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
tda8261_read(struct tda8261_state * state,u8 * buf)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
tda8261_write(struct tda8261_state * state,u8 * buf)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
tda8261_get_status(struct dvb_frontend * fe,u32 * status)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
tda8261_get_frequency(struct dvb_frontend * fe,u32 * frequency)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
tda8261_set_params(struct dvb_frontend * fe)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
tda8261_release(struct dvb_frontend * fe)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
tda8261_attach(struct dvb_frontend * fe,const struct tda8261_config * config,struct i2c_adapter * i2c)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