Emulated audio

Audio devices of the emulators. More...

Data Structures
struct	pbl_audio_qemu
	QEMU audio device. More...
struct	pbl_audio_host_mic
	Host microphone. More...

Macros
#define	PBL_AUDIO_QEMU_DEFINE(sym, _name, _base, _irq)
	Define the QEMU audio device, a playback device.
#define	PBL_AUDIO_HOST_MIC_DEFINE(sym, _name)
	Define the host microphone, a capture device.

Functions
void	pbl_audio_qemu_irq_handler (const struct pbl_audio_qemu *dev)
	QEMU audio device interrupt handler, to connect with PBL_IRQ_CONNECT().
void	qemu_mic_msg_callback (const uint8_t *data, uint32_t len)
	Handle a QemuProtocol_MicAudio message from the host.

Detailed Description

Audio devices of the emulators.

The QEMU audio device plays mono through the host. The host microphone records mono audio the host sends over the QEMU channel, and silence when it sends none, paced by a timer; it also runs on native builds.

PBL_AUDIO_QEMU_DEFINE(s_speaker, "speaker", QEMU_AUDIO_BASE, PBL_IRQN(AUDIO));
PBL_IRQ_CONNECT(AUDIO, 5, pbl_audio_qemu_irq_handler, &s_speaker, 0);
PBL_AUDIO_HOST_MIC_DEFINE(s_mic, "mic");

---

Data Structure Documentation

pbl_audio_qemu

struct pbl_audio_qemu

QEMU audio device.

Data Fields
struct pbl_audio	audio	Audio device.
uintptr_t	base	Base address of the registers.
pbl_irq_t	irq	Interrupt.
struct pbl_audio_qemu_state *	state	Driver runtime state.

pbl_audio_host_mic

struct pbl_audio_host_mic

Host microphone.

Data Fields
struct pbl_audio	audio	Audio device.
struct pbl_audio_host_mic_state *	state	Driver runtime state.

Macro Definition Documentation

PBL_AUDIO_HOST_MIC_DEFINE

#define PBL_AUDIO_HOST_MIC_DEFINE	(		sym,
			_name
	)

Value:

  PBL_AUDIO_STATE_DEFINE(sym);                                                                    \
  static struct pbl_audio_host_mic_state sym##_host_mic_state;                                    \
  static const struct pbl_audio_host_mic sym = {                                                  \
    .audio =                                                                                      \
        PBL_AUDIO_INIT(sym, _name, PBL_AUDIO_CAPTURE, &pbl_audio_host_mic_ops, nullptr, nullptr), \
    .state = &sym##_host_mic_state,                                                               \
  };                                                                                              \
  PBL_DEVICE_REGISTER(sym, &sym.audio.dev)

Define the host microphone, a capture device.

Parameters

sym	Symbol of the device.
_name	Device name.

PBL_AUDIO_QEMU_DEFINE

#define PBL_AUDIO_QEMU_DEFINE	(		sym,
			_name,
			_base,
			_irq
	)

Value:

  PBL_AUDIO_STATE_DEFINE(sym);                                                                 \
  static struct pbl_audio_qemu_state sym##_qemu_state;                                         \
  static const struct pbl_audio_qemu sym = {                                                   \
    .audio =                                                                                   \
        PBL_AUDIO_INIT(sym, _name, PBL_AUDIO_PLAYBACK, &pbl_audio_qemu_ops, nullptr, nullptr), \
    .base = (_base),                                                                           \
    .irq = (_irq),                                                                             \
    .state = &sym##_qemu_state,                                                                \
  };                                                                                           \
  PBL_DEVICE_REGISTER(sym, &sym.audio.dev)

Define the QEMU audio device, a playback device.

Parameters

sym	Symbol of the device.
_name	Device name.
_base	Base address of the registers.
_irq	Interrupt; the board connects pbl_audio_qemu_irq_handler() to it.

Function Documentation

pbl_audio_qemu_irq_handler()

void pbl_audio_qemu_irq_handler

(

const struct pbl_audio_qemu *

dev

)

QEMU audio device interrupt handler, to connect with PBL_IRQ_CONNECT().

Parameters

dev

Device.

qemu_mic_msg_callback()

void qemu_mic_msg_callback	(	const uint8_t *	data,
		uint32_t	len
	)

Handle a QemuProtocol_MicAudio message from the host.

Queues the samples for the recording host microphone, dropping the oldest once the queue is full. Ignored while it is not recording.

Parameters

data	16 kHz mono signed 16-bit little-endian PCM.
len	Length of data in bytes.