summaryrefslogtreecommitdiffstats
path: root/firmware/drivers/tuner/rda5802.c
blob: fe2b25f21379c99213b7866ecdf9fe8a316cfb08 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Tuner "middleware" for RDA5802 chip present in some Sansa Clip+ players
 *
 * Copyright (C) 2010 Bertrik Sikken
 * Copyright (C) 2008 Nils Wallménius (si4700 code that this was based on)
 *
 * 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/
#include "config.h"
#include <stdbool.h>
#include <string.h>
#include <stdlib.h>
#include "kernel.h"
#include "tuner.h" /* tuner abstraction interface */
#include "fmradio.h"
#include "fmradio_i2c.h" /* physical interface driver */

#define SEEK_THRESHOLD 0x16

#define I2C_ADR 0x20

/* define RSSI range */
#define RSSI_MIN 0
#define RSSI_MAX 70

/** Registers and bits **/
#define POWERCFG    0x2
#define CHANNEL     0x3
#define SYSCONFIG1  0x4
#define SYSCONFIG2  0x5
#define SYSCONFIG3  0x6

#define READCHAN    0xA
#define STATUSRSSI  0xB
#define IDENT       0xC


/* POWERCFG (0x2) */
#define POWERCFG_DMUTE      (0x1 << 14)
#define POWERCFG_MONO       (0x1 << 13)
#define POWERCFG_SOFT_RESET (0x1 <<  1)
#define POWERCFG_ENABLE     (0x1 <<  0)

/* CHANNEL (0x3) */
#define CHANNEL_CHAN        (0x3ff << 6)
    #define CHANNEL_CHANw(x) (((x) << 6) & CHANNEL_CHAN)
#define CHANNEL_TUNE        (0x1 << 4)
#define CHANNEL_BAND        (0x3 << 2)
    #define CHANNEL_BANDw(x)        (((x) << 2) & CHANNEL_BAND)
    #define CHANNEL_BANDr(x)        (((x) & CHANNEL_BAND) >> 2)
    #define CHANNEL_BAND_870_1080   (0x0) /* tenth-megahertz */
    #define CHANNEL_BAND_760_1080   (0x1)
    #define CHANNEL_BAND_760_900    (0x2)
    #define CHANNEL_BAND_650_760    (0x3)
#define CHANNEL_SPACE       (0x3 << 0)
    #define CHANNEL_SPACEw(x)  (((x) << 0) & CHANNEL_SPACE)
    #define CHANNEL_SPACEr(x)  (((x) & CHANNEL_SPACE) >> 0)
    #define CHANNEL_SPACE_100KHZ    (0x0)
    #define CHANNEL_SPACE_200KHZ    (0x1)
    #define CHANNEL_SPACE_50KHZ     (0x2)

/* SYSCONFIG1 (0x4) */
#define SYSCONFIG1_DE       (0x1 << 11)
    #define SYSCONFIG1_SMUTE (0x1 << 9)

/* SYSCONFIG2 (0x5) */
#define SYSCONFIG2_VOLUME   (0xF <<  0)

/* READCHAN (0xA) */
#define READCHAN_READCHAN   (0x3ff << 0)
    #define READCHAN_READCHANr(x) (((x) & READCHAN_READCHAN) >> 0)
#define READCHAN_STC        (0x1 << 14)
#define READCHAN_ST         (0x1 << 10)

/* STATUSRSSI (0xB) */
#define STATUSRSSI_RSSI     (0x7F << 9)
    #define STATUSRSSI_RSSIr(x) (((x) & STATUSRSSI_RSSI) >> 9)
#define STATUSRSSI_FM_TRUE  (0x1 << 8)

static const uint16_t initvals[16] = {
    0x0000, 0x0000, 0xC401, 0x1B90, 
    0x0400, 0x866F, 0x8000, 0x4712, 
    0x5EC6, 0x0000, 0x406E, 0x2D80, 
    0x5803, 0x5804, 0x5804, 0x5804
};

static bool tuner_present = false;
static uint16_t cache[16];

/* reads <len> registers from radio at offset 0x0A into cache */
static void rda5802_read(int len)
{
    int i;
    unsigned char buf[128];
    unsigned char *ptr = buf;
    uint16_t data;
    
    fmradio_i2c_read(I2C_ADR, buf, len * 2);
    for (i = 0; i < len; i++) {
        data = ptr[0] << 8 | ptr[1];
        cache[READCHAN + i] = data;
        ptr += 2;
    }
}

/* writes <len> registers from cache to radio at offset 0x02 */
static void rda5802_write(int len)
{
    int i;
    unsigned char buf[64];
    unsigned char *ptr = buf;
    uint16_t data;

    for (i = 0; i < len; i++) {
        data = cache[POWERCFG + i];
        *ptr++ = (data >> 8) & 0xFF;
        *ptr++ = data & 0xFF;
    }
    fmradio_i2c_write(I2C_ADR, buf, len * 2);
}

static uint16_t rda5802_read_reg(int reg)
{
    rda5802_read((reg - READCHAN) + 1);
    return cache[reg];
}

static void rda5802_write_reg(int reg, uint16_t value)
{
    cache[reg] = value;
}

static void rda5802_write_cache(void)
{
    rda5802_write(5);
}

static void rda5802_write_masked(int reg, uint16_t bits, uint16_t mask)
{
    rda5802_write_reg(reg, (cache[reg] & ~mask) | (bits & mask));
}

static void rda5802_write_clear(int reg, uint16_t mask)
{
    rda5802_write_reg(reg, cache[reg] & ~mask);
}

static void rda5802_write_set(int reg, uint16_t mask)
{
    rda5802_write_reg(reg, cache[reg] | mask);
}

static void rda5802_sleep(int snooze)
{
    if (snooze) {
        rda5802_write_clear(POWERCFG, POWERCFG_ENABLE);
    }
    else {
        rda5802_write_set(POWERCFG, POWERCFG_ENABLE);
    }
    rda5802_write_cache();
}

bool rda5802_detect(void)
{
    return ((rda5802_read_reg(IDENT) & 0xFF00) == 0x5800);
 }

void rda5802_init(void)
{
    if (rda5802_detect()) {
        tuner_present = true;

        // soft-reset
        rda5802_write_reg(POWERCFG, POWERCFG_SOFT_RESET);
        rda5802_write(1);
        sleep(HZ * 10 / 1000);

        // write initialisation values
        memcpy(cache, initvals, sizeof(cache));
        rda5802_write(14);
        sleep(HZ * 70 / 1000);
    }
}

static void rda5802_set_frequency(int freq)
{
    int i;
    uint16_t readchan;

    /* check BAND and spacings */
    int start = CHANNEL_BANDr(cache[CHANNEL]) & 1 ? 76000000 : 87000000;
    int chan = (freq - start) / 50000;

    for (i = 0; i < 5; i++) {
        /* tune and wait a bit */
        rda5802_write_masked(CHANNEL, CHANNEL_CHANw(chan) | CHANNEL_TUNE,
                                CHANNEL_CHAN | CHANNEL_TUNE);
        rda5802_write_cache();
        sleep(HZ * 70 / 1000);
        rda5802_write_clear(CHANNEL, CHANNEL_TUNE);
        rda5802_write_cache();
        
        /* check if tuning was successful */
        readchan = rda5802_read_reg(READCHAN);
        if (readchan & READCHAN_STC) {
            if (READCHAN_READCHANr(readchan) == chan) {
                break;
            }
        }
    }
}

static int rda5802_tuned(void)
{
    /* Primitive tuning check: sufficient level and AFC not railed */
    uint16_t status = rda5802_read_reg(STATUSRSSI);
    if (STATUSRSSI_RSSIr(status) >= SEEK_THRESHOLD &&
        (status & STATUSRSSI_FM_TRUE)) {
        return 1;
    }

    return 0;
}

static void rda5802_set_region(int region)
{
    const struct fm_region_data *rd = &fm_region_data[region];
    int band = (rd->freq_min == 76000000) ?
               CHANNEL_BAND_760_900 : CHANNEL_BAND_870_1080;
    int deemphasis = (rd->deemphasis == 50) ? SYSCONFIG1_DE : 0;

    uint16_t bandspacing = CHANNEL_BANDw(band) |
                           CHANNEL_SPACEw(CHANNEL_SPACE_50KHZ);
    rda5802_write_masked(SYSCONFIG1, deemphasis, SYSCONFIG1_DE);
    rda5802_write_masked(CHANNEL, bandspacing, CHANNEL_BAND | CHANNEL_SPACE);
    rda5802_write_cache();
}

static bool rda5802_st(void)
{
    return (rda5802_read_reg(READCHAN) & READCHAN_ST);
}

static int rda5802_rssi(void)
{
    uint16_t status = rda5802_read_reg(STATUSRSSI);
    return STATUSRSSI_RSSIr(status);
}

/* tuner abstraction layer: set something to the tuner */
int rda5802_set(int setting, int value)
{
    switch (setting) {
    case RADIO_SLEEP:
        if (value != 2) {
            rda5802_sleep(value);
        }
        break;

    case RADIO_FREQUENCY:
        rda5802_set_frequency(value);
        break;

    case RADIO_SCAN_FREQUENCY:
        rda5802_set_frequency(value);
        return rda5802_tuned();

    case RADIO_MUTE:
        rda5802_write_masked(POWERCFG, value ? 0 : POWERCFG_DMUTE,
                                POWERCFG_DMUTE);
        rda5802_write_masked(SYSCONFIG1, (3 << 9), (3 << 9));
        rda5802_write_set(SYSCONFIG2, SYSCONFIG2_VOLUME);
        rda5802_write_cache();
        break;

    case RADIO_REGION:
        rda5802_set_region(value);
        break;

    case RADIO_FORCE_MONO:
        rda5802_write_masked(POWERCFG, value ? POWERCFG_MONO : 0,
                            POWERCFG_MONO);
        rda5802_write_cache();
        break;

    default:
        return -1;
    }

    return 1;
}

/* tuner abstraction layer: read something from the tuner */
int rda5802_get(int setting)
{
    int val = -1; /* default for unsupported query */

    switch (setting) {
    case RADIO_PRESENT:
        val = tuner_present ? 1 : 0;
        break;

    case RADIO_TUNED:
        val = rda5802_tuned();
        break;

    case RADIO_STEREO:
        val = rda5802_st();
        break;

    case RADIO_RSSI:
        val = rda5802_rssi();
        break;

    case RADIO_RSSI_MIN:
        val = RSSI_MIN;
        break;

    case RADIO_RSSI_MAX:
        val = RSSI_MAX;
        break;
    }

    return val;
}

void rda5802_dbg_info(struct rda5802_dbg_info *nfo)
{
    rda5802_read(6);
    memcpy(nfo->regs, cache, sizeof (nfo->regs));
}