/* $NetBSD: tea5757.c,v 1.5 2005/12/11 12:21:28 christos Exp $ */
/*      $OpenBSD: tea5757.c,v 1.3 2002/01/07 18:32:19 mickey Exp $      */

/*
* Copyright (c) 2001 Vladimir Popov <[email protected]>
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/

/* Implementation of most common TEA5757 routines */

/*
* Philips TEA5757H Self Tuned Radio
*         http://www.semiconductors.philips.com/pip/TEA5757H
*
* The TEA5757; TEA5759 is a 44-pin integrated AM/FM stereo radio circuit.
* The radio part is based on the TEA5712.
*
* The TEA5757 is used in FM-standards in which the local oscillator
* frequency is above the radio frequency (e.g. European and American
* standards). The TEA5759 is the version in which the oscillator frequency
* is below the radio frequency (e.g. Japanese standard).
*
* The TEA5757; TEA5759 radio has a bus which consists of three wires:
* BUS-CLOCK: software driven clock input
* DATA: data input/output
* WRITE-ENABLE: write/read input
*
* The TEA5757; TEA5759 has a 25-bit shift register.
*
* The chips are used in Radiotrack II, Guillemot Maxi Radio FM 2000,
* Gemtek PCI cards and most Mediaforte FM tuners and sound cards with
* integrated FM tuners.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: tea5757.c,v 1.5 2005/12/11 12:21:28 christos Exp $");

#include <sys/param.h>
#include <sys/radioio.h>

#include <dev/ic/tea5757.h>

/*
* Convert frequency to hardware representation
*/
u_int32_t
tea5757_encode_freq(u_int32_t freq, int tea5759)
{
       if (tea5759)
               freq -= IF_FREQ;
       else
               freq += IF_FREQ;

       /*
        * NO FLOATING POINT!
        */
       freq *= 10;
       freq /= 125;

       return freq & TEA5757_FREQ;
}

/*
* Convert frequency from hardware representation
*/
u_int32_t
tea5757_decode_freq(u_int32_t freq, int tea5759)
{
       freq &= TEA5757_FREQ;
       freq *= 125; /* 12.5 kHz */
       freq /= 10;

       if (tea5759)
               freq += IF_FREQ;
       else
               freq -= IF_FREQ;

       return freq;
}

/*
* Hardware search
*/
void
tea5757_search(struct tea5757_t *tea, u_int32_t stereo, u_int32_t lock, int dir)
{
       u_int32_t reg;
       u_int co = 0;

       reg = stereo | lock | TEA5757_SEARCH_START;
       reg |= dir ? TEA5757_SEARCH_UP : TEA5757_SEARCH_DOWN;
       tea5757_hardware_write(tea, reg);

       DELAY(TEA5757_ACQUISITION_DELAY);

       do {
               DELAY(TEA5757_WAIT_DELAY);
               reg = tea->read(tea->iot, tea->ioh, tea->offset);
       } while ((reg & TEA5757_FREQ) == 0 && ++co < 200);
}

void
tea5757_hardware_write(struct tea5757_t *tea, u_int32_t data)
{
       int i = TEA5757_REGISTER_LENGTH;

       tea->init(tea->iot, tea->ioh, tea->offset, 0);

       while (i--)
               if (data & (1 << i))
                       tea->write_bit(tea->iot, tea->ioh, tea->offset, 1);
               else
                       tea->write_bit(tea->iot, tea->ioh, tea->offset, 0);

       tea->rset(tea->iot, tea->ioh, tea->offset, 0);
}

u_int32_t
tea5757_set_freq(struct tea5757_t *tea, u_int32_t stereo, u_int32_t lock, u_int32_t freq)
{
       u_int32_t data = 0ul;

       if (freq < MIN_FM_FREQ)
               freq = MIN_FM_FREQ;
       if (freq > MAX_FM_FREQ)
               freq = MAX_FM_FREQ;

       data |= tea5757_encode_freq(freq, tea->flags & TEA5757_TEA5759);
       data |= stereo | lock | TEA5757_SEARCH_END;
       tea5757_hardware_write(tea, data);

       return freq;
}

u_int32_t
tea5757_encode_lock(u_int8_t lock)
{
       if (lock < 8)
               return TEA5757_S005;
       if (lock < 15)
               return TEA5757_S010;
       if (lock < 51)
               return TEA5757_S030;
       return TEA5757_S150;
}

u_int8_t
tea5757_decode_lock(u_int32_t lock)
{
       switch (lock) {
       case TEA5757_S005:
               return 5;
       case TEA5757_S010:
               return 10;
               break;
       case TEA5757_S030:
               return 30;
       case TEA5757_S150:
       default:
               return 150;
       }
}