sp8870.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Driver for Spase SP8870 demodulator
  4.*
  5 *  Copyright (C) 1999 Juergen Peitz
  6 */
  7
  8/*
  9 * This driver needs external firmware. Please use the command
 10 * "<kerneldir>/scripts/get_dvb_firmware alps_tdlb7" to
 11 * download/extract it, and then copy it to /usr/lib/hotplug/firmware
 12 * or /lib/firmware (depending on configuration of firmware hotplug).
 13 */
 14
 15#ifdef pr_fmt
 16#undef pr_fmt
 17#endif
 18#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 19
 20#define SP8870_DEFAULT_FIRMWARE "dvb-fe-sp8870.fw"
 21
 22#include <linux/init.h>
 23#include <linux/module.h>
 24#include <linux/device.h>
 25#include <linux/firmware.h>
 26#include <linux/delay.h>
 27#include <linux/string.h>
 28#include <linux/slab.h>
 29
 30#include <media/dvb_frontend.h>
 31#include "sp8870.h"
 32
 33struct sp8870_state {
 34	struct i2c_adapter *i2c;
 35
 36	const struct sp8870_config *config;
 37
 38	struct dvb_frontend frontend;
 39
 40	/* demodulator private data */
 41	u8 initialised:1;
 42};
 43
 44static int debug;
 45#define dprintk(fmt, arg...) \
 46	do { \
 47		if (debug) \
 48			pr_info("%s(): " fmt, __func__, ##arg); \
 49	} while (0)
 50
 51/* firmware size for sp8870 */
 52#define SP8870_FIRMWARE_SIZE 16382
 53
 54/* starting point for firmware in file 'Sc_main.mc' */
 55#define SP8870_FIRMWARE_OFFSET 0x0A
 56
 57static int sp8870_writereg(struct sp8870_state *state, u16 reg, u16 data)
 58{
 59	u8 buf[] = { reg >> 8, reg & 0xff, data >> 8, data & 0xff };
 60	struct i2c_msg msg = {
 61		.addr = state->config->demod_address,
 62		.flags = 0,
 63		.buf = buf,
 64		.len = 4
 65	};
 66
 67	int err;
 68
 69	err = i2c_transfer(state->i2c, &msg, 1);
 70	if (err != 1) {
 71		dprintk("writereg error (err == %i, reg == 0x%02x, data == 0x%02x)\n", err, reg, data);
 72		return -EREMOTEIO;
 73	}
 74
 75	return 0;
 76}
 77
 78static int sp8870_readreg(struct sp8870_state *state, u16 reg)
 79{
 80	int ret;
 81	u8 b0[] = { reg >> 8, reg & 0xff };
 82	u8 b1[] = { 0, 0 };
 83	struct i2c_msg msg[] = {
 84		{ .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 2 },
 85		{ .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 2 }
 86	};
 87
 88	ret = i2c_transfer(state->i2c, msg, 2);
 89
 90	if (ret != 2) {
 91		dprintk("readreg error (ret == %i)\n", ret);
 92		return -1;
 93	}
 94
 95	return (b1[0] << 8 | b1[1]);
 96}
 97
 98static int sp8870_firmware_upload(struct sp8870_state *state, const struct firmware *fw)
 99{
100	struct i2c_msg msg;
101	const char *fw_buf = fw->data;
102	int fw_pos;
103	u8 tx_buf[255];
104	int tx_len;
105	int err = 0;
106
107	dprintk("start firmware upload...\n");
108
109	if (fw->size < SP8870_FIRMWARE_SIZE + SP8870_FIRMWARE_OFFSET)
110		return -EINVAL;
111
112	// system controller stop
113	sp8870_writereg(state, 0x0F00, 0x0000);
114
115	// instruction RAM register hiword
116	sp8870_writereg(state, 0x8F08, ((SP8870_FIRMWARE_SIZE / 2) & 0xFFFF));
117
118	// instruction RAM MWR
119	sp8870_writereg(state, 0x8F0A, ((SP8870_FIRMWARE_SIZE / 2) >> 16));
120
121	// do firmware upload
122	fw_pos = SP8870_FIRMWARE_OFFSET;
123	while (fw_pos < SP8870_FIRMWARE_SIZE + SP8870_FIRMWARE_OFFSET) {
124		tx_len = (fw_pos <= SP8870_FIRMWARE_SIZE + SP8870_FIRMWARE_OFFSET - 252) ? 252 :
125			 SP8870_FIRMWARE_SIZE + SP8870_FIRMWARE_OFFSET - fw_pos;
126		// write register 0xCF0A
127		tx_buf[0] = 0xCF;
128		tx_buf[1] = 0x0A;
129		memcpy(&tx_buf[2], fw_buf + fw_pos, tx_len);
130		msg.addr = state->config->demod_address;
131		msg.flags = 0;
132		msg.buf = tx_buf;
133		msg.len = tx_len + 2;
134		err = i2c_transfer(state->i2c, &msg, 1);
135		if (err != 1) {
136			pr_err("%s(): firmware upload failed!\n", __func__);
137			pr_err("%s(): i2c error (err == %i)\n", __func__, err);
138			return err;
139		}
140		fw_pos += tx_len;
141	}
142
143	dprintk("firmware upload successful!\n");
144	return 0;
145};
146
147static void sp8870_microcontroller_stop(struct sp8870_state *state)
148{
149	sp8870_writereg(state, 0x0F08, 0x000);
150	sp8870_writereg(state, 0x0F09, 0x000);
151
152	// microcontroller STOP
153	sp8870_writereg(state, 0x0F00, 0x000);
154}
155
156static void sp8870_microcontroller_start(struct sp8870_state *state)
157{
158	sp8870_writereg(state, 0x0F08, 0x000);
159	sp8870_writereg(state, 0x0F09, 0x000);
160
161	// microcontroller START
162	sp8870_writereg(state, 0x0F00, 0x001);
163	// not documented but if we don't read 0x0D01 out here
164	// we don't get a correct data valid signal
165	sp8870_readreg(state, 0x0D01);
166}
167
168static int sp8870_read_data_valid_signal(struct sp8870_state *state)
169{
170	return (sp8870_readreg(state, 0x0D02) > 0);
171}
172
173static int configure_reg0xc05(struct dtv_frontend_properties *p, u16 *reg0xc05)
174{
175	int known_parameters = 1;
176
177	*reg0xc05 = 0x000;
178
179	switch (p->modulation) {
180	case QPSK:
181		break;
182	case QAM_16:
183		*reg0xc05 |= (1 << 10);
184		break;
185	case QAM_64:
186		*reg0xc05 |= (2 << 10);
187		break;
188	case QAM_AUTO:
189		known_parameters = 0;
190		break;
191	default:
192		return -EINVAL;
193	}
194
195	switch (p->hierarchy) {
196	case HIERARCHY_NONE:
197		break;
198	case HIERARCHY_1:
199		*reg0xc05 |= (1 << 7);
200		break;
201	case HIERARCHY_2:
202		*reg0xc05 |= (2 << 7);
203		break;
204	case HIERARCHY_4:
205		*reg0xc05 |= (3 << 7);
206		break;
207	case HIERARCHY_AUTO:
208		known_parameters = 0;
209		break;
210	default:
211		return -EINVAL;
212	}
213
214	switch (p->code_rate_HP) {
215	case FEC_1_2:
216		break;
217	case FEC_2_3:
218		*reg0xc05 |= (1 << 3);
219		break;
220	case FEC_3_4:
221		*reg0xc05 |= (2 << 3);
222		break;
223	case FEC_5_6:
224		*reg0xc05 |= (3 << 3);
225		break;
226	case FEC_7_8:
227		*reg0xc05 |= (4 << 3);
228		break;
229	case FEC_AUTO:
230		known_parameters = 0;
231		break;
232	default:
233		return -EINVAL;
234	}
235
236	if (known_parameters)
237		*reg0xc05 |= (2 << 1);	/* use specified parameters */
238	else
239		*reg0xc05 |= (1 << 1);	/* enable autoprobing */
240
241	return 0;
242}
243
244static int sp8870_wake_up(struct sp8870_state *state)
245{
246	// enable TS output and interface pins
247	return sp8870_writereg(state, 0xC18, 0x00D);
248}
249
250static int sp8870_set_frontend_parameters(struct dvb_frontend *fe)
251{
252	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
253	struct sp8870_state *state = fe->demodulator_priv;
254	int  err;
255	u16 reg0xc05;
256
257	err = configure_reg0xc05(p, &reg0xc05);
258	if (err)
259		return err;
260
261	// system controller stop
262	sp8870_microcontroller_stop(state);
263
264	// set tuner parameters
265	if (fe->ops.tuner_ops.set_params) {
266		fe->ops.tuner_ops.set_params(fe);
267		if (fe->ops.i2c_gate_ctrl)
268			fe->ops.i2c_gate_ctrl(fe, 0);
269	}
270
271	// sample rate correction bit [23..17]
272	sp8870_writereg(state, 0x0319, 0x000A);
273
274	// sample rate correction bit [16..0]
275	sp8870_writereg(state, 0x031A, 0x0AAB);
276
277	// integer carrier offset
278	sp8870_writereg(state, 0x0309, 0x0400);
279
280	// fractional carrier offset
281	sp8870_writereg(state, 0x030A, 0x0000);
282
283	// filter for 6/7/8 Mhz channel
284	if (p->bandwidth_hz == 6000000)
285		sp8870_writereg(state, 0x0311, 0x0002);
286	else if (p->bandwidth_hz == 7000000)
287		sp8870_writereg(state, 0x0311, 0x0001);
288	else
289		sp8870_writereg(state, 0x0311, 0x0000);
290
291	// scan order: 2k first = 0x0000, 8k first = 0x0001
292	if (p->transmission_mode == TRANSMISSION_MODE_2K)
293		sp8870_writereg(state, 0x0338, 0x0000);
294	else
295		sp8870_writereg(state, 0x0338, 0x0001);
296
297	sp8870_writereg(state, 0xc05, reg0xc05);
298
299	// read status reg in order to clear pending irqs
300	err = sp8870_readreg(state, 0x200);
301	if (err < 0)
302		return err;
303
304	// system controller start
305	sp8870_microcontroller_start(state);
306
307	return 0;
308}
309
310static int sp8870_init(struct dvb_frontend *fe)
311{
312	struct sp8870_state *state = fe->demodulator_priv;
313	const struct firmware *fw = NULL;
314
315	sp8870_wake_up(state);
316	if (state->initialised)
317		return 0;
318	state->initialised = 1;
319
320	dprintk("initialising frontend...\n");
321
322	/* request the firmware, this will block until someone uploads it */
323	pr_info("waiting for firmware upload (%s)...\n", SP8870_DEFAULT_FIRMWARE);
324	if (state->config->request_firmware(fe, &fw, SP8870_DEFAULT_FIRMWARE)) {
325		pr_err("no firmware upload (timeout or file not found?)\n");
326		return -EIO;
327	}
328
329	if (sp8870_firmware_upload(state, fw)) {
330		pr_err("writing firmware to device failed\n");
331		release_firmware(fw);
332		return -EIO;
333	}
334	release_firmware(fw);
335	pr_info("firmware upload complete\n");
336
337	/* enable TS output and interface pins */
338	sp8870_writereg(state, 0xc18, 0x00d);
339
340	// system controller stop
341	sp8870_microcontroller_stop(state);
342
343	// ADC mode
344	sp8870_writereg(state, 0x0301, 0x0003);
345
346	// Reed Solomon parity bytes passed to output
347	sp8870_writereg(state, 0x0C13, 0x0001);
348
349	// MPEG clock is suppressed if no valid data
350	sp8870_writereg(state, 0x0C14, 0x0001);
351
352	/* bit 0x010: enable data valid signal */
353	sp8870_writereg(state, 0x0D00, 0x010);
354	sp8870_writereg(state, 0x0D01, 0x000);
355
356	return 0;
357}
358
359static int sp8870_read_status(struct dvb_frontend *fe,
360			      enum fe_status *fe_status)
361{
362	struct sp8870_state *state = fe->demodulator_priv;
363	int status;
364	int signal;
365
366	*fe_status = 0;
367
368	status = sp8870_readreg(state, 0x0200);
369	if (status < 0)
370		return -EIO;
371
372	signal = sp8870_readreg(state, 0x0303);
373	if (signal < 0)
374		return -EIO;
375
376	if (signal > 0x0F)
377		*fe_status |= FE_HAS_SIGNAL;
378	if (status & 0x08)
379		*fe_status |= FE_HAS_SYNC;
380	if (status & 0x04)
381		*fe_status |= FE_HAS_LOCK | FE_HAS_CARRIER | FE_HAS_VITERBI;
382
383	return 0;
384}
385
386static int sp8870_read_ber(struct dvb_frontend *fe, u32 *ber)
387{
388	struct sp8870_state *state = fe->demodulator_priv;
389	int ret;
390	u32 tmp;
391
392	*ber = 0;
393
394	ret = sp8870_readreg(state, 0xC08);
395	if (ret < 0)
396		return -EIO;
397
398	tmp = ret & 0x3F;
399
400	ret = sp8870_readreg(state, 0xC07);
401	if (ret < 0)
402		return -EIO;
403
404	tmp = ret << 6;
405	if (tmp >= 0x3FFF0)
406		tmp = ~0;
407
408	*ber = tmp;
409
410	return 0;
411}
412
413static int sp8870_read_signal_strength(struct dvb_frontend *fe,  u16 *signal)
414{
415	struct sp8870_state *state = fe->demodulator_priv;
416	int ret;
417	u16 tmp;
418
419	*signal = 0;
420
421	ret = sp8870_readreg(state, 0x306);
422	if (ret < 0)
423		return -EIO;
424
425	tmp = ret << 8;
426
427	ret = sp8870_readreg(state, 0x303);
428	if (ret < 0)
429		return -EIO;
430
431	tmp |= ret;
432
433	if (tmp)
434		*signal = 0xFFFF - tmp;
435
436	return 0;
437}
438
439static int sp8870_read_uncorrected_blocks(struct dvb_frontend *fe, u32 *ublocks)
440{
441	struct sp8870_state *state = fe->demodulator_priv;
442	int ret;
443
444	*ublocks = 0;
445
446	ret = sp8870_readreg(state, 0xC0C);
447	if (ret < 0)
448		return -EIO;
449
450	if (ret == 0xFFFF)
451		ret = ~0;
452
453	*ublocks = ret;
454
455	return 0;
456}
457
458/* number of trials to recover from lockup */
459#define MAXTRIALS 5
460/* maximum checks for data valid signal */
461#define MAXCHECKS 100
462
463/* only for debugging: counter for detected lockups */
464static int lockups;
465/* only for debugging: counter for channel switches */
466static int switches;
467
468static int sp8870_set_frontend(struct dvb_frontend *fe)
469{
470	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
471	struct sp8870_state *state = fe->demodulator_priv;
472
473	/*
474	 *  The firmware of the sp8870 sometimes locks up after setting frontend parameters.
475	 *  We try to detect this by checking the data valid signal.
476	 *  If it is not set after MAXCHECKS we try to recover the lockup by setting
477	 *  the frontend parameters again.
478	 */
479
480	int err = 0;
481	int valid = 0;
482	int trials = 0;
483	int check_count = 0;
484
485	dprintk("frequency = %i\n", p->frequency);
486
487	for (trials = 1; trials <= MAXTRIALS; trials++) {
488		err = sp8870_set_frontend_parameters(fe);
489		if (err)
490			return err;
491
492		for (check_count = 0; check_count < MAXCHECKS; check_count++) {
493//			valid = ((sp8870_readreg(i2c, 0x0200) & 4) == 0);
494			valid = sp8870_read_data_valid_signal(state);
495			if (valid) {
496				dprintk("delay = %i usec\n", check_count * 10);
497				break;
498			}
499			udelay(10);
500		}
501		if (valid)
502			break;
503	}
504
505	if (!valid) {
506		pr_err("%s(): firmware crash!!!!!!\n", __func__);
507		return -EIO;
508	}
509
510	if (debug) {
511		if (valid) {
512			if (trials > 1) {
513				pr_info("%s(): firmware lockup!!!\n", __func__);
514				pr_info("%s(): recovered after %i trial(s))\n",  __func__, trials - 1);
515				lockups++;
516			}
517		}
518		switches++;
519		pr_info("%s(): switches = %i lockups = %i\n", __func__, switches, lockups);
520	}
521
522	return 0;
523}
524
525static int sp8870_sleep(struct dvb_frontend *fe)
526{
527	struct sp8870_state *state = fe->demodulator_priv;
528
529	// tristate TS output and disable interface pins
530	return sp8870_writereg(state, 0xC18, 0x000);
531}
532
533static int sp8870_get_tune_settings(struct dvb_frontend *fe, struct dvb_frontend_tune_settings *fesettings)
534{
535	fesettings->min_delay_ms = 350;
536	fesettings->step_size = 0;
537	fesettings->max_drift = 0;
538	return 0;
539}
540
541static int sp8870_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
542{
543	struct sp8870_state *state = fe->demodulator_priv;
544
545	if (enable)
546		return sp8870_writereg(state, 0x206, 0x001);
547	else
548		return sp8870_writereg(state, 0x206, 0x000);
549}
550
551static void sp8870_release(struct dvb_frontend *fe)
552{
553	struct sp8870_state *state = fe->demodulator_priv;
554
555	kfree(state);
556}
557
558static const struct dvb_frontend_ops sp8870_ops;
559
560struct dvb_frontend *sp8870_attach(const struct sp8870_config *config,
561				   struct i2c_adapter *i2c)
562{
563	struct sp8870_state *state = NULL;
564
565	/* allocate memory for the internal state */
566	state = kzalloc(sizeof(*state), GFP_KERNEL);
567	if (!state)
568		goto error;
569
570	/* setup the state */
571	state->config = config;
572	state->i2c = i2c;
573	state->initialised = 0;
574
575	/* check if the demod is there */
576	if (sp8870_readreg(state, 0x0200) < 0)
577		goto error;
578
579	/* create dvb_frontend */
580	memcpy(&state->frontend.ops, &sp8870_ops, sizeof(sp8870_ops));
581	state->frontend.demodulator_priv = state;
582	return &state->frontend;
583
584error:
585	kfree(state);
586	return NULL;
587}
588EXPORT_SYMBOL_GPL(sp8870_attach);
589
590static const struct dvb_frontend_ops sp8870_ops = {
591	.delsys = { SYS_DVBT },
592	.info = {
593		.name			= "Spase SP8870 DVB-T",
594		.frequency_min_hz	= 470 * MHz,
595		.frequency_max_hz	= 860 * MHz,
596		.frequency_stepsize_hz	= 166666,
597		.caps			= FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 |
598					  FE_CAN_FEC_3_4 | FE_CAN_FEC_5_6 |
599					  FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
600					  FE_CAN_QPSK | FE_CAN_QAM_16 |
601					  FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
602					  FE_CAN_HIERARCHY_AUTO |  FE_CAN_RECOVER
603	},
604
605	.release = sp8870_release,
606
607	.init = sp8870_init,
608	.sleep = sp8870_sleep,
609	.i2c_gate_ctrl = sp8870_i2c_gate_ctrl,
610
611	.set_frontend = sp8870_set_frontend,
612	.get_tune_settings = sp8870_get_tune_settings,
613
614	.read_status = sp8870_read_status,
615	.read_ber = sp8870_read_ber,
616	.read_signal_strength = sp8870_read_signal_strength,
617	.read_ucblocks = sp8870_read_uncorrected_blocks,
618};
619
620module_param(debug, int, 0644);
621MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
622
623MODULE_DESCRIPTION("Spase SP8870 DVB-T Demodulator driver");
624MODULE_AUTHOR("Juergen Peitz");
625MODULE_LICENSE("GPL");