1/*
2 * MaxLinear MxL301RF OFDM tuner driver
3 *
4 * Copyright (C) 2014 Akihiro Tsukada <tskd08@gmail.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation version 2.
9 *
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 * GNU General Public License for more details.
15 */
16
17/*
18 * NOTICE:
19 * This driver is incomplete and lacks init/config of the chips,
20 * as the necessary info is not disclosed.
21 * Other features like get_if_frequency() are missing as well.
22 * It assumes that users of this driver (such as a PCI bridge of
23 * DTV receiver cards) properly init and configure the chip
24 * via I2C *before* calling this driver's init() function.
25 *
26 * Currently, PT3 driver is the only one that uses this driver,
27 * and contains init/config code in its firmware.
28 * Thus some part of the code might be dependent on PT3 specific config.
29 */
30
31#include <linux/kernel.h>
32#include "mxl301rf.h"
33
34struct mxl301rf_state {
35	struct mxl301rf_config cfg;
36	struct i2c_client *i2c;
37};
38
39static struct mxl301rf_state *cfg_to_state(struct mxl301rf_config *c)
40{
41	return container_of(c, struct mxl301rf_state, cfg);
42}
43
44static int raw_write(struct mxl301rf_state *state, const u8 *buf, int len)
45{
46	int ret;
47
48	ret = i2c_master_send(state->i2c, buf, len);
49	if (ret >= 0 && ret < len)
50		ret = -EIO;
51	return (ret == len) ? 0 : ret;
52}
53
54static int reg_write(struct mxl301rf_state *state, u8 reg, u8 val)
55{
56	u8 buf[2] = { reg, val };
57
58	return raw_write(state, buf, 2);
59}
60
61static int reg_read(struct mxl301rf_state *state, u8 reg, u8 *val)
62{
63	u8 wbuf[2] = { 0xfb, reg };
64	int ret;
65
66	ret = raw_write(state, wbuf, sizeof(wbuf));
67	if (ret == 0)
68		ret = i2c_master_recv(state->i2c, val, 1);
69	if (ret >= 0 && ret < 1)
70		ret = -EIO;
71	return (ret == 1) ? 0 : ret;
72}
73
74/* tuner_ops */
75
76/* get RSSI and update propery cache, set to *out in % */
77static int mxl301rf_get_rf_strength(struct dvb_frontend *fe, u16 *out)
78{
79	struct mxl301rf_state *state;
80	int ret;
81	u8  rf_in1, rf_in2, rf_off1, rf_off2;
82	u16 rf_in, rf_off;
83	s64 level;
84	struct dtv_fe_stats *rssi;
85
86	rssi = &fe->dtv_property_cache.strength;
87	rssi->len = 1;
88	rssi->stat[0].scale = FE_SCALE_NOT_AVAILABLE;
89	*out = 0;
90
91	state = fe->tuner_priv;
92	ret = reg_write(state, 0x14, 0x01);
93	if (ret < 0)
94		return ret;
95	usleep_range(1000, 2000);
96
97	ret = reg_read(state, 0x18, &rf_in1);
98	if (ret == 0)
99		ret = reg_read(state, 0x19, &rf_in2);
100	if (ret == 0)
101		ret = reg_read(state, 0xd6, &rf_off1);
102	if (ret == 0)
103		ret = reg_read(state, 0xd7, &rf_off2);
104	if (ret != 0)
105		return ret;
106
107	rf_in = (rf_in2 & 0x07) << 8 | rf_in1;
108	rf_off = (rf_off2 & 0x0f) << 5 | (rf_off1 >> 3);
109	level = rf_in - rf_off - (113 << 3); /* x8 dBm */
110	level = level * 1000 / 8;
111	rssi->stat[0].svalue = level;
112	rssi->stat[0].scale = FE_SCALE_DECIBEL;
113	/* *out = (level - min) * 100 / (max - min) */
114	*out = (rf_in - rf_off + (1 << 9) - 1) * 100 / ((5 << 9) - 2);
115	return 0;
116}
117
118/* spur shift parameters */
119struct shf {
120	u32	freq;		/* Channel center frequency */
121	u32	ofst_th;	/* Offset frequency threshold */
122	u8	shf_val;	/* Spur shift value */
123	u8	shf_dir;	/* Spur shift direction */
124};
125
126static const struct shf shf_tab[] = {
127	{  64500, 500, 0x92, 0x07 },
128	{ 191500, 300, 0xe2, 0x07 },
129	{ 205500, 500, 0x2c, 0x04 },
130	{ 212500, 500, 0x1e, 0x04 },
131	{ 226500, 500, 0xd4, 0x07 },
132	{  99143, 500, 0x9c, 0x07 },
133	{ 173143, 500, 0xd4, 0x07 },
134	{ 191143, 300, 0xd4, 0x07 },
135	{ 207143, 500, 0xce, 0x07 },
136	{ 225143, 500, 0xce, 0x07 },
137	{ 243143, 500, 0xd4, 0x07 },
138	{ 261143, 500, 0xd4, 0x07 },
139	{ 291143, 500, 0xd4, 0x07 },
140	{ 339143, 500, 0x2c, 0x04 },
141	{ 117143, 500, 0x7a, 0x07 },
142	{ 135143, 300, 0x7a, 0x07 },
143	{ 153143, 500, 0x01, 0x07 }
144};
145
146struct reg_val {
147	u8 reg;
148	u8 val;
149} __attribute__ ((__packed__));
150
151static const struct reg_val set_idac[] = {
152	{ 0x0d, 0x00 },
153	{ 0x0c, 0x67 },
154	{ 0x6f, 0x89 },
155	{ 0x70, 0x0c },
156	{ 0x6f, 0x8a },
157	{ 0x70, 0x0e },
158	{ 0x6f, 0x8b },
159	{ 0x70, 0x1c },
160};
161
162static int mxl301rf_set_params(struct dvb_frontend *fe)
163{
164	struct reg_val tune0[] = {
165		{ 0x13, 0x00 },		/* abort tuning */
166		{ 0x3b, 0xc0 },
167		{ 0x3b, 0x80 },
168		{ 0x10, 0x95 },		/* BW */
169		{ 0x1a, 0x05 },
170		{ 0x61, 0x00 },		/* spur shift value (placeholder) */
171		{ 0x62, 0xa0 }		/* spur shift direction (placeholder) */
172	};
173
174	struct reg_val tune1[] = {
175		{ 0x11, 0x40 },		/* RF frequency L (placeholder) */
176		{ 0x12, 0x0e },		/* RF frequency H (placeholder) */
177		{ 0x13, 0x01 }		/* start tune */
178	};
179
180	struct mxl301rf_state *state;
181	u32 freq;
182	u16 f;
183	u32 tmp, div;
184	int i, ret;
185
186	state = fe->tuner_priv;
187	freq = fe->dtv_property_cache.frequency;
188
189	/* spur shift function (for analog) */
190	for (i = 0; i < ARRAY_SIZE(shf_tab); i++) {
191		if (freq >= (shf_tab[i].freq - shf_tab[i].ofst_th) * 1000 &&
192		    freq <= (shf_tab[i].freq + shf_tab[i].ofst_th) * 1000) {
193			tune0[5].val = shf_tab[i].shf_val;
194			tune0[6].val = 0xa0 | shf_tab[i].shf_dir;
195			break;
196		}
197	}
198	ret = raw_write(state, (u8 *) tune0, sizeof(tune0));
199	if (ret < 0)
200		goto failed;
201	usleep_range(3000, 4000);
202
203	/* convert freq to 10.6 fixed point float [MHz] */
204	f = freq / 1000000;
205	tmp = freq % 1000000;
206	div = 1000000;
207	for (i = 0; i < 6; i++) {
208		f <<= 1;
209		div >>= 1;
210		if (tmp > div) {
211			tmp -= div;
212			f |= 1;
213		}
214	}
215	if (tmp > 7812)
216		f++;
217	tune1[0].val = f & 0xff;
218	tune1[1].val = f >> 8;
219	ret = raw_write(state, (u8 *) tune1, sizeof(tune1));
220	if (ret < 0)
221		goto failed;
222	msleep(31);
223
224	ret = reg_write(state, 0x1a, 0x0d);
225	if (ret < 0)
226		goto failed;
227	ret = raw_write(state, (u8 *) set_idac, sizeof(set_idac));
228	if (ret < 0)
229		goto failed;
230	return 0;
231
232failed:
233	dev_warn(&state->i2c->dev, "(%s) failed. [adap%d-fe%d]\n",
234		__func__, fe->dvb->num, fe->id);
235	return ret;
236}
237
238static const struct reg_val standby_data[] = {
239	{ 0x01, 0x00 },
240	{ 0x13, 0x00 }
241};
242
243static int mxl301rf_sleep(struct dvb_frontend *fe)
244{
245	struct mxl301rf_state *state;
246	int ret;
247
248	state = fe->tuner_priv;
249	ret = raw_write(state, (u8 *)standby_data, sizeof(standby_data));
250	if (ret < 0)
251		dev_warn(&state->i2c->dev, "(%s) failed. [adap%d-fe%d]\n",
252			__func__, fe->dvb->num, fe->id);
253	return ret;
254}
255
256
257/* init sequence is not public.
258 * the parent must have init'ed the device.
259 * just wake up here.
260 */
261static int mxl301rf_init(struct dvb_frontend *fe)
262{
263	struct mxl301rf_state *state;
264	int ret;
265
266	state = fe->tuner_priv;
267
268	ret = reg_write(state, 0x01, 0x01);
269	if (ret < 0) {
270		dev_warn(&state->i2c->dev, "(%s) failed. [adap%d-fe%d]\n",
271			 __func__, fe->dvb->num, fe->id);
272		return ret;
273	}
274	return 0;
275}
276
277/* I2C driver functions */
278
279static const struct dvb_tuner_ops mxl301rf_ops = {
280	.info = {
281		.name = "MaxLinear MxL301RF",
282
283		.frequency_min =  93000000,
284		.frequency_max = 803142857,
285	},
286
287	.init = mxl301rf_init,
288	.sleep = mxl301rf_sleep,
289
290	.set_params = mxl301rf_set_params,
291	.get_rf_strength = mxl301rf_get_rf_strength,
292};
293
294
295static int mxl301rf_probe(struct i2c_client *client,
296			  const struct i2c_device_id *id)
297{
298	struct mxl301rf_state *state;
299	struct mxl301rf_config *cfg;
300	struct dvb_frontend *fe;
301
302	state = kzalloc(sizeof(*state), GFP_KERNEL);
303	if (!state)
304		return -ENOMEM;
305
306	state->i2c = client;
307	cfg = client->dev.platform_data;
308
309	memcpy(&state->cfg, cfg, sizeof(state->cfg));
310	fe = cfg->fe;
311	fe->tuner_priv = state;
312	memcpy(&fe->ops.tuner_ops, &mxl301rf_ops, sizeof(mxl301rf_ops));
313
314	i2c_set_clientdata(client, &state->cfg);
315	dev_info(&client->dev, "MaxLinear MxL301RF attached.\n");
316	return 0;
317}
318
319static int mxl301rf_remove(struct i2c_client *client)
320{
321	struct mxl301rf_state *state;
322
323	state = cfg_to_state(i2c_get_clientdata(client));
324	state->cfg.fe->tuner_priv = NULL;
325	kfree(state);
326	return 0;
327}
328
329
330static const struct i2c_device_id mxl301rf_id[] = {
331	{"mxl301rf", 0},
332	{}
333};
334MODULE_DEVICE_TABLE(i2c, mxl301rf_id);
335
336static struct i2c_driver mxl301rf_driver = {
337	.driver = {
338		.name	= "mxl301rf",
339	},
340	.probe		= mxl301rf_probe,
341	.remove		= mxl301rf_remove,
342	.id_table	= mxl301rf_id,
343};
344
345module_i2c_driver(mxl301rf_driver);
346
347MODULE_DESCRIPTION("MaxLinear MXL301RF tuner");
348MODULE_AUTHOR("Akihiro TSUKADA");
349MODULE_LICENSE("GPL");
350