/*
  fx.c
  David Rowe 21 Sep 2006
 
  Functions supporting the 4fx card for Linux device drivers on the
  Blackfin that support interfacing the Blackfin.

  These functions are in a separate file from the target wcfxs driver
  so they can be re-used with different drivers, for example unit
  test software. 
 
  Include this file after including bfsi.c

  See also unittest spi/tspi_4fx_det.c

  TODO: work out a way to make this a seperately compiled module,
  include files are messy, perhaps make this a stand-alone module, wor
  work out how to link it with other .ko's
*/

/*
  Copyright (C) 2006 David Rowe
 
  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., 675 Mass Ave, Cambridge, MA 02139, USA. 
*/

#define FX_MAX_DBS     4  // max number of 4fx daughter boards
#define FX_MAX_PORTS   8  // max number of ports in system
#define FX_LED_OFF     0
#define FX_LED_RED     1
#define FX_LED_GREEN   2

static int led[FX_MAX_DBS];

/*

  From hardware-x.y tar ball, cpld dir, README.txt:

  D1 D0 | LED1
  ------|---
  0   0 | off
  0   1 | red
  1   0 | green
  1   1 | off

  An similarly for the other LEDs:

  D[3:2] LED2
  D[5:4] LED3
  D[7:6] LED4

 */

void fx_set_led(int port, int state) {
  int card;

  if (port > 4) {
    bfsi_spi_write_8_bits(SPI_NCSB, 0x45);
    port -= 4;
    card = 1;
  }
  else {
    bfsi_spi_write_8_bits(SPI_NCSB, 0x05);
    card = 0;
  }

  led[card] &= ~(0x3 << ((port-1)*2));
  led[card] |= state << ((port-1)*2);

  bfsi_spi_write_8_bits(SPI_NCSA, led[card]); 
}

/*----------------- PORT READ FUNCTIONS --------------------------*/

// read register 0x2 of 3050 FXO

char fx_read_fxo(int port) {
    u8  reg;

    if (port > 4)
      port += 0x40 - 4;
    bfsi_spi_write_8_bits(SPI_NCSB, port); 
    bfsi_spi_write_8_bits(SPI_NCSA, 0x60);
    bfsi_spi_write_8_bits(SPI_NCSA, 0x02);
    reg =  bfsi_spi_read_8_bits(SPI_NCSA);

    return reg;
}

// read register 0x0 of 3210 FXS

char fx_read_fxs(int port) {
    u8  reg;

    if (port > 4)
      port += 0x40 - 4;
    bfsi_spi_write_8_bits(SPI_NCSB, port); 
    bfsi_spi_write_8_bits(SPI_NCSA, 0x80);
    reg =  bfsi_spi_read_8_bits(SPI_NCSA);
    return reg;
}

void fx_auto_detect(char port_type[], int bit_reset) {
  int i;
  u8  reg;

  for(i=0; i<FX_MAX_PORTS; i++) {
    port_type[i] = '-';

    bfsi_reset(bit_reset);
    reg = fx_read_fxo(i+1);
    if (reg == 0x3) {
      port_type[i] = 'O';
      fx_set_led(i+1, FX_LED_RED);
    }
    else {
      bfsi_reset(bit_reset);
      reg = fx_read_fxs(i+1);
      if (reg == 0x5) {
	port_type[i] = 'S';
        fx_set_led(i+1, FX_LED_GREEN);
      }
    }
  }
}