- remove target specific variant and use target->variant member

[openocd.git] / src / jtag / presto.c

/***************************************************************************
 *   Copyright (C) 2007 by Pavel Chromy                                    *
 *   chromy@asix.cz                                                        *
 *                                                                         *
 *   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; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   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.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#if IS_CYGWIN == 1
#include "windows.h"
#endif

#include "replacements.h"

/* project specific includes */
#include "log.h"
#include "types.h"
#include "jtag.h"
#include "configuration.h"
#include "time_support.h"
#include "bitq.h"

/* system includes */
#include <string.h>
#include <stdlib.h>
#include <unistd.h>

/* PRESTO access library includes */
#if BUILD_PRESTO_FTD2XX == 1
#include <ftd2xx.h>
#elif BUILD_PRESTO_LIBFTDI == 1
#include <ftdi.h>
#else
#error "BUG: either FTD2XX and LIBFTDI has to be used"
#endif

int presto_jtag_speed(int speed);
int presto_jtag_khz(int khz, int *jtag_speed);
int presto_jtag_speed_div(int speed, int *khz);
int presto_jtag_register_commands(struct command_context_s *cmd_ctx);
int presto_jtag_init(void);
int presto_jtag_quit(void);

jtag_interface_t presto_interface =
{
        .name = "presto",
        .execute_queue = bitq_execute_queue,
        .speed = presto_jtag_speed,
        .khz = presto_jtag_khz,
        .speed_div = presto_jtag_speed_div,
        .register_commands = presto_jtag_register_commands,
        .init = presto_jtag_init,
        .quit = presto_jtag_quit,
};

int presto_bitq_out(int tms, int tdi, int tdo_req);
int presto_bitq_flush(void);
int presto_bitq_sleep(unsigned long us);
int presto_bitq_reset(int trst, int srst);
int presto_bitq_in_rdy(void);
int presto_bitq_in(void);

bitq_interface_t presto_bitq =
{
        .out = presto_bitq_out,
        .flush = presto_bitq_flush,
        .sleep = presto_bitq_sleep,
        .reset = presto_bitq_reset,
        .in_rdy = presto_bitq_in_rdy,
        .in = presto_bitq_in,
};

/* -------------------------------------------------------------------------- */

#define FT_DEVICE_NAME_LEN 64
#define FT_DEVICE_SERNUM_LEN 64

#define PRESTO_VID_PID 0x0403f1a0
#define PRESTO_VID (0x0403)
#define PRESTO_PID (0xf1a0)

#define BUFFER_SIZE (64*62)

typedef struct presto_s
{
#if BUILD_PRESTO_FTD2XX == 1
        FT_HANDLE handle;
        FT_STATUS status;
#elif BUILD_PRESTO_LIBFTDI == 1
        struct ftdi_context ftdic;
        int retval;
#endif

        char serial[FT_DEVICE_SERNUM_LEN];

        u8 buff_out[BUFFER_SIZE];
        int buff_out_pos;

        u8 buff_in[BUFFER_SIZE];
        int buff_in_exp; /* expected in buffer length */
        int buff_in_len; /* length of data received */
        int buff_in_pos;

        unsigned long total_out;
        unsigned long total_in;

        int jtag_tms; /* last tms state */
        int jtag_tck; /* last tck state */
        int jtag_rst; /* last trst state */

        int jtag_tdi_data;
        int jtag_tdi_count;

        int jtag_speed;
        
} presto_t;

presto_t presto_state;
presto_t *presto = &presto_state;

u8 presto_init_seq[] =
{
        0x80, 0xA0, 0xA8, 0xB0, 0xC0, 0xE0
};

int presto_write(u8 *buf, int size)
{
#if BUILD_PRESTO_FTD2XX == 1
        DWORD ftbytes;
        if ((presto->status = FT_Write(presto->handle, buf, size, &ftbytes)) != FT_OK)
        {
                LOG_ERROR("FT_Write returned: %lu", presto->status);
                return ERROR_JTAG_DEVICE_ERROR;
        }

#elif BUILD_PRESTO_LIBFTDI == 1
        u32 ftbytes;
        if ((presto->retval = ftdi_write_data(&presto->ftdic, buf, size)) < 0)
        {
                LOG_ERROR("ftdi_write_data: %s", ftdi_get_error_string(&presto->ftdic));
                return ERROR_JTAG_DEVICE_ERROR;
        }
        ftbytes = presto->retval;
#endif

        if (ftbytes != size)
        {
                LOG_ERROR("couldn't write the requested number of bytes to PRESTO (%i < %i)", ftbytes, size);
                return ERROR_JTAG_DEVICE_ERROR;
        }

        return ERROR_OK;
}

int presto_read(u8* buf, int size)
{
#if BUILD_PRESTO_FTD2XX == 1
        DWORD ftbytes;
        if ((presto->status = FT_Read(presto->handle, buf, size, &ftbytes)) != FT_OK)
        {
                LOG_ERROR("FT_Read returned: %lu", presto->status);
                return ERROR_JTAG_DEVICE_ERROR;
        }

#elif BUILD_PRESTO_LIBFTDI == 1
        u32 ftbytes = 0;

        struct timeval timeout, now;
        gettimeofday(&timeout, NULL);
        timeval_add_time(&timeout, 1, 0); /* one second timeout */

        while (ftbytes < size)
        {
                if ((presto->retval = ftdi_read_data(&presto->ftdic, buf + ftbytes, size - ftbytes)) < 0)
                {
                        LOG_ERROR("ftdi_read_data: %s", ftdi_get_error_string(&presto->ftdic));
                        return ERROR_JTAG_DEVICE_ERROR;
                }
                ftbytes += presto->retval;

                gettimeofday(&now, NULL);
                if ((now.tv_sec > timeout.tv_sec) || ((now.tv_sec == timeout.tv_sec) && (now.tv_usec > timeout.tv_usec)))
                        break;
        }
#endif

        if (ftbytes != size)
        {
                /* this is just a warning, there might have been timeout when detecting PRESTO, which is not fatal */
                LOG_WARNING("couldn't read the requested number of bytes from PRESTO (%i < %i)", ftbytes, size);
                return ERROR_JTAG_DEVICE_ERROR;
        }

        return ERROR_OK;
}

#if BUILD_PRESTO_FTD2XX == 1
int presto_open_ftd2xx(char *req_serial)
{
        int i;
        DWORD numdevs;
        DWORD vidpid;
        char devname[FT_DEVICE_NAME_LEN];
        FT_DEVICE device;

        BYTE presto_data;
        DWORD ftbytes;

        presto->handle = (FT_HANDLE)INVALID_HANDLE_VALUE;

#if IS_WIN32 == 0
        /* Add non-standard Vid/Pid to the linux driver */
        if ((presto->status = FT_SetVIDPID(PRESTO_VID, PRESTO_PID)) != FT_OK)
        {
                LOG_ERROR("couldn't add PRESTO VID/PID");
                exit(-1);
        }
#endif

        if ((presto->status = FT_ListDevices(&numdevs, NULL, FT_LIST_NUMBER_ONLY)) != FT_OK)
        {
                LOG_ERROR("FT_ListDevices failed: %i", (int)presto->status);
                return ERROR_JTAG_DEVICE_ERROR;
        }

        LOG_DEBUG("FTDI devices available: %i", numdevs);
        for (i = 0; i < numdevs; i++)
        {
                if ((presto->status = FT_Open(i, &(presto->handle))) != FT_OK)
                {
                        /* this is not fatal, the device may be legitimately open by other process, hence debug message only */
                        LOG_DEBUG("FT_Open failed: %i", (int)presto->status);
                        continue;
                }
                LOG_DEBUG("FTDI device %i open", i);

                if ((presto->status = FT_GetDeviceInfo(presto->handle, &device, &vidpid,
                                presto->serial, devname, NULL)) == FT_OK)
                {
                        if (vidpid == PRESTO_VID_PID
                                        && (req_serial == NULL || !strcmp(presto->serial, req_serial)))
                                break;
                }
                else
                        LOG_DEBUG("FT_GetDeviceInfo failed: %i", presto->status);

                LOG_DEBUG("FTDI device %i does not match, closing", i);
                FT_Close(presto->handle);
                presto->handle = (FT_HANDLE)INVALID_HANDLE_VALUE;
        }

        if (presto->handle == (FT_HANDLE)INVALID_HANDLE_VALUE)
                return ERROR_JTAG_DEVICE_ERROR; /* presto not open, return */

        if ((presto->status = FT_SetLatencyTimer(presto->handle, 1)) != FT_OK)
                return ERROR_JTAG_DEVICE_ERROR;


        if ((presto->status = FT_SetTimeouts(presto->handle, 100, 0)) != FT_OK)
                return ERROR_JTAG_DEVICE_ERROR;

        if ((presto->status = FT_Purge(presto->handle, FT_PURGE_TX | FT_PURGE_RX)) != FT_OK)
                return ERROR_JTAG_DEVICE_ERROR;

        presto_data = 0xD0;
        if ((presto->status = FT_Write(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
                return ERROR_JTAG_DEVICE_ERROR;

        /* delay between first write/read turnaround (after purge?) necessary under Linux for unknown reason,
           probably a bug in library threading */
        usleep(100000);
        if ((presto->status = FT_Read(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
                return ERROR_JTAG_DEVICE_ERROR;

        if (ftbytes!=1)
        {
                LOG_DEBUG("PRESTO reset");

                if ((presto->status = FT_Purge(presto->handle, FT_PURGE_TX | FT_PURGE_RX)) != FT_OK)
                        return ERROR_JTAG_DEVICE_ERROR;
                if ((presto->status = FT_SetBitMode(presto->handle, 0x80, 1)) != FT_OK)
                        return ERROR_JTAG_DEVICE_ERROR;
                if ((presto->status = FT_SetBaudRate(presto->handle, 9600)) != FT_OK)
                        return ERROR_JTAG_DEVICE_ERROR;

                presto_data = 0;
                for (i = 0; i < 4 * 62; i++)
                        if ((presto->status=FT_Write(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
                                return ERROR_JTAG_DEVICE_ERROR;

                usleep(100000);

                if ((presto->status = FT_SetBitMode(presto->handle, 0x00, 0)) != FT_OK)
                        return ERROR_JTAG_DEVICE_ERROR;

                if ((presto->status = FT_Purge(presto->handle, FT_PURGE_TX | FT_PURGE_RX)) != FT_OK)
                        return ERROR_JTAG_DEVICE_ERROR;

                presto_data = 0xD0;
                if ((presto->status = FT_Write(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
                        return ERROR_JTAG_DEVICE_ERROR;

                /* delay between first write/read turnaround (after purge?) necessary under Linux for unknown reason,
                   probably a bug in library threading */
                usleep(100000);
                if ((presto->status = FT_Read(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
                        return ERROR_JTAG_DEVICE_ERROR;

                if (ftbytes!=1)
                {
                        LOG_DEBUG("PRESTO not responding");
                        return ERROR_JTAG_DEVICE_ERROR;
                }
        }

        if ((presto->status = FT_SetTimeouts(presto->handle, 0, 0)) != FT_OK)
                return ERROR_JTAG_DEVICE_ERROR;


        presto->status = FT_Write(presto->handle, &presto_init_seq, sizeof(presto_init_seq), &ftbytes);
        if (presto->status != FT_OK || ftbytes != sizeof(presto_init_seq))
                return ERROR_JTAG_DEVICE_ERROR;

        return ERROR_OK;
}

#elif BUILD_PRESTO_LIBFTDI == 1
int presto_open_libftdi(char *req_serial)
{
        u8 presto_data;

        LOG_DEBUG("searching for PRESTO using libftdi");

        /* initialize FTDI context structure */
        if (ftdi_init(&presto->ftdic) < 0)
        {
                LOG_ERROR("unable to init libftdi: %s", presto->ftdic.error_str);
                return ERROR_JTAG_DEVICE_ERROR;
        }

        /* context, vendor id, product id */
        if (ftdi_usb_open_desc(&presto->ftdic, PRESTO_VID, PRESTO_PID, NULL, req_serial) < 0)
        {
                LOG_ERROR("unable to open PRESTO: %s", presto->ftdic.error_str);
                return ERROR_JTAG_DEVICE_ERROR;
        }

        if (ftdi_usb_reset(&presto->ftdic) < 0)
        {
                LOG_ERROR("unable to reset PRESTO device");
                return ERROR_JTAG_DEVICE_ERROR;
        }

        if (ftdi_set_latency_timer(&presto->ftdic, 1) < 0)
        {
                LOG_ERROR("unable to set latency timer");
                return ERROR_JTAG_DEVICE_ERROR;
        }

        if (ftdi_usb_purge_buffers(&presto->ftdic) < 0)
        {
                LOG_ERROR("unable to purge PRESTO buffers");
                return ERROR_JTAG_DEVICE_ERROR;
        }

        presto_data = 0xD0;
        if (presto_write(&presto_data, 1) != ERROR_OK)
        {
                LOG_ERROR("error writing to PRESTO");
                return ERROR_JTAG_DEVICE_ERROR;
        }

        if (presto_read(&presto_data, 1) != ERROR_OK)
        {
                LOG_DEBUG("no response from PRESTO, retrying");

                if (ftdi_usb_purge_buffers(&presto->ftdic) < 0)
                        return ERROR_JTAG_DEVICE_ERROR;

                presto_data = 0xD0;
                if (presto_write(&presto_data, 1) != ERROR_OK)
                        return ERROR_JTAG_DEVICE_ERROR;

                if (presto_read(&presto_data, 1) != ERROR_OK)
                {
                        LOG_ERROR("no response from PRESTO, giving up");
                        return ERROR_JTAG_DEVICE_ERROR;
                }
        }

        if (presto_write(presto_init_seq, sizeof(presto_init_seq)) != ERROR_OK)
        {
                LOG_ERROR("error writing PRESTO init sequence");
                return ERROR_JTAG_DEVICE_ERROR;
        }

        return ERROR_OK;
}
#endif /* BUILD_PRESTO_LIBFTDI == 1 */

int presto_open(char *req_serial)
{
        presto->buff_out_pos=0;
        presto->buff_in_pos=0;
        presto->buff_in_len=0;
        presto->buff_in_exp=0;

        presto->total_out=0;
        presto->total_in=0;

        presto->jtag_tms=0;
        presto->jtag_tck=0;
        presto->jtag_rst=0;
        presto->jtag_tdi_data=0;
        presto->jtag_tdi_count=0;

        presto->jtag_speed=0;
        
#if BUILD_PRESTO_FTD2XX == 1
        return presto_open_ftd2xx(req_serial);
#elif BUILD_PRESTO_LIBFTDI == 1
        return presto_open_libftdi(req_serial);
#endif
}

int presto_close(void)
{

        int result = ERROR_OK;

#if BUILD_PRESTO_FTD2XX == 1
        unsigned long ftbytes;

        if (presto->handle == (FT_HANDLE)INVALID_HANDLE_VALUE)
                return result;

        presto->status = FT_Purge(presto->handle, FT_PURGE_TX | FT_PURGE_RX);
        if (presto->status != FT_OK)
                result = ERROR_JTAG_DEVICE_ERROR;

        presto->status = FT_Write(presto->handle, &presto_init_seq, sizeof(presto_init_seq), &ftbytes);
        if (presto->status != FT_OK || ftbytes != sizeof(presto_init_seq))
                result = ERROR_JTAG_DEVICE_ERROR;

        if ((presto->status = FT_SetLatencyTimer(presto->handle, 16)) != FT_OK)
                result = ERROR_JTAG_DEVICE_ERROR;

        if ((presto->status = FT_Close(presto->handle)) != FT_OK)
                result = ERROR_JTAG_DEVICE_ERROR;
        else
                presto->handle = (FT_HANDLE)INVALID_HANDLE_VALUE;

#elif BUILD_PRESTO_LIBFTDI == 1

        if ((presto->retval = ftdi_write_data(&presto->ftdic, presto_init_seq, sizeof(presto_init_seq))) != sizeof(presto_init_seq))
                result = ERROR_JTAG_DEVICE_ERROR;

        if ((presto->retval = ftdi_set_latency_timer(&presto->ftdic, 16)) < 0)
                result = ERROR_JTAG_DEVICE_ERROR;

        if ((presto->retval = ftdi_usb_close(&presto->ftdic)) < 0)
                result = ERROR_JTAG_DEVICE_ERROR;
        else
                ftdi_deinit(&presto->ftdic);
#endif

        return result;
}

int presto_flush(void)
{
        if (presto->buff_out_pos == 0)
                return ERROR_OK;

#if BUILD_PRESTO_FTD2XX == 1
        if (presto->status != FT_OK)
#elif BUILD_PRESTO_LIBFTDI == 1
        if (presto->retval < 0)
#endif
        {
                LOG_DEBUG("error in previous communication, canceling I/O operation");
                return ERROR_JTAG_DEVICE_ERROR;
        }

        if (presto_write(presto->buff_out, presto->buff_out_pos) != ERROR_OK)
        {
                presto->buff_out_pos = 0;
                return ERROR_JTAG_DEVICE_ERROR;
        }

        presto->total_out += presto->buff_out_pos;
        presto->buff_out_pos = 0;

        if (presto->buff_in_exp == 0)
                return ERROR_OK;

        presto->buff_in_pos = 0;
        presto->buff_in_len = 0;

        if (presto_read(presto->buff_in, presto->buff_in_exp) != ERROR_OK)
        {
                presto->buff_in_exp = 0;
                return ERROR_JTAG_DEVICE_ERROR;
        }

        presto->total_in += presto->buff_in_exp;
        presto->buff_in_len = presto->buff_in_exp;
        presto->buff_in_exp = 0;

        return ERROR_OK;
}

int presto_sendbyte(int data)
{
        if (data == EOF) return presto_flush();

        if (presto->buff_out_pos < BUFFER_SIZE)
        {
                presto->buff_out[presto->buff_out_pos++] = (u8)data;
                if (((data & 0xC0) == 0x40) || ((data & 0xD0)== 0xD0))
                        presto->buff_in_exp++;
        }
        else
                return ERROR_JTAG_DEVICE_ERROR;

#if BUILD_PRESTO_FTD2XX == 1
        if (presto->buff_out_pos >= BUFFER_SIZE)
#elif BUILD_PRESTO_LIBFTDI == 1
        /* libftdi does not do background read, be sure that USB IN buffer does not overflow (128 bytes only!) */
        if (presto->buff_out_pos >= BUFFER_SIZE || presto->buff_in_exp==128)
#endif
                return presto_flush();

        return ERROR_OK;
}

int presto_getbyte(void)
{
        if (presto->buff_in_pos < presto->buff_in_len)
                return presto->buff_in[presto->buff_in_pos++];

        if (presto->buff_in_exp == 0)
                return -1;

        if (presto_flush() != ERROR_OK)
                return -1;

        if (presto->buff_in_pos<presto->buff_in_len)
                return presto->buff_in[presto->buff_in_pos++];

        return -1;
}

/* -------------------------------------------------------------------------- */

int presto_tdi_flush(void)
{
        if (presto->jtag_tdi_count == 0)
                return 0;

        if (presto->jtag_tck == 0)
        {
                LOG_ERROR("BUG: unexpected TAP condition, TCK low");
                return -1;
        }

        presto->jtag_tdi_data |= (presto->jtag_tdi_count - 1) << 4;
        presto_sendbyte(presto->jtag_tdi_data);
        presto->jtag_tdi_count = 0;
        presto->jtag_tdi_data = 0;
        
        return 0;
}

int presto_tck_idle(void)
{
        if (presto->jtag_tck == 1)
        {
                presto_sendbyte(0xCA);
                presto->jtag_tck = 0;
        }
        
        return 0;
}

/* -------------------------------------------------------------------------- */

int presto_bitq_out(int tms, int tdi, int tdo_req)
{
        int i;
        unsigned char cmd;

        if (presto->jtag_tck == 0)
        {
                presto_sendbyte(0xA4); /* LED idicator - JTAG active */
        }
        else if (presto->jtag_speed == 0 && !tdo_req && tms == presto->jtag_tms)
        {
                presto->jtag_tdi_data |= (tdi != 0) << presto->jtag_tdi_count;

                if (++presto->jtag_tdi_count == 4)
                        presto_tdi_flush();

                return 0;
        }

        presto_tdi_flush();

        cmd = tdi ? 0xCB : 0xCA;
        presto_sendbyte(cmd);

        if (tms != presto->jtag_tms)
        {
                presto_sendbyte((tms ? 0xEC : 0xE8) | (presto->jtag_rst ? 0x02 : 0));
                presto->jtag_tms = tms;
        }

        /* delay with TCK low */
        for (i=presto->jtag_speed; i>1; i--)
                presto_sendbyte(cmd);

        cmd |= 0x04;
        presto_sendbyte(cmd | (tdo_req ? 0x10 : 0));

        /* delay with TCK high */
        for (i=presto->jtag_speed; i>1; i--)
                presto_sendbyte(cmd);

        presto->jtag_tck = 1;

        return 0;
}

int presto_bitq_flush(void)
{
        presto_tdi_flush();
        presto_tck_idle();

        presto_sendbyte(0xA0); /* LED idicator - JTAG idle */

        return presto_flush();
}

int presto_bitq_in_rdy(void)
{
        if (presto->buff_in_pos>=presto->buff_in_len)
                return 0;
        return presto->buff_in_len-presto->buff_in_pos;
}

int presto_bitq_in(void)
{
        if (presto->buff_in_pos>=presto->buff_in_len)
                return -1;
        if (presto->buff_in[presto->buff_in_pos++]&0x08) return 1;
        return 0;
}

int presto_bitq_sleep(unsigned long us)
{
        long waits;

        presto_tdi_flush();
        presto_tck_idle();

        if (us > 100000)
        {
                presto_bitq_flush();
                jtag_sleep(us);
                return 0;
        }

        waits = us / 170 + 2;
        while (waits--)
                presto_sendbyte(0x80);

        return 0;
}

int presto_bitq_reset(int trst, int srst)
{
        presto_tdi_flush();
        presto_tck_idle();

        /* add a delay after possible TCK transition */
        presto_sendbyte(0x80);
        presto_sendbyte(0x80);

        presto->jtag_rst = trst || srst;
        presto_sendbyte((presto->jtag_rst ? 0xEA : 0xE8) | (presto->jtag_tms ? 0x04 : 0));

        return 0;
}

/* -------------------------------------------------------------------------- */

int presto_jtag_khz(int khz, int *jtag_speed)
{
        if (khz < 0)
        {
                *jtag_speed=0;
                return ERROR_INVALID_ARGUMENTS;
        }

        if (khz >= 3000) *jtag_speed = 0;
        else *jtag_speed = (1000+khz-1)/khz;
        
        return 0;
}

int presto_jtag_speed_div(int speed, int *khz)
{
        if ((speed < 0) || (speed > 1000))
        {
                *khz=0;
                return ERROR_INVALID_ARGUMENTS;
        }

        if (speed == 0) *khz = 3000;
        else *khz = 1000/speed;
        
        return 0;
}

int presto_jtag_speed(int speed)
{
        int khz;
        
        if (presto_jtag_speed_div(speed, &khz))
        {
                return ERROR_INVALID_ARGUMENTS;
        }

        presto->jtag_speed = speed;
        
        if (khz%1000 == 0)
                LOG_INFO("setting speed to %d, max. TCK freq. is %d MHz", speed, khz/1000);
        else
                LOG_INFO("setting speed to %d, max. TCK freq. is %d kHz", speed, khz);
        
        return 0;
}

char *presto_serial;

int presto_handle_serial_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        if (argc == 1)
        {
                if (presto_serial)
                        free(presto_serial);
                presto_serial = strdup(args[0]);
        }
        else
        {
                LOG_ERROR("expected exactly one argument to presto_serial <serial-number>");
        }

        return ERROR_OK;
}

int presto_jtag_register_commands(struct command_context_s *cmd_ctx)
{
        register_command(cmd_ctx, NULL, "presto_serial", presto_handle_serial_command,
                COMMAND_CONFIG, NULL);
        return ERROR_OK;
}

int presto_jtag_init(void)
{
        if (presto_open(presto_serial) != ERROR_OK)
        {
                presto_close();
                if (presto_serial != NULL)
                        LOG_ERROR("Cannot open PRESTO, serial number '%s'", presto_serial);
                else
                        LOG_ERROR("Cannot open PRESTO");
                return ERROR_JTAG_INIT_FAILED;
        }
        LOG_INFO("PRESTO open, serial number '%s'", presto->serial);

        /* use JTAG speed setting from configuration file */
        presto_jtag_speed(jtag_speed);

        bitq_interface = &presto_bitq;
        return ERROR_OK;
}

int presto_jtag_quit(void)
{
        bitq_cleanup();
        presto_close();
        LOG_INFO("PRESTO closed");

        if (presto_serial)
        {
                free(presto_serial);
                presto_serial = NULL;
        }

        return ERROR_OK;
}