drivers/media/dvb-frontends/tda826x.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2   /*
   3      Driver for Philips tda8262/tda8263 DVBS Silicon tuners
   4
   5      (c) 2006 Andrew de Quincey
   6
   7
   8   */
   9
  10 #include <linux/slab.h>
  11 #include <linux/module.h>
  12 #include <linux/dvb/frontend.h>
  13 #include <asm/types.h>
  14
  15 #include "tda826x.h"
  16
  17 static int debug;
  18 #define dprintk(args...) \
  19         do { \
  20                 if (debug) printk(KERN_DEBUG "tda826x: " args); \
  21         } while (0)
  22
  23 struct tda826x_priv {
  24         /* i2c details */
  25         int i2c_address;
  26         struct i2c_adapter *i2c;
  27         u8 has_loopthrough:1;
  28         u32 frequency;
  29 };
  30
  31 static void tda826x_release(struct dvb_frontend *fe)
  32 {
  33         kfree(fe->tuner_priv);
  34         fe->tuner_priv = NULL;
  35 }
  36
  37 static int tda826x_sleep(struct dvb_frontend *fe)
  38 {
  39         struct tda826x_priv *priv = fe->tuner_priv;
  40         int ret;
  41         u8 buf [] = { 0x00, 0x8d };
  42         struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 2 };
  43
  44         dprintk("%s:\n", __func__);
  45
  46         if (!priv->has_loopthrough)
  47                 buf[1] = 0xad;
  48
  49         if (fe->ops.i2c_gate_ctrl)
  50                 fe->ops.i2c_gate_ctrl(fe, 1);
  51         if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
  52                 dprintk("%s: i2c error\n", __func__);
  53         }
  54         if (fe->ops.i2c_gate_ctrl)
  55                 fe->ops.i2c_gate_ctrl(fe, 0);
  56
  57         return (ret == 1) ? 0 : ret;
  58 }
  59
  60 static int tda826x_set_params(struct dvb_frontend *fe)
  61 {
  62         struct dtv_frontend_properties *p = &fe->dtv_property_cache;
  63         struct tda826x_priv *priv = fe->tuner_priv;
  64         int ret;
  65         u32 div;
  66         u32 ksyms;
  67         u32 bandwidth;
  68         u8 buf [11];
  69         struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 11 };
  70
  71         dprintk("%s:\n", __func__);
  72
  73         div = (p->frequency + (1000-1)) / 1000;
  74
  75         /* BW = ((1 + RO) * SR/2 + 5) * 1.3      [SR in MSPS, BW in MHz] */
  76         /* with R0 = 0.35 and some transformations: */
  77         ksyms = p->symbol_rate / 1000;
  78         bandwidth = (878 * ksyms + 6500000) / 1000000 + 1;
  79         if (bandwidth < 5)
  80                 bandwidth = 5;
  81         else if (bandwidth > 36)
  82                 bandwidth = 36;
  83
  84         buf[0] = 0x00; // subaddress
  85         buf[1] = 0x09; // powerdown RSSI + the magic value 1
  86         if (!priv->has_loopthrough)
  87                 buf[1] |= 0x20; // power down loopthrough if not needed
  88         buf[2] = (1<<5) | 0x0b; // 1Mhz + 0.45 VCO
  89         buf[3] = div >> 7;
  90         buf[4] = div << 1;
  91         buf[5] = ((bandwidth - 5) << 3) | 7; /* baseband cut-off */
  92         buf[6] = 0xfe; // baseband gain 9 db + no RF attenuation
  93         buf[7] = 0x83; // charge pumps at high, tests off
  94         buf[8] = 0x80; // recommended value 4 for AMPVCO + disable ports.
  95         buf[9] = 0x1a; // normal caltime + recommended values for SELTH + SELVTL
  96         buf[10] = 0xd4; // recommended value 13 for BBIAS + unknown bit set on
  97
  98         if (fe->ops.i2c_gate_ctrl)
  99                 fe->ops.i2c_gate_ctrl(fe, 1);
 100         if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
 101                 dprintk("%s: i2c error\n", __func__);
 102         }
 103         if (fe->ops.i2c_gate_ctrl)
 104                 fe->ops.i2c_gate_ctrl(fe, 0);
 105
 106         priv->frequency = div * 1000;
 107
 108         return (ret == 1) ? 0 : ret;
 109 }
 110
 111 static int tda826x_get_frequency(struct dvb_frontend *fe, u32 *frequency)
 112 {
 113         struct tda826x_priv *priv = fe->tuner_priv;
 114         *frequency = priv->frequency;
 115         return 0;
 116 }
 117
 118 static const struct dvb_tuner_ops tda826x_tuner_ops = {
 119         .info = {
 120                 .name = "Philips TDA826X",
 121                 .frequency_min_hz =  950 * MHz,
 122                 .frequency_max_hz = 2175 * MHz
 123         },
 124         .release = tda826x_release,
 125         .sleep = tda826x_sleep,
 126         .set_params = tda826x_set_params,
 127         .get_frequency = tda826x_get_frequency,
 128 };
 129
 130 struct dvb_frontend *tda826x_attach(struct dvb_frontend *fe, int addr, struct i2c_adapter *i2c, int has_loopthrough)
 131 {
 132         struct tda826x_priv *priv = NULL;
 133         u8 b1 [] = { 0, 0 };
 134         struct i2c_msg msg[2] = {
 135                 { .addr = addr, .flags = 0,        .buf = NULL, .len = 0 },
 136                 { .addr = addr, .flags = I2C_M_RD, .buf = b1, .len = 2 }
 137         };
 138         int ret;
 139
 140         dprintk("%s:\n", __func__);
 141
 142         if (fe->ops.i2c_gate_ctrl)
 143                 fe->ops.i2c_gate_ctrl(fe, 1);
 144         ret = i2c_transfer (i2c, msg, 2);
 145         if (fe->ops.i2c_gate_ctrl)
 146                 fe->ops.i2c_gate_ctrl(fe, 0);
 147
 148         if (ret != 2)
 149                 return NULL;
 150         if (!(b1[1] & 0x80))
 151                 return NULL;
 152
 153         priv = kzalloc(sizeof(struct tda826x_priv), GFP_KERNEL);
 154         if (priv == NULL)
 155                 return NULL;
 156
 157         priv->i2c_address = addr;
 158         priv->i2c = i2c;
 159         priv->has_loopthrough = has_loopthrough;
 160
 161         memcpy(&fe->ops.tuner_ops, &tda826x_tuner_ops, sizeof(struct dvb_tuner_ops));
 162
 163         fe->tuner_priv = priv;
 164
 165         return fe;
 166 }
 167 EXPORT_SYMBOL(tda826x_attach);
 168
 169 module_param(debug, int, 0644);
 170 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 171
 172 MODULE_DESCRIPTION("DVB TDA826x driver");
 173 MODULE_AUTHOR("Andrew de Quincey");
 174 MODULE_LICENSE("GPL");