ft2232_spi.c - external/coreboot.org/flashrom - Git at Google

 /*
  * This file is part of the flashrom project.
  *
  * Copyright (C) 2009 Paul Fox <pgf@laptop.org>
  * Copyright (C) 2009, 2010 Carl-Daniel Hailfinger
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; version 2 of the License.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  */

 #if CONFIG_FT2232_SPI == 1

 #include <stdio.h>
 #include <strings.h>
 #include <string.h>
 #include <stdlib.h>
 #include <ctype.h>
 #include "flash.h"
 #include "programmer.h"
 #include "spi.h"
 #include <ftdi.h>

 /* This is not defined in libftdi.h <0.20 (c7e4c09e68cfa6f5e112334aa1b3bb23401c8dc7 to be exact).
  * Some tests indicate that his is the only change that it is needed to support the FT232H in flashrom. */
 #if !defined(HAVE_FT232H)
 #define TYPE_232H	6
 #endif

 /* Please keep sorted by vendor ID, then device ID. */

 #define FTDI_VID		0x0403
 #define FTDI_FT2232H_PID	0x6010
 #define FTDI_FT4232H_PID	0x6011
 #define FTDI_FT232H_PID		0x6014
 #define TIAO_TUMPA_PID		0x8a98
 #define TIAO_TUMPA_LITE_PID	0x8a99
 #define AMONTEC_JTAGKEY_PID	0xCFF8

 #define GOEPEL_VID		0x096C
 #define GOEPEL_PICOTAP_PID	0x1449

 #define FIC_VID			0x1457
 #define OPENMOKO_DBGBOARD_PID	0x5118

 #define OLIMEX_VID		0x15BA
 #define OLIMEX_ARM_OCD_PID	0x0003
 #define OLIMEX_ARM_TINY_PID	0x0004
 #define OLIMEX_ARM_OCD_H_PID	0x002B
 #define OLIMEX_ARM_TINY_H_PID	0x002A

 #define GOOGLE_VID		0x18D1
 #define GOOGLE_SERVO_PID	0x5001
 #define GOOGLE_SERVO_V2_PID0	0x5002
 #define GOOGLE_SERVO_V2_PID1	0x5003

 const struct dev_entry devs_ft2232spi[] = {
 	{FTDI_VID, FTDI_FT2232H_PID, OK, "FTDI", "FT2232H"},
 	{FTDI_VID, FTDI_FT4232H_PID, OK, "FTDI", "FT4232H"},
 	{FTDI_VID, FTDI_FT232H_PID, OK, "FTDI", "FT232H"},
 	{FTDI_VID, TIAO_TUMPA_PID, OK, "TIAO", "USB Multi-Protocol Adapter"},
 	{FTDI_VID, TIAO_TUMPA_LITE_PID, OK, "TIAO", "USB Multi-Protocol Adapter Lite"},
 	{FTDI_VID, AMONTEC_JTAGKEY_PID, OK, "Amontec", "JTAGkey"},
 	{GOEPEL_VID, GOEPEL_PICOTAP_PID, OK, "GOEPEL", "PicoTAP"},
 	{GOOGLE_VID, GOOGLE_SERVO_PID, OK, "Google", "Servo"},
 	{GOOGLE_VID, GOOGLE_SERVO_V2_PID0, OK, "Google", "Servo V2 Legacy"},
 	{GOOGLE_VID, GOOGLE_SERVO_V2_PID1, OK, "Google", "Servo V2"},
 	{FIC_VID, OPENMOKO_DBGBOARD_PID, OK, "FIC", "OpenMoko Neo1973 Debug board (V2+)"},
 	{OLIMEX_VID, OLIMEX_ARM_OCD_PID, OK, "Olimex", "ARM-USB-OCD"},
 	{OLIMEX_VID, OLIMEX_ARM_TINY_PID, OK, "Olimex", "ARM-USB-TINY"},
 	{OLIMEX_VID, OLIMEX_ARM_OCD_H_PID, OK, "Olimex", "ARM-USB-OCD-H"},
 	{OLIMEX_VID, OLIMEX_ARM_TINY_H_PID, OK, "Olimex", "ARM-USB-TINY-H"},

 	{0},
 };

 #define DEFAULT_DIVISOR 2

 #define BITMODE_BITBANG_NORMAL	1
 #define BITMODE_BITBANG_SPI	2

 /* The variables cs_bits and pindir store the values for the "set data bits low byte" MPSSE command that
  * sets the initial state and the direction of the I/O pins. The pin offsets are as follows:
  * SCK is bit 0.
  * DO  is bit 1.
  * DI  is bit 2.
  * CS  is bit 3.
  *
  * The default values (set below) are used for most devices:
  *  value: 0x08  CS=high, DI=low, DO=low, SK=low
  *    dir: 0x0b  CS=output, DI=input, DO=output, SK=output
  */
 static uint8_t cs_bits = 0x08;
 static uint8_t pindir = 0x0b;
 static struct ftdi_context ftdic_context;

 static const char *get_ft2232_devicename(int ft2232_vid, int ft2232_type)
 {
 	int i;
 	for (i = 0; devs_ft2232spi[i].vendor_name != NULL; i++) {
 		if ((devs_ft2232spi[i].device_id == ft2232_type) && (devs_ft2232spi[i].vendor_id == ft2232_vid))
 				return devs_ft2232spi[i].device_name;
 	}
 	return "unknown device";
 }

 static const char *get_ft2232_vendorname(int ft2232_vid, int ft2232_type)
 {
 	int i;
 	for (i = 0; devs_ft2232spi[i].vendor_name != NULL; i++) {
 		if ((devs_ft2232spi[i].device_id == ft2232_type) && (devs_ft2232spi[i].vendor_id == ft2232_vid))
 				return devs_ft2232spi[i].vendor_name;
 	}
 	return "unknown vendor";
 }

 static int send_buf(struct ftdi_context *ftdic, const unsigned char *buf,
 		    int size)
 {
 	int r;
 	r = ftdi_write_data(ftdic, (unsigned char *) buf, size);
 	if (r < 0) {
 		msg_perr("ftdi_write_data: %d, %s\n", r, ftdi_get_error_string(ftdic));
 		return 1;
 	}
 	return 0;
 }

 static int get_buf(struct ftdi_context *ftdic, const unsigned char *buf,
 		   int size)
 {
 	int r;

 	while (size > 0) {
 		r = ftdi_read_data(ftdic, (unsigned char *) buf, size);
 		if (r < 0) {
 			msg_perr("ftdi_read_data: %d, %s\n", r, ftdi_get_error_string(ftdic));
 			return 1;
 		}
 		buf += r;
 		size -= r;
 	}
 	return 0;
 }

 static int ft2232_spi_send_command(struct flashctx *flash,
 				   unsigned int writecnt, unsigned int readcnt,
 				   const unsigned char *writearr,
 				   unsigned char *readarr);

 static const struct spi_master spi_master_ft2232 = {
 	.type		= SPI_CONTROLLER_FT2232,
 	.features	= SPI_MASTER_4BA,
 	.max_data_read	= 64 * 1024,
 	.max_data_write	= 256,
 	.command	= ft2232_spi_send_command,
 	.multicommand	= default_spi_send_multicommand,
 	.read		= default_spi_read,
 	.write_256	= default_spi_write_256,
 	.write_aai	= default_spi_write_aai,
 };

 /* Returns 0 upon success, a negative number upon errors. */
 int ft2232_spi_init(void)
 {
 	int ret = 0;
 	struct ftdi_context *ftdic = &ftdic_context;
 	unsigned char buf[512];
 	int ft2232_vid = FTDI_VID;
 	int ft2232_type = FTDI_FT4232H_PID;
 	int channel_count = 4; /* Stores the number of channels of the device. */
 	enum ftdi_interface ft2232_interface = INTERFACE_A;
 	/*
 	 * The 'H' chips can run with an internal clock of either 12 MHz or 60 MHz,
 	 * but the non-H chips can only run at 12 MHz. We enable the divide-by-5
 	 * prescaler on the former to run on the same speed.
 	 */
 	uint8_t clock_5x = 1;
 	/* In addition to the prescaler mentioned above there is also another
 	 * configurable one on all versions of the chips. Its divisor div can be
 	 * set by a 16 bit value x according to the following formula:
 	 * div = (1 + x) * 2 <-> x = div / 2 - 1
 	 * Hence the expressible divisors are all even numbers between 2 and
 	 * 2^17 (=131072) resulting in SCK frequencies of 6 MHz down to about
 	 * 92 Hz for 12 MHz inputs.
 	 */
 	uint32_t divisor = DEFAULT_DIVISOR;
 	int f;
 	char *arg;
 	double mpsse_clk;

 	arg = extract_programmer_param("type");
 	if (arg) {
 		if (!strcasecmp(arg, "2232H")) {
 			ft2232_type = FTDI_FT2232H_PID;
 			channel_count = 2;
 		} else if (!strcasecmp(arg, "4232H")) {
 			ft2232_type = FTDI_FT4232H_PID;
 			channel_count = 4;
 		} else if (!strcasecmp(arg, "232H")) {
 			ft2232_type = FTDI_FT232H_PID;
 			channel_count = 1;
 		} else if (!strcasecmp(arg, "jtagkey")) {
 			ft2232_type = AMONTEC_JTAGKEY_PID;
 			channel_count = 2;
 			/* JTAGkey(2) needs to enable its output via Bit4 / GPIOL0
 			*  value: 0x18  OE=high, CS=high, DI=low, DO=low, SK=low
 			*    dir: 0x1b  OE=output, CS=output, DI=input, DO=output, SK=output */
 			cs_bits = 0x18;
 			pindir = 0x1b;
 		} else if (!strcasecmp(arg, "picotap")) {
 			ft2232_vid = GOEPEL_VID;
 			ft2232_type = GOEPEL_PICOTAP_PID;
 			channel_count = 2;
 		} else if (!strcasecmp(arg, "tumpa")) {
 			/* Interface A is SPI1, B is SPI2. */
 			ft2232_type = TIAO_TUMPA_PID;
 			channel_count = 2;
 		} else if (!strcasecmp(arg, "tumpalite")) {
 			/* Only one channel is used on lite edition */
 			ft2232_type = TIAO_TUMPA_LITE_PID;
 			channel_count = 1;
 		} else if (!strcasecmp(arg, "busblaster")) {
 			/* In its default configuration it is a jtagkey clone */
 			ft2232_type = FTDI_FT2232H_PID;
 			channel_count = 2;
 			cs_bits = 0x18;
 			pindir = 0x1b;
 		} else if (!strcasecmp(arg, "openmoko")) {
 			ft2232_vid = FIC_VID;
 			ft2232_type = OPENMOKO_DBGBOARD_PID;
 			channel_count = 2;
 		} else if (!strcasecmp(arg, "arm-usb-ocd")) {
 			ft2232_vid = OLIMEX_VID;
 			ft2232_type = OLIMEX_ARM_OCD_PID;
 			channel_count = 2;
 			/* arm-usb-ocd(-h) has an output buffer that needs to be enabled by pulling ADBUS4 low.
 			*  value: 0x08  #OE=low, CS=high, DI=low, DO=low, SK=low
 			*    dir: 0x1b  #OE=output, CS=output, DI=input, DO=output, SK=output */
 			cs_bits = 0x08;
 			pindir = 0x1b;
 		} else if (!strcasecmp(arg, "arm-usb-tiny")) {
 			ft2232_vid = OLIMEX_VID;
 			ft2232_type = OLIMEX_ARM_TINY_PID;
 			channel_count = 2;
 		} else if (!strcasecmp(arg, "arm-usb-ocd-h")) {
 			ft2232_vid = OLIMEX_VID;
 			ft2232_type = OLIMEX_ARM_OCD_H_PID;
 			channel_count = 2;
 			/* See arm-usb-ocd */
 			cs_bits = 0x08;
 			pindir = 0x1b;
 		} else if (!strcasecmp(arg, "arm-usb-tiny-h")) {
 			ft2232_vid = OLIMEX_VID;
 			ft2232_type = OLIMEX_ARM_TINY_H_PID;
 			channel_count = 2;
 		} else if (!strcasecmp(arg, "google-servo")) {
 			ft2232_vid = GOOGLE_VID;
 			ft2232_type = GOOGLE_SERVO_PID;
 		} else if (!strcasecmp(arg, "google-servo-v2")) {
 			ft2232_vid = GOOGLE_VID;
 			ft2232_type = GOOGLE_SERVO_V2_PID1;
 			/* Default divisor is too fast, and chip ID fails */
 			divisor = 6;
 		} else if (!strcasecmp(arg, "google-servo-v2-legacy")) {
 			ft2232_vid = GOOGLE_VID;
 			ft2232_type = GOOGLE_SERVO_V2_PID0;
 		} else {
 			msg_perr("Error: Invalid device type specified.\n");
 			free(arg);
 			return -1;
 		}
 	}
 	free(arg);

 	arg = extract_programmer_param("port");
 	if (arg) {
 		switch (toupper((unsigned char)*arg)) {
 		case 'A':
 			ft2232_interface = INTERFACE_A;
 			break;
 		case 'B':
 			ft2232_interface = INTERFACE_B;
 			if (channel_count < 2)
 				channel_count = -1;
 			break;
 		case 'C':
 			ft2232_interface = INTERFACE_C;
 			if (channel_count < 3)
 				channel_count = -1;
 			break;
 		case 'D':
 			ft2232_interface = INTERFACE_D;
 			if (channel_count < 4)
 				channel_count = -1;
 			break;
 		default:
 			channel_count = -1;
 			break;
 		}
 		if (channel_count < 0 || strlen(arg) != 1) {
 			msg_perr("Error: Invalid channel/port/interface specified: \"%s\".\n", arg);
 			free(arg);
 			return -2;
 		}
 	}
 	free(arg);

 	arg = extract_programmer_param("divisor");
 	if (arg && strlen(arg)) {
 		unsigned int temp = 0;
 		char *endptr;
 		temp = strtoul(arg, &endptr, 10);
 		if (*endptr || temp < 2 || temp > 131072 || temp & 0x1) {
 			msg_perr("Error: Invalid SPI frequency divisor specified: \"%s\".\n"
 				 "Valid are even values between 2 and 131072.\n", arg);
 			free(arg);
 			return -2;
 		} else {
 			divisor = (uint32_t)temp;
 		}
 	}
 	free(arg);

 	arg = extract_programmer_param("csgpiol");
 	if (arg) {
 		char *endptr;
 		unsigned int temp = strtoul(arg, &endptr, 10);
 		if (*endptr || endptr == arg || temp > 3) {
 			msg_perr("Error: Invalid GPIOL specified: \"%s\".\n"
 				 "Valid values are between 0 and 3.\n", arg);
 			free(arg);
 			return -2;
 		} else {
 			unsigned int pin = temp + 4;
 			cs_bits |= 1 << pin;
 			pindir |= 1 << pin;
 		}
 	}
 	free(arg);

 	msg_pdbg("Using device type %s %s ",
 		 get_ft2232_vendorname(ft2232_vid, ft2232_type),
 		 get_ft2232_devicename(ft2232_vid, ft2232_type));
 	msg_pdbg("channel %s.\n",
 		 (ft2232_interface == INTERFACE_A) ? "A" :
 		 (ft2232_interface == INTERFACE_B) ? "B" :
 		 (ft2232_interface == INTERFACE_C) ? "C" : "D");

 	if (ftdi_init(ftdic) < 0) {
 		msg_perr("ftdi_init failed.\n");
 		return -3;
 	}

 	if (ftdi_set_interface(ftdic, ft2232_interface) < 0) {
 		msg_perr("Unable to select channel (%s).\n", ftdi_get_error_string(ftdic));
 	}

 	arg = extract_programmer_param("serial");
 	f = ftdi_usb_open_desc(ftdic, ft2232_vid, ft2232_type, NULL, arg);
 	free(arg);

 	if (f < 0 && f != -5) {
 		msg_perr("Unable to open FTDI device: %d (%s).\n", f, ftdi_get_error_string(ftdic));
 		return -4;
 	}

 	if (ftdic->type != TYPE_2232H && ftdic->type != TYPE_4232H && ftdic->type != TYPE_232H) {
 		msg_pdbg("FTDI chip type %d is not high-speed.\n", ftdic->type);
 		clock_5x = 0;
 	}

 	if (ftdi_usb_reset(ftdic) < 0) {
 		msg_perr("Unable to reset FTDI device (%s).\n", ftdi_get_error_string(ftdic));
 	}

 	if (ftdi_set_latency_timer(ftdic, 2) < 0) {
 		msg_perr("Unable to set latency timer (%s).\n", ftdi_get_error_string(ftdic));
 	}

 	if (ftdi_write_data_set_chunksize(ftdic, 256)) {
 		msg_perr("Unable to set chunk size (%s).\n", ftdi_get_error_string(ftdic));
 	}

 	if (ftdi_set_bitmode(ftdic, 0x00, BITMODE_BITBANG_SPI) < 0) {
 		msg_perr("Unable to set bitmode to SPI (%s).\n", ftdi_get_error_string(ftdic));
 	}

 	if (clock_5x) {
 		msg_pdbg("Disable divide-by-5 front stage\n");
 		buf[0] = 0x8a; /* Disable divide-by-5. DIS_DIV_5 in newer libftdi */
 		if (send_buf(ftdic, buf, 1)) {
 			ret = -5;
 			goto ftdi_err;
 		}
 		mpsse_clk = 60.0;
 	} else {
 		mpsse_clk = 12.0;
 	}

 	msg_pdbg("Set clock divisor\n");
 	buf[0] = TCK_DIVISOR;
 	buf[1] = (divisor / 2 - 1) & 0xff;
 	buf[2] = ((divisor / 2 - 1) >> 8) & 0xff;
 	if (send_buf(ftdic, buf, 3)) {
 		ret = -6;
 		goto ftdi_err;
 	}

 	msg_pdbg("MPSSE clock: %f MHz, divisor: %u, SPI clock: %f MHz\n",
 		 mpsse_clk, divisor, (double)(mpsse_clk / divisor));

 	/* Disconnect TDI/DO to TDO/DI for loopback. */
 	msg_pdbg("No loopback of TDI/DO TDO/DI\n");
 	buf[0] = LOOPBACK_END;
 	if (send_buf(ftdic, buf, 1)) {
 		ret = -7;
 		goto ftdi_err;
 	}

 	msg_pdbg("Set data bits\n");
 	buf[0] = SET_BITS_LOW;
 	buf[1] = cs_bits;
 	buf[2] = pindir;
 	if (send_buf(ftdic, buf, 3)) {
 		ret = -8;
 		goto ftdi_err;
 	}

 	register_spi_master(&spi_master_ft2232);

 	return 0;

 ftdi_err:
 	if ((f = ftdi_usb_close(ftdic)) < 0) {
 		msg_perr("Unable to close FTDI device: %d (%s)\n", f, ftdi_get_error_string(ftdic));
 	}
 	return ret;
 }

 /* Returns 0 upon success, a negative number upon errors. */
 static int ft2232_spi_send_command(struct flashctx *flash,
 				   unsigned int writecnt, unsigned int readcnt,
 				   const unsigned char *writearr,
 				   unsigned char *readarr)
 {
 	struct ftdi_context *ftdic = &ftdic_context;
 	static unsigned char *buf = NULL;
 	/* failed is special. We use bitwise ops, but it is essentially bool. */
 	int i = 0, ret = 0, failed = 0;
 	int bufsize;
 	static int oldbufsize = 0;

 	if (writecnt > 65536 || readcnt > 65536)
 		return SPI_INVALID_LENGTH;

 	/* buf is not used for the response from the chip. */
 	bufsize = max(writecnt + 9, 260 + 9);
 	/* Never shrink. realloc() calls are expensive. */
 	if (bufsize > oldbufsize) {
 		buf = realloc(buf, bufsize);
 		if (!buf) {
 			msg_perr("Out of memory!\n");
 			/* TODO: What to do with buf? */
 			return SPI_GENERIC_ERROR;
 		}
 		oldbufsize = bufsize;
 	}

 	/*
 	 * Minimize USB transfers by packing as many commands as possible
 	 * together. If we're not expecting to read, we can assert CS#, write,
 	 * and deassert CS# all in one shot. If reading, we do three separate
 	 * operations.
 	 */
 	msg_pspew("Assert CS#\n");
 	buf[i++] = SET_BITS_LOW;
 	buf[i++] = 0 & ~cs_bits; /* assertive */
 	buf[i++] = pindir;

 	if (writecnt) {
 		buf[i++] = MPSSE_DO_WRITE | MPSSE_WRITE_NEG;
 		buf[i++] = (writecnt - 1) & 0xff;
 		buf[i++] = ((writecnt - 1) >> 8) & 0xff;
 		memcpy(buf + i, writearr, writecnt);
 		i += writecnt;
 	}

 	/*
 	 * Optionally terminate this batch of commands with a
 	 * read command, then do the fetch of the results.
 	 */
 	if (readcnt) {
 		buf[i++] = MPSSE_DO_READ;
 		buf[i++] = (readcnt - 1) & 0xff;
 		buf[i++] = ((readcnt - 1) >> 8) & 0xff;
 		ret = send_buf(ftdic, buf, i);
 		failed = ret;
 		/* We can't abort here, we still have to deassert CS#. */
 		if (ret)
 			msg_perr("send_buf failed before read: %i\n", ret);
 		i = 0;
 		if (ret == 0) {
 			/*
 			 * FIXME: This is unreliable. There's no guarantee that
 			 * we read the response directly after sending the read
 			 * command. We may be scheduled out etc.
 			 */
 			ret = get_buf(ftdic, readarr, readcnt);
 			failed |= ret;
 			/* We can't abort here either. */
 			if (ret)
 				msg_perr("get_buf failed: %i\n", ret);
 		}
 	}

 	msg_pspew("De-assert CS#\n");
 	buf[i++] = SET_BITS_LOW;
 	buf[i++] = cs_bits;
 	buf[i++] = pindir;
 	ret = send_buf(ftdic, buf, i);
 	failed |= ret;
 	if (ret)
 		msg_perr("send_buf failed at end: %i\n", ret);

 	return failed ? -1 : 0;
 }

 #endif
	/*
	* This file is part of the flashrom project.
	*
	* Copyright (C) 2009 Paul Fox <pgf@laptop.org>
	* Copyright (C) 2009, 2010 Carl-Daniel Hailfinger
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; version 2 of the License.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*/

	#if CONFIG_FT2232_SPI == 1

	#include <stdio.h>
	#include <strings.h>
	#include <string.h>
	#include <stdlib.h>
	#include <ctype.h>
	#include "flash.h"
	#include "programmer.h"
	#include "spi.h"
	#include <ftdi.h>

	/* This is not defined in libftdi.h <0.20 (c7e4c09e68cfa6f5e112334aa1b3bb23401c8dc7 to be exact).
	* Some tests indicate that his is the only change that it is needed to support the FT232H in flashrom. */
	#if !defined(HAVE_FT232H)
	#define TYPE_232H 6
	#endif

	/* Please keep sorted by vendor ID, then device ID. */

	#define FTDI_VID 0x0403
	#define FTDI_FT2232H_PID 0x6010
	#define FTDI_FT4232H_PID 0x6011
	#define FTDI_FT232H_PID 0x6014
	#define TIAO_TUMPA_PID 0x8a98
	#define TIAO_TUMPA_LITE_PID 0x8a99
	#define AMONTEC_JTAGKEY_PID 0xCFF8

	#define GOEPEL_VID 0x096C
	#define GOEPEL_PICOTAP_PID 0x1449

	#define FIC_VID 0x1457
	#define OPENMOKO_DBGBOARD_PID 0x5118

	#define OLIMEX_VID 0x15BA
	#define OLIMEX_ARM_OCD_PID 0x0003
	#define OLIMEX_ARM_TINY_PID 0x0004
	#define OLIMEX_ARM_OCD_H_PID 0x002B
	#define OLIMEX_ARM_TINY_H_PID 0x002A

	#define GOOGLE_VID 0x18D1
	#define GOOGLE_SERVO_PID 0x5001
	#define GOOGLE_SERVO_V2_PID0 0x5002
	#define GOOGLE_SERVO_V2_PID1 0x5003

	const struct dev_entry devs_ft2232spi[] = {
	{FTDI_VID, FTDI_FT2232H_PID, OK, "FTDI", "FT2232H"},
	{FTDI_VID, FTDI_FT4232H_PID, OK, "FTDI", "FT4232H"},
	{FTDI_VID, FTDI_FT232H_PID, OK, "FTDI", "FT232H"},
	{FTDI_VID, TIAO_TUMPA_PID, OK, "TIAO", "USB Multi-Protocol Adapter"},
	{FTDI_VID, TIAO_TUMPA_LITE_PID, OK, "TIAO", "USB Multi-Protocol Adapter Lite"},
	{FTDI_VID, AMONTEC_JTAGKEY_PID, OK, "Amontec", "JTAGkey"},
	{GOEPEL_VID, GOEPEL_PICOTAP_PID, OK, "GOEPEL", "PicoTAP"},
	{GOOGLE_VID, GOOGLE_SERVO_PID, OK, "Google", "Servo"},
	{GOOGLE_VID, GOOGLE_SERVO_V2_PID0, OK, "Google", "Servo V2 Legacy"},
	{GOOGLE_VID, GOOGLE_SERVO_V2_PID1, OK, "Google", "Servo V2"},
	{FIC_VID, OPENMOKO_DBGBOARD_PID, OK, "FIC", "OpenMoko Neo1973 Debug board (V2+)"},
	{OLIMEX_VID, OLIMEX_ARM_OCD_PID, OK, "Olimex", "ARM-USB-OCD"},
	{OLIMEX_VID, OLIMEX_ARM_TINY_PID, OK, "Olimex", "ARM-USB-TINY"},
	{OLIMEX_VID, OLIMEX_ARM_OCD_H_PID, OK, "Olimex", "ARM-USB-OCD-H"},
	{OLIMEX_VID, OLIMEX_ARM_TINY_H_PID, OK, "Olimex", "ARM-USB-TINY-H"},

	{0},
	};

	#define DEFAULT_DIVISOR 2

	#define BITMODE_BITBANG_NORMAL 1
	#define BITMODE_BITBANG_SPI 2

	/* The variables cs_bits and pindir store the values for the "set data bits low byte" MPSSE command that
	* sets the initial state and the direction of the I/O pins. The pin offsets are as follows:
	* SCK is bit 0.
	* DO is bit 1.
	* DI is bit 2.
	* CS is bit 3.
	*
	* The default values (set below) are used for most devices:
	* value: 0x08 CS=high, DI=low, DO=low, SK=low
	* dir: 0x0b CS=output, DI=input, DO=output, SK=output
	*/
	static uint8_t cs_bits = 0x08;
	static uint8_t pindir = 0x0b;
	static struct ftdi_context ftdic_context;

	static const char *get_ft2232_devicename(int ft2232_vid, int ft2232_type)
	{
	int i;
	for (i = 0; devs_ft2232spi[i].vendor_name != NULL; i++) {
	if ((devs_ft2232spi[i].device_id == ft2232_type) && (devs_ft2232spi[i].vendor_id == ft2232_vid))
	return devs_ft2232spi[i].device_name;
	}
	return "unknown device";
	}

	static const char *get_ft2232_vendorname(int ft2232_vid, int ft2232_type)
	{
	int i;
	for (i = 0; devs_ft2232spi[i].vendor_name != NULL; i++) {
	if ((devs_ft2232spi[i].device_id == ft2232_type) && (devs_ft2232spi[i].vendor_id == ft2232_vid))
	return devs_ft2232spi[i].vendor_name;
	}
	return "unknown vendor";
	}

	static int send_buf(struct ftdi_context ftdic, const unsigned char buf,
	int size)
	{
	int r;
	r = ftdi_write_data(ftdic, (unsigned char *) buf, size);
	if (r < 0) {
	msg_perr("ftdi_write_data: %d, %s\n", r, ftdi_get_error_string(ftdic));
	return 1;
	}
	return 0;
	}

	static int get_buf(struct ftdi_context ftdic, const unsigned char buf,
	int size)
	{
	int r;

	while (size > 0) {
	r = ftdi_read_data(ftdic, (unsigned char *) buf, size);
	if (r < 0) {
	msg_perr("ftdi_read_data: %d, %s\n", r, ftdi_get_error_string(ftdic));
	return 1;
	}
	buf += r;
	size -= r;
	}
	return 0;
	}

	static int ft2232_spi_send_command(struct flashctx *flash,
	unsigned int writecnt, unsigned int readcnt,
	const unsigned char *writearr,
	unsigned char *readarr);

	static const struct spi_master spi_master_ft2232 = {
	.type = SPI_CONTROLLER_FT2232,
	.features = SPI_MASTER_4BA,
	.max_data_read = 64 * 1024,
	.max_data_write = 256,
	.command = ft2232_spi_send_command,
	.multicommand = default_spi_send_multicommand,
	.read = default_spi_read,
	.write_256 = default_spi_write_256,
	.write_aai = default_spi_write_aai,
	};

	/* Returns 0 upon success, a negative number upon errors. */
	int ft2232_spi_init(void)
	{
	int ret = 0;
	struct ftdi_context *ftdic = &ftdic_context;
	unsigned char buf[512];
	int ft2232_vid = FTDI_VID;
	int ft2232_type = FTDI_FT4232H_PID;
	int channel_count = 4; /* Stores the number of channels of the device. */
	enum ftdi_interface ft2232_interface = INTERFACE_A;
	/*
	* The 'H' chips can run with an internal clock of either 12 MHz or 60 MHz,
	* but the non-H chips can only run at 12 MHz. We enable the divide-by-5
	* prescaler on the former to run on the same speed.
	*/
	uint8_t clock_5x = 1;
	/* In addition to the prescaler mentioned above there is also another
	* configurable one on all versions of the chips. Its divisor div can be
	* set by a 16 bit value x according to the following formula:
	* div = (1 + x) * 2 <-> x = div / 2 - 1
	* Hence the expressible divisors are all even numbers between 2 and
	* 2^17 (=131072) resulting in SCK frequencies of 6 MHz down to about
	* 92 Hz for 12 MHz inputs.
	*/
	uint32_t divisor = DEFAULT_DIVISOR;
	int f;
	char *arg;
	double mpsse_clk;

	arg = extract_programmer_param("type");
	if (arg) {
	if (!strcasecmp(arg, "2232H")) {
	ft2232_type = FTDI_FT2232H_PID;
	channel_count = 2;
	} else if (!strcasecmp(arg, "4232H")) {
	ft2232_type = FTDI_FT4232H_PID;
	channel_count = 4;
	} else if (!strcasecmp(arg, "232H")) {
	ft2232_type = FTDI_FT232H_PID;
	channel_count = 1;
	} else if (!strcasecmp(arg, "jtagkey")) {
	ft2232_type = AMONTEC_JTAGKEY_PID;
	channel_count = 2;
	/* JTAGkey(2) needs to enable its output via Bit4 / GPIOL0
	* value: 0x18 OE=high, CS=high, DI=low, DO=low, SK=low
	* dir: 0x1b OE=output, CS=output, DI=input, DO=output, SK=output */
	cs_bits = 0x18;
	pindir = 0x1b;
	} else if (!strcasecmp(arg, "picotap")) {
	ft2232_vid = GOEPEL_VID;
	ft2232_type = GOEPEL_PICOTAP_PID;
	channel_count = 2;
	} else if (!strcasecmp(arg, "tumpa")) {
	/* Interface A is SPI1, B is SPI2. */
	ft2232_type = TIAO_TUMPA_PID;
	channel_count = 2;
	} else if (!strcasecmp(arg, "tumpalite")) {
	/* Only one channel is used on lite edition */
	ft2232_type = TIAO_TUMPA_LITE_PID;
	channel_count = 1;
	} else if (!strcasecmp(arg, "busblaster")) {
	/* In its default configuration it is a jtagkey clone */
	ft2232_type = FTDI_FT2232H_PID;
	channel_count = 2;
	cs_bits = 0x18;
	pindir = 0x1b;
	} else if (!strcasecmp(arg, "openmoko")) {
	ft2232_vid = FIC_VID;
	ft2232_type = OPENMOKO_DBGBOARD_PID;
	channel_count = 2;
	} else if (!strcasecmp(arg, "arm-usb-ocd")) {
	ft2232_vid = OLIMEX_VID;
	ft2232_type = OLIMEX_ARM_OCD_PID;
	channel_count = 2;
	/* arm-usb-ocd(-h) has an output buffer that needs to be enabled by pulling ADBUS4 low.
	* value: 0x08 #OE=low, CS=high, DI=low, DO=low, SK=low
	* dir: 0x1b #OE=output, CS=output, DI=input, DO=output, SK=output */
	cs_bits = 0x08;
	pindir = 0x1b;
	} else if (!strcasecmp(arg, "arm-usb-tiny")) {
	ft2232_vid = OLIMEX_VID;
	ft2232_type = OLIMEX_ARM_TINY_PID;
	channel_count = 2;
	} else if (!strcasecmp(arg, "arm-usb-ocd-h")) {
	ft2232_vid = OLIMEX_VID;
	ft2232_type = OLIMEX_ARM_OCD_H_PID;
	channel_count = 2;
	/* See arm-usb-ocd */
	cs_bits = 0x08;
	pindir = 0x1b;
	} else if (!strcasecmp(arg, "arm-usb-tiny-h")) {
	ft2232_vid = OLIMEX_VID;
	ft2232_type = OLIMEX_ARM_TINY_H_PID;
	channel_count = 2;
	} else if (!strcasecmp(arg, "google-servo")) {
	ft2232_vid = GOOGLE_VID;
	ft2232_type = GOOGLE_SERVO_PID;
	} else if (!strcasecmp(arg, "google-servo-v2")) {
	ft2232_vid = GOOGLE_VID;
	ft2232_type = GOOGLE_SERVO_V2_PID1;
	/* Default divisor is too fast, and chip ID fails */
	divisor = 6;
	} else if (!strcasecmp(arg, "google-servo-v2-legacy")) {
	ft2232_vid = GOOGLE_VID;
	ft2232_type = GOOGLE_SERVO_V2_PID0;
	} else {
	msg_perr("Error: Invalid device type specified.\n");
	free(arg);
	return -1;
	}
	}
	free(arg);

	arg = extract_programmer_param("port");
	if (arg) {
	switch (toupper((unsigned char)*arg)) {
	case 'A':
	ft2232_interface = INTERFACE_A;
	break;
	case 'B':
	ft2232_interface = INTERFACE_B;
	if (channel_count < 2)
	channel_count = -1;
	break;
	case 'C':
	ft2232_interface = INTERFACE_C;
	if (channel_count < 3)
	channel_count = -1;
	break;
	case 'D':
	ft2232_interface = INTERFACE_D;
	if (channel_count < 4)
	channel_count = -1;
	break;
	default:
	channel_count = -1;
	break;
	}
	if (channel_count < 0 \|\| strlen(arg) != 1) {
	msg_perr("Error: Invalid channel/port/interface specified: \"%s\".\n", arg);
	free(arg);
	return -2;
	}
	}
	free(arg);

	arg = extract_programmer_param("divisor");
	if (arg && strlen(arg)) {
	unsigned int temp = 0;
	char *endptr;
	temp = strtoul(arg, &endptr, 10);
	if (*endptr \|\| temp < 2 \|\| temp > 131072 \|\| temp & 0x1) {
	msg_perr("Error: Invalid SPI frequency divisor specified: \"%s\".\n"
	"Valid are even values between 2 and 131072.\n", arg);
	free(arg);
	return -2;
	} else {
	divisor = (uint32_t)temp;
	}
	}
	free(arg);

	arg = extract_programmer_param("csgpiol");
	if (arg) {
	char *endptr;
	unsigned int temp = strtoul(arg, &endptr, 10);
	if (*endptr \|\| endptr == arg \|\| temp > 3) {
	msg_perr("Error: Invalid GPIOL specified: \"%s\".\n"
	"Valid values are between 0 and 3.\n", arg);
	free(arg);
	return -2;
	} else {
	unsigned int pin = temp + 4;
	cs_bits \|= 1 << pin;
	pindir \|= 1 << pin;
	}
	}
	free(arg);

	msg_pdbg("Using device type %s %s ",
	get_ft2232_vendorname(ft2232_vid, ft2232_type),
	get_ft2232_devicename(ft2232_vid, ft2232_type));
	msg_pdbg("channel %s.\n",
	(ft2232_interface == INTERFACE_A) ? "A" :
	(ft2232_interface == INTERFACE_B) ? "B" :
	(ft2232_interface == INTERFACE_C) ? "C" : "D");

	if (ftdi_init(ftdic) < 0) {
	msg_perr("ftdi_init failed.\n");
	return -3;
	}

	if (ftdi_set_interface(ftdic, ft2232_interface) < 0) {
	msg_perr("Unable to select channel (%s).\n", ftdi_get_error_string(ftdic));
	}

	arg = extract_programmer_param("serial");
	f = ftdi_usb_open_desc(ftdic, ft2232_vid, ft2232_type, NULL, arg);
	free(arg);

	if (f < 0 && f != -5) {
	msg_perr("Unable to open FTDI device: %d (%s).\n", f, ftdi_get_error_string(ftdic));
	return -4;
	}

	if (ftdic->type != TYPE_2232H && ftdic->type != TYPE_4232H && ftdic->type != TYPE_232H) {
	msg_pdbg("FTDI chip type %d is not high-speed.\n", ftdic->type);
	clock_5x = 0;
	}

	if (ftdi_usb_reset(ftdic) < 0) {
	msg_perr("Unable to reset FTDI device (%s).\n", ftdi_get_error_string(ftdic));
	}

	if (ftdi_set_latency_timer(ftdic, 2) < 0) {
	msg_perr("Unable to set latency timer (%s).\n", ftdi_get_error_string(ftdic));
	}

	if (ftdi_write_data_set_chunksize(ftdic, 256)) {
	msg_perr("Unable to set chunk size (%s).\n", ftdi_get_error_string(ftdic));
	}

	if (ftdi_set_bitmode(ftdic, 0x00, BITMODE_BITBANG_SPI) < 0) {
	msg_perr("Unable to set bitmode to SPI (%s).\n", ftdi_get_error_string(ftdic));
	}

	if (clock_5x) {
	msg_pdbg("Disable divide-by-5 front stage\n");
	buf[0] = 0x8a; /* Disable divide-by-5. DIS_DIV_5 in newer libftdi */
	if (send_buf(ftdic, buf, 1)) {
	ret = -5;
	goto ftdi_err;
	}
	mpsse_clk = 60.0;
	} else {
	mpsse_clk = 12.0;
	}

	msg_pdbg("Set clock divisor\n");
	buf[0] = TCK_DIVISOR;
	buf[1] = (divisor / 2 - 1) & 0xff;
	buf[2] = ((divisor / 2 - 1) >> 8) & 0xff;
	if (send_buf(ftdic, buf, 3)) {
	ret = -6;
	goto ftdi_err;
	}

	msg_pdbg("MPSSE clock: %f MHz, divisor: %u, SPI clock: %f MHz\n",
	mpsse_clk, divisor, (double)(mpsse_clk / divisor));

	/* Disconnect TDI/DO to TDO/DI for loopback. */
	msg_pdbg("No loopback of TDI/DO TDO/DI\n");
	buf[0] = LOOPBACK_END;
	if (send_buf(ftdic, buf, 1)) {
	ret = -7;
	goto ftdi_err;
	}

	msg_pdbg("Set data bits\n");
	buf[0] = SET_BITS_LOW;
	buf[1] = cs_bits;
	buf[2] = pindir;
	if (send_buf(ftdic, buf, 3)) {
	ret = -8;
	goto ftdi_err;
	}

	register_spi_master(&spi_master_ft2232);

	return 0;

	ftdi_err:
	if ((f = ftdi_usb_close(ftdic)) < 0) {
	msg_perr("Unable to close FTDI device: %d (%s)\n", f, ftdi_get_error_string(ftdic));
	}
	return ret;
	}

	/* Returns 0 upon success, a negative number upon errors. */
	static int ft2232_spi_send_command(struct flashctx *flash,
	unsigned int writecnt, unsigned int readcnt,
	const unsigned char *writearr,
	unsigned char *readarr)
	{
	struct ftdi_context *ftdic = &ftdic_context;
	static unsigned char *buf = NULL;
	/* failed is special. We use bitwise ops, but it is essentially bool. */
	int i = 0, ret = 0, failed = 0;
	int bufsize;
	static int oldbufsize = 0;

	if (writecnt > 65536 \|\| readcnt > 65536)
	return SPI_INVALID_LENGTH;

	/* buf is not used for the response from the chip. */
	bufsize = max(writecnt + 9, 260 + 9);
	/* Never shrink. realloc() calls are expensive. */
	if (bufsize > oldbufsize) {
	buf = realloc(buf, bufsize);
	if (!buf) {
	msg_perr("Out of memory!\n");
	/* TODO: What to do with buf? */
	return SPI_GENERIC_ERROR;
	}
	oldbufsize = bufsize;
	}

	/*
	* Minimize USB transfers by packing as many commands as possible
	* together. If we're not expecting to read, we can assert CS#, write,
	* and deassert CS# all in one shot. If reading, we do three separate
	* operations.
	*/
	msg_pspew("Assert CS#\n");
	buf[i++] = SET_BITS_LOW;
	buf[i++] = 0 & ~cs_bits; /* assertive */
	buf[i++] = pindir;

	if (writecnt) {
	buf[i++] = MPSSE_DO_WRITE \| MPSSE_WRITE_NEG;
	buf[i++] = (writecnt - 1) & 0xff;
	buf[i++] = ((writecnt - 1) >> 8) & 0xff;
	memcpy(buf + i, writearr, writecnt);
	i += writecnt;
	}

	/*
	* Optionally terminate this batch of commands with a
	* read command, then do the fetch of the results.
	*/
	if (readcnt) {
	buf[i++] = MPSSE_DO_READ;
	buf[i++] = (readcnt - 1) & 0xff;
	buf[i++] = ((readcnt - 1) >> 8) & 0xff;
	ret = send_buf(ftdic, buf, i);
	failed = ret;
	/* We can't abort here, we still have to deassert CS#. */
	if (ret)
	msg_perr("send_buf failed before read: %i\n", ret);
	i = 0;
	if (ret == 0) {
	/*
	* FIXME: This is unreliable. There's no guarantee that
	* we read the response directly after sending the read
	* command. We may be scheduled out etc.
	*/
	ret = get_buf(ftdic, readarr, readcnt);
	failed \|= ret;
	/* We can't abort here either. */
	if (ret)
	msg_perr("get_buf failed: %i\n", ret);
	}
	}

	msg_pspew("De-assert CS#\n");
	buf[i++] = SET_BITS_LOW;
	buf[i++] = cs_bits;
	buf[i++] = pindir;
	ret = send_buf(ftdic, buf, i);
	failed \|= ret;
	if (ret)
	msg_perr("send_buf failed at end: %i\n", ret);

	return failed ? -1 : 0;
	}

	#endif