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tea5757.c revision 1.2 
      1 /* $NetBSD: tea5757.c,v 1.2 2002/09/03 18:53:40 augustss Exp $ */
      2 /*	$OpenBSD: tea5757.c,v 1.3 2002/01/07 18:32:19 mickey Exp $	*/
      3 
      4 /*
      5  * Copyright (c) 2001 Vladimir Popov <jumbo (at) narod.ru>
      6  * All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  *
     17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
     23  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
     24  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
     25  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
     26  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 /* Implementation of most common TEA5757 routines */
     30 
     31 /*
     32  * Philips TEA5757H Self Tuned Radio
     33  *         http://www.semiconductors.philips.com/pip/TEA5757H
     34  *
     35  * The TEA5757; TEA5759 is a 44-pin integrated AM/FM stereo radio circuit.
     36  * The radio part is based on the TEA5712.
     37  *
     38  * The TEA5757 is used in FM-standards in which the local oscillator
     39  * frequency is above the radio frequency (e.g. European and American
     40  * standards). The TEA5759 is the version in which the oscillator frequency
     41  * is below the radio frequency (e.g. Japanese standard).
     42  *
     43  * The TEA5757; TEA5759 radio has a bus which consists of three wires:
     44  * BUS-CLOCK: software driven clock input
     45  * DATA: data input/output
     46  * WRITE-ENABLE: write/read input
     47  *
     48  * The TEA5757; TEA5759 has a 25-bit shift register.
     49  *
     50  * The chips are used in Radiotrack II, Guillemot Maxi Radio FM 2000,
     51  * Gemtek PCI cards and most Mediaforte FM tuners and sound cards with
     52  * integrated FM tuners.
     53  */
     54 
     55 #include <sys/param.h>
     56 #include <sys/radioio.h>
     57 
     58 #include <dev/ic/tea5757.h>
     59 
     60 /*
     61  * Convert frequency to hardware representation
     62  */
     63 u_int32_t
     64 tea5757_encode_freq(u_int32_t freq, int tea5759)
     65 {
     66 	if (tea5759)
     67 		freq -= IF_FREQ;
     68 	else
     69 		freq += IF_FREQ;
     70 
     71 	/*
     72 	 * NO FLOATING POINT!
     73 	 */
     74 	freq *= 10;
     75 	freq /= 125;
     76 
     77 	return freq & TEA5757_FREQ;
     78 }
     79 
     80 /*
     81  * Convert frequency from hardware representation
     82  */
     83 u_int32_t
     84 tea5757_decode_freq(u_int32_t freq, int tea5759)
     85 {
     86 	freq &= TEA5757_FREQ;
     87 	freq *= 125; /* 12.5 kHz */
     88 	freq /= 10;
     89 
     90 	if (tea5759)
     91 		freq += IF_FREQ;
     92 	else
     93 		freq -= IF_FREQ;
     94 
     95 	return freq;
     96 }
     97 
     98 /*
     99  * Hardware search
    100  */
    101 void
    102 tea5757_search(struct tea5757_t *tea, u_int32_t stereo, u_int32_t lock, int dir)
    103 {
    104 	u_int32_t reg;
    105 	u_int co = 0;
    106 
    107 	reg = stereo | lock | TEA5757_SEARCH_START;
    108 	reg |= dir ? TEA5757_SEARCH_UP : TEA5757_SEARCH_DOWN;
    109 	tea5757_hardware_write(tea, reg);
    110 
    111 	DELAY(TEA5757_ACQUISITION_DELAY);
    112 
    113 	do {
    114 		DELAY(TEA5757_WAIT_DELAY);
    115 		reg = tea->read(tea->iot, tea->ioh, tea->offset);
    116 	} while ((reg & TEA5757_FREQ) == 0 && ++co < 200);
    117 }
    118 
    119 void
    120 tea5757_hardware_write(struct tea5757_t *tea, u_int32_t data)
    121 {
    122 	int i = TEA5757_REGISTER_LENGTH;
    123 
    124 	tea->init(tea->iot, tea->ioh, tea->offset, 0);
    125 
    126 	while (i--)
    127 		if (data & (1 << i))
    128 			tea->write_bit(tea->iot, tea->ioh, tea->offset, 1);
    129 		else
    130 			tea->write_bit(tea->iot, tea->ioh, tea->offset, 0);
    131 
    132 	tea->rset(tea->iot, tea->ioh, tea->offset, 0);
    133 }
    134 
    135 u_int32_t
    136 tea5757_set_freq(struct tea5757_t *tea, u_int32_t stereo, u_int32_t lock, u_int32_t freq)
    137 {
    138 	u_int32_t data = 0ul;
    139 
    140 	if (freq < MIN_FM_FREQ)
    141 		freq = MIN_FM_FREQ;
    142 	if (freq > MAX_FM_FREQ)
    143 		freq = MAX_FM_FREQ;
    144 
    145 	data |= tea5757_encode_freq(freq, tea->flags & TEA5757_TEA5759);
    146 	data |= stereo | lock | TEA5757_SEARCH_END;
    147 	tea5757_hardware_write(tea, data);
    148 
    149 	return freq;
    150 }
    151 
    152 u_int32_t
    153 tea5757_encode_lock(u_int8_t lock)
    154 {
    155 	u_int32_t ret;
    156 
    157 	if (lock < 8)
    158 		ret = TEA5757_S005;
    159 	else if (lock > 7 && lock < 15)
    160 		ret = TEA5757_S010;
    161 	else if (lock > 14 && lock < 51)
    162 		ret = TEA5757_S030;
    163 	else if (lock > 50)
    164 		ret = TEA5757_S150;
    165 
    166 	return ret;
    167 }
    168 
    169 u_int8_t
    170 tea5757_decode_lock(u_int32_t lock)
    171 {
    172 	u_int8_t ret = 150;
    173 
    174 	switch (lock) {
    175 	case TEA5757_S005:
    176 		ret = 5;
    177 		break;
    178 	case TEA5757_S010:
    179 		ret = 10;
    180 		break;
    181 	case TEA5757_S030:
    182 		ret = 30;
    183 		break;
    184 	case TEA5757_S150:
    185 		ret = 150;
    186 		break;
    187 	}
    188 
    189 	return ret;
    190 }
    191