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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/usb/serial/ftdi_sio.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/serial/ftdi_sio.h')
-rw-r--r--drivers/usb/serial/ftdi_sio.h579
1 files changed, 579 insertions, 0 deletions
diff --git a/drivers/usb/serial/ftdi_sio.h b/drivers/usb/serial/ftdi_sio.h
new file mode 100644
index 0000000000..55ea61264f
--- /dev/null
+++ b/drivers/usb/serial/ftdi_sio.h
@@ -0,0 +1,579 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Driver definitions for the FTDI USB Single Port Serial Converter -
+ * known as FTDI_SIO (Serial Input/Output application of the chipset)
+ *
+ * For USB vendor/product IDs (VID/PID), please see ftdi_sio_ids.h
+ *
+ *
+ * The example I have is known as the USC-1000 which is available from
+ * http://www.dse.co.nz - cat no XH4214 It looks similar to this:
+ * http://www.dansdata.com/usbser.htm but I can't be sure There are other
+ * USC-1000s which don't look like my device though so beware!
+ *
+ * The device is based on the FTDI FT8U100AX chip. It has a DB25 on one side,
+ * USB on the other.
+ *
+ * Thanx to FTDI (http://www.ftdichip.com) for so kindly providing details
+ * of the protocol required to talk to the device and ongoing assistence
+ * during development.
+ *
+ * Bill Ryder - bryder@sgi.com formerly of Silicon Graphics, Inc.- wrote the
+ * FTDI_SIO implementation.
+ *
+ */
+
+/* Commands */
+#define FTDI_SIO_RESET 0 /* Reset the port */
+#define FTDI_SIO_MODEM_CTRL 1 /* Set the modem control register */
+#define FTDI_SIO_SET_FLOW_CTRL 2 /* Set flow control register */
+#define FTDI_SIO_SET_BAUD_RATE 3 /* Set baud rate */
+#define FTDI_SIO_SET_DATA 4 /* Set the data characteristics of
+ the port */
+#define FTDI_SIO_GET_MODEM_STATUS 5 /* Retrieve current value of modem
+ status register */
+#define FTDI_SIO_SET_EVENT_CHAR 6 /* Set the event character */
+#define FTDI_SIO_SET_ERROR_CHAR 7 /* Set the error character */
+#define FTDI_SIO_SET_LATENCY_TIMER 9 /* Set the latency timer */
+#define FTDI_SIO_GET_LATENCY_TIMER 0x0a /* Get the latency timer */
+#define FTDI_SIO_SET_BITMODE 0x0b /* Set bitbang mode */
+#define FTDI_SIO_READ_PINS 0x0c /* Read immediate value of pins */
+#define FTDI_SIO_READ_EEPROM 0x90 /* Read EEPROM */
+
+/* Channel indices for FT2232, FT2232H and FT4232H devices */
+#define CHANNEL_A 1
+#define CHANNEL_B 2
+#define CHANNEL_C 3
+#define CHANNEL_D 4
+
+
+/*
+ * BmRequestType: 1100 0000b
+ * bRequest: FTDI_E2_READ
+ * wValue: 0
+ * wIndex: Address of word to read
+ * wLength: 2
+ * Data: Will return a word of data from E2Address
+ *
+ */
+
+/* Port Identifier Table */
+#define PIT_DEFAULT 0 /* SIOA */
+#define PIT_SIOA 1 /* SIOA */
+/* The device this driver is tested with one has only one port */
+#define PIT_SIOB 2 /* SIOB */
+#define PIT_PARALLEL 3 /* Parallel */
+
+/* FTDI_SIO_RESET */
+#define FTDI_SIO_RESET_REQUEST FTDI_SIO_RESET
+#define FTDI_SIO_RESET_REQUEST_TYPE 0x40
+#define FTDI_SIO_RESET_SIO 0
+#define FTDI_SIO_RESET_PURGE_RX 1
+#define FTDI_SIO_RESET_PURGE_TX 2
+
+/*
+ * BmRequestType: 0100 0000B
+ * bRequest: FTDI_SIO_RESET
+ * wValue: Control Value
+ * 0 = Reset SIO
+ * 1 = Purge RX buffer
+ * 2 = Purge TX buffer
+ * wIndex: Port
+ * wLength: 0
+ * Data: None
+ *
+ * The Reset SIO command has this effect:
+ *
+ * Sets flow control set to 'none'
+ * Event char = $0D
+ * Event trigger = disabled
+ * Purge RX buffer
+ * Purge TX buffer
+ * Clear DTR
+ * Clear RTS
+ * baud and data format not reset
+ *
+ * The Purge RX and TX buffer commands affect nothing except the buffers
+ *
+ */
+
+/* FTDI_SIO_SET_BAUDRATE */
+#define FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE 0x40
+#define FTDI_SIO_SET_BAUDRATE_REQUEST 3
+
+/*
+ * BmRequestType: 0100 0000B
+ * bRequest: FTDI_SIO_SET_BAUDRATE
+ * wValue: BaudDivisor value - see below
+ * wIndex: Port
+ * wLength: 0
+ * Data: None
+ * The BaudDivisor values are calculated as follows:
+ * - BaseClock is either 12000000 or 48000000 depending on the device.
+ * FIXME: I wish I knew how to detect old chips to select proper base clock!
+ * - BaudDivisor is a fixed point number encoded in a funny way.
+ * (--WRONG WAY OF THINKING--)
+ * BaudDivisor is a fixed point number encoded with following bit weighs:
+ * (-2)(-1)(13..0). It is a radical with a denominator of 4, so values
+ * end with 0.0 (00...), 0.25 (10...), 0.5 (01...), and 0.75 (11...).
+ * (--THE REALITY--)
+ * The both-bits-set has quite different meaning from 0.75 - the chip
+ * designers have decided it to mean 0.125 instead of 0.75.
+ * This info looked up in FTDI application note "FT8U232 DEVICES \ Data Rates
+ * and Flow Control Consideration for USB to RS232".
+ * - BaudDivisor = (BaseClock / 16) / BaudRate, where the (=) operation should
+ * automagically re-encode the resulting value to take fractions into
+ * consideration.
+ * As all values are integers, some bit twiddling is in order:
+ * BaudDivisor = (BaseClock / 16 / BaudRate) |
+ * (((BaseClock / 2 / BaudRate) & 4) ? 0x4000 // 0.5
+ * : ((BaseClock / 2 / BaudRate) & 2) ? 0x8000 // 0.25
+ * : ((BaseClock / 2 / BaudRate) & 1) ? 0xc000 // 0.125
+ * : 0)
+ *
+ * For the FT232BM, a 17th divisor bit was introduced to encode the multiples
+ * of 0.125 missing from the FT8U232AM. Bits 16 to 14 are coded as follows
+ * (the first four codes are the same as for the FT8U232AM, where bit 16 is
+ * always 0):
+ * 000 - add .000 to divisor
+ * 001 - add .500 to divisor
+ * 010 - add .250 to divisor
+ * 011 - add .125 to divisor
+ * 100 - add .375 to divisor
+ * 101 - add .625 to divisor
+ * 110 - add .750 to divisor
+ * 111 - add .875 to divisor
+ * Bits 15 to 0 of the 17-bit divisor are placed in the urb value. Bit 16 is
+ * placed in bit 0 of the urb index.
+ *
+ * Note that there are a couple of special cases to support the highest baud
+ * rates. If the calculated divisor value is 1, this needs to be replaced with
+ * 0. Additionally for the FT232BM, if the calculated divisor value is 0x4001
+ * (1.5), this needs to be replaced with 0x0001 (1) (but this divisor value is
+ * not supported by the FT8U232AM).
+ */
+
+enum ftdi_sio_baudrate {
+ ftdi_sio_b300 = 0,
+ ftdi_sio_b600 = 1,
+ ftdi_sio_b1200 = 2,
+ ftdi_sio_b2400 = 3,
+ ftdi_sio_b4800 = 4,
+ ftdi_sio_b9600 = 5,
+ ftdi_sio_b19200 = 6,
+ ftdi_sio_b38400 = 7,
+ ftdi_sio_b57600 = 8,
+ ftdi_sio_b115200 = 9
+};
+
+/*
+ * The ftdi_8U232AM_xxMHz_byyy constants have been removed. The encoded divisor
+ * values are calculated internally.
+ */
+#define FTDI_SIO_SET_DATA_REQUEST FTDI_SIO_SET_DATA
+#define FTDI_SIO_SET_DATA_REQUEST_TYPE 0x40
+#define FTDI_SIO_SET_DATA_PARITY_NONE (0x0 << 8)
+#define FTDI_SIO_SET_DATA_PARITY_ODD (0x1 << 8)
+#define FTDI_SIO_SET_DATA_PARITY_EVEN (0x2 << 8)
+#define FTDI_SIO_SET_DATA_PARITY_MARK (0x3 << 8)
+#define FTDI_SIO_SET_DATA_PARITY_SPACE (0x4 << 8)
+#define FTDI_SIO_SET_DATA_STOP_BITS_1 (0x0 << 11)
+#define FTDI_SIO_SET_DATA_STOP_BITS_15 (0x1 << 11)
+#define FTDI_SIO_SET_DATA_STOP_BITS_2 (0x2 << 11)
+#define FTDI_SIO_SET_BREAK (0x1 << 14)
+/* FTDI_SIO_SET_DATA */
+
+/*
+ * BmRequestType: 0100 0000B
+ * bRequest: FTDI_SIO_SET_DATA
+ * wValue: Data characteristics (see below)
+ * wIndex: Port
+ * wLength: 0
+ * Data: No
+ *
+ * Data characteristics
+ *
+ * B0..7 Number of data bits
+ * B8..10 Parity
+ * 0 = None
+ * 1 = Odd
+ * 2 = Even
+ * 3 = Mark
+ * 4 = Space
+ * B11..13 Stop Bits
+ * 0 = 1
+ * 1 = 1.5
+ * 2 = 2
+ * B14
+ * 1 = TX ON (break)
+ * 0 = TX OFF (normal state)
+ * B15 Reserved
+ *
+ */
+
+
+
+/* FTDI_SIO_MODEM_CTRL */
+#define FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE 0x40
+#define FTDI_SIO_SET_MODEM_CTRL_REQUEST FTDI_SIO_MODEM_CTRL
+
+/*
+ * BmRequestType: 0100 0000B
+ * bRequest: FTDI_SIO_MODEM_CTRL
+ * wValue: ControlValue (see below)
+ * wIndex: Port
+ * wLength: 0
+ * Data: None
+ *
+ * NOTE: If the device is in RTS/CTS flow control, the RTS set by this
+ * command will be IGNORED without an error being returned
+ * Also - you can not set DTR and RTS with one control message
+ */
+
+#define FTDI_SIO_SET_DTR_MASK 0x1
+#define FTDI_SIO_SET_DTR_HIGH ((FTDI_SIO_SET_DTR_MASK << 8) | 1)
+#define FTDI_SIO_SET_DTR_LOW ((FTDI_SIO_SET_DTR_MASK << 8) | 0)
+#define FTDI_SIO_SET_RTS_MASK 0x2
+#define FTDI_SIO_SET_RTS_HIGH ((FTDI_SIO_SET_RTS_MASK << 8) | 2)
+#define FTDI_SIO_SET_RTS_LOW ((FTDI_SIO_SET_RTS_MASK << 8) | 0)
+
+/*
+ * ControlValue
+ * B0 DTR state
+ * 0 = reset
+ * 1 = set
+ * B1 RTS state
+ * 0 = reset
+ * 1 = set
+ * B2..7 Reserved
+ * B8 DTR state enable
+ * 0 = ignore
+ * 1 = use DTR state
+ * B9 RTS state enable
+ * 0 = ignore
+ * 1 = use RTS state
+ * B10..15 Reserved
+ */
+
+/* FTDI_SIO_SET_FLOW_CTRL */
+#define FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE 0x40
+#define FTDI_SIO_SET_FLOW_CTRL_REQUEST FTDI_SIO_SET_FLOW_CTRL
+#define FTDI_SIO_DISABLE_FLOW_CTRL 0x0
+#define FTDI_SIO_RTS_CTS_HS (0x1 << 8)
+#define FTDI_SIO_DTR_DSR_HS (0x2 << 8)
+#define FTDI_SIO_XON_XOFF_HS (0x4 << 8)
+/*
+ * BmRequestType: 0100 0000b
+ * bRequest: FTDI_SIO_SET_FLOW_CTRL
+ * wValue: Xoff/Xon
+ * wIndex: Protocol/Port - hIndex is protocol / lIndex is port
+ * wLength: 0
+ * Data: None
+ *
+ * hIndex protocol is:
+ * B0 Output handshaking using RTS/CTS
+ * 0 = disabled
+ * 1 = enabled
+ * B1 Output handshaking using DTR/DSR
+ * 0 = disabled
+ * 1 = enabled
+ * B2 Xon/Xoff handshaking
+ * 0 = disabled
+ * 1 = enabled
+ *
+ * A value of zero in the hIndex field disables handshaking
+ *
+ * If Xon/Xoff handshaking is specified, the hValue field should contain the
+ * XOFF character and the lValue field contains the XON character.
+ */
+
+/*
+ * FTDI_SIO_GET_LATENCY_TIMER
+ *
+ * Set the timeout interval. The FTDI collects data from the
+ * device, transmitting it to the host when either A) 62 bytes are
+ * received, or B) the timeout interval has elapsed and the buffer
+ * contains at least 1 byte. Setting this value to a small number
+ * can dramatically improve performance for applications which send
+ * small packets, since the default value is 16ms.
+ */
+#define FTDI_SIO_GET_LATENCY_TIMER_REQUEST FTDI_SIO_GET_LATENCY_TIMER
+#define FTDI_SIO_GET_LATENCY_TIMER_REQUEST_TYPE 0xC0
+
+/*
+ * BmRequestType: 1100 0000b
+ * bRequest: FTDI_SIO_GET_LATENCY_TIMER
+ * wValue: 0
+ * wIndex: Port
+ * wLength: 0
+ * Data: latency (on return)
+ */
+
+/*
+ * FTDI_SIO_SET_LATENCY_TIMER
+ *
+ * Set the timeout interval. The FTDI collects data from the
+ * device, transmitting it to the host when either A) 62 bytes are
+ * received, or B) the timeout interval has elapsed and the buffer
+ * contains at least 1 byte. Setting this value to a small number
+ * can dramatically improve performance for applications which send
+ * small packets, since the default value is 16ms.
+ */
+#define FTDI_SIO_SET_LATENCY_TIMER_REQUEST FTDI_SIO_SET_LATENCY_TIMER
+#define FTDI_SIO_SET_LATENCY_TIMER_REQUEST_TYPE 0x40
+
+/*
+ * BmRequestType: 0100 0000b
+ * bRequest: FTDI_SIO_SET_LATENCY_TIMER
+ * wValue: Latency (milliseconds)
+ * wIndex: Port
+ * wLength: 0
+ * Data: None
+ *
+ * wValue:
+ * B0..7 Latency timer
+ * B8..15 0
+ *
+ */
+
+/*
+ * FTDI_SIO_SET_EVENT_CHAR
+ *
+ * Set the special event character for the specified communications port.
+ * If the device sees this character it will immediately return the
+ * data read so far - rather than wait 40ms or until 62 bytes are read
+ * which is what normally happens.
+ */
+
+
+#define FTDI_SIO_SET_EVENT_CHAR_REQUEST FTDI_SIO_SET_EVENT_CHAR
+#define FTDI_SIO_SET_EVENT_CHAR_REQUEST_TYPE 0x40
+
+
+/*
+ * BmRequestType: 0100 0000b
+ * bRequest: FTDI_SIO_SET_EVENT_CHAR
+ * wValue: EventChar
+ * wIndex: Port
+ * wLength: 0
+ * Data: None
+ *
+ * wValue:
+ * B0..7 Event Character
+ * B8 Event Character Processing
+ * 0 = disabled
+ * 1 = enabled
+ * B9..15 Reserved
+ *
+ */
+
+/* FTDI_SIO_SET_ERROR_CHAR */
+
+/*
+ * Set the parity error replacement character for the specified communications
+ * port
+ */
+
+/*
+ * BmRequestType: 0100 0000b
+ * bRequest: FTDI_SIO_SET_EVENT_CHAR
+ * wValue: Error Char
+ * wIndex: Port
+ * wLength: 0
+ * Data: None
+ *
+ *Error Char
+ * B0..7 Error Character
+ * B8 Error Character Processing
+ * 0 = disabled
+ * 1 = enabled
+ * B9..15 Reserved
+ *
+ */
+
+/* FTDI_SIO_GET_MODEM_STATUS */
+/* Retrieve the current value of the modem status register */
+
+#define FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE 0xc0
+#define FTDI_SIO_GET_MODEM_STATUS_REQUEST FTDI_SIO_GET_MODEM_STATUS
+#define FTDI_SIO_CTS_MASK 0x10
+#define FTDI_SIO_DSR_MASK 0x20
+#define FTDI_SIO_RI_MASK 0x40
+#define FTDI_SIO_RLSD_MASK 0x80
+/*
+ * BmRequestType: 1100 0000b
+ * bRequest: FTDI_SIO_GET_MODEM_STATUS
+ * wValue: zero
+ * wIndex: Port
+ * wLength: 1
+ * Data: Status
+ *
+ * One byte of data is returned
+ * B0..3 0
+ * B4 CTS
+ * 0 = inactive
+ * 1 = active
+ * B5 DSR
+ * 0 = inactive
+ * 1 = active
+ * B6 Ring Indicator (RI)
+ * 0 = inactive
+ * 1 = active
+ * B7 Receive Line Signal Detect (RLSD)
+ * 0 = inactive
+ * 1 = active
+ */
+
+/* FTDI_SIO_SET_BITMODE */
+#define FTDI_SIO_SET_BITMODE_REQUEST_TYPE 0x40
+#define FTDI_SIO_SET_BITMODE_REQUEST FTDI_SIO_SET_BITMODE
+
+/* Possible bitmodes for FTDI_SIO_SET_BITMODE_REQUEST */
+#define FTDI_SIO_BITMODE_RESET 0x00
+#define FTDI_SIO_BITMODE_CBUS 0x20
+
+/* FTDI_SIO_READ_PINS */
+#define FTDI_SIO_READ_PINS_REQUEST_TYPE 0xc0
+#define FTDI_SIO_READ_PINS_REQUEST FTDI_SIO_READ_PINS
+
+/*
+ * FTDI_SIO_READ_EEPROM
+ *
+ * EEPROM format found in FTDI AN_201, "FT-X MTP memory Configuration",
+ * http://www.ftdichip.com/Support/Documents/AppNotes/AN_201_FT-X%20MTP%20Memory%20Configuration.pdf
+ */
+#define FTDI_SIO_READ_EEPROM_REQUEST_TYPE 0xc0
+#define FTDI_SIO_READ_EEPROM_REQUEST FTDI_SIO_READ_EEPROM
+
+#define FTDI_FTX_CBUS_MUX_GPIO 0x8
+#define FTDI_FT232R_CBUS_MUX_GPIO 0xa
+
+
+/* Descriptors returned by the device
+ *
+ * Device Descriptor
+ *
+ * Offset Field Size Value Description
+ * 0 bLength 1 0x12 Size of descriptor in bytes
+ * 1 bDescriptorType 1 0x01 DEVICE Descriptor Type
+ * 2 bcdUSB 2 0x0110 USB Spec Release Number
+ * 4 bDeviceClass 1 0x00 Class Code
+ * 5 bDeviceSubClass 1 0x00 SubClass Code
+ * 6 bDeviceProtocol 1 0x00 Protocol Code
+ * 7 bMaxPacketSize0 1 0x08 Maximum packet size for endpoint 0
+ * 8 idVendor 2 0x0403 Vendor ID
+ * 10 idProduct 2 0x8372 Product ID (FTDI_SIO_PID)
+ * 12 bcdDevice 2 0x0001 Device release number
+ * 14 iManufacturer 1 0x01 Index of man. string desc
+ * 15 iProduct 1 0x02 Index of prod string desc
+ * 16 iSerialNumber 1 0x02 Index of serial nmr string desc
+ * 17 bNumConfigurations 1 0x01 Number of possible configurations
+ *
+ * Configuration Descriptor
+ *
+ * Offset Field Size Value
+ * 0 bLength 1 0x09 Size of descriptor in bytes
+ * 1 bDescriptorType 1 0x02 CONFIGURATION Descriptor Type
+ * 2 wTotalLength 2 0x0020 Total length of data
+ * 4 bNumInterfaces 1 0x01 Number of interfaces supported
+ * 5 bConfigurationValue 1 0x01 Argument for SetCOnfiguration() req
+ * 6 iConfiguration 1 0x02 Index of config string descriptor
+ * 7 bmAttributes 1 0x20 Config characteristics Remote Wakeup
+ * 8 MaxPower 1 0x1E Max power consumption
+ *
+ * Interface Descriptor
+ *
+ * Offset Field Size Value
+ * 0 bLength 1 0x09 Size of descriptor in bytes
+ * 1 bDescriptorType 1 0x04 INTERFACE Descriptor Type
+ * 2 bInterfaceNumber 1 0x00 Number of interface
+ * 3 bAlternateSetting 1 0x00 Value used to select alternate
+ * 4 bNumEndpoints 1 0x02 Number of endpoints
+ * 5 bInterfaceClass 1 0xFF Class Code
+ * 6 bInterfaceSubClass 1 0xFF Subclass Code
+ * 7 bInterfaceProtocol 1 0xFF Protocol Code
+ * 8 iInterface 1 0x02 Index of interface string description
+ *
+ * IN Endpoint Descriptor
+ *
+ * Offset Field Size Value
+ * 0 bLength 1 0x07 Size of descriptor in bytes
+ * 1 bDescriptorType 1 0x05 ENDPOINT descriptor type
+ * 2 bEndpointAddress 1 0x82 Address of endpoint
+ * 3 bmAttributes 1 0x02 Endpoint attributes - Bulk
+ * 4 bNumEndpoints 2 0x0040 maximum packet size
+ * 5 bInterval 1 0x00 Interval for polling endpoint
+ *
+ * OUT Endpoint Descriptor
+ *
+ * Offset Field Size Value
+ * 0 bLength 1 0x07 Size of descriptor in bytes
+ * 1 bDescriptorType 1 0x05 ENDPOINT descriptor type
+ * 2 bEndpointAddress 1 0x02 Address of endpoint
+ * 3 bmAttributes 1 0x02 Endpoint attributes - Bulk
+ * 4 bNumEndpoints 2 0x0040 maximum packet size
+ * 5 bInterval 1 0x00 Interval for polling endpoint
+ *
+ * DATA FORMAT
+ *
+ * IN Endpoint
+ *
+ * The device reserves the first two bytes of data on this endpoint to contain
+ * the current values of the modem and line status registers. In the absence of
+ * data, the device generates a message consisting of these two status bytes
+ * every 40 ms
+ *
+ * Byte 0: Modem Status
+ *
+ * Offset Description
+ * B0 Reserved - must be 1
+ * B1 Reserved - must be 0
+ * B2 Reserved - must be 0
+ * B3 Reserved - must be 0
+ * B4 Clear to Send (CTS)
+ * B5 Data Set Ready (DSR)
+ * B6 Ring Indicator (RI)
+ * B7 Receive Line Signal Detect (RLSD)
+ *
+ * Byte 1: Line Status
+ *
+ * Offset Description
+ * B0 Data Ready (DR)
+ * B1 Overrun Error (OE)
+ * B2 Parity Error (PE)
+ * B3 Framing Error (FE)
+ * B4 Break Interrupt (BI)
+ * B5 Transmitter Holding Register (THRE)
+ * B6 Transmitter Empty (TEMT)
+ * B7 Error in RCVR FIFO
+ *
+ */
+#define FTDI_RS0_CTS (1 << 4)
+#define FTDI_RS0_DSR (1 << 5)
+#define FTDI_RS0_RI (1 << 6)
+#define FTDI_RS0_RLSD (1 << 7)
+
+#define FTDI_RS_DR 1
+#define FTDI_RS_OE (1<<1)
+#define FTDI_RS_PE (1<<2)
+#define FTDI_RS_FE (1<<3)
+#define FTDI_RS_BI (1<<4)
+#define FTDI_RS_THRE (1<<5)
+#define FTDI_RS_TEMT (1<<6)
+#define FTDI_RS_FIFO (1<<7)
+
+/*
+ * OUT Endpoint
+ *
+ * This device reserves the first bytes of data on this endpoint contain the
+ * length and port identifier of the message. For the FTDI USB Serial converter
+ * the port identifier is always 1.
+ *
+ * Byte 0: Line Status
+ *
+ * Offset Description
+ * B0 Reserved - must be 1
+ * B1 Reserved - must be 0
+ * B2..7 Length of message - (not including Byte 0)
+ *
+ */