diff --git a/ccid/ccid_proto.h b/ccid/ccid_proto.h
new file mode 100644
index 0000000..c3c740c
--- /dev/null
+++ b/ccid/ccid_proto.h
@@ -0,0 +1,367 @@
+#pragma once
+#include <stdint.h>
+
+/* Identifies the length of type of subordinate descriptors of a CCID device
+ * Table 5.1-1 Smart Card Device Class descriptors */
+struct usb_ccid_class_descriptor {
+	uint8_t  bLength;
+	uint8_t  bDescriptorType;
+	uint16_t bcdCCID;
+	uint8_t  bMaxSlotIndex;
+	uint8_t  bVoltageSupport;
+	uint32_t dwProtocols;
+	uint32_t dwDefaultClock;
+	uint32_t dwMaximumClock;
+	uint8_t  bNumClockSupported;
+	uint32_t dwDataRate;
+	uint32_t dwMaxDataRate;
+	uint8_t  bNumDataRatesSupported;
+	uint32_t dwMaxIFSD;
+	uint32_t dwSynchProtocols;
+	uint32_t dwMechanical;
+	uint32_t dwFeatures;
+	uint32_t dwMaxCCIDMessageLength;
+	uint8_t  bClassGetResponse;
+	uint8_t  bClassEnvelope;
+	uint16_t wLcdLayout;
+	uint8_t  bPINSupport;
+	uint8_t  bMaxCCIDBusySlots;
+} __attribute__((packed));
+/* handling of bulk out from host */
+
+enum ccid_msg_type {
+	/* Section 6.3 / Table 6.3-1: Interrupt IN */
+	RDR_to_PC_NotifySlotChange		= 0x50,
+	RDR_to_PC_HardwareError			= 0x51,
+
+	/* Section 6.1 / Table 6.1-1: Bulk OUT */
+	PC_to_RDR_IccPowerOn			= 0x62,
+	PC_to_RDR_IccPowerOff			= 0x63,
+	PC_to_RDR_GetSlotStatus			= 0x65,
+	PC_to_RDR_XfrBlock			= 0x6f,
+	PC_to_RDR_GetParameters			= 0x6c,
+	PC_to_RDR_ResetParameters		= 0x6d,
+	PC_to_RDR_SetParameters			= 0x61,
+	PC_to_RDR_Escape			= 0x6b,
+	PC_to_RDR_IccClock			= 0x6e,
+	PC_to_RDR_T0APDU			= 0x6a,
+	PC_to_RDR_Secure			= 0x69,
+	PC_to_RDR_Mechanical			= 0x71,
+	PC_to_RDR_Abort				= 0x72,
+	PC_to_RDR_SetDataRateAndClockFrequency	= 0x73,
+
+	/* Section 6.2 / Table 6.2-1: Bulk IN */
+	RDR_to_PC_DataBlock			= 0x80,
+	RDR_to_PC_SlotStatus			= 0x81,
+	RDR_to_PC_Parameters			= 0x82,
+	RDR_to_PC_Escape			= 0x83,
+	RDR_to_PC_DataRateAndClockFrequency	= 0x84,
+};
+
+/* CCID message header on BULK-OUT endpoint */
+struct ccid_header {
+	uint8_t		bMessageType;
+	uint32_t	dwLength;
+	uint8_t		bSlot;
+	uint8_t		bSeq;
+} __attribute__ ((packed));
+
+/***********************************************************************
+ * Bulk OUT
+ ***********************************************************************/
+
+/* Section 6.1.1 */
+enum ccid_power_select {
+	CCID_PWRSEL_AUTO	= 0x00,
+	CCID_PWRSEL_5V0		= 0x01,
+	CCID_PWRSEL_3V0		= 0x02,
+	CCID_PWRSEL_1V8		= 0x03,
+};
+
+/* Section 6.1.1 */
+struct ccid_pc_to_rdr_icc_power_on {
+	struct ccid_header hdr;
+	uint8_t bPowerSelect;
+	uint8_t abRFU[2];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_DataBlock */
+
+/* Section 6.1.2 */
+struct ccid_pc_to_rdr_icc_power_off {
+	struct ccid_header hdr;
+	uint8_t abRFU[3];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_SlotStatus */
+
+/* Section 6.1.3 */
+struct ccid_pc_to_rdr_get_slot_status {
+	struct ccid_header hdr;
+	uint8_t abRFU[3];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_SlotStatus */
+
+/* Section 6.1.4 */
+struct ccid_pc_to_rdr_xfr_block {
+	struct ccid_header hdr;
+	uint8_t bBWI;
+	uint16_t wLevelParameter;
+	uint8_t abData[0];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_DataBlock */
+
+/* Section 6.1.5 */
+struct ccid_pc_to_rdr_get_parameters {
+	struct ccid_header hdr;
+	uint8_t abRFU[3];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_Parameters */
+
+/* Section 6.1.6 */
+struct ccid_pc_to_rdr_reset_parameters {
+	struct ccid_header hdr;
+	uint8_t abRFU[3];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_Parameters */
+
+/* Section 6.1.7 */
+struct ccid_proto_data_t0 {
+	uint8_t bmFindexDindex;
+	uint8_t bmTCCKST0;
+	uint8_t bGuardTimeT0;
+	uint8_t bWaitingIntegerT0;
+	uint8_t bClockStop;
+} __attribute__ ((packed));
+struct ccid_proto_data_t1 {
+	uint8_t bmFindexDindex;
+	uint8_t bmTCCKST1;
+	uint8_t bGuardTimeT1;
+	uint8_t bWaitingIntegersT1;
+	uint8_t bClockStop;
+	uint8_t bFSC;
+	uint8_t bNadValue;
+} __attribute__ ((packed));
+struct ccid_pc_to_rdr_set_parameters {
+	struct ccid_header hdr;
+	uint8_t bProtocolNum;
+	uint8_t abRFU[2];
+	union {
+		struct ccid_proto_data_t0 t0;
+		struct ccid_proto_data_t1 t1;
+	} abProtocolData;
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_Parameters */
+
+/* Section 6.1.8 */
+struct ccid_pc_to_rdr_escape {
+	struct ccid_header hdr;
+	uint8_t abRFU[3];
+	uint8_t abData[0];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_Escape */
+
+/* Section 6.1.9 */
+enum ccid_clock_command {
+	CCID_CLOCK_CMD_RESTART		= 0x00,
+	CCID_CLOCK_CMD_STOP		= 0x01,
+};
+struct ccid_pc_to_rdr_icc_clock {
+	struct ccid_header hdr;
+	uint8_t bClockCommand;
+	uint8_t abRFU[2];
+} __attribute__ ((packed));
+/* response: RDR_to_PC_SlotStatus */
+
+/* Section 6.1.10 */
+struct ccid_pc_to_rdr_t0apdu {
+	struct ccid_header hdr;
+	uint8_t bmChanges;
+	uint8_t bClassGetResponse;
+	uint8_t bClassEnvelope;
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_SlotStatus */
+
+/* Section 6.1.11 */
+struct ccid_pc_to_rdr_secure {
+	struct ccid_header hdr;
+	uint8_t bBWI;
+	uint16_t wLevelParameter;
+	uint8_t abData[0];
+} __attribute__ ((packed));
+struct ccid_pin_operation_data {
+	uint8_t bPINOperation;
+	uint8_t abPNDataStructure[0];
+} __attribute__ ((packed));
+struct ccid_pin_verification_data {
+	uint8_t bTimeOut;
+	uint8_t bmFormatString;
+	uint8_t bmPINBlockString;
+	uint8_t bmPINLengthFormat;
+	uint16_t wPINMaxExtraDigit;
+	uint8_t bEntryValidationCondition;
+	uint8_t bNumberMessage;
+	uint16_t wLangId;
+	uint8_t bMsgIndex;
+	uint8_t bTecPrologue;
+	uint8_t abPINApdu[0];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_DataBlock */
+
+/* Section 6.1.12 */
+struct ccid_pc_to_rdr_mechanical {
+	struct ccid_header hdr;
+	uint8_t bFunction; /* ccid_mech_function */
+	uint8_t abRFU[2];
+} __attribute__ ((packed));
+enum ccid_mech_function {
+	CCID_MECH_FN_ACCEPT_CARD	= 0x01,
+	CCID_MECH_FN_EJECT_CARD		= 0x02,
+	CCID_MECH_FN_CAPTURE_CARD	= 0x03,
+	CCID_MECH_FN_LOCK_CARD		= 0x04,
+	CCID_MECH_FN_UNLOCK_CARD	= 0x05,
+};
+/* Response: RDR_to_PC_SlotStatus */
+
+/* Section 6.1.13 */
+struct ccid_pc_to_rdr_abort {
+	struct ccid_header hdr;
+	uint8_t abRFU[3];
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_SlotStatus */
+
+/* Section 6.1.14 */
+struct ccid_pc_to_rdr_set_rate_and_clock {
+	struct ccid_header hdr;
+	uint8_t abRFU[3];
+	uint32_t dwClockFrequency;
+	uint32_t dwDataRate;
+} __attribute__ ((packed));
+/* Response: RDR_to_PC_DataRateAndClockFrequency */
+
+union ccid_pc_to_rdr {
+	struct ccid_pc_to_rdr_icc_power_on		icc_power_on;
+	struct ccid_pc_to_rdr_icc_power_off		icc_power_off;
+	struct ccid_pc_to_rdr_get_slot_status		get_slot_status;
+	struct ccid_pc_to_rdr_xfr_block			xfr_block;
+	struct ccid_pc_to_rdr_get_parameters		get_parameters;
+	struct ccid_pc_to_rdr_reset_parameters		reset_parameters;
+	struct ccid_pc_to_rdr_set_parameters		set_parameters;
+	struct ccid_pc_to_rdr_escape			escape;
+	struct ccid_pc_to_rdr_icc_clock			icc_clock;
+	struct ccid_pc_to_rdr_t0apdu			t0apdu;
+	struct ccid_pc_to_rdr_secure			secure;
+	struct ccid_pc_to_rdr_mechanical		mechanical;
+	struct ccid_pc_to_rdr_abort			abort;
+	struct ccid_pc_to_rdr_set_rate_and_clock	set_rate_and_clock;
+};
+
+/***********************************************************************
+ * Bulk IN
+ ***********************************************************************/
+
+/* CCID message header on BULK-IN endpoint */
+struct ccid_header_in {
+	struct ccid_header hdr;
+	uint8_t		bStatus;
+	uint8_t		bError;
+} __attribute__ ((packed));
+
+/* Section 6.2.1 RDR_to_PC_DataBlock */
+struct ccid_rdr_to_pc_data_block {
+	struct ccid_header_in hdr;
+	uint8_t bChainParameter;
+	uint8_t abData[0];
+} __attribute__ ((packed));
+
+/* Section 6.2.2 RDR_to_PC_SlotStatus */
+struct ccid_rdr_to_pc_slot_status {
+	struct ccid_header_in hdr;
+	uint8_t bClockStatus;
+} __attribute__ ((packed));
+enum ccid_clock_status {
+	CCID_CLOCK_STATUS_RUNNING	= 0x00,
+	CCID_CLOCK_STATUS_STOPPED_L	= 0x01,
+	CCID_CLOCK_STATUS_STOPPED_H	= 0x02,
+	CCID_CLOCK_STATUS_STOPPED_UNKN	= 0x03,
+};
+
+/* Section 6.2.3 RDR_to_PC_Parameters */
+struct ccid_rdr_to_pc_parameters {
+	struct ccid_header_in hdr;
+	union {
+		struct ccid_proto_data_t0 t0;
+		struct ccid_proto_data_t1 t1;
+	} abProtocolData;
+} __attribute__ ((packed));
+
+/* Section 6.2.4 RDR_to_PC_Escape */
+struct ccid_rdr_to_pc_escape {
+	struct ccid_header hdr;
+	uint8_t bRFU;
+	uint8_t abData[0];
+} __attribute__ ((packed));
+
+/* Section 6.2.5 RDR_to_PC_DataRateAndClockFrequency */
+struct ccid_rdr_to_pc_data_rate_and_clock {
+	struct ccid_header hdr;
+	uint8_t bRFU;
+	uint32_t dwClockFrequency;
+	uint32_t dwDataRate;
+} __attribute__ ((packed));
+
+/* Section 6.2.6 */
+#define CCID_ICC_STATUS_MASK		0x03
+#define CCID_ICC_STATUS_PRES_ACT	0x00
+#define CCID_ICC_STATUS_PRES_INACT	0x01
+#define CCID_ICC_STATUS_NO_ICC		0x02
+#define CCID_CMD_STATUS_MASK		0xC0
+#define CCID_CMD_STATUS_OK		0x00
+#define CCID_CMD_STATUS_FAILED		0x40
+#define CCID_CMD_STATUS_TIME_EXT	0x80
+/* Table 6.2-2: Slot Error value when bmCommandStatus == 1 */
+enum ccid_error_code {
+	CCID_ERR_CMD_ABORTED			= 0xff,
+	CCID_ERR_ICC_MUTE			= 0xfe,
+	CCID_ERR_XFR_PARITY_ERROR		= 0xfd,
+	CCID_ERR_XFR_OVERRUN			= 0xfc,
+	CCID_ERR_HW_ERROR			= 0xfb,
+	CCID_ERR_BAD_ATR_TS			= 0xf8,
+	CCID_ERR_BAD_ATR_TCK			= 0xf7,
+	CCID_ERR_ICC_PROTOCOL_NOT_SUPPORTED	= 0xf6,
+	CCID_ERR_ICC_CLASS_NOT_SUPPORTED	= 0xf5,
+	CCID_ERR_PROCEDURE_BYTE_CONFLICT	= 0xf4,
+	CCID_ERR_DEACTIVATED_PROTOCOL		= 0xf3,
+	CCID_ERR_BUSY_WITH_AUTO_SEQUENCE	= 0xf2,
+	CCID_ERR_PIN_TIMEOUT			= 0xf0,
+	CCID_ERR_PIN_CANCELLED			= 0xef,
+	CCID_ERR_CMD_SLOT_BUSY			= 0xe0,
+	CCID_ERR_CMD_NOT_SUPPORTED		= 0x00
+};
+
+union ccid_rdr_to_pc {
+	struct ccid_rdr_to_pc_data_block		data_block;
+	struct ccid_rdr_to_pc_slot_status		slot_status;
+	struct ccid_rdr_to_pc_parameters		parameters;
+	struct ccid_rdr_to_pc_escape			escape;
+	struct ccid_rdr_to_pc_data_rate_and_clock	rate_and_clock;
+};
+
+/***********************************************************************
+ * Interupt IN
+ ***********************************************************************/
+
+/* Section 6.3.1 */
+struct ccid_rdr_to_pc_notify_slot_change {
+	uint8_t bMessageType;
+	uint8_t bmSlotCCState[0];	/* as long as bNumSlots/4 padded to next byte */
+} __attribute__ ((packed));
+
+/* Section 6.3.1 */
+struct ccid_rdr_to_pc_hardware_error {
+	struct ccid_header hdr;
+	uint8_t bHardwareErrorCode;
+} __attribute__ ((packed));
+
+union ccid_rdr_to_pc_irq {
+	struct ccid_rdr_to_pc_notify_slot_change	slot_change;
+	struct ccid_rdr_to_pc_hardware_error		hw_error;
+};