summaryrefslogtreecommitdiffstats
path: root/src/hw/audio/lm4549.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/hw/audio/lm4549.c')
-rw-r--r--src/hw/audio/lm4549.c335
1 files changed, 335 insertions, 0 deletions
diff --git a/src/hw/audio/lm4549.c b/src/hw/audio/lm4549.c
new file mode 100644
index 0000000..380ef60
--- /dev/null
+++ b/src/hw/audio/lm4549.c
@@ -0,0 +1,335 @@
+/*
+ * LM4549 Audio Codec Interface
+ *
+ * Copyright (c) 2011
+ * Written by Mathieu Sonet - www.elasticsheep.com
+ *
+ * This code is licensed under the GPL.
+ *
+ * *****************************************************************
+ *
+ * This driver emulates the LM4549 codec.
+ *
+ * It supports only one playback voice and no record voice.
+ */
+
+#include "hw/hw.h"
+#include "audio/audio.h"
+#include "lm4549.h"
+
+#if 0
+#define LM4549_DEBUG 1
+#endif
+
+#if 0
+#define LM4549_DUMP_DAC_INPUT 1
+#endif
+
+#ifdef LM4549_DEBUG
+#define DPRINTF(fmt, ...) \
+do { printf("lm4549: " fmt , ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) do {} while (0)
+#endif
+
+#if defined(LM4549_DUMP_DAC_INPUT)
+#include <stdio.h>
+static FILE *fp_dac_input;
+#endif
+
+/* LM4549 register list */
+enum {
+ LM4549_Reset = 0x00,
+ LM4549_Master_Volume = 0x02,
+ LM4549_Line_Out_Volume = 0x04,
+ LM4549_Master_Volume_Mono = 0x06,
+ LM4549_PC_Beep_Volume = 0x0A,
+ LM4549_Phone_Volume = 0x0C,
+ LM4549_Mic_Volume = 0x0E,
+ LM4549_Line_In_Volume = 0x10,
+ LM4549_CD_Volume = 0x12,
+ LM4549_Video_Volume = 0x14,
+ LM4549_Aux_Volume = 0x16,
+ LM4549_PCM_Out_Volume = 0x18,
+ LM4549_Record_Select = 0x1A,
+ LM4549_Record_Gain = 0x1C,
+ LM4549_General_Purpose = 0x20,
+ LM4549_3D_Control = 0x22,
+ LM4549_Powerdown_Ctrl_Stat = 0x26,
+ LM4549_Ext_Audio_ID = 0x28,
+ LM4549_Ext_Audio_Stat_Ctrl = 0x2A,
+ LM4549_PCM_Front_DAC_Rate = 0x2C,
+ LM4549_PCM_ADC_Rate = 0x32,
+ LM4549_Vendor_ID1 = 0x7C,
+ LM4549_Vendor_ID2 = 0x7E
+};
+
+static void lm4549_reset(lm4549_state *s)
+{
+ uint16_t *regfile = s->regfile;
+
+ regfile[LM4549_Reset] = 0x0d50;
+ regfile[LM4549_Master_Volume] = 0x8008;
+ regfile[LM4549_Line_Out_Volume] = 0x8000;
+ regfile[LM4549_Master_Volume_Mono] = 0x8000;
+ regfile[LM4549_PC_Beep_Volume] = 0x0000;
+ regfile[LM4549_Phone_Volume] = 0x8008;
+ regfile[LM4549_Mic_Volume] = 0x8008;
+ regfile[LM4549_Line_In_Volume] = 0x8808;
+ regfile[LM4549_CD_Volume] = 0x8808;
+ regfile[LM4549_Video_Volume] = 0x8808;
+ regfile[LM4549_Aux_Volume] = 0x8808;
+ regfile[LM4549_PCM_Out_Volume] = 0x8808;
+ regfile[LM4549_Record_Select] = 0x0000;
+ regfile[LM4549_Record_Gain] = 0x8000;
+ regfile[LM4549_General_Purpose] = 0x0000;
+ regfile[LM4549_3D_Control] = 0x0101;
+ regfile[LM4549_Powerdown_Ctrl_Stat] = 0x000f;
+ regfile[LM4549_Ext_Audio_ID] = 0x0001;
+ regfile[LM4549_Ext_Audio_Stat_Ctrl] = 0x0000;
+ regfile[LM4549_PCM_Front_DAC_Rate] = 0xbb80;
+ regfile[LM4549_PCM_ADC_Rate] = 0xbb80;
+ regfile[LM4549_Vendor_ID1] = 0x4e53;
+ regfile[LM4549_Vendor_ID2] = 0x4331;
+}
+
+static void lm4549_audio_transfer(lm4549_state *s)
+{
+ uint32_t written_bytes, written_samples;
+ uint32_t i;
+
+ /* Activate the voice */
+ AUD_set_active_out(s->voice, 1);
+ s->voice_is_active = 1;
+
+ /* Try to write the buffer content */
+ written_bytes = AUD_write(s->voice, s->buffer,
+ s->buffer_level * sizeof(uint16_t));
+ written_samples = written_bytes >> 1;
+
+#if defined(LM4549_DUMP_DAC_INPUT)
+ fwrite(s->buffer, sizeof(uint8_t), written_bytes, fp_dac_input);
+#endif
+
+ s->buffer_level -= written_samples;
+
+ if (s->buffer_level > 0) {
+ /* Move the data back to the start of the buffer */
+ for (i = 0; i < s->buffer_level; i++) {
+ s->buffer[i] = s->buffer[i + written_samples];
+ }
+ }
+}
+
+static void lm4549_audio_out_callback(void *opaque, int free)
+{
+ lm4549_state *s = (lm4549_state *)opaque;
+ static uint32_t prev_buffer_level;
+
+#ifdef LM4549_DEBUG
+ int size = AUD_get_buffer_size_out(s->voice);
+ DPRINTF("audio_out_callback size = %i free = %i\n", size, free);
+#endif
+
+ /* Detect that no data are consumed
+ => disable the voice */
+ if (s->buffer_level == prev_buffer_level) {
+ AUD_set_active_out(s->voice, 0);
+ s->voice_is_active = 0;
+ }
+ prev_buffer_level = s->buffer_level;
+
+ /* Check if a buffer transfer is pending */
+ if (s->buffer_level == LM4549_BUFFER_SIZE) {
+ lm4549_audio_transfer(s);
+
+ /* Request more data */
+ if (s->data_req_cb != NULL) {
+ (s->data_req_cb)(s->opaque);
+ }
+ }
+}
+
+uint32_t lm4549_read(lm4549_state *s, hwaddr offset)
+{
+ uint16_t *regfile = s->regfile;
+ uint32_t value = 0;
+
+ /* Read the stored value */
+ assert(offset < 128);
+ value = regfile[offset];
+
+ DPRINTF("read [0x%02x] = 0x%04x\n", offset, value);
+
+ return value;
+}
+
+void lm4549_write(lm4549_state *s,
+ hwaddr offset, uint32_t value)
+{
+ uint16_t *regfile = s->regfile;
+
+ assert(offset < 128);
+ DPRINTF("write [0x%02x] = 0x%04x\n", offset, value);
+
+ switch (offset) {
+ case LM4549_Reset:
+ lm4549_reset(s);
+ break;
+
+ case LM4549_PCM_Front_DAC_Rate:
+ regfile[LM4549_PCM_Front_DAC_Rate] = value;
+ DPRINTF("DAC rate change = %i\n", value);
+
+ /* Re-open a voice with the new sample rate */
+ struct audsettings as;
+ as.freq = value;
+ as.nchannels = 2;
+ as.fmt = AUD_FMT_S16;
+ as.endianness = 0;
+
+ s->voice = AUD_open_out(
+ &s->card,
+ s->voice,
+ "lm4549.out",
+ s,
+ lm4549_audio_out_callback,
+ &as
+ );
+ break;
+
+ case LM4549_Powerdown_Ctrl_Stat:
+ value &= ~0xf;
+ value |= regfile[LM4549_Powerdown_Ctrl_Stat] & 0xf;
+ regfile[LM4549_Powerdown_Ctrl_Stat] = value;
+ break;
+
+ case LM4549_Ext_Audio_ID:
+ case LM4549_Vendor_ID1:
+ case LM4549_Vendor_ID2:
+ DPRINTF("Write to read-only register 0x%x\n", (int)offset);
+ break;
+
+ default:
+ /* Store the new value */
+ regfile[offset] = value;
+ break;
+ }
+}
+
+uint32_t lm4549_write_samples(lm4549_state *s, uint32_t left, uint32_t right)
+{
+ /* The left and right samples are in 20-bit resolution.
+ The LM4549 has 18-bit resolution and only uses the bits [19:2].
+ This model supports 16-bit playback.
+ */
+
+ if (s->buffer_level > LM4549_BUFFER_SIZE - 2) {
+ DPRINTF("write_sample Buffer full\n");
+ return 0;
+ }
+
+ /* Store 16-bit samples in the buffer */
+ s->buffer[s->buffer_level++] = (left >> 4);
+ s->buffer[s->buffer_level++] = (right >> 4);
+
+ if (s->buffer_level == LM4549_BUFFER_SIZE) {
+ /* Trigger the transfer of the buffer to the audio host */
+ lm4549_audio_transfer(s);
+ }
+
+ return 1;
+}
+
+static int lm4549_post_load(void *opaque, int version_id)
+{
+ lm4549_state *s = (lm4549_state *)opaque;
+ uint16_t *regfile = s->regfile;
+
+ /* Re-open a voice with the current sample rate */
+ uint32_t freq = regfile[LM4549_PCM_Front_DAC_Rate];
+
+ DPRINTF("post_load freq = %i\n", freq);
+ DPRINTF("post_load voice_is_active = %i\n", s->voice_is_active);
+
+ struct audsettings as;
+ as.freq = freq;
+ as.nchannels = 2;
+ as.fmt = AUD_FMT_S16;
+ as.endianness = 0;
+
+ s->voice = AUD_open_out(
+ &s->card,
+ s->voice,
+ "lm4549.out",
+ s,
+ lm4549_audio_out_callback,
+ &as
+ );
+
+ /* Request data */
+ if (s->voice_is_active == 1) {
+ lm4549_audio_out_callback(s, AUD_get_buffer_size_out(s->voice));
+ }
+
+ return 0;
+}
+
+void lm4549_init(lm4549_state *s, lm4549_callback data_req_cb, void* opaque)
+{
+ struct audsettings as;
+
+ /* Store the callback and opaque pointer */
+ s->data_req_cb = data_req_cb;
+ s->opaque = opaque;
+
+ /* Init the registers */
+ lm4549_reset(s);
+
+ /* Register an audio card */
+ AUD_register_card("lm4549", &s->card);
+
+ /* Open a default voice */
+ as.freq = 48000;
+ as.nchannels = 2;
+ as.fmt = AUD_FMT_S16;
+ as.endianness = 0;
+
+ s->voice = AUD_open_out(
+ &s->card,
+ s->voice,
+ "lm4549.out",
+ s,
+ lm4549_audio_out_callback,
+ &as
+ );
+
+ AUD_set_volume_out(s->voice, 0, 255, 255);
+
+ s->voice_is_active = 0;
+
+ /* Reset the input buffer */
+ memset(s->buffer, 0x00, sizeof(s->buffer));
+ s->buffer_level = 0;
+
+#if defined(LM4549_DUMP_DAC_INPUT)
+ fp_dac_input = fopen("lm4549_dac_input.pcm", "wb");
+ if (!fp_dac_input) {
+ hw_error("Unable to open lm4549_dac_input.pcm for writing\n");
+ }
+#endif
+}
+
+const VMStateDescription vmstate_lm4549_state = {
+ .name = "lm4549_state",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .post_load = lm4549_post_load,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(voice_is_active, lm4549_state),
+ VMSTATE_UINT16_ARRAY(regfile, lm4549_state, 128),
+ VMSTATE_UINT16_ARRAY(buffer, lm4549_state, LM4549_BUFFER_SIZE),
+ VMSTATE_UINT32(buffer_level, lm4549_state),
+ VMSTATE_END_OF_LIST()
+ }
+};
OpenPOWER on IntegriCloud