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CS423x: Add untested Mu-Law, A-Law and ADPCM playback

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This commit is contained in:
RichardG867
2022-03-07 16:00:39 -03:00
parent 67f6525f85
commit 07f060bc18
1 changed files with 100 additions and 5 deletions
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105
src/sound/snd_ad1848.c
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@@ -37,6 +37,10 @@
static int ad1848_vols_7bits[128];
static double ad1848_vols_5bits_aux_gain[32];
/* Borrowed from snd_sb_dsp */
extern int8_t scaleMap4[64];
extern uint8_t adjustMap4[64];
void
ad1848_setirq(ad1848_t *ad1848, int irq)
{
@@ -253,7 +257,8 @@ ad1848_write(uint16_t addr, uint8_t val, void *priv)
return;
case 14:
ad1848->count = ad1848->regs[15] | (val << 8);
ad1848->count = ad1848->regs[15] | (val << 8);
ad1848->adpcm_pos = 0;
break;
case 17:
@@ -414,6 +419,64 @@ ad1848_update(ad1848_t *ad1848)
}
}
static int16_t
ad1848_process_mulaw(uint8_t byte)
{
int pos;
int16_t dec;
dec = (~byte) & 0x7f;
pos = ((dec & 0xf0) >> 4) + 5;
dec = (1 << pos) | ((dec & 0x0f) << (pos - 4)) | (1 << (pos - 5));
dec = (dec - 33) << 2;
return (byte & 0x80) ? dec : -dec;
}
static int16_t
ad1848_process_alaw(uint8_t byte)
{
int pos;
int16_t dec;
byte ^= 0x55;
uint8_t sample = byte & 0x7f;
pos = ((sample & 0xf0) >> 4) + 4;
if (pos == 4)
dec = (sample << 4) | 0x08;
else
dec = (1 << (pos + 3)) | ((sample & 0x0f) << (pos - 1)) | (1 << (pos - 2));
return (byte & 0x80) ? -dec : dec;
}
static int16_t
ad1848_process_adpcm(ad1848_t *ad1848)
{
int temp;
if (ad1848->adpcm_pos) {
temp = (ad1848->adpcm_data & 0x0f) + ad1848->adpcm_step;
} else {
ad1848->adpcm_data = dma_channel_read(ad1848->dma);
temp = (ad1848->adpcm_data >> 4) + ad1848->adpcm_step;
}
ad1848->adpcm_pos ^= 1;
if (temp < 0)
temp = 0;
else if (temp > 63)
temp = 63;
ad1848->adpcm_ref += scaleMap4[temp];
if (ad1848->adpcm_ref > 0xff)
ad1848->adpcm_ref = 0xff;
else if (ad1848->adpcm_ref < 0x00)
ad1848->adpcm_ref = 0x00;
ad1848->adpcm_step = (ad1848->adpcm_step + adjustMap4[temp]) & 0xff;
return (ad1848->adpcm_ref ^ 0x80) << 8;
}
static void
ad1848_poll(void *priv)
{
@@ -431,12 +494,21 @@ ad1848_poll(void *priv)
switch (ad1848->regs[8] & ad1848->fmt_mask) {
case 0x00: /* Mono, 8-bit PCM */
ad1848->out_l = ad1848->out_r = (dma_channel_read(ad1848->dma) ^ 0x80) * 256;
ad1848->out_l = ad1848->out_r = (dma_channel_read(ad1848->dma) ^ 0x80) << 8;
break;
case 0x10: /* Stereo, 8-bit PCM */
ad1848->out_l = (dma_channel_read(ad1848->dma) ^ 0x80) * 256;
ad1848->out_r = (dma_channel_read(ad1848->dma) ^ 0x80) * 256;
ad1848->out_l = (dma_channel_read(ad1848->dma) ^ 0x80) << 8;
ad1848->out_r = (dma_channel_read(ad1848->dma) ^ 0x80) << 8;
break;
case 0x20: /* Mono, 8-bit Mu-Law */
ad1848->out_l = ad1848->out_r = ad1848_process_mulaw(dma_channel_read(ad1848->dma));
break;
case 0x30: /* Stereo, 8-bit Mu-Law */
ad1848->out_l = ad1848_process_mulaw(dma_channel_read(ad1848->dma));
ad1848->out_r = ad1848_process_mulaw(dma_channel_read(ad1848->dma));
break;
case 0x40: /* Mono, 16-bit PCM little endian */
@@ -451,6 +523,26 @@ ad1848_poll(void *priv)
ad1848->out_r = (dma_channel_read(ad1848->dma) << 8) | temp;
break;
case 0x60: /* Mono, 8-bit A-Law */
ad1848->out_l = ad1848->out_r = ad1848_process_alaw(dma_channel_read(ad1848->dma));
break;
case 0x70: /* Stereo, 8-bit A-Law */
ad1848->out_l = ad1848_process_alaw(dma_channel_read(ad1848->dma));
ad1848->out_r = ad1848_process_alaw(dma_channel_read(ad1848->dma));
break;
/* 0x80 and 0x90 reserved */
case 0xa0: /* Mono, 4-bit ADPCM */
ad1848->out_l = ad1848->out_r = ad1848_process_adpcm(ad1848);
break;
case 0xb0: /* Stereo, 4-bit ADPCM */
ad1848->out_l = ad1848_process_adpcm(ad1848);
ad1848->out_r = ad1848_process_adpcm(ad1848);
break;
case 0xc0: /* Mono, 16-bit PCM big endian */
temp = dma_channel_read(ad1848->dma);
ad1848->out_l = ad1848->out_r = dma_channel_read(ad1848->dma) | (temp << 8);
@@ -462,6 +554,8 @@ ad1848_poll(void *priv)
temp = dma_channel_read(ad1848->dma);
ad1848->out_r = dma_channel_read(ad1848->dma) | (temp << 8);
break;
/* 0xe0 and 0xf0 reserved */
}
if (ad1848->regs[6] & 0x80)
@@ -475,7 +569,8 @@ ad1848_poll(void *priv)
ad1848->out_r = (ad1848->out_r * ad1848_vols_7bits[ad1848->regs[7] & ad1848->wave_vol_mask]) >> 16;
if (ad1848->count < 0) {
ad1848->count = ad1848->regs[15] | (ad1848->regs[14] << 8);
ad1848->count = ad1848->regs[15] | (ad1848->regs[14] << 8);
ad1848->adpcm_pos = 0;
if (!(ad1848->status & 0x01)) {
ad1848->status |= 0x01;
ad1848->regs[24] |= 0x10;