1 /*
2    Driver for the Spase sp887x demodulator
3 */
4 
5 /*
6  * This driver needs external firmware. Please use the command
7  * "<kerneldir>/Documentation/dvb/get_dvb_firmware sp887x" to
8  * download/extract it, and then copy it to /usr/lib/hotplug/firmware
9  * or /lib/firmware (depending on configuration of firmware hotplug).
10  */
11 #define SP887X_DEFAULT_FIRMWARE "dvb-fe-sp887x.fw"
12 
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/device.h>
16 #include <linux/firmware.h>
17 #include <linux/string.h>
18 #include <linux/slab.h>
19 
20 #include "dvb_frontend.h"
21 #include "sp887x.h"
22 
23 
24 struct sp887x_state {
25 	struct i2c_adapter* i2c;
26 	const struct sp887x_config* config;
27 	struct dvb_frontend frontend;
28 
29 	/* demodulator private data */
30 	u8 initialised:1;
31 };
32 
33 static int debug;
34 #define dprintk(args...) \
35 	do { \
36 		if (debug) printk(KERN_DEBUG "sp887x: " args); \
37 	} while (0)
38 
39 static int i2c_writebytes (struct sp887x_state* state, u8 *buf, u8 len)
40 {
41 	struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = len };
42 	int err;
43 
44 	if ((err = i2c_transfer (state->i2c, &msg, 1)) != 1) {
45 		printk ("%s: i2c write error (addr %02x, err == %i)\n",
46 			__func__, state->config->demod_address, err);
47 		return -EREMOTEIO;
48 	}
49 
50 	return 0;
51 }
52 
53 static int sp887x_writereg (struct sp887x_state* state, u16 reg, u16 data)
54 {
55 	u8 b0 [] = { reg >> 8 , reg & 0xff, data >> 8, data & 0xff };
56 	struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 4 };
57 	int ret;
58 
59 	if ((ret = i2c_transfer(state->i2c, &msg, 1)) != 1) {
60 		/**
61 		 *  in case of soft reset we ignore ACK errors...
62 		 */
63 		if (!(reg == 0xf1a && data == 0x000 &&
64 			(ret == -EREMOTEIO || ret == -EFAULT)))
65 		{
66 			printk("%s: writereg error "
67 			       "(reg %03x, data %03x, ret == %i)\n",
68 			       __func__, reg & 0xffff, data & 0xffff, ret);
69 			return ret;
70 		}
71 	}
72 
73 	return 0;
74 }
75 
76 static int sp887x_readreg (struct sp887x_state* state, u16 reg)
77 {
78 	u8 b0 [] = { reg >> 8 , reg & 0xff };
79 	u8 b1 [2];
80 	int ret;
81 	struct i2c_msg msg[] = {{ .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 2 },
82 			 { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 2 }};
83 
84 	if ((ret = i2c_transfer(state->i2c, msg, 2)) != 2) {
85 		printk("%s: readreg error (ret == %i)\n", __func__, ret);
86 		return -1;
87 	}
88 
89 	return (((b1[0] << 8) | b1[1]) & 0xfff);
90 }
91 
92 static void sp887x_microcontroller_stop (struct sp887x_state* state)
93 {
94 	dprintk("%s\n", __func__);
95 	sp887x_writereg(state, 0xf08, 0x000);
96 	sp887x_writereg(state, 0xf09, 0x000);
97 
98 	/* microcontroller STOP */
99 	sp887x_writereg(state, 0xf00, 0x000);
100 }
101 
102 static void sp887x_microcontroller_start (struct sp887x_state* state)
103 {
104 	dprintk("%s\n", __func__);
105 	sp887x_writereg(state, 0xf08, 0x000);
106 	sp887x_writereg(state, 0xf09, 0x000);
107 
108 	/* microcontroller START */
109 	sp887x_writereg(state, 0xf00, 0x001);
110 }
111 
112 static void sp887x_setup_agc (struct sp887x_state* state)
113 {
114 	/* setup AGC parameters */
115 	dprintk("%s\n", __func__);
116 	sp887x_writereg(state, 0x33c, 0x054);
117 	sp887x_writereg(state, 0x33b, 0x04c);
118 	sp887x_writereg(state, 0x328, 0x000);
119 	sp887x_writereg(state, 0x327, 0x005);
120 	sp887x_writereg(state, 0x326, 0x001);
121 	sp887x_writereg(state, 0x325, 0x001);
122 	sp887x_writereg(state, 0x324, 0x001);
123 	sp887x_writereg(state, 0x318, 0x050);
124 	sp887x_writereg(state, 0x317, 0x3fe);
125 	sp887x_writereg(state, 0x316, 0x001);
126 	sp887x_writereg(state, 0x313, 0x005);
127 	sp887x_writereg(state, 0x312, 0x002);
128 	sp887x_writereg(state, 0x306, 0x000);
129 	sp887x_writereg(state, 0x303, 0x000);
130 }
131 
132 #define BLOCKSIZE 30
133 #define FW_SIZE 0x4000
134 /**
135  *  load firmware and setup MPEG interface...
136  */
137 static int sp887x_initial_setup (struct dvb_frontend* fe, const struct firmware *fw)
138 {
139 	struct sp887x_state* state = fe->demodulator_priv;
140 	u8 buf [BLOCKSIZE+2];
141 	int i;
142 	int fw_size = fw->size;
143 	const unsigned char *mem = fw->data;
144 
145 	dprintk("%s\n", __func__);
146 
147 	/* ignore the first 10 bytes, then we expect 0x4000 bytes of firmware */
148 	if (fw_size < FW_SIZE+10)
149 		return -ENODEV;
150 
151 	mem = fw->data + 10;
152 
153 	/* soft reset */
154 	sp887x_writereg(state, 0xf1a, 0x000);
155 
156 	sp887x_microcontroller_stop (state);
157 
158 	printk ("%s: firmware upload... ", __func__);
159 
160 	/* setup write pointer to -1 (end of memory) */
161 	/* bit 0x8000 in address is set to enable 13bit mode */
162 	sp887x_writereg(state, 0x8f08, 0x1fff);
163 
164 	/* dummy write (wrap around to start of memory) */
165 	sp887x_writereg(state, 0x8f0a, 0x0000);
166 
167 	for (i = 0; i < FW_SIZE; i += BLOCKSIZE) {
168 		int c = BLOCKSIZE;
169 		int err;
170 
171 		if (i+c > FW_SIZE)
172 			c = FW_SIZE - i;
173 
174 		/* bit 0x8000 in address is set to enable 13bit mode */
175 		/* bit 0x4000 enables multibyte read/write transfers */
176 		/* write register is 0xf0a */
177 		buf[0] = 0xcf;
178 		buf[1] = 0x0a;
179 
180 		memcpy(&buf[2], mem + i, c);
181 
182 		if ((err = i2c_writebytes (state, buf, c+2)) < 0) {
183 			printk ("failed.\n");
184 			printk ("%s: i2c error (err == %i)\n", __func__, err);
185 			return err;
186 		}
187 	}
188 
189 	/* don't write RS bytes between packets */
190 	sp887x_writereg(state, 0xc13, 0x001);
191 
192 	/* suppress clock if (!data_valid) */
193 	sp887x_writereg(state, 0xc14, 0x000);
194 
195 	/* setup MPEG interface... */
196 	sp887x_writereg(state, 0xc1a, 0x872);
197 	sp887x_writereg(state, 0xc1b, 0x001);
198 	sp887x_writereg(state, 0xc1c, 0x000); /* parallel mode (serial mode == 1) */
199 	sp887x_writereg(state, 0xc1a, 0x871);
200 
201 	/* ADC mode, 2 for MT8872, 3 for SP8870/SP8871 */
202 	sp887x_writereg(state, 0x301, 0x002);
203 
204 	sp887x_setup_agc(state);
205 
206 	/* bit 0x010: enable data valid signal */
207 	sp887x_writereg(state, 0xd00, 0x010);
208 	sp887x_writereg(state, 0x0d1, 0x000);
209 	return 0;
210 };
211 
212 static int configure_reg0xc05(struct dtv_frontend_properties *p, u16 *reg0xc05)
213 {
214 	int known_parameters = 1;
215 
216 	*reg0xc05 = 0x000;
217 
218 	switch (p->modulation) {
219 	case QPSK:
220 		break;
221 	case QAM_16:
222 		*reg0xc05 |= (1 << 10);
223 		break;
224 	case QAM_64:
225 		*reg0xc05 |= (2 << 10);
226 		break;
227 	case QAM_AUTO:
228 		known_parameters = 0;
229 		break;
230 	default:
231 		return -EINVAL;
232 	}
233 
234 	switch (p->hierarchy) {
235 	case HIERARCHY_NONE:
236 		break;
237 	case HIERARCHY_1:
238 		*reg0xc05 |= (1 << 7);
239 		break;
240 	case HIERARCHY_2:
241 		*reg0xc05 |= (2 << 7);
242 		break;
243 	case HIERARCHY_4:
244 		*reg0xc05 |= (3 << 7);
245 		break;
246 	case HIERARCHY_AUTO:
247 		known_parameters = 0;
248 		break;
249 	default:
250 		return -EINVAL;
251 	}
252 
253 	switch (p->code_rate_HP) {
254 	case FEC_1_2:
255 		break;
256 	case FEC_2_3:
257 		*reg0xc05 |= (1 << 3);
258 		break;
259 	case FEC_3_4:
260 		*reg0xc05 |= (2 << 3);
261 		break;
262 	case FEC_5_6:
263 		*reg0xc05 |= (3 << 3);
264 		break;
265 	case FEC_7_8:
266 		*reg0xc05 |= (4 << 3);
267 		break;
268 	case FEC_AUTO:
269 		known_parameters = 0;
270 		break;
271 	default:
272 		return -EINVAL;
273 	}
274 
275 	if (known_parameters)
276 		*reg0xc05 |= (2 << 1);	/* use specified parameters */
277 	else
278 		*reg0xc05 |= (1 << 1);	/* enable autoprobing */
279 
280 	return 0;
281 }
282 
283 /**
284  *  estimates division of two 24bit numbers,
285  *  derived from the ves1820/stv0299 driver code
286  */
287 static void divide (int n, int d, int *quotient_i, int *quotient_f)
288 {
289 	unsigned int q, r;
290 
291 	r = (n % d) << 8;
292 	q = (r / d);
293 
294 	if (quotient_i)
295 		*quotient_i = q;
296 
297 	if (quotient_f) {
298 		r = (r % d) << 8;
299 		q = (q << 8) | (r / d);
300 		r = (r % d) << 8;
301 		*quotient_f = (q << 8) | (r / d);
302 	}
303 }
304 
305 static void sp887x_correct_offsets (struct sp887x_state* state,
306 				    struct dtv_frontend_properties *p,
307 				    int actual_freq)
308 {
309 	static const u32 srate_correction [] = { 1879617, 4544878, 8098561 };
310 	int bw_index;
311 	int freq_offset = actual_freq - p->frequency;
312 	int sysclock = 61003; //[kHz]
313 	int ifreq = 36000000;
314 	int freq;
315 	int frequency_shift;
316 
317 	switch (p->bandwidth_hz) {
318 	default:
319 	case 8000000:
320 		bw_index = 0;
321 		break;
322 	case 7000000:
323 		bw_index = 1;
324 		break;
325 	case 6000000:
326 		bw_index = 2;
327 		break;
328 	}
329 
330 	if (p->inversion == INVERSION_ON)
331 		freq = ifreq - freq_offset;
332 	else
333 		freq = ifreq + freq_offset;
334 
335 	divide(freq / 333, sysclock, NULL, &frequency_shift);
336 
337 	if (p->inversion == INVERSION_ON)
338 		frequency_shift = -frequency_shift;
339 
340 	/* sample rate correction */
341 	sp887x_writereg(state, 0x319, srate_correction[bw_index] >> 12);
342 	sp887x_writereg(state, 0x31a, srate_correction[bw_index] & 0xfff);
343 
344 	/* carrier offset correction */
345 	sp887x_writereg(state, 0x309, frequency_shift >> 12);
346 	sp887x_writereg(state, 0x30a, frequency_shift & 0xfff);
347 }
348 
349 static int sp887x_setup_frontend_parameters(struct dvb_frontend *fe)
350 {
351 	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
352 	struct sp887x_state* state = fe->demodulator_priv;
353 	unsigned actual_freq;
354 	int err;
355 	u16 val, reg0xc05;
356 
357 	if (p->bandwidth_hz != 8000000 &&
358 	    p->bandwidth_hz != 7000000 &&
359 	    p->bandwidth_hz != 6000000)
360 		return -EINVAL;
361 
362 	if ((err = configure_reg0xc05(p, &reg0xc05)))
363 		return err;
364 
365 	sp887x_microcontroller_stop(state);
366 
367 	/* setup the PLL */
368 	if (fe->ops.tuner_ops.set_params) {
369 		fe->ops.tuner_ops.set_params(fe);
370 		if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
371 	}
372 	if (fe->ops.tuner_ops.get_frequency) {
373 		fe->ops.tuner_ops.get_frequency(fe, &actual_freq);
374 		if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
375 	} else {
376 		actual_freq = p->frequency;
377 	}
378 
379 	/* read status reg in order to clear <pending irqs */
380 	sp887x_readreg(state, 0x200);
381 
382 	sp887x_correct_offsets(state, p, actual_freq);
383 
384 	/* filter for 6/7/8 Mhz channel */
385 	if (p->bandwidth_hz == 6000000)
386 		val = 2;
387 	else if (p->bandwidth_hz == 7000000)
388 		val = 1;
389 	else
390 		val = 0;
391 
392 	sp887x_writereg(state, 0x311, val);
393 
394 	/* scan order: 2k first = 0, 8k first = 1 */
395 	if (p->transmission_mode == TRANSMISSION_MODE_2K)
396 		sp887x_writereg(state, 0x338, 0x000);
397 	else
398 		sp887x_writereg(state, 0x338, 0x001);
399 
400 	sp887x_writereg(state, 0xc05, reg0xc05);
401 
402 	if (p->bandwidth_hz == 6000000)
403 		val = 2 << 3;
404 	else if (p->bandwidth_hz == 7000000)
405 		val = 3 << 3;
406 	else
407 		val = 0 << 3;
408 
409 	/* enable OFDM and SAW bits as lock indicators in sync register 0xf17,
410 	 * optimize algorithm for given bandwidth...
411 	 */
412 	sp887x_writereg(state, 0xf14, 0x160 | val);
413 	sp887x_writereg(state, 0xf15, 0x000);
414 
415 	sp887x_microcontroller_start(state);
416 	return 0;
417 }
418 
419 static int sp887x_read_status(struct dvb_frontend *fe, enum fe_status *status)
420 {
421 	struct sp887x_state* state = fe->demodulator_priv;
422 	u16 snr12 = sp887x_readreg(state, 0xf16);
423 	u16 sync0x200 = sp887x_readreg(state, 0x200);
424 	u16 sync0xf17 = sp887x_readreg(state, 0xf17);
425 
426 	*status = 0;
427 
428 	if (snr12 > 0x00f)
429 		*status |= FE_HAS_SIGNAL;
430 
431 	//if (sync0x200 & 0x004)
432 	//	*status |= FE_HAS_SYNC | FE_HAS_CARRIER;
433 
434 	//if (sync0x200 & 0x008)
435 	//	*status |= FE_HAS_VITERBI;
436 
437 	if ((sync0xf17 & 0x00f) == 0x002) {
438 		*status |= FE_HAS_LOCK;
439 		*status |= FE_HAS_VITERBI | FE_HAS_SYNC | FE_HAS_CARRIER;
440 	}
441 
442 	if (sync0x200 & 0x001) {	/* tuner adjustment requested...*/
443 		int steps = (sync0x200 >> 4) & 0x00f;
444 		if (steps & 0x008)
445 			steps = -steps;
446 		dprintk("sp887x: implement tuner adjustment (%+i steps)!!\n",
447 		       steps);
448 	}
449 
450 	return 0;
451 }
452 
453 static int sp887x_read_ber(struct dvb_frontend* fe, u32* ber)
454 {
455 	struct sp887x_state* state = fe->demodulator_priv;
456 
457 	*ber = (sp887x_readreg(state, 0xc08) & 0x3f) |
458 	       (sp887x_readreg(state, 0xc07) << 6);
459 	sp887x_writereg(state, 0xc08, 0x000);
460 	sp887x_writereg(state, 0xc07, 0x000);
461 	if (*ber >= 0x3fff0)
462 		*ber = ~0;
463 
464 	return 0;
465 }
466 
467 static int sp887x_read_signal_strength(struct dvb_frontend* fe, u16* strength)
468 {
469 	struct sp887x_state* state = fe->demodulator_priv;
470 
471 	u16 snr12 = sp887x_readreg(state, 0xf16);
472 	u32 signal = 3 * (snr12 << 4);
473 	*strength = (signal < 0xffff) ? signal : 0xffff;
474 
475 	return 0;
476 }
477 
478 static int sp887x_read_snr(struct dvb_frontend* fe, u16* snr)
479 {
480 	struct sp887x_state* state = fe->demodulator_priv;
481 
482 	u16 snr12 = sp887x_readreg(state, 0xf16);
483 	*snr = (snr12 << 4) | (snr12 >> 8);
484 
485 	return 0;
486 }
487 
488 static int sp887x_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
489 {
490 	struct sp887x_state* state = fe->demodulator_priv;
491 
492 	*ucblocks = sp887x_readreg(state, 0xc0c);
493 	if (*ucblocks == 0xfff)
494 		*ucblocks = ~0;
495 
496 	return 0;
497 }
498 
499 static int sp887x_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
500 {
501 	struct sp887x_state* state = fe->demodulator_priv;
502 
503 	if (enable) {
504 		return sp887x_writereg(state, 0x206, 0x001);
505 	} else {
506 		return sp887x_writereg(state, 0x206, 0x000);
507 	}
508 }
509 
510 static int sp887x_sleep(struct dvb_frontend* fe)
511 {
512 	struct sp887x_state* state = fe->demodulator_priv;
513 
514 	/* tristate TS output and disable interface pins */
515 	sp887x_writereg(state, 0xc18, 0x000);
516 
517 	return 0;
518 }
519 
520 static int sp887x_init(struct dvb_frontend* fe)
521 {
522 	struct sp887x_state* state = fe->demodulator_priv;
523 	const struct firmware *fw = NULL;
524 	int ret;
525 
526 	if (!state->initialised) {
527 		/* request the firmware, this will block until someone uploads it */
528 		printk("sp887x: waiting for firmware upload (%s)...\n", SP887X_DEFAULT_FIRMWARE);
529 		ret = state->config->request_firmware(fe, &fw, SP887X_DEFAULT_FIRMWARE);
530 		if (ret) {
531 			printk("sp887x: no firmware upload (timeout or file not found?)\n");
532 			return ret;
533 		}
534 
535 		ret = sp887x_initial_setup(fe, fw);
536 		release_firmware(fw);
537 		if (ret) {
538 			printk("sp887x: writing firmware to device failed\n");
539 			return ret;
540 		}
541 		printk("sp887x: firmware upload complete\n");
542 		state->initialised = 1;
543 	}
544 
545 	/* enable TS output and interface pins */
546 	sp887x_writereg(state, 0xc18, 0x00d);
547 
548 	return 0;
549 }
550 
551 static int sp887x_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fesettings)
552 {
553 	fesettings->min_delay_ms = 350;
554 	fesettings->step_size = 166666*2;
555 	fesettings->max_drift = (166666*2)+1;
556 	return 0;
557 }
558 
559 static void sp887x_release(struct dvb_frontend* fe)
560 {
561 	struct sp887x_state* state = fe->demodulator_priv;
562 	kfree(state);
563 }
564 
565 static struct dvb_frontend_ops sp887x_ops;
566 
567 struct dvb_frontend* sp887x_attach(const struct sp887x_config* config,
568 				   struct i2c_adapter* i2c)
569 {
570 	struct sp887x_state* state = NULL;
571 
572 	/* allocate memory for the internal state */
573 	state = kzalloc(sizeof(struct sp887x_state), GFP_KERNEL);
574 	if (state == NULL) goto error;
575 
576 	/* setup the state */
577 	state->config = config;
578 	state->i2c = i2c;
579 	state->initialised = 0;
580 
581 	/* check if the demod is there */
582 	if (sp887x_readreg(state, 0x0200) < 0) goto error;
583 
584 	/* create dvb_frontend */
585 	memcpy(&state->frontend.ops, &sp887x_ops, sizeof(struct dvb_frontend_ops));
586 	state->frontend.demodulator_priv = state;
587 	return &state->frontend;
588 
589 error:
590 	kfree(state);
591 	return NULL;
592 }
593 
594 static struct dvb_frontend_ops sp887x_ops = {
595 	.delsys = { SYS_DVBT },
596 	.info = {
597 		.name = "Spase SP887x DVB-T",
598 		.frequency_min =  50500000,
599 		.frequency_max = 858000000,
600 		.frequency_stepsize = 166666,
601 		.caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
602 			FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
603 			FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
604 			FE_CAN_RECOVER
605 	},
606 
607 	.release = sp887x_release,
608 
609 	.init = sp887x_init,
610 	.sleep = sp887x_sleep,
611 	.i2c_gate_ctrl = sp887x_i2c_gate_ctrl,
612 
613 	.set_frontend = sp887x_setup_frontend_parameters,
614 	.get_tune_settings = sp887x_get_tune_settings,
615 
616 	.read_status = sp887x_read_status,
617 	.read_ber = sp887x_read_ber,
618 	.read_signal_strength = sp887x_read_signal_strength,
619 	.read_snr = sp887x_read_snr,
620 	.read_ucblocks = sp887x_read_ucblocks,
621 };
622 
623 module_param(debug, int, 0644);
624 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
625 
626 MODULE_DESCRIPTION("Spase sp887x DVB-T demodulator driver");
627 MODULE_LICENSE("GPL");
628 
629 EXPORT_SYMBOL(sp887x_attach);
630