summaryrefslogtreecommitdiffstats
path: root/drivers/mfd/si476x-i2c.c
blob: f5bc8e4bd4bf631b3266091a3af6212be07138cf (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
/*
 * drivers/mfd/si476x-i2c.c -- Core device driver for si476x MFD
 * device
 *
 * Copyright (C) 2012 Innovative Converged Devices(ICD)
 * Copyright (C) 2013 Andrey Smirnov
 *
 * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 */
#include <linux/module.h>

#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/regulator/consumer.h>
#include <linux/i2c.h>
#include <linux/err.h>

#include <linux/mfd/si476x-core.h>

#define SI476X_MAX_IO_ERRORS		10
#define SI476X_DRIVER_RDS_FIFO_DEPTH	128

/**
 * si476x_core_config_pinmux() - pin function configuration function
 *
 * @core: Core device structure
 *
 * Configure the functions of the pins of the radio chip.
 *
 * The function returns zero in case of succes or negative error code
 * otherwise.
 */
static int si476x_core_config_pinmux(struct si476x_core *core)
{
	int err;
	dev_dbg(&core->client->dev, "Configuring pinmux\n");
	err = si476x_core_cmd_dig_audio_pin_cfg(core,
						core->pinmux.dclk,
						core->pinmux.dfs,
						core->pinmux.dout,
						core->pinmux.xout);
	if (err < 0) {
		dev_err(&core->client->dev,
			"Failed to configure digital audio pins(err = %d)\n",
			err);
		return err;
	}

	err = si476x_core_cmd_zif_pin_cfg(core,
					  core->pinmux.iqclk,
					  core->pinmux.iqfs,
					  core->pinmux.iout,
					  core->pinmux.qout);
	if (err < 0) {
		dev_err(&core->client->dev,
			"Failed to configure ZIF pins(err = %d)\n",
			err);
		return err;
	}

	err = si476x_core_cmd_ic_link_gpo_ctl_pin_cfg(core,
						      core->pinmux.icin,
						      core->pinmux.icip,
						      core->pinmux.icon,
						      core->pinmux.icop);
	if (err < 0) {
		dev_err(&core->client->dev,
			"Failed to configure IC-Link/GPO pins(err = %d)\n",
			err);
		return err;
	}

	err = si476x_core_cmd_ana_audio_pin_cfg(core,
						core->pinmux.lrout);
	if (err < 0) {
		dev_err(&core->client->dev,
			"Failed to configure analog audio pins(err = %d)\n",
			err);
		return err;
	}

	err = si476x_core_cmd_intb_pin_cfg(core,
					   core->pinmux.intb,
					   core->pinmux.a1);
	if (err < 0) {
		dev_err(&core->client->dev,
			"Failed to configure interrupt pins(err = %d)\n",
			err);
		return err;
	}

	return 0;
}

static inline void si476x_core_schedule_polling_work(struct si476x_core *core)
{
	schedule_delayed_work(&core->status_monitor,
			      usecs_to_jiffies(SI476X_STATUS_POLL_US));
}

/**
 * si476x_core_start() - early chip startup function
 * @core: Core device structure
 * @soft: When set, this flag forces "soft" startup, where "soft"
 * power down is the one done by sending appropriate command instead
 * of using reset pin of the tuner
 *
 * Perform required startup sequence to correctly power
 * up the chip and perform initial configuration. It does the
 * following sequence of actions:
 *       1. Claims and enables the power supplies VD and VIO1 required
 *          for I2C interface of the chip operation.
 *       2. Waits for 100us, pulls the reset line up, enables irq,
 *          waits for another 100us as it is specified by the
 *          datasheet.
 *       3. Sends 'POWER_UP' command to the device with all provided
 *          information about power-up parameters.
 *       4. Configures, pin multiplexor, disables digital audio and
 *          configures interrupt sources.
 *
 * The function returns zero in case of succes or negative error code
 * otherwise.
 */
int si476x_core_start(struct si476x_core *core, bool soft)
{
	struct i2c_client *client = core->client;
	int err;

	if (!soft) {
		if (gpio_is_valid(core->gpio_reset))
			gpio_set_value_cansleep(core->gpio_reset, 1);

		if (client->irq)
			enable_irq(client->irq);

		udelay(100);

		if (!client->irq) {
			atomic_set(&core->is_alive, 1);
			si476x_core_schedule_polling_work(core);
		}
	} else {
		if (client->irq)
			enable_irq(client->irq);
		else {
			atomic_set(&core->is_alive, 1);
			si476x_core_schedule_polling_work(core);
		}
	}

	err = si476x_core_cmd_power_up(core,
				       &core->power_up_parameters);

	if (err < 0) {
		dev_err(&core->client->dev,
			"Power up failure(err = %d)\n",
			err);
		goto disable_irq;
	}

	if (client->irq)
		atomic_set(&core->is_alive, 1);

	err = si476x_core_config_pinmux(core);
	if (err < 0) {
		dev_err(&core->client->dev,
			"Failed to configure pinmux(err = %d)\n",
			err);
		goto disable_irq;
	}

	if (client->irq) {
		err = regmap_write(core->regmap,
				   SI476X_PROP_INT_CTL_ENABLE,
				   SI476X_RDSIEN |
				   SI476X_STCIEN |
				   SI476X_CTSIEN);
		if (err < 0) {
			dev_err(&core->client->dev,
				"Failed to configure interrupt sources"
				"(err = %d)\n", err);
			goto disable_irq;
		}
	}

	return 0;

disable_irq:
	if (err == -ENODEV)
		atomic_set(&core->is_alive, 0);

	if (client->irq)
		disable_irq(client->irq);
	else
		cancel_delayed_work_sync(&core->status_monitor);

	if (gpio_is_valid(core->gpio_reset))
		gpio_set_value_cansleep(core->gpio_reset, 0);

	return err;
}
EXPORT_SYMBOL_GPL(si476x_core_start);

/**
 * si476x_core_stop() - chip power-down function
 * @core: Core device structure
 * @soft: When set, function sends a POWER_DOWN command instead of
 * bringing reset line low
 *
 * Power down the chip by performing following actions:
 * 1. Disable IRQ or stop the polling worker
 * 2. Send the POWER_DOWN command if the power down is soft or bring
 *    reset line low if not.
 *
 * The function returns zero in case of succes or negative error code
 * otherwise.
 */
int si476x_core_stop(struct si476x_core *core, bool soft)
{
	int err = 0;
	atomic_set(&core->is_alive, 0);

	if (soft) {
		/* TODO: This probably shoud be a configurable option,
		 * so it is possible to have the chips keep their
		 * oscillators running
		 */
		struct si476x_power_down_args args = {
			.xosc = false,
		};
		err = si476x_core_cmd_power_down(core, &args);
	}

	/* We couldn't disable those before
	 * 'si476x_core_cmd_power_down' since we expect to get CTS
	 * interrupt */
	if (core->client->irq)
		disable_irq(core->client->irq);
	else
		cancel_delayed_work_sync(&core->status_monitor);

	if (!soft) {
		if (gpio_is_valid(core->gpio_reset))
			gpio_set_value_cansleep(core->gpio_reset, 0);
	}
	return err;
}
EXPORT_SYMBOL_GPL(si476x_core_stop);

/**
 * si476x_core_set_power_state() - set the level at which the power is
 * supplied for the chip.
 * @core: Core device structure
 * @next_state: enum si476x_power_state describing power state to
 *              switch to.
 *
 * Switch on all the required power supplies
 *
 * This function returns 0 in case of suvccess and negative error code
 * otherwise.
 */
int si476x_core_set_power_state(struct si476x_core *core,
				enum si476x_power_state next_state)
{
	/*
	   It is not clear form the datasheet if it is possible to
	   work with device if not all power domains are operational.
	   So for now the power-up policy is "power-up all the things!"
	 */
	int err = 0;

	if (core->power_state == SI476X_POWER_INCONSISTENT) {
		dev_err(&core->client->dev,
			"The device in inconsistent power state\n");
		return -EINVAL;
	}

	if (next_state != core->power_state) {
		switch (next_state) {
		case SI476X_POWER_UP_FULL:
			err = regulator_bulk_enable(ARRAY_SIZE(core->supplies),
						    core->supplies);
			if (err < 0) {
				core->power_state = SI476X_POWER_INCONSISTENT;
				break;
			}
			/*
			 * Startup timing diagram recommends to have a
			 * 100 us delay between enabling of the power
			 * supplies and turning the tuner on.
			 */
			udelay(100);

			err = si476x_core_start(core, false);
			if (err < 0)
				goto disable_regulators;

			core->power_state = next_state;
			break;

		case SI476X_POWER_DOWN:
			core->power_state = next_state;
			err = si476x_core_stop(core, false);
			if (err < 0)
				core->power_state = SI476X_POWER_INCONSISTENT;
disable_regulators:
			err = regulator_bulk_disable(ARRAY_SIZE(core->supplies),
						     core->supplies);
			if (err < 0)
				core->power_state = SI476X_POWER_INCONSISTENT;
			break;
		default:
			BUG();
		}
	}

	return err;
}
EXPORT_SYMBOL_GPL(si476x_core_set_power_state);

/**
 * si476x_core_report_drainer_stop() - mark the completion of the RDS
 * buffer drain porcess by the worker.
 *
 * @core: Core device structure
 */
static inline void si476x_core_report_drainer_stop(struct si476x_core *core)
{
	mutex_lock(&core->rds_drainer_status_lock);
	core->rds_drainer_is_working = false;
	mutex_unlock(&core->rds_drainer_status_lock);
}

/**
 * si476x_core_start_rds_drainer_once() - start RDS drainer worker if
 * ther is none working, do nothing otherwise
 *
 * @core: Datastructure corresponding to the chip.
 */
static inline void si476x_core_start_rds_drainer_once(struct si476x_core *core)
{
	mutex_lock(&core->rds_drainer_status_lock);
	if (!core->rds_drainer_is_working) {
		core->rds_drainer_is_working = true;
		schedule_work(&core->rds_fifo_drainer);
	}
	mutex_unlock(&core->rds_drainer_status_lock);
}
/**
 * si476x_drain_rds_fifo() - RDS buffer drainer.
 * @work: struct work_struct being ppassed to the function by the
 * kernel.
 *
 * Drain the contents of the RDS FIFO of
 */
static void si476x_core_drain_rds_fifo(struct work_struct *work)
{
	int err;

	struct si476x_core *core = container_of(work, struct si476x_core,
						rds_fifo_drainer);

	struct si476x_rds_status_report report;

	si476x_core_lock(core);
	err = si476x_core_cmd_fm_rds_status(core, true, false, false, &report);
	if (!err) {
		int i = report.rdsfifoused;
		dev_dbg(&core->client->dev,
			"%d elements in RDS FIFO. Draining.\n", i);
		for (; i > 0; --i) {
			err = si476x_core_cmd_fm_rds_status(core, false, false,
							    (i == 1), &report);
			if (err < 0)
				goto unlock;

			kfifo_in(&core->rds_fifo, report.rds,
				 sizeof(report.rds));
			dev_dbg(&core->client->dev, "RDS data:\n %*ph\n",
				(int)sizeof(report.rds), report.rds);
		}
		dev_dbg(&core->client->dev, "Drrrrained!\n");
		wake_up_interruptible(&core->rds_read_queue);
	}

unlock:
	si476x_core_unlock(core);
	si476x_core_report_drainer_stop(core);
}

/**
 * si476x_core_pronounce_dead()
 *
 * @core: Core device structure
 *
 * Mark the device as being dead and wake up all potentially waiting
 * threads of execution.
 *
 */
static void si476x_core_pronounce_dead(struct si476x_core *core)
{
	dev_info(&core->client->dev, "Core device is dead.\n");

	atomic_set(&core->is_alive, 0);

	/* Wake up al possible waiting processes */
	wake_up_interruptible(&core->rds_read_queue);

	atomic_set(&core->cts, 1);
	wake_up(&core->command);

	atomic_set(&core->stc, 1);
	wake_up(&core->tuning);
}

/**
 * si476x_core_i2c_xfer()
 *
 * @core: Core device structure
 * @type: Transfer type
 * @buf: Transfer buffer for/with data
 * @count: Transfer buffer size
 *
 * Perfrom and I2C transfer(either read or write) and keep a counter
 * of I/O errors. If the error counter rises above the threshold
 * pronounce device dead.
 *
 * The function returns zero on succes or negative error code on
 * failure.
 */
int si476x_core_i2c_xfer(struct si476x_core *core,
		    enum si476x_i2c_type type,
		    char *buf, int count)
{
	static int io_errors_count;
	int err;
	if (type == SI476X_I2C_SEND)
		err = i2c_master_send(core->client, buf, count);
	else
		err = i2c_master_recv(core->client, buf, count);

	if (err < 0) {
		if (io_errors_count++ > SI476X_MAX_IO_ERRORS)
			si476x_core_pronounce_dead(core);
	} else {
		io_errors_count = 0;
	}

	return err;
}
EXPORT_SYMBOL_GPL(si476x_core_i2c_xfer);

/**
 * si476x_get_status()
 * @core: Core device structure
 *
 * Get the status byte of the core device by berforming one byte I2C
 * read.
 *
 * The function returns a status value or a negative error code on
 * error.
 */
static int si476x_core_get_status(struct si476x_core *core)
{
	u8 response;
	int err = si476x_core_i2c_xfer(core, SI476X_I2C_RECV,
				  &response, sizeof(response));

	return (err < 0) ? err : response;
}

/**
 * si476x_get_and_signal_status() - IRQ dispatcher
 * @core: Core device structure
 *
 * Dispatch the arrived interrupt request based on the value of the
 * status byte reported by the tuner.
 *
 */
static void si476x_core_get_and_signal_status(struct si476x_core *core)
{
	int status = si476x_core_get_status(core);
	if (status < 0) {
		dev_err(&core->client->dev, "Failed to get status\n");
		return;
	}

	if (status & SI476X_CTS) {
		/* Unfortunately completions could not be used for
		 * signalling CTS since this flag cannot be cleared
		 * in status byte, and therefore once it becomes true
		 * multiple calls to 'complete' would cause the
		 * commands following the current one to be completed
		 * before they actually are */
		dev_dbg(&core->client->dev, "[interrupt] CTSINT\n");
		atomic_set(&core->cts, 1);
		wake_up(&core->command);
	}

	if (status & SI476X_FM_RDS_INT) {
		dev_dbg(&core->client->dev, "[interrupt] RDSINT\n");
		si476x_core_start_rds_drainer_once(core);
	}

	if (status & SI476X_STC_INT) {
		dev_dbg(&core->client->dev, "[interrupt] STCINT\n");
		atomic_set(&core->stc, 1);
		wake_up(&core->tuning);
	}
}

static void si476x_core_poll_loop(struct work_struct *work)
{
	struct si476x_core *core = SI476X_WORK_TO_CORE(work);

	si476x_core_get_and_signal_status(core);

	if (atomic_read(&core->is_alive))
		si476x_core_schedule_polling_work(core);
}

static irqreturn_t si476x_core_interrupt(int irq, void *dev)
{
	struct si476x_core *core = dev;

	si476x_core_get_and_signal_status(core);

	return IRQ_HANDLED;
}

/**
 * si476x_firmware_version_to_revision()
 * @core: Core device structure
 * @major:  Firmware major number
 * @minor1: Firmware first minor number
 * @minor2: Firmware second minor number
 *
 * Convert a chip's firmware version number into an offset that later
 * will be used to as offset in "vtable" of tuner functions
 *
 * This function returns a positive offset in case of success and a -1
 * in case of failure.
 */
static int si476x_core_fwver_to_revision(struct si476x_core *core,
					 int func, int major,
					 int minor1, int minor2)
{
	switch (func) {
	case SI476X_FUNC_FM_RECEIVER:
		switch (major) {
		case 5:
			return SI476X_REVISION_A10;
		case 8:
			return SI476X_REVISION_A20;
		case 10:
			return SI476X_REVISION_A30;
		default:
			goto unknown_revision;
		}
	case SI476X_FUNC_AM_RECEIVER:
		switch (major) {
		case 5:
			return SI476X_REVISION_A10;
		case 7:
			return SI476X_REVISION_A20;
		case 9:
			return SI476X_REVISION_A30;
		default:
			goto unknown_revision;
		}
	case SI476X_FUNC_WB_RECEIVER:
		switch (major) {
		case 3:
			return SI476X_REVISION_A10;
		case 5:
			return SI476X_REVISION_A20;
		case 7:
			return SI476X_REVISION_A30;
		default:
			goto unknown_revision;
		}
	case SI476X_FUNC_BOOTLOADER:
	default:		/* FALLTHROUG */
		BUG();
		return -1;
	}

unknown_revision:
	dev_err(&core->client->dev,
		"Unsupported version of the firmware: %d.%d.%d, "
		"reverting to A10 comptible functions\n",
		major, minor1, minor2);

	return SI476X_REVISION_A10;
}

/**
 * si476x_get_revision_info()
 * @core: Core device structure
 *
 * Get the firmware version number of the device. It is done in
 * following three steps:
 *    1. Power-up the device
 *    2. Send the 'FUNC_INFO' command
 *    3. Powering the device down.
 *
 * The function return zero on success and a negative error code on
 * failure.
 */
static int si476x_core_get_revision_info(struct si476x_core *core)
{
	int rval;
	struct si476x_func_info info;

	si476x_core_lock(core);
	rval = si476x_core_set_power_state(core, SI476X_POWER_UP_FULL);
	if (rval < 0)
		goto exit;

	rval = si476x_core_cmd_func_info(core, &info);
	if (rval < 0)
		goto power_down;

	core->revision = si476x_core_fwver_to_revision(core, info.func,
						       info.firmware.major,
						       info.firmware.minor[0],
						       info.firmware.minor[1]);
power_down:
	si476x_core_set_power_state(core, SI476X_POWER_DOWN);
exit:
	si476x_core_unlock(core);

	return rval;
}

bool si476x_core_has_am(struct si476x_core *core)
{
	return core->chip_id == SI476X_CHIP_SI4761 ||
		core->chip_id == SI476X_CHIP_SI4764;
}
EXPORT_SYMBOL_GPL(si476x_core_has_am);

bool si476x_core_has_diversity(struct si476x_core *core)
{
	return core->chip_id == SI476X_CHIP_SI4764;
}
EXPORT_SYMBOL_GPL(si476x_core_has_diversity);

bool si476x_core_is_a_secondary_tuner(struct si476x_core *core)
{
	return si476x_core_has_diversity(core) &&
		(core->diversity_mode == SI476X_PHDIV_SECONDARY_ANTENNA ||
		 core->diversity_mode == SI476X_PHDIV_SECONDARY_COMBINING);
}
EXPORT_SYMBOL_GPL(si476x_core_is_a_secondary_tuner);

bool si476x_core_is_a_primary_tuner(struct si476x_core *core)
{
	return si476x_core_has_diversity(core) &&
		(core->diversity_mode == SI476X_PHDIV_PRIMARY_ANTENNA ||
		 core->diversity_mode == SI476X_PHDIV_PRIMARY_COMBINING);
}
EXPORT_SYMBOL_GPL(si476x_core_is_a_primary_tuner);

bool si476x_core_is_in_am_receiver_mode(struct si476x_core *core)
{
	return si476x_core_has_am(core) &&
		(core->power_up_parameters.func == SI476X_FUNC_AM_RECEIVER);
}
EXPORT_SYMBOL_GPL(si476x_core_is_in_am_receiver_mode);

bool si476x_core_is_powered_up(struct si476x_core *core)
{
	return core->power_state == SI476X_POWER_UP_FULL;
}
EXPORT_SYMBOL_GPL(si476x_core_is_powered_up);

static int si476x_core_probe(struct i2c_client *client,
			     const struct i2c_device_id *id)
{
	int rval;
	struct si476x_core          *core;
	struct si476x_platform_data *pdata;
	struct mfd_cell *cell;
	int              cell_num;

	core = devm_kzalloc(&client->dev, sizeof(*core), GFP_KERNEL);
	if (!core) {
		dev_err(&client->dev,
			"failed to allocate 'struct si476x_core'\n");
		return -ENOMEM;
	}
	core->client = client;

	core->regmap = devm_regmap_init_si476x(core);
	if (IS_ERR(core->regmap)) {
		rval = PTR_ERR(core->regmap);
		dev_err(&client->dev,
			"Failed to allocate register map: %d\n",
			rval);
		return rval;
	}

	i2c_set_clientdata(client, core);

	atomic_set(&core->is_alive, 0);
	core->power_state = SI476X_POWER_DOWN;

	pdata = client->dev.platform_data;
	if (pdata) {
		memcpy(&core->power_up_parameters,
		       &pdata->power_up_parameters,
		       sizeof(core->power_up_parameters));

		core->gpio_reset = -1;
		if (gpio_is_valid(pdata->gpio_reset)) {
			rval = gpio_request(pdata->gpio_reset, "si476x reset");
			if (rval) {
				dev_err(&client->dev,
					"Failed to request gpio: %d\n", rval);
				return rval;
			}
			core->gpio_reset = pdata->gpio_reset;
			gpio_direction_output(core->gpio_reset, 0);
		}

		core->diversity_mode = pdata->diversity_mode;
		memcpy(&core->pinmux, &pdata->pinmux,
		       sizeof(struct si476x_pinmux));
	} else {
		dev_err(&client->dev, "No platform data provided\n");
		return -EINVAL;
	}

	core->supplies[0].supply = "vd";
	core->supplies[1].supply = "va";
	core->supplies[2].supply = "vio1";
	core->supplies[3].supply = "vio2";

	rval = devm_regulator_bulk_get(&client->dev,
				       ARRAY_SIZE(core->supplies),
				       core->supplies);
	if (rval) {
		dev_err(&client->dev, "Failet to gett all of the regulators\n");
		goto free_gpio;
	}

	mutex_init(&core->cmd_lock);
	init_waitqueue_head(&core->command);
	init_waitqueue_head(&core->tuning);

	rval = kfifo_alloc(&core->rds_fifo,
			   SI476X_DRIVER_RDS_FIFO_DEPTH *
			   sizeof(struct v4l2_rds_data),
			   GFP_KERNEL);
	if (rval) {
		dev_err(&client->dev, "Could not alloate the FIFO\n");
		goto free_gpio;
	}
	mutex_init(&core->rds_drainer_status_lock);
	init_waitqueue_head(&core->rds_read_queue);
	INIT_WORK(&core->rds_fifo_drainer, si476x_core_drain_rds_fifo);

	if (client->irq) {
		rval = devm_request_threaded_irq(&client->dev,
						 client->irq, NULL,
						 si476x_core_interrupt,
						 IRQF_TRIGGER_FALLING,
						 client->name, core);
		if (rval < 0) {
			dev_err(&client->dev, "Could not request IRQ %d\n",
				client->irq);
			goto free_kfifo;
		}
		disable_irq(client->irq);
		dev_dbg(&client->dev, "IRQ requested.\n");

		core->rds_fifo_depth = 20;
	} else {
		INIT_DELAYED_WORK(&core->status_monitor,
				  si476x_core_poll_loop);
		dev_info(&client->dev,
			 "No IRQ number specified, will use polling\n");

		core->rds_fifo_depth = 5;
	}

	core->chip_id = id->driver_data;

	rval = si476x_core_get_revision_info(core);
	if (rval < 0) {
		rval = -ENODEV;
		goto free_kfifo;
	}

	cell_num = 0;

	cell = &core->cells[SI476X_RADIO_CELL];
	cell->name = "si476x-radio";
	cell_num++;

#ifdef CONFIG_SND_SOC_SI476X
	if ((core->chip_id == SI476X_CHIP_SI4761 ||
	     core->chip_id == SI476X_CHIP_SI4764)	&&
	    core->pinmux.dclk == SI476X_DCLK_DAUDIO     &&
	    core->pinmux.dfs  == SI476X_DFS_DAUDIO      &&
	    core->pinmux.dout == SI476X_DOUT_I2S_OUTPUT &&
	    core->pinmux.xout == SI476X_XOUT_TRISTATE) {
		cell = &core->cells[SI476X_CODEC_CELL];
		cell->name          = "si476x-codec";
		cell_num++;
	}
#endif
	rval = mfd_add_devices(&client->dev,
			       (client->adapter->nr << 8) + client->addr,
			       core->cells, cell_num,
			       NULL, 0, NULL);
	if (!rval)
		return 0;

free_kfifo:
	kfifo_free(&core->rds_fifo);

free_gpio:
	if (gpio_is_valid(core->gpio_reset))
		gpio_free(core->gpio_reset);

	return rval;
}

static int si476x_core_remove(struct i2c_client *client)
{
	struct si476x_core *core = i2c_get_clientdata(client);

	si476x_core_pronounce_dead(core);
	mfd_remove_devices(&client->dev);

	if (client->irq)
		disable_irq(client->irq);
	else
		cancel_delayed_work_sync(&core->status_monitor);

	kfifo_free(&core->rds_fifo);

	if (gpio_is_valid(core->gpio_reset))
		gpio_free(core->gpio_reset);

	return 0;
}


static const struct i2c_device_id si476x_id[] = {
	{ "si4761", SI476X_CHIP_SI4761 },
	{ "si4764", SI476X_CHIP_SI4764 },
	{ "si4768", SI476X_CHIP_SI4768 },
	{ },
};
MODULE_DEVICE_TABLE(i2c, si476x_id);

static struct i2c_driver si476x_core_driver = {
	.driver		= {
		.name	= "si476x-core",
		.owner  = THIS_MODULE,
	},
	.probe		= si476x_core_probe,
	.remove         = si476x_core_remove,
	.id_table       = si476x_id,
};
module_i2c_driver(si476x_core_driver);


MODULE_AUTHOR("Andrey Smirnov <andrew.smirnov@gmail.com>");
MODULE_DESCRIPTION("Si4761/64/68 AM/FM MFD core device driver");
MODULE_LICENSE("GPL");