1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 TDA8261 8PSK/QPSK tuner driver 4 Copyright (C) Manu Abraham (abraham.manu@gmail.com) 5 6 */ 7 8 9 #include <linux/init.h> 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/slab.h> 13 14 #include <media/dvb_frontend.h> 15 #include "tda8261.h" 16 17 struct tda8261_state { 18 struct dvb_frontend *fe; 19 struct i2c_adapter *i2c; 20 const struct tda8261_config *config; 21 22 /* state cache */ 23 u32 frequency; 24 u32 bandwidth; 25 }; 26 27 static int tda8261_read(struct tda8261_state *state, u8 *buf) 28 { 29 const struct tda8261_config *config = state->config; 30 int err = 0; 31 struct i2c_msg msg = { .addr = config->addr, .flags = I2C_M_RD,.buf = buf, .len = 1 }; 32 33 if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) 34 pr_err("%s: read error, err=%d\n", __func__, err); 35 36 return err; 37 } 38 39 static int tda8261_write(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 = 0, .buf = buf, .len = 4 }; 44 45 if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) 46 pr_err("%s: write error, err=%d\n", __func__, err); 47 48 return err; 49 } 50 51 static int tda8261_get_status(struct dvb_frontend *fe, u32 *status) 52 { 53 struct tda8261_state *state = fe->tuner_priv; 54 u8 result = 0; 55 int err = 0; 56 57 *status = 0; 58 59 if ((err = tda8261_read(state, &result)) < 0) { 60 pr_err("%s: I/O Error\n", __func__); 61 return err; 62 } 63 if ((result >> 6) & 0x01) { 64 pr_debug("%s: Tuner Phase Locked\n", __func__); 65 *status = 1; 66 } 67 68 return err; 69 } 70 71 static const u32 div_tab[] = { 2000, 1000, 500, 250, 125 }; /* kHz */ 72 static const u8 ref_div[] = { 0x00, 0x01, 0x02, 0x05, 0x07 }; 73 74 static int tda8261_get_frequency(struct dvb_frontend *fe, u32 *frequency) 75 { 76 struct tda8261_state *state = fe->tuner_priv; 77 78 *frequency = state->frequency; 79 80 return 0; 81 } 82 83 static int tda8261_set_params(struct dvb_frontend *fe) 84 { 85 struct dtv_frontend_properties *c = &fe->dtv_property_cache; 86 struct tda8261_state *state = fe->tuner_priv; 87 const struct tda8261_config *config = state->config; 88 u32 frequency, N, status = 0; 89 u8 buf[4]; 90 int err = 0; 91 92 /* 93 * N = Max VCO Frequency / Channel Spacing 94 * Max VCO Frequency = VCO frequency + (channel spacing - 1) 95 * (to account for half channel spacing on either side) 96 */ 97 frequency = c->frequency; 98 if ((frequency < 950000) || (frequency > 2150000)) { 99 pr_warn("%s: Frequency beyond limits, frequency=%d\n", 100 __func__, frequency); 101 return -EINVAL; 102 } 103 N = (frequency + (div_tab[config->step_size] - 1)) / div_tab[config->step_size]; 104 pr_debug("%s: Step size=%d, Divider=%d, PG=0x%02x (%d)\n", 105 __func__, config->step_size, div_tab[config->step_size], N, N); 106 107 buf[0] = (N >> 8) & 0xff; 108 buf[1] = N & 0xff; 109 buf[2] = (0x01 << 7) | ((ref_div[config->step_size] & 0x07) << 1); 110 111 if (frequency < 1450000) 112 buf[3] = 0x00; 113 else if (frequency < 2000000) 114 buf[3] = 0x40; 115 else if (frequency < 2150000) 116 buf[3] = 0x80; 117 118 /* Set params */ 119 err = tda8261_write(state, buf); 120 if (err < 0) { 121 pr_err("%s: I/O Error\n", __func__); 122 return err; 123 } 124 /* sleep for some time */ 125 pr_debug("%s: Waiting to Phase LOCK\n", __func__); 126 msleep(20); 127 /* check status */ 128 if ((err = tda8261_get_status(fe, &status)) < 0) { 129 pr_err("%s: I/O Error\n", __func__); 130 return err; 131 } 132 if (status == 1) { 133 pr_debug("%s: Tuner Phase locked: status=%d\n", __func__, 134 status); 135 state->frequency = frequency; /* cache successful state */ 136 } else { 137 pr_debug("%s: No Phase lock: status=%d\n", __func__, status); 138 } 139 140 return 0; 141 } 142 143 static void tda8261_release(struct dvb_frontend *fe) 144 { 145 struct tda8261_state *state = fe->tuner_priv; 146 147 fe->tuner_priv = NULL; 148 kfree(state); 149 } 150 151 static const struct dvb_tuner_ops tda8261_ops = { 152 153 .info = { 154 .name = "TDA8261", 155 .frequency_min_hz = 950 * MHz, 156 .frequency_max_hz = 2150 * MHz, 157 }, 158 159 .set_params = tda8261_set_params, 160 .get_frequency = tda8261_get_frequency, 161 .get_status = tda8261_get_status, 162 .release = tda8261_release 163 }; 164 165 struct dvb_frontend *tda8261_attach(struct dvb_frontend *fe, 166 const struct tda8261_config *config, 167 struct i2c_adapter *i2c) 168 { 169 struct tda8261_state *state = NULL; 170 171 if ((state = kzalloc(sizeof (struct tda8261_state), GFP_KERNEL)) == NULL) 172 goto exit; 173 174 state->config = config; 175 state->i2c = i2c; 176 state->fe = fe; 177 fe->tuner_priv = state; 178 fe->ops.tuner_ops = tda8261_ops; 179 180 fe->ops.tuner_ops.info.frequency_step_hz = div_tab[config->step_size] * kHz; 181 182 pr_info("%s: Attaching TDA8261 8PSK/QPSK tuner\n", __func__); 183 184 return fe; 185 186 exit: 187 kfree(state); 188 return NULL; 189 } 190 191 EXPORT_SYMBOL_GPL(tda8261_attach); 192 193 MODULE_AUTHOR("Manu Abraham"); 194 MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner"); 195 MODULE_LICENSE("GPL"); 196