src/jtag/drivers/usb_blaster/ublast_access_ftdi.c

   1 /*
   2  *   Driver for USB-JTAG, Altera USB-Blaster and compatibles
   3  *
   4  *   Inspired from original code from Kolja Waschk's USB-JTAG project
   5  *   (http://www.ixo.de/info/usb_jtag/), and from openocd project.
   6  *
   7  *   Copyright (C) 2012 Robert Jarzmik robert.jarzmik@free.fr
   8  *   Copyright (C) 2011 Ali Lown ali@lown.me.uk
   9  *   Copyright (C) 2009 Catalin Patulea cat@vv.carleton.ca
  10  *   Copyright (C) 2006 Kolja Waschk usbjtag@ixo.de
  11  *
  12  *   This program is free software; you can redistribute it and/or modify
  13  *   it under the terms of the GNU General Public License as published by
  14  *   the Free Software Foundation; either version 2 of the License, or
  15  *   (at your option) any later version.
  16  *
  17  *   This program is distributed in the hope that it will be useful,
  18  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  *   GNU General Public License for more details.
  21  *
  22  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27 #include <jtag/interface.h>
  28 #include <jtag/commands.h>
  29
  30 #include "ublast_access.h"
  31 #include <ftdi.h>
  32
  33 static struct ftdi_context *ublast_getftdic(struct ublast_lowlevel *low)
  34 {
  35         return low->priv;
  36 }
  37
  38 static int ublast_ftdi_read(struct ublast_lowlevel *low, uint8_t *buf,
  39                             unsigned size, uint32_t *bytes_read)
  40 {
  41         int retval;
  42         int timeout = 100;
  43         struct ftdi_context *ftdic = ublast_getftdic(low);
  44
  45         *bytes_read = 0;
  46         while ((*bytes_read < size) && timeout--) {
  47                 retval = ftdi_read_data(ftdic, buf + *bytes_read,
  48                                 size - *bytes_read);
  49                 if (retval < 0) {
  50                         *bytes_read = 0;
  51                         LOG_ERROR("ftdi_read_data: %s",
  52                                         ftdi_get_error_string(ftdic));
  53                         return ERROR_JTAG_DEVICE_ERROR;
  54                 }
  55                 *bytes_read += retval;
  56         }
  57         return ERROR_OK;
  58 }
  59
  60 static int ublast_ftdi_write(struct ublast_lowlevel *low, uint8_t *buf, int size,
  61                              uint32_t *bytes_written)
  62 {
  63         int retval;
  64         struct ftdi_context *ftdic = ublast_getftdic(low);
  65
  66         retval = ftdi_write_data(ftdic, buf, size);
  67         if (retval < 0) {
  68                 *bytes_written = 0;
  69                 LOG_ERROR("ftdi_write_data: %s",
  70                           ftdi_get_error_string(ftdic));
  71                 return ERROR_JTAG_DEVICE_ERROR;
  72         }
  73         *bytes_written = retval;
  74         return ERROR_OK;
  75 }
  76
  77 static int ublast_ftdi_init(struct ublast_lowlevel *low)
  78 {
  79         uint8_t latency_timer;
  80         struct ftdi_context *ftdic = ublast_getftdic(low);
  81
  82         LOG_INFO("usb blaster interface using libftdi");
  83         if (ftdi_init(ftdic) < 0)
  84                 return ERROR_JTAG_INIT_FAILED;
  85
  86         /* context, vendor id, product id */
  87         if (ftdi_usb_open(ftdic, low->ublast_vid, low->ublast_pid) < 0) {
  88                 LOG_ERROR("unable to open ftdi device: %s", ftdic->error_str);
  89                 return ERROR_JTAG_INIT_FAILED;
  90         }
  91
  92         if (ftdi_usb_reset(ftdic) < 0) {
  93                 LOG_ERROR("unable to reset ftdi device");
  94                 return ERROR_JTAG_INIT_FAILED;
  95         }
  96
  97         if (ftdi_set_latency_timer(ftdic, 2) < 0) {
  98                 LOG_ERROR("unable to set latency timer");
  99                 return ERROR_JTAG_INIT_FAILED;
 100         }
 101
 102         if (ftdi_get_latency_timer(ftdic, &latency_timer) < 0) {
 103                 LOG_ERROR("unable to get latency timer");
 104                 return ERROR_JTAG_INIT_FAILED;
 105         }
 106         LOG_DEBUG("current latency timer: %u", latency_timer);
 107
 108         ftdi_disable_bitbang(ftdic);
 109         return ERROR_OK;
 110 }
 111
 112 static int ublast_ftdi_quit(struct ublast_lowlevel *low)
 113 {
 114         struct ftdi_context *ftdic = ublast_getftdic(low);
 115
 116         ftdi_usb_close(ftdic);
 117         ftdi_deinit(ftdic);
 118         return ERROR_OK;
 119 };
 120
 121 static struct ublast_lowlevel_priv {
 122         struct ftdi_context ftdic;
 123 } info;
 124
 125 static struct ublast_lowlevel low = {
 126         .open = ublast_ftdi_init,
 127         .close = ublast_ftdi_quit,
 128         .read = ublast_ftdi_read,
 129         .write = ublast_ftdi_write,
 130         .priv = &info,
 131 };
 132
 133 struct ublast_lowlevel *ublast_register_ftdi(void)
 134 {
 135         return &low;
 136 }