1 /* 2 TDA8261 8PSK/QPSK tuner driver 3 Copyright (C) Manu Abraham (abraham.manu@gmail.com) 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 2 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program; if not, write to the Free Software 17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 */ 19 20 21 #include <linux/init.h> 22 #include <linux/kernel.h> 23 #include <linux/module.h> 24 #include <linux/slab.h> 25 26 #include <media/dvb_frontend.h> 27 #include "tda8261.h" 28 29 struct tda8261_state { 30 struct dvb_frontend *fe; 31 struct i2c_adapter *i2c; 32 const struct tda8261_config *config; 33 34 /* state cache */ 35 u32 frequency; 36 u32 bandwidth; 37 }; 38 39 static int tda8261_read(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 = I2C_M_RD,.buf = buf, .len = 1 }; 44 45 if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) 46 pr_err("%s: read error, err=%d\n", __func__, err); 47 48 return err; 49 } 50 51 static int tda8261_write(struct tda8261_state *state, u8 *buf) 52 { 53 const struct tda8261_config *config = state->config; 54 int err = 0; 55 struct i2c_msg msg = { .addr = config->addr, .flags = 0, .buf = buf, .len = 4 }; 56 57 if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) 58 pr_err("%s: write error, err=%d\n", __func__, err); 59 60 return err; 61 } 62 63 static int tda8261_get_status(struct dvb_frontend *fe, u32 *status) 64 { 65 struct tda8261_state *state = fe->tuner_priv; 66 u8 result = 0; 67 int err = 0; 68 69 *status = 0; 70 71 if ((err = tda8261_read(state, &result)) < 0) { 72 pr_err("%s: I/O Error\n", __func__); 73 return err; 74 } 75 if ((result >> 6) & 0x01) { 76 pr_debug("%s: Tuner Phase Locked\n", __func__); 77 *status = 1; 78 } 79 80 return err; 81 } 82 83 static const u32 div_tab[] = { 2000, 1000, 500, 250, 125 }; /* kHz */ 84 static const u8 ref_div[] = { 0x00, 0x01, 0x02, 0x05, 0x07 }; 85 86 static int tda8261_get_frequency(struct dvb_frontend *fe, u32 *frequency) 87 { 88 struct tda8261_state *state = fe->tuner_priv; 89 90 *frequency = state->frequency; 91 92 return 0; 93 } 94 95 static int tda8261_set_params(struct dvb_frontend *fe) 96 { 97 struct dtv_frontend_properties *c = &fe->dtv_property_cache; 98 struct tda8261_state *state = fe->tuner_priv; 99 const struct tda8261_config *config = state->config; 100 u32 frequency, N, status = 0; 101 u8 buf[4]; 102 int err = 0; 103 104 /* 105 * N = Max VCO Frequency / Channel Spacing 106 * Max VCO Frequency = VCO frequency + (channel spacing - 1) 107 * (to account for half channel spacing on either side) 108 */ 109 frequency = c->frequency; 110 if ((frequency < 950000) || (frequency > 2150000)) { 111 pr_warn("%s: Frequency beyond limits, frequency=%d\n", 112 __func__, frequency); 113 return -EINVAL; 114 } 115 N = (frequency + (div_tab[config->step_size] - 1)) / div_tab[config->step_size]; 116 pr_debug("%s: Step size=%d, Divider=%d, PG=0x%02x (%d)\n", 117 __func__, config->step_size, div_tab[config->step_size], N, N); 118 119 buf[0] = (N >> 8) & 0xff; 120 buf[1] = N & 0xff; 121 buf[2] = (0x01 << 7) | ((ref_div[config->step_size] & 0x07) << 1); 122 123 if (frequency < 1450000) 124 buf[3] = 0x00; 125 else if (frequency < 2000000) 126 buf[3] = 0x40; 127 else if (frequency < 2150000) 128 buf[3] = 0x80; 129 130 /* Set params */ 131 err = tda8261_write(state, buf); 132 if (err < 0) { 133 pr_err("%s: I/O Error\n", __func__); 134 return err; 135 } 136 /* sleep for some time */ 137 pr_debug("%s: Waiting to Phase LOCK\n", __func__); 138 msleep(20); 139 /* check status */ 140 if ((err = tda8261_get_status(fe, &status)) < 0) { 141 pr_err("%s: I/O Error\n", __func__); 142 return err; 143 } 144 if (status == 1) { 145 pr_debug("%s: Tuner Phase locked: status=%d\n", __func__, 146 status); 147 state->frequency = frequency; /* cache successful state */ 148 } else { 149 pr_debug("%s: No Phase lock: status=%d\n", __func__, status); 150 } 151 152 return 0; 153 } 154 155 static void tda8261_release(struct dvb_frontend *fe) 156 { 157 struct tda8261_state *state = fe->tuner_priv; 158 159 fe->tuner_priv = NULL; 160 kfree(state); 161 } 162 163 static const struct dvb_tuner_ops tda8261_ops = { 164 165 .info = { 166 .name = "TDA8261", 167 .frequency_min_hz = 950 * MHz, 168 .frequency_max_hz = 2150 * MHz, 169 }, 170 171 .set_params = tda8261_set_params, 172 .get_frequency = tda8261_get_frequency, 173 .get_status = tda8261_get_status, 174 .release = tda8261_release 175 }; 176 177 struct dvb_frontend *tda8261_attach(struct dvb_frontend *fe, 178 const struct tda8261_config *config, 179 struct i2c_adapter *i2c) 180 { 181 struct tda8261_state *state = NULL; 182 183 if ((state = kzalloc(sizeof (struct tda8261_state), GFP_KERNEL)) == NULL) 184 goto exit; 185 186 state->config = config; 187 state->i2c = i2c; 188 state->fe = fe; 189 fe->tuner_priv = state; 190 fe->ops.tuner_ops = tda8261_ops; 191 192 fe->ops.tuner_ops.info.frequency_step_hz = div_tab[config->step_size] * kHz; 193 194 pr_info("%s: Attaching TDA8261 8PSK/QPSK tuner\n", __func__); 195 196 return fe; 197 198 exit: 199 kfree(state); 200 return NULL; 201 } 202 203 EXPORT_SYMBOL(tda8261_attach); 204 205 MODULE_AUTHOR("Manu Abraham"); 206 MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner"); 207 MODULE_LICENSE("GPL"); 208