rp2040/example/peripherals/usb/usb_device/main.c

#include "system.h"
#include "resets.h"
#include "gpio.h"
#include "timer.h"
#include "usb.h"
#include "stdio.h"

extern struct usb_device_configuration dev_config;
extern void ep0_in_handler(uint8_t *buf, uint16_t len);
extern void ep0_out_handler(uint8_t *buf, uint16_t len);

void ep1_out_handler(uint8_t *buf, uint16_t len)
{
    printf("RX %d bytes from host\n", len);
    buf[len] = 0;
    printf("received data: %s\r\n", buf);
    // Send data back to host
    struct usb_endpoint_configuration *ep = usb_get_endpoint_configuration(EP2_IN_ADDR);
    usb_start_transfer(ep, buf, len);
}

void ep2_in_handler(uint8_t *buf, uint16_t len)
{
    printf("Sent %d bytes to host\n", len);
    // Get ready to rx again from host
    usb_start_transfer(usb_get_endpoint_configuration(EP1_OUT_ADDR), NULL, 64);
}

static const struct usb_endpoint_descriptor ep0_out = {
    .bLength          = sizeof(struct usb_endpoint_descriptor),
    .bDescriptorType  = USB_DT_ENDPOINT,
    .bEndpointAddress = EP0_OUT_ADDR, // EP number 0, OUT from host (rx to device)
    .bmAttributes     = USB_TRANSFER_TYPE_CONTROL,
    .wMaxPacketSize   = 64,
    .bInterval        = 0
};

static const struct usb_endpoint_descriptor ep0_in = {
    .bLength          = sizeof(struct usb_endpoint_descriptor),
    .bDescriptorType  = USB_DT_ENDPOINT,
    .bEndpointAddress = EP0_IN_ADDR, // EP number 0, OUT from host (rx to device)
    .bmAttributes     = USB_TRANSFER_TYPE_CONTROL,
    .wMaxPacketSize   = 64,
    .bInterval        = 0
};

static const struct usb_endpoint_descriptor ep1_out = {
    .bLength          = sizeof(struct usb_endpoint_descriptor),
    .bDescriptorType  = USB_DT_ENDPOINT,
    .bEndpointAddress = EP1_OUT_ADDR, // EP number 1, OUT from host (rx to device)
    .bmAttributes     = USB_TRANSFER_TYPE_BULK,
    .wMaxPacketSize   = 64,
    .bInterval        = 0
};

static const struct usb_endpoint_descriptor ep2_in = {
    .bLength          = sizeof(struct usb_endpoint_descriptor),
    .bDescriptorType  = USB_DT_ENDPOINT,
    .bEndpointAddress = EP2_IN_ADDR, // EP number 2, IN from host (tx from device)
    .bmAttributes     = USB_TRANSFER_TYPE_BULK,
    .wMaxPacketSize   = 64,
    .bInterval        = 0
};

// Descriptors
static const struct usb_device_descriptor device_descriptor = {
    .bLength         = sizeof(struct usb_device_descriptor),
    .bDescriptorType = USB_DT_DEVICE,
    .bcdUSB          = 0x0110, // USB 1.1 device
    .bDeviceClass    = 0,      // Specified in interface descriptor
    .bDeviceSubClass = 0,      // No subclass
    .bDeviceProtocol = 0,      // No protocol
    .bMaxPacketSize0 = 64,     // Max packet size for ep0
    .idVendor        = 0x0000, // Your vendor id
    .idProduct       = 0x0001, // Your product ID
    .bcdDevice       = 0,      // No device revision number
    .iManufacturer   = 1,      // Manufacturer string index
    .iProduct        = 2,      // Product string index
    .iSerialNumber = 0,        // No serial number
    .bNumConfigurations = 1,   // One configuration
};

static const struct usb_interface_descriptor interface_descriptor = {
    .bLength            = sizeof(struct usb_interface_descriptor),
    .bDescriptorType    = USB_DT_INTERFACE,
    .bInterfaceNumber   = 0,
    .bAlternateSetting  = 0,
    .bNumEndpoints      = 2,    // Interface has 2 endpoints
    .bInterfaceClass    = 0xff, // Vendor specific endpoint
    .bInterfaceSubClass = 0,
    .bInterfaceProtocol = 0,
    .iInterface         = 0,
};

static const struct usb_configuration_descriptor config_descriptor = {
    .bLength         = sizeof(struct usb_configuration_descriptor),
    .bDescriptorType = USB_DT_CONFIG,
    .wTotalLength    = (sizeof(config_descriptor) +
                        sizeof(interface_descriptor) +
                        sizeof(ep1_out) +
                        sizeof(ep2_in)),
    .bNumInterfaces  = 1,
    .bConfigurationValue = 1, // Configuration 1
    .iConfiguration = 0,      // No string
    .bmAttributes = 0xc0,     // attributes: self powered, no remote wakeup
    .bMaxPower = 0x32         // 100ma
};

static const unsigned char lang_descriptor[] = {
    4,         // bLength
    0x03,      // bDescriptorType == String Descriptor
    0x09, 0x04 // language id = us english
};

static const unsigned char *descriptor_strings[] = {
    (unsigned char *) "Raspberry Pi",    // Vendor
    (unsigned char *) "Pico Test Device" // Product
};

// Struct defining the device configuration
struct usb_device_configuration dev_config = {
    .device_descriptor = &device_descriptor,
    .interface_descriptor = &interface_descriptor,
    .config_descriptor = &config_descriptor,
    .lang_descriptor = lang_descriptor,
    .descriptor_strings = descriptor_strings,
    .endpoints = {
            {
                    .descriptor = &ep0_out,
                    .handler = &ep0_out_handler,
                    .endpoint_control = NULL, // NA for EP0
                    .buffer_control = &usb_dpram->ep_buf_ctrl[0].out,
                    // EP0 in and out share a data buffer
                    .data_buffer = &usb_dpram->ep0_buf_a[0],
            },
            {
                    .descriptor = &ep0_in,
                    .handler = &ep0_in_handler,
                    .endpoint_control = NULL, // NA for EP0,
                    .buffer_control = &usb_dpram->ep_buf_ctrl[0].in,
                    // EP0 in and out share a data buffer
                    .data_buffer = &usb_dpram->ep0_buf_a[0],
            },
            {
                    .descriptor = &ep1_out,
                    .handler = &ep1_out_handler,
                    // EP1 starts at offset 0 for endpoint control
                    .endpoint_control = &usb_dpram->ep_ctrl[0].out,
                    .buffer_control = &usb_dpram->ep_buf_ctrl[1].out,
                    // First free EPX buffer
                    .data_buffer = &usb_dpram->epx_data[0 * 64],
            },
            {
                    .descriptor = &ep2_in,
                    .handler = &ep2_in_handler,
                    .endpoint_control = &usb_dpram->ep_ctrl[1].in,
                    .buffer_control = &usb_dpram->ep_buf_ctrl[2].in,
                    // Second free EPX buffer
                    .data_buffer = &usb_dpram->epx_data[1 * 64],
            }
    }
};

int main(void)
{
    uint64_t time_start, time_stop;

    system_init();
    usb_device_init(&dev_config);
    while (usb_is_configured() == 0);
    printf("enumed time: %ld\r\n", (uint32_t)timer_count_read());

    // Get ready to rx from host
    usb_start_transfer(usb_get_endpoint_configuration(EP1_OUT_ADDR), NULL, 64);

    time_start = timer_count_read();
    while (1) {
        time_stop = timer_count_read();
        if (time_stop - time_start > 30 * 1000 * 1000) {
            usb_hw_clear->sie_ctrl = USB_SIE_CTRL_PULLUP_EN_BITS;
            reset_unreset_blocks_wait(RESETS_BLOCK_USBCTRL);
            printf("time 1s, stop USB\r\n");
            break;
        }
    }

    return 0;
}