media/dvb-frontends/tda826x.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002   /*
0003      Driver for Philips tda8262/tda8263 DVBS Silicon tuners
0004
0005      (c) 2006 Andrew de Quincey
0006
0007
0008   */
0009
0010 #include <linux/slab.h>
0011 #include <linux/module.h>
0012 #include <linux/dvb/frontend.h>
0013 #include <asm/types.h>
0014
0015 #include "tda826x.h"
0016
0017 static int debug;
0018 #define dprintk(args...) \
0019     do { \
0020         if (debug) printk(KERN_DEBUG "tda826x: " args); \
0021     } while (0)
0022
0023 struct tda826x_priv {
0024     /* i2c details */
0025     int i2c_address;
0026     struct i2c_adapter *i2c;
0027     u8 has_loopthrough:1;
0028     u32 frequency;
0029 };
0030
0031 static void tda826x_release(struct dvb_frontend *fe)
0032 {
0033     kfree(fe->tuner_priv);
0034     fe->tuner_priv = NULL;
0035 }
0036
0037 static int tda826x_sleep(struct dvb_frontend *fe)
0038 {
0039     struct tda826x_priv *priv = fe->tuner_priv;
0040     int ret;
0041     u8 buf [] = { 0x00, 0x8d };
0042     struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 2 };
0043
0044     dprintk("%s:\n", __func__);
0045
0046     if (!priv->has_loopthrough)
0047         buf[1] = 0xad;
0048
0049     if (fe->ops.i2c_gate_ctrl)
0050         fe->ops.i2c_gate_ctrl(fe, 1);
0051     if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
0052         dprintk("%s: i2c error\n", __func__);
0053     }
0054     if (fe->ops.i2c_gate_ctrl)
0055         fe->ops.i2c_gate_ctrl(fe, 0);
0056
0057     return (ret == 1) ? 0 : ret;
0058 }
0059
0060 static int tda826x_set_params(struct dvb_frontend *fe)
0061 {
0062     struct dtv_frontend_properties *p = &fe->dtv_property_cache;
0063     struct tda826x_priv *priv = fe->tuner_priv;
0064     int ret;
0065     u32 div;
0066     u32 ksyms;
0067     u32 bandwidth;
0068     u8 buf [11];
0069     struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 11 };
0070
0071     dprintk("%s:\n", __func__);
0072
0073     div = (p->frequency + (1000-1)) / 1000;
0074
0075     /* BW = ((1 + RO) * SR/2 + 5) * 1.3      [SR in MSPS, BW in MHz] */
0076     /* with R0 = 0.35 and some transformations: */
0077     ksyms = p->symbol_rate / 1000;
0078     bandwidth = (878 * ksyms + 6500000) / 1000000 + 1;
0079     if (bandwidth < 5)
0080         bandwidth = 5;
0081     else if (bandwidth > 36)
0082         bandwidth = 36;
0083
0084     buf[0] = 0x00; // subaddress
0085     buf[1] = 0x09; // powerdown RSSI + the magic value 1
0086     if (!priv->has_loopthrough)
0087         buf[1] |= 0x20; // power down loopthrough if not needed
0088     buf[2] = (1<<5) | 0x0b; // 1Mhz + 0.45 VCO
0089     buf[3] = div >> 7;
0090     buf[4] = div << 1;
0091     buf[5] = ((bandwidth - 5) << 3) | 7; /* baseband cut-off */
0092     buf[6] = 0xfe; // baseband gain 9 db + no RF attenuation
0093     buf[7] = 0x83; // charge pumps at high, tests off
0094     buf[8] = 0x80; // recommended value 4 for AMPVCO + disable ports.
0095     buf[9] = 0x1a; // normal caltime + recommended values for SELTH + SELVTL
0096     buf[10] = 0xd4; // recommended value 13 for BBIAS + unknown bit set on
0097
0098     if (fe->ops.i2c_gate_ctrl)
0099         fe->ops.i2c_gate_ctrl(fe, 1);
0100     if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
0101         dprintk("%s: i2c error\n", __func__);
0102     }
0103     if (fe->ops.i2c_gate_ctrl)
0104         fe->ops.i2c_gate_ctrl(fe, 0);
0105
0106     priv->frequency = div * 1000;
0107
0108     return (ret == 1) ? 0 : ret;
0109 }
0110
0111 static int tda826x_get_frequency(struct dvb_frontend *fe, u32 *frequency)
0112 {
0113     struct tda826x_priv *priv = fe->tuner_priv;
0114     *frequency = priv->frequency;
0115     return 0;
0116 }
0117
0118 static const struct dvb_tuner_ops tda826x_tuner_ops = {
0119     .info = {
0120         .name = "Philips TDA826X",
0121         .frequency_min_hz =  950 * MHz,
0122         .frequency_max_hz = 2175 * MHz
0123     },
0124     .release = tda826x_release,
0125     .sleep = tda826x_sleep,
0126     .set_params = tda826x_set_params,
0127     .get_frequency = tda826x_get_frequency,
0128 };
0129
0130 struct dvb_frontend *tda826x_attach(struct dvb_frontend *fe, int addr, struct i2c_adapter *i2c, int has_loopthrough)
0131 {
0132     struct tda826x_priv *priv = NULL;
0133     u8 b1 [] = { 0, 0 };
0134     struct i2c_msg msg[2] = {
0135         { .addr = addr, .flags = 0,        .buf = NULL, .len = 0 },
0136         { .addr = addr, .flags = I2C_M_RD, .buf = b1, .len = 2 }
0137     };
0138     int ret;
0139
0140     dprintk("%s:\n", __func__);
0141
0142     if (fe->ops.i2c_gate_ctrl)
0143         fe->ops.i2c_gate_ctrl(fe, 1);
0144     ret = i2c_transfer (i2c, msg, 2);
0145     if (fe->ops.i2c_gate_ctrl)
0146         fe->ops.i2c_gate_ctrl(fe, 0);
0147
0148     if (ret != 2)
0149         return NULL;
0150     if (!(b1[1] & 0x80))
0151         return NULL;
0152
0153     priv = kzalloc(sizeof(struct tda826x_priv), GFP_KERNEL);
0154     if (priv == NULL)
0155         return NULL;
0156
0157     priv->i2c_address = addr;
0158     priv->i2c = i2c;
0159     priv->has_loopthrough = has_loopthrough;
0160
0161     memcpy(&fe->ops.tuner_ops, &tda826x_tuner_ops, sizeof(struct dvb_tuner_ops));
0162
0163     fe->tuner_priv = priv;
0164
0165     return fe;
0166 }
0167 EXPORT_SYMBOL(tda826x_attach);
0168
0169 module_param(debug, int, 0644);
0170 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
0171
0172 MODULE_DESCRIPTION("DVB TDA826x driver");
0173 MODULE_AUTHOR("Andrew de Quincey");
0174 MODULE_LICENSE("GPL");