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
29struct 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
39static 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
51static 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
63static 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
83static const u32 div_tab[] = { 2000, 1000,  500,  250,  125 }; /* kHz */
84static const u8  ref_div[] = { 0x00, 0x01, 0x02, 0x05, 0x07 };
85
86static 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
109static 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
172static 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
181static 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
197struct 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
221exit:
222	kfree(state);
223	return NULL;
224}
225
226EXPORT_SYMBOL(tda8261_attach);
227
228MODULE_AUTHOR("Manu Abraham");
229MODULE_DESCRIPTION("TDA8261 8PSK/QPSK Tuner");
230MODULE_LICENSE("GPL");
231