/****************************************************************************
 * apps/graphics/ft80x/ft80x_coproc.c
 *
 *   Copyright (C) 2018 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <sys/ioctl.h>
#include <stdint.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>

#include <nuttx/lcd/ft80x.h>

#include "graphics/ft80x.h"
#include "ft80x.h"

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

#define HALF_SECOND  (500 * 1000)  /* 500 milliseconds (units = microseconds) */
#define FIVE_SECONDS (5 * 2)       /* 5 seconds (units = half seconds) */

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: ft80x_coproc_send
 *
 * Description:
 *   Send commands to the co-processor via the CMD RAM FIFO.  This function
 *   will not return until the command has been consumed by the co-processor.
 *
 *   This function is similar to ft80x_ramcmd_append() but does not depend
 *   on a display list.
 *
 *   NOTE:  This command is not appropriate use while a display is being
 *   formed.  It is will mess up the CMD RAM FIFO offsets managed by the
 *   display list logic.
 *
 * Input Parameters:
 *   fd     - The file descriptor of the FT80x device.  Opened by the caller
 *            with write access.
 *   cmds   - A list of 32-bit commands to be sent.
 *   ncmds  - The number of commands in the list.
 *
 * Returned Value:
 *   Zero (OK) on success.  A negated errno value on failure.
 *
 ****************************************************************************/

int ft80x_coproc_send(int fd, FAR const uint32_t *cmds, size_t ncmds)
{
  struct ft80x_relmem_s wrdesc;
  FAR const uint8_t *src;
  ssize_t remaining;
  size_t wrsize;
  uint16_t offset;
  uint16_t maxsize;
  int ret;

  /* Loop until all of the display list commands have been transferred to
   * FIFO.
   */

  src       = (FAR const uint8_t *)cmds;
  remaining = ncmds << 2;

  do
    {
      /* Write the number of bytes remaining to be transferred */

      wrsize = remaining;

      /* Get the amount of free space in the FIFO. */

      maxsize = 0;
      ret     = ft80x_ramcmd_freespace(fd, &offset, &maxsize);
      if (ret < 0)
        {
          ft80x_err("ERROR: ft80x_ramcmd_freespace() failed: %d\n", ret);
          return ret;
        }

      /* If the FIFO full? */

      if (maxsize == 0)
        {
          /* Yes.. wait a bit and try again */

          ft80x_warn("WARNING: FIFO is full: %d\n", ret);
          usleep(50 * 1000);
          continue;
        }

      /* Limit the write size to the size of the available FIFO memory */

      if (wrsize > (size_t)maxsize)
        {
          wrsize = (size_t)maxsize;
        }

      /* Perform the transfer */

      wrdesc.offset = offset;
      wrdesc.nbytes = wrsize;
      wrdesc.value  = (FAR void *)src;  /* Discards 'const' qualifier */

      ret = ioctl(fd, FT80X_IOC_PUTRAMCMD,
                  (unsigned long)((uintptr_t)&wrdesc));
      if (ret < 0)
        {
          int errcode = errno;
          ft80x_err("ERROR: ioctl() FT80X_IOC_PUTRAMCMD failed: %d\n",
                    errcode);
          return -errcode;
        }

      /* Update the command FIFO */

      ret = ft80x_putreg16(fd, FT80X_REG_CMD_WRITE, offset + wrsize);
      if (ret < 0)
        {
          ft80x_err("ERROR: ft80x_putreg16() failed: %d\n", ret);
          return ret;
        }

      /* Wait for the FIFO to empty */

      ret = ft80x_ramcmd_waitfifoempty(fd);
      if (ret < 0)
        {
          ft80x_err("ERROR: ft80x_ramcmd_waitfifoempty() failed: %d\n", ret);
          return ret;
        }

      /* Set up for the next time through the loop */

      remaining -= wrsize;
      src       += wrsize;
    }
  while (remaining > 0);

  return OK;
}

/****************************************************************************
 * Name: ft80x_coproc_waitlogo
 *
 * Description:
 *   Wait for the logo animation to complete.  The logo command causes the
 *   co-processor engine to play back a short animation of the FTDI logo.
 *   During logo playback the MCU should not access any FT800 resources.
 *   After 2.5 seconds have elapsed, the co-processor engine writes zero to
 *   REG_CMD_READ and REG_CMD_WRITE, and starts waiting for commands.  After
 *   this command is complete, the MCU shall write the next command to the
 *   starting address of RAM_CMD.
 *
 * Input Parameters:
 *   fd     - The file descriptor of the FT80x device.  Opened by the caller
 *            with write access.
 *
 * Returned Value:
 *   Zero (OK) on success.  A negated errno value on failure.
 *
 ****************************************************************************/

int ft80x_coproc_waitlogo(int fd)
{
  uint32_t regs[2];
  uint16_t head;
  uint16_t tail;
  int elapsed;
  int ret;

  /* Loop until both REG_CMD_READ and REG_CMD_WRITE are zero or until 5
   * seconds elapses.
   */

  for (elapsed = 0; elapsed < FIVE_SECONDS; elapsed++)
    {
      /* Read both the FT80X_REG_CMD_WRITE and FT80X_REG_CMD_READ registers. */

      ret = ft80x_getregs(fd, FT80X_REG_CMD_READ, 2, regs);
      if (ret < 0)
        {
          ft80x_err("ERROR: ft80x_getregs failed: %d\n", ret);
          return ret;
        }

      /* Check if both have been reset to zero. */

      head = regs[1] & FT80X_CMDFIFO_MASK;
      tail = regs[0] & FT80X_CMDFIFO_MASK;

      if (head == 0 && tail == 0)
        {
          /* The animation is done! */

          return OK;
        }

      /* Wait for a half of a second */

      (void)usleep(HALF_SECOND);
    }

  ft80x_err("ERROR:  Timed out!  Last head/tail = %u/%u\n", head, tail);
  return -ETIMEDOUT;
}