xref: /linux/drivers/media/dvb-frontends/tda826x.c (revision 74ce1896c6c65b2f8cccbf59162d542988835835)
1   /*
2      Driver for Philips tda8262/tda8263 DVBS Silicon tuners
3 
4      (c) 2006 Andrew de Quincey
5 
6      This program is free software; you can redistribute it and/or modify
7      it under the terms of the GNU General Public License as published by
8      the Free Software Foundation; either version 2 of the License, or
9      (at your option) any later version.
10 
11      This program is distributed in the hope that it will be useful,
12      but WITHOUT ANY WARRANTY; without even the implied warranty of
13      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 
15      GNU General Public License for more details.
16 
17      You should have received a copy of the GNU General Public License
18      along with this program; if not, write to the Free Software
19      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 
21   */
22 
23 #include <linux/slab.h>
24 #include <linux/module.h>
25 #include <linux/dvb/frontend.h>
26 #include <asm/types.h>
27 
28 #include "tda826x.h"
29 
30 static int debug;
31 #define dprintk(args...) \
32 	do { \
33 		if (debug) printk(KERN_DEBUG "tda826x: " args); \
34 	} while (0)
35 
36 struct tda826x_priv {
37 	/* i2c details */
38 	int i2c_address;
39 	struct i2c_adapter *i2c;
40 	u8 has_loopthrough:1;
41 	u32 frequency;
42 };
43 
44 static void tda826x_release(struct dvb_frontend *fe)
45 {
46 	kfree(fe->tuner_priv);
47 	fe->tuner_priv = NULL;
48 }
49 
50 static int tda826x_sleep(struct dvb_frontend *fe)
51 {
52 	struct tda826x_priv *priv = fe->tuner_priv;
53 	int ret;
54 	u8 buf [] = { 0x00, 0x8d };
55 	struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 2 };
56 
57 	dprintk("%s:\n", __func__);
58 
59 	if (!priv->has_loopthrough)
60 		buf[1] = 0xad;
61 
62 	if (fe->ops.i2c_gate_ctrl)
63 		fe->ops.i2c_gate_ctrl(fe, 1);
64 	if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
65 		dprintk("%s: i2c error\n", __func__);
66 	}
67 	if (fe->ops.i2c_gate_ctrl)
68 		fe->ops.i2c_gate_ctrl(fe, 0);
69 
70 	return (ret == 1) ? 0 : ret;
71 }
72 
73 static int tda826x_set_params(struct dvb_frontend *fe)
74 {
75 	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
76 	struct tda826x_priv *priv = fe->tuner_priv;
77 	int ret;
78 	u32 div;
79 	u32 ksyms;
80 	u32 bandwidth;
81 	u8 buf [11];
82 	struct i2c_msg msg = { .addr = priv->i2c_address, .flags = 0, .buf = buf, .len = 11 };
83 
84 	dprintk("%s:\n", __func__);
85 
86 	div = (p->frequency + (1000-1)) / 1000;
87 
88 	/* BW = ((1 + RO) * SR/2 + 5) * 1.3      [SR in MSPS, BW in MHz] */
89 	/* with R0 = 0.35 and some transformations: */
90 	ksyms = p->symbol_rate / 1000;
91 	bandwidth = (878 * ksyms + 6500000) / 1000000 + 1;
92 	if (bandwidth < 5)
93 		bandwidth = 5;
94 	else if (bandwidth > 36)
95 		bandwidth = 36;
96 
97 	buf[0] = 0x00; // subaddress
98 	buf[1] = 0x09; // powerdown RSSI + the magic value 1
99 	if (!priv->has_loopthrough)
100 		buf[1] |= 0x20; // power down loopthrough if not needed
101 	buf[2] = (1<<5) | 0x0b; // 1Mhz + 0.45 VCO
102 	buf[3] = div >> 7;
103 	buf[4] = div << 1;
104 	buf[5] = ((bandwidth - 5) << 3) | 7; /* baseband cut-off */
105 	buf[6] = 0xfe; // baseband gain 9 db + no RF attenuation
106 	buf[7] = 0x83; // charge pumps at high, tests off
107 	buf[8] = 0x80; // recommended value 4 for AMPVCO + disable ports.
108 	buf[9] = 0x1a; // normal caltime + recommended values for SELTH + SELVTL
109 	buf[10] = 0xd4; // recommended value 13 for BBIAS + unknown bit set on
110 
111 	if (fe->ops.i2c_gate_ctrl)
112 		fe->ops.i2c_gate_ctrl(fe, 1);
113 	if ((ret = i2c_transfer (priv->i2c, &msg, 1)) != 1) {
114 		dprintk("%s: i2c error\n", __func__);
115 	}
116 	if (fe->ops.i2c_gate_ctrl)
117 		fe->ops.i2c_gate_ctrl(fe, 0);
118 
119 	priv->frequency = div * 1000;
120 
121 	return (ret == 1) ? 0 : ret;
122 }
123 
124 static int tda826x_get_frequency(struct dvb_frontend *fe, u32 *frequency)
125 {
126 	struct tda826x_priv *priv = fe->tuner_priv;
127 	*frequency = priv->frequency;
128 	return 0;
129 }
130 
131 static const struct dvb_tuner_ops tda826x_tuner_ops = {
132 	.info = {
133 		.name = "Philips TDA826X",
134 		.frequency_min = 950000,
135 		.frequency_max = 2175000
136 	},
137 	.release = tda826x_release,
138 	.sleep = tda826x_sleep,
139 	.set_params = tda826x_set_params,
140 	.get_frequency = tda826x_get_frequency,
141 };
142 
143 struct dvb_frontend *tda826x_attach(struct dvb_frontend *fe, int addr, struct i2c_adapter *i2c, int has_loopthrough)
144 {
145 	struct tda826x_priv *priv = NULL;
146 	u8 b1 [] = { 0, 0 };
147 	struct i2c_msg msg[2] = {
148 		{ .addr = addr, .flags = 0,        .buf = NULL, .len = 0 },
149 		{ .addr = addr, .flags = I2C_M_RD, .buf = b1, .len = 2 }
150 	};
151 	int ret;
152 
153 	dprintk("%s:\n", __func__);
154 
155 	if (fe->ops.i2c_gate_ctrl)
156 		fe->ops.i2c_gate_ctrl(fe, 1);
157 	ret = i2c_transfer (i2c, msg, 2);
158 	if (fe->ops.i2c_gate_ctrl)
159 		fe->ops.i2c_gate_ctrl(fe, 0);
160 
161 	if (ret != 2)
162 		return NULL;
163 	if (!(b1[1] & 0x80))
164 		return NULL;
165 
166 	priv = kzalloc(sizeof(struct tda826x_priv), GFP_KERNEL);
167 	if (priv == NULL)
168 		return NULL;
169 
170 	priv->i2c_address = addr;
171 	priv->i2c = i2c;
172 	priv->has_loopthrough = has_loopthrough;
173 
174 	memcpy(&fe->ops.tuner_ops, &tda826x_tuner_ops, sizeof(struct dvb_tuner_ops));
175 
176 	fe->tuner_priv = priv;
177 
178 	return fe;
179 }
180 EXPORT_SYMBOL(tda826x_attach);
181 
182 module_param(debug, int, 0644);
183 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
184 
185 MODULE_DESCRIPTION("DVB TDA826x driver");
186 MODULE_AUTHOR("Andrew de Quincey");
187 MODULE_LICENSE("GPL");
188