drivers/media/dvb-frontends/tda8261.c

   1 /*
   2         TDA8261 8PSK/QPSK tuner driver
   3         Copyright (C) Manu Abraham (abraham.manu@gmail.com)
   4
   5         This program is free software; you can redistribute it and/or modify
   6         it under the terms of the GNU General Public License as published by
   7         the Free Software Foundation; either version 2 of the License, or
   8         (at your option) any later version.
   9
  10         This program is distributed in the hope that it will be useful,
  11         but WITHOUT ANY WARRANTY; without even the implied warranty of
  12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13         GNU General Public License for more details.
  14
  15         You should have received a copy of the GNU General Public License
  16         along with this program; if not, write to the Free Software
  17         Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18 */
  19
  20
  21 #include <linux/init.h>
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/slab.h>
  25
  26 #include "dvb_frontend.h"
  27 #include "tda8261.h"
  28
  29 struct tda8261_state {
  30         struct dvb_frontend             *fe;
  31         struct i2c_adapter              *i2c;
  32         const struct tda8261_config     *config;
  33
  34         /* state cache */
  35         u32 frequency;
  36         u32 bandwidth;
  37 };
  38
  39 static int tda8261_read(struct tda8261_state *state, u8 *buf)
  40 {
  41         const struct tda8261_config *config = state->config;
  42         int err = 0;
  43         struct i2c_msg msg = { .addr    = config->addr, .flags = I2C_M_RD,.buf = buf,  .len = 1 };
  44
  45         if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1)
  46                 pr_err("%s: read error, err=%d\n", __func__, err);
  47
  48         return err;
  49 }
  50
  51 static int tda8261_write(struct tda8261_state *state, u8 *buf)
  52 {
  53         const struct tda8261_config *config = state->config;
  54         int err = 0;
  55         struct i2c_msg msg = { .addr = config->addr, .flags = 0, .buf = buf, .len = 4 };
  56
  57         if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1)
  58                 pr_err("%s: write error, err=%d\n", __func__, err);
  59
  60         return err;
  61 }
  62
  63 static int tda8261_get_status(struct dvb_frontend *fe, u32 *status)
  64 {
  65         struct tda8261_state *state = fe->tuner_priv;
  66         u8 result = 0;
  67         int err = 0;
  68
  69         *status = 0;
  70
  71         if ((err = tda8261_read(state, &result)) < 0) {
  72                 pr_err("%s: I/O Error\n", __func__);
  73                 return err;
  74         }
  75         if ((result >> 6) & 0x01) {
  76                 pr_debug("%s: Tuner Phase Locked\n", __func__);
  77                 *status = 1;
  78         }
  79
  80         return err;
  81 }
  82
  83 static const u32 div_tab[] = { 2000, 1000,  500,  250,  125 }; /* kHz */
  84 static const u8  ref_div[] = { 0x00, 0x01, 0x02, 0x05, 0x07 };
  85
  86 static int tda8261_get_state(struct dvb_frontend *fe,
  87                              enum tuner_param param,
  88                              struct tuner_state *tstate)
  89 {
  90         struct tda8261_state *state = fe->tuner_priv;
  91         int err = 0;
  92
  93         switch (param) {
  94         case DVBFE_TUNER_FREQUENCY:
  95                 tstate->frequency = state->frequency;
  96                 break;
  97         case DVBFE_TUNER_BANDWIDTH:
  98                 tstate->bandwidth = 40000000; /* FIXME! need to calculate Bandwidth */
  99                 break;
 100         default:
 101                 pr_err("%s: Unknown parameter (param=%d)\n", __func__, param);
 102                 err = -EINVAL;
 103                 break;
 104         }
 105
 106         return err;
 107 }
 108
 109 static int tda8261_set_state(struct dvb_frontend *fe,
 110                              enum tuner_param param,
 111                              struct tuner_state *tstate)
 112 {
 113         struct tda8261_state *state = fe->tuner_priv;
 114         const struct tda8261_config *config = state->config;
 115         u32 frequency, N, status = 0;
 116         u8 buf[4];
 117         int err = 0;
 118
 119         if (param & DVBFE_TUNER_FREQUENCY) {
 120                 /**
 121                  * N = Max VCO Frequency / Channel Spacing
 122                  * Max VCO Frequency = VCO frequency + (channel spacing - 1)
 123                  * (to account for half channel spacing on either side)
 124                  */
 125                 frequency = tstate->frequency;
 126                 if ((frequency < 950000) || (frequency > 2150000)) {
 127                         pr_warn("%s: Frequency beyond limits, frequency=%d\n", __func__, frequency);
 128                         return -EINVAL;
 129                 }
 130                 N = (frequency + (div_tab[config->step_size] - 1)) / div_tab[config->step_size];
 131                 pr_debug("%s: Step size=%d, Divider=%d, PG=0x%02x (%d)\n",
 132                         __func__, config->step_size, div_tab[config->step_size], N, N);
 133
 134                 buf[0] = (N >> 8) & 0xff;
 135                 buf[1] = N & 0xff;
 136                 buf[2] = (0x01 << 7) | ((ref_div[config->step_size] & 0x07) << 1);
 137
 138                 if (frequency < 1450000)
 139                         buf[3] = 0x00;
 140                 else if (frequency < 2000000)
 141                         buf[3] = 0x40;
 142                 else if (frequency < 2150000)
 143                         buf[3] = 0x80;
 144
 145                 /* Set params */
 146                 if ((err = tda8261_write(state, buf)) < 0) {
 147                         pr_err("%s: I/O Error\n", __func__);
 148                         return err;
 149                 }
 150                 /* sleep for some time */
 151                 pr_debug("%s: Waiting to Phase LOCK\n", __func__);
 152                 msleep(20);
 153                 /* check status */
 154                 if ((err = tda8261_get_status(fe, &status)) < 0) {
 155                         pr_err("%s: I/O Error\n", __func__);
 156                         return err;
 157                 }
 158                 if (status == 1) {
 159                         pr_debug("%s: Tuner Phase locked: status=%d\n", __func__, status);
 160                         state->frequency = frequency; /* cache successful state */
 161                 } else {
 162                         pr_debug("%s: No Phase lock: status=%d\n", __func__, status);
 163                 }
 164         } else {
 165                 pr_err("%s: Unknown parameter (param=%d)\n", __func__, param);
 166                 return -EINVAL;
 167         }
 168
 169         return 0;
 170 }
 171
 172 static int tda8261_release(struct dvb_frontend *fe)
 173 {
 174         struct tda8261_state *state = fe->tuner_priv;
 175
 176         fe->tuner_priv = NULL;
 177         kfree(state);
 178         return 0;
 179 }
 180
 181 static struct dvb_tuner_ops tda8261_ops = {
 182
 183         .info = {
 184                 .name           = "TDA8261",
 185 //              .tuner_name     = NULL,
 186                 .frequency_min  =  950000,
 187                 .frequency_max  = 2150000,
 188                 .frequency_step = 0
 189         },
 190
 191         .set_state      = tda8261_set_state,
 192         .get_state      = tda8261_get_state,
 193         .get_status     = tda8261_get_status,
 194         .release        = tda8261_release
 195 };
 196
 197 struct dvb_frontend *tda8261_attach(struct dvb_frontend *fe,
 198                                     const struct tda8261_config *config,
 199                                     struct i2c_adapter *i2c)
 200 {
 201         struct tda8261_state *state = NULL;
 202
 203         if ((state = kzalloc(sizeof (struct tda8261_state), GFP_KERNEL)) == NULL)
 204                 goto exit;
 205
 206         state->config           = config;
 207         state->i2c              = i2c;
 208         state->fe               = fe;
 209         fe->tuner_priv          = state;
 210         fe->ops.tuner_ops       = tda8261_ops;
 211
 212         fe->ops.tuner_ops.info.frequency_step = div_tab[config->step_size];
 213 //      fe->ops.tuner_ops.tuner_name     = &config->buf;
 214
 215 //      printk("%s: Attaching %s TDA8261 8PSK/QPSK tuner\n",
 216 //              __func__, fe->ops.tuner_ops.tuner_name);
 217         pr_info("%s: Attaching TDA8261 8PSK/QPSK tuner\n", __func__);
 218
 219         return fe;
 220
 221 exit:
 222         kfree(state);
 223         return NULL;
 224 }
 225
 226 EXPORT_SYMBOL(tda8261_attach);
 227
 228 MODULE_AUTHOR("Manu Abraham");
 229 MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner");
 230 MODULE_LICENSE("GPL");