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/slab.h>
  24 #include <linux/module.h>
  25 #include <linux/dvb/frontend.h>
  26 #include <asm/types.h>
  27
  28 #include "tda826x.h"
  29
  30 static int debug;
  31 #define dprintk(args...) \
  32         do { \
  33                 if (debug) printk(KERN_DEBUG "tda826x: " args); \
  34         } while (0)
  35
  36 struct tda826x_priv {
  37         /* i2c details */
  38         int i2c_address;
  39         struct i2c_adapter *i2c;
  40         u8 has_loopthrough:1;
  41         u32 frequency;
  42 };
  43
  44 static int tda826x_release(struct dvb_frontend *fe)
  45 {
  46         kfree(fe->tuner_priv);
  47         fe->tuner_priv = NULL;
  48         return 0;
  49 }
  50
  51 static int tda826x_sleep(struct dvb_frontend *fe)
  52 {
  53         struct tda826x_priv *priv = fe->tuner_priv;
  54         int ret;
  55         u8 buf [] = { 0x00, 0x8d };
  56         struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 2 };
  57
  58         dprintk("%s:\n", __func__);
  59
  60         if (!priv->has_loopthrough)
  61                 buf[1] = 0xad;
  62
  63         if (fe->ops.i2c_gate_ctrl)
  64                 fe->ops.i2c_gate_ctrl(fe, 1);
  65         if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
  66                 dprintk("%s: i2c error\n", __func__);
  67         }
  68         if (fe->ops.i2c_gate_ctrl)
  69                 fe->ops.i2c_gate_ctrl(fe, 0);
  70
  71         return (ret == 1) ? 0 : ret;
  72 }
  73
  74 static int tda826x_set_params(struct dvb_frontend *fe, struct dvb_frontend_parameters *params)
  75 {
  76         struct tda826x_priv *priv = fe->tuner_priv;
  77         int ret;
  78         u32 div;
  79         u32 ksyms;
  80         u32 bandwidth;
  81         u8 buf [11];
  82         struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 11 };
  83
  84         dprintk("%s:\n", __func__);
  85
  86         div = (params->frequency + (1000-1)) / 1000;
  87
  88         /* BW = ((1 + RO) * SR/2 + 5) * 1.3      [SR in MSPS, BW in MHz] */
  89         /* with R0 = 0.35 and some transformations: */
  90         ksyms = params->u.qpsk.symbol_rate / 1000;
  91         bandwidth = (878 * ksyms + 6500000) / 1000000 + 1;
  92         if (bandwidth < 5)
  93                 bandwidth = 5;
  94         else if (bandwidth > 36)
  95                 bandwidth = 36;
  96
  97         buf[0] = 0x00; // subaddress
  98         buf[1] = 0x09; // powerdown RSSI + the magic value 1
  99         if (!priv->has_loopthrough)
 100                 buf[1] |= 0x20; // power down loopthrough if not needed
 101         buf[2] = (1<<5) | 0x0b; // 1Mhz + 0.45 VCO
 102         buf[3] = div >> 7;
 103         buf[4] = div << 1;
 104         buf[5] = ((bandwidth - 5) << 3) | 7; /* baseband cut-off */
 105         buf[6] = 0xfe; // baseband gain 9 db + no RF attenuation
 106         buf[7] = 0x83; // charge pumps at high, tests off
 107         buf[8] = 0x80; // recommended value 4 for AMPVCO + disable ports.
 108         buf[9] = 0x1a; // normal caltime + recommended values for SELTH + SELVTL
 109         buf[10] = 0xd4; // recommended value 13 for BBIAS + unknown bit set on
 110
 111         if (fe->ops.i2c_gate_ctrl)
 112                 fe->ops.i2c_gate_ctrl(fe, 1);
 113         if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
 114                 dprintk("%s: i2c error\n", __func__);
 115         }
 116         if (fe->ops.i2c_gate_ctrl)
 117                 fe->ops.i2c_gate_ctrl(fe, 0);
 118
 119         priv->frequency = div * 1000;
 120
 121         return (ret == 1) ? 0 : ret;
 122 }
 123
 124 static int tda826x_get_frequency(struct dvb_frontend *fe, u32 *frequency)
 125 {
 126         struct tda826x_priv *priv = fe->tuner_priv;
 127         *frequency = priv->frequency;
 128         return 0;
 129 }
 130
 131 static struct dvb_tuner_ops tda826x_tuner_ops = {
 132         .info = {
 133                 .name = "Philips TDA826X",
 134                 .frequency_min = 950000,
 135                 .frequency_max = 2175000
 136         },
 137         .release = tda826x_release,
 138         .sleep = tda826x_sleep,
 139         .set_params = tda826x_set_params,
 140         .get_frequency = tda826x_get_frequency,
 141 };
 142
 143 struct dvb_frontend *tda826x_attach(struct dvb_frontend *fe, int addr, struct i2c_adapter *i2c, int has_loopthrough)
 144 {
 145         struct tda826x_priv *priv = NULL;
 146         u8 b1 [] = { 0, 0 };
 147         struct i2c_msg msg[2] = {
 148                 { .addr = addr, .flags = 0,        .buf = NULL, .len = 0 },
 149                 { .addr = addr, .flags = I2C_M_RD, .buf = b1, .len = 2 }
 150         };
 151         int ret;
 152
 153         dprintk("%s:\n", __func__);
 154
 155         if (fe->ops.i2c_gate_ctrl)
 156                 fe->ops.i2c_gate_ctrl(fe, 1);
 157         ret = i2c_transfer (i2c, msg, 2);
 158         if (fe->ops.i2c_gate_ctrl)
 159                 fe->ops.i2c_gate_ctrl(fe, 0);
 160
 161         if (ret != 2)
 162                 return NULL;
 163         if (!(b1[1] & 0x80))
 164                 return NULL;
 165
 166         priv = kzalloc(sizeof(struct tda826x_priv), GFP_KERNEL);
 167         if (priv == NULL)
 168                 return NULL;
 169
 170         priv->i2c_address = addr;
 171         priv->i2c = i2c;
 172         priv->has_loopthrough = has_loopthrough;
 173
 174         memcpy(&fe->ops.tuner_ops, &tda826x_tuner_ops, sizeof(struct dvb_tuner_ops));
 175
 176         fe->tuner_priv = priv;
 177
 178         return fe;
 179 }
 180 EXPORT_SYMBOL(tda826x_attach);
 181
 182 module_param(debug, int, 0644);
 183 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 184
 185 MODULE_DESCRIPTION("DVB TDA826x driver");
 186 MODULE_AUTHOR("Andrew de Quincey");
 187 MODULE_LICENSE("GPL");