/* -*- c++ -*- */

/*

 * Copyright 2003,2004,2006 Free Software Foundation, Inc.

 * 

 * This file is part of GNU Radio

 * 

 * GNU Radio 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 3, or (at your option)

 * any later version.

 * 

 * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to

 * the Free Software Foundation, Inc., 51 Franklin Street,

 * Boston, MA 02110-1301, USA.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include "usrp_prims.h"

#include "usrp_commands.h"

#include "usrp_ids.h"

#include "usrp_i2c_addr.h"

#include "fpga_regs_common.h"

#include "fpga_regs_standard.h"

#include <usb.h>

#include <errno.h>

#include <stdio.h>

#include <unistd.h>

#include <stdlib.h>

#include <string.h>

#include <ctype.h>

#include <time.h>                // FIXME should check with autoconf (nanosleep)

#include <algorithm>

#include <ad9862.h>

#include <assert.h>

extern "C" {

#include "md5.h"

};

#define VERBOSE 0

using namespace ad9862;

static const int FIRMWARE_HASH_SLOT        = 0;

static const int FPGA_HASH_SLOT         = 1;

static const int hash_slot_addr[2] = {

  USRP_HASH_SLOT_0_ADDR,

  USRP_HASH_SLOT_1_ADDR

};

static const char *default_firmware_filename = "std.ihx";

static const char *default_fpga_filename     = "std_2rxhb_2tx.rbf";

#include "std_paths.h"

#include <stdio.h>

static char *

find_file (const char *filename, int hw_rev)

{

  const char **sp = std_paths;

  static char path[1000];

  char *s;

  s = getenv("USRP_PATH");

  if (s) {

    snprintf (path, sizeof (path), "%s/rev%d/%s", s, hw_rev, filename);

    if (access (path, R_OK) == 0)

      return path;

  }

  while (*sp){

    snprintf (path, sizeof (path), "%s/rev%d/%s", *sp, hw_rev, filename);

    if (access (path, R_OK) == 0)

      return path;

    sp++;

  }

  return 0;

}

static const char *

get_proto_filename(const std::string user_filename, const char *env_var, const char *def)

{

  if (user_filename.length() != 0)

    return user_filename.c_str();

  char *s = getenv(env_var);

  if (s && *s)

    return s;

  return def;

}

static void power_down_9862s (struct usb_dev_handle *udh);

void

usrp_one_time_init ()

{

  static bool first = true;

  if (first){

    first = false;

    usb_init ();                        // usb library init

    usb_find_busses ();

    usb_find_devices ();

  }

}

void

usrp_rescan ()

{

  usb_find_busses ();

  usb_find_devices ();

}

// ----------------------------------------------------------------

// Danger, big, fragile KLUDGE.  The problem is that we want to be

// able to get from a usb_dev_handle back to a usb_device, and the

// right way to do this is buried in a non-installed include file.

static struct usb_device *

dev_handle_to_dev (usb_dev_handle *udh)

{

  struct usb_dev_handle_kludge {

    int                         fd;

    struct usb_bus        *bus;

    struct usb_device        *device;

  };

  return ((struct usb_dev_handle_kludge *) udh)->device;

}

// ----------------------------------------------------------------

/*

 * q must be a real USRP, not an FX2.  Return its hardware rev number.

 */

int

usrp_hw_rev (struct usb_device *q)

{

  return q->descriptor.bcdDevice & 0x00FF;

}

/*

 * q must be a real USRP, not an FX2.  Return true if it's configured.

 */

static bool

_usrp_configured_p (struct usb_device *q)

{

  return (q->descriptor.bcdDevice & 0xFF00) != 0;

}

bool

usrp_usrp_p (struct usb_device *q)

{

  return (q->descriptor.idVendor == USB_VID_FSF

          && q->descriptor.idProduct == USB_PID_FSF_USRP);

}

bool

usrp_fx2_p (struct usb_device *q)

{

  return (q->descriptor.idVendor == USB_VID_CYPRESS

          && q->descriptor.idProduct == USB_PID_CYPRESS_FX2);

}

bool

usrp_usrp0_p (struct usb_device *q)

{

  return usrp_usrp_p (q) && usrp_hw_rev (q) == 0;

}

bool

usrp_usrp1_p (struct usb_device *q)

{

  return usrp_usrp_p (q) && usrp_hw_rev (q) == 1;

}

bool

usrp_usrp2_p (struct usb_device *q)

{

  return usrp_usrp_p (q) && usrp_hw_rev (q) == 2;

}

bool

usrp_unconfigured_usrp_p (struct usb_device *q)

{

  return usrp_usrp_p (q) && !_usrp_configured_p (q);

}

bool

usrp_configured_usrp_p (struct usb_device *q)

{

  return usrp_usrp_p (q) && _usrp_configured_p (q);

}

// ----------------------------------------------------------------

struct usb_device *

usrp_find_device (int nth, bool fx2_ok_p)

{

  struct usb_bus *p;

  struct usb_device *q;

  int         n_found = 0;

  usrp_one_time_init ();

  p = usb_get_busses();

  while (p != NULL){

    q = p->devices;

    while (q != NULL){

      if (usrp_usrp_p (q) || (fx2_ok_p && usrp_fx2_p (q))){

        if (n_found == nth)        // return this one

          return q;

        n_found++;                // keep looking

      }

      q = q->next;

    }

    p = p->next;

  }

  return 0;        // not found

}

static struct usb_dev_handle *

usrp_open_interface (struct usb_device *dev, int interface, int altinterface)

{

  struct usb_dev_handle *udh = usb_open (dev);

  if (udh == 0)

    return 0;

  if (dev != dev_handle_to_dev (udh)){

    fprintf (stderr, "%s:%d: internal error!\n", __FILE__, __LINE__);

    abort ();

  }

#if defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)

  // There's no get get_configuration function, and with some of the newer kernels

  // setting the configuration, even if to the same value, hoses any other processes

  // that have it open.  Hence we opt to not set it at all (We've only

  // got a single configuration anyway).  This may hose the win32 stuff...

  // Appears to be required for libusb-win32 and Cygwin -- dew 09/20/06

  if (usb_set_configuration (udh, 1) < 0){

    /*

     * Ignore this error.  

     *

     * Seems that something changed in drivers/usb/core/devio.c:proc_setconfig such that

     * it returns -EBUSY if _any_ of the interfaces of a device are open.

     * We've only got a single configuration, so setting it doesn't even seem

     * like it should be required.

     */

  }

#endif

  if (usb_claim_interface (udh, interface) < 0){

    fprintf (stderr, "%s:usb_claim_interface: failed interface %d\n", __FUNCTION__,interface);

    fprintf (stderr, "%s\n", usb_strerror());

    usb_close (udh);

    return 0;

  }

  if (usb_set_altinterface (udh, altinterface) < 0){

    fprintf (stderr, "%s:usb_set_alt_interface: failed\n", __FUNCTION__);

    fprintf (stderr, "%s\n", usb_strerror());

    usb_release_interface (udh, interface);

    usb_close (udh);

    return 0;

  }

  return udh;

}

struct usb_dev_handle *

usrp_open_cmd_interface (struct usb_device *dev)

{

  return usrp_open_interface (dev, USRP_CMD_INTERFACE, USRP_CMD_ALTINTERFACE);

}

struct usb_dev_handle *

usrp_open_rx_interface (struct usb_device *dev)

{

  return usrp_open_interface (dev, USRP_RX_INTERFACE, USRP_RX_ALTINTERFACE);

}

struct usb_dev_handle *

usrp_open_tx_interface (struct usb_device *dev)

{

  return usrp_open_interface (dev, USRP_TX_INTERFACE, USRP_TX_ALTINTERFACE);

}

bool

usrp_close_interface (struct usb_dev_handle *udh)

{

  // we're assuming that closing an interface automatically releases it.

  return usb_close (udh) == 0;

}

// ----------------------------------------------------------------

// write internal ram using Cypress vendor extension

static bool

write_internal_ram (struct usb_dev_handle *udh, unsigned char *buf,

                    int start_addr, size_t len)

{

  int addr;

  int n;

  int a;

  int quanta = MAX_EP0_PKTSIZE;

  for (addr = start_addr; addr < start_addr + (int) len; addr += quanta){

    n = len + start_addr - addr;

    if (n > quanta)

      n = quanta;

    a = usb_control_msg (udh, 0x40, 0xA0,

                         addr, 0, (char *)(buf + (addr - start_addr)), n, 1000);

    if (a < 0){

      fprintf(stderr,"write_internal_ram failed: %s\n", usb_strerror());

      return false;

    }

  }

  return true;

}

// ----------------------------------------------------------------

// whack the CPUCS register using the upload RAM vendor extension

static bool

reset_cpu (struct usb_dev_handle *udh, bool reset_p)

{

  unsigned char v;

  if (reset_p)

    v = 1;                // hold processor in reset

  else

    v = 0;                // release reset

  return write_internal_ram (udh, &v, 0xE600, 1);

}

// ----------------------------------------------------------------

// Load intel format file into cypress FX2 (8051)

static bool

_usrp_load_firmware (struct usb_dev_handle *udh, const char *filename,

                     unsigned char hash[USRP_HASH_SIZE])

{

  FILE        *f = fopen (filename, "ra");

  if (f == 0){

    perror (filename);

    return false;

  }

  if (!reset_cpu (udh, true))        // hold CPU in reset while loading firmware

    goto fail;

  char s[1024];

  int length;

  int addr;

  int type;

  unsigned char data[256];

  unsigned char checksum, a;

  unsigned int b;

  int i;

  while (!feof(f)){

    fgets(s, sizeof (s), f); /* we should not use more than 263 bytes normally */

    if(s[0]!=':'){

      fprintf(stderr,"%s: invalid line: \"%s\"\n", filename, s);

      goto fail;

    }

    sscanf(s+1, "%02x", &length);

    sscanf(s+3, "%04x", &addr);

    sscanf(s+7, "%02x", &type);

    if(type==0){

      a=length+(addr &0xff)+(addr>>8)+type;

      for(i=0;i<length;i++){

        sscanf (s+9+i*2,"%02x", &b);

        data[i]=b;

        a=a+data[i];

      }

      sscanf (s+9+length*2,"%02x", &b);

      checksum=b;

      if (((a+checksum)&0xff)!=0x00){

        fprintf (stderr, "  ** Checksum failed: got 0x%02x versus 0x%02x\n", (-a)&0xff, checksum);

        goto fail;

      }

      if (!write_internal_ram (udh, data, addr, length))

        goto fail;

    }

    else if (type == 0x01){      // EOF

      break;

    }

    else if (type == 0x02){

      fprintf(stderr, "Extended address: whatever I do with it?\n");

      fprintf (stderr, "%s: invalid line: \"%s\"\n", filename, s);

      goto fail;

    }

  }

  // we jam the hash value into the FX2 memory before letting

  // the cpu out of reset.  When it comes out of reset it

  // may renumerate which will invalidate udh.

  if (!usrp_set_hash (udh, FIRMWARE_HASH_SLOT, hash))

    fprintf (stderr, "usrp: failed to write firmware hash slot\n");

  if (!reset_cpu (udh, false))                // take CPU out of reset

    goto fail;

  fclose (f);

  return true;

 fail:

  fclose (f);

  return false;

}

// ----------------------------------------------------------------

// write vendor extension command to USRP

static int

write_cmd (struct usb_dev_handle *udh,

           int request, int value, int index,

           unsigned char *bytes, int len)

{

  int        requesttype = (request & 0x80) ? VRT_VENDOR_IN : VRT_VENDOR_OUT;

  int r = usb_control_msg (udh, requesttype, request, value, index,

                           (char *) bytes, len, 1000);

  if (r < 0){

    // we get EPIPE if the firmware stalls the endpoint.

    if (errno != EPIPE)

      fprintf (stderr, "usb_control_msg failed: %s\n", usb_strerror ());

  }

  return r;

}

// ----------------------------------------------------------------

// load fpga

static bool

_usrp_load_fpga (struct usb_dev_handle *udh, const char *filename,

                 unsigned char hash[USRP_HASH_SIZE])

{

  bool ok = true;

  FILE        *fp = fopen (filename, "rb");

  if (fp == 0){

    perror (filename);

    return false;

  }

  unsigned char buf[MAX_EP0_PKTSIZE];        // 64 is max size of EP0 packet on FX2

  int n;

  usrp_set_led (udh, 1, 1);                // led 1 on

  // reset FPGA (and on rev1 both AD9862's, thus killing clock)

  usrp_set_fpga_reset (udh, 1);                // hold fpga in reset

  if (write_cmd (udh, VRQ_FPGA_LOAD, 0, FL_BEGIN, 0, 0) != 0)

    goto fail;

  while ((n = fread (buf, 1, sizeof (buf), fp)) > 0){

    if (write_cmd (udh, VRQ_FPGA_LOAD, 0, FL_XFER, buf, n) != n)

      goto fail;

  }

  if (write_cmd (udh, VRQ_FPGA_LOAD, 0, FL_END, 0, 0) != 0)

    goto fail;

  fclose (fp);

  if (!usrp_set_hash (udh, FPGA_HASH_SLOT, hash))

    fprintf (stderr, "usrp: failed to write fpga hash slot\n");

  // On the rev1 USRP, the {tx,rx}_{enable,reset} bits are

  // controlled over the serial bus, and hence aren't observed until

  // we've got a good fpga bitstream loaded.

  usrp_set_fpga_reset (udh, 0);                // fpga out of master reset

  // now these commands will work

  ok &= usrp_set_fpga_tx_enable (udh, 0);

  ok &= usrp_set_fpga_rx_enable (udh, 0);

  ok &= usrp_set_fpga_tx_reset (udh, 1);        // reset tx and rx paths

  ok &= usrp_set_fpga_rx_reset (udh, 1);

  ok &= usrp_set_fpga_tx_reset (udh, 0);        // reset tx and rx paths

  ok &= usrp_set_fpga_rx_reset (udh, 0);

  if (!ok)

    fprintf (stderr, "usrp: failed to reset tx and/or rx path\n");

  // Manually reset all regs except master control to zero.

  // FIXME may want to remove this when we rework FPGA reset strategy.

  // In the mean while, this gets us reproducible behavior.

  for (int i = 0; i < FR_USER_0; i++){

    if (i == FR_MASTER_CTRL)

      continue;

    usrp_write_fpga_reg(udh, i, 0);

  }

  power_down_9862s (udh);                // on the rev1, power these down!

  usrp_set_led (udh, 1, 0);                // led 1 off

  return true;

 fail:

  power_down_9862s (udh);                // on the rev1, power these down!

  fclose (fp);

  return false;

}

// ----------------------------------------------------------------

bool 

usrp_set_led (struct usb_dev_handle *udh, int which, bool on)

{

  int r = write_cmd (udh, VRQ_SET_LED, on, which, 0, 0);

  return r == 0;

}

bool

usrp_set_hash (struct usb_dev_handle *udh, int which,

               const unsigned char hash[USRP_HASH_SIZE])

{

  which &= 1;

  // we use the Cypress firmware down load command to jam it in.

  int r = usb_control_msg (udh, 0x40, 0xa0, hash_slot_addr[which], 0,

                           (char *) hash, USRP_HASH_SIZE, 1000);

  return r == USRP_HASH_SIZE;

}

bool

usrp_get_hash (struct usb_dev_handle *udh, int which, 

               unsigned char hash[USRP_HASH_SIZE])

{

  which &= 1;

  // we use the Cypress firmware upload command to fetch it.

  int r = usb_control_msg (udh, 0xc0, 0xa0, hash_slot_addr[which], 0,

                           (char *) hash, USRP_HASH_SIZE, 1000);

  return r == USRP_HASH_SIZE;

}

static bool

usrp_set_switch (struct usb_dev_handle *udh, int cmd_byte, bool on)

{

  return write_cmd (udh, cmd_byte, on, 0, 0, 0) == 0;

}

static bool

usrp1_fpga_write (struct usb_dev_handle *udh,

                  int regno, int value)

{

  // on the rev1 usrp, we use the generic spi_write interface

  unsigned char buf[4];

  buf[0] = (value >> 24) & 0xff;        // MSB first

  buf[1] = (value >> 16) & 0xff;

  buf[2] = (value >>  8) & 0xff;

  buf[3] = (value >>  0) & 0xff;

  return usrp_spi_write (udh, 0x00 | (regno & 0x7f),

                         SPI_ENABLE_FPGA,

                         SPI_FMT_MSB | SPI_FMT_HDR_1,

                         buf, sizeof (buf));

}

static bool

usrp1_fpga_read (struct usb_dev_handle *udh,

                 int regno, int *value)

{

  *value = 0;

  unsigned char buf[4];

  bool ok = usrp_spi_read (udh, 0x80 | (regno & 0x7f),

                           SPI_ENABLE_FPGA,

                           SPI_FMT_MSB | SPI_FMT_HDR_1,

                           buf, sizeof (buf));

  if (ok)

    *value = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];

  return ok;

}

bool

usrp_write_fpga_reg (struct usb_dev_handle *udh, int reg, int value)

{

  switch (usrp_hw_rev (dev_handle_to_dev (udh))){

  case 0:                        // not supported ;)

    abort();        

  default:

    return usrp1_fpga_write (udh, reg, value);

  }

}

bool

usrp_read_fpga_reg (struct usb_dev_handle *udh, int reg, int *value)

{

  switch (usrp_hw_rev (dev_handle_to_dev (udh))){

  case 0:                // not supported ;)

    abort();

  default:

    return usrp1_fpga_read (udh, reg, value);

  }

}

bool 

usrp_set_fpga_reset (struct usb_dev_handle *udh, bool on)

{

  return usrp_set_switch (udh, VRQ_FPGA_SET_RESET, on);

}

bool 

usrp_set_fpga_tx_enable (struct usb_dev_handle *udh, bool on)

{

  return usrp_set_switch (udh, VRQ_FPGA_SET_TX_ENABLE, on);

}

bool 

usrp_set_fpga_rx_enable (struct usb_dev_handle *udh, bool on)

{

  return usrp_set_switch (udh, VRQ_FPGA_SET_RX_ENABLE, on);

}

bool 

usrp_set_fpga_tx_reset (struct usb_dev_handle *udh, bool on)

{

  return usrp_set_switch (udh, VRQ_FPGA_SET_TX_RESET, on);

}

bool 

usrp_set_fpga_rx_reset (struct usb_dev_handle *udh, bool on)

{

  return usrp_set_switch (udh, VRQ_FPGA_SET_RX_RESET, on);

}

// ----------------------------------------------------------------

// conditional load stuff

static bool

compute_hash (const char *filename, unsigned char hash[USRP_HASH_SIZE])

{

  assert (USRP_HASH_SIZE == 16);

  memset (hash, 0, USRP_HASH_SIZE);

  FILE *fp = fopen (filename, "rb");

  if (fp == 0){

    perror (filename);

    return false;

  }

  int r = md5_stream (fp, hash);

  fclose (fp);

  return r == 0;

}

static usrp_load_status_t

usrp_conditionally_load_something (struct usb_dev_handle *udh,

                                   const char *filename,

                                   bool force,

                                   int slot,

                                   bool loader (struct usb_dev_handle *,

                                                const char *,

                                                unsigned char [USRP_HASH_SIZE]))

{

  unsigned char file_hash[USRP_HASH_SIZE];

  unsigned char usrp_hash[USRP_HASH_SIZE];

  if (access (filename, R_OK) != 0){

    perror (filename);

    return ULS_ERROR;

  }

  if (!compute_hash (filename, file_hash))

    return ULS_ERROR;

  if (!force

      && usrp_get_hash (udh, slot, usrp_hash)

      && memcmp (file_hash, usrp_hash, USRP_HASH_SIZE) == 0)

    return ULS_ALREADY_LOADED;

  bool r = loader (udh, filename, file_hash);

  if (!r)

    return ULS_ERROR;

  return ULS_OK;

}

usrp_load_status_t

usrp_load_firmware (struct usb_dev_handle *udh,

                    const char *filename,

                    bool force)

{

  return usrp_conditionally_load_something (udh, filename, force,

                                            FIRMWARE_HASH_SLOT,

                                            _usrp_load_firmware);

}

usrp_load_status_t

usrp_load_fpga (struct usb_dev_handle *udh,

                const char *filename,

                bool force)

{

  return usrp_conditionally_load_something (udh, filename, force,

                                            FPGA_HASH_SLOT,

                                            _usrp_load_fpga);

}

static usb_dev_handle *

open_nth_cmd_interface (int nth)

{

  struct usb_device *udev = usrp_find_device (nth);

  if (udev == 0){

    fprintf (stderr, "usrp: failed to find usrp[%d]\n", nth);

    return 0;

  }

  struct usb_dev_handle *udh;

  udh = usrp_open_cmd_interface (udev);

  if (udh == 0){

    // FIXME this could be because somebody else has it open.

    // We should delay and retry...

    fprintf (stderr, "open_nth_cmd_interface: open_cmd_interface failed\n");

    usb_strerror ();

    return 0;

  }

  return udh;

 }

static bool

our_nanosleep (const struct timespec *delay)

{

  struct timespec        new_delay = *delay;

  struct timespec        remainder;

  while (1){

    int r = nanosleep (&new_delay, &remainder);

    if (r == 0)

      return true;

    if (errno == EINTR)

      new_delay = remainder;

    else {

      perror ("nanosleep");

      return false;

    }

  }

}

static bool

mdelay (int millisecs)

{

  struct timespec        ts;

  ts.tv_sec = millisecs / 1000;

  ts.tv_nsec = (millisecs - (1000 * ts.tv_sec)) * 1000000;

  return our_nanosleep (&ts);

}

usrp_load_status_t

usrp_load_firmware_nth (int nth, const char *filename, bool force){

  struct usb_dev_handle *udh = open_nth_cmd_interface (nth);

  if (udh == 0)

    return ULS_ERROR;

  usrp_load_status_t s = usrp_load_firmware (udh, filename, force);

  usrp_close_interface (udh);

  switch (s){

  case ULS_ALREADY_LOADED:                // nothing changed...

    return ULS_ALREADY_LOADED;

    break;

  case ULS_OK:

    // we loaded firmware successfully.

    // It's highly likely that the board will renumerate (simulate a

    // disconnect/reconnect sequence), invalidating our current

    // handle.

    // FIXME.  Turn this into a loop that rescans until we refind ourselves

    struct timespec        t;        // delay for 1 second

    t.tv_sec = 2;

    t.tv_nsec = 0;

    our_nanosleep (&t);

    usb_find_busses ();                // rescan busses and devices

    usb_find_devices ();

    return ULS_OK;

  default:

  case ULS_ERROR:                // some kind of problem

    return ULS_ERROR;

  }

}

static void

load_status_msg (usrp_load_status_t s, const char *type, const char *filename)

{

  char *e = getenv("USRP_VERBOSE");

  bool verbose = e != 0;

  switch (s){

  case ULS_ERROR:

    fprintf (stderr, "usrp: failed to load %s %s.\n", type, filename);

    break;

  case ULS_ALREADY_LOADED:

    if (verbose)

      fprintf (stderr, "usrp: %s %s already loaded.\n", type, filename);

    break;

  case ULS_OK:

    if (verbose)

      fprintf (stderr, "usrp: %s %s loaded successfully.\n", type, filename);

    break;

  }

}

bool

usrp_load_standard_bits (int nth, bool force,

                         const std::string fpga_filename,

                         const std::string firmware_filename)

{

  usrp_load_status_t         s;

  const char                *filename;

  const char                *proto_filename;

  int hw_rev;

  // first, figure out what hardware rev we're dealing with

  {

    struct usb_device *udev = usrp_find_device (nth);

    if (udev == 0){

      fprintf (stderr, "usrp: failed to find usrp[%d]\n", nth);

      return false;

    }

    hw_rev = usrp_hw_rev (udev);

  }

  // start by loading the firmware

  proto_filename = get_proto_filename(firmware_filename, "USRP_FIRMWARE",

                                      default_firmware_filename);

  filename = find_file(proto_filename, hw_rev);

  if (filename == 0){

    fprintf (stderr, "Can't find firmware: %s\n", proto_filename);

    return false;

  }

  s = usrp_load_firmware_nth (nth, filename, force);

  load_status_msg (s, "firmware", filename);

  if (s == ULS_ERROR)

    return false;

  // if we actually loaded firmware, we must reload fpga ...

  if (s == ULS_OK)

    force = true;

  // now move on to the fpga configuration bitstream

  proto_filename = get_proto_filename(fpga_filename, "USRP_FPGA",

                                      default_fpga_filename);

  filename = find_file (proto_filename, hw_rev);

  if (filename == 0){

    fprintf (stderr, "Can't find fpga bitstream: %s\n", proto_filename);

    return false;

  }

  struct usb_dev_handle *udh = open_nth_cmd_interface (nth);

  if (udh == 0)

    return false;

  s = usrp_load_fpga (udh, filename, force);

  usrp_close_interface (udh);

  load_status_msg (s, "fpga bitstream", filename);

  if (s == ULS_ERROR)

    return false;

  return true;

}

bool

_usrp_get_status (struct usb_dev_handle *udh, int which, bool *trouble)

{

  unsigned char        status;

  *trouble = true;

  if (write_cmd (udh, VRQ_GET_STATUS, 0, which,

                 &status, sizeof (status)) != sizeof (status))

    return false;

  *trouble = status;

  return true;

}

bool

usrp_check_rx_overrun (struct usb_dev_handle *udh, bool *overrun_p)

{

  return _usrp_get_status (udh, GS_RX_OVERRUN, overrun_p);

}

bool

usrp_check_tx_underrun (struct usb_dev_handle *udh, bool *underrun_p)

{

  return _usrp_get_status (udh, GS_TX_UNDERRUN, underrun_p);

}

bool

usrp_i2c_write (struct usb_dev_handle *udh, int i2c_addr,

                const void *buf, int len)

{

  if (len < 1 || len > MAX_EP0_PKTSIZE)

    return false;

  return write_cmd (udh, VRQ_I2C_WRITE, i2c_addr, 0,

                    (unsigned char *) buf, len) == len;

}

bool

usrp_i2c_read (struct usb_dev_handle *udh, int i2c_addr,

               void *buf, int len)

{

  if (len < 1 || len > MAX_EP0_PKTSIZE)

    return false;

  return write_cmd (udh, VRQ_I2C_READ, i2c_addr, 0,

                    (unsigned char *) buf, len) == len;

}

bool

usrp_spi_write (struct usb_dev_handle *udh,

                int optional_header, int enables, int format,

                const void *buf, int len)

{

  if (len < 0 || len > MAX_EP0_PKTSIZE)

    return false;

  return write_cmd (udh, VRQ_SPI_WRITE,

                    optional_header,

                    ((enables & 0xff) << 8) | (format & 0xff),

                    (unsigned char *) buf, len) == len;

}

bool

usrp_spi_read (struct usb_dev_handle *udh,

               int optional_header, int enables, int format,

               void *buf, int len)

{

  if (len < 0 || len > MAX_EP0_PKTSIZE)

    return false;

  return write_cmd (udh, VRQ_SPI_READ,

                    optional_header,

                    ((enables & 0xff) << 8) | (format & 0xff),

                    (unsigned char *) buf, len) == len;

}

bool

usrp_9862_write (struct usb_dev_handle *udh, int which_codec,

                 int regno, int value)

{

  if (0)

    fprintf (stderr, "usrp_9862_write which = %d, reg = %2d, val = %3d (0x%02x)\n",

             which_codec, regno, value, value);

  unsigned char buf[1];

  buf[0] = value;

  return usrp_spi_write (udh, 0x00 | (regno & 0x3f),

                         which_codec == 0 ? SPI_ENABLE_CODEC_A : SPI_ENABLE_CODEC_B,

                         SPI_FMT_MSB | SPI_FMT_HDR_1,

                         buf, 1);

}

bool

usrp_9862_read (struct usb_dev_handle *udh, int which_codec,

                int regno, unsigned char *value)

{

  return usrp_spi_read (udh, 0x80 | (regno & 0x3f),

                        which_codec == 0 ? SPI_ENABLE_CODEC_A : SPI_ENABLE_CODEC_B,

                        SPI_FMT_MSB | SPI_FMT_HDR_1,

                        value, 1);

}

bool

usrp_9862_write_many (struct usb_dev_handle *udh,

                      int which_codec,

                      const unsigned char *buf,

                      int len)

{

  if (len & 0x1)

    return false;                // must be even

  bool result = true;

  while (len > 0){

    result &= usrp_9862_write (udh, which_codec, buf[0], buf[1]);

    len -= 2;

    buf += 2;

  }

  return result;

}

bool

usrp_9862_write_many_all (struct usb_dev_handle *udh,

                           const unsigned char *buf, int len)

{

  // FIXME handle 2/2 and 4/4 versions

  bool result;

  result  = usrp_9862_write_many (udh, 0, buf, len);

  result &= usrp_9862_write_many (udh, 1, buf, len);

  return result;

}

static void

power_down_9862s (struct usb_dev_handle *udh)

{

  static const unsigned char regs[] = {

    REG_RX_PWR_DN,        0x01,                        // everything

    REG_TX_PWR_DN,        0x0f,                        // pwr dn digital and analog_both

    REG_TX_MODULATOR,        0x00                        // coarse & fine modulators disabled

  };

  switch (usrp_hw_rev (dev_handle_to_dev (udh))){

  case 0:

    break;

  default:

    usrp_9862_write_many_all (udh, regs, sizeof (regs));

    break;

  }

}

static const int EEPROM_PAGESIZE = 16;

bool

usrp_eeprom_write (struct usb_dev_handle *udh, int i2c_addr,

                   int eeprom_offset, const void *buf, int len)

{

  unsigned char cmd[2];

  const unsigned char *p = (unsigned char *) buf;

  // The simplest thing that could possibly work:

  //   all writes are single byte writes.

  //

  // We could speed this up using the page write feature,

  // but we write so infrequently, why bother...

  while (len-- > 0){

    cmd[0] = eeprom_offset++;

    cmd[1] = *p++;

    bool r = usrp_i2c_write (udh, i2c_addr, cmd, sizeof (cmd));

    mdelay (10);                // delay 10ms worst case write time

    if (!r)

      return false;

  }

  return true;

}

bool

usrp_eeprom_read (struct usb_dev_handle *udh, int i2c_addr,

                  int eeprom_offset, void *buf, int len)

{

  unsigned char *p = (unsigned char *) buf;

  // We setup a random read by first doing a "zero byte write".

  // Writes carry an address.  Reads use an implicit address.

  unsigned char cmd[1];

  cmd[0] = eeprom_offset;

  if (!usrp_i2c_write (udh, i2c_addr, cmd, sizeof (cmd)))

    return false;

  while (len > 0){

    int n = std::min (len, MAX_EP0_PKTSIZE);

    if (!usrp_i2c_read (udh, i2c_addr, p, n))

      return false;

    len -= n;

    p += n;

  }

  return true;

}

// ----------------------------------------------------------------

static bool

slot_to_codec (int slot, int *which_codec)

{

  *which_codec = 0;

  switch (slot){

  case SLOT_TX_A:

  case SLOT_RX_A:

    *which_codec = 0;

    break;

  case SLOT_TX_B:

  case SLOT_RX_B:

    *which_codec = 1;

    break;

  default:

    fprintf (stderr, "usrp_prims:slot_to_codec: invalid slot = %d\n", slot);

    return false;

  }

  return true;

}

static bool

tx_slot_p (int slot)

{

  switch (slot){

  case SLOT_TX_A:

  case SLOT_TX_B:

    return true;

  default:

    return false;

  }

}

bool

usrp_write_aux_dac (struct usb_dev_handle *udh, int slot,

                    int which_dac, int value)

{

  int which_codec;

  if (!slot_to_codec (slot, &which_codec))

    return false;

  if (!(0 <= which_dac && which_dac < 4)){

    fprintf (stderr, "usrp_write_aux_dac: invalid dac = %d\n", which_dac);

    return false;

  }

  value &= 0x0fff;        // mask to 12-bits

  if (which_dac == 3){

    // dac 3 is really 12-bits.  Use value as is.

    bool r = true;

    r &= usrp_9862_write (udh, which_codec, 43, (value >> 4));       // most sig

    r &= usrp_9862_write (udh, which_codec, 42, (value & 0xf) << 4); // least sig

    return r;

  }

  else {

    // dac 0, 1, and 2 are really 8 bits.  

    value = value >> 4;                // shift value appropriately

    return usrp_9862_write (udh, which_codec, 36 + which_dac, value);

  }

}

bool

usrp_read_aux_adc (struct usb_dev_handle *udh, int slot,

                   int which_adc, int *value)

{

  *value = 0;

  int        which_codec;

  if (!slot_to_codec (slot, &which_codec))

    return false;

  if (!(0 <= which_codec && which_codec < 2)){

    fprintf (stderr, "usrp_read_aux_adc: invalid adc = %d\n", which_adc);

    return false;

  }

  unsigned char aux_adc_control =

    AUX_ADC_CTRL_REFSEL_A                // on chip reference

    | AUX_ADC_CTRL_REFSEL_B;                // on chip reference

  int        rd_reg = 26;        // base address of two regs to read for result

  // program the ADC mux bits

  if (tx_slot_p (slot))

    aux_adc_control |= AUX_ADC_CTRL_SELECT_A2 | AUX_ADC_CTRL_SELECT_B2;

  else {

    rd_reg += 2;

    aux_adc_control |= AUX_ADC_CTRL_SELECT_A1 | AUX_ADC_CTRL_SELECT_B1;

  }

  // I'm not sure if we can set the mux and issue a start conversion

  // in the same cycle, so let's do them one at a time.

  usrp_9862_write (udh, which_codec, 34, aux_adc_control);

  if (which_adc == 0)

    aux_adc_control |= AUX_ADC_CTRL_START_A;

  else {

    rd_reg += 4;

    aux_adc_control |= AUX_ADC_CTRL_START_B;

  }

  // start the conversion

  usrp_9862_write (udh, which_codec, 34, aux_adc_control);

  // read the 10-bit result back

  unsigned char v_lo = 0;

  unsigned char v_hi = 0;

  bool r = usrp_9862_read (udh, which_codec, rd_reg, &v_lo);

  r &= usrp_9862_read (udh, which_codec, rd_reg + 1, &v_hi);

  if (r)

    *value = ((v_hi << 2) | ((v_lo >> 6) & 0x3)) << 2;        // format as 12-bit

  return r;

}

// ----------------------------------------------------------------

static int slot_to_i2c_addr (int slot)

{

  switch (slot){

  case SLOT_TX_A:        return I2C_ADDR_TX_A;

  case SLOT_RX_A:        return I2C_ADDR_RX_A;

  case SLOT_TX_B:        return I2C_ADDR_TX_B;

  case SLOT_RX_B:        return I2C_ADDR_RX_B;

  default:                return -1;

  }

}

static void

set_chksum (unsigned char *buf)

{

  int sum = 0;

  unsigned int i;

  for (i = 0; i < DB_EEPROM_CLEN - 1; i++)

    sum += buf[i];

  buf[i] = -sum;

}

static usrp_dbeeprom_status_t

read_dboard_eeprom (struct usb_dev_handle *udh,

                    int slot_id, unsigned char *buf)

{

  int i2c_addr = slot_to_i2c_addr (slot_id);

  if (i2c_addr == -1)

    return UDBE_BAD_SLOT;

  if (!usrp_eeprom_read (udh, i2c_addr, 0, buf, DB_EEPROM_CLEN))

    return UDBE_NO_EEPROM;

  if (buf[DB_EEPROM_MAGIC] != DB_EEPROM_MAGIC_VALUE)

    return UDBE_INVALID_EEPROM;

  int sum = 0;

  for (unsigned int i = 0; i < DB_EEPROM_CLEN; i++)