/**
* Gets the configuration descriptor of a USB device as a byte array.
* @param device USB device
* @param conf configuration number
* @param length length of the data buffer. This method will not write beyond this boundary.
* @return number of bytes read, or negative number in case of error.
*/
int usb_getConfigurationDescriptor(usb_device * device, uint8_t conf, uint16_t length, uint8_t * data)
{
uint16_t descriptorLength;
int rcode;
// Read the length of the configuration descriptor.
rcode = (usb_controlRequest(device, bmREQ_GET_DESCR, USB_REQUEST_GET_DESCRIPTOR, conf, USB_DESCRIPTOR_CONFIGURATION, 0x0000, 4, data));
if (rcode) return -1;
descriptorLength = (data[3] << 8) | data[2];
if (descriptorLength<length) length = descriptorLength;
// Read the length of the configuration descriptor.
rcode = (usb_controlRequest(device, bmREQ_GET_DESCR, USB_REQUEST_GET_DESCRIPTOR, conf, USB_DESCRIPTOR_CONFIGURATION, 0x0000, length, data));
if (rcode) return -2;
return length;
}
/**
* Convenience method for getting a string. This is useful for printing manufacturer names, serial numbers, etc.
* Language is defaulted to zero. Strings are returned in 16-bit unicode from the device, so this function converts the
* result to ASCII by ignoring every second byte. However, since the target buffer is used as a temporary storage during
* this process it must be twice as large as the desired maximum string size.
*
* @param device USB device.
* @param index string index.
* @param languageId language ID.
* @param length buffer length.
* @param str target buffer.
* @return 0 on success, error code otherwise.
*/
int usb_getString(usb_device * device, uint8_t index, uint8_t languageId, uint16_t length, char * str)
{
uint8_t stringLength = 0;
int i, ret = 0;
// Get string length;
ret = usb_controlRequest(device, bmREQ_GET_DESCR, USB_REQUEST_GET_DESCRIPTOR, index, USB_DESCRIPTOR_STRING, languageId, sizeof(uint8_t), &stringLength);
if (ret<0) return -1;
// Trim string size to fit the target buffer.
if (stringLength>length) stringLength = length;
// Get the whole thing.
ret = usb_controlRequest(device, bmREQ_GET_DESCR, USB_REQUEST_GET_DESCRIPTOR, index, USB_DESCRIPTOR_STRING, languageId, stringLength, (uint8_t *)str);
if (ret<0) return -2;
// Convert to 8-bit ASCII
stringLength = (stringLength - 2) / 2;
for (i=0; i<stringLength; i++) str[i] = str[2+i*2];
str[stringLength] = 0;
return 0;
}
//set configuration
int usb_setConfiguration(usb_device * device, uint8_t configuration)
{
return(usb_controlRequest(device, bmREQ_SET, USB_REQUEST_SET_CONFIGURATION, configuration, 0x00, 0x0000, 0x0000, NULL));
}
/**
* Sets the address of a newly connected USB device.
*
* @param device the 'zero' usb device (address 0, endpoint 0)
* @param address the address to set for the newly connected device
* @return 0 in case of success, error code otherwise
*/
int usb_setAddress(usb_device * device, uint8_t address)
{
return(usb_controlRequest(device, bmREQ_SET, USB_REQUEST_SET_ADDRESS, address, 0x00, 0x0000, 0x0000, NULL));
}
/**
* Gets the device descriptor of a USB device.
* @param device USB device
* @param descriptor pointer to a usb_deviceDescriptor record that will be filled with the requested data.
* @return 0 in case of success, error code otherwise
*/
int usb_getDeviceDescriptor(usb_device * device, usb_deviceDescriptor * descriptor)
{
return(usb_controlRequest(device, bmREQ_GET_DESCR, USB_REQUEST_GET_DESCRIPTOR, 0x00, USB_DESCRIPTOR_DEVICE, 0x0000, sizeof(usb_deviceDescriptor), (uint8_t *)descriptor));
}
/**
* Sets the HID protocol not to report until an event occurs i.e set to idle.
*/
static void hid_setIdle(usb_device * device)
{
usb_controlRequest(device, bmREQ_HIDOUT, HID_REQUEST_SET_IDLE, 0x00, 0x00, 0x0000, 0x0000, NULL);
}
