1 /*
2 	STB6100 Silicon Tuner
3 	Copyright (C) Manu Abraham (abraham.manu@gmail.com)
4 
5 	Copyright (C) ST Microelectronics
6 
7 	This program is free software; you can redistribute it and/or modify
8 	it under the terms of the GNU General Public License as published by
9 	the Free Software Foundation; either version 2 of the License, or
10 	(at your option) any later version.
11 
12 	This program is distributed in the hope that it will be useful,
13 	but WITHOUT ANY WARRANTY; without even the implied warranty of
14 	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 #include <linux/init.h>
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/slab.h>
26 #include <linux/string.h>
27 
28 #include "dvb_frontend.h"
29 #include "stb6100.h"
30 
31 static unsigned int verbose;
32 module_param(verbose, int, 0644);
33 
34 /* Max transfer size done by I2C transfer functions */
35 #define MAX_XFER_SIZE  64
36 
37 #define FE_ERROR		0
38 #define FE_NOTICE		1
39 #define FE_INFO			2
40 #define FE_DEBUG		3
41 
42 #define dprintk(x, y, z, format, arg...) do {						\
43 	if (z) {									\
44 		if	((x > FE_ERROR) && (x > y))					\
45 			printk(KERN_ERR "%s: " format "\n", __func__ , ##arg);		\
46 		else if	((x > FE_NOTICE) && (x > y))					\
47 			printk(KERN_NOTICE "%s: " format "\n", __func__ , ##arg);	\
48 		else if ((x > FE_INFO) && (x > y))					\
49 			printk(KERN_INFO "%s: " format "\n", __func__ , ##arg);		\
50 		else if ((x > FE_DEBUG) && (x > y))					\
51 			printk(KERN_DEBUG "%s: " format "\n", __func__ , ##arg);	\
52 	} else {									\
53 		if (x > y)								\
54 			printk(format, ##arg);						\
55 	}										\
56 } while (0)
57 
58 struct stb6100_lkup {
59 	u32 val_low;
60 	u32 val_high;
61 	u8   reg;
62 };
63 
64 static int stb6100_release(struct dvb_frontend *fe);
65 
66 static const struct stb6100_lkup lkup[] = {
67 	{       0,  950000, 0x0a },
68 	{  950000, 1000000, 0x0a },
69 	{ 1000000, 1075000, 0x0c },
70 	{ 1075000, 1200000, 0x00 },
71 	{ 1200000, 1300000, 0x01 },
72 	{ 1300000, 1370000, 0x02 },
73 	{ 1370000, 1470000, 0x04 },
74 	{ 1470000, 1530000, 0x05 },
75 	{ 1530000, 1650000, 0x06 },
76 	{ 1650000, 1800000, 0x08 },
77 	{ 1800000, 1950000, 0x0a },
78 	{ 1950000, 2150000, 0x0c },
79 	{ 2150000, 9999999, 0x0c },
80 	{       0,       0, 0x00 }
81 };
82 
83 /* Register names for easy debugging.	*/
84 static const char *stb6100_regnames[] = {
85 	[STB6100_LD]		= "LD",
86 	[STB6100_VCO]		= "VCO",
87 	[STB6100_NI]		= "NI",
88 	[STB6100_NF_LSB]	= "NF",
89 	[STB6100_K]		= "K",
90 	[STB6100_G]		= "G",
91 	[STB6100_F]		= "F",
92 	[STB6100_DLB]		= "DLB",
93 	[STB6100_TEST1]		= "TEST1",
94 	[STB6100_FCCK]		= "FCCK",
95 	[STB6100_LPEN]		= "LPEN",
96 	[STB6100_TEST3]		= "TEST3",
97 };
98 
99 /* Template for normalisation, i.e. setting unused or undocumented
100  * bits as required according to the documentation.
101  */
102 struct stb6100_regmask {
103 	u8 mask;
104 	u8 set;
105 };
106 
107 static const struct stb6100_regmask stb6100_template[] = {
108 	[STB6100_LD]		= { 0xff, 0x00 },
109 	[STB6100_VCO]		= { 0xff, 0x00 },
110 	[STB6100_NI]		= { 0xff, 0x00 },
111 	[STB6100_NF_LSB]	= { 0xff, 0x00 },
112 	[STB6100_K]		= { 0xc7, 0x38 },
113 	[STB6100_G]		= { 0xef, 0x10 },
114 	[STB6100_F]		= { 0x1f, 0xc0 },
115 	[STB6100_DLB]		= { 0x38, 0xc4 },
116 	[STB6100_TEST1]		= { 0x00, 0x8f },
117 	[STB6100_FCCK]		= { 0x40, 0x0d },
118 	[STB6100_LPEN]		= { 0xf0, 0x0b },
119 	[STB6100_TEST3]		= { 0x00, 0xde },
120 };
121 
122 /*
123  * Currently unused. Some boards might need it in the future
124  */
125 static inline void stb6100_normalise_regs(u8 regs[])
126 {
127 	int i;
128 
129 	for (i = 0; i < STB6100_NUMREGS; i++)
130 		regs[i] = (regs[i] & stb6100_template[i].mask) | stb6100_template[i].set;
131 }
132 
133 static int stb6100_read_regs(struct stb6100_state *state, u8 regs[])
134 {
135 	int rc;
136 	struct i2c_msg msg = {
137 		.addr	= state->config->tuner_address,
138 		.flags	= I2C_M_RD,
139 		.buf	= regs,
140 		.len	= STB6100_NUMREGS
141 	};
142 
143 	rc = i2c_transfer(state->i2c, &msg, 1);
144 	if (unlikely(rc != 1)) {
145 		dprintk(verbose, FE_ERROR, 1, "Read (0x%x) err, rc=[%d]",
146 			state->config->tuner_address, rc);
147 
148 		return -EREMOTEIO;
149 	}
150 	if (unlikely(verbose > FE_DEBUG)) {
151 		int i;
152 
153 		dprintk(verbose, FE_DEBUG, 1, "    Read from 0x%02x", state->config->tuner_address);
154 		for (i = 0; i < STB6100_NUMREGS; i++)
155 			dprintk(verbose, FE_DEBUG, 1, "        %s: 0x%02x", stb6100_regnames[i], regs[i]);
156 	}
157 	return 0;
158 }
159 
160 static int stb6100_read_reg(struct stb6100_state *state, u8 reg)
161 {
162 	u8 regs[STB6100_NUMREGS];
163 
164 	struct i2c_msg msg = {
165 		.addr	= state->config->tuner_address + reg,
166 		.flags	= I2C_M_RD,
167 		.buf	= regs,
168 		.len	= 1
169 	};
170 
171 	i2c_transfer(state->i2c, &msg, 1);
172 
173 	if (unlikely(reg >= STB6100_NUMREGS)) {
174 		dprintk(verbose, FE_ERROR, 1, "Invalid register offset 0x%x", reg);
175 		return -EINVAL;
176 	}
177 	if (unlikely(verbose > FE_DEBUG)) {
178 		dprintk(verbose, FE_DEBUG, 1, "    Read from 0x%02x", state->config->tuner_address);
179 		dprintk(verbose, FE_DEBUG, 1, "        %s: 0x%02x", stb6100_regnames[reg], regs[0]);
180 	}
181 
182 	return (unsigned int)regs[0];
183 }
184 
185 static int stb6100_write_reg_range(struct stb6100_state *state, u8 buf[], int start, int len)
186 {
187 	int rc;
188 	u8 cmdbuf[MAX_XFER_SIZE];
189 	struct i2c_msg msg = {
190 		.addr	= state->config->tuner_address,
191 		.flags	= 0,
192 		.buf	= cmdbuf,
193 		.len	= len + 1
194 	};
195 
196 	if (1 + len > sizeof(cmdbuf)) {
197 		printk(KERN_WARNING
198 		       "%s: i2c wr: len=%d is too big!\n",
199 		       KBUILD_MODNAME, len);
200 		return -EINVAL;
201 	}
202 
203 	if (unlikely(start < 1 || start + len > STB6100_NUMREGS)) {
204 		dprintk(verbose, FE_ERROR, 1, "Invalid register range %d:%d",
205 			start, len);
206 		return -EINVAL;
207 	}
208 	memcpy(&cmdbuf[1], buf, len);
209 	cmdbuf[0] = start;
210 
211 	if (unlikely(verbose > FE_DEBUG)) {
212 		int i;
213 
214 		dprintk(verbose, FE_DEBUG, 1, "    Write @ 0x%02x: [%d:%d]", state->config->tuner_address, start, len);
215 		for (i = 0; i < len; i++)
216 			dprintk(verbose, FE_DEBUG, 1, "        %s: 0x%02x", stb6100_regnames[start + i], buf[i]);
217 	}
218 	rc = i2c_transfer(state->i2c, &msg, 1);
219 	if (unlikely(rc != 1)) {
220 		dprintk(verbose, FE_ERROR, 1, "(0x%x) write err [%d:%d], rc=[%d]",
221 			(unsigned int)state->config->tuner_address, start, len,	rc);
222 		return -EREMOTEIO;
223 	}
224 	return 0;
225 }
226 
227 static int stb6100_write_reg(struct stb6100_state *state, u8 reg, u8 data)
228 {
229 	if (unlikely(reg >= STB6100_NUMREGS)) {
230 		dprintk(verbose, FE_ERROR, 1, "Invalid register offset 0x%x", reg);
231 		return -EREMOTEIO;
232 	}
233 	data = (data & stb6100_template[reg].mask) | stb6100_template[reg].set;
234 	return stb6100_write_reg_range(state, &data, reg, 1);
235 }
236 
237 
238 static int stb6100_get_status(struct dvb_frontend *fe, u32 *status)
239 {
240 	int rc;
241 	struct stb6100_state *state = fe->tuner_priv;
242 
243 	rc = stb6100_read_reg(state, STB6100_LD);
244 	if (rc < 0) {
245 		dprintk(verbose, FE_ERROR, 1, "%s failed", __func__);
246 		return rc;
247 	}
248 	return (rc & STB6100_LD_LOCK) ? TUNER_STATUS_LOCKED : 0;
249 }
250 
251 static int stb6100_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
252 {
253 	int rc;
254 	u8 f;
255 	struct stb6100_state *state = fe->tuner_priv;
256 
257 	rc = stb6100_read_reg(state, STB6100_F);
258 	if (rc < 0)
259 		return rc;
260 	f = rc & STB6100_F_F;
261 
262 	state->status.bandwidth = (f + 5) * 2000;	/* x2 for ZIF	*/
263 
264 	*bandwidth = state->bandwidth = state->status.bandwidth * 1000;
265 	dprintk(verbose, FE_DEBUG, 1, "bandwidth = %u Hz", state->bandwidth);
266 	return 0;
267 }
268 
269 static int stb6100_set_bandwidth(struct dvb_frontend *fe, u32 bandwidth)
270 {
271 	u32 tmp;
272 	int rc;
273 	struct stb6100_state *state = fe->tuner_priv;
274 
275 	dprintk(verbose, FE_DEBUG, 1, "set bandwidth to %u Hz", bandwidth);
276 
277 	bandwidth /= 2; /* ZIF */
278 
279 	if (bandwidth >= 36000000)	/* F[4:0] BW/2 max =31+5=36 mhz for F=31	*/
280 		tmp = 31;
281 	else if (bandwidth <= 5000000)	/* bw/2 min = 5Mhz for F=0			*/
282 		tmp = 0;
283 	else				/* if 5 < bw/2 < 36				*/
284 		tmp = (bandwidth + 500000) / 1000000 - 5;
285 
286 	/* Turn on LPF bandwidth setting clock control,
287 	 * set bandwidth, wait 10ms, turn off.
288 	 */
289 	rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d | STB6100_FCCK_FCCK);
290 	if (rc < 0)
291 		return rc;
292 	rc = stb6100_write_reg(state, STB6100_F, 0xc0 | tmp);
293 	if (rc < 0)
294 		return rc;
295 
296 	msleep(5);  /*  This is dangerous as another (related) thread may start */
297 
298 	rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d);
299 	if (rc < 0)
300 		return rc;
301 
302 	msleep(10);  /*  This is dangerous as another (related) thread may start */
303 
304 	return 0;
305 }
306 
307 static int stb6100_get_frequency(struct dvb_frontend *fe, u32 *frequency)
308 {
309 	int rc;
310 	u32 nint, nfrac, fvco;
311 	int psd2, odiv;
312 	struct stb6100_state *state = fe->tuner_priv;
313 	u8 regs[STB6100_NUMREGS];
314 
315 	rc = stb6100_read_regs(state, regs);
316 	if (rc < 0)
317 		return rc;
318 
319 	odiv = (regs[STB6100_VCO] & STB6100_VCO_ODIV) >> STB6100_VCO_ODIV_SHIFT;
320 	psd2 = (regs[STB6100_K] & STB6100_K_PSD2) >> STB6100_K_PSD2_SHIFT;
321 	nint = regs[STB6100_NI];
322 	nfrac = ((regs[STB6100_K] & STB6100_K_NF_MSB) << 8) | regs[STB6100_NF_LSB];
323 	fvco = (nfrac * state->reference >> (9 - psd2)) + (nint * state->reference << psd2);
324 	*frequency = state->frequency = fvco >> (odiv + 1);
325 
326 	dprintk(verbose, FE_DEBUG, 1,
327 		"frequency = %u kHz, odiv = %u, psd2 = %u, fxtal = %u kHz, fvco = %u kHz, N(I) = %u, N(F) = %u",
328 		state->frequency, odiv, psd2, state->reference,	fvco, nint, nfrac);
329 	return 0;
330 }
331 
332 
333 static int stb6100_set_frequency(struct dvb_frontend *fe, u32 frequency)
334 {
335 	int rc;
336 	const struct stb6100_lkup *ptr;
337 	struct stb6100_state *state = fe->tuner_priv;
338 	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
339 
340 	u32 srate = 0, fvco, nint, nfrac;
341 	u8 regs[STB6100_NUMREGS];
342 	u8 g, psd2, odiv;
343 
344 	dprintk(verbose, FE_DEBUG, 1, "Version 2010-8-14 13:51");
345 
346 	if (fe->ops.get_frontend) {
347 		dprintk(verbose, FE_DEBUG, 1, "Get frontend parameters");
348 		fe->ops.get_frontend(fe);
349 	}
350 	srate = p->symbol_rate;
351 
352 	/* Set up tuner cleanly, LPF calibration on */
353 	rc = stb6100_write_reg(state, STB6100_FCCK, 0x4d | STB6100_FCCK_FCCK);
354 	if (rc < 0)
355 		return rc;  /* allow LPF calibration */
356 
357 	/* PLL Loop disabled, bias on, VCO on, synth on */
358 	regs[STB6100_LPEN] = 0xeb;
359 	rc = stb6100_write_reg(state, STB6100_LPEN, regs[STB6100_LPEN]);
360 	if (rc < 0)
361 		return rc;
362 
363 	/* Program the registers with their data values */
364 
365 	/* VCO divide ratio (LO divide ratio, VCO prescaler enable).	*/
366 	if (frequency <= 1075000)
367 		odiv = 1;
368 	else
369 		odiv = 0;
370 
371 	/* VCO enabled, search clock off as per LL3.7, 3.4.1 */
372 	regs[STB6100_VCO] = 0xe0 | (odiv << STB6100_VCO_ODIV_SHIFT);
373 
374 	/* OSM	*/
375 	for (ptr = lkup;
376 	     (ptr->val_high != 0) && !CHKRANGE(frequency, ptr->val_low, ptr->val_high);
377 	     ptr++);
378 
379 	if (ptr->val_high == 0) {
380 		printk(KERN_ERR "%s: frequency out of range: %u kHz\n", __func__, frequency);
381 		return -EINVAL;
382 	}
383 	regs[STB6100_VCO] = (regs[STB6100_VCO] & ~STB6100_VCO_OSM) | ptr->reg;
384 	rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO]);
385 	if (rc < 0)
386 		return rc;
387 
388 	if ((frequency > 1075000) && (frequency <= 1325000))
389 		psd2 = 0;
390 	else
391 		psd2 = 1;
392 	/* F(VCO) = F(LO) * (ODIV == 0 ? 2 : 4)			*/
393 	fvco = frequency << (1 + odiv);
394 	/* N(I) = floor(f(VCO) / (f(XTAL) * (PSD2 ? 2 : 1)))	*/
395 	nint = fvco / (state->reference << psd2);
396 	/* N(F) = round(f(VCO) / f(XTAL) * (PSD2 ? 2 : 1) - N(I)) * 2 ^ 9	*/
397 	nfrac = DIV_ROUND_CLOSEST((fvco - (nint * state->reference << psd2))
398 					 << (9 - psd2), state->reference);
399 
400 	/* NI */
401 	regs[STB6100_NI] = nint;
402 	rc = stb6100_write_reg(state, STB6100_NI, regs[STB6100_NI]);
403 	if (rc < 0)
404 		return rc;
405 
406 	/* NF */
407 	regs[STB6100_NF_LSB] = nfrac;
408 	rc = stb6100_write_reg(state, STB6100_NF_LSB, regs[STB6100_NF_LSB]);
409 	if (rc < 0)
410 		return rc;
411 
412 	/* K */
413 	regs[STB6100_K] = (0x38 & ~STB6100_K_PSD2) | (psd2 << STB6100_K_PSD2_SHIFT);
414 	regs[STB6100_K] = (regs[STB6100_K] & ~STB6100_K_NF_MSB) | ((nfrac >> 8) & STB6100_K_NF_MSB);
415 	rc = stb6100_write_reg(state, STB6100_K, regs[STB6100_K]);
416 	if (rc < 0)
417 		return rc;
418 
419 	/* G Baseband gain. */
420 	if (srate >= 15000000)
421 		g = 9;  /*  +4 dB */
422 	else if (srate >= 5000000)
423 		g = 11; /*  +8 dB */
424 	else
425 		g = 14; /* +14 dB */
426 
427 	regs[STB6100_G] = (0x10 & ~STB6100_G_G) | g;
428 	regs[STB6100_G] &= ~STB6100_G_GCT; /* mask GCT */
429 	regs[STB6100_G] |= (1 << 5); /* 2Vp-p Mode */
430 	rc = stb6100_write_reg(state, STB6100_G, regs[STB6100_G]);
431 	if (rc < 0)
432 		return rc;
433 
434 	/* F we don't write as it is set up in BW set */
435 
436 	/* DLB set DC servo loop BW to 160Hz (LLA 3.8 / 2.1) */
437 	regs[STB6100_DLB] = 0xcc;
438 	rc = stb6100_write_reg(state, STB6100_DLB, regs[STB6100_DLB]);
439 	if (rc < 0)
440 		return rc;
441 
442 	dprintk(verbose, FE_DEBUG, 1,
443 		"frequency = %u, srate = %u, g = %u, odiv = %u, psd2 = %u, fxtal = %u, osm = %u, fvco = %u, N(I) = %u, N(F) = %u",
444 		frequency, srate, (unsigned int)g, (unsigned int)odiv,
445 		(unsigned int)psd2, state->reference,
446 		ptr->reg, fvco, nint, nfrac);
447 
448 	/* Set up the test registers */
449 	regs[STB6100_TEST1] = 0x8f;
450 	rc = stb6100_write_reg(state, STB6100_TEST1, regs[STB6100_TEST1]);
451 	if (rc < 0)
452 		return rc;
453 	regs[STB6100_TEST3] = 0xde;
454 	rc = stb6100_write_reg(state, STB6100_TEST3, regs[STB6100_TEST3]);
455 	if (rc < 0)
456 		return rc;
457 
458 	/* Bring up tuner according to LLA 3.7 3.4.1, step 2 */
459 	regs[STB6100_LPEN] = 0xfb; /* PLL Loop enabled, bias on, VCO on, synth on */
460 	rc = stb6100_write_reg(state, STB6100_LPEN, regs[STB6100_LPEN]);
461 	if (rc < 0)
462 		return rc;
463 
464 	msleep(2);
465 
466 	/* Bring up tuner according to LLA 3.7 3.4.1, step 3 */
467 	regs[STB6100_VCO] &= ~STB6100_VCO_OCK;		/* VCO fast search		*/
468 	rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO]);
469 	if (rc < 0)
470 		return rc;
471 
472 	msleep(10);  /*  This is dangerous as another (related) thread may start */ /* wait for LO to lock */
473 
474 	regs[STB6100_VCO] &= ~STB6100_VCO_OSCH;		/* vco search disabled		*/
475 	regs[STB6100_VCO] |= STB6100_VCO_OCK;		/* search clock off		*/
476 	rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO]);
477 	if (rc < 0)
478 		return rc;
479 
480 	rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d);
481 	if (rc < 0)
482 		return rc;  /* Stop LPF calibration */
483 
484 	msleep(10);  /*  This is dangerous as another (related) thread may start */
485 		     /* wait for stabilisation, (should not be necessary)		*/
486 	return 0;
487 }
488 
489 static int stb6100_sleep(struct dvb_frontend *fe)
490 {
491 	/* TODO: power down	*/
492 	return 0;
493 }
494 
495 static int stb6100_init(struct dvb_frontend *fe)
496 {
497 	struct stb6100_state *state = fe->tuner_priv;
498 	struct tuner_state *status = &state->status;
499 
500 	status->tunerstep	= 125000;
501 	status->ifreq		= 0;
502 	status->refclock	= 27000000;	/* Hz	*/
503 	status->iqsense		= 1;
504 	status->bandwidth	= 36000;	/* kHz	*/
505 	state->bandwidth	= status->bandwidth * 1000;	/* Hz	*/
506 	state->reference	= status->refclock / 1000;	/* kHz	*/
507 
508 	/* Set default bandwidth. Modified, PN 13-May-10	*/
509 	return 0;
510 }
511 
512 static int stb6100_get_state(struct dvb_frontend *fe,
513 			     enum tuner_param param,
514 			     struct tuner_state *state)
515 {
516 	switch (param) {
517 	case DVBFE_TUNER_FREQUENCY:
518 		stb6100_get_frequency(fe, &state->frequency);
519 		break;
520 	case DVBFE_TUNER_TUNERSTEP:
521 		break;
522 	case DVBFE_TUNER_IFFREQ:
523 		break;
524 	case DVBFE_TUNER_BANDWIDTH:
525 		stb6100_get_bandwidth(fe, &state->bandwidth);
526 		break;
527 	case DVBFE_TUNER_REFCLOCK:
528 		break;
529 	default:
530 		break;
531 	}
532 
533 	return 0;
534 }
535 
536 static int stb6100_set_state(struct dvb_frontend *fe,
537 			     enum tuner_param param,
538 			     struct tuner_state *state)
539 {
540 	struct stb6100_state *tstate = fe->tuner_priv;
541 
542 	switch (param) {
543 	case DVBFE_TUNER_FREQUENCY:
544 		stb6100_set_frequency(fe, state->frequency);
545 		tstate->frequency = state->frequency;
546 		break;
547 	case DVBFE_TUNER_TUNERSTEP:
548 		break;
549 	case DVBFE_TUNER_IFFREQ:
550 		break;
551 	case DVBFE_TUNER_BANDWIDTH:
552 		stb6100_set_bandwidth(fe, state->bandwidth);
553 		tstate->bandwidth = state->bandwidth;
554 		break;
555 	case DVBFE_TUNER_REFCLOCK:
556 		break;
557 	default:
558 		break;
559 	}
560 
561 	return 0;
562 }
563 
564 static struct dvb_tuner_ops stb6100_ops = {
565 	.info = {
566 		.name			= "STB6100 Silicon Tuner",
567 		.frequency_min		= 950000,
568 		.frequency_max		= 2150000,
569 		.frequency_step		= 0,
570 	},
571 
572 	.init		= stb6100_init,
573 	.sleep          = stb6100_sleep,
574 	.get_status	= stb6100_get_status,
575 	.get_state	= stb6100_get_state,
576 	.set_state	= stb6100_set_state,
577 	.release	= stb6100_release
578 };
579 
580 struct dvb_frontend *stb6100_attach(struct dvb_frontend *fe,
581 				    const struct stb6100_config *config,
582 				    struct i2c_adapter *i2c)
583 {
584 	struct stb6100_state *state = NULL;
585 
586 	state = kzalloc(sizeof (struct stb6100_state), GFP_KERNEL);
587 	if (!state)
588 		return NULL;
589 
590 	state->config		= config;
591 	state->i2c		= i2c;
592 	state->frontend		= fe;
593 	state->reference	= config->refclock / 1000; /* kHz */
594 	fe->tuner_priv		= state;
595 	fe->ops.tuner_ops	= stb6100_ops;
596 
597 	printk("%s: Attaching STB6100 \n", __func__);
598 	return fe;
599 }
600 
601 static int stb6100_release(struct dvb_frontend *fe)
602 {
603 	struct stb6100_state *state = fe->tuner_priv;
604 
605 	fe->tuner_priv = NULL;
606 	kfree(state);
607 
608 	return 0;
609 }
610 
611 EXPORT_SYMBOL(stb6100_attach);
612 MODULE_PARM_DESC(verbose, "Set Verbosity level");
613 
614 MODULE_AUTHOR("Manu Abraham");
615 MODULE_DESCRIPTION("STB6100 Silicon tuner");
616 MODULE_LICENSE("GPL");
617