drivers/media/dvb/frontends/tda826x.c

   1   /*
   2      Driver for Philips tda8262/tda8263 DVBS Silicon tuners
   3
   4      (c) 2006 Andrew de Quincey
   5
   6      This program is free software; you can redistribute it and/or modify
   7      it under the terms of the GNU General Public License as published by
   8      the Free Software Foundation; either version 2 of the License, or
   9      (at your option) any later version.
  10
  11      This program is distributed in the hope that it will be useful,
  12      but WITHOUT ANY WARRANTY; without even the implied warranty of
  13      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14
  15      GNU General Public License for more details.
  16
  17      You should have received a copy of the GNU General Public License
  18      along with this program; if not, write to the Free Software
  19      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20
  21   */
  22
  23 #include <linux/module.h>
  24 #include <linux/dvb/frontend.h>
  25 #include <asm/types.h>
  26
  27 #include "tda826x.h"
  28
  29 static int debug;
  30 #define dprintk(args...) \
  31         do { \
  32                 if (debug) printk(KERN_DEBUG "tda826x: " args); \
  33         } while (0)
  34
  35 struct tda826x_priv {
  36         /* i2c details */
  37         int i2c_address;
  38         struct i2c_adapter *i2c;
  39         u8 has_loopthrough:1;
  40         u32 frequency;
  41 };
  42
  43 static int tda826x_release(struct dvb_frontend *fe)
  44 {
  45         kfree(fe->tuner_priv);
  46         fe->tuner_priv = NULL;
  47         return 0;
  48 }
  49
  50 static int tda826x_sleep(struct dvb_frontend *fe)
  51 {
  52         struct tda826x_priv *priv = fe->tuner_priv;
  53         int ret;
  54         u8 buf [] = { 0x00, 0x8d };
  55         struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 2 };
  56
  57         dprintk("%s:\n", __func__);
  58
  59         if (!priv->has_loopthrough)
  60                 buf[1] = 0xad;
  61
  62         if (fe->ops.i2c_gate_ctrl)
  63                 fe->ops.i2c_gate_ctrl(fe, 1);
  64         if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
  65                 dprintk("%s: i2c error\n", __func__);
  66         }
  67         if (fe->ops.i2c_gate_ctrl)
  68                 fe->ops.i2c_gate_ctrl(fe, 0);
  69
  70         return (ret == 1) ? 0 : ret;
  71 }
  72
  73 static int tda826x_set_params(struct dvb_frontend *fe, struct dvb_frontend_parameters *params)
  74 {
  75         struct tda826x_priv *priv = fe->tuner_priv;
  76         int ret;
  77         u32 div;
  78         u32 ksyms;
  79         u32 bandwidth;
  80         u8 buf [11];
  81         struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 11 };
  82
  83         dprintk("%s:\n", __func__);
  84
  85         div = (params->frequency + (1000-1)) / 1000;
  86
  87         /* BW = ((1 + RO) * SR/2 + 5) * 1.3      [SR in MSPS, BW in MHz] */
  88         /* with R0 = 0.35 and some transformations: */
  89         ksyms = params->u.qpsk.symbol_rate / 1000;
  90         bandwidth = (878 * ksyms + 6500000) / 1000000 + 1;
  91         if (bandwidth < 5)
  92                 bandwidth = 5;
  93         else if (bandwidth > 36)
  94                 bandwidth = 36;
  95
  96         buf[0] = 0x00; // subaddress
  97         buf[1] = 0x09; // powerdown RSSI + the magic value 1
  98         if (!priv->has_loopthrough)
  99                 buf[1] |= 0x20; // power down loopthrough if not needed
 100         buf[2] = (1<<5) | 0x0b; // 1Mhz + 0.45 VCO
 101         buf[3] = div >> 7;
 102         buf[4] = div << 1;
 103         buf[5] = ((bandwidth - 5) << 3) | 7; /* baseband cut-off */
 104         buf[6] = 0xfe; // baseband gain 9 db + no RF attenuation
 105         buf[7] = 0x83; // charge pumps at high, tests off
 106         buf[8] = 0x80; // recommended value 4 for AMPVCO + disable ports.
 107         buf[9] = 0x1a; // normal caltime + recommended values for SELTH + SELVTL
 108         buf[10] = 0xd4; // recommended value 13 for BBIAS + unknown bit set on
 109
 110         if (fe->ops.i2c_gate_ctrl)
 111                 fe->ops.i2c_gate_ctrl(fe, 1);
 112         if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
 113                 dprintk("%s: i2c error\n", __func__);
 114         }
 115         if (fe->ops.i2c_gate_ctrl)
 116                 fe->ops.i2c_gate_ctrl(fe, 0);
 117
 118         priv->frequency = div * 1000;
 119
 120         return (ret == 1) ? 0 : ret;
 121 }
 122
 123 static int tda826x_get_frequency(struct dvb_frontend *fe, u32 *frequency)
 124 {
 125         struct tda826x_priv *priv = fe->tuner_priv;
 126         *frequency = priv->frequency;
 127         return 0;
 128 }
 129
 130 static struct dvb_tuner_ops tda826x_tuner_ops = {
 131         .info = {
 132                 .name = "Philips TDA826X",
 133                 .frequency_min = 950000,
 134                 .frequency_max = 2175000
 135         },
 136         .release = tda826x_release,
 137         .sleep = tda826x_sleep,
 138         .set_params = tda826x_set_params,
 139         .get_frequency = tda826x_get_frequency,
 140 };
 141
 142 struct dvb_frontend *tda826x_attach(struct dvb_frontend *fe, int addr, struct i2c_adapter *i2c, int has_loopthrough)
 143 {
 144         struct tda826x_priv *priv = NULL;
 145         u8 b1 [] = { 0, 0 };
 146         struct i2c_msg msg[2] = {
 147                 { .addr = addr, .flags = 0,        .buf = NULL, .len = 0 },
 148                 { .addr = addr, .flags = I2C_M_RD, .buf = b1, .len = 2 }
 149         };
 150         int ret;
 151
 152         dprintk("%s:\n", __func__);
 153
 154         if (fe->ops.i2c_gate_ctrl)
 155                 fe->ops.i2c_gate_ctrl(fe, 1);
 156         ret = i2c_transfer (i2c, msg, 2);
 157         if (fe->ops.i2c_gate_ctrl)
 158                 fe->ops.i2c_gate_ctrl(fe, 0);
 159
 160         if (ret != 2)
 161                 return NULL;
 162         if (!(b1[1] & 0x80))
 163                 return NULL;
 164
 165         priv = kzalloc(sizeof(struct tda826x_priv), GFP_KERNEL);
 166         if (priv == NULL)
 167                 return NULL;
 168
 169         priv->i2c_address = addr;
 170         priv->i2c = i2c;
 171         priv->has_loopthrough = has_loopthrough;
 172
 173         memcpy(&fe->ops.tuner_ops, &tda826x_tuner_ops, sizeof(struct dvb_tuner_ops));
 174
 175         fe->tuner_priv = priv;
 176
 177         return fe;
 178 }
 179 EXPORT_SYMBOL(tda826x_attach);
 180
 181 module_param(debug, int, 0644);
 182 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 183
 184 MODULE_DESCRIPTION("DVB TDA826x driver");
 185 MODULE_AUTHOR("Andrew de Quincey");
 186 MODULE_LICENSE("GPL");