Quelle  asihpi.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  Asihpi soundcard
 *  Copyright (c) by AudioScience Inc <support@audioscience.com>
 *
 *  The following is not a condition of use, merely a request:
 *  If you modify this program, particularly if you fix errors, AudioScience Inc
 *  would appreciate it if you grant us the right to use those modifications
 *  for any purpose including commercial applications.
 */

#include "hpi_internal.h"
#include "hpi_version.h"
#include "hpimsginit.h"
#include "hpioctl.h"
#include "hpicmn.h"

#include <linux/pci.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/wait.h>
#include <linux/module.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/info.h>
#include <sound/initval.h>
#include <sound/tlv.h>
#include <sound/hwdep.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("AudioScience inc. ");
MODULE_DESCRIPTION("AudioScience ALSA ASI5xxx ASI6xxx ASI87xx ASI89xx "
   HPI_VER_STRING);

#ifdef ASIHPI_VERBOSE_DEBUG
#define asihpi_dbg(format, args...) pr_debug(format, ##args)
#else
#define asihpi_dbg(format, args...) do { } while (0)
#endif

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* index 0-MAX */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */
static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;
static bool enable_hpi_hwdep = 1;

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "ALSA index value for AudioScience soundcard.");

module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ALSA ID string for AudioScience soundcard.");

module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "ALSA enable AudioScience soundcard.");

module_param(enable_hpi_hwdep, bool, 0644);
MODULE_PARM_DESC(enable_hpi_hwdep,
  "ALSA enable HPI hwdep for AudioScience soundcard ");

/* identify driver */
#ifdef KERNEL_ALSA_BUILD
static char *build_info = "Built using headers from kernel source";
module_param(build_info, charp, 0444);
MODULE_PARM_DESC(build_info, "Built using headers from kernel source");
#else
static char *build_info = "Built within ALSA source";
module_param(build_info, charp, 0444);
MODULE_PARM_DESC(build_info, "Built within ALSA source");
#endif

/* set to 1 to dump every control from adapter to log */
static const int mixer_dump;

#define DEFAULT_SAMPLERATE 44100
static int adapter_fs = DEFAULT_SAMPLERATE;

/* defaults */
#define PERIODS_MIN 2
#define PERIOD_BYTES_MIN  2048
#define BUFFER_BYTES_MAX (512 * 1024)

#define MAX_CLOCKSOURCES (HPI_SAMPLECLOCK_SOURCE_LAST + 1 + 7)

struct clk_source {
 int source;
 int index;
 const char *name;
};

struct clk_cache {
 int count;
 int has_local;
 struct clk_source s[MAX_CLOCKSOURCES];
};

/* Per card data */
struct snd_card_asihpi {
 struct snd_card *card;
 struct pci_dev *pci;
 struct hpi_adapter *hpi;

 /* In low latency mode there is only one stream, a pointer to its
 * private data is stored here on trigger and cleared on stop.
 * The interrupt handler uses it as a parameter when calling
 * snd_card_asihpi_timer_function().
 */
 struct snd_card_asihpi_pcm *llmode_streampriv;
 void (*pcm_start)(struct snd_pcm_substream *substream);
 void (*pcm_stop)(struct snd_pcm_substream *substream);

 u32 h_mixer;
 struct clk_cache cc;

 u16 can_dma;
 u16 support_grouping;
 u16 support_mrx;
 u16 update_interval_frames;
 u16 in_max_chans;
 u16 out_max_chans;
 u16 in_min_chans;
 u16 out_min_chans;
};

/* Per stream data */
struct snd_card_asihpi_pcm {
 struct timer_list timer;
 unsigned int respawn_timer;
 unsigned int hpi_buffer_attached;
 unsigned int buffer_bytes;
 unsigned int period_bytes;
 unsigned int bytes_per_sec;
 unsigned int pcm_buf_host_rw_ofs; /* Host R/W pos */
 unsigned int pcm_buf_dma_ofs; /* DMA R/W offset in buffer */
 unsigned int pcm_buf_elapsed_dma_ofs; /* DMA R/W offset in buffer */
 unsigned int drained_count;
 struct snd_pcm_substream *substream;
 u32 h_stream;
 struct hpi_format format;
};

/* universal stream verbs work with out or in stream handles */

/* Functions to allow driver to give a buffer to HPI for busmastering */

static u16 hpi_stream_host_buffer_attach(
 u32 h_stream,   /* handle to outstream. */
 u32 size_in_bytes, /* size in bytes of bus mastering buffer */
 u32 pci_address
)
{
 struct hpi_message hm;
 struct hpi_response hr;
 unsigned int obj = hpi_handle_object(h_stream);

 if (!h_stream)
  return HPI_ERROR_INVALID_OBJ;
 hpi_init_message_response(&hm, &hr, obj,
   obj == HPI_OBJ_OSTREAM ?
    HPI_OSTREAM_HOSTBUFFER_ALLOC :
    HPI_ISTREAM_HOSTBUFFER_ALLOC);

 hpi_handle_to_indexes(h_stream, &hm.adapter_index,
    &hm.obj_index);

 hm.u.d.u.buffer.buffer_size = size_in_bytes;
 hm.u.d.u.buffer.pci_address = pci_address;
 hm.u.d.u.buffer.command = HPI_BUFFER_CMD_INTERNAL_GRANTADAPTER;
 hpi_send_recv(&hm, &hr);
 return hr.error;
}

static u16 hpi_stream_host_buffer_detach(u32  h_stream)
{
 struct hpi_message hm;
 struct hpi_response hr;
 unsigned int obj = hpi_handle_object(h_stream);

 if (!h_stream)
  return HPI_ERROR_INVALID_OBJ;

 hpi_init_message_response(&hm, &hr,  obj,
   obj == HPI_OBJ_OSTREAM ?
    HPI_OSTREAM_HOSTBUFFER_FREE :
    HPI_ISTREAM_HOSTBUFFER_FREE);

 hpi_handle_to_indexes(h_stream, &hm.adapter_index,
    &hm.obj_index);
 hm.u.d.u.buffer.command = HPI_BUFFER_CMD_INTERNAL_REVOKEADAPTER;
 hpi_send_recv(&hm, &hr);
 return hr.error;
}

static inline u16 hpi_stream_start(u32 h_stream)
{
 if (hpi_handle_object(h_stream) ==  HPI_OBJ_OSTREAM)
  return hpi_outstream_start(h_stream);
 else
  return hpi_instream_start(h_stream);
}

static inline u16 hpi_stream_stop(u32 h_stream)
{
 if (hpi_handle_object(h_stream) ==  HPI_OBJ_OSTREAM)
  return hpi_outstream_stop(h_stream);
 else
  return hpi_instream_stop(h_stream);
}

static inline u16 hpi_stream_get_info_ex(
    u32 h_stream,
    u16        *pw_state,
    u32        *pbuffer_size,
    u32        *pdata_in_buffer,
    u32        *psample_count,
    u32        *pauxiliary_data
)
{
 u16 e;
 if (hpi_handle_object(h_stream)  ==  HPI_OBJ_OSTREAM)
  e = hpi_outstream_get_info_ex(h_stream, pw_state,
     pbuffer_size, pdata_in_buffer,
     psample_count, pauxiliary_data);
 else
  e = hpi_instream_get_info_ex(h_stream, pw_state,
     pbuffer_size, pdata_in_buffer,
     psample_count, pauxiliary_data);
 return e;
}

static inline u16 hpi_stream_group_add(
     u32 h_master,
     u32 h_stream)
{
 if (hpi_handle_object(h_master) ==  HPI_OBJ_OSTREAM)
  return hpi_outstream_group_add(h_master, h_stream);
 else
  return hpi_instream_group_add(h_master, h_stream);
}

static inline u16 hpi_stream_group_reset(u32 h_stream)
{
 if (hpi_handle_object(h_stream) ==  HPI_OBJ_OSTREAM)
  return hpi_outstream_group_reset(h_stream);
 else
  return hpi_instream_group_reset(h_stream);
}

static u16 handle_error(u16 err, int line, char *filename)
{
 if (err)
  pr_warn("in file %s, line %d: HPI error %d\n",
   filename, line, err);
 return err;
}

#define hpi_handle_error(x)  handle_error(x, __LINE__, __FILE__)

/***************************** GENERAL PCM ****************/

static void print_hwparams(struct snd_pcm_substream *substream,
    struct snd_pcm_hw_params *p)
{
 struct device *dev = substream->pcm->card->dev;
 char name[16];

 snd_pcm_debug_name(substream, name, sizeof(name));
 dev_dbg(dev, "%s HWPARAMS\n", name);
 dev_dbg(dev, " samplerate=%dHz channels=%d format=%d subformat=%d\n",
  params_rate(p), params_channels(p),
  params_format(p), params_subformat(p));
 dev_dbg(dev, " buffer=%dB period=%dB period_size=%dB periods=%d\n",
  params_buffer_bytes(p), params_period_bytes(p),
  params_period_size(p), params_periods(p));
 dev_dbg(dev, " buffer_size=%d access=%d data_rate=%dB/s\n",
  params_buffer_size(p), params_access(p),
  params_rate(p) * params_channels(p) *
  snd_pcm_format_width(params_format(p)) / 8);
}

#define INVALID_FORMAT (__force snd_pcm_format_t)(-1)

static const snd_pcm_format_t hpi_to_alsa_formats[] = {
 INVALID_FORMAT,  /* INVALID */
 SNDRV_PCM_FORMAT_U8, /* HPI_FORMAT_PCM8_UNSIGNED        1 */
 SNDRV_PCM_FORMAT_S16, /* HPI_FORMAT_PCM16_SIGNED         2 */
 INVALID_FORMAT,  /* HPI_FORMAT_MPEG_L1              3 */
 SNDRV_PCM_FORMAT_MPEG, /* HPI_FORMAT_MPEG_L2              4 */
 SNDRV_PCM_FORMAT_MPEG, /* HPI_FORMAT_MPEG_L3              5 */
 INVALID_FORMAT,  /* HPI_FORMAT_DOLBY_AC2            6 */
 INVALID_FORMAT,  /* HPI_FORMAT_DOLBY_AC3            7 */
 SNDRV_PCM_FORMAT_S16_BE,/* HPI_FORMAT_PCM16_BIGENDIAN      8 */
 INVALID_FORMAT,  /* HPI_FORMAT_AA_TAGIT1_HITS       9 */
 INVALID_FORMAT,  /* HPI_FORMAT_AA_TAGIT1_INSERTS   10 */
 SNDRV_PCM_FORMAT_S32, /* HPI_FORMAT_PCM32_SIGNED        11 */
 INVALID_FORMAT,  /* HPI_FORMAT_RAW_BITSTREAM       12 */
 INVALID_FORMAT,  /* HPI_FORMAT_AA_TAGIT1_HITS_EX1  13 */
 SNDRV_PCM_FORMAT_FLOAT, /* HPI_FORMAT_PCM32_FLOAT         14 */
#if 1
 /* ALSA can't handle 3 byte sample size together with power-of-2
 *  constraint on buffer_bytes, so disable this format
 */
 INVALID_FORMAT
#else
 /* SNDRV_PCM_FORMAT_S24_3LE */ /* HPI_FORMAT_PCM24_SIGNED 15 */
#endif
};


static int snd_card_asihpi_format_alsa2hpi(struct snd_card_asihpi *asihpi,
        snd_pcm_format_t alsa_format,
        u16 *hpi_format)
{
 u16 format;

 for (format = HPI_FORMAT_PCM8_UNSIGNED;
      format <= HPI_FORMAT_PCM24_SIGNED; format++) {
  if (hpi_to_alsa_formats[format] == alsa_format) {
   *hpi_format = format;
   return 0;
  }
 }

 dev_dbg(asihpi->card->dev, "failed match for alsa format %d\n",
  alsa_format);
 *hpi_format = 0;
 return -EINVAL;
}

static void snd_card_asihpi_pcm_samplerates(struct snd_card_asihpi *asihpi,
      struct snd_pcm_hardware *pcmhw)
{
 u16 err;
 u32 h_control;
 u32 sample_rate;
 int idx;
 unsigned int rate_min = 200000;
 unsigned int rate_max = 0;
 unsigned int rates = 0;

 if (asihpi->support_mrx) {
  rates |= SNDRV_PCM_RATE_CONTINUOUS;
  rates |= SNDRV_PCM_RATE_8000_96000;
  rate_min = 8000;
  rate_max = 100000;
 } else {
  /* on cards without SRC,
   valid rates are determined by sampleclock */
  err = hpi_mixer_get_control(asihpi->h_mixer,
       HPI_SOURCENODE_CLOCK_SOURCE, 0, 0, 0,
       HPI_CONTROL_SAMPLECLOCK, &h_control);
  if (err) {
   dev_err(&asihpi->pci->dev,
    "No local sampleclock, err %d\n", err);
  }

  for (idx = -1; idx < 100; idx++) {
   if (idx == -1) {
    if (hpi_sample_clock_get_sample_rate(h_control,
        &sample_rate))
     continue;
   } else if (hpi_sample_clock_query_local_rate(h_control,
       idx, &sample_rate)) {
    break;
   }

   rate_min = min(rate_min, sample_rate);
   rate_max = max(rate_max, sample_rate);

   switch (sample_rate) {
   case 5512:
    rates |= SNDRV_PCM_RATE_5512;
    break;
   case 8000:
    rates |= SNDRV_PCM_RATE_8000;
    break;
   case 11025:
    rates |= SNDRV_PCM_RATE_11025;
    break;
   case 16000:
    rates |= SNDRV_PCM_RATE_16000;
    break;
   case 22050:
    rates |= SNDRV_PCM_RATE_22050;
    break;
   case 32000:
    rates |= SNDRV_PCM_RATE_32000;
    break;
   case 44100:
    rates |= SNDRV_PCM_RATE_44100;
    break;
   case 48000:
    rates |= SNDRV_PCM_RATE_48000;
    break;
   case 64000:
    rates |= SNDRV_PCM_RATE_64000;
    break;
   case 88200:
    rates |= SNDRV_PCM_RATE_88200;
    break;
   case 96000:
    rates |= SNDRV_PCM_RATE_96000;
    break;
   case 176400:
    rates |= SNDRV_PCM_RATE_176400;
    break;
   case 192000:
    rates |= SNDRV_PCM_RATE_192000;
    break;
   default: /* some other rate */
    rates |= SNDRV_PCM_RATE_KNOT;
   }
  }
 }

 pcmhw->rates = rates;
 pcmhw->rate_min = rate_min;
 pcmhw->rate_max = rate_max;
}

static int snd_card_asihpi_pcm_hw_params(struct snd_pcm_substream *substream,
      struct snd_pcm_hw_params *params)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;
 struct snd_card_asihpi *card = snd_pcm_substream_chip(substream);
 int err;
 u16 format;
 int width;
 unsigned int bytes_per_sec;

 print_hwparams(substream, params);
 err = snd_card_asihpi_format_alsa2hpi(card, params_format(params), &format);
 if (err)
  return err;

 hpi_handle_error(hpi_format_create(&dpcm->format,
   params_channels(params),
   format, params_rate(params), 0, 0));

 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
  if (hpi_instream_reset(dpcm->h_stream) != 0)
   return -EINVAL;

  if (hpi_instream_set_format(
   dpcm->h_stream, &dpcm->format) != 0)
   return -EINVAL;
 }

 dpcm->hpi_buffer_attached = 0;
 if (card->can_dma) {
  err = hpi_stream_host_buffer_attach(dpcm->h_stream,
   params_buffer_bytes(params),  runtime->dma_addr);
  if (err == 0) {
   dev_dbg(card->card->dev,
    "stream_host_buffer_attach success %u %lu\n",
    params_buffer_bytes(params),
    (unsigned long)runtime->dma_addr);
  } else {
   dev_dbg(card->card->dev,
    "stream_host_buffer_attach error %d\n", err);
   return -ENOMEM;
  }

  hpi_stream_get_info_ex(dpcm->h_stream, NULL,
    &dpcm->hpi_buffer_attached, NULL, NULL, NULL);
 }
 bytes_per_sec = params_rate(params) * params_channels(params);
 width = snd_pcm_format_width(params_format(params));
 bytes_per_sec *= width;
 bytes_per_sec /= 8;
 if (width < 0 || bytes_per_sec == 0)
  return -EINVAL;

 dpcm->bytes_per_sec = bytes_per_sec;
 dpcm->buffer_bytes = params_buffer_bytes(params);
 dpcm->period_bytes = params_period_bytes(params);

 return 0;
}

static int
snd_card_asihpi_hw_free(struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;
 if (dpcm->hpi_buffer_attached)
  hpi_stream_host_buffer_detach(dpcm->h_stream);

 return 0;
}

static void snd_card_asihpi_runtime_free(struct snd_pcm_runtime *runtime)
{
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;
 kfree(dpcm);
}

static void snd_card_asihpi_pcm_timer_start(struct snd_pcm_substream *
         substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;
 int expiry;

 expiry = HZ / 200;

 expiry = max(expiry, 1); /* don't let it be zero! */
 mod_timer(&dpcm->timer, jiffies + expiry);
 dpcm->respawn_timer = 1;
}

static void snd_card_asihpi_pcm_timer_stop(struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;

 dpcm->respawn_timer = 0;
 timer_delete(&dpcm->timer);
}

static void snd_card_asihpi_pcm_int_start(struct snd_pcm_substream *substream)
{
 struct snd_card_asihpi_pcm *dpcm;
 struct snd_card_asihpi *card;

 dpcm = (struct snd_card_asihpi_pcm *)substream->runtime->private_data;
 card = snd_pcm_substream_chip(substream);

 WARN_ON(in_interrupt());
 card->llmode_streampriv = dpcm;

 hpi_handle_error(hpi_adapter_set_property(card->hpi->adapter->index,
  HPI_ADAPTER_PROPERTY_IRQ_RATE,
  card->update_interval_frames, 0));
}

static void snd_card_asihpi_pcm_int_stop(struct snd_pcm_substream *substream)
{
 struct snd_card_asihpi *card;

 card = snd_pcm_substream_chip(substream);

 hpi_handle_error(hpi_adapter_set_property(card->hpi->adapter->index,
  HPI_ADAPTER_PROPERTY_IRQ_RATE, 0, 0));

 card->llmode_streampriv = NULL;
}

static int snd_card_asihpi_trigger(struct snd_pcm_substream *substream,
        int cmd)
{
 struct snd_card_asihpi_pcm *dpcm = substream->runtime->private_data;
 struct snd_card_asihpi *card = snd_pcm_substream_chip(substream);
 struct snd_pcm_substream *s;
 u16 e;
 char name[16];

 snd_pcm_debug_name(substream, name, sizeof(name));

 switch (cmd) {
 case SNDRV_PCM_TRIGGER_START:
  dev_dbg(card->card->dev, "%s trigger start\n", name);
  snd_pcm_group_for_each_entry(s, substream) {
   struct snd_pcm_runtime *runtime = s->runtime;
   struct snd_card_asihpi_pcm *ds = runtime->private_data;

   if (snd_pcm_substream_chip(s) != card)
    continue;

   /* don't link Cap and Play */
   if (substream->stream != s->stream)
    continue;

   ds->drained_count = 0;
   if (s->stream == SNDRV_PCM_STREAM_PLAYBACK) {
    /* How do I know how much valid data is present
* in buffer? Must be at least one period!
* Guessing 2 periods, but if
* buffer is bigger it may contain even more
* data??
*/
    unsigned int preload = ds->period_bytes * 1;
    asihpi_dbg("%d preload %d\n", s->number, preload);
    hpi_handle_error(hpi_outstream_write_buf(
      ds->h_stream,
      &runtime->dma_area[0],
      preload,
      &ds->format));
    ds->pcm_buf_host_rw_ofs = preload;
   }

   if (card->support_grouping) {
    dev_dbg(card->card->dev, "%d group\n", s->number);
    e = hpi_stream_group_add(
     dpcm->h_stream,
     ds->h_stream);
    if (!e) {
     snd_pcm_trigger_done(s, substream);
    } else {
     hpi_handle_error(e);
     break;
    }
   } else
    break;
  }
  /* start the master stream */
  card->pcm_start(substream);
  if ((substream->stream == SNDRV_PCM_STREAM_CAPTURE) ||
   !card->can_dma)
   hpi_handle_error(hpi_stream_start(dpcm->h_stream));
  break;

 case SNDRV_PCM_TRIGGER_STOP:
  dev_dbg(card->card->dev, "%s trigger stop\n", name);
  card->pcm_stop(substream);
  snd_pcm_group_for_each_entry(s, substream) {
   if (snd_pcm_substream_chip(s) != card)
    continue;
   /* don't link Cap and Play */
   if (substream->stream != s->stream)
    continue;

   /*? workaround linked streams don't
transition to SETUP 20070706*/
   __snd_pcm_set_state(s->runtime, SNDRV_PCM_STATE_SETUP);

   if (card->support_grouping) {
    dev_dbg(card->card->dev, "%d group\n", s->number);
    snd_pcm_trigger_done(s, substream);
   } else
    break;
  }

  /* _prepare and _hwparams reset the stream */
  hpi_handle_error(hpi_stream_stop(dpcm->h_stream));
  if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
   hpi_handle_error(
    hpi_outstream_reset(dpcm->h_stream));

  if (card->support_grouping)
   hpi_handle_error(hpi_stream_group_reset(dpcm->h_stream));
  break;

 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
  dev_dbg(card->card->dev, "%s trigger pause release\n", name);
  card->pcm_start(substream);
  hpi_handle_error(hpi_stream_start(dpcm->h_stream));
  break;
 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
  dev_dbg(card->card->dev, "%s trigger pause push\n", name);
  card->pcm_stop(substream);
  hpi_handle_error(hpi_stream_stop(dpcm->h_stream));
  break;
 default:
  dev_dbg(card->card->dev, "\tINVALID\n");
  return -EINVAL;
 }

 return 0;
}

/*algorithm outline
 Without linking degenerates to getting single stream pos etc
 Without mmap 2nd loop degenerates to snd_pcm_period_elapsed
*/
/*
pcm_buf_dma_ofs=get_buf_pos(s);
for_each_linked_stream(s) {
pcm_buf_dma_ofs=get_buf_pos(s);
min_buf_pos = modulo_min(min_buf_pos, pcm_buf_dma_ofs, buffer_bytes)
new_data = min(new_data, calc_new_data(pcm_buf_dma_ofs,irq_pos)
}
timer.expires = jiffies + predict_next_period_ready(min_buf_pos);
for_each_linked_stream(s) {
s->pcm_buf_dma_ofs = min_buf_pos;
if (new_data > period_bytes) {
if (mmap) {
irq_pos = (irq_pos + period_bytes) % buffer_bytes;
if (playback) {
write(period_bytes);
} else {
read(period_bytes);
}
}
snd_pcm_period_elapsed(s);
}
}
*/

/** Minimum of 2 modulo values.  Works correctly when the difference between
* the values is less than half the modulus
*/
static inline unsigned int modulo_min(unsigned int a, unsigned int b,
     unsigned long int modulus)
{
 unsigned int result;
 if (((a-b) % modulus) < (modulus/2))
  result = b;
 else
  result = a;

 return result;
}

/** Timer function, equivalent to interrupt service routine for cards
*/
static void snd_card_asihpi_timer_function(struct timer_list *t)
{
 struct snd_card_asihpi_pcm *dpcm = timer_container_of(dpcm, t, timer);
 struct snd_pcm_substream *substream = dpcm->substream;
 struct snd_card_asihpi *card = snd_pcm_substream_chip(substream);
 struct snd_pcm_runtime *runtime;
 struct snd_pcm_substream *s;
 unsigned int newdata = 0;
 unsigned int pcm_buf_dma_ofs, min_buf_pos = 0;
 unsigned int remdata, xfercount, next_jiffies;
 int first = 1;
 u16 state;
 u32 buffer_size, bytes_avail, samples_played, on_card_bytes;
 char name[16];


 snd_pcm_debug_name(substream, name, sizeof(name));

 /* find minimum newdata and buffer pos in group */
 snd_pcm_group_for_each_entry(s, substream) {
  struct snd_card_asihpi_pcm *ds = s->runtime->private_data;
  runtime = s->runtime;

  if (snd_pcm_substream_chip(s) != card)
   continue;

  /* don't link Cap and Play */
  if (substream->stream != s->stream)
   continue;

  hpi_handle_error(hpi_stream_get_info_ex(
     ds->h_stream, &state,
     &buffer_size, &bytes_avail,
     &samples_played, &on_card_bytes));

  /* number of bytes in on-card buffer */
  runtime->delay = on_card_bytes;

  if (!card->can_dma)
   on_card_bytes = bytes_avail;

  if (s->stream == SNDRV_PCM_STREAM_PLAYBACK) {
   pcm_buf_dma_ofs = ds->pcm_buf_host_rw_ofs - bytes_avail;
   if (state == HPI_STATE_STOPPED) {
    if (bytes_avail == 0) {
     hpi_handle_error(hpi_stream_start(ds->h_stream));
     dev_dbg(card->card->dev,
      "P%d start\n", s->number);
     ds->drained_count = 0;
    }
   } else if (state == HPI_STATE_DRAINED) {
    dev_dbg(card->card->dev,
     "P%d drained\n", s->number);
    ds->drained_count++;
    if (ds->drained_count > 20) {
     snd_pcm_stop_xrun(s);
     continue;
    }
   } else {
    ds->drained_count = 0;
   }
  } else
   pcm_buf_dma_ofs = bytes_avail + ds->pcm_buf_host_rw_ofs;

  if (first) {
   /* can't statically init min when wrap is involved */
   min_buf_pos = pcm_buf_dma_ofs;
   newdata = (pcm_buf_dma_ofs - ds->pcm_buf_elapsed_dma_ofs) % ds->buffer_bytes;
   first = 0;
  } else {
   min_buf_pos =
    modulo_min(min_buf_pos, pcm_buf_dma_ofs, UINT_MAX+1L);
   newdata = min(
    (pcm_buf_dma_ofs - ds->pcm_buf_elapsed_dma_ofs) % ds->buffer_bytes,
    newdata);
  }

  asihpi_dbg(
   "timer1, %s, %d, S=%d, elap=%d, rw=%d, dsp=%d, left=%d, aux=%d, space=%d, hw_ptr=%ld, appl_ptr=%ld\n",
   name, s->number, state,
   ds->pcm_buf_elapsed_dma_ofs,
   ds->pcm_buf_host_rw_ofs,
   pcm_buf_dma_ofs,
   (int)bytes_avail,

   (int)on_card_bytes,
   buffer_size-bytes_avail,
   (unsigned long)frames_to_bytes(runtime,
      runtime->status->hw_ptr),
   (unsigned long)frames_to_bytes(runtime,
      runtime->control->appl_ptr)
  );
 }
 pcm_buf_dma_ofs = min_buf_pos;

 remdata = newdata % dpcm->period_bytes;
 xfercount = newdata - remdata; /* a multiple of period_bytes */
 /* come back when on_card_bytes has decreased enough to allow
   write to happen, or when data has been consumed to make another
   period
*/
 if (xfercount && (on_card_bytes  > dpcm->period_bytes))
  next_jiffies = ((on_card_bytes - dpcm->period_bytes) * HZ / dpcm->bytes_per_sec);
 else
  next_jiffies = ((dpcm->period_bytes - remdata) * HZ / dpcm->bytes_per_sec);

 next_jiffies = max(next_jiffies, 1U);
 dpcm->timer.expires = jiffies + next_jiffies;
 asihpi_dbg("timer2, jif=%d, buf_pos=%d, newdata=%d, xfer=%d\n",
   next_jiffies, pcm_buf_dma_ofs, newdata, xfercount);

 snd_pcm_group_for_each_entry(s, substream) {
  struct snd_card_asihpi_pcm *ds = s->runtime->private_data;

  /* don't link Cap and Play */
  if (substream->stream != s->stream)
   continue;

  /* Store dma offset for use by pointer callback */
  ds->pcm_buf_dma_ofs = pcm_buf_dma_ofs;

  if (xfercount &&
   /* Limit use of on card fifo for playback */
   ((on_card_bytes <= ds->period_bytes) ||
   (s->stream == SNDRV_PCM_STREAM_CAPTURE)))

  {

   unsigned int buf_ofs = ds->pcm_buf_host_rw_ofs % ds->buffer_bytes;
   unsigned int xfer1, xfer2;
   char *pd = &s->runtime->dma_area[buf_ofs];

   if (card->can_dma) { /* buffer wrap is handled at lower level */
    xfer1 = xfercount;
    xfer2 = 0;
   } else {
    xfer1 = min(xfercount, ds->buffer_bytes - buf_ofs);
    xfer2 = xfercount - xfer1;
   }

   if (s->stream == SNDRV_PCM_STREAM_PLAYBACK) {
    asihpi_dbg("write1, P=%d, xfer=%d, buf_ofs=%d\n",
     s->number, xfer1, buf_ofs);
    hpi_handle_error(
     hpi_outstream_write_buf(
      ds->h_stream, pd, xfer1,
      &ds->format));

    if (xfer2) {
     pd = s->runtime->dma_area;

     asihpi_dbg("write2, P=%d, xfer=%d, buf_ofs=%d\n",
       s->number,
       xfercount - xfer1, buf_ofs);
     hpi_handle_error(
      hpi_outstream_write_buf(
       ds->h_stream, pd,
       xfercount - xfer1,
       &ds->format));
    }
   } else {
    asihpi_dbg("read1, C=%d, xfer=%d\n",
     s->number, xfer1);
    hpi_handle_error(
     hpi_instream_read_buf(
      ds->h_stream,
      pd, xfer1));
    if (xfer2) {
     pd = s->runtime->dma_area;
     asihpi_dbg("read2, C=%d, xfer=%d\n",
      s->number, xfer2);
     hpi_handle_error(
      hpi_instream_read_buf(
       ds->h_stream,
       pd, xfer2));
    }
   }
   /* ? host_rw_ofs always ahead of elapsed_dma_ofs by preload size? */
   ds->pcm_buf_host_rw_ofs += xfercount;
   ds->pcm_buf_elapsed_dma_ofs += xfercount;
   snd_pcm_period_elapsed(s);
  }
 }

 if (!card->hpi->interrupt_mode && dpcm->respawn_timer)
  add_timer(&dpcm->timer);
}

static void snd_card_asihpi_isr(struct hpi_adapter *a)
{
 struct snd_card_asihpi *asihpi;

 WARN_ON(!a || !a->snd_card || !a->snd_card->private_data);
 asihpi = (struct snd_card_asihpi *)a->snd_card->private_data;
 if (asihpi->llmode_streampriv)
  snd_card_asihpi_timer_function(
   &asihpi->llmode_streampriv->timer);
}

/***************************** PLAYBACK OPS ****************/
static int snd_card_asihpi_playback_prepare(struct snd_pcm_substream *
         substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;

 hpi_handle_error(hpi_outstream_reset(dpcm->h_stream));
 dpcm->pcm_buf_host_rw_ofs = 0;
 dpcm->pcm_buf_dma_ofs = 0;
 dpcm->pcm_buf_elapsed_dma_ofs = 0;
 return 0;
}

static snd_pcm_uframes_t
snd_card_asihpi_playback_pointer(struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;
 snd_pcm_uframes_t ptr;
 char name[16];
 snd_pcm_debug_name(substream, name, sizeof(name));

 ptr = bytes_to_frames(runtime, dpcm->pcm_buf_dma_ofs  % dpcm->buffer_bytes);
 asihpi_dbg("%s, pointer=%ld\n", name, (unsigned long)ptr);
 return ptr;
}

static u64 snd_card_asihpi_playback_formats(struct snd_card_asihpi *asihpi,
      u32 h_stream)
{
 struct hpi_format hpi_format;
 u16 format;
 u16 err;
 u32 h_control;
 u32 sample_rate = 48000;
 u64 formats = 0;

 /* on cards without SRC, must query at valid rate,
* maybe set by external sync
*/
 err = hpi_mixer_get_control(asihpi->h_mixer,
      HPI_SOURCENODE_CLOCK_SOURCE, 0, 0, 0,
      HPI_CONTROL_SAMPLECLOCK, &h_control);

 if (!err)
  err = hpi_sample_clock_get_sample_rate(h_control,
    &sample_rate);

 for (format = HPI_FORMAT_PCM8_UNSIGNED;
      format <= HPI_FORMAT_PCM24_SIGNED; format++) {
  err = hpi_format_create(&hpi_format, asihpi->out_max_chans,
     format, sample_rate, 128000, 0);
  if (!err)
   err = hpi_outstream_query_format(h_stream, &hpi_format);
  if (!err && (hpi_to_alsa_formats[format] != INVALID_FORMAT))
   formats |= pcm_format_to_bits(hpi_to_alsa_formats[format]);
 }
 return formats;
}

static int snd_card_asihpi_playback_open(struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm;
 struct snd_card_asihpi *card = snd_pcm_substream_chip(substream);
 struct snd_pcm_hardware snd_card_asihpi_playback;
 int err;

 dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 if (dpcm == NULL)
  return -ENOMEM;

 err = hpi_outstream_open(card->hpi->adapter->index,
         substream->number, &dpcm->h_stream);
 hpi_handle_error(err);
 if (err)
  kfree(dpcm);
 if (err == HPI_ERROR_OBJ_ALREADY_OPEN)
  return -EBUSY;
 if (err)
  return -EIO;

 /*? also check ASI5000 samplerate source
    If external, only support external rate.
    If internal and other stream playing, can't switch
*/

 timer_setup(&dpcm->timer, snd_card_asihpi_timer_function, 0);
 dpcm->substream = substream;
 runtime->private_data = dpcm;
 runtime->private_free = snd_card_asihpi_runtime_free;

 memset(&snd_card_asihpi_playback, 0, sizeof(snd_card_asihpi_playback));
 if (!card->hpi->interrupt_mode) {
  snd_card_asihpi_playback.buffer_bytes_max = BUFFER_BYTES_MAX;
  snd_card_asihpi_playback.period_bytes_min = PERIOD_BYTES_MIN;
  snd_card_asihpi_playback.period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN;
  snd_card_asihpi_playback.periods_min = PERIODS_MIN;
  snd_card_asihpi_playback.periods_max = BUFFER_BYTES_MAX / PERIOD_BYTES_MIN;
 } else {
  size_t pbmin = card->update_interval_frames *
   card->out_max_chans;
  snd_card_asihpi_playback.buffer_bytes_max = BUFFER_BYTES_MAX;
  snd_card_asihpi_playback.period_bytes_min = pbmin;
  snd_card_asihpi_playback.period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN;
  snd_card_asihpi_playback.periods_min = PERIODS_MIN;
  snd_card_asihpi_playback.periods_max = BUFFER_BYTES_MAX / pbmin;
 }

 /* snd_card_asihpi_playback.fifo_size = 0; */
 snd_card_asihpi_playback.channels_max = card->out_max_chans;
 snd_card_asihpi_playback.channels_min = card->out_min_chans;
 snd_card_asihpi_playback.formats =
   snd_card_asihpi_playback_formats(card, dpcm->h_stream);

 snd_card_asihpi_pcm_samplerates(card,  &snd_card_asihpi_playback);

 snd_card_asihpi_playback.info = SNDRV_PCM_INFO_INTERLEAVED |
     SNDRV_PCM_INFO_DOUBLE |
     SNDRV_PCM_INFO_BATCH |
     SNDRV_PCM_INFO_BLOCK_TRANSFER |
     SNDRV_PCM_INFO_PAUSE |
     SNDRV_PCM_INFO_MMAP |
     SNDRV_PCM_INFO_MMAP_VALID;

 if (card->support_grouping) {
  snd_card_asihpi_playback.info |= SNDRV_PCM_INFO_SYNC_START;
  snd_pcm_set_sync(substream);
 }

 /* struct is copied, so can create initializer dynamically */
 runtime->hw = snd_card_asihpi_playback;

 if (card->can_dma)
  err = snd_pcm_hw_constraint_pow2(runtime, 0,
     SNDRV_PCM_HW_PARAM_BUFFER_BYTES);
 if (err < 0)
  return err;

 snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
  card->update_interval_frames);

 snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
  card->update_interval_frames, UINT_MAX);

 return 0;
}

static int snd_card_asihpi_playback_close(struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;

 hpi_handle_error(hpi_outstream_close(dpcm->h_stream));
 return 0;
}

static const struct snd_pcm_ops snd_card_asihpi_playback_mmap_ops = {
 .open = snd_card_asihpi_playback_open,
 .close = snd_card_asihpi_playback_close,
 .hw_params = snd_card_asihpi_pcm_hw_params,
 .hw_free = snd_card_asihpi_hw_free,
 .prepare = snd_card_asihpi_playback_prepare,
 .trigger = snd_card_asihpi_trigger,
 .pointer = snd_card_asihpi_playback_pointer,
};

/***************************** CAPTURE OPS ****************/
static snd_pcm_uframes_t
snd_card_asihpi_capture_pointer(struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;
 char name[16];
 snd_pcm_debug_name(substream, name, sizeof(name));

 asihpi_dbg("%s, pointer=%d\n", name, dpcm->pcm_buf_dma_ofs);
 /* NOTE Unlike playback can't use actual samples_played
for the capture position, because those samples aren't yet in
the local buffer available for reading.
*/
 return bytes_to_frames(runtime, dpcm->pcm_buf_dma_ofs % dpcm->buffer_bytes);
}

static int snd_card_asihpi_capture_prepare(struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi_pcm *dpcm = runtime->private_data;

 hpi_handle_error(hpi_instream_reset(dpcm->h_stream));
 dpcm->pcm_buf_host_rw_ofs = 0;
 dpcm->pcm_buf_dma_ofs = 0;
 dpcm->pcm_buf_elapsed_dma_ofs = 0;

 return 0;
}

static u64 snd_card_asihpi_capture_formats(struct snd_card_asihpi *asihpi,
     u32 h_stream)
{
 struct hpi_format hpi_format;
 u16 format;
 u16 err;
 u32 h_control;
 u32 sample_rate = 48000;
 u64 formats = 0;

 /* on cards without SRC, must query at valid rate,
maybe set by external sync */
 err = hpi_mixer_get_control(asihpi->h_mixer,
      HPI_SOURCENODE_CLOCK_SOURCE, 0, 0, 0,
      HPI_CONTROL_SAMPLECLOCK, &h_control);

 if (!err)
  err = hpi_sample_clock_get_sample_rate(h_control,
   &sample_rate);

 for (format = HPI_FORMAT_PCM8_UNSIGNED;
  format <= HPI_FORMAT_PCM24_SIGNED; format++) {

  err = hpi_format_create(&hpi_format, asihpi->in_max_chans,
     format, sample_rate, 128000, 0);
  if (!err)
   err = hpi_instream_query_format(h_stream, &hpi_format);
  if (!err && (hpi_to_alsa_formats[format] != INVALID_FORMAT))
   formats |= pcm_format_to_bits(hpi_to_alsa_formats[format]);
 }
 return formats;
}

static int snd_card_asihpi_capture_open(struct snd_pcm_substream *substream)
{
 struct snd_pcm_runtime *runtime = substream->runtime;
 struct snd_card_asihpi *card = snd_pcm_substream_chip(substream);
 struct snd_card_asihpi_pcm *dpcm;
 struct snd_pcm_hardware snd_card_asihpi_capture;
 int err;

 dpcm = kzalloc(sizeof(*dpcm), GFP_KERNEL);
 if (dpcm == NULL)
  return -ENOMEM;


 dev_dbg(card->card->dev, "capture open adapter %d stream %d\n",
  card->hpi->adapter->index, substream->number);

 err = hpi_handle_error(
     hpi_instream_open(card->hpi->adapter->index,
        substream->number, &dpcm->h_stream));
 if (err)
  kfree(dpcm);
 if (err == HPI_ERROR_OBJ_ALREADY_OPEN)
  return -EBUSY;
 if (err)
  return -EIO;

 timer_setup(&dpcm->timer, snd_card_asihpi_timer_function, 0);
 dpcm->substream = substream;
 runtime->private_data = dpcm;
 runtime->private_free = snd_card_asihpi_runtime_free;

 memset(&snd_card_asihpi_capture, 0, sizeof(snd_card_asihpi_capture));
 if (!card->hpi->interrupt_mode) {
  snd_card_asihpi_capture.buffer_bytes_max = BUFFER_BYTES_MAX;
  snd_card_asihpi_capture.period_bytes_min = PERIOD_BYTES_MIN;
  snd_card_asihpi_capture.period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN;
  snd_card_asihpi_capture.periods_min = PERIODS_MIN;
  snd_card_asihpi_capture.periods_max = BUFFER_BYTES_MAX / PERIOD_BYTES_MIN;
 } else {
  size_t pbmin = card->update_interval_frames *
   card->out_max_chans;
  snd_card_asihpi_capture.buffer_bytes_max = BUFFER_BYTES_MAX;
  snd_card_asihpi_capture.period_bytes_min = pbmin;
  snd_card_asihpi_capture.period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN;
  snd_card_asihpi_capture.periods_min = PERIODS_MIN;
  snd_card_asihpi_capture.periods_max = BUFFER_BYTES_MAX / pbmin;
 }
 /* snd_card_asihpi_capture.fifo_size = 0; */
 snd_card_asihpi_capture.channels_max = card->in_max_chans;
 snd_card_asihpi_capture.channels_min = card->in_min_chans;
 snd_card_asihpi_capture.formats =
  snd_card_asihpi_capture_formats(card, dpcm->h_stream);
 snd_card_asihpi_pcm_samplerates(card,  &snd_card_asihpi_capture);
 snd_card_asihpi_capture.info = SNDRV_PCM_INFO_INTERLEAVED |
     SNDRV_PCM_INFO_MMAP |
     SNDRV_PCM_INFO_MMAP_VALID;

 if (card->support_grouping)
  snd_card_asihpi_capture.info |= SNDRV_PCM_INFO_SYNC_START;

 runtime->hw = snd_card_asihpi_capture;

 if (card->can_dma)
  err = snd_pcm_hw_constraint_pow2(runtime, 0,
     SNDRV_PCM_HW_PARAM_BUFFER_BYTES);
 if (err < 0)
  return err;

 snd_pcm_hw_constraint_step(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
  card->update_interval_frames);
 snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
  card->update_interval_frames, UINT_MAX);

 snd_pcm_set_sync(substream);

 return 0;
}

static int snd_card_asihpi_capture_close(struct snd_pcm_substream *substream)
{
 struct snd_card_asihpi_pcm *dpcm = substream->runtime->private_data;

 hpi_handle_error(hpi_instream_close(dpcm->h_stream));
 return 0;
}

static const struct snd_pcm_ops snd_card_asihpi_capture_mmap_ops = {
 .open = snd_card_asihpi_capture_open,
 .close = snd_card_asihpi_capture_close,
 .hw_params = snd_card_asihpi_pcm_hw_params,
 .hw_free = snd_card_asihpi_hw_free,
 .prepare = snd_card_asihpi_capture_prepare,
 .trigger = snd_card_asihpi_trigger,
 .pointer = snd_card_asihpi_capture_pointer,
};

static int snd_card_asihpi_pcm_new(struct snd_card_asihpi *asihpi, int device)
{
 struct snd_pcm *pcm;
 int err;
 u16 num_instreams, num_outstreams, x16;
 u32 x32;

 err = hpi_adapter_get_info(asihpi->hpi->adapter->index,
   &num_outstreams, &num_instreams,
   &x16, &x32, &x16);

 err = snd_pcm_new(asihpi->card, "Asihpi PCM", device,
   num_outstreams, num_instreams, &pcm);
 if (err < 0)
  return err;

 /* pointer to ops struct is stored, dont change ops afterwards! */
 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
   &snd_card_asihpi_playback_mmap_ops);
 snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
   &snd_card_asihpi_capture_mmap_ops);

 pcm->private_data = asihpi;
 pcm->info_flags = 0;
 strscpy(pcm->name, "Asihpi PCM");

 /*? do we want to emulate MMAP for non-BBM cards?
Jack doesn't work with ALSAs MMAP emulation - WHY NOT? */
 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
           &asihpi->pci->dev,
           64*1024, BUFFER_BYTES_MAX);

 return 0;
}

/***************************** MIXER CONTROLS ****************/
struct hpi_control {
 u32 h_control;
 u16 control_type;
 u16 src_node_type;
 u16 src_node_index;
 u16 dst_node_type;
 u16 dst_node_index;
 u16 band;
 char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN]; /* copied to snd_ctl_elem_id.name[44]; */
};

static const char * const asihpi_tuner_band_names[] = {
 "invalid",
 "AM",
 "FM mono",
 "TV NTSC-M",
 "FM stereo",
 "AUX",
 "TV PAL BG",
 "TV PAL I",
 "TV PAL DK",
 "TV SECAM",
 "TV DAB",
};
/* Number of strings must match the enumerations for HPI_TUNER_BAND in hpi.h */
compile_time_assert(
 (ARRAY_SIZE(asihpi_tuner_band_names) ==
  (HPI_TUNER_BAND_LAST+1)),
 assert_tuner_band_names_size);

static const char * const asihpi_src_names[] = {
 "no source",
 "PCM",
 "Line",
 "Digital",
 "Tuner",
 "RF",
 "Clock",
 "Bitstream",
 "Mic",
 "Net",
 "Analog",
 "Adapter",
 "RTP",
 "Internal",
 "AVB",
 "BLU-Link"
};
/* Number of strings must match the enumerations for HPI_SOURCENODES in hpi.h */
compile_time_assert(
 (ARRAY_SIZE(asihpi_src_names) ==
  (HPI_SOURCENODE_LAST_INDEX-HPI_SOURCENODE_NONE+1)),
 assert_src_names_size);

static const char * const asihpi_dst_names[] = {
 "no destination",
 "PCM",
 "Line",
 "Digital",
 "RF",
 "Speaker",
 "Net",
 "Analog",
 "RTP",
 "AVB",
 "Internal",
 "BLU-Link"
};
/* Number of strings must match the enumerations for HPI_DESTNODES in hpi.h */
compile_time_assert(
 (ARRAY_SIZE(asihpi_dst_names) ==
  (HPI_DESTNODE_LAST_INDEX-HPI_DESTNODE_NONE+1)),
 assert_dst_names_size);

static inline int ctl_add(struct snd_card *card, struct snd_kcontrol_new *ctl,
    struct snd_card_asihpi *asihpi)
{
 int err;

 err = snd_ctl_add(card, snd_ctl_new1(ctl, asihpi));
 if (err < 0)
  return err;
 else if (mixer_dump)
  dev_info(&asihpi->pci->dev, "added %s(%d)\n", ctl->name, ctl->index);

 return 0;
}

/* Convert HPI control name and location into ALSA control name */
static void asihpi_ctl_init(struct snd_kcontrol_new *snd_control,
    struct hpi_control *hpi_ctl,
    char *name)
{
 char *dir;
 memset(snd_control, 0, sizeof(*snd_control));
 snd_control->name = hpi_ctl->name;
 snd_control->private_value = hpi_ctl->h_control;
 snd_control->iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 snd_control->index = 0;

 if (hpi_ctl->src_node_type + HPI_SOURCENODE_NONE == HPI_SOURCENODE_CLOCK_SOURCE)
  dir = ""; /* clock is neither capture nor playback */
 else if (hpi_ctl->dst_node_type + HPI_DESTNODE_NONE == HPI_DESTNODE_ISTREAM)
  dir = "Capture ";  /* On or towards a PCM capture destination*/
 else if ((hpi_ctl->src_node_type + HPI_SOURCENODE_NONE != HPI_SOURCENODE_OSTREAM) &&
  (!hpi_ctl->dst_node_type))
  dir = "Capture "; /* On a source node that is not PCM playback */
 else if (hpi_ctl->src_node_type &&
  (hpi_ctl->src_node_type + HPI_SOURCENODE_NONE != HPI_SOURCENODE_OSTREAM) &&
  (hpi_ctl->dst_node_type))
  dir = "Monitor Playback "; /* Between an input and an output */
 else
  dir = "Playback "; /* PCM Playback source, or  output node */

 if (hpi_ctl->src_node_type && hpi_ctl->dst_node_type)
  sprintf(hpi_ctl->name, "%s %d %s %d %s%s",
   asihpi_src_names[hpi_ctl->src_node_type],
   hpi_ctl->src_node_index,
   asihpi_dst_names[hpi_ctl->dst_node_type],
   hpi_ctl->dst_node_index,
   dir, name);
 else if (hpi_ctl->dst_node_type) {
  sprintf(hpi_ctl->name, "%s %d %s%s",
  asihpi_dst_names[hpi_ctl->dst_node_type],
  hpi_ctl->dst_node_index,
  dir, name);
 } else {
  sprintf(hpi_ctl->name, "%s %d %s%s",
  asihpi_src_names[hpi_ctl->src_node_type],
  hpi_ctl->src_node_index,
  dir, name);
 }
}

/*------------------------------------------------------------
   Volume controls
 ------------------------------------------------------------*/
#define VOL_STEP_mB 1
static int snd_asihpi_volume_info(struct snd_kcontrol *kcontrol,
      struct snd_ctl_elem_info *uinfo)
{
 u32 h_control = kcontrol->private_value;
 u32 count;
 u16 err;
 /* native gains are in millibels */
 short min_gain_mB;
 short max_gain_mB;
 short step_gain_mB;

 err = hpi_volume_query_range(h_control,
   &min_gain_mB, &max_gain_mB, &step_gain_mB);
 if (err) {
  max_gain_mB = 0;
  min_gain_mB = -10000;
  step_gain_mB = VOL_STEP_mB;
 }

 err = hpi_meter_query_channels(h_control, &count);
 if (err)
  count = HPI_MAX_CHANNELS;

 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 uinfo->count = count;
 uinfo->value.integer.min = min_gain_mB / VOL_STEP_mB;
 uinfo->value.integer.max = max_gain_mB / VOL_STEP_mB;
 uinfo->value.integer.step = step_gain_mB / VOL_STEP_mB;
 return 0;
}

static int snd_asihpi_volume_get(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 short an_gain_mB[HPI_MAX_CHANNELS];

 hpi_handle_error(hpi_volume_get_gain(h_control, an_gain_mB));
 ucontrol->value.integer.value[0] = an_gain_mB[0] / VOL_STEP_mB;
 ucontrol->value.integer.value[1] = an_gain_mB[1] / VOL_STEP_mB;

 return 0;
}

static int snd_asihpi_volume_put(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 short an_gain_mB[HPI_MAX_CHANNELS];

 an_gain_mB[0] =
     (ucontrol->value.integer.value[0]) * VOL_STEP_mB;
 an_gain_mB[1] =
     (ucontrol->value.integer.value[1]) * VOL_STEP_mB;
 /*  change = asihpi->mixer_volume[addr][0] != left ||
   asihpi->mixer_volume[addr][1] != right;
 */
 hpi_handle_error(hpi_volume_set_gain(h_control, an_gain_mB));
 return 1;
}

static const DECLARE_TLV_DB_SCALE(db_scale_100, -10000, VOL_STEP_mB, 0);

#define snd_asihpi_volume_mute_info snd_ctl_boolean_mono_info

static int snd_asihpi_volume_mute_get(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 u32 mute;

 hpi_handle_error(hpi_volume_get_mute(h_control, &mute));
 ucontrol->value.integer.value[0] = mute ? 0 : 1;

 return 0;
}

static int snd_asihpi_volume_mute_put(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 /* HPI currently only supports all or none muting of multichannel volume
ALSA Switch element has opposite sense to HPI mute: on==unmuted, off=muted
*/
 int mute =  ucontrol->value.integer.value[0] ? 0 : HPI_BITMASK_ALL_CHANNELS;
 hpi_handle_error(hpi_volume_set_mute(h_control, mute));
 return 1;
}

static int snd_asihpi_volume_add(struct snd_card_asihpi *asihpi,
     struct hpi_control *hpi_ctl)
{
 struct snd_card *card = asihpi->card;
 struct snd_kcontrol_new snd_control;
 int err;
 u32 mute;

 asihpi_ctl_init(&snd_control, hpi_ctl, "Volume");
 snd_control.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
    SNDRV_CTL_ELEM_ACCESS_TLV_READ;
 snd_control.info = snd_asihpi_volume_info;
 snd_control.get = snd_asihpi_volume_get;
 snd_control.put = snd_asihpi_volume_put;
 snd_control.tlv.p = db_scale_100;

 err = ctl_add(card, &snd_control, asihpi);
 if (err)
  return err;

 if (hpi_volume_get_mute(hpi_ctl->h_control, &mute) == 0) {
  asihpi_ctl_init(&snd_control, hpi_ctl, "Switch");
  snd_control.access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
  snd_control.info = snd_asihpi_volume_mute_info;
  snd_control.get = snd_asihpi_volume_mute_get;
  snd_control.put = snd_asihpi_volume_mute_put;
  err = ctl_add(card, &snd_control, asihpi);
 }
 return err;
}

/*------------------------------------------------------------
   Level controls
 ------------------------------------------------------------*/
static int snd_asihpi_level_info(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_info *uinfo)
{
 u32 h_control = kcontrol->private_value;
 u16 err;
 short min_gain_mB;
 short max_gain_mB;
 short step_gain_mB;

 err =
     hpi_level_query_range(h_control, &min_gain_mB,
          &max_gain_mB, &step_gain_mB);
 if (err) {
  max_gain_mB = 2400;
  min_gain_mB = -1000;
  step_gain_mB = 100;
 }

 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 uinfo->count = 2;
 uinfo->value.integer.min = min_gain_mB / HPI_UNITS_PER_dB;
 uinfo->value.integer.max = max_gain_mB / HPI_UNITS_PER_dB;
 uinfo->value.integer.step = step_gain_mB / HPI_UNITS_PER_dB;
 return 0;
}

static int snd_asihpi_level_get(struct snd_kcontrol *kcontrol,
    struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 short an_gain_mB[HPI_MAX_CHANNELS];

 hpi_handle_error(hpi_level_get_gain(h_control, an_gain_mB));
 ucontrol->value.integer.value[0] =
     an_gain_mB[0] / HPI_UNITS_PER_dB;
 ucontrol->value.integer.value[1] =
     an_gain_mB[1] / HPI_UNITS_PER_dB;

 return 0;
}

static int snd_asihpi_level_put(struct snd_kcontrol *kcontrol,
    struct snd_ctl_elem_value *ucontrol)
{
 int change;
 u32 h_control = kcontrol->private_value;
 short an_gain_mB[HPI_MAX_CHANNELS];

 an_gain_mB[0] =
     (ucontrol->value.integer.value[0]) * HPI_UNITS_PER_dB;
 an_gain_mB[1] =
     (ucontrol->value.integer.value[1]) * HPI_UNITS_PER_dB;
 /*  change = asihpi->mixer_level[addr][0] != left ||
   asihpi->mixer_level[addr][1] != right;
 */
 change = 1;
 hpi_handle_error(hpi_level_set_gain(h_control, an_gain_mB));
 return change;
}

static const DECLARE_TLV_DB_SCALE(db_scale_level, -1000, 100, 0);

static int snd_asihpi_level_add(struct snd_card_asihpi *asihpi,
    struct hpi_control *hpi_ctl)
{
 struct snd_card *card = asihpi->card;
 struct snd_kcontrol_new snd_control;

 /* can't use 'volume' cos some nodes have volume as well */
 asihpi_ctl_init(&snd_control, hpi_ctl, "Level");
 snd_control.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
    SNDRV_CTL_ELEM_ACCESS_TLV_READ;
 snd_control.info = snd_asihpi_level_info;
 snd_control.get = snd_asihpi_level_get;
 snd_control.put = snd_asihpi_level_put;
 snd_control.tlv.p = db_scale_level;

 return ctl_add(card, &snd_control, asihpi);
}

/*------------------------------------------------------------
   AESEBU controls
 ------------------------------------------------------------*/

/* AESEBU format */
static const char * const asihpi_aesebu_format_names[] = {
 "N/A", "S/PDIF", "AES/EBU" };

static int snd_asihpi_aesebu_format_info(struct snd_kcontrol *kcontrol,
      struct snd_ctl_elem_info *uinfo)
{
 return snd_ctl_enum_info(uinfo, 1, 3, asihpi_aesebu_format_names);
}

static int snd_asihpi_aesebu_format_get(struct snd_kcontrol *kcontrol,
   struct snd_ctl_elem_value *ucontrol,
   u16 (*func)(u32, u16 *))
{
 u32 h_control = kcontrol->private_value;
 u16 source, err;

 err = func(h_control, &source);

 /* default to N/A */
 ucontrol->value.enumerated.item[0] = 0;
 /* return success but set the control to N/A */
 if (err)
  return 0;
 if (source == HPI_AESEBU_FORMAT_SPDIF)
  ucontrol->value.enumerated.item[0] = 1;
 if (source == HPI_AESEBU_FORMAT_AESEBU)
  ucontrol->value.enumerated.item[0] = 2;

 return 0;
}

static int snd_asihpi_aesebu_format_put(struct snd_kcontrol *kcontrol,
   struct snd_ctl_elem_value *ucontrol,
    u16 (*func)(u32, u16))
{
 u32 h_control = kcontrol->private_value;

 /* default to S/PDIF */
 u16 source = HPI_AESEBU_FORMAT_SPDIF;

 if (ucontrol->value.enumerated.item[0] == 1)
  source = HPI_AESEBU_FORMAT_SPDIF;
 if (ucontrol->value.enumerated.item[0] == 2)
  source = HPI_AESEBU_FORMAT_AESEBU;

 if (func(h_control, source) != 0)
  return -EINVAL;

 return 1;
}

static int snd_asihpi_aesebu_rx_format_get(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol) {
 return snd_asihpi_aesebu_format_get(kcontrol, ucontrol,
     hpi_aesebu_receiver_get_format);
}

static int snd_asihpi_aesebu_rx_format_put(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol) {
 return snd_asihpi_aesebu_format_put(kcontrol, ucontrol,
     hpi_aesebu_receiver_set_format);
}

static int snd_asihpi_aesebu_rxstatus_info(struct snd_kcontrol *kcontrol,
      struct snd_ctl_elem_info *uinfo)
{
 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 uinfo->count = 1;

 uinfo->value.integer.min = 0;
 uinfo->value.integer.max = 0X1F;
 uinfo->value.integer.step = 1;

 return 0;
}

static int snd_asihpi_aesebu_rxstatus_get(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol) {

 u32 h_control = kcontrol->private_value;
 u16 status;

 hpi_handle_error(hpi_aesebu_receiver_get_error_status(
      h_control, &status));
 ucontrol->value.integer.value[0] = status;
 return 0;
}

static int snd_asihpi_aesebu_rx_add(struct snd_card_asihpi *asihpi,
        struct hpi_control *hpi_ctl)
{
 struct snd_card *card = asihpi->card;
 struct snd_kcontrol_new snd_control;

 asihpi_ctl_init(&snd_control, hpi_ctl, "Format");
 snd_control.access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
 snd_control.info = snd_asihpi_aesebu_format_info;
 snd_control.get = snd_asihpi_aesebu_rx_format_get;
 snd_control.put = snd_asihpi_aesebu_rx_format_put;


 if (ctl_add(card, &snd_control, asihpi) < 0)
  return -EINVAL;

 asihpi_ctl_init(&snd_control, hpi_ctl, "Status");
 snd_control.access =
     SNDRV_CTL_ELEM_ACCESS_VOLATILE | SNDRV_CTL_ELEM_ACCESS_READ;
 snd_control.info = snd_asihpi_aesebu_rxstatus_info;
 snd_control.get = snd_asihpi_aesebu_rxstatus_get;

 return ctl_add(card, &snd_control, asihpi);
}

static int snd_asihpi_aesebu_tx_format_get(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol) {
 return snd_asihpi_aesebu_format_get(kcontrol, ucontrol,
     hpi_aesebu_transmitter_get_format);
}

static int snd_asihpi_aesebu_tx_format_put(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol) {
 return snd_asihpi_aesebu_format_put(kcontrol, ucontrol,
     hpi_aesebu_transmitter_set_format);
}


static int snd_asihpi_aesebu_tx_add(struct snd_card_asihpi *asihpi,
        struct hpi_control *hpi_ctl)
{
 struct snd_card *card = asihpi->card;
 struct snd_kcontrol_new snd_control;

 asihpi_ctl_init(&snd_control, hpi_ctl, "Format");
 snd_control.access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
 snd_control.info = snd_asihpi_aesebu_format_info;
 snd_control.get = snd_asihpi_aesebu_tx_format_get;
 snd_control.put = snd_asihpi_aesebu_tx_format_put;

 return ctl_add(card, &snd_control, asihpi);
}

/*------------------------------------------------------------
   Tuner controls
 ------------------------------------------------------------*/

/* Gain */

static int snd_asihpi_tuner_gain_info(struct snd_kcontrol *kcontrol,
      struct snd_ctl_elem_info *uinfo)
{
 u32 h_control = kcontrol->private_value;
 u16 err;
 short idx;
 u16 gain_range[3];

 for (idx = 0; idx < 3; idx++) {
  err = hpi_tuner_query_gain(h_control,
       idx, &gain_range[idx]);
  if (err != 0)
   return err;
 }

 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 uinfo->count = 1;
 uinfo->value.integer.min = ((int)gain_range[0]) / HPI_UNITS_PER_dB;
 uinfo->value.integer.max = ((int)gain_range[1]) / HPI_UNITS_PER_dB;
 uinfo->value.integer.step = ((int) gain_range[2]) / HPI_UNITS_PER_dB;
 return 0;
}

static int snd_asihpi_tuner_gain_get(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 /*
struct snd_card_asihpi *asihpi = snd_kcontrol_chip(kcontrol);
*/
 u32 h_control = kcontrol->private_value;
 short gain;

 hpi_handle_error(hpi_tuner_get_gain(h_control, &gain));
 ucontrol->value.integer.value[0] = gain / HPI_UNITS_PER_dB;

 return 0;
}

static int snd_asihpi_tuner_gain_put(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 /*
struct snd_card_asihpi *asihpi = snd_kcontrol_chip(kcontrol);
*/
 u32 h_control = kcontrol->private_value;
 short gain;

 gain = (ucontrol->value.integer.value[0]) * HPI_UNITS_PER_dB;
 hpi_handle_error(hpi_tuner_set_gain(h_control, gain));

 return 1;
}

/* Band  */

static int asihpi_tuner_band_query(struct snd_kcontrol *kcontrol,
     u16 *band_list, u32 len) {
 u32 h_control = kcontrol->private_value;
 u16 err = 0;
 u32 i;

 for (i = 0; i < len; i++) {
  err = hpi_tuner_query_band(
    h_control, i, &band_list[i]);
  if (err != 0)
   break;
 }

 if (err && (err != HPI_ERROR_INVALID_OBJ_INDEX))
  return -EIO;

 return i;
}

static int snd_asihpi_tuner_band_info(struct snd_kcontrol *kcontrol,
      struct snd_ctl_elem_info *uinfo)
{
 u16 tuner_bands[HPI_TUNER_BAND_LAST];
 int num_bands = 0;

 num_bands = asihpi_tuner_band_query(kcontrol, tuner_bands,
    HPI_TUNER_BAND_LAST);

 if (num_bands < 0)
  return num_bands;

 return snd_ctl_enum_info(uinfo, 1, num_bands, asihpi_tuner_band_names);
}

static int snd_asihpi_tuner_band_get(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 /*
struct snd_card_asihpi *asihpi = snd_kcontrol_chip(kcontrol);
*/
 u16 band, idx;
 u16 tuner_bands[HPI_TUNER_BAND_LAST];
 __always_unused u32 num_bands;

 num_bands = asihpi_tuner_band_query(kcontrol, tuner_bands,
    HPI_TUNER_BAND_LAST);

 hpi_handle_error(hpi_tuner_get_band(h_control, &band));

 ucontrol->value.enumerated.item[0] = -1;
 for (idx = 0; idx < HPI_TUNER_BAND_LAST; idx++)
  if (tuner_bands[idx] == band) {
   ucontrol->value.enumerated.item[0] = idx;
   break;
  }

 return 0;
}

static int snd_asihpi_tuner_band_put(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 /*
struct snd_card_asihpi *asihpi = snd_kcontrol_chip(kcontrol);
*/
 u32 h_control = kcontrol->private_value;
 unsigned int idx;
 u16 band;
 u16 tuner_bands[HPI_TUNER_BAND_LAST];
 __always_unused u32 num_bands;

 num_bands = asihpi_tuner_band_query(kcontrol, tuner_bands,
   HPI_TUNER_BAND_LAST);

 idx = ucontrol->value.enumerated.item[0];
 if (idx >= ARRAY_SIZE(tuner_bands))
  idx = ARRAY_SIZE(tuner_bands) - 1;
 band = tuner_bands[idx];
 hpi_handle_error(hpi_tuner_set_band(h_control, band));

 return 1;
}

/* Freq */

static int snd_asihpi_tuner_freq_info(struct snd_kcontrol *kcontrol,
      struct snd_ctl_elem_info *uinfo)
{
 u32 h_control = kcontrol->private_value;
 u16 err;
 u16 tuner_bands[HPI_TUNER_BAND_LAST];
 u16 num_bands = 0, band_iter, idx;
 u32 freq_range[3], temp_freq_range[3];

 num_bands = asihpi_tuner_band_query(kcontrol, tuner_bands,
   HPI_TUNER_BAND_LAST);

 freq_range[0] = INT_MAX;
 freq_range[1] = 0;
 freq_range[2] = INT_MAX;

 for (band_iter = 0; band_iter < num_bands; band_iter++) {
  for (idx = 0; idx < 3; idx++) {
   err = hpi_tuner_query_frequency(h_control,
    idx, tuner_bands[band_iter],
    &temp_freq_range[idx]);
   if (err != 0)
    return err;
  }

  /* skip band with bogus stepping */
  if (temp_freq_range[2] <= 0)
   continue;

  if (temp_freq_range[0] < freq_range[0])
   freq_range[0] = temp_freq_range[0];
  if (temp_freq_range[1] > freq_range[1])
   freq_range[1] = temp_freq_range[1];
  if (temp_freq_range[2] < freq_range[2])
   freq_range[2] = temp_freq_range[2];
 }

 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 uinfo->count = 1;
 uinfo->value.integer.min = ((int)freq_range[0]);
 uinfo->value.integer.max = ((int)freq_range[1]);
 uinfo->value.integer.step = ((int)freq_range[2]);
 return 0;
}

static int snd_asihpi_tuner_freq_get(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 u32 freq;

 hpi_handle_error(hpi_tuner_get_frequency(h_control, &freq));
 ucontrol->value.integer.value[0] = freq;

 return 0;
}

static int snd_asihpi_tuner_freq_put(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 u32 freq;

 freq = ucontrol->value.integer.value[0];
 hpi_handle_error(hpi_tuner_set_frequency(h_control, freq));

 return 1;
}

/* Tuner control group initializer  */
static int snd_asihpi_tuner_add(struct snd_card_asihpi *asihpi,
    struct hpi_control *hpi_ctl)
{
 struct snd_card *card = asihpi->card;
 struct snd_kcontrol_new snd_control;

 snd_control.private_value = hpi_ctl->h_control;
 snd_control.access = SNDRV_CTL_ELEM_ACCESS_READWRITE;

 if (!hpi_tuner_get_gain(hpi_ctl->h_control, NULL)) {
  asihpi_ctl_init(&snd_control, hpi_ctl, "Gain");
  snd_control.info = snd_asihpi_tuner_gain_info;
  snd_control.get = snd_asihpi_tuner_gain_get;
  snd_control.put = snd_asihpi_tuner_gain_put;

  if (ctl_add(card, &snd_control, asihpi) < 0)
   return -EINVAL;
 }

 asihpi_ctl_init(&snd_control, hpi_ctl, "Band");
 snd_control.info = snd_asihpi_tuner_band_info;
 snd_control.get = snd_asihpi_tuner_band_get;
 snd_control.put = snd_asihpi_tuner_band_put;

 if (ctl_add(card, &snd_control, asihpi) < 0)
  return -EINVAL;

 asihpi_ctl_init(&snd_control, hpi_ctl, "Freq");
 snd_control.info = snd_asihpi_tuner_freq_info;
 snd_control.get = snd_asihpi_tuner_freq_get;
 snd_control.put = snd_asihpi_tuner_freq_put;

 return ctl_add(card, &snd_control, asihpi);
}

/*------------------------------------------------------------
   Meter controls
 ------------------------------------------------------------*/
static int snd_asihpi_meter_info(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_info *uinfo)
{
 u32 h_control = kcontrol->private_value;
 u32 count;
 u16 err;
 err = hpi_meter_query_channels(h_control, &count);
 if (err)
  count = HPI_MAX_CHANNELS;

 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
 uinfo->count = count;
 uinfo->value.integer.min = 0;
 uinfo->value.integer.max = 0x7FFFFFFF;
 return 0;
}

/* linear values for 10dB steps */
static const int log2lin[] = {
 0x7FFFFFFF, /* 0dB */
 679093956,
 214748365,
  67909396,
  21474837,
   6790940,
   2147484, /* -60dB */
    679094,
    214748, /* -80 */
     67909,
     21475, /* -100 */
      6791,
      2147,
       679,
       214,
        68,
        21,
  7,
  2
};

static int snd_asihpi_meter_get(struct snd_kcontrol *kcontrol,
    struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 short an_gain_mB[HPI_MAX_CHANNELS], i;
 u16 err;

 err = hpi_meter_get_peak(h_control, an_gain_mB);

 for (i = 0; i < HPI_MAX_CHANNELS; i++) {
  if (err) {
   ucontrol->value.integer.value[i] = 0;
  } else if (an_gain_mB[i] >= 0) {
   ucontrol->value.integer.value[i] =
    an_gain_mB[i] << 16;
  } else {
   /* -ve is log value in millibels < -60dB,
* convert to (roughly!) linear,
*/
   ucontrol->value.integer.value[i] =
     log2lin[an_gain_mB[i] / -1000];
  }
 }
 return 0;
}

static int snd_asihpi_meter_add(struct snd_card_asihpi *asihpi,
    struct hpi_control *hpi_ctl, int subidx)
{
 struct snd_card *card = asihpi->card;
 struct snd_kcontrol_new snd_control;

 asihpi_ctl_init(&snd_control, hpi_ctl, "Meter");
 snd_control.access =
     SNDRV_CTL_ELEM_ACCESS_VOLATILE | SNDRV_CTL_ELEM_ACCESS_READ;
 snd_control.info = snd_asihpi_meter_info;
 snd_control.get = snd_asihpi_meter_get;

 snd_control.index = subidx;

 return ctl_add(card, &snd_control, asihpi);
}

/*------------------------------------------------------------
   Multiplexer controls
 ------------------------------------------------------------*/
static int snd_card_asihpi_mux_count_sources(struct snd_kcontrol *snd_control)
{
 u32 h_control = snd_control->private_value;
 struct hpi_control hpi_ctl;
 int s, err;
 for (s = 0; s < 32; s++) {
  err = hpi_multiplexer_query_source(h_control, s,
        &hpi_ctl.
        src_node_type,
        &hpi_ctl.
        src_node_index);
  if (err)
   break;
 }
 return s;
}

static int snd_asihpi_mux_info(struct snd_kcontrol *kcontrol,
          struct snd_ctl_elem_info *uinfo)
{
 u16 src_node_type, src_node_index;
 u32 h_control = kcontrol->private_value;

 uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
 uinfo->count = 1;
 uinfo->value.enumerated.items =
     snd_card_asihpi_mux_count_sources(kcontrol);

 if (uinfo->value.enumerated.item >= uinfo->value.enumerated.items)
  uinfo->value.enumerated.item =
      uinfo->value.enumerated.items - 1;

 hpi_multiplexer_query_source(h_control,
         uinfo->value.enumerated.item,
         &src_node_type, &src_node_index);

 sprintf(uinfo->value.enumerated.name, "%s %d",
  asihpi_src_names[src_node_type - HPI_SOURCENODE_NONE],
  src_node_index);
 return 0;
}

static int snd_asihpi_mux_get(struct snd_kcontrol *kcontrol,
         struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 u16 source_type, source_index;
 u16 src_node_type, src_node_index;
 int s;

 hpi_handle_error(hpi_multiplexer_get_source(h_control,
    &source_type, &source_index));
 /* Should cache this search result! */
 for (s = 0; s < 256; s++) {
  if (hpi_multiplexer_query_source(h_control, s,
         &src_node_type, &src_node_index))
   break;

  if ((source_type == src_node_type)
      && (source_index == src_node_index)) {
   ucontrol->value.enumerated.item[0] = s;
   return 0;
  }
 }
 pr_warn("%s: Control %x failed to match mux source %hu %hu\n",
  __func__, h_control, source_type, source_index);
 ucontrol->value.enumerated.item[0] = 0;
 return 0;
}

static int snd_asihpi_mux_put(struct snd_kcontrol *kcontrol,
         struct snd_ctl_elem_value *ucontrol)
{
 int change;
 u32 h_control = kcontrol->private_value;
 u16 source_type, source_index;
 u16 e;

 change = 1;

 e = hpi_multiplexer_query_source(h_control,
        ucontrol->value.enumerated.item[0],
        &source_type, &source_index);
 if (!e)
  hpi_handle_error(
   hpi_multiplexer_set_source(h_control,
      source_type, source_index));
 return change;
}


static int  snd_asihpi_mux_add(struct snd_card_asihpi *asihpi,
          struct hpi_control *hpi_ctl)
{
 struct snd_card *card = asihpi->card;
 struct snd_kcontrol_new snd_control;

 asihpi_ctl_init(&snd_control, hpi_ctl, "Route");
 snd_control.access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
 snd_control.info = snd_asihpi_mux_info;
 snd_control.get = snd_asihpi_mux_get;
 snd_control.put = snd_asihpi_mux_put;

 return ctl_add(card, &snd_control, asihpi);

}

/*------------------------------------------------------------
   Channel mode controls
 ------------------------------------------------------------*/
static int snd_asihpi_cmode_info(struct snd_kcontrol *kcontrol,
     struct snd_ctl_elem_info *uinfo)
{
 static const char * const mode_names[HPI_CHANNEL_MODE_LAST + 1] = {
  "invalid",
  "Normal", "Swap",
  "From Left", "From Right",
  "To Left", "To Right"
 };

 u32 h_control = kcontrol->private_value;
 u16 mode;
 int i;
 const char *mapped_names[6];
 int valid_modes = 0;

 /* HPI channel mode values can be from 1 to 6
Some adapters only support a contiguous subset
*/
 for (i = 0; i < HPI_CHANNEL_MODE_LAST; i++)
  if (!hpi_channel_mode_query_mode(
   h_control, i, &mode)) {
   mapped_names[valid_modes] = mode_names[mode];
   valid_modes++;
   }

 if (!valid_modes)
  return -EINVAL;

 return snd_ctl_enum_info(uinfo, 1, valid_modes, mapped_names);
}

static int snd_asihpi_cmode_get(struct snd_kcontrol *kcontrol,
    struct snd_ctl_elem_value *ucontrol)
{
 u32 h_control = kcontrol->private_value;
 u16 mode;

 if (hpi_channel_mode_get(h_control, &mode))
  mode = 1;

 ucontrol->value.enumerated.item[0] = mode - 1;

 return 0;
}

static int snd_asihpi_cmode_put(struct snd_kcontrol *kcontrol,
    struct snd_ctl_elem_value *ucontrol)
{
 int change;
 u32 h_control = kcontrol->private_value;

 change = 1;

 hpi_handle_error(hpi_channel_mode_set(h_control,
      ucontrol->value.enumerated.item[0] + 1));
 return change;
}


static int snd_asihpi_cmode_add(struct snd_card_asihpi *asihpi,
    struct hpi_control *hpi_ctl)
{
 struct snd_card *card = asihpi->card;
 struct snd_kcontrol_new snd_control;

 asihpi_ctl_init(&snd_control, hpi_ctl, "Mode");
 snd_control.access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
 snd_control.info = snd_asihpi_cmode_info;
 snd_control.get = snd_asihpi_cmode_get;
 snd_control.put = snd_asihpi_cmode_put;

 return ctl_add(card, &snd_control, asihpi);
}

/*------------------------------------------------------------
   Sampleclock source  controls
 ------------------------------------------------------------*/
static const char * const sampleclock_sources[] = {
 "N/A", "Local PLL", "Digital Sync", "Word External", "Word Header",
 "SMPTE", "Digital1", "Auto", "Network", "Invalid",
 "Prev Module", "BLU-Link",
 "Digital2", "Digital3", "Digital4", "Digital5",
 "Digital6", "Digital7", "Digital8"};

 /* Number of strings must match expected enumerated values */
 compile_time_assert(
  (ARRAY_SIZE(sampleclock_sources) == MAX_CLOCKSOURCES),
  assert_sampleclock_sources_size);

static int snd_asihpi_clksrc_info(struct snd_kcontrol *kcontrol,
      struct snd_ctl_elem_info *uinfo)
{
 struct snd_card_asihpi *asihpi = snd_kcontrol_chip(kcontrol);
 struct clk_cache *clkcache = &asihpi->cc;
 uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
 uinfo->count = 1;
 uinfo->value.enumerated.items = clkcache->count;

 if (uinfo->value.enumerated.item >= uinfo->value.enumerated.items)
  uinfo->value.enumerated.item =
    uinfo->value.enumerated.items - 1;

 strscpy(uinfo->value.enumerated.name,
--> --------------------

--> maximum size reached

--> --------------------