags;
+	struct snd_emu8000 *hw = rec->emu;
+	unsigned int temp, aux;
+	int pt = calc_pitch_target(rec->pitch);
+
+	/* cutoff and volume */
+	EMU8000_IFATN_WRITE(hw, ch, 0xff00);
+	EMU8000_VTFT_WRITE(hw, ch, 0xffff);
+	EMU8000_CVCF_WRITE(hw, ch, 0xffff);
+	/* trigger envelope */
+	EMU8000_DCYSUSV_WRITE(hw, ch, 0x7f7f);
+	/* set reverb and pitch target */
+	temp = 0; // reverb
+	if (rec->panning[ch] == 0)
+		aux = 0xff;
+	else
+		aux = (-rec->panning[ch]) & 0xff;
+	temp = (temp << 8) | (pt << 16) | aux;
+	EMU8000_PTRX_WRITE(hw, ch, temp);
+	EMU8000_CPF_WRITE(hw, ch, pt << 16);
+
+	/* start timer */
+	spin_lock_irqsave(&rec->timer_lock, flags);
+	if (! rec->timer_running) {
+		mod_timer(&rec->timer, jiffies + 1);
+		rec->timer_running = 1;
+	}
+	spin_unlock_irqrestore(&rec->timer_lock, flags);
+}
+
+/*
+ * stop the voice immediately
+ */
+static void stop_voice(struct snd_emu8k_pcm *rec, int ch)
+{
+	unsigned long flags;
+	struct snd_emu8000 *hw = rec->emu;
+
+	EMU8000_DCYSUSV_WRITE(hw, ch, 0x807F);
+
+	/* stop timer */
+	spin_lock_irqsave(&rec->timer_lock, flags);
+	if (rec->timer_running) {
+		del_timer(&rec->timer);
+		rec->timer_running = 0;
+	}
+	spin_unlock_irqrestore(&rec->timer_lock, flags);
+}
+
+static int emu8k_pcm_trigger(struct snd_pcm_substream *subs, int cmd)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+	int ch;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		for (ch = 0; ch < rec->voices; ch++)
+			start_voice(rec, ch);
+		rec->running = 1;
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+		rec->running = 0;
+		for (ch = 0; ch < rec->voices; ch++)
+			stop_voice(rec, ch);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+
+/*
+ * copy / silence ops
+ */
+
+/*
+ * this macro should be inserted in the copy/silence loops
+ * to reduce the latency.  without this, the system will hang up
+ * during the whole loop.
+ */
+#define CHECK_SCHEDULER() \
+do { \
+	cond_resched();\
+	if (signal_pending(current))\
+		return -EAGAIN;\
+} while (0)
+
+enum {
+	COPY_USER, COPY_KERNEL, FILL_SILENCE,
+};
+
+#define GET_VAL(sval, buf, mode)					\
+	do {								\
+		switch (mode) {						\
+		case FILL_SILENCE:					\
+			sval = 0;					\
+			break;						\
+		case COPY_KERNEL:					\
+			sval = *buf++;					\
+			break;						\
+		default:						\
+			if (get_user(sval, (unsigned short __user *)buf)) \
+				return -EFAULT;				\
+			buf++;						\
+			break;						\
+		}							\
+	} while (0)
+
+#ifdef USE_NONINTERLEAVE
+
+#define LOOP_WRITE(rec, offset, _buf, count, mode)		\
+	do {							\
+		struct snd_emu8000 *emu = (rec)->emu;		\
+		unsigned short *buf = (unsigned short *)(_buf); \
+		snd_emu8000_write_wait(emu, 1);			\
+		EMU8000_SMALW_WRITE(emu, offset);		\
+		while (count > 0) {				\
+			unsigned short sval;			\
+			CHECK_SCHEDULER();			\
+			GET_VAL(sval, buf, mode);		\
+			EMU8000_SMLD_WRITE(emu, sval);		\
+			count--;				\
+		}						\
+	} while (0)
+
+/* copy one channel block */
+static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
+			  int voice, unsigned long pos,
+			  void __user *src, unsigned long count)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	/* convert to word unit */
+	pos = (pos << 1) + rec->loop_start[voice];
+	count <<= 1;
+	LOOP_WRITE(rec, pos, src, count, COPY_USER);
+	return 0;
+}
+
+static int emu8k_pcm_copy_kernel(struct snd_pcm_substream *subs,
+				 int voice, unsigned long pos,
+				 void *src, unsigned long count)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	/* convert to word unit */
+	pos = (pos << 1) + rec->loop_start[voice];
+	count <<= 1;
+	LOOP_WRITE(rec, pos, src, count, COPY_KERNEL);
+	return 0;
+}
+
+/* make a channel block silence */
+static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
+			     int voice, unsigned long pos, unsigned long count)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	/* convert to word unit */
+	pos = (pos << 1) + rec->loop_start[voice];
+	count <<= 1;
+	LOOP_WRITE(rec, pos, NULL, count, FILL_SILENCE);
+	return 0;
+}
+
+#else /* interleave */
+
+#define LOOP_WRITE(rec, pos, _buf, count, mode)				\
+	do {								\
+		struct snd_emu8000 *emu = rec->emu;			\
+		unsigned short *buf = (unsigned short *)(_buf);		\
+		snd_emu8000_write_wait(emu, 1);				\
+		EMU8000_SMALW_WRITE(emu, pos + rec->loop_start[0]);	\
+		if (rec->voices > 1)					\
+			EMU8000_SMARW_WRITE(emu, pos + rec->loop_start[1]); \
+		while (count > 0) {					\
+			unsigned short sval;				\
+			CHECK_SCHEDULER();				\
+			GET_VAL(sval, buf, mode);			\
+			EMU8000_SMLD_WRITE(emu, sval);			\
+			if (rec->voices > 1) {				\
+				CHECK_SCHEDULER();			\
+				GET_VAL(sval, buf, mode);		\
+				EMU8000_SMRD_WRITE(emu, sval);		\
+			}						\
+			count--;					\
+		}							\
+	} while (0)
+
+
+/*
+ * copy the interleaved data can be done easily by using
+ * DMA "left" and "right" channels on emu8k engine.
+ */
+static int emu8k_pcm_copy(struct snd_pcm_substream *subs,
+			  int voice, unsigned long pos,
+			  void __user *src, unsigned long count)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	/* convert to frames */
+	pos = bytes_to_frames(subs->runtime, pos);
+	count = bytes_to_frames(subs->runtime, count);
+	LOOP_WRITE(rec, pos, src, count, COPY_USER);
+	return 0;
+}
+
+static int emu8k_pcm_copy_kernel(struct snd_pcm_substream *subs,
+				 int voice, unsigned long pos,
+				 void *src, unsigned long count)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	/* convert to frames */
+	pos = bytes_to_frames(subs->runtime, pos);
+	count = bytes_to_frames(subs->runtime, count);
+	LOOP_WRITE(rec, pos, src, count, COPY_KERNEL);
+	return 0;
+}
+
+static int emu8k_pcm_silence(struct snd_pcm_substream *subs,
+			     int voice, unsigned long pos, unsigned long count)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	/* convert to frames */
+	pos = bytes_to_frames(subs->runtime, pos);
+	count = bytes_to_frames(subs->runtime, count);
+	LOOP_WRITE(rec, pos, NULL, count, FILL_SILENCE);
+	return 0;
+}
+#endif
+
+
+/*
+ * allocate a memory block
+ */
+static int emu8k_pcm_hw_params(struct snd_pcm_substream *subs,
+			       struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	if (rec->block) {
+		/* reallocation - release the old block */
+		snd_util_mem_free(rec->emu->memhdr, rec->block);
+		rec->block = NULL;
+	}
+
+	rec->allocated_bytes = params_buffer_bytes(hw_params) + LOOP_BLANK_SIZE * 4;
+	rec->block = snd_util_mem_alloc(rec->emu->memhdr, rec->allocated_bytes);
+	if (! rec->block)
+		return -ENOMEM;
+	rec->offset = EMU8000_DRAM_OFFSET + (rec->block->offset >> 1); /* in word */
+	/* at least dma_bytes must be set for non-interleaved mode */
+	subs->dma_buffer.bytes = params_buffer_bytes(hw_params);
+
+	return 0;
+}
+
+/*
+ * free the memory block
+ */
+static int emu8k_pcm_hw_free(struct snd_pcm_substream *subs)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	if (rec->block) {
+		int ch;
+		for (ch = 0; ch < rec->voices; ch++)
+			stop_voice(rec, ch); // to be sure
+		if (rec->dram_opened)
+			emu8k_close_dram(rec->emu);
+		snd_util_mem_free(rec->emu->memhdr, rec->block);
+		rec->block = NULL;
+	}
+	return 0;
+}
+
+/*
+ */
+static int emu8k_pcm_prepare(struct snd_pcm_substream *subs)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+
+	rec->pitch = 0xe000 + calc_rate_offset(subs->runtime->rate);
+	rec->last_ptr = 0;
+	rec->period_pos = 0;
+
+	rec->buf_size = subs->runtime->buffer_size;
+	rec->period_size = subs->runtime->period_size;
+	rec->voices = subs->runtime->channels;
+	rec->loop_start[0] = rec->offset + LOOP_BLANK_SIZE;
+	if (rec->voices > 1)
+		rec->loop_start[1] = rec->loop_start[0] + rec->buf_size + LOOP_BLANK_SIZE;
+	if (rec->voices > 1) {
+		rec->panning[0] = 0xff;
+		rec->panning[1] = 0x00;
+	} else
+		rec->panning[0] = 0x80;
+
+	if (! rec->dram_opened) {
+		int err, i, ch;
+
+		snd_emux_terminate_all(rec->emu->emu);
+		if ((err = emu8k_open_dram_for_pcm(rec->emu, rec->voices)) != 0)
+			return err;
+		rec->dram_opened = 1;
+
+		/* clear loop blanks */
+		snd_emu8000_write_wait(rec->emu, 0);
+		EMU8000_SMALW_WRITE(rec->emu, rec->offset);
+		for (i = 0; i < LOOP_BLANK_SIZE; i++)
+			EMU8000_SMLD_WRITE(rec->emu, 0);
+		for (ch = 0; ch < rec->voices; ch++) {
+			EMU8000_SMALW_WRITE(rec->emu, rec->loop_start[ch] + rec->buf_size);
+			for (i = 0; i < LOOP_BLANK_SIZE; i++)
+				EMU8000_SMLD_WRITE(rec->emu, 0);
+		}
+	}
+
+	setup_voice(rec, 0);
+	if (rec->voices > 1)
+		setup_voice(rec, 1);
+	return 0;
+}
+
+static snd_pcm_uframes_t emu8k_pcm_pointer(struct snd_pcm_substream *subs)
+{
+	struct snd_emu8k_pcm *rec = subs->runtime->private_data;
+	if (rec->running)
+		return emu8k_get_curpos(rec, 0);
+	return 0;
+}
+
+
+static const struct snd_pcm_ops emu8k_pcm_ops = {
+	.open =		emu8k_pcm_open,
+	.close =	emu8k_pcm_close,
+	.ioctl =	snd_pcm_lib_ioctl,
+	.hw_params =	emu8k_pcm_hw_params,
+	.hw_free =	emu8k_pcm_hw_free,
+	.prepare =	emu8k_pcm_prepare,
+	.trigger =	emu8k_pcm_trigger,
+	.pointer =	emu8k_pcm_pointer,
+	.copy_user =	emu8k_pcm_copy,
+	.copy_kernel =	emu8k_pcm_copy_kernel,
+	.fill_silence =	emu8k_pcm_silence,
+};
+
+
+static void snd_emu8000_pcm_free(struct snd_pcm *pcm)
+{
+	struct snd_emu8000 *emu = pcm->private_data;
+	emu->pcm = NULL;
+}
+
+int snd_emu8000_pcm_new(struct snd_card *card, struct snd_emu8000 *emu, int index)
+{
+	struct snd_pcm *pcm;
+	int err;
+
+	if ((err = snd_pcm_new(card, "Emu8000 PCM", index, 1, 0, &pcm)) < 0)
+		return err;
+	pcm->private_data = emu;
+	pcm->private_free = snd_emu8000_pcm_free;
+	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &emu8k_pcm_ops);
+	emu->pcm = pcm;
+
+	snd_device_register(card, pcm);
+
+	return 0;
+}