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 "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_state(struct dvb_frontend *fe,
87 			     enum tuner_param param,
88 			     struct tuner_state *tstate)
89 {
90 	struct tda8261_state *state = fe->tuner_priv;
91 	int err = 0;
92 
93 	switch (param) {
94 	case DVBFE_TUNER_FREQUENCY:
95 		tstate->frequency = state->frequency;
96 		break;
97 	case DVBFE_TUNER_BANDWIDTH:
98 		tstate->bandwidth = 40000000; /* FIXME! need to calculate Bandwidth */
99 		break;
100 	default:
101 		pr_err("%s: Unknown parameter (param=%d)\n", __func__, param);
102 		err = -EINVAL;
103 		break;
104 	}
105 
106 	return err;
107 }
108 
109 static int tda8261_set_state(struct dvb_frontend *fe,
110 			     enum tuner_param param,
111 			     struct tuner_state *tstate)
112 {
113 	struct tda8261_state *state = fe->tuner_priv;
114 	const struct tda8261_config *config = state->config;
115 	u32 frequency, N, status = 0;
116 	u8 buf[4];
117 	int err = 0;
118 
119 	if (param & DVBFE_TUNER_FREQUENCY) {
120 		/**
121 		 * N = Max VCO Frequency / Channel Spacing
122 		 * Max VCO Frequency = VCO frequency + (channel spacing - 1)
123 		 * (to account for half channel spacing on either side)
124 		 */
125 		frequency = tstate->frequency;
126 		if ((frequency < 950000) || (frequency > 2150000)) {
127 			pr_warn("%s: Frequency beyond limits, frequency=%d\n", __func__, frequency);
128 			return -EINVAL;
129 		}
130 		N = (frequency + (div_tab[config->step_size] - 1)) / div_tab[config->step_size];
131 		pr_debug("%s: Step size=%d, Divider=%d, PG=0x%02x (%d)\n",
132 			__func__, config->step_size, div_tab[config->step_size], N, N);
133 
134 		buf[0] = (N >> 8) & 0xff;
135 		buf[1] = N & 0xff;
136 		buf[2] = (0x01 << 7) | ((ref_div[config->step_size] & 0x07) << 1);
137 
138 		if (frequency < 1450000)
139 			buf[3] = 0x00;
140 		else if (frequency < 2000000)
141 			buf[3] = 0x40;
142 		else if (frequency < 2150000)
143 			buf[3] = 0x80;
144 
145 		/* Set params */
146 		if ((err = tda8261_write(state, buf)) < 0) {
147 			pr_err("%s: I/O Error\n", __func__);
148 			return err;
149 		}
150 		/* sleep for some time */
151 		pr_debug("%s: Waiting to Phase LOCK\n", __func__);
152 		msleep(20);
153 		/* check status */
154 		if ((err = tda8261_get_status(fe, &status)) < 0) {
155 			pr_err("%s: I/O Error\n", __func__);
156 			return err;
157 		}
158 		if (status == 1) {
159 			pr_debug("%s: Tuner Phase locked: status=%d\n", __func__, status);
160 			state->frequency = frequency; /* cache successful state */
161 		} else {
162 			pr_debug("%s: No Phase lock: status=%d\n", __func__, status);
163 		}
164 	} else {
165 		pr_err("%s: Unknown parameter (param=%d)\n", __func__, param);
166 		return -EINVAL;
167 	}
168 
169 	return 0;
170 }
171 
172 static int tda8261_release(struct dvb_frontend *fe)
173 {
174 	struct tda8261_state *state = fe->tuner_priv;
175 
176 	fe->tuner_priv = NULL;
177 	kfree(state);
178 	return 0;
179 }
180 
181 static struct dvb_tuner_ops tda8261_ops = {
182 
183 	.info = {
184 		.name		= "TDA8261",
185 //		.tuner_name	= NULL,
186 		.frequency_min	=  950000,
187 		.frequency_max	= 2150000,
188 		.frequency_step = 0
189 	},
190 
191 	.set_state	= tda8261_set_state,
192 	.get_state	= tda8261_get_state,
193 	.get_status	= tda8261_get_status,
194 	.release	= tda8261_release
195 };
196 
197 struct dvb_frontend *tda8261_attach(struct dvb_frontend *fe,
198 				    const struct tda8261_config *config,
199 				    struct i2c_adapter *i2c)
200 {
201 	struct tda8261_state *state = NULL;
202 
203 	if ((state = kzalloc(sizeof (struct tda8261_state), GFP_KERNEL)) == NULL)
204 		goto exit;
205 
206 	state->config		= config;
207 	state->i2c		= i2c;
208 	state->fe		= fe;
209 	fe->tuner_priv		= state;
210 	fe->ops.tuner_ops	= tda8261_ops;
211 
212 	fe->ops.tuner_ops.info.frequency_step = div_tab[config->step_size];
213 //	fe->ops.tuner_ops.tuner_name	 = &config->buf;
214 
215 //	printk("%s: Attaching %s TDA8261 8PSK/QPSK tuner\n",
216 //		__func__, fe->ops.tuner_ops.tuner_name);
217 	pr_info("%s: Attaching TDA8261 8PSK/QPSK tuner\n", __func__);
218 
219 	return fe;
220 
221 exit:
222 	kfree(state);
223 	return NULL;
224 }
225 
226 EXPORT_SYMBOL(tda8261_attach);
227 
228 MODULE_AUTHOR("Manu Abraham");
229 MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner");
230 MODULE_LICENSE("GPL");
231