Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
  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
// SPDX-License-Identifier: (GPL-2.0 OR MIT)
//
// Copyright (c) 2018 BayLibre, SAS.
// Author: Jerome Brunet <jbrunet@baylibre.com>

#include <linux/clk.h>
#include <linux/module.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/regmap.h>
#include <sound/soc.h>
#include <sound/soc-dai.h>
#include <sound/pcm_params.h>

#define PDM_CTRL			0x00
#define  PDM_CTRL_EN			BIT(31)
#define  PDM_CTRL_OUT_MODE		BIT(29)
#define  PDM_CTRL_BYPASS_MODE		BIT(28)
#define  PDM_CTRL_RST_FIFO		BIT(16)
#define  PDM_CTRL_CHAN_RSTN_MASK	GENMASK(15, 8)
#define  PDM_CTRL_CHAN_RSTN(x)		((x) << 8)
#define  PDM_CTRL_CHAN_EN_MASK		GENMASK(7, 0)
#define  PDM_CTRL_CHAN_EN(x)		((x) << 0)
#define PDM_HCIC_CTRL1			0x04
#define  PDM_FILTER_EN			BIT(31)
#define  PDM_HCIC_CTRL1_GAIN_SFT_MASK	GENMASK(29, 24)
#define  PDM_HCIC_CTRL1_GAIN_SFT(x)	((x) << 24)
#define  PDM_HCIC_CTRL1_GAIN_MULT_MASK	GENMASK(23, 16)
#define  PDM_HCIC_CTRL1_GAIN_MULT(x)	((x) << 16)
#define  PDM_HCIC_CTRL1_DSR_MASK	GENMASK(8, 4)
#define  PDM_HCIC_CTRL1_DSR(x)		((x) << 4)
#define  PDM_HCIC_CTRL1_STAGE_NUM_MASK	GENMASK(3, 0)
#define  PDM_HCIC_CTRL1_STAGE_NUM(x)	((x) << 0)
#define PDM_HCIC_CTRL2			0x08
#define PDM_F1_CTRL			0x0c
#define  PDM_LPF_ROUND_MODE_MASK	GENMASK(17, 16)
#define  PDM_LPF_ROUND_MODE(x)		((x) << 16)
#define  PDM_LPF_DSR_MASK		GENMASK(15, 12)
#define  PDM_LPF_DSR(x)			((x) << 12)
#define  PDM_LPF_STAGE_NUM_MASK		GENMASK(8, 0)
#define  PDM_LPF_STAGE_NUM(x)		((x) << 0)
#define  PDM_LPF_MAX_STAGE		336
#define  PDM_LPF_NUM			3
#define PDM_F2_CTRL			0x10
#define PDM_F3_CTRL			0x14
#define PDM_HPF_CTRL			0x18
#define  PDM_HPF_SFT_STEPS_MASK		GENMASK(20, 16)
#define  PDM_HPF_SFT_STEPS(x)		((x) << 16)
#define  PDM_HPF_OUT_FACTOR_MASK	GENMASK(15, 0)
#define  PDM_HPF_OUT_FACTOR(x)		((x) << 0)
#define PDM_CHAN_CTRL			0x1c
#define  PDM_CHAN_CTRL_POINTER_WIDTH	8
#define  PDM_CHAN_CTRL_POINTER_MAX	((1 << PDM_CHAN_CTRL_POINTER_WIDTH) - 1)
#define  PDM_CHAN_CTRL_NUM		4
#define PDM_CHAN_CTRL1			0x20
#define PDM_COEFF_ADDR			0x24
#define PDM_COEFF_DATA			0x28
#define PDM_CLKG_CTRL			0x2c
#define PDM_STS				0x30

struct axg_pdm_lpf {
	unsigned int ds;
	unsigned int round_mode;
	const unsigned int *tap;
	unsigned int tap_num;
};

struct axg_pdm_hcic {
	unsigned int shift;
	unsigned int mult;
	unsigned int steps;
	unsigned int ds;
};

struct axg_pdm_hpf {
	unsigned int out_factor;
	unsigned int steps;
};

struct axg_pdm_filters {
	struct axg_pdm_hcic hcic;
	struct axg_pdm_hpf hpf;
	struct axg_pdm_lpf lpf[PDM_LPF_NUM];
};

struct axg_pdm_cfg {
	const struct axg_pdm_filters *filters;
	unsigned int sys_rate;
};

struct axg_pdm {
	const struct axg_pdm_cfg *cfg;
	struct regmap *map;
	struct clk *dclk;
	struct clk *sysclk;
	struct clk *pclk;
};

static void axg_pdm_enable(struct regmap *map)
{
	/* Reset AFIFO */
	regmap_update_bits(map, PDM_CTRL, PDM_CTRL_RST_FIFO, PDM_CTRL_RST_FIFO);
	regmap_update_bits(map, PDM_CTRL, PDM_CTRL_RST_FIFO, 0);

	/* Enable PDM */
	regmap_update_bits(map, PDM_CTRL, PDM_CTRL_EN, PDM_CTRL_EN);
}

static void axg_pdm_disable(struct regmap *map)
{
	regmap_update_bits(map, PDM_CTRL, PDM_CTRL_EN, 0);
}

static void axg_pdm_filters_enable(struct regmap *map, bool enable)
{
	unsigned int val = enable ? PDM_FILTER_EN : 0;

	regmap_update_bits(map, PDM_HCIC_CTRL1, PDM_FILTER_EN, val);
	regmap_update_bits(map, PDM_F1_CTRL, PDM_FILTER_EN, val);
	regmap_update_bits(map, PDM_F2_CTRL, PDM_FILTER_EN, val);
	regmap_update_bits(map, PDM_F3_CTRL, PDM_FILTER_EN, val);
	regmap_update_bits(map, PDM_HPF_CTRL, PDM_FILTER_EN, val);
}

static int axg_pdm_trigger(struct snd_pcm_substream *substream, int cmd,
			   struct snd_soc_dai *dai)
{
	struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		axg_pdm_enable(priv->map);
		return 0;

	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		axg_pdm_disable(priv->map);
		return 0;

	default:
		return -EINVAL;
	}
}

static unsigned int axg_pdm_get_os(struct axg_pdm *priv)
{
	const struct axg_pdm_filters *filters = priv->cfg->filters;
	unsigned int os = filters->hcic.ds;
	int i;

	/*
	 * The global oversampling factor is defined by the down sampling
	 * factor applied by each filter (HCIC and LPFs)
	 */

	for (i = 0; i < PDM_LPF_NUM; i++)
		os *= filters->lpf[i].ds;

	return os;
}

static int axg_pdm_set_sysclk(struct axg_pdm *priv, unsigned int os,
			      unsigned int rate)
{
	unsigned int sys_rate = os * 2 * rate * PDM_CHAN_CTRL_POINTER_MAX;

	/*
	 * Set the default system clock rate unless it is too fast for
	 * for the requested sample rate. In this case, the sample pointer
	 * counter could overflow so set a lower system clock rate
	 */
	if (sys_rate < priv->cfg->sys_rate)
		return clk_set_rate(priv->sysclk, sys_rate);

	return clk_set_rate(priv->sysclk, priv->cfg->sys_rate);
}

static int axg_pdm_set_sample_pointer(struct axg_pdm *priv)
{
	unsigned int spmax, sp, val;
	int i;

	/* Max sample counter value per half period of dclk */
	spmax = DIV_ROUND_UP_ULL((u64)clk_get_rate(priv->sysclk),
				 clk_get_rate(priv->dclk) * 2);

	/* Check if sysclk is not too fast - should not happen */
	if (WARN_ON(spmax > PDM_CHAN_CTRL_POINTER_MAX))
		return -EINVAL;

	/* Capture the data when we are at 75% of the half period */
	sp = spmax * 3 / 4;

	for (i = 0, val = 0; i < PDM_CHAN_CTRL_NUM; i++)
		val |= sp << (PDM_CHAN_CTRL_POINTER_WIDTH * i);

	regmap_write(priv->map, PDM_CHAN_CTRL, val);
	regmap_write(priv->map, PDM_CHAN_CTRL1, val);

	return 0;
}

static void axg_pdm_set_channel_mask(struct axg_pdm *priv,
				     unsigned int channels)
{
	unsigned int mask = GENMASK(channels - 1, 0);

	/* Put all channel in reset */
	regmap_update_bits(priv->map, PDM_CTRL,
			   PDM_CTRL_CHAN_RSTN_MASK, 0);

	/* Take the necessary channels out of reset and enable them */
	regmap_update_bits(priv->map, PDM_CTRL,
			   PDM_CTRL_CHAN_RSTN_MASK |
			   PDM_CTRL_CHAN_EN_MASK,
			   PDM_CTRL_CHAN_RSTN(mask) |
			   PDM_CTRL_CHAN_EN(mask));
}

static int axg_pdm_hw_params(struct snd_pcm_substream *substream,
			     struct snd_pcm_hw_params *params,
			     struct snd_soc_dai *dai)
{
	struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
	unsigned int os = axg_pdm_get_os(priv);
	unsigned int rate = params_rate(params);
	unsigned int val;
	int ret;

	switch (params_width(params)) {
	case 24:
		val = PDM_CTRL_OUT_MODE;
		break;
	case 32:
		val = 0;
		break;
	default:
		dev_err(dai->dev, "unsupported sample width\n");
		return -EINVAL;
	}

	regmap_update_bits(priv->map, PDM_CTRL, PDM_CTRL_OUT_MODE, val);

	ret = axg_pdm_set_sysclk(priv, os, rate);
	if (ret) {
		dev_err(dai->dev, "failed to set system clock\n");
		return ret;
	}

	ret = clk_set_rate(priv->dclk, rate * os);
	if (ret) {
		dev_err(dai->dev, "failed to set dclk\n");
		return ret;
	}

	ret = axg_pdm_set_sample_pointer(priv);
	if (ret) {
		dev_err(dai->dev, "invalid clock setting\n");
		return ret;
	}

	axg_pdm_set_channel_mask(priv, params_channels(params));

	return 0;
}

static int axg_pdm_startup(struct snd_pcm_substream *substream,
			   struct snd_soc_dai *dai)
{
	struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
	int ret;

	ret = clk_prepare_enable(priv->dclk);
	if (ret) {
		dev_err(dai->dev, "enabling dclk failed\n");
		return ret;
	}

	/* Enable the filters */
	axg_pdm_filters_enable(priv->map, true);

	return ret;
}

static void axg_pdm_shutdown(struct snd_pcm_substream *substream,
			     struct snd_soc_dai *dai)
{
	struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);

	axg_pdm_filters_enable(priv->map, false);
	clk_disable_unprepare(priv->dclk);
}

static const struct snd_soc_dai_ops axg_pdm_dai_ops = {
	.trigger	= axg_pdm_trigger,
	.hw_params	= axg_pdm_hw_params,
	.startup	= axg_pdm_startup,
	.shutdown	= axg_pdm_shutdown,
};

static void axg_pdm_set_hcic_ctrl(struct axg_pdm *priv)
{
	const struct axg_pdm_hcic *hcic = &priv->cfg->filters->hcic;
	unsigned int val;

	val = PDM_HCIC_CTRL1_STAGE_NUM(hcic->steps);
	val |= PDM_HCIC_CTRL1_DSR(hcic->ds);
	val |= PDM_HCIC_CTRL1_GAIN_MULT(hcic->mult);
	val |= PDM_HCIC_CTRL1_GAIN_SFT(hcic->shift);

	regmap_update_bits(priv->map, PDM_HCIC_CTRL1,
			   PDM_HCIC_CTRL1_STAGE_NUM_MASK |
			   PDM_HCIC_CTRL1_DSR_MASK |
			   PDM_HCIC_CTRL1_GAIN_MULT_MASK |
			   PDM_HCIC_CTRL1_GAIN_SFT_MASK,
			   val);
}

static void axg_pdm_set_lpf_ctrl(struct axg_pdm *priv, unsigned int index)
{
	const struct axg_pdm_lpf *lpf = &priv->cfg->filters->lpf[index];
	unsigned int offset = index * regmap_get_reg_stride(priv->map)
		+ PDM_F1_CTRL;
	unsigned int val;

	val = PDM_LPF_STAGE_NUM(lpf->tap_num);
	val |= PDM_LPF_DSR(lpf->ds);
	val |= PDM_LPF_ROUND_MODE(lpf->round_mode);

	regmap_update_bits(priv->map, offset,
			   PDM_LPF_STAGE_NUM_MASK |
			   PDM_LPF_DSR_MASK |
			   PDM_LPF_ROUND_MODE_MASK,
			   val);
}

static void axg_pdm_set_hpf_ctrl(struct axg_pdm *priv)
{
	const struct axg_pdm_hpf *hpf = &priv->cfg->filters->hpf;
	unsigned int val;

	val = PDM_HPF_OUT_FACTOR(hpf->out_factor);
	val |= PDM_HPF_SFT_STEPS(hpf->steps);

	regmap_update_bits(priv->map, PDM_HPF_CTRL,
			   PDM_HPF_OUT_FACTOR_MASK |
			   PDM_HPF_SFT_STEPS_MASK,
			   val);
}

static int axg_pdm_set_lpf_filters(struct axg_pdm *priv)
{
	const struct axg_pdm_lpf *lpf = priv->cfg->filters->lpf;
	unsigned int count = 0;
	int i, j;

	for (i = 0; i < PDM_LPF_NUM; i++)
		count += lpf[i].tap_num;

	/* Make sure the coeffs fit in the memory */
	if (count >= PDM_LPF_MAX_STAGE)
		return -EINVAL;

	/* Set the initial APB bus register address */
	regmap_write(priv->map, PDM_COEFF_ADDR, 0);

	/* Set the tap filter values of all 3 filters */
	for (i = 0; i < PDM_LPF_NUM; i++) {
		axg_pdm_set_lpf_ctrl(priv, i);

		for (j = 0; j < lpf[i].tap_num; j++)
			regmap_write(priv->map, PDM_COEFF_DATA, lpf[i].tap[j]);
	}

	return 0;
}

static int axg_pdm_dai_probe(struct snd_soc_dai *dai)
{
	struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);
	int ret;

	ret = clk_prepare_enable(priv->pclk);
	if (ret) {
		dev_err(dai->dev, "enabling pclk failed\n");
		return ret;
	}

	/*
	 * sysclk must be set and enabled as well to access the pdm registers
	 * Accessing the register w/o it will give a bus error.
	 */
	ret = clk_set_rate(priv->sysclk, priv->cfg->sys_rate);
	if (ret) {
		dev_err(dai->dev, "setting sysclk failed\n");
		goto err_pclk;
	}

	ret = clk_prepare_enable(priv->sysclk);
	if (ret) {
		dev_err(dai->dev, "enabling sysclk failed\n");
		goto err_pclk;
	}

	/* Make sure the device is initially disabled */
	axg_pdm_disable(priv->map);

	/* Make sure filter bypass is disabled */
	regmap_update_bits(priv->map, PDM_CTRL, PDM_CTRL_BYPASS_MODE, 0);

	/* Load filter settings */
	axg_pdm_set_hcic_ctrl(priv);
	axg_pdm_set_hpf_ctrl(priv);

	ret = axg_pdm_set_lpf_filters(priv);
	if (ret) {
		dev_err(dai->dev, "invalid filter configuration\n");
		goto err_sysclk;
	}

	return 0;

err_sysclk:
	clk_disable_unprepare(priv->sysclk);
err_pclk:
	clk_disable_unprepare(priv->pclk);
	return ret;
}

static int axg_pdm_dai_remove(struct snd_soc_dai *dai)
{
	struct axg_pdm *priv = snd_soc_dai_get_drvdata(dai);

	clk_disable_unprepare(priv->sysclk);
	clk_disable_unprepare(priv->pclk);

	return 0;
}

static struct snd_soc_dai_driver axg_pdm_dai_drv = {
	.name = "PDM",
	.capture = {
		.stream_name	= "Capture",
		.channels_min	= 1,
		.channels_max	= 8,
		.rates		= SNDRV_PCM_RATE_CONTINUOUS,
		.rate_min	= 5512,
		.rate_max	= 48000,
		.formats	= (SNDRV_PCM_FMTBIT_S24_LE |
				   SNDRV_PCM_FMTBIT_S32_LE),
	},
	.ops		= &axg_pdm_dai_ops,
	.probe		= axg_pdm_dai_probe,
	.remove		= axg_pdm_dai_remove,
};

static const struct snd_soc_component_driver axg_pdm_component_drv = {};

static const struct regmap_config axg_pdm_regmap_cfg = {
	.reg_bits	= 32,
	.val_bits	= 32,
	.reg_stride	= 4,
	.max_register	= PDM_STS,
};

static const unsigned int lpf1_default_tap[] = {
	0x000014, 0xffffb2, 0xfffed9, 0xfffdce, 0xfffd45,
	0xfffe32, 0x000147, 0x000645, 0x000b86, 0x000e21,
	0x000ae3, 0x000000, 0xffeece, 0xffdca8, 0xffd212,
	0xffd7d1, 0xfff2a7, 0x001f4c, 0x0050c2, 0x0072aa,
	0x006ff1, 0x003c32, 0xffdc4e, 0xff6a18, 0xff0fef,
	0xfefbaf, 0xff4c40, 0x000000, 0x00ebc8, 0x01c077,
	0x02209e, 0x01c1a4, 0x008e60, 0xfebe52, 0xfcd690,
	0xfb8fa5, 0xfba498, 0xfd9812, 0x0181ce, 0x06f5f3,
	0x0d112f, 0x12a958, 0x169686, 0x18000e, 0x169686,
	0x12a958, 0x0d112f, 0x06f5f3, 0x0181ce, 0xfd9812,
	0xfba498, 0xfb8fa5, 0xfcd690, 0xfebe52, 0x008e60,
	0x01c1a4, 0x02209e, 0x01c077, 0x00ebc8, 0x000000,
	0xff4c40, 0xfefbaf, 0xff0fef, 0xff6a18, 0xffdc4e,
	0x003c32, 0x006ff1, 0x0072aa, 0x0050c2, 0x001f4c,
	0xfff2a7, 0xffd7d1, 0xffd212, 0xffdca8, 0xffeece,
	0x000000, 0x000ae3, 0x000e21, 0x000b86, 0x000645,
	0x000147, 0xfffe32, 0xfffd45, 0xfffdce, 0xfffed9,
	0xffffb2, 0x000014,
};

static const unsigned int lpf2_default_tap[] = {
	0x00050a, 0xfff004, 0x0002c1, 0x003c12, 0xffa818,
	0xffc87d, 0x010aef, 0xff5223, 0xfebd93, 0x028f41,
	0xff5c0e, 0xfc63f8, 0x055f81, 0x000000, 0xf478a0,
	0x11c5e3, 0x2ea74d, 0x11c5e3, 0xf478a0, 0x000000,
	0x055f81, 0xfc63f8, 0xff5c0e, 0x028f41, 0xfebd93,
	0xff5223, 0x010aef, 0xffc87d, 0xffa818, 0x003c12,
	0x0002c1, 0xfff004, 0x00050a,
};

static const unsigned int lpf3_default_tap[] = {
	0x000000, 0x000081, 0x000000, 0xfffedb, 0x000000,
	0x00022d, 0x000000, 0xfffc46, 0x000000, 0x0005f7,
	0x000000, 0xfff6eb, 0x000000, 0x000d4e, 0x000000,
	0xffed1e, 0x000000, 0x001a1c, 0x000000, 0xffdcb0,
	0x000000, 0x002ede, 0x000000, 0xffc2d1, 0x000000,
	0x004ebe, 0x000000, 0xff9beb, 0x000000, 0x007dd7,
	0x000000, 0xff633a, 0x000000, 0x00c1d2, 0x000000,
	0xff11d5, 0x000000, 0x012368, 0x000000, 0xfe9c45,
	0x000000, 0x01b252, 0x000000, 0xfdebf6, 0x000000,
	0x0290b8, 0x000000, 0xfcca0d, 0x000000, 0x041d7c,
	0x000000, 0xfa8152, 0x000000, 0x07e9c6, 0x000000,
	0xf28fb5, 0x000000, 0x28b216, 0x3fffde, 0x28b216,
	0x000000, 0xf28fb5, 0x000000, 0x07e9c6, 0x000000,
	0xfa8152, 0x000000, 0x041d7c, 0x000000, 0xfcca0d,
	0x000000, 0x0290b8, 0x000000, 0xfdebf6, 0x000000,
	0x01b252, 0x000000, 0xfe9c45, 0x000000, 0x012368,
	0x000000, 0xff11d5, 0x000000, 0x00c1d2, 0x000000,
	0xff633a, 0x000000, 0x007dd7, 0x000000, 0xff9beb,
	0x000000, 0x004ebe, 0x000000, 0xffc2d1, 0x000000,
	0x002ede, 0x000000, 0xffdcb0, 0x000000, 0x001a1c,
	0x000000, 0xffed1e, 0x000000, 0x000d4e, 0x000000,
	0xfff6eb, 0x000000, 0x0005f7, 0x000000, 0xfffc46,
	0x000000, 0x00022d, 0x000000, 0xfffedb, 0x000000,
	0x000081, 0x000000,
};

/*
 * These values are sane defaults for the axg platform:
 * - OS = 64
 * - Latency = 38700 (?)
 *
 * TODO: There is a lot of different HCIC, LPFs and HPF configurations possible.
 *       the configuration may depend on the dmic used by the platform, the
 *       expected tradeoff between latency and quality, etc ... If/When other
 *       settings are required, we should add a fw interface to this driver to
 *       load new filter settings.
 */
static const struct axg_pdm_filters axg_default_filters = {
	.hcic = {
		.shift = 0x15,
		.mult = 0x80,
		.steps = 7,
		.ds = 8,
	},
	.hpf = {
		.out_factor = 0x8000,
		.steps = 13,
	},
	.lpf = {
		[0] = {
			.ds = 2,
			.round_mode = 1,
			.tap = lpf1_default_tap,
			.tap_num = ARRAY_SIZE(lpf1_default_tap),
		},
		[1] = {
			.ds = 2,
			.round_mode = 0,
			.tap = lpf2_default_tap,
			.tap_num = ARRAY_SIZE(lpf2_default_tap),
		},
		[2] = {
			.ds = 2,
			.round_mode = 1,
			.tap = lpf3_default_tap,
			.tap_num = ARRAY_SIZE(lpf3_default_tap)
		},
	},
};

static const struct axg_pdm_cfg axg_pdm_config = {
	.filters = &axg_default_filters,
	.sys_rate = 250000000,
};

static const struct of_device_id axg_pdm_of_match[] = {
	{
		.compatible = "amlogic,axg-pdm",
		.data = &axg_pdm_config,
	}, {}
};
MODULE_DEVICE_TABLE(of, axg_pdm_of_match);

static int axg_pdm_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct axg_pdm *priv;
	void __iomem *regs;
	int ret;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;
	platform_set_drvdata(pdev, priv);

	priv->cfg = of_device_get_match_data(dev);
	if (!priv->cfg) {
		dev_err(dev, "failed to match device\n");
		return -ENODEV;
	}

	regs = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(regs))
		return PTR_ERR(regs);

	priv->map = devm_regmap_init_mmio(dev, regs, &axg_pdm_regmap_cfg);
	if (IS_ERR(priv->map)) {
		dev_err(dev, "failed to init regmap: %ld\n",
			PTR_ERR(priv->map));
		return PTR_ERR(priv->map);
	}

	priv->pclk = devm_clk_get(dev, "pclk");
	if (IS_ERR(priv->pclk)) {
		ret = PTR_ERR(priv->pclk);
		if (ret != -EPROBE_DEFER)
			dev_err(dev, "failed to get pclk: %d\n", ret);
		return ret;
	}

	priv->dclk = devm_clk_get(dev, "dclk");
	if (IS_ERR(priv->dclk)) {
		ret = PTR_ERR(priv->dclk);
		if (ret != -EPROBE_DEFER)
			dev_err(dev, "failed to get dclk: %d\n", ret);
		return ret;
	}

	priv->sysclk = devm_clk_get(dev, "sysclk");
	if (IS_ERR(priv->sysclk)) {
		ret = PTR_ERR(priv->sysclk);
		if (ret != -EPROBE_DEFER)
			dev_err(dev, "failed to get dclk: %d\n", ret);
		return ret;
	}

	return devm_snd_soc_register_component(dev, &axg_pdm_component_drv,
					       &axg_pdm_dai_drv, 1);
}

static struct platform_driver axg_pdm_pdrv = {
	.probe = axg_pdm_probe,
	.driver = {
		.name = "axg-pdm",
		.of_match_table = axg_pdm_of_match,
	},
};
module_platform_driver(axg_pdm_pdrv);

MODULE_DESCRIPTION("Amlogic AXG PDM Input driver");
MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
MODULE_LICENSE("GPL v2");