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
24struct 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
33static int debug;
34#define dprintk(args...) \
35	do { \
36		if (debug) printk(KERN_DEBUG "sp887x: " args); \
37	} while (0)
38
39static 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
53static 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
76static 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
92static 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
102static 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
112static 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 */
137static 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
212static 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 */
287static 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
305static 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
349static 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
419static 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
453static 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
467static 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
478static 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
488static 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
499static 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
510static 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
520static 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
551static 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
559static void sp887x_release(struct dvb_frontend* fe)
560{
561	struct sp887x_state* state = fe->demodulator_priv;
562	kfree(state);
563}
564
565static struct dvb_frontend_ops sp887x_ops;
566
567struct 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
589error:
590	kfree(state);
591	return NULL;
592}
593
594static 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
623module_param(debug, int, 0644);
624MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
625
626MODULE_DESCRIPTION("Spase sp887x DVB-T demodulator driver");
627MODULE_LICENSE("GPL");
628
629EXPORT_SYMBOL(sp887x_attach);
630