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- /* 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 */
- /* Interface indices for FT2232, FT2232H and FT4232H devices */
- #define INTERFACE_A 1
- #define INTERFACE_B 2
- #define INTERFACE_C 3
- #define INTERFACE_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_chip_type {
- SIO = 1,
- FT8U232AM = 2,
- FT232BM = 3,
- FT2232C = 4,
- FT232RL = 5,
- FT2232H = 6,
- FT4232H = 7,
- FT232H = 8,
- FTX = 9,
- };
- 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 slave
- * 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 slave
- * 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)
- *
- */
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