jtag: linuxgpiod: drop extra parenthesis

[openocd.git] / src / jtag / drivers / kitprog.c

// SPDX-License-Identifier: GPL-2.0-or-later

/***************************************************************************
 *   Copyright (C) 2007 by Juergen Stuber <juergen@jstuber.net>            *
 *   based on Dominic Rath's and Benedikt Sauter's usbprog.c               *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   Copyright (C) 2011 by Jean-Christophe PLAGNIOL-VIILARD                *
 *   plagnioj@jcrosoft.com                                                 *
 *                                                                         *
 *   Copyright (C) 2015 by Marc Schink                                     *
 *   openocd-dev@marcschink.de                                             *
 *                                                                         *
 *   Copyright (C) 2015 by Paul Fertser                                    *
 *   fercerpav@gmail.com                                                   *
 *                                                                         *
 *   Copyright (C) 2015-2017 by Forest Crossman                            *
 *   cyrozap@gmail.com                                                     *
 ***************************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdint.h>

#include <hidapi.h>

#include <jtag/interface.h>
#include <jtag/swd.h>
#include <jtag/commands.h>

#include "libusb_helper.h"

#define VID 0x04b4
#define PID 0xf139

#define BULK_EP_IN  1
#define BULK_EP_OUT 2

#define CONTROL_TYPE_READ  0x01
#define CONTROL_TYPE_WRITE 0x02

#define CONTROL_COMMAND_PROGRAM 0x07

#define CONTROL_MODE_POLL_PROGRAMMER_STATUS  0x01
#define CONTROL_MODE_RESET_TARGET            0x04
#define CONTROL_MODE_SET_PROGRAMMER_PROTOCOL 0x40
#define CONTROL_MODE_SYNCHRONIZE_TRANSFER    0x41
#define CONTROL_MODE_ACQUIRE_SWD_TARGET      0x42
#define CONTROL_MODE_SEND_SWD_SEQUENCE       0x43

#define PROTOCOL_JTAG 0x00
#define PROTOCOL_SWD  0x01

#define DEVICE_PSOC4   0x00
#define DEVICE_PSOC3   0x01
#define DEVICE_UNKNOWN 0x02
#define DEVICE_PSOC5   0x03

#define ACQUIRE_MODE_RESET       0x00
#define ACQUIRE_MODE_POWER_CYCLE 0x01

#define SEQUENCE_LINE_RESET  0x00
#define SEQUENCE_JTAG_TO_SWD 0x01

#define PROGRAMMER_NOK_NACK 0x00
#define PROGRAMMER_OK_ACK   0x01

#define HID_TYPE_WRITE 0x00
#define HID_TYPE_READ  0x01
#define HID_TYPE_START 0x02

#define HID_COMMAND_POWER      0x80
#define HID_COMMAND_VERSION    0x81
#define HID_COMMAND_RESET      0x82
#define HID_COMMAND_CONFIGURE  0x8f
#define HID_COMMAND_BOOTLOADER 0xa0

/* 512 bytes seemed to work reliably.
 * It works with both full queue of mostly reads or mostly writes.
 *
 * Unfortunately the commit 88f429ead019fd6df96ec15f0d897385f3cef0d0
 * 5321: target/cortex_m: faster reading of all CPU registers
 * revealed a serious Kitprog firmware problem:
 * If the queue contains more than 63 transactions in the repeated pattern
 * one write, two reads, the firmware fails badly.
 * Sending 64 transactions makes the adapter to loose the connection with the
 * device. Sending 65 or more transactions causes the adapter to stop
 * receiving USB HID commands, next kitprog_hid_command() stops in hid_write().
 *
 * The problem was detected with KitProg v2.12 and v2.16.
 * We can guess the problem is something like a buffer or stack overflow.
 *
 * Use shorter buffer as a workaround. 300 bytes (= 60 transactions) works.
 */
#define SWD_MAX_BUFFER_LENGTH 300

struct kitprog {
        hid_device *hid_handle;
        struct libusb_device_handle *usb_handle;
        uint16_t packet_size;
        uint16_t packet_index;
        uint8_t *packet_buffer;
        char *serial;
        uint8_t hardware_version;
        uint8_t minor_version;
        uint8_t major_version;
        uint16_t millivolts;

        bool supports_jtag_to_swd;
};

struct pending_transfer_result {
        uint8_t cmd;
        uint32_t data;
        void *buffer;
};

static bool kitprog_init_acquire_psoc;

static int pending_transfer_count, pending_queue_len;
static struct pending_transfer_result *pending_transfers;

static int queued_retval;

static struct kitprog *kitprog_handle;

static int kitprog_usb_open(void);
static void kitprog_usb_close(void);

static int kitprog_hid_command(uint8_t *command, size_t command_length,
                uint8_t *data, size_t data_length);
static int kitprog_get_version(void);
static int kitprog_get_millivolts(void);
static int kitprog_get_info(void);
static int kitprog_set_protocol(uint8_t protocol);
static int kitprog_get_status(void);
static int kitprog_set_unknown(void);
static int kitprog_acquire_psoc(uint8_t psoc_type, uint8_t acquire_mode,
                uint8_t max_attempts);
static int kitprog_reset_target(void);
static int kitprog_swd_sync(void);
static int kitprog_swd_seq(uint8_t seq_type);

static int kitprog_generic_acquire(void);

static int kitprog_swd_run_queue(void);
static void kitprog_swd_queue_cmd(uint8_t cmd, uint32_t *dst, uint32_t data);
static int kitprog_swd_switch_seq(enum swd_special_seq seq);


static inline int mm_to_version(uint8_t major, uint8_t minor)
{
        return (major << 8) | minor;
}

static int kitprog_init(void)
{
        int retval;

        kitprog_handle = malloc(sizeof(struct kitprog));
        if (!kitprog_handle) {
                LOG_ERROR("Failed to allocate memory");
                return ERROR_FAIL;
        }

        if (kitprog_usb_open() != ERROR_OK) {
                LOG_ERROR("Can't find a KitProg device! Please check device connections and permissions.");
                return ERROR_JTAG_INIT_FAILED;
        }

        /* Get the current KitProg version and target voltage */
        if (kitprog_get_info() != ERROR_OK)
                return ERROR_FAIL;

        /* Compatibility check */
        kitprog_handle->supports_jtag_to_swd = true;
        int kitprog_version = mm_to_version(kitprog_handle->major_version, kitprog_handle->minor_version);
        if (kitprog_version < mm_to_version(2, 14)) {
                LOG_WARNING("KitProg firmware versions below v2.14 do not support sending JTAG to SWD sequences. These sequences will be substituted with SWD line resets.");
                kitprog_handle->supports_jtag_to_swd = false;
        }

        /* I have no idea what this does */
        if (kitprog_set_unknown() != ERROR_OK)
                return ERROR_FAIL;

        /* SWD won't work unless we do this */
        if (kitprog_swd_sync() != ERROR_OK)
                return ERROR_FAIL;

        /* Set the protocol to SWD */
        if (kitprog_set_protocol(PROTOCOL_SWD) != ERROR_OK)
                return ERROR_FAIL;

        /* Reset the SWD bus */
        if (kitprog_swd_seq(SEQUENCE_LINE_RESET) != ERROR_OK)
                return ERROR_FAIL;

        if (kitprog_init_acquire_psoc) {
                /* Try to acquire any device that will respond */
                retval = kitprog_generic_acquire();
                if (retval != ERROR_OK) {
                        LOG_ERROR("No PSoC devices found");
                        return retval;
                }
        }

        /* Allocate packet buffers and queues */
        kitprog_handle->packet_size = SWD_MAX_BUFFER_LENGTH;
        kitprog_handle->packet_buffer = malloc(SWD_MAX_BUFFER_LENGTH);
        if (!kitprog_handle->packet_buffer) {
                LOG_ERROR("Failed to allocate memory for the packet buffer");
                return ERROR_FAIL;
        }

        pending_queue_len = SWD_MAX_BUFFER_LENGTH / 5;
        pending_transfers = malloc(pending_queue_len * sizeof(*pending_transfers));
        if (!pending_transfers) {
                LOG_ERROR("Failed to allocate memory for the SWD transfer queue");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_quit(void)
{
        kitprog_usb_close();

        free(kitprog_handle->packet_buffer);
        free(kitprog_handle->serial);
        free(kitprog_handle);
        free(pending_transfers);

        return ERROR_OK;
}

/*************** kitprog usb functions *********************/

static int kitprog_get_usb_serial(void)
{
        int retval;
        const uint8_t str_index = 128; /* This seems to be a constant */
        char desc_string[256+1]; /* Max size of string descriptor */

        retval = libusb_get_string_descriptor_ascii(kitprog_handle->usb_handle,
                        str_index, (unsigned char *)desc_string, sizeof(desc_string)-1);
        if (retval < 0) {
                LOG_ERROR("libusb_get_string_descriptor_ascii() failed with %d", retval);
                return ERROR_FAIL;
        }

        /* Null terminate descriptor string */
        desc_string[retval] = '\0';

        /* Allocate memory for the serial number */
        kitprog_handle->serial = calloc(retval + 1, sizeof(char));
        if (!kitprog_handle->serial) {
                LOG_ERROR("Failed to allocate memory for the serial number");
                return ERROR_FAIL;
        }

        /* Store the serial number */
        strncpy(kitprog_handle->serial, desc_string, retval + 1);

        return ERROR_OK;
}

static int kitprog_usb_open(void)
{
        const uint16_t vids[] = { VID, 0 };
        const uint16_t pids[] = { PID, 0 };

        if (jtag_libusb_open(vids, pids, NULL, &kitprog_handle->usb_handle, NULL) != ERROR_OK) {
                LOG_ERROR("Failed to open or find the device");
                return ERROR_FAIL;
        }

        /* Get the serial number for the device */
        if (kitprog_get_usb_serial() != ERROR_OK)
                LOG_WARNING("Failed to get KitProg serial number");

        /* Convert the ASCII serial number into a (wchar_t *) */
        size_t len = strlen(kitprog_handle->serial);
        wchar_t *hid_serial = calloc(len + 1, sizeof(wchar_t));
        if (!hid_serial) {
                LOG_ERROR("Failed to allocate memory for the serial number");
                return ERROR_FAIL;
        }
        if (mbstowcs(hid_serial, kitprog_handle->serial, len + 1) == (size_t)-1) {
                free(hid_serial);
                LOG_ERROR("Failed to convert serial number");
                return ERROR_FAIL;
        }

        /* Use HID for the KitBridge interface */
        kitprog_handle->hid_handle = hid_open(VID, PID, hid_serial);
        free(hid_serial);
        if (!kitprog_handle->hid_handle) {
                LOG_ERROR("Failed to open KitBridge (HID) interface");
                return ERROR_FAIL;
        }

        /* Claim the KitProg Programmer (bulk transfer) interface */
        if (libusb_claim_interface(kitprog_handle->usb_handle, 1) != ERROR_OK) {
                LOG_ERROR("Failed to claim KitProg Programmer (bulk transfer) interface");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static void kitprog_usb_close(void)
{
        if (kitprog_handle->hid_handle) {
                hid_close(kitprog_handle->hid_handle);
                hid_exit();
        }

        jtag_libusb_close(kitprog_handle->usb_handle);
}

/*************** kitprog lowlevel functions *********************/

static int kitprog_hid_command(uint8_t *command, size_t command_length,
                uint8_t *data, size_t data_length)
{
        int ret;

        ret = hid_write(kitprog_handle->hid_handle, command, command_length);
        if (ret < 0) {
                LOG_DEBUG("HID write returned %i", ret);
                return ERROR_FAIL;
        }

        ret = hid_read_timeout(kitprog_handle->hid_handle,
                                                        data, data_length, LIBUSB_TIMEOUT_MS);
        if (ret == 0) {
                LOG_ERROR("HID read timed out");
                return ERROR_TIMEOUT_REACHED;
        } else if (ret < 0) {
                LOG_ERROR("HID read error %ls", hid_error(kitprog_handle->hid_handle));
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_get_version(void)
{
        int ret;

        unsigned char command[3] = {HID_TYPE_START | HID_TYPE_WRITE, 0x00, HID_COMMAND_VERSION};
        unsigned char data[64];

        ret = kitprog_hid_command(command, sizeof(command), data, sizeof(data));
        if (ret != ERROR_OK)
                return ret;

        kitprog_handle->hardware_version = data[1];
        kitprog_handle->minor_version = data[2];
        kitprog_handle->major_version = data[3];

        return ERROR_OK;
}

static int kitprog_get_millivolts(void)
{
        int ret;

        unsigned char command[3] = {HID_TYPE_START | HID_TYPE_READ, 0x00, HID_COMMAND_POWER};
        unsigned char data[64];

        ret = kitprog_hid_command(command, sizeof(command), data, sizeof(data));
        if (ret != ERROR_OK)
                return ret;

        kitprog_handle->millivolts = (data[4] << 8) | data[3];

        return ERROR_OK;
}

static int kitprog_get_info(void)
{
        /* Get the device version information */
        if (kitprog_get_version() == ERROR_OK) {
                LOG_INFO("KitProg v%u.%02u",
                        kitprog_handle->major_version, kitprog_handle->minor_version);
                LOG_INFO("Hardware version: %u",
                        kitprog_handle->hardware_version);
        } else {
                LOG_ERROR("Failed to get KitProg version");
                return ERROR_FAIL;
        }

        /* Get the current reported target voltage */
        if (kitprog_get_millivolts() == ERROR_OK) {
                LOG_INFO("VTARG = %u.%03u V",
                        kitprog_handle->millivolts / 1000, kitprog_handle->millivolts % 1000);
        } else {
                LOG_ERROR("Failed to get target voltage");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_set_protocol(uint8_t protocol)
{
        int transferred;
        char status = PROGRAMMER_NOK_NACK;

        int retval = jtag_libusb_control_transfer(kitprog_handle->usb_handle,
                LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE,
                CONTROL_TYPE_WRITE,
                (CONTROL_MODE_SET_PROGRAMMER_PROTOCOL << 8) | CONTROL_COMMAND_PROGRAM,
                protocol, &status, 1, 0, &transferred);

        if (retval != ERROR_OK || transferred == 0) {
                LOG_DEBUG("Zero bytes transferred");
                return ERROR_FAIL;
        }

        if (status != PROGRAMMER_OK_ACK) {
                LOG_DEBUG("Programmer did not respond OK");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_get_status(void)
{
        int transferred = 0;
        char status = PROGRAMMER_NOK_NACK;

        /* Try a maximum of three times */
        for (int i = 0; (i < 3) && (transferred == 0); i++) {
                jtag_libusb_control_transfer(kitprog_handle->usb_handle,
                        LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE,
                        CONTROL_TYPE_READ,
                        (CONTROL_MODE_POLL_PROGRAMMER_STATUS << 8) | CONTROL_COMMAND_PROGRAM,
                        0, &status, 1, 0, &transferred);
                jtag_sleep(1000);
        }

        if (transferred == 0) {
                LOG_DEBUG("Zero bytes transferred");
                return ERROR_FAIL;
        }

        if (status != PROGRAMMER_OK_ACK) {
                LOG_DEBUG("Programmer did not respond OK");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_set_unknown(void)
{
        int transferred;
        char status = PROGRAMMER_NOK_NACK;

        int retval = jtag_libusb_control_transfer(kitprog_handle->usb_handle,
                LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE,
                CONTROL_TYPE_WRITE,
                (0x03 << 8) | 0x04,
                0, &status, 1, 0, &transferred);

        if (retval != ERROR_OK || transferred == 0) {
                LOG_DEBUG("Zero bytes transferred");
                return ERROR_FAIL;
        }

        if (status != PROGRAMMER_OK_ACK) {
                LOG_DEBUG("Programmer did not respond OK");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_acquire_psoc(uint8_t psoc_type, uint8_t acquire_mode,
                uint8_t max_attempts)
{
        int transferred;
        char status = PROGRAMMER_NOK_NACK;

        int retval = jtag_libusb_control_transfer(kitprog_handle->usb_handle,
                LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE,
                CONTROL_TYPE_WRITE,
                (CONTROL_MODE_ACQUIRE_SWD_TARGET << 8) | CONTROL_COMMAND_PROGRAM,
                (max_attempts << 8) | (acquire_mode << 4) | psoc_type, &status, 1, 0, &transferred);

        if (retval != ERROR_OK || transferred == 0) {
                LOG_DEBUG("Zero bytes transferred");
                return ERROR_FAIL;
        }

        if (status != PROGRAMMER_OK_ACK) {
                LOG_DEBUG("Programmer did not respond OK");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_reset_target(void)
{
        int transferred;
        char status = PROGRAMMER_NOK_NACK;

        int retval = jtag_libusb_control_transfer(kitprog_handle->usb_handle,
                LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE,
                CONTROL_TYPE_WRITE,
                (CONTROL_MODE_RESET_TARGET << 8) | CONTROL_COMMAND_PROGRAM,
                0, &status, 1, 0, &transferred);

        if (retval != ERROR_OK || transferred == 0) {
                LOG_DEBUG("Zero bytes transferred");
                return ERROR_FAIL;
        }

        if (status != PROGRAMMER_OK_ACK) {
                LOG_DEBUG("Programmer did not respond OK");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_swd_sync(void)
{
        int transferred;
        char status = PROGRAMMER_NOK_NACK;

        int retval = jtag_libusb_control_transfer(kitprog_handle->usb_handle,
                LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE,
                CONTROL_TYPE_WRITE,
                (CONTROL_MODE_SYNCHRONIZE_TRANSFER << 8) | CONTROL_COMMAND_PROGRAM,
                0, &status, 1, 0, &transferred);

        if (retval != ERROR_OK || transferred == 0) {
                LOG_DEBUG("Zero bytes transferred");
                return ERROR_FAIL;
        }

        if (status != PROGRAMMER_OK_ACK) {
                LOG_DEBUG("Programmer did not respond OK");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_swd_seq(uint8_t seq_type)
{
        int transferred;
        char status = PROGRAMMER_NOK_NACK;

        int retval = jtag_libusb_control_transfer(kitprog_handle->usb_handle,
                LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE,
                CONTROL_TYPE_WRITE,
                (CONTROL_MODE_SEND_SWD_SEQUENCE << 8) | CONTROL_COMMAND_PROGRAM,
                seq_type, &status, 1, 0, &transferred);

        if (retval != ERROR_OK || transferred == 0) {
                LOG_DEBUG("Zero bytes transferred");
                return ERROR_FAIL;
        }

        if (status != PROGRAMMER_OK_ACK) {
                LOG_DEBUG("Programmer did not respond OK");
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_generic_acquire(void)
{
        const uint8_t devices[] = {DEVICE_PSOC4, DEVICE_PSOC3, DEVICE_PSOC5};

        int retval;
        int acquire_count = 0;

        /* Due to the way the SWD port is shared between the Test Controller (TC)
         * and the Cortex-M3 DAP on the PSoC 5LP, the TC is the default SWD target
         * after power is applied. To access the DAP, the PSoC 5LP requires at least
         * one acquisition sequence to be run (which switches the SWD mux from the
         * TC to the DAP). However, after the mux is switched, the Cortex-M3 will be
         * held in reset until a series of registers are written to (see section 5.2
         * of the PSoC 5LP Device Programming Specifications for details).
         *
         * Instead of writing the registers in this function, we just do what the
         * Cypress tools do and run the acquisition sequence a second time. This
         * will take the Cortex-M3 out of reset and enable debugging.
         */
        for (int i = 0; i < 2; i++) {
                for (uint8_t j = 0; j < sizeof(devices) && acquire_count == i; j++) {
                        retval = kitprog_acquire_psoc(devices[j], ACQUIRE_MODE_RESET, 3);
                        if (retval != ERROR_OK) {
                                LOG_DEBUG("Acquisition function failed for device 0x%02x.", devices[j]);
                                return retval;
                        }

                        if (kitprog_get_status() == ERROR_OK)
                                acquire_count++;
                }

                jtag_sleep(10);
        }

        if (acquire_count < 2)
                return ERROR_FAIL;

        return ERROR_OK;
}

/*************** swd wrapper functions *********************/

static int kitprog_swd_init(void)
{
        return ERROR_OK;
}

static void kitprog_swd_write_reg(uint8_t cmd, uint32_t value, uint32_t ap_delay_clk)
{
        assert(!(cmd & SWD_CMD_RNW));
        kitprog_swd_queue_cmd(cmd, NULL, value);
}

static void kitprog_swd_read_reg(uint8_t cmd, uint32_t *value, uint32_t ap_delay_clk)
{
        assert(cmd & SWD_CMD_RNW);
        kitprog_swd_queue_cmd(cmd, value, 0);
}

/*************** swd lowlevel functions ********************/

static int kitprog_swd_switch_seq(enum swd_special_seq seq)
{
        switch (seq) {
                case JTAG_TO_SWD:
                        if (kitprog_handle->supports_jtag_to_swd) {
                                LOG_DEBUG("JTAG to SWD");
                                if (kitprog_swd_seq(SEQUENCE_JTAG_TO_SWD) != ERROR_OK)
                                        return ERROR_FAIL;
                                break;
                        } else {
                                LOG_DEBUG("JTAG to SWD not supported");
                                /* Fall through to fix target reset issue */
                        }
                        /* fallthrough */
                case LINE_RESET:
                        LOG_DEBUG("SWD line reset");
                        if (kitprog_swd_seq(SEQUENCE_LINE_RESET) != ERROR_OK)
                                return ERROR_FAIL;
                        break;
                default:
                        LOG_ERROR("Sequence %d not supported.", seq);
                        return ERROR_FAIL;
        }

        return ERROR_OK;
}

static int kitprog_swd_run_queue(void)
{
        int ret;

        size_t read_count = 0;
        size_t read_index = 0;
        size_t write_count = 0;
        uint8_t *buffer = kitprog_handle->packet_buffer;

        do {
                LOG_DEBUG_IO("Executing %d queued transactions", pending_transfer_count);

                if (queued_retval != ERROR_OK) {
                        LOG_DEBUG("Skipping due to previous errors: %d", queued_retval);
                        break;
                }

                if (!pending_transfer_count)
                        break;

                for (int i = 0; i < pending_transfer_count; i++) {
                        uint8_t cmd = pending_transfers[i].cmd;
                        uint32_t data = pending_transfers[i].data;

                        /* When proper WAIT handling is implemented in the
                         * common SWD framework, this kludge can be
                         * removed. However, this might lead to minor
                         * performance degradation as the adapter wouldn't be
                         * able to automatically retry anything (because ARM
                         * has forgotten to implement sticky error flags
                         * clearing). See also comments regarding
                         * cmsis_dap_cmd_DAP_TFER_Configure() and
                         * cmsis_dap_cmd_DAP_SWD_Configure() in
                         * cmsis_dap_init().
                         */
                        if (!(cmd & SWD_CMD_RNW) &&
                                !(cmd & SWD_CMD_APNDP) &&
                                (cmd & SWD_CMD_A32) >> 1 == DP_CTRL_STAT &&
                                (data & CORUNDETECT)) {
                                LOG_DEBUG("refusing to enable sticky overrun detection");
                                data &= ~CORUNDETECT;
                        }

                        LOG_DEBUG_IO("%s %s reg %x %"PRIx32,
                                        cmd & SWD_CMD_APNDP ? "AP" : "DP",
                                        cmd & SWD_CMD_RNW ? "read" : "write",
                                  (cmd & SWD_CMD_A32) >> 1, data);

                        buffer[write_count++] = (cmd | SWD_CMD_START | SWD_CMD_PARK) & ~SWD_CMD_STOP;
                        read_count++;
                        if (!(cmd & SWD_CMD_RNW)) {
                                buffer[write_count++] = (data) & 0xff;
                                buffer[write_count++] = (data >> 8) & 0xff;
                                buffer[write_count++] = (data >> 16) & 0xff;
                                buffer[write_count++] = (data >> 24) & 0xff;
                        } else {
                                read_count += 4;
                        }
                }

                if (jtag_libusb_bulk_write(kitprog_handle->usb_handle,
                                           BULK_EP_OUT, (char *)buffer,
                                           write_count, 0, &ret)) {
                        LOG_ERROR("Bulk write failed");
                        queued_retval = ERROR_FAIL;
                        break;
                } else {
                        queued_retval = ERROR_OK;
                }

                /* KitProg firmware does not send a zero length packet
                 * after the bulk-in transmission of a length divisible by bulk packet
                 * size (64 bytes) as required by the USB specification.
                 * Therefore libusb would wait for continuation of transmission.
                 * Workaround: Limit bulk read size to expected number of bytes
                 * for problematic transfer sizes. Otherwise use the maximum buffer
                 * size here because the KitProg sometimes doesn't like bulk reads
                 * of fewer than 62 bytes. (?!?!)
                 */
                size_t read_count_workaround = SWD_MAX_BUFFER_LENGTH;
                if (read_count % 64 == 0)
                        read_count_workaround = read_count;

                if (jtag_libusb_bulk_read(kitprog_handle->usb_handle,
                                BULK_EP_IN | LIBUSB_ENDPOINT_IN, (char *)buffer,
                                read_count_workaround, 1000, &ret)) {
                        LOG_ERROR("Bulk read failed");
                        queued_retval = ERROR_FAIL;
                        break;
                } else {
                        /* Handle garbage data by offsetting the initial read index */
                        if ((unsigned int)ret > read_count)
                                read_index = ret - read_count;
                        queued_retval = ERROR_OK;
                }

                for (int i = 0; i < pending_transfer_count; i++) {
                        if (pending_transfers[i].cmd & SWD_CMD_RNW) {
                                uint32_t data = le_to_h_u32(&buffer[read_index]);

                                LOG_DEBUG_IO("Read result: %"PRIx32, data);

                                if (pending_transfers[i].buffer)
                                        *(uint32_t *)pending_transfers[i].buffer = data;

                                read_index += 4;
                        }

                        uint8_t ack = buffer[read_index] & 0x07;
                        if (ack != SWD_ACK_OK || (buffer[read_index] & 0x08)) {
                                LOG_DEBUG("SWD ack not OK: %d %s", i,
                                          ack == SWD_ACK_WAIT ? "WAIT" : ack == SWD_ACK_FAULT ? "FAULT" : "JUNK");
                                queued_retval = swd_ack_to_error_code(ack);
                                break;
                        }
                        read_index++;
                }
        } while (0);

        pending_transfer_count = 0;
        int retval = queued_retval;
        queued_retval = ERROR_OK;

        return retval;
}

static void kitprog_swd_queue_cmd(uint8_t cmd, uint32_t *dst, uint32_t data)
{
        if (pending_transfer_count == pending_queue_len) {
                /* Not enough room in the queue. Run the queue. */
                queued_retval = kitprog_swd_run_queue();
        }

        if (queued_retval != ERROR_OK)
                return;

        pending_transfers[pending_transfer_count].data = data;
        pending_transfers[pending_transfer_count].cmd = cmd;
        if (cmd & SWD_CMD_RNW) {
                /* Queue a read transaction */
                pending_transfers[pending_transfer_count].buffer = dst;
        }
        pending_transfer_count++;
}

/*************** jtag lowlevel functions ********************/

static int kitprog_reset(int trst, int srst)
{
        int retval = ERROR_OK;

        if (trst == 1) {
                LOG_ERROR("KitProg: Interface has no TRST");
                return ERROR_FAIL;
        }

        if (srst == 1) {
                retval = kitprog_reset_target();
                /* Since the previous command also disables SWCLK output, we need to send an
                 * SWD bus reset command to re-enable it. For some reason, running
                 * kitprog_swd_seq() immediately after kitprog_reset_target() won't
                 * actually fix this. Instead, kitprog_swd_seq() will be run once OpenOCD
                 * tries to send a JTAG-to-SWD sequence, which should happen during
                 * swd_check_reconnect (see the JTAG_TO_SWD case in kitprog_swd_switch_seq).
                 */
        }

        if (retval != ERROR_OK)
                LOG_ERROR("KitProg: Interface reset failed");
        return retval;
}

COMMAND_HANDLER(kitprog_handle_info_command)
{
        int retval = kitprog_get_info();

        return retval;
}


COMMAND_HANDLER(kitprog_handle_acquire_psoc_command)
{
        int retval = kitprog_generic_acquire();

        return retval;
}

COMMAND_HANDLER(kitprog_handle_init_acquire_psoc_command)
{
        kitprog_init_acquire_psoc = true;

        return ERROR_OK;
}

static const struct command_registration kitprog_subcommand_handlers[] = {
        {
                .name = "info",
                .handler = &kitprog_handle_info_command,
                .mode = COMMAND_EXEC,
                .usage = "",
                .help = "show KitProg info",
        },
        {
                .name = "acquire_psoc",
                .handler = &kitprog_handle_acquire_psoc_command,
                .mode = COMMAND_EXEC,
                .usage = "",
                .help = "try to acquire a PSoC",
        },
        {
                .name = "init_acquire_psoc",
                .handler = &kitprog_handle_init_acquire_psoc_command,
                .mode = COMMAND_CONFIG,
                .help = "try to acquire a PSoC during init",
                .usage = "",
        },
        COMMAND_REGISTRATION_DONE
};

static const struct command_registration kitprog_command_handlers[] = {
        {
                .name = "kitprog",
                .mode = COMMAND_ANY,
                .help = "perform KitProg management",
                .usage = "<cmd>",
                .chain = kitprog_subcommand_handlers,
        },
        COMMAND_REGISTRATION_DONE
};

static const struct swd_driver kitprog_swd = {
        .init = kitprog_swd_init,
        .switch_seq = kitprog_swd_switch_seq,
        .read_reg = kitprog_swd_read_reg,
        .write_reg = kitprog_swd_write_reg,
        .run = kitprog_swd_run_queue,
};

static const char * const kitprog_transports[] = { "swd", NULL };

struct adapter_driver kitprog_adapter_driver = {
        .name = "kitprog",
        .transports = kitprog_transports,
        .commands = kitprog_command_handlers,

        .init = kitprog_init,
        .quit = kitprog_quit,
        .reset = kitprog_reset,

        .swd_ops = &kitprog_swd,
};