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#include <rcc/rcc.h>
#include <gpio/pin.h>
#include <os/time.h>
#include <usb/usb.h>
#include <usb/descriptor.h>
#include <spi/spi.h>
#include <dma/dma.h>
#include <i2c/i2c.h>
Pin& dac_nreset = PD4;
Pin& i2c_scl = PB6;
Pin& i2c_sda = PB9;
Pin& i2s_mck = PC7;
Pin& i2s_sck = PC10;
Pin& i2s_sd = PC12;
Pin& i2s_ws = PA4;
Pin& usb_vbus = PA9;
Pin& usb_dm = PA11;
Pin& usb_dp = PA12;
const uint32_t audio_buf_size = 1024;
uint16_t audio_buf[audio_buf_size];
uint32_t audio_buf_pos = 0;
struct AS_General_desc {
uint8_t bLength;
uint8_t bDescriptorType;
uint8_t bDescriptorSubType;
uint8_t bTerminalLink;
uint8_t bDelay;
uint16_t wFormatTag;
} __attribute__((packed));
constexpr AS_General_desc as_general_desc(
uint8_t bTerminalLink,
uint8_t bDelay,
uint16_t wFormatTag
) {
return {
sizeof(AS_General_desc),
0x24,
0x01,
bTerminalLink,
bDelay,
wFormatTag
};
}
template <uint32_t S>
struct foo_t {
uint8_t a[S];
} __attribute__((packed));
const foo_t<43> acd = {{
9, 36, 1, 0,1, 43,0, 1, 1,
12, 36, 2, 1, 1,1, 0, 2, 3,0, 0, 0,
13, 36, 6, 13, 1, 2, 1, 2, 2, 0, 2, 0, 0,
9, 36, 3, 3, 1,3, 0, 13, 0
}};
const foo_t<11> asfd = {{11, 36, 2, 1, 2, 2, 16, 1, 48000 & 0xff, (48000 >> 8) & 0xff, 48000 >> 16}};
const foo_t<7> aced = {{7, 37, 1, 1, 0, 0, 0}};
auto dev_desc = device_desc(0x200, 0, 0, 0, 64, 0x1234, 0x5678, 0, 0, 0, 0, 1);
auto conf_desc = configuration_desc(2, 1, 0, 0xc0, 0,
// AudioControl
interface_desc(0, 0, 0, 0x01, 0x01, 0x00, 0,
acd
),
// AudioStreaming
interface_desc(1, 0, 0, 0x01, 0x02, 0x00, 0),
interface_desc(1, 1, 1, 0x01, 0x02, 0x00, 0,
as_general_desc(1, 1, 1),
asfd,
endpoint_desc(0x01, 0x09, 256, 1),
aced
)
);
class DAC {
Pin& nreset;
I2C& i2c;
public:
DAC(Pin& _nreset, I2C& _i2c) : nreset(_nreset), i2c(_i2c) {}
void init() {
// Configure CS43L22.
nreset.set_mode(Pin::Output);
nreset.on();
i2c.write_reg(0x4a, 0x02, 0x9e);
i2c.write_reg(0x4a, 0x06, (0 << 7) | (1 << 6) | (0 << 4) | (1 << 2) | (3 << 0));
}
uint8_t get_volume(uint8_t c) {
uint8_t buf;
i2c.read_reg(0x4a, 0x1a + c, 1, &buf);
return ((buf & 0x7f) - 0x19) & 0x7f;
}
void set_volume(uint8_t c, uint8_t v) {
i2c.write_reg(0x4a, 0x1a + c, (v + 0x19) & 0x7f);
}
};
DAC dac(dac_nreset, I2C1);
desc_t dev_desc_p = {sizeof(dev_desc), (void*)&dev_desc};
desc_t conf_desc_p = {sizeof(conf_desc), (void*)&conf_desc};
USB_otg usb(OTG_FS, dev_desc_p, conf_desc_p);
class USB_Audio : public USB_class_driver {
private:
USB_generic& usb;
enum ControlState {None, VolLeft, VolRight};
ControlState control_state;
public:
USB_Audio(USB_generic& usbd) : usb(usbd) {
usb.register_driver(this);
}
protected:
virtual SetupStatus handle_setup(uint8_t bmRequestType, uint8_t bRequest, uint16_t wValue, uint16_t wIndex, uint16_t wLength) {
control_state = ControlState::None;
// GET_CUR
if(bmRequestType == 0xa1 && bRequest == 0x81) {
uint32_t res = 0;
usb.write(0, &res, wLength);
return SetupStatus::Ok;
}
// GET_MIN
if(bmRequestType == 0xa1 && bRequest == 0x82) {
uint32_t res = 0;
usb.write(0, &res, wLength);
return SetupStatus::Ok;
}
// GET_MAX
if(bmRequestType == 0xa1 && bRequest == 0x83) {
uint32_t res = 127;
usb.write(0, &res, wLength);
return SetupStatus::Ok;
}
// GET_RES
if(bmRequestType == 0xa1 && bRequest == 0x84) {
uint32_t res = 1;
usb.write(0, &res, wLength);
return SetupStatus::Ok;
}
// SET_CUR
if(bmRequestType == 0x21 && bRequest == 0x01) {
switch(wValue) {
case 0x0201:
control_state = ControlState::VolLeft;
break;
case 0x0202:
control_state = ControlState::VolRight;
break;
}
return SetupStatus::Ok;
}
// SET_CUR
if(bmRequestType == 0x22 && bRequest == 0x01) {
return SetupStatus::Ok;
}
return SetupStatus::Unhandled;
}
virtual void handle_set_configuration(uint8_t configuration) {
if(configuration) {
usb.register_out_handler(this, 1);
usb.hw_conf_ep(0x01, EPType::Isochronous, 256);
}
}
virtual void handle_out(uint8_t ep, uint32_t len) {
if(ep == 0 && len > 0) {
uint32_t buf;
usb.read(0, &buf, len > 4 ? 4 : len);
switch(control_state) {
case ControlState::VolLeft:
dac.set_volume(0, buf & 0xff);
break;
case ControlState::VolRight:
dac.set_volume(1, buf & 0xff);
break;
default:
break;
}
usb.write(0, nullptr, 0);
} else if(ep == 1) {
usb_rblog.log("Received audio frame with %d bytes.", len);
if(audio_buf_pos + (len >> 1) >= audio_buf_size) {
usb.read(1, (uint32_t*)&audio_buf[audio_buf_pos], (audio_buf_size - audio_buf_pos) << 1);
len -= (audio_buf_size - audio_buf_pos) << 1;
audio_buf_pos = 0;
}
if(len) {
usb.read(1, (uint32_t*)&audio_buf[audio_buf_pos], len);
audio_buf_pos += len >> 1;
}
}
}
};
USB_Audio usb_audio(usb);
int main() {
// Initialize system timer.
STK.LOAD = 168000000 / 8 / 1000; // 1000 Hz.
STK.CTRL = 0x03;
RCC.enable(RCC.GPIOA);
RCC.enable(RCC.GPIOB);
RCC.enable(RCC.GPIOC);
RCC.enable(RCC.GPIOD);
// Initialize I2S.
i2s_mck.set_mode(Pin::AF);
i2s_mck.set_af(6);
i2s_sck.set_mode(Pin::AF);
i2s_sck.set_af(6);
i2s_sd.set_mode(Pin::AF);
i2s_sd.set_af(6);
i2s_ws.set_mode(Pin::AF);
i2s_ws.set_af(6);
RCC.PLLI2SCFGR = (3 << 28) | (258 << 6);
RCC.CR |= 1 << 26;
while(!(RCC.CR & (1 << 27)));
RCC.enable(RCC.SPI3);
SPI3.reg.I2SPR = 0x303;
SPI3.reg.I2SCFGR = 0xe00;
SPI3.reg.CR2 = 2;
// Initialize DMA.
RCC.enable(RCC.DMA1);
DMA1.reg.S[7].CR = (0 << 25) | (1 << 13) | (1 << 11) | (1 << 10) | (1 << 8) | (1 << 6);
DMA1.reg.S[7].PAR = uint32_t(&SPI3.reg.DR);
DMA1.reg.S[7].M0AR = uint32_t(&audio_buf);
DMA1.reg.S[7].NDTR = audio_buf_size;
DMA1.reg.S[7].CR |= 1;
// Initialize I2C.
I2C1.enable(i2c_scl, i2c_sda);
dac.init();
// Initialize USB.
usb_vbus.set_mode(Pin::Input);
usb_dm.set_mode(Pin::AF);
usb_dm.set_af(10);
usb_dp.set_mode(Pin::AF);
usb_dp.set_af(10);
RCC.enable(RCC.OTGFS);
usb.set_rxfifo_size(512);
usb.init();
while(1) {
usb.process();
}
}
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