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