firmware/right/src/usb_interface_keyboard.c

#include "fsl_port.h"
#include "usb_api.h"
#include "usb_composite_device.h"
#include "test_led.h"
#include "key_matrix.h"
#include "fsl_i2c.h"
#include "i2c.h"
#include "i2c_addresses.h"
#include "default_layout.h"

static usb_device_endpoint_struct_t UsbKeyboardEndpoints[USB_KEYBOARD_ENDPOINT_COUNT] = {{
    USB_KEYBOARD_ENDPOINT_INDEX | (USB_IN << USB_DESCRIPTOR_ENDPOINT_ADDRESS_DIRECTION_SHIFT),
    USB_ENDPOINT_INTERRUPT,
    USB_KEYBOARD_INTERRUPT_IN_PACKET_SIZE,
}};

static usb_device_interface_struct_t UsbKeyboardInterface[] = {{
    USB_INTERFACE_ALTERNATE_SETTING_NONE,
    {USB_KEYBOARD_ENDPOINT_COUNT, UsbKeyboardEndpoints},
    NULL,
}};

static usb_device_interfaces_struct_t UsbKeyboardInterfaces[USB_KEYBOARD_INTERFACE_COUNT] = {{
    USB_CLASS_HID,
    USB_HID_SUBCLASS_BOOT,
    USB_HID_PROTOCOL_KEYBOARD,
    USB_KEYBOARD_INTERFACE_INDEX,
    UsbKeyboardInterface,
    sizeof(UsbKeyboardInterface) / sizeof(usb_device_interfaces_struct_t),
}};

static usb_device_interface_list_t UsbKeyboardInterfaceList[USB_DEVICE_CONFIGURATION_COUNT] = {{
    USB_KEYBOARD_INTERFACE_COUNT,
    UsbKeyboardInterfaces,
}};

usb_device_class_struct_t UsbKeyboardClass = {
    UsbKeyboardInterfaceList,
    kUSB_DeviceClassTypeHid,
    USB_DEVICE_CONFIGURATION_COUNT,
};

volatile static int activeLayout=0;
static usb_keyboard_report_t UsbKeyboardReport[2];

#define KEYBOARD_MATRIX_COLS_NUM 7
#define KEYBOARD_MATRIX_ROWS_NUM 5

key_matrix_t keyMatrix = {
    .colNum = KEYBOARD_MATRIX_COLS_NUM,
    .rowNum = KEYBOARD_MATRIX_ROWS_NUM,
    .cols = (key_matrix_pin_t[]){
        {PORTA, GPIOA, kCLOCK_PortA, 5},
        {PORTB, GPIOB, kCLOCK_PortB, 3},
        {PORTB, GPIOB, kCLOCK_PortB, 16},
        {PORTB, GPIOB, kCLOCK_PortB, 17},
        {PORTB, GPIOB, kCLOCK_PortB, 18},
        {PORTA, GPIOA, kCLOCK_PortA, 1},
        {PORTB, GPIOB, kCLOCK_PortB, 0}
        },
    .rows = (key_matrix_pin_t[]){
        {PORTA, GPIOA, kCLOCK_PortA, 12},
        {PORTA, GPIOA, kCLOCK_PortA, 13},
        {PORTC, GPIOC, kCLOCK_PortC, 0},
        {PORTB, GPIOB, kCLOCK_PortB, 19},
        {PORTD, GPIOD, kCLOCK_PortD, 6}
    }
};

void readLeftKeys(uint8_t *stateVector){
	uint8_t data[] = {0};
	uint8_t success=0;

	if (I2cWrite(I2C_MAIN_BUS_BASEADDR, I2C_ADDRESS_LEFT_KEYBOARD_HALF, data, sizeof(data)) == kStatus_Success) {
		if (I2cRead(I2C_MAIN_BUS_BASEADDR, I2C_ADDRESS_LEFT_KEYBOARD_HALF, stateVector, KEY_STATE_COUNT) == kStatus_Success) {
			success = 1;
		}
	}

	if (!success) {
		bzero(stateVector, KEY_STATE_COUNT);
	}
}

void usbKeyboadTask(){
	//Producer task for USB packets. When the USB interrupt is called,
	//the newest packet is sent out immediately, thus not doing long task
	//in the interrupt handler.
	int newLayout = 1-activeLayout;

	static uint8_t leftKeyStates[KEY_STATE_COUNT];

	UsbKeyboardReport[newLayout].modifiers = 0;
	UsbKeyboardReport[newLayout].reserved = 0;

	KeyMatrix_Init(&keyMatrix);
	KeyMatrix_Scan(&keyMatrix);

	bzero(&UsbKeyboardReport[newLayout].scancodes, USB_KEYBOARD_MAX_KEYS*sizeof(UsbKeyboardReport[newLayout].scancodes[0]));

	readLeftKeys(leftKeyStates);

	fillKeyboardReport(&UsbKeyboardReport[newLayout], leftKeyStates, keyMatrix.keyStates, defaultKeyboardLayout);

	//Change to the new layout in atomic operation (int copy). Even if
	//the copy is not atomic itself, only single bit changes. So it can
	//never be a problem
	activeLayout = newLayout;
}


static usb_status_t UsbKeyboardAction(void)
{
    return USB_DeviceHidSend(UsbCompositeDevice.keyboardHandle, USB_KEYBOARD_ENDPOINT_INDEX,
                             (uint8_t*)&UsbKeyboardReport[activeLayout], USB_KEYBOARD_REPORT_LENGTH);
}

usb_status_t UsbKeyboardCallback(class_handle_t handle, uint32_t event, void *param)
{
    usb_status_t error = kStatus_USB_Error;

    switch (event) {
        case kUSB_DeviceHidEventSendResponse:
            if (UsbCompositeDevice.attach) {
                return UsbKeyboardAction();
            }
            break;
        case kUSB_DeviceHidEventGetReport:
        case kUSB_DeviceHidEventSetReport:
        case kUSB_DeviceHidEventRequestReportBuffer:
            error = kStatus_USB_InvalidRequest;
            break;
        case kUSB_DeviceHidEventGetIdle:
        case kUSB_DeviceHidEventGetProtocol:
        case kUSB_DeviceHidEventSetIdle:
        case kUSB_DeviceHidEventSetProtocol:
            break;
        default:
            break;
    }

    return error;
}

usb_status_t UsbKeyboardSetConfiguration(class_handle_t handle, uint8_t configuration)
{
    if (USB_COMPOSITE_CONFIGURATION_INDEX == configuration) {
        return UsbKeyboardAction();
    }
    return kStatus_USB_Error;
}

usb_status_t UsbKeyboardSetInterface(class_handle_t handle, uint8_t interface, uint8_t alternateSetting)
{
    if (USB_KEYBOARD_INTERFACE_INDEX == interface) {
        return UsbKeyboardAction();
    }
    return kStatus_USB_Error;
}