xref: /openbmc/linux/sound/soc/atmel/mchp-pdmc.c (revision 297ce026)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Driver for Microchip Pulse Density Microphone Controller (PDMC) interfaces
4 //
5 // Copyright (C) 2019-2022 Microchip Technology Inc. and its subsidiaries
6 //
7 // Author: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
8 
9 #include <dt-bindings/sound/microchip,pdmc.h>
10 
11 #include <linux/clk.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/regmap.h>
15 
16 #include <sound/core.h>
17 #include <sound/dmaengine_pcm.h>
18 #include <sound/pcm_params.h>
19 #include <sound/tlv.h>
20 
21 /*
22  * ---- PDMC Register map ----
23  */
24 #define MCHP_PDMC_CR			0x00	/* Control Register */
25 #define MCHP_PDMC_MR			0x04	/* Mode Register */
26 #define MCHP_PDMC_CFGR			0x08	/* Configuration Register */
27 #define MCHP_PDMC_RHR			0x0C	/* Receive Holding Register */
28 #define MCHP_PDMC_IER			0x14	/* Interrupt Enable Register */
29 #define MCHP_PDMC_IDR			0x18	/* Interrupt Disable Register */
30 #define MCHP_PDMC_IMR			0x1C	/* Interrupt Mask Register */
31 #define MCHP_PDMC_ISR			0x20	/* Interrupt Status Register */
32 #define MCHP_PDMC_VER			0x50	/* Version Register */
33 
34 /*
35  * ---- Control Register (Write-only) ----
36  */
37 #define MCHP_PDMC_CR_SWRST		BIT(0)	/* Software Reset */
38 
39 /*
40  * ---- Mode Register (Read/Write) ----
41  */
42 #define MCHP_PDMC_MR_PDMCEN_MASK	GENMASK(3, 0)
43 #define MCHP_PDMC_MR_PDMCEN(ch)		(BIT(ch) & MCHP_PDMC_MR_PDMCEN_MASK)
44 
45 #define MCHP_PDMC_MR_OSR_MASK		GENMASK(17, 16)
46 #define MCHP_PDMC_MR_OSR64		(1 << 16)
47 #define MCHP_PDMC_MR_OSR128		(2 << 16)
48 #define MCHP_PDMC_MR_OSR256		(3 << 16)
49 
50 #define MCHP_PDMC_MR_SINCORDER_MASK	GENMASK(23, 20)
51 #define MCHP_PDMC_MR_SINCORDER(order)	(((order) << 20) & \
52 					 MCHP_PDMC_MR_SINCORDER_MASK)
53 
54 #define MCHP_PDMC_MR_SINC_OSR_MASK	GENMASK(27, 24)
55 #define MCHP_PDMC_MR_SINC_OSR_DIS	(0 << 24)
56 #define MCHP_PDMC_MR_SINC_OSR_8		(1 << 24)
57 #define MCHP_PDMC_MR_SINC_OSR_16	(2 << 24)
58 #define MCHP_PDMC_MR_SINC_OSR_32	(3 << 24)
59 #define MCHP_PDMC_MR_SINC_OSR_64	(4 << 24)
60 #define MCHP_PDMC_MR_SINC_OSR_128	(5 << 24)
61 #define MCHP_PDMC_MR_SINC_OSR_256	(6 << 24)
62 
63 #define MCHP_PDMC_MR_CHUNK_MASK		GENMASK(31, 28)
64 #define MCHP_PDMC_MR_CHUNK(chunk)	(((chunk) << 28) & \
65 					 MCHP_PDMC_MR_CHUNK_MASK)
66 
67 /*
68  * ---- Configuration Register (Read/Write) ----
69  */
70 #define MCHP_PDMC_CFGR_BSSEL_MASK	(BIT(0) | BIT(2) | BIT(4) | BIT(6))
71 #define MCHP_PDMC_CFGR_BSSEL(ch)	BIT((ch) * 2)
72 
73 #define MCHP_PDMC_CFGR_PDMSEL_MASK	(BIT(16) | BIT(18) | BIT(20) | BIT(22))
74 #define MCHP_PDMC_CFGR_PDMSEL(ch)	BIT((ch) * 2 + 16)
75 
76 /*
77  * ---- Interrupt Enable/Disable/Mask/Status Registers ----
78  */
79 #define MCHP_PDMC_IR_RXRDY		BIT(0)
80 #define MCHP_PDMC_IR_RXEMPTY		BIT(1)
81 #define MCHP_PDMC_IR_RXFULL		BIT(2)
82 #define MCHP_PDMC_IR_RXCHUNK		BIT(3)
83 #define MCHP_PDMC_IR_RXUDR		BIT(4)
84 #define MCHP_PDMC_IR_RXOVR		BIT(5)
85 
86 /*
87  * ---- Version Register (Read-only) ----
88  */
89 #define MCHP_PDMC_VER_VERSION		GENMASK(11, 0)
90 
91 #define MCHP_PDMC_MAX_CHANNELS		4
92 #define MCHP_PDMC_DS_NO			2
93 #define MCHP_PDMC_EDGE_NO		2
94 
95 struct mic_map {
96 	int ds_pos;
97 	int clk_edge;
98 };
99 
100 struct mchp_pdmc_chmap {
101 	struct snd_pcm_chmap_elem *chmap;
102 	struct mchp_pdmc *dd;
103 	struct snd_pcm *pcm;
104 	struct snd_kcontrol *kctl;
105 };
106 
107 struct mchp_pdmc {
108 	struct mic_map channel_mic_map[MCHP_PDMC_MAX_CHANNELS];
109 	struct device *dev;
110 	struct snd_dmaengine_dai_dma_data addr;
111 	struct regmap *regmap;
112 	struct clk *pclk;
113 	struct clk *gclk;
114 	u32 pdmcen;
115 	int mic_no;
116 	int sinc_order;
117 	bool audio_filter_en;
118 	u8 gclk_enabled:1;
119 };
120 
121 static const char *const mchp_pdmc_sinc_filter_order_text[] = {
122 	"1", "2", "3", "4", "5"
123 };
124 
125 static const unsigned int mchp_pdmc_sinc_filter_order_values[] = {
126 	1, 2, 3, 4, 5,
127 };
128 
129 static const struct soc_enum mchp_pdmc_sinc_filter_order_enum = {
130 	.items = ARRAY_SIZE(mchp_pdmc_sinc_filter_order_text),
131 	.texts = mchp_pdmc_sinc_filter_order_text,
132 	.values = mchp_pdmc_sinc_filter_order_values,
133 };
134 
135 static int mchp_pdmc_sinc_order_get(struct snd_kcontrol *kcontrol,
136 				    struct snd_ctl_elem_value *uvalue)
137 {
138 	struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
139 	struct mchp_pdmc *dd = snd_soc_component_get_drvdata(component);
140 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
141 	unsigned int item;
142 
143 	item = snd_soc_enum_val_to_item(e, dd->sinc_order);
144 	uvalue->value.enumerated.item[0] = item;
145 
146 	return 0;
147 }
148 
149 static int mchp_pdmc_sinc_order_put(struct snd_kcontrol *kcontrol,
150 				    struct snd_ctl_elem_value *uvalue)
151 {
152 	struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
153 	struct mchp_pdmc *dd = snd_soc_component_get_drvdata(component);
154 	struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
155 	unsigned int *item = uvalue->value.enumerated.item;
156 	unsigned int val;
157 
158 	if (item[0] >= e->items)
159 		return -EINVAL;
160 
161 	val = snd_soc_enum_item_to_val(e, item[0]) << e->shift_l;
162 	if (val == dd->sinc_order)
163 		return 0;
164 
165 	dd->sinc_order = val;
166 
167 	return 1;
168 }
169 
170 static int mchp_pdmc_af_get(struct snd_kcontrol *kcontrol,
171 			    struct snd_ctl_elem_value *uvalue)
172 {
173 	struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
174 	struct mchp_pdmc *dd = snd_soc_component_get_drvdata(component);
175 
176 	uvalue->value.integer.value[0] = !!dd->audio_filter_en;
177 
178 	return 0;
179 }
180 
181 static int mchp_pdmc_af_put(struct snd_kcontrol *kcontrol,
182 			    struct snd_ctl_elem_value *uvalue)
183 {
184 	struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
185 	struct mchp_pdmc *dd = snd_soc_component_get_drvdata(component);
186 	bool af = uvalue->value.integer.value[0] ? true : false;
187 
188 	if (dd->audio_filter_en == af)
189 		return 0;
190 
191 	dd->audio_filter_en = af;
192 
193 	return 1;
194 }
195 
196 static int mchp_pdmc_chmap_ctl_info(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
197 {
198 	struct mchp_pdmc_chmap *info = snd_kcontrol_chip(kcontrol);
199 
200 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
201 	uinfo->count = info->dd->mic_no;
202 	uinfo->value.integer.min = 0;
203 	uinfo->value.integer.max = SNDRV_CHMAP_RR; /* maxmimum 4 channels */
204 	return 0;
205 }
206 
207 static inline struct snd_pcm_substream *
208 mchp_pdmc_chmap_substream(struct mchp_pdmc_chmap *info, unsigned int idx)
209 {
210 	struct snd_pcm_substream *s;
211 
212 	for (s = info->pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream; s; s = s->next)
213 		if (s->number == idx)
214 			return s;
215 	return NULL;
216 }
217 
218 static struct snd_pcm_chmap_elem *mchp_pdmc_chmap_get(struct snd_pcm_substream *substream,
219 						      struct mchp_pdmc_chmap *ch_info)
220 {
221 	struct snd_pcm_chmap_elem *map;
222 
223 	for (map = ch_info->chmap; map->channels; map++) {
224 		if (map->channels == substream->runtime->channels)
225 			return map;
226 	}
227 	return NULL;
228 }
229 
230 static int mchp_pdmc_chmap_ctl_get(struct snd_kcontrol *kcontrol,
231 				   struct snd_ctl_elem_value *ucontrol)
232 {
233 	struct mchp_pdmc_chmap *info = snd_kcontrol_chip(kcontrol);
234 	struct mchp_pdmc *dd = info->dd;
235 	unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
236 	struct snd_pcm_substream *substream;
237 	const struct snd_pcm_chmap_elem *map;
238 	int i;
239 	u32 cfgr_val = 0;
240 
241 	if (!info->chmap)
242 		return -EINVAL;
243 	substream = mchp_pdmc_chmap_substream(info, idx);
244 	if (!substream)
245 		return -ENODEV;
246 	memset(ucontrol->value.integer.value, 0, sizeof(long) * info->dd->mic_no);
247 	if (!substream->runtime)
248 		return 0; /* no channels set */
249 
250 	map = mchp_pdmc_chmap_get(substream, info);
251 	if (!map)
252 		return -EINVAL;
253 
254 	for (i = 0; i < map->channels; i++) {
255 		int map_idx = map->channels == 1 ? map->map[i] - SNDRV_CHMAP_MONO :
256 						   map->map[i] - SNDRV_CHMAP_FL;
257 
258 		/* make sure the reported channel map is the real one, so write the map */
259 		if (dd->channel_mic_map[map_idx].ds_pos)
260 			cfgr_val |= MCHP_PDMC_CFGR_PDMSEL(i);
261 		if (dd->channel_mic_map[map_idx].clk_edge)
262 			cfgr_val |= MCHP_PDMC_CFGR_BSSEL(i);
263 
264 		ucontrol->value.integer.value[i] = map->map[i];
265 	}
266 
267 	regmap_write(dd->regmap, MCHP_PDMC_CFGR, cfgr_val);
268 
269 	return 0;
270 }
271 
272 static int mchp_pdmc_chmap_ctl_put(struct snd_kcontrol *kcontrol,
273 				   struct snd_ctl_elem_value *ucontrol)
274 {
275 	struct mchp_pdmc_chmap *info = snd_kcontrol_chip(kcontrol);
276 	struct mchp_pdmc *dd = info->dd;
277 	unsigned int idx = snd_ctl_get_ioffidx(kcontrol, &ucontrol->id);
278 	struct snd_pcm_substream *substream;
279 	struct snd_pcm_chmap_elem *map;
280 	u32 cfgr_val = 0;
281 	int i;
282 
283 	if (!info->chmap)
284 		return -EINVAL;
285 	substream = mchp_pdmc_chmap_substream(info, idx);
286 	if (!substream)
287 		return -ENODEV;
288 
289 	map = mchp_pdmc_chmap_get(substream, info);
290 	if (!map)
291 		return -EINVAL;
292 
293 	for (i = 0; i < map->channels; i++) {
294 		int map_idx;
295 
296 		map->map[i] = ucontrol->value.integer.value[i];
297 		map_idx = map->channels == 1 ? map->map[i] - SNDRV_CHMAP_MONO :
298 					       map->map[i] - SNDRV_CHMAP_FL;
299 
300 		/* configure IP for the desired channel map */
301 		if (dd->channel_mic_map[map_idx].ds_pos)
302 			cfgr_val |= MCHP_PDMC_CFGR_PDMSEL(i);
303 		if (dd->channel_mic_map[map_idx].clk_edge)
304 			cfgr_val |= MCHP_PDMC_CFGR_BSSEL(i);
305 	}
306 
307 	regmap_write(dd->regmap, MCHP_PDMC_CFGR, cfgr_val);
308 
309 	return 0;
310 }
311 
312 static void mchp_pdmc_chmap_ctl_private_free(struct snd_kcontrol *kcontrol)
313 {
314 	struct mchp_pdmc_chmap *info = snd_kcontrol_chip(kcontrol);
315 
316 	info->pcm->streams[SNDRV_PCM_STREAM_CAPTURE].chmap_kctl = NULL;
317 	kfree(info);
318 }
319 
320 static int mchp_pdmc_chmap_ctl_tlv(struct snd_kcontrol *kcontrol, int op_flag,
321 				   unsigned int size, unsigned int __user *tlv)
322 {
323 	struct mchp_pdmc_chmap *info = snd_kcontrol_chip(kcontrol);
324 	const struct snd_pcm_chmap_elem *map;
325 	unsigned int __user *dst;
326 	int c, count = 0;
327 
328 	if (!info->chmap)
329 		return -EINVAL;
330 	if (size < 8)
331 		return -ENOMEM;
332 	if (put_user(SNDRV_CTL_TLVT_CONTAINER, tlv))
333 		return -EFAULT;
334 	size -= 8;
335 	dst = tlv + 2;
336 	for (map = info->chmap; map->channels; map++) {
337 		int chs_bytes = map->channels * 4;
338 
339 		if (size < 8)
340 			return -ENOMEM;
341 		if (put_user(SNDRV_CTL_TLVT_CHMAP_VAR, dst) ||
342 		    put_user(chs_bytes, dst + 1))
343 			return -EFAULT;
344 		dst += 2;
345 		size -= 8;
346 		count += 8;
347 		if (size < chs_bytes)
348 			return -ENOMEM;
349 		size -= chs_bytes;
350 		count += chs_bytes;
351 		for (c = 0; c < map->channels; c++) {
352 			if (put_user(map->map[c], dst))
353 				return -EFAULT;
354 			dst++;
355 		}
356 	}
357 	if (put_user(count, tlv + 1))
358 		return -EFAULT;
359 	return 0;
360 }
361 
362 static const struct snd_kcontrol_new mchp_pdmc_snd_controls[] = {
363 	SOC_SINGLE_BOOL_EXT("Audio Filter", 0, &mchp_pdmc_af_get, &mchp_pdmc_af_put),
364 	{
365 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
366 		.name = "SINC Filter Order",
367 		.info = snd_soc_info_enum_double,
368 		.get = mchp_pdmc_sinc_order_get,
369 		.put = mchp_pdmc_sinc_order_put,
370 		.private_value = (unsigned long)&mchp_pdmc_sinc_filter_order_enum,
371 	},
372 };
373 
374 static int mchp_pdmc_close(struct snd_soc_component *component,
375 			   struct snd_pcm_substream *substream)
376 {
377 	return snd_soc_add_component_controls(component, mchp_pdmc_snd_controls,
378 					      ARRAY_SIZE(mchp_pdmc_snd_controls));
379 }
380 
381 static int mchp_pdmc_open(struct snd_soc_component *component,
382 			  struct snd_pcm_substream *substream)
383 {
384 	int i;
385 
386 	/* remove controls that can't be changed at runtime */
387 	for (i = 0; i < ARRAY_SIZE(mchp_pdmc_snd_controls); i++) {
388 		const struct snd_kcontrol_new *control = &mchp_pdmc_snd_controls[i];
389 		struct snd_ctl_elem_id id;
390 		struct snd_kcontrol *kctl;
391 		int err;
392 
393 		if (component->name_prefix)
394 			snprintf(id.name, sizeof(id.name), "%s %s", component->name_prefix,
395 				 control->name);
396 		else
397 			strscpy(id.name, control->name, sizeof(id.name));
398 
399 		id.numid = 0;
400 		id.iface = control->iface;
401 		id.device = control->device;
402 		id.subdevice = control->subdevice;
403 		id.index = control->index;
404 		kctl = snd_ctl_find_id(component->card->snd_card, &id);
405 		if (!kctl) {
406 			dev_err(component->dev, "Failed to find %s\n", control->name);
407 			continue;
408 		}
409 		err = snd_ctl_remove(component->card->snd_card, kctl);
410 		if (err < 0) {
411 			dev_err(component->dev, "%d: Failed to remove %s\n", err,
412 				control->name);
413 			continue;
414 		}
415 	}
416 
417 	return 0;
418 }
419 
420 static const struct snd_soc_component_driver mchp_pdmc_dai_component = {
421 	.name = "mchp-pdmc",
422 	.controls = mchp_pdmc_snd_controls,
423 	.num_controls = ARRAY_SIZE(mchp_pdmc_snd_controls),
424 	.open = &mchp_pdmc_open,
425 	.close = &mchp_pdmc_close,
426 };
427 
428 static const unsigned int mchp_pdmc_1mic[] = {1};
429 static const unsigned int mchp_pdmc_2mic[] = {1, 2};
430 static const unsigned int mchp_pdmc_3mic[] = {1, 2, 3};
431 static const unsigned int mchp_pdmc_4mic[] = {1, 2, 3, 4};
432 
433 static const struct snd_pcm_hw_constraint_list mchp_pdmc_chan_constr[] = {
434 	{
435 		.list = mchp_pdmc_1mic,
436 		.count = ARRAY_SIZE(mchp_pdmc_1mic),
437 	},
438 	{
439 		.list = mchp_pdmc_2mic,
440 		.count = ARRAY_SIZE(mchp_pdmc_2mic),
441 	},
442 	{
443 		.list = mchp_pdmc_3mic,
444 		.count = ARRAY_SIZE(mchp_pdmc_3mic),
445 	},
446 	{
447 		.list = mchp_pdmc_4mic,
448 		.count = ARRAY_SIZE(mchp_pdmc_4mic),
449 	},
450 };
451 
452 static int mchp_pdmc_startup(struct snd_pcm_substream *substream,
453 			     struct snd_soc_dai *dai)
454 {
455 	struct mchp_pdmc *dd = snd_soc_dai_get_drvdata(dai);
456 	int ret;
457 
458 	ret = clk_prepare_enable(dd->pclk);
459 	if (ret) {
460 		dev_err(dd->dev, "failed to enable the peripheral clock: %d\n", ret);
461 		return ret;
462 	}
463 
464 	regmap_write(dd->regmap, MCHP_PDMC_CR, MCHP_PDMC_CR_SWRST);
465 
466 	snd_pcm_hw_constraint_list(substream->runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
467 				   &mchp_pdmc_chan_constr[dd->mic_no - 1]);
468 
469 	return 0;
470 }
471 
472 static void mchp_pdmc_shutdown(struct snd_pcm_substream *substream,
473 			       struct snd_soc_dai *dai)
474 {
475 	struct mchp_pdmc *dd = snd_soc_dai_get_drvdata(dai);
476 
477 	clk_disable_unprepare(dd->pclk);
478 }
479 
480 static int mchp_pdmc_dai_probe(struct snd_soc_dai *dai)
481 {
482 	struct mchp_pdmc *dd = snd_soc_dai_get_drvdata(dai);
483 
484 	snd_soc_dai_init_dma_data(dai, NULL, &dd->addr);
485 
486 	return 0;
487 }
488 
489 static int mchp_pdmc_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
490 {
491 	unsigned int fmt_master = fmt & SND_SOC_DAIFMT_MASTER_MASK;
492 	unsigned int fmt_format = fmt & SND_SOC_DAIFMT_FORMAT_MASK;
493 
494 	/* IP needs to be bitclock master */
495 	if (fmt_master != SND_SOC_DAIFMT_CBS_CFS &&
496 	    fmt_master != SND_SOC_DAIFMT_CBS_CFM)
497 		return -EINVAL;
498 
499 	/* IP supports only PDM interface */
500 	if (fmt_format != SND_SOC_DAIFMT_PDM)
501 		return -EINVAL;
502 
503 	return 0;
504 }
505 
506 static u32 mchp_pdmc_mr_set_osr(int audio_filter_en, unsigned int osr)
507 {
508 	if (audio_filter_en) {
509 		switch (osr) {
510 		case 64:
511 			return MCHP_PDMC_MR_OSR64;
512 		case 128:
513 			return MCHP_PDMC_MR_OSR128;
514 		case 256:
515 			return MCHP_PDMC_MR_OSR256;
516 		}
517 	} else {
518 		switch (osr) {
519 		case 8:
520 			return MCHP_PDMC_MR_SINC_OSR_8;
521 		case 16:
522 			return MCHP_PDMC_MR_SINC_OSR_16;
523 		case 32:
524 			return MCHP_PDMC_MR_SINC_OSR_32;
525 		case 64:
526 			return MCHP_PDMC_MR_SINC_OSR_64;
527 		case 128:
528 			return MCHP_PDMC_MR_SINC_OSR_128;
529 		case 256:
530 			return MCHP_PDMC_MR_SINC_OSR_256;
531 		}
532 	}
533 	return 0;
534 }
535 
536 static inline int mchp_pdmc_period_to_maxburst(int period_size)
537 {
538 	if (!(period_size % 8))
539 		return 8;
540 	if (!(period_size % 4))
541 		return 4;
542 	if (!(period_size % 2))
543 		return 2;
544 	return 1;
545 }
546 
547 static struct snd_pcm_chmap_elem mchp_pdmc_std_chmaps[] = {
548 	{ .channels = 1,
549 	  .map = { SNDRV_CHMAP_MONO } },
550 	{ .channels = 2,
551 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
552 	{ .channels = 3,
553 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
554 		   SNDRV_CHMAP_RL } },
555 	{ .channels = 4,
556 	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR,
557 		   SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
558 	{ }
559 };
560 
561 static int mchp_pdmc_hw_params(struct snd_pcm_substream *substream,
562 			       struct snd_pcm_hw_params *params,
563 			       struct snd_soc_dai *dai)
564 {
565 	struct mchp_pdmc *dd = snd_soc_dai_get_drvdata(dai);
566 	struct snd_soc_component *comp = dai->component;
567 	unsigned long gclk_rate = 0;
568 	unsigned long best_diff_rate = ~0UL;
569 	unsigned int channels = params_channels(params);
570 	unsigned int osr = 0, osr_start;
571 	unsigned int fs = params_rate(params);
572 	u32 mr_val = 0;
573 	u32 cfgr_val = 0;
574 	int i;
575 	int ret;
576 
577 	dev_dbg(comp->dev, "%s() rate=%u format=%#x width=%u channels=%u\n",
578 		__func__, params_rate(params), params_format(params),
579 		params_width(params), params_channels(params));
580 
581 	if (channels > dd->mic_no) {
582 		dev_err(comp->dev, "more channels %u than microphones %d\n",
583 			channels, dd->mic_no);
584 		return -EINVAL;
585 	}
586 
587 	dd->pdmcen = 0;
588 	for (i = 0; i < channels; i++) {
589 		dd->pdmcen |= MCHP_PDMC_MR_PDMCEN(i);
590 		if (dd->channel_mic_map[i].ds_pos)
591 			cfgr_val |= MCHP_PDMC_CFGR_PDMSEL(i);
592 		if (dd->channel_mic_map[i].clk_edge)
593 			cfgr_val |= MCHP_PDMC_CFGR_BSSEL(i);
594 	}
595 
596 	if (dd->gclk_enabled) {
597 		clk_disable_unprepare(dd->gclk);
598 		dd->gclk_enabled = 0;
599 	}
600 
601 	for (osr_start = dd->audio_filter_en ? 64 : 8;
602 	     osr_start <= 256 && best_diff_rate; osr_start *= 2) {
603 		long round_rate;
604 		unsigned long diff_rate;
605 
606 		round_rate = clk_round_rate(dd->gclk,
607 					    (unsigned long)fs * 16 * osr_start);
608 		if (round_rate < 0)
609 			continue;
610 		diff_rate = abs((fs * 16 * osr_start) - round_rate);
611 		if (diff_rate < best_diff_rate) {
612 			best_diff_rate = diff_rate;
613 			osr = osr_start;
614 			gclk_rate = fs * 16 * osr;
615 		}
616 	}
617 	if (!gclk_rate) {
618 		dev_err(comp->dev, "invalid sampling rate: %u\n", fs);
619 		return -EINVAL;
620 	}
621 
622 	/* set the rate */
623 	ret = clk_set_rate(dd->gclk, gclk_rate);
624 	if (ret) {
625 		dev_err(comp->dev, "unable to set rate %lu to GCLK: %d\n",
626 			gclk_rate, ret);
627 		return ret;
628 	}
629 
630 	mr_val |= mchp_pdmc_mr_set_osr(dd->audio_filter_en, osr);
631 
632 	mr_val |= MCHP_PDMC_MR_SINCORDER(dd->sinc_order);
633 
634 	dd->addr.maxburst = mchp_pdmc_period_to_maxburst(snd_pcm_lib_period_bytes(substream));
635 	mr_val |= MCHP_PDMC_MR_CHUNK(dd->addr.maxburst);
636 	dev_dbg(comp->dev, "maxburst set to %d\n", dd->addr.maxburst);
637 
638 	clk_prepare_enable(dd->gclk);
639 	dd->gclk_enabled = 1;
640 
641 	snd_soc_component_update_bits(comp, MCHP_PDMC_MR,
642 				      MCHP_PDMC_MR_OSR_MASK |
643 				      MCHP_PDMC_MR_SINCORDER_MASK |
644 				      MCHP_PDMC_MR_SINC_OSR_MASK |
645 				      MCHP_PDMC_MR_CHUNK_MASK, mr_val);
646 
647 	snd_soc_component_write(comp, MCHP_PDMC_CFGR, cfgr_val);
648 
649 	return 0;
650 }
651 
652 static int mchp_pdmc_hw_free(struct snd_pcm_substream *substream,
653 			     struct snd_soc_dai *dai)
654 {
655 	struct mchp_pdmc *dd = snd_soc_dai_get_drvdata(dai);
656 
657 	if (dd->gclk_enabled) {
658 		clk_disable_unprepare(dd->gclk);
659 		dd->gclk_enabled = 0;
660 	}
661 
662 	return 0;
663 }
664 
665 static int mchp_pdmc_trigger(struct snd_pcm_substream *substream,
666 			     int cmd, struct snd_soc_dai *dai)
667 {
668 	struct mchp_pdmc *dd = snd_soc_dai_get_drvdata(dai);
669 	struct snd_soc_component *cpu = dai->component;
670 #ifdef DEBUG
671 	u32 val;
672 #endif
673 
674 	switch (cmd) {
675 	case SNDRV_PCM_TRIGGER_START:
676 	case SNDRV_PCM_TRIGGER_RESUME:
677 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
678 		/* Enable overrun and underrun error interrupts */
679 		regmap_write(dd->regmap, MCHP_PDMC_IER,
680 			     MCHP_PDMC_IR_RXOVR | MCHP_PDMC_IR_RXUDR);
681 		snd_soc_component_update_bits(cpu, MCHP_PDMC_MR,
682 					      MCHP_PDMC_MR_PDMCEN_MASK,
683 					      dd->pdmcen);
684 		break;
685 	case SNDRV_PCM_TRIGGER_STOP:
686 	case SNDRV_PCM_TRIGGER_SUSPEND:
687 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
688 		/* Disable overrun and underrun error interrupts */
689 		regmap_write(dd->regmap, MCHP_PDMC_IDR,
690 			     MCHP_PDMC_IR_RXOVR | MCHP_PDMC_IR_RXUDR);
691 		snd_soc_component_update_bits(cpu, MCHP_PDMC_MR,
692 					      MCHP_PDMC_MR_PDMCEN_MASK, 0);
693 		break;
694 	default:
695 		return -EINVAL;
696 	}
697 
698 #ifdef DEBUG
699 	regmap_read(dd->regmap, MCHP_PDMC_MR, &val);
700 	dev_dbg(dd->dev, "MR (0x%02x): 0x%08x\n", MCHP_PDMC_MR, val);
701 	regmap_read(dd->regmap, MCHP_PDMC_CFGR, &val);
702 	dev_dbg(dd->dev, "CFGR (0x%02x): 0x%08x\n", MCHP_PDMC_CFGR, val);
703 	regmap_read(dd->regmap, MCHP_PDMC_IMR, &val);
704 	dev_dbg(dd->dev, "IMR (0x%02x): 0x%08x\n", MCHP_PDMC_IMR, val);
705 #endif
706 
707 	return 0;
708 }
709 
710 static const struct snd_soc_dai_ops mchp_pdmc_dai_ops = {
711 	.set_fmt	= mchp_pdmc_set_fmt,
712 	.startup	= mchp_pdmc_startup,
713 	.shutdown	= mchp_pdmc_shutdown,
714 	.hw_params	= mchp_pdmc_hw_params,
715 	.hw_free	= mchp_pdmc_hw_free,
716 	.trigger	= mchp_pdmc_trigger,
717 };
718 
719 static int mchp_pdmc_add_chmap_ctls(struct snd_pcm *pcm, struct mchp_pdmc *dd)
720 {
721 	struct mchp_pdmc_chmap *info;
722 	struct snd_kcontrol_new knew = {
723 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
724 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
725 			SNDRV_CTL_ELEM_ACCESS_TLV_READ |
726 			SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK,
727 		.info = mchp_pdmc_chmap_ctl_info,
728 		.get = mchp_pdmc_chmap_ctl_get,
729 		.put = mchp_pdmc_chmap_ctl_put,
730 		.tlv.c = mchp_pdmc_chmap_ctl_tlv,
731 	};
732 	int err;
733 
734 	if (WARN_ON(pcm->streams[SNDRV_PCM_STREAM_CAPTURE].chmap_kctl))
735 		return -EBUSY;
736 	info = kzalloc(sizeof(*info), GFP_KERNEL);
737 	if (!info)
738 		return -ENOMEM;
739 	info->pcm = pcm;
740 	info->dd = dd;
741 	info->chmap = mchp_pdmc_std_chmaps;
742 	knew.name = "Capture Channel Map";
743 	knew.device = pcm->device;
744 	knew.count = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream_count;
745 	info->kctl = snd_ctl_new1(&knew, info);
746 	if (!info->kctl) {
747 		kfree(info);
748 		return -ENOMEM;
749 	}
750 	info->kctl->private_free = mchp_pdmc_chmap_ctl_private_free;
751 	err = snd_ctl_add(pcm->card, info->kctl);
752 	if (err < 0)
753 		return err;
754 	pcm->streams[SNDRV_PCM_STREAM_CAPTURE].chmap_kctl = info->kctl;
755 	return 0;
756 }
757 
758 static int mchp_pdmc_pcm_new(struct snd_soc_pcm_runtime *rtd,
759 			     struct snd_soc_dai *dai)
760 {
761 	struct mchp_pdmc *dd = snd_soc_dai_get_drvdata(dai);
762 	int ret;
763 
764 	ret = mchp_pdmc_add_chmap_ctls(rtd->pcm, dd);
765 	if (ret < 0) {
766 		dev_err(dd->dev, "failed to add channel map controls: %d\n", ret);
767 		return ret;
768 	}
769 
770 	return 0;
771 }
772 
773 static struct snd_soc_dai_driver mchp_pdmc_dai = {
774 	.probe	= mchp_pdmc_dai_probe,
775 	.capture = {
776 		.stream_name	= "Capture",
777 		.channels_min	= 1,
778 		.channels_max	= 4,
779 		.rate_min	= 8000,
780 		.rate_max	= 192000,
781 		.rates		= SNDRV_PCM_RATE_KNOT,
782 		.formats	= SNDRV_PCM_FMTBIT_S24_LE,
783 	},
784 	.ops = &mchp_pdmc_dai_ops,
785 	.pcm_new = &mchp_pdmc_pcm_new,
786 };
787 
788 /* PDMC interrupt handler */
789 static irqreturn_t mchp_pdmc_interrupt(int irq, void *dev_id)
790 {
791 	struct mchp_pdmc *dd = (struct mchp_pdmc *)dev_id;
792 	u32 isr, msr, pending;
793 	irqreturn_t ret = IRQ_NONE;
794 
795 	regmap_read(dd->regmap, MCHP_PDMC_ISR, &isr);
796 	regmap_read(dd->regmap, MCHP_PDMC_IMR, &msr);
797 
798 	pending = isr & msr;
799 	dev_dbg(dd->dev, "ISR (0x%02x): 0x%08x, IMR (0x%02x): 0x%08x, pending: 0x%08x\n",
800 		MCHP_PDMC_ISR, isr, MCHP_PDMC_IMR, msr, pending);
801 	if (!pending)
802 		return IRQ_NONE;
803 
804 	if (pending & MCHP_PDMC_IR_RXUDR) {
805 		dev_warn(dd->dev, "underrun detected\n");
806 		regmap_write(dd->regmap, MCHP_PDMC_IDR, MCHP_PDMC_IR_RXUDR);
807 		ret = IRQ_HANDLED;
808 	}
809 	if (pending & MCHP_PDMC_IR_RXOVR) {
810 		dev_warn(dd->dev, "overrun detected\n");
811 		regmap_write(dd->regmap, MCHP_PDMC_IDR, MCHP_PDMC_IR_RXOVR);
812 		ret = IRQ_HANDLED;
813 	}
814 
815 	return ret;
816 }
817 
818 /* regmap configuration */
819 static bool mchp_pdmc_readable_reg(struct device *dev, unsigned int reg)
820 {
821 	switch (reg) {
822 	case MCHP_PDMC_MR:
823 	case MCHP_PDMC_CFGR:
824 	case MCHP_PDMC_IMR:
825 	case MCHP_PDMC_ISR:
826 	case MCHP_PDMC_VER:
827 		return true;
828 	default:
829 		return false;
830 	}
831 }
832 
833 static bool mchp_pdmc_writeable_reg(struct device *dev, unsigned int reg)
834 {
835 	switch (reg) {
836 	case MCHP_PDMC_CR:
837 	case MCHP_PDMC_MR:
838 	case MCHP_PDMC_CFGR:
839 	case MCHP_PDMC_IER:
840 	case MCHP_PDMC_IDR:
841 		return true;
842 	default:
843 		return false;
844 	}
845 }
846 
847 static bool mchp_pdmc_precious_reg(struct device *dev, unsigned int reg)
848 {
849 	switch (reg) {
850 	case MCHP_PDMC_RHR:
851 	case MCHP_PDMC_ISR:
852 		return true;
853 	default:
854 		return false;
855 	}
856 }
857 
858 static const struct regmap_config mchp_pdmc_regmap_config = {
859 	.reg_bits	= 32,
860 	.reg_stride	= 4,
861 	.val_bits	= 32,
862 	.max_register	= MCHP_PDMC_VER,
863 	.readable_reg	= mchp_pdmc_readable_reg,
864 	.writeable_reg	= mchp_pdmc_writeable_reg,
865 	.precious_reg	= mchp_pdmc_precious_reg,
866 };
867 
868 static int mchp_pdmc_dt_init(struct mchp_pdmc *dd)
869 {
870 	struct device_node *np = dd->dev->of_node;
871 	bool mic_ch[MCHP_PDMC_DS_NO][MCHP_PDMC_EDGE_NO] = {0};
872 	int i;
873 	int ret;
874 
875 	if (!np) {
876 		dev_err(dd->dev, "device node not found\n");
877 		return -EINVAL;
878 	}
879 
880 	dd->mic_no = of_property_count_u32_elems(np, "microchip,mic-pos");
881 	if (dd->mic_no < 0) {
882 		dev_err(dd->dev, "failed to get microchip,mic-pos: %d",
883 			dd->mic_no);
884 		return dd->mic_no;
885 	}
886 	if (!dd->mic_no || dd->mic_no % 2 ||
887 	    dd->mic_no / 2 > MCHP_PDMC_MAX_CHANNELS) {
888 		dev_err(dd->dev, "invalid array length for microchip,mic-pos: %d",
889 			dd->mic_no);
890 		return -EINVAL;
891 	}
892 
893 	dd->mic_no /= 2;
894 
895 	dev_info(dd->dev, "%d PDM microphones declared\n", dd->mic_no);
896 
897 	/*
898 	 * by default, we consider the order of microphones in
899 	 * microchip,mic-pos to be the same with the channel mapping;
900 	 * 1st microphone channel 0, 2nd microphone channel 1, etc.
901 	 */
902 	for (i = 0; i < dd->mic_no; i++) {
903 		int ds;
904 		int edge;
905 
906 		ret = of_property_read_u32_index(np, "microchip,mic-pos", i * 2,
907 						 &ds);
908 		if (ret) {
909 			dev_err(dd->dev,
910 				"failed to get value no %d value from microchip,mic-pos: %d",
911 				i * 2, ret);
912 			return ret;
913 		}
914 		if (ds >= MCHP_PDMC_DS_NO) {
915 			dev_err(dd->dev,
916 				"invalid DS index in microchip,mic-pos array: %d",
917 				ds);
918 			return -EINVAL;
919 		}
920 
921 		ret = of_property_read_u32_index(np, "microchip,mic-pos", i * 2 + 1,
922 						 &edge);
923 		if (ret) {
924 			dev_err(dd->dev,
925 				"failed to get value no %d value from microchip,mic-pos: %d",
926 				i * 2 + 1, ret);
927 			return ret;
928 		}
929 
930 		if (edge != MCHP_PDMC_CLK_POSITIVE &&
931 		    edge != MCHP_PDMC_CLK_NEGATIVE) {
932 			dev_err(dd->dev,
933 				"invalid edge in microchip,mic-pos array: %d", edge);
934 			return -EINVAL;
935 		}
936 		if (mic_ch[ds][edge]) {
937 			dev_err(dd->dev,
938 				"duplicated mic (DS %d, edge %d) in microchip,mic-pos array",
939 				ds, edge);
940 			return -EINVAL;
941 		}
942 		mic_ch[ds][edge] = true;
943 		dd->channel_mic_map[i].ds_pos = ds;
944 		dd->channel_mic_map[i].clk_edge = edge;
945 	}
946 
947 	return 0;
948 }
949 
950 /* used to clean the channel index found on RHR's MSB */
951 static int mchp_pdmc_process(struct snd_pcm_substream *substream,
952 			     int channel, unsigned long hwoff,
953 			     void *buf, unsigned long bytes)
954 {
955 	struct snd_pcm_runtime *runtime = substream->runtime;
956 	u8 *dma_ptr = runtime->dma_area + hwoff +
957 		      channel * (runtime->dma_bytes / runtime->channels);
958 	u8 *dma_ptr_end = dma_ptr + bytes;
959 	unsigned int sample_size = samples_to_bytes(runtime, 1);
960 
961 	for (; dma_ptr < dma_ptr_end; dma_ptr += sample_size)
962 		*dma_ptr = 0;
963 
964 	return 0;
965 }
966 
967 static struct snd_dmaengine_pcm_config mchp_pdmc_config = {
968 	.process = mchp_pdmc_process,
969 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
970 };
971 
972 static int mchp_pdmc_probe(struct platform_device *pdev)
973 {
974 	struct device *dev = &pdev->dev;
975 	struct mchp_pdmc *dd;
976 	struct resource *res;
977 	void __iomem *io_base;
978 	u32 version;
979 	int irq;
980 	int ret;
981 
982 	dd = devm_kzalloc(dev, sizeof(*dd), GFP_KERNEL);
983 	if (!dd)
984 		return -ENOMEM;
985 
986 	dd->dev = &pdev->dev;
987 	ret =  mchp_pdmc_dt_init(dd);
988 	if (ret < 0)
989 		return ret;
990 
991 	irq = platform_get_irq(pdev, 0);
992 	if (irq < 0)
993 		return irq;
994 
995 	dd->pclk = devm_clk_get(dev, "pclk");
996 	if (IS_ERR(dd->pclk)) {
997 		ret = PTR_ERR(dd->pclk);
998 		dev_err(dev, "failed to get peripheral clock: %d\n", ret);
999 		return ret;
1000 	}
1001 
1002 	dd->gclk = devm_clk_get(dev, "gclk");
1003 	if (IS_ERR(dd->gclk)) {
1004 		ret = PTR_ERR(dd->gclk);
1005 		dev_err(dev, "failed to get GCK: %d\n", ret);
1006 		return ret;
1007 	}
1008 
1009 	io_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1010 	if (IS_ERR(io_base)) {
1011 		ret = PTR_ERR(io_base);
1012 		dev_err(dev, "failed to remap register memory: %d\n", ret);
1013 		return ret;
1014 	}
1015 
1016 	dd->regmap = devm_regmap_init_mmio(dev, io_base,
1017 					   &mchp_pdmc_regmap_config);
1018 	if (IS_ERR(dd->regmap)) {
1019 		ret = PTR_ERR(dd->regmap);
1020 		dev_err(dev, "failed to init register map: %d\n", ret);
1021 		return ret;
1022 	}
1023 
1024 	ret = devm_request_irq(dev, irq, mchp_pdmc_interrupt, 0,
1025 			       dev_name(&pdev->dev), (void *)dd);
1026 	if (ret < 0) {
1027 		dev_err(dev, "can't register ISR for IRQ %u (ret=%i)\n",
1028 			irq, ret);
1029 		return ret;
1030 	}
1031 
1032 	/* by default audio filter is enabled and the SINC Filter order
1033 	 * will be set to the recommended value, 3
1034 	 */
1035 	dd->audio_filter_en = true;
1036 	dd->sinc_order = 3;
1037 
1038 	dd->addr.addr = (dma_addr_t)res->start + MCHP_PDMC_RHR;
1039 	platform_set_drvdata(pdev, dd);
1040 
1041 	/* register platform */
1042 	ret = devm_snd_dmaengine_pcm_register(dev, &mchp_pdmc_config, 0);
1043 	if (ret) {
1044 		dev_err(dev, "could not register platform: %d\n", ret);
1045 		return ret;
1046 	}
1047 
1048 	ret = devm_snd_soc_register_component(dev, &mchp_pdmc_dai_component,
1049 					      &mchp_pdmc_dai, 1);
1050 	if (ret) {
1051 		dev_err(dev, "could not register CPU DAI: %d\n", ret);
1052 		return ret;
1053 	}
1054 
1055 	/* print IP version */
1056 	regmap_read(dd->regmap, MCHP_PDMC_VER, &version);
1057 	dev_info(dd->dev, "hw version: %#lx\n",
1058 		 version & MCHP_PDMC_VER_VERSION);
1059 
1060 	return 0;
1061 }
1062 
1063 static const struct of_device_id mchp_pdmc_of_match[] = {
1064 	{
1065 		.compatible = "microchip,sama7g5-pdmc",
1066 	}, {
1067 		/* sentinel */
1068 	}
1069 };
1070 MODULE_DEVICE_TABLE(of, mchp_pdmc_of_match);
1071 
1072 static struct platform_driver mchp_pdmc_driver = {
1073 	.driver	= {
1074 		.name		= "mchp-pdmc",
1075 		.of_match_table	= of_match_ptr(mchp_pdmc_of_match),
1076 		.pm		= &snd_soc_pm_ops,
1077 	},
1078 	.probe	= mchp_pdmc_probe,
1079 };
1080 module_platform_driver(mchp_pdmc_driver);
1081 
1082 MODULE_DESCRIPTION("Microchip PDMC driver under ALSA SoC architecture");
1083 MODULE_AUTHOR("Codrin Ciubotariu <codrin.ciubotariu@microchip.com>");
1084 MODULE_LICENSE("GPL v2");
1085