Adding upstream version 6.1.76.upstream/6.1.76

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

1 files changed, 1229 insertions, 0 deletions

diff --git a/sound/drivers/vx/vx_pcm.c b/sound/drivers/vx/vx_pcm.c
new file mode 100644
index 000000000..ceaeb2570
--- /dev/null
+++ b/sound/drivers/vx/vx_pcm.c
@@ -0,0 +1,1229 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for Digigram VX soundcards
+ *
+ * PCM part
+ *
+ * Copyright (c) 2002,2003 by Takashi Iwai <tiwai@suse.de>
+ *
+ * STRATEGY
+ *  for playback, we send series of "chunks", which size is equal with the
+ *  IBL size, typically 126 samples.  at each end of chunk, the end-of-buffer
+ *  interrupt is notified, and the interrupt handler will feed the next chunk.
+ *
+ *  the current position is calculated from the sample count RMH.
+ *  pipe->transferred is the counter of data which has been already transferred.
+ *  if this counter reaches to the period size, snd_pcm_period_elapsed() will
+ *  be issued.
+ *
+ *  for capture, the situation is much easier.
+ *  to get a low latency response, we'll check the capture streams at each
+ *  interrupt (capture stream has no EOB notification).  if the pending
+ *  data is accumulated to the period size, snd_pcm_period_elapsed() is
+ *  called and the pointer is updated.
+ *
+ *  the current point of read buffer is kept in pipe->hw_ptr.  note that
+ *  this is in bytes.
+ *
+ * TODO
+ *  - linked trigger for full-duplex mode.
+ *  - scheduled action on the stream.
+ */
+
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <sound/core.h>
+#include <sound/asoundef.h>
+#include <sound/pcm.h>
+#include <sound/vx_core.h>
+#include "vx_cmd.h"
+
+
+/*
+ * read three pending pcm bytes via inb()
+ */
+static void vx_pcm_read_per_bytes(struct vx_core *chip, struct snd_pcm_runtime *runtime,
+				  struct vx_pipe *pipe)
+{
+	int offset = pipe->hw_ptr;
+	unsigned char *buf = (unsigned char *)(runtime->dma_area + offset);
+	*buf++ = vx_inb(chip, RXH);
+	if (++offset >= pipe->buffer_bytes) {
+		offset = 0;
+		buf = (unsigned char *)runtime->dma_area;
+	}
+	*buf++ = vx_inb(chip, RXM);
+	if (++offset >= pipe->buffer_bytes) {
+		offset = 0;
+		buf = (unsigned char *)runtime->dma_area;
+	}
+	*buf++ = vx_inb(chip, RXL);
+	if (++offset >= pipe->buffer_bytes) {
+		offset = 0;
+	}
+	pipe->hw_ptr = offset;
+}
+
+/*
+ * vx_set_pcx_time - convert from the PC time to the RMH status time.
+ * @pc_time: the pointer for the PC-time to set
+ * @dsp_time: the pointer for RMH status time array
+ */
+static void vx_set_pcx_time(struct vx_core *chip, pcx_time_t *pc_time,
+			    unsigned int *dsp_time)
+{
+	dsp_time[0] = (unsigned int)((*pc_time) >> 24) & PCX_TIME_HI_MASK;
+	dsp_time[1] = (unsigned int)(*pc_time) &  MASK_DSP_WORD;
+}
+
+/*
+ * vx_set_differed_time - set the differed time if specified
+ * @rmh: the rmh record to modify
+ * @pipe: the pipe to be checked
+ *
+ * if the pipe is programmed with the differed time, set the DSP time
+ * on the rmh and changes its command length.
+ *
+ * returns the increase of the command length.
+ */
+static int vx_set_differed_time(struct vx_core *chip, struct vx_rmh *rmh,
+				struct vx_pipe *pipe)
+{
+	/* Update The length added to the RMH command by the timestamp */
+	if (! (pipe->differed_type & DC_DIFFERED_DELAY))
+		return 0;
+		
+	/* Set the T bit */
+	rmh->Cmd[0] |= DSP_DIFFERED_COMMAND_MASK;
+
+	/* Time stamp is the 1st following parameter */
+	vx_set_pcx_time(chip, &pipe->pcx_time, &rmh->Cmd[1]);
+
+	/* Add the flags to a notified differed command */
+	if (pipe->differed_type & DC_NOTIFY_DELAY)
+		rmh->Cmd[1] |= NOTIFY_MASK_TIME_HIGH ;
+
+	/* Add the flags to a multiple differed command */
+	if (pipe->differed_type & DC_MULTIPLE_DELAY)
+		rmh->Cmd[1] |= MULTIPLE_MASK_TIME_HIGH;
+
+	/* Add the flags to a stream-time differed command */
+	if (pipe->differed_type & DC_STREAM_TIME_DELAY)
+		rmh->Cmd[1] |= STREAM_MASK_TIME_HIGH;
+		
+	rmh->LgCmd += 2;
+	return 2;
+}
+
+/*
+ * vx_set_stream_format - send the stream format command
+ * @pipe: the affected pipe
+ * @data: format bitmask
+ */
+static int vx_set_stream_format(struct vx_core *chip, struct vx_pipe *pipe,
+				unsigned int data)
+{
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, pipe->is_capture ?
+		    CMD_FORMAT_STREAM_IN : CMD_FORMAT_STREAM_OUT);
+	rmh.Cmd[0] |= pipe->number << FIELD_SIZE;
+
+        /* Command might be longer since we may have to add a timestamp */
+	vx_set_differed_time(chip, &rmh, pipe);
+
+	rmh.Cmd[rmh.LgCmd] = (data & 0xFFFFFF00) >> 8;
+	rmh.Cmd[rmh.LgCmd + 1] = (data & 0xFF) << 16 /*| (datal & 0xFFFF00) >> 8*/;
+	rmh.LgCmd += 2;
+    
+	return vx_send_msg(chip, &rmh);
+}
+
+
+/*
+ * vx_set_format - set the format of a pipe
+ * @pipe: the affected pipe
+ * @runtime: pcm runtime instance to be referred
+ *
+ * returns 0 if successful, or a negative error code.
+ */
+static int vx_set_format(struct vx_core *chip, struct vx_pipe *pipe,
+			 struct snd_pcm_runtime *runtime)
+{
+	unsigned int header = HEADER_FMT_BASE;
+
+	if (runtime->channels == 1)
+		header |= HEADER_FMT_MONO;
+	if (snd_pcm_format_little_endian(runtime->format))
+		header |= HEADER_FMT_INTEL;
+	if (runtime->rate < 32000 && runtime->rate > 11025)
+		header |= HEADER_FMT_UPTO32;
+	else if (runtime->rate <= 11025)
+		header |= HEADER_FMT_UPTO11;
+
+	switch (snd_pcm_format_physical_width(runtime->format)) {
+	// case 8: break;
+	case 16: header |= HEADER_FMT_16BITS; break;
+	case 24: header |= HEADER_FMT_24BITS; break;
+	default : 
+		snd_BUG();
+		return -EINVAL;
+	}
+
+	return vx_set_stream_format(chip, pipe, header);
+}
+
+/*
+ * set / query the IBL size
+ */
+static int vx_set_ibl(struct vx_core *chip, struct vx_ibl_info *info)
+{
+	int err;
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, CMD_IBL);
+	rmh.Cmd[0] |= info->size & 0x03ffff;
+	err = vx_send_msg(chip, &rmh);
+	if (err < 0)
+		return err;
+	info->size = rmh.Stat[0];
+	info->max_size = rmh.Stat[1];
+	info->min_size = rmh.Stat[2];
+	info->granularity = rmh.Stat[3];
+	snd_printdd(KERN_DEBUG "vx_set_ibl: size = %d, max = %d, min = %d, gran = %d\n",
+		   info->size, info->max_size, info->min_size, info->granularity);
+	return 0;
+}
+
+
+/*
+ * vx_get_pipe_state - get the state of a pipe
+ * @pipe: the pipe to be checked
+ * @state: the pointer for the returned state
+ *
+ * checks the state of a given pipe, and stores the state (1 = running,
+ * 0 = paused) on the given pointer.
+ *
+ * called from trigger callback only
+ */
+static int vx_get_pipe_state(struct vx_core *chip, struct vx_pipe *pipe, int *state)
+{
+	int err;
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, CMD_PIPE_STATE);
+	vx_set_pipe_cmd_params(&rmh, pipe->is_capture, pipe->number, 0);
+	err = vx_send_msg(chip, &rmh);
+	if (! err)
+		*state = (rmh.Stat[0] & (1 << pipe->number)) ? 1 : 0;
+	return err;
+}
+
+
+/*
+ * vx_query_hbuffer_size - query available h-buffer size in bytes
+ * @pipe: the pipe to be checked
+ *
+ * return the available size on h-buffer in bytes,
+ * or a negative error code.
+ *
+ * NOTE: calling this function always switches to the stream mode.
+ *       you'll need to disconnect the host to get back to the
+ *       normal mode.
+ */
+static int vx_query_hbuffer_size(struct vx_core *chip, struct vx_pipe *pipe)
+{
+	int result;
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, CMD_SIZE_HBUFFER);
+	vx_set_pipe_cmd_params(&rmh, pipe->is_capture, pipe->number, 0);
+	if (pipe->is_capture)
+		rmh.Cmd[0] |= 0x00000001;
+	result = vx_send_msg(chip, &rmh);
+	if (! result)
+		result = rmh.Stat[0] & 0xffff;
+	return result;
+}
+
+
+/*
+ * vx_pipe_can_start - query whether a pipe is ready for start
+ * @pipe: the pipe to be checked
+ *
+ * return 1 if ready, 0 if not ready, and negative value on error.
+ *
+ * called from trigger callback only
+ */
+static int vx_pipe_can_start(struct vx_core *chip, struct vx_pipe *pipe)
+{
+	int err;
+	struct vx_rmh rmh;
+        
+	vx_init_rmh(&rmh, CMD_CAN_START_PIPE);
+	vx_set_pipe_cmd_params(&rmh, pipe->is_capture, pipe->number, 0);
+	rmh.Cmd[0] |= 1;
+
+	err = vx_send_msg(chip, &rmh);
+	if (! err) {
+		if (rmh.Stat[0])
+			err = 1;
+	}
+	return err;
+}
+
+/*
+ * vx_conf_pipe - tell the pipe to stand by and wait for IRQA.
+ * @pipe: the pipe to be configured
+ */
+static int vx_conf_pipe(struct vx_core *chip, struct vx_pipe *pipe)
+{
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, CMD_CONF_PIPE);
+	if (pipe->is_capture)
+		rmh.Cmd[0] |= COMMAND_RECORD_MASK;
+	rmh.Cmd[1] = 1 << pipe->number;
+	return vx_send_msg(chip, &rmh);
+}
+
+/*
+ * vx_send_irqa - trigger IRQA
+ */
+static int vx_send_irqa(struct vx_core *chip)
+{
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, CMD_SEND_IRQA);
+	return vx_send_msg(chip, &rmh);
+}
+
+
+#define MAX_WAIT_FOR_DSP        250
+/*
+ * vx boards do not support inter-card sync, besides
+ * only 126 samples require to be prepared before a pipe can start
+ */
+#define CAN_START_DELAY         2	/* wait 2ms only before asking if the pipe is ready*/
+#define WAIT_STATE_DELAY        2	/* wait 2ms after irqA was requested and check if the pipe state toggled*/
+
+/*
+ * vx_toggle_pipe - start / pause a pipe
+ * @pipe: the pipe to be triggered
+ * @state: start = 1, pause = 0
+ *
+ * called from trigger callback only
+ *
+ */
+static int vx_toggle_pipe(struct vx_core *chip, struct vx_pipe *pipe, int state)
+{
+	int err, i, cur_state;
+
+	/* Check the pipe is not already in the requested state */
+	if (vx_get_pipe_state(chip, pipe, &cur_state) < 0)
+		return -EBADFD;
+	if (state == cur_state)
+		return 0;
+
+	/* If a start is requested, ask the DSP to get prepared
+	 * and wait for a positive acknowledge (when there are
+	 * enough sound buffer for this pipe)
+	 */
+	if (state) {
+		for (i = 0 ; i < MAX_WAIT_FOR_DSP; i++) {
+			err = vx_pipe_can_start(chip, pipe);
+			if (err > 0)
+				break;
+			/* Wait for a few, before asking again
+			 * to avoid flooding the DSP with our requests
+			 */
+			mdelay(1);
+		}
+	}
+    
+	err = vx_conf_pipe(chip, pipe);
+	if (err < 0)
+		return err;
+
+	err = vx_send_irqa(chip);
+	if (err < 0)
+		return err;
+    
+	/* If it completes successfully, wait for the pipes
+	 * reaching the expected state before returning
+	 * Check one pipe only (since they are synchronous)
+	 */
+	for (i = 0; i < MAX_WAIT_FOR_DSP; i++) {
+		err = vx_get_pipe_state(chip, pipe, &cur_state);
+		if (err < 0 || cur_state == state)
+			break;
+		err = -EIO;
+		mdelay(1);
+	}
+	return err < 0 ? -EIO : 0;
+}
+
+    
+/*
+ * vx_stop_pipe - stop a pipe
+ * @pipe: the pipe to be stopped
+ *
+ * called from trigger callback only
+ */
+static int vx_stop_pipe(struct vx_core *chip, struct vx_pipe *pipe)
+{
+	struct vx_rmh rmh;
+	vx_init_rmh(&rmh, CMD_STOP_PIPE);
+	vx_set_pipe_cmd_params(&rmh, pipe->is_capture, pipe->number, 0);
+	return vx_send_msg(chip, &rmh);
+}
+
+
+/*
+ * vx_alloc_pipe - allocate a pipe and initialize the pipe instance
+ * @capture: 0 = playback, 1 = capture operation
+ * @audioid: the audio id to be assigned
+ * @num_audio: number of audio channels
+ * @pipep: the returned pipe instance
+ *
+ * return 0 on success, or a negative error code.
+ */
+static int vx_alloc_pipe(struct vx_core *chip, int capture,
+			 int audioid, int num_audio,
+			 struct vx_pipe **pipep)
+{
+	int err;
+	struct vx_pipe *pipe;
+	struct vx_rmh rmh;
+	int data_mode;
+
+	*pipep = NULL;
+	vx_init_rmh(&rmh, CMD_RES_PIPE);
+	vx_set_pipe_cmd_params(&rmh, capture, audioid, num_audio);
+#if 0	// NYI
+	if (underrun_skip_sound)
+		rmh.Cmd[0] |= BIT_SKIP_SOUND;
+#endif	// NYI
+	data_mode = (chip->uer_bits & IEC958_AES0_NONAUDIO) != 0;
+	if (! capture && data_mode)
+		rmh.Cmd[0] |= BIT_DATA_MODE;
+	err = vx_send_msg(chip, &rmh);
+	if (err < 0)
+		return err;
+
+	/* initialize the pipe record */
+	pipe = kzalloc(sizeof(*pipe), GFP_KERNEL);
+	if (! pipe) {
+		/* release the pipe */
+		vx_init_rmh(&rmh, CMD_FREE_PIPE);
+		vx_set_pipe_cmd_params(&rmh, capture, audioid, 0);
+		vx_send_msg(chip, &rmh);
+		return -ENOMEM;
+	}
+
+	/* the pipe index should be identical with the audio index */
+	pipe->number = audioid;
+	pipe->is_capture = capture;
+	pipe->channels = num_audio;
+	pipe->differed_type = 0;
+	pipe->pcx_time = 0;
+	pipe->data_mode = data_mode;
+	*pipep = pipe;
+
+	return 0;
+}
+
+
+/*
+ * vx_free_pipe - release a pipe
+ * @pipe: pipe to be released
+ */
+static int vx_free_pipe(struct vx_core *chip, struct vx_pipe *pipe)
+{
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, CMD_FREE_PIPE);
+	vx_set_pipe_cmd_params(&rmh, pipe->is_capture, pipe->number, 0);
+	vx_send_msg(chip, &rmh);
+
+	kfree(pipe);
+	return 0;
+}
+
+
+/*
+ * vx_start_stream - start the stream
+ *
+ * called from trigger callback only
+ */
+static int vx_start_stream(struct vx_core *chip, struct vx_pipe *pipe)
+{
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, CMD_START_ONE_STREAM);
+	vx_set_stream_cmd_params(&rmh, pipe->is_capture, pipe->number);
+	vx_set_differed_time(chip, &rmh, pipe);
+	return vx_send_msg(chip, &rmh);
+}
+
+
+/*
+ * vx_stop_stream - stop the stream
+ *
+ * called from trigger callback only
+ */
+static int vx_stop_stream(struct vx_core *chip, struct vx_pipe *pipe)
+{
+	struct vx_rmh rmh;
+
+	vx_init_rmh(&rmh, CMD_STOP_STREAM);
+	vx_set_stream_cmd_params(&rmh, pipe->is_capture, pipe->number);
+	return vx_send_msg(chip, &rmh);
+}
+
+
+/*
+ * playback hw information
+ */
+
+static const struct snd_pcm_hardware vx_pcm_playback_hw = {
+	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
+				 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_MMAP_VALID /*|*/
+				 /*SNDRV_PCM_INFO_RESUME*/),
+	.formats =		(/*SNDRV_PCM_FMTBIT_U8 |*/
+				 SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_3LE),
+	.rates =		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
+	.rate_min =		5000,
+	.rate_max =		48000,
+	.channels_min =		1,
+	.channels_max =		2,
+	.buffer_bytes_max =	(128*1024),
+	.period_bytes_min =	126,
+	.period_bytes_max =	(128*1024),
+	.periods_min =		2,
+	.periods_max =		VX_MAX_PERIODS,
+	.fifo_size =		126,
+};
+
+
+/*
+ * vx_pcm_playback_open - open callback for playback
+ */
+static int vx_pcm_playback_open(struct snd_pcm_substream *subs)
+{
+	struct snd_pcm_runtime *runtime = subs->runtime;
+	struct vx_core *chip = snd_pcm_substream_chip(subs);
+	struct vx_pipe *pipe = NULL;
+	unsigned int audio;
+	int err;
+
+	if (chip->chip_status & VX_STAT_IS_STALE)
+		return -EBUSY;
+
+	audio = subs->pcm->device * 2;
+	if (snd_BUG_ON(audio >= chip->audio_outs))
+		return -EINVAL;
+	
+	/* playback pipe may have been already allocated for monitoring */
+	pipe = chip->playback_pipes[audio];
+	if (! pipe) {
+		/* not allocated yet */
+		err = vx_alloc_pipe(chip, 0, audio, 2, &pipe); /* stereo playback */
+		if (err < 0)
+			return err;
+	}
+	/* open for playback */
+	pipe->references++;
+
+	pipe->substream = subs;
+	chip->playback_pipes[audio] = pipe;
+
+	runtime->hw = vx_pcm_playback_hw;
+	runtime->hw.period_bytes_min = chip->ibl.size;
+	runtime->private_data = pipe;
+
+	/* align to 4 bytes (otherwise will be problematic when 24bit is used) */ 
+	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 4);
+	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 4);
+
+	return 0;
+}
+
+/*
+ * vx_pcm_playback_close - close callback for playback
+ */
+static int vx_pcm_playback_close(struct snd_pcm_substream *subs)
+{
+	struct vx_core *chip = snd_pcm_substream_chip(subs);
+	struct vx_pipe *pipe;
+
+	if (! subs->runtime->private_data)
+		return -EINVAL;
+
+	pipe = subs->runtime->private_data;
+
+	if (--pipe->references == 0) {
+		chip->playback_pipes[pipe->number] = NULL;
+		vx_free_pipe(chip, pipe);
+	}
+
+	return 0;
+
+}
+
+
+/*
+ * vx_notify_end_of_buffer - send "end-of-buffer" notifier at the given pipe
+ * @pipe: the pipe to notify
+ *
+ * NB: call with a certain lock.
+ */
+static int vx_notify_end_of_buffer(struct vx_core *chip, struct vx_pipe *pipe)
+{
+	int err;
+	struct vx_rmh rmh;  /* use a temporary rmh here */
+
+	/* Toggle Dsp Host Interface into Message mode */
+	vx_send_rih_nolock(chip, IRQ_PAUSE_START_CONNECT);
+	vx_init_rmh(&rmh, CMD_NOTIFY_END_OF_BUFFER);
+	vx_set_stream_cmd_params(&rmh, 0, pipe->number);
+	err = vx_send_msg_nolock(chip, &rmh);
+	if (err < 0)
+		return err;
+	/* Toggle Dsp Host Interface back to sound transfer mode */
+	vx_send_rih_nolock(chip, IRQ_PAUSE_START_CONNECT);
+	return 0;
+}
+
+/*
+ * vx_pcm_playback_transfer_chunk - transfer a single chunk
+ * @subs: substream
+ * @pipe: the pipe to transfer
+ * @size: chunk size in bytes
+ *
+ * transfer a single buffer chunk.  EOB notificaton is added after that.
+ * called from the interrupt handler, too.
+ *
+ * return 0 if ok.
+ */
+static int vx_pcm_playback_transfer_chunk(struct vx_core *chip,
+					  struct snd_pcm_runtime *runtime,
+					  struct vx_pipe *pipe, int size)
+{
+	int space, err = 0;
+
+	space = vx_query_hbuffer_size(chip, pipe);
+	if (space < 0) {
+		/* disconnect the host, SIZE_HBUF command always switches to the stream mode */
+		vx_send_rih(chip, IRQ_CONNECT_STREAM_NEXT);
+		snd_printd("error hbuffer\n");
+		return space;
+	}
+	if (space < size) {
+		vx_send_rih(chip, IRQ_CONNECT_STREAM_NEXT);
+		snd_printd("no enough hbuffer space %d\n", space);
+		return -EIO; /* XRUN */
+	}
+		
+	/* we don't need irqsave here, because this function
+	 * is called from either trigger callback or irq handler
+	 */
+	mutex_lock(&chip->lock);
+	vx_pseudo_dma_write(chip, runtime, pipe, size);
+	err = vx_notify_end_of_buffer(chip, pipe);
+	/* disconnect the host, SIZE_HBUF command always switches to the stream mode */
+	vx_send_rih_nolock(chip, IRQ_CONNECT_STREAM_NEXT);
+	mutex_unlock(&chip->lock);
+	return err;
+}
+
+/*
+ * update the position of the given pipe.
+ * pipe->position is updated and wrapped within the buffer size.
+ * pipe->transferred is updated, too, but the size is not wrapped,
+ * so that the caller can check the total transferred size later
+ * (to call snd_pcm_period_elapsed).
+ */
+static int vx_update_pipe_position(struct vx_core *chip,
+				   struct snd_pcm_runtime *runtime,
+				   struct vx_pipe *pipe)
+{
+	struct vx_rmh rmh;
+	int err, update;
+	u64 count;
+
+	vx_init_rmh(&rmh, CMD_STREAM_SAMPLE_COUNT);
+	vx_set_pipe_cmd_params(&rmh, pipe->is_capture, pipe->number, 0);
+	err = vx_send_msg(chip, &rmh);
+	if (err < 0)
+		return err;
+
+	count = ((u64)(rmh.Stat[0] & 0xfffff) << 24) | (u64)rmh.Stat[1];
+	update = (int)(count - pipe->cur_count);
+	pipe->cur_count = count;
+	pipe->position += update;
+	if (pipe->position >= (int)runtime->buffer_size)
+		pipe->position %= runtime->buffer_size;
+	pipe->transferred += update;
+	return 0;
+}
+
+/*
+ * transfer the pending playback buffer data to DSP
+ * called from interrupt handler
+ */
+static void vx_pcm_playback_transfer(struct vx_core *chip,
+				     struct snd_pcm_substream *subs,
+				     struct vx_pipe *pipe, int nchunks)
+{
+	int i, err;
+	struct snd_pcm_runtime *runtime = subs->runtime;
+
+	if (! pipe->prepared || (chip->chip_status & VX_STAT_IS_STALE))
+		return;
+	for (i = 0; i < nchunks; i++) {
+		err = vx_pcm_playback_transfer_chunk(chip, runtime, pipe,
+						     chip->ibl.size);
+		if (err < 0)
+			return;
+	}
+}
+
+/*
+ * update the playback position and call snd_pcm_period_elapsed() if necessary
+ * called from interrupt handler
+ */
+static void vx_pcm_playback_update(struct vx_core *chip,
+				   struct snd_pcm_substream *subs,
+				   struct vx_pipe *pipe)
+{
+	int err;
+	struct snd_pcm_runtime *runtime = subs->runtime;
+
+	if (pipe->running && ! (chip->chip_status & VX_STAT_IS_STALE)) {
+		err = vx_update_pipe_position(chip, runtime, pipe);
+		if (err < 0)
+			return;
+		if (pipe->transferred >= (int)runtime->period_size) {
+			pipe->transferred %= runtime->period_size;
+			snd_pcm_period_elapsed(subs);
+		}
+	}
+}
+
+/*
+ * vx_pcm_playback_trigger - trigger callback for playback
+ */
+static int vx_pcm_trigger(struct snd_pcm_substream *subs, int cmd)
+{
+	struct vx_core *chip = snd_pcm_substream_chip(subs);
+	struct vx_pipe *pipe = subs->runtime->private_data;
+	int err;
+
+	if (chip->chip_status & VX_STAT_IS_STALE)
+		return -EBUSY;
+		
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		if (! pipe->is_capture)
+			vx_pcm_playback_transfer(chip, subs, pipe, 2);
+		err = vx_start_stream(chip, pipe);
+		if (err < 0) {
+			pr_debug("vx: cannot start stream\n");
+			return err;
+		}
+		err = vx_toggle_pipe(chip, pipe, 1);
+		if (err < 0) {
+			pr_debug("vx: cannot start pipe\n");
+			vx_stop_stream(chip, pipe);
+			return err;
+		}
+		chip->pcm_running++;
+		pipe->running = 1;
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		vx_toggle_pipe(chip, pipe, 0);
+		vx_stop_pipe(chip, pipe);
+		vx_stop_stream(chip, pipe);
+		chip->pcm_running--;
+		pipe->running = 0;
+		break;
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		err = vx_toggle_pipe(chip, pipe, 0);
+		if (err < 0)
+			return err;
+		break;
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		err = vx_toggle_pipe(chip, pipe, 1);
+		if (err < 0)
+			return err;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/*
+ * vx_pcm_playback_pointer - pointer callback for playback
+ */
+static snd_pcm_uframes_t vx_pcm_playback_pointer(struct snd_pcm_substream *subs)
+{
+	struct snd_pcm_runtime *runtime = subs->runtime;
+	struct vx_pipe *pipe = runtime->private_data;
+	return pipe->position;
+}
+
+/*
+ * vx_pcm_prepare - prepare callback for playback and capture
+ */
+static int vx_pcm_prepare(struct snd_pcm_substream *subs)
+{
+	struct vx_core *chip = snd_pcm_substream_chip(subs);
+	struct snd_pcm_runtime *runtime = subs->runtime;
+	struct vx_pipe *pipe = runtime->private_data;
+	int err, data_mode;
+	// int max_size, nchunks;
+
+	if (chip->chip_status & VX_STAT_IS_STALE)
+		return -EBUSY;
+
+	data_mode = (chip->uer_bits & IEC958_AES0_NONAUDIO) != 0;
+	if (data_mode != pipe->data_mode && ! pipe->is_capture) {
+		/* IEC958 status (raw-mode) was changed */
+		/* we reopen the pipe */
+		struct vx_rmh rmh;
+		snd_printdd(KERN_DEBUG "reopen the pipe with data_mode = %d\n", data_mode);
+		vx_init_rmh(&rmh, CMD_FREE_PIPE);
+		vx_set_pipe_cmd_params(&rmh, 0, pipe->number, 0);
+		err = vx_send_msg(chip, &rmh);
+		if (err < 0)
+			return err;
+		vx_init_rmh(&rmh, CMD_RES_PIPE);
+		vx_set_pipe_cmd_params(&rmh, 0, pipe->number, pipe->channels);
+		if (data_mode)
+			rmh.Cmd[0] |= BIT_DATA_MODE;
+		err = vx_send_msg(chip, &rmh);
+		if (err < 0)
+			return err;
+		pipe->data_mode = data_mode;
+	}
+
+	if (chip->pcm_running && chip->freq != runtime->rate) {
+		snd_printk(KERN_ERR "vx: cannot set different clock %d "
+			   "from the current %d\n", runtime->rate, chip->freq);
+		return -EINVAL;
+	}
+	vx_set_clock(chip, runtime->rate);
+
+	err = vx_set_format(chip, pipe, runtime);
+	if (err < 0)
+		return err;
+
+	if (vx_is_pcmcia(chip)) {
+		pipe->align = 2; /* 16bit word */
+	} else {
+		pipe->align = 4; /* 32bit word */
+	}
+
+	pipe->buffer_bytes = frames_to_bytes(runtime, runtime->buffer_size);
+	pipe->period_bytes = frames_to_bytes(runtime, runtime->period_size);
+	pipe->hw_ptr = 0;
+
+	/* set the timestamp */
+	vx_update_pipe_position(chip, runtime, pipe);
+	/* clear again */
+	pipe->transferred = 0;
+	pipe->position = 0;
+
+	pipe->prepared = 1;
+
+	return 0;
+}
+
+
+/*
+ * operators for PCM playback
+ */
+static const struct snd_pcm_ops vx_pcm_playback_ops = {
+	.open =		vx_pcm_playback_open,
+	.close =	vx_pcm_playback_close,
+	.prepare =	vx_pcm_prepare,
+	.trigger =	vx_pcm_trigger,
+	.pointer =	vx_pcm_playback_pointer,
+};
+
+
+/*
+ * playback hw information
+ */
+
+static const struct snd_pcm_hardware vx_pcm_capture_hw = {
+	.info =			(SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED |
+				 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_MMAP_VALID /*|*/
+				 /*SNDRV_PCM_INFO_RESUME*/),
+	.formats =		(/*SNDRV_PCM_FMTBIT_U8 |*/
+				 SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_3LE),
+	.rates =		SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_8000_48000,
+	.rate_min =		5000,
+	.rate_max =		48000,
+	.channels_min =		1,
+	.channels_max =		2,
+	.buffer_bytes_max =	(128*1024),
+	.period_bytes_min =	126,
+	.period_bytes_max =	(128*1024),
+	.periods_min =		2,
+	.periods_max =		VX_MAX_PERIODS,
+	.fifo_size =		126,
+};
+
+
+/*
+ * vx_pcm_capture_open - open callback for capture
+ */
+static int vx_pcm_capture_open(struct snd_pcm_substream *subs)
+{
+	struct snd_pcm_runtime *runtime = subs->runtime;
+	struct vx_core *chip = snd_pcm_substream_chip(subs);
+	struct vx_pipe *pipe;
+	struct vx_pipe *pipe_out_monitoring = NULL;
+	unsigned int audio;
+	int err;
+
+	if (chip->chip_status & VX_STAT_IS_STALE)
+		return -EBUSY;
+
+	audio = subs->pcm->device * 2;
+	if (snd_BUG_ON(audio >= chip->audio_ins))
+		return -EINVAL;
+	err = vx_alloc_pipe(chip, 1, audio, 2, &pipe);
+	if (err < 0)
+		return err;
+	pipe->substream = subs;
+	chip->capture_pipes[audio] = pipe;
+
+	/* check if monitoring is needed */
+	if (chip->audio_monitor_active[audio]) {
+		pipe_out_monitoring = chip->playback_pipes[audio];
+		if (! pipe_out_monitoring) {
+			/* allocate a pipe */
+			err = vx_alloc_pipe(chip, 0, audio, 2, &pipe_out_monitoring);
+			if (err < 0)
+				return err;
+			chip->playback_pipes[audio] = pipe_out_monitoring;
+		}
+		pipe_out_monitoring->references++;
+		/* 
+		   if an output pipe is available, it's audios still may need to be 
+		   unmuted. hence we'll have to call a mixer entry point.
+		*/
+		vx_set_monitor_level(chip, audio, chip->audio_monitor[audio],
+				     chip->audio_monitor_active[audio]);
+		/* assuming stereo */
+		vx_set_monitor_level(chip, audio+1, chip->audio_monitor[audio+1],
+				     chip->audio_monitor_active[audio+1]); 
+	}
+
+	pipe->monitoring_pipe = pipe_out_monitoring; /* default value NULL */
+
+	runtime->hw = vx_pcm_capture_hw;
+	runtime->hw.period_bytes_min = chip->ibl.size;
+	runtime->private_data = pipe;
+
+	/* align to 4 bytes (otherwise will be problematic when 24bit is used) */ 
+	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 4);
+	snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 4);
+
+	return 0;
+}
+
+/*
+ * vx_pcm_capture_close - close callback for capture
+ */
+static int vx_pcm_capture_close(struct snd_pcm_substream *subs)
+{
+	struct vx_core *chip = snd_pcm_substream_chip(subs);
+	struct vx_pipe *pipe;
+	struct vx_pipe *pipe_out_monitoring;
+	
+	if (! subs->runtime->private_data)
+		return -EINVAL;
+	pipe = subs->runtime->private_data;
+	chip->capture_pipes[pipe->number] = NULL;
+
+	pipe_out_monitoring = pipe->monitoring_pipe;
+
+	/*
+	  if an output pipe is attached to this input, 
+	  check if it needs to be released.
+	*/
+	if (pipe_out_monitoring) {
+		if (--pipe_out_monitoring->references == 0) {
+			vx_free_pipe(chip, pipe_out_monitoring);
+			chip->playback_pipes[pipe->number] = NULL;
+			pipe->monitoring_pipe = NULL;
+		}
+	}
+	
+	vx_free_pipe(chip, pipe);
+	return 0;
+}
+
+
+
+#define DMA_READ_ALIGN	6	/* hardware alignment for read */
+
+/*
+ * vx_pcm_capture_update - update the capture buffer
+ */
+static void vx_pcm_capture_update(struct vx_core *chip, struct snd_pcm_substream *subs,
+				  struct vx_pipe *pipe)
+{
+	int size, space, count;
+	struct snd_pcm_runtime *runtime = subs->runtime;
+
+	if (!pipe->running || (chip->chip_status & VX_STAT_IS_STALE))
+		return;
+
+	size = runtime->buffer_size - snd_pcm_capture_avail(runtime);
+	if (! size)
+		return;
+	size = frames_to_bytes(runtime, size);
+	space = vx_query_hbuffer_size(chip, pipe);
+	if (space < 0)
+		goto _error;
+	if (size > space)
+		size = space;
+	size = (size / 3) * 3; /* align to 3 bytes */
+	if (size < DMA_READ_ALIGN)
+		goto _error;
+
+	/* keep the last 6 bytes, they will be read after disconnection */
+	count = size - DMA_READ_ALIGN;
+	/* read bytes until the current pointer reaches to the aligned position
+	 * for word-transfer
+	 */
+	while (count > 0) {
+		if ((pipe->hw_ptr % pipe->align) == 0)
+			break;
+		if (vx_wait_for_rx_full(chip) < 0)
+			goto _error;
+		vx_pcm_read_per_bytes(chip, runtime, pipe);
+		count -= 3;
+	}
+	if (count > 0) {
+		/* ok, let's accelerate! */
+		int align = pipe->align * 3;
+		space = (count / align) * align;
+		if (space > 0) {
+			vx_pseudo_dma_read(chip, runtime, pipe, space);
+			count -= space;
+		}
+	}
+	/* read the rest of bytes */
+	while (count > 0) {
+		if (vx_wait_for_rx_full(chip) < 0)
+			goto _error;
+		vx_pcm_read_per_bytes(chip, runtime, pipe);
+		count -= 3;
+	}
+	/* disconnect the host, SIZE_HBUF command always switches to the stream mode */
+	vx_send_rih(chip, IRQ_CONNECT_STREAM_NEXT);
+	/* read the last pending 6 bytes */
+	count = DMA_READ_ALIGN;
+	while (count > 0) {
+		vx_pcm_read_per_bytes(chip, runtime, pipe);
+		count -= 3;
+	}
+	/* update the position */
+	pipe->transferred += size;
+	if (pipe->transferred >= pipe->period_bytes) {
+		pipe->transferred %= pipe->period_bytes;
+		snd_pcm_period_elapsed(subs);
+	}
+	return;
+
+ _error:
+	/* disconnect the host, SIZE_HBUF command always switches to the stream mode */
+	vx_send_rih(chip, IRQ_CONNECT_STREAM_NEXT);
+	return;
+}
+
+/*
+ * vx_pcm_capture_pointer - pointer callback for capture
+ */
+static snd_pcm_uframes_t vx_pcm_capture_pointer(struct snd_pcm_substream *subs)
+{
+	struct snd_pcm_runtime *runtime = subs->runtime;
+	struct vx_pipe *pipe = runtime->private_data;
+	return bytes_to_frames(runtime, pipe->hw_ptr);
+}
+
+/*
+ * operators for PCM capture
+ */
+static const struct snd_pcm_ops vx_pcm_capture_ops = {
+	.open =		vx_pcm_capture_open,
+	.close =	vx_pcm_capture_close,
+	.prepare =	vx_pcm_prepare,
+	.trigger =	vx_pcm_trigger,
+	.pointer =	vx_pcm_capture_pointer,
+};
+
+
+/*
+ * interrupt handler for pcm streams
+ */
+void vx_pcm_update_intr(struct vx_core *chip, unsigned int events)
+{
+	unsigned int i;
+	struct vx_pipe *pipe;
+
+#define EVENT_MASK	(END_OF_BUFFER_EVENTS_PENDING|ASYNC_EVENTS_PENDING)
+
+	if (events & EVENT_MASK) {
+		vx_init_rmh(&chip->irq_rmh, CMD_ASYNC);
+		if (events & ASYNC_EVENTS_PENDING)
+			chip->irq_rmh.Cmd[0] |= 0x00000001;	/* SEL_ASYNC_EVENTS */
+		if (events & END_OF_BUFFER_EVENTS_PENDING)
+			chip->irq_rmh.Cmd[0] |= 0x00000002;	/* SEL_END_OF_BUF_EVENTS */
+
+		if (vx_send_msg(chip, &chip->irq_rmh) < 0) {
+			snd_printdd(KERN_ERR "msg send error!!\n");
+			return;
+		}
+
+		i = 1;
+		while (i < chip->irq_rmh.LgStat) {
+			int p, buf, capture, eob;
+			p = chip->irq_rmh.Stat[i] & MASK_FIRST_FIELD;
+			capture = (chip->irq_rmh.Stat[i] & 0x400000) ? 1 : 0;
+			eob = (chip->irq_rmh.Stat[i] & 0x800000) ? 1 : 0;
+			i++;
+			if (events & ASYNC_EVENTS_PENDING)
+				i++;
+			buf = 1; /* force to transfer */
+			if (events & END_OF_BUFFER_EVENTS_PENDING) {
+				if (eob)
+					buf = chip->irq_rmh.Stat[i];
+				i++;
+			}
+			if (capture)
+				continue;
+			if (snd_BUG_ON(p < 0 || p >= chip->audio_outs))
+				continue;
+			pipe = chip->playback_pipes[p];
+			if (pipe && pipe->substream) {
+				vx_pcm_playback_update(chip, pipe->substream, pipe);
+				vx_pcm_playback_transfer(chip, pipe->substream, pipe, buf);
+			}
+		}
+	}
+
+	/* update the capture pcm pointers as frequently as possible */
+	for (i = 0; i < chip->audio_ins; i++) {
+		pipe = chip->capture_pipes[i];
+		if (pipe && pipe->substream)
+			vx_pcm_capture_update(chip, pipe->substream, pipe);
+	}
+}
+
+
+/*
+ * vx_init_audio_io - check the available audio i/o and allocate pipe arrays
+ */
+static int vx_init_audio_io(struct vx_core *chip)
+{
+	struct vx_rmh rmh;
+	int preferred;
+
+	vx_init_rmh(&rmh, CMD_SUPPORTED);
+	if (vx_send_msg(chip, &rmh) < 0) {
+		snd_printk(KERN_ERR "vx: cannot get the supported audio data\n");
+		return -ENXIO;
+	}
+
+	chip->audio_outs = rmh.Stat[0] & MASK_FIRST_FIELD;
+	chip->audio_ins = (rmh.Stat[0] >> (FIELD_SIZE*2)) & MASK_FIRST_FIELD;
+	chip->audio_info = rmh.Stat[1];
+
+	/* allocate pipes */
+	chip->playback_pipes = kcalloc(chip->audio_outs, sizeof(struct vx_pipe *), GFP_KERNEL);
+	if (!chip->playback_pipes)
+		return -ENOMEM;
+	chip->capture_pipes = kcalloc(chip->audio_ins, sizeof(struct vx_pipe *), GFP_KERNEL);
+	if (!chip->capture_pipes) {
+		kfree(chip->playback_pipes);
+		return -ENOMEM;
+	}
+
+	preferred = chip->ibl.size;
+	chip->ibl.size = 0;
+	vx_set_ibl(chip, &chip->ibl); /* query the info */
+	if (preferred > 0) {
+		chip->ibl.size = roundup(preferred, chip->ibl.granularity);
+		if (chip->ibl.size > chip->ibl.max_size)
+			chip->ibl.size = chip->ibl.max_size;
+	} else
+		chip->ibl.size = chip->ibl.min_size; /* set to the minimum */
+	vx_set_ibl(chip, &chip->ibl);
+
+	return 0;
+}
+
+
+/*
+ * free callback for pcm
+ */
+static void snd_vx_pcm_free(struct snd_pcm *pcm)
+{
+	struct vx_core *chip = pcm->private_data;
+	chip->pcm[pcm->device] = NULL;
+	kfree(chip->playback_pipes);
+	chip->playback_pipes = NULL;
+	kfree(chip->capture_pipes);
+	chip->capture_pipes = NULL;
+}
+
+/*
+ * snd_vx_pcm_new - create and initialize a pcm
+ */
+int snd_vx_pcm_new(struct vx_core *chip)
+{
+	struct snd_pcm *pcm;
+	unsigned int i;
+	int err;
+
+	err = vx_init_audio_io(chip);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i < chip->hw->num_codecs; i++) {
+		unsigned int outs, ins;
+		outs = chip->audio_outs > i * 2 ? 1 : 0;
+		ins = chip->audio_ins > i * 2 ? 1 : 0;
+		if (! outs && ! ins)
+			break;
+		err = snd_pcm_new(chip->card, "VX PCM", i,
+				  outs, ins, &pcm);
+		if (err < 0)
+			return err;
+		if (outs)
+			snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &vx_pcm_playback_ops);
+		if (ins)
+			snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &vx_pcm_capture_ops);
+		snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC,
+					       NULL, 0, 0);
+
+		pcm->private_data = chip;
+		pcm->private_free = snd_vx_pcm_free;
+		pcm->info_flags = 0;
+		pcm->nonatomic = true;
+		strcpy(pcm->name, chip->card->shortname);
+		chip->pcm[i] = pcm;
+	}
+
+	return 0;
+}