1// SPDX-License-Identifier: GPL-2.0
2//
3// Driver for Microchip S/PDIF TX Controller
4//
5// Copyright (C) 2020 Microchip Technology Inc. and its subsidiaries
6//
7// Author: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
8
9#include <linux/bitfield.h>
10#include <linux/clk.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/pm_runtime.h>
14#include <linux/spinlock.h>
15
16#include <sound/asoundef.h>
17#include <sound/dmaengine_pcm.h>
18#include <sound/pcm_params.h>
19#include <sound/soc.h>
20
21/*
22 * ---- S/PDIF Transmitter Controller Register map ----
23 */
24#define SPDIFTX_CR			0x00	/* Control Register */
25#define SPDIFTX_MR			0x04	/* Mode Register */
26#define SPDIFTX_CDR			0x0C	/* Common Data Register */
27
28#define SPDIFTX_IER			0x14	/* Interrupt Enable Register */
29#define SPDIFTX_IDR			0x18	/* Interrupt Disable Register */
30#define SPDIFTX_IMR			0x1C	/* Interrupt Mask Register */
31#define SPDIFTX_ISR			0x20	/* Interrupt Status Register */
32
33#define SPDIFTX_CH1UD(reg)	(0x50 + (reg) * 4)	/* User Data 1 Register x */
34#define SPDIFTX_CH1S(reg)	(0x80 + (reg) * 4)	/* Channel Status 1 Register x */
35
36#define SPDIFTX_VERSION			0xF0
37
38/*
39 * ---- Control Register (Write-only) ----
40 */
41#define SPDIFTX_CR_SWRST		BIT(0)	/* Software Reset */
42#define SPDIFTX_CR_FCLR			BIT(1)	/* FIFO clear */
43
44/*
45 * ---- Mode Register (Read/Write) ----
46 */
47/* Transmit Enable */
48#define SPDIFTX_MR_TXEN_MASK		GENMASK(0, 0)
49#define SPDIFTX_MR_TXEN_DISABLE		(0 << 0)
50#define SPDIFTX_MR_TXEN_ENABLE		(1 << 0)
51
52/* Multichannel Transfer */
53#define SPDIFTX_MR_MULTICH_MASK		GENAMSK(1, 1)
54#define SPDIFTX_MR_MULTICH_MONO		(0 << 1)
55#define SPDIFTX_MR_MULTICH_DUAL		(1 << 1)
56
57/* Data Word Endian Mode */
58#define SPDIFTX_MR_ENDIAN_MASK		GENMASK(2, 2)
59#define SPDIFTX_MR_ENDIAN_LITTLE	(0 << 2)
60#define SPDIFTX_MR_ENDIAN_BIG		(1 << 2)
61
62/* Data Justification */
63#define SPDIFTX_MR_JUSTIFY_MASK		GENMASK(3, 3)
64#define SPDIFTX_MR_JUSTIFY_LSB		(0 << 3)
65#define SPDIFTX_MR_JUSTIFY_MSB		(1 << 3)
66
67/* Common Audio Register Transfer Mode */
68#define SPDIFTX_MR_CMODE_MASK			GENMASK(5, 4)
69#define SPDIFTX_MR_CMODE_INDEX_ACCESS		(0 << 4)
70#define SPDIFTX_MR_CMODE_TOGGLE_ACCESS		(1 << 4)
71#define SPDIFTX_MR_CMODE_INTERLVD_ACCESS	(2 << 4)
72
73/* Valid Bits per Sample */
74#define SPDIFTX_MR_VBPS_MASK		GENMASK(13, 8)
75
76/* Chunk Size */
77#define SPDIFTX_MR_CHUNK_MASK		GENMASK(19, 16)
78
79/* Validity Bits for Channels 1 and 2 */
80#define SPDIFTX_MR_VALID1			BIT(24)
81#define SPDIFTX_MR_VALID2			BIT(25)
82
83/* Disable Null Frame on underrun */
84#define SPDIFTX_MR_DNFR_MASK		GENMASK(27, 27)
85#define SPDIFTX_MR_DNFR_INVALID		(0 << 27)
86#define SPDIFTX_MR_DNFR_VALID		(1 << 27)
87
88/* Bytes per Sample */
89#define SPDIFTX_MR_BPS_MASK		GENMASK(29, 28)
90
91/*
92 * ---- Interrupt Enable/Disable/Mask/Status Register (Write/Read-only) ----
93 */
94#define SPDIFTX_IR_TXRDY		BIT(0)
95#define SPDIFTX_IR_TXEMPTY		BIT(1)
96#define SPDIFTX_IR_TXFULL		BIT(2)
97#define SPDIFTX_IR_TXCHUNK		BIT(3)
98#define SPDIFTX_IR_TXUDR		BIT(4)
99#define SPDIFTX_IR_TXOVR		BIT(5)
100#define SPDIFTX_IR_CSRDY		BIT(6)
101#define SPDIFTX_IR_UDRDY		BIT(7)
102#define SPDIFTX_IR_TXRDYCH(ch)		BIT((ch) + 8)
103#define SPDIFTX_IR_SECE			BIT(10)
104#define SPDIFTX_IR_TXUDRCH(ch)		BIT((ch) + 11)
105#define SPDIFTX_IR_BEND			BIT(13)
106
107static bool mchp_spdiftx_readable_reg(struct device *dev, unsigned int reg)
108{
109	switch (reg) {
110	case SPDIFTX_MR:
111	case SPDIFTX_IMR:
112	case SPDIFTX_ISR:
113	case SPDIFTX_CH1UD(0):
114	case SPDIFTX_CH1UD(1):
115	case SPDIFTX_CH1UD(2):
116	case SPDIFTX_CH1UD(3):
117	case SPDIFTX_CH1UD(4):
118	case SPDIFTX_CH1UD(5):
119	case SPDIFTX_CH1S(0):
120	case SPDIFTX_CH1S(1):
121	case SPDIFTX_CH1S(2):
122	case SPDIFTX_CH1S(3):
123	case SPDIFTX_CH1S(4):
124	case SPDIFTX_CH1S(5):
125		return true;
126	default:
127		return false;
128	}
129}
130
131static bool mchp_spdiftx_writeable_reg(struct device *dev, unsigned int reg)
132{
133	switch (reg) {
134	case SPDIFTX_CR:
135	case SPDIFTX_MR:
136	case SPDIFTX_CDR:
137	case SPDIFTX_IER:
138	case SPDIFTX_IDR:
139	case SPDIFTX_CH1UD(0):
140	case SPDIFTX_CH1UD(1):
141	case SPDIFTX_CH1UD(2):
142	case SPDIFTX_CH1UD(3):
143	case SPDIFTX_CH1UD(4):
144	case SPDIFTX_CH1UD(5):
145	case SPDIFTX_CH1S(0):
146	case SPDIFTX_CH1S(1):
147	case SPDIFTX_CH1S(2):
148	case SPDIFTX_CH1S(3):
149	case SPDIFTX_CH1S(4):
150	case SPDIFTX_CH1S(5):
151		return true;
152	default:
153		return false;
154	}
155}
156
157static bool mchp_spdiftx_precious_reg(struct device *dev, unsigned int reg)
158{
159	switch (reg) {
160	case SPDIFTX_CDR:
161	case SPDIFTX_ISR:
162		return true;
163	default:
164		return false;
165	}
166}
167
168static const struct regmap_config mchp_spdiftx_regmap_config = {
169	.reg_bits = 32,
170	.reg_stride = 4,
171	.val_bits = 32,
172	.max_register = SPDIFTX_VERSION,
173	.readable_reg = mchp_spdiftx_readable_reg,
174	.writeable_reg = mchp_spdiftx_writeable_reg,
175	.precious_reg = mchp_spdiftx_precious_reg,
176	.cache_type = REGCACHE_FLAT,
177};
178
179#define SPDIFTX_GCLK_RATIO	128
180
181#define SPDIFTX_CS_BITS		192
182#define SPDIFTX_UD_BITS		192
183
184struct mchp_spdiftx_mixer_control {
185	unsigned char				ch_stat[SPDIFTX_CS_BITS / 8];
186	unsigned char				user_data[SPDIFTX_UD_BITS / 8];
187	spinlock_t				lock; /* exclusive access to control data */
188};
189
190struct mchp_spdiftx_dev {
191	struct mchp_spdiftx_mixer_control	control;
192	struct snd_dmaengine_dai_dma_data	playback;
193	struct device				*dev;
194	struct regmap				*regmap;
195	struct clk				*pclk;
196	struct clk				*gclk;
197	unsigned int				fmt;
198	unsigned int				suspend_irq;
199};
200
201static inline int mchp_spdiftx_is_running(struct mchp_spdiftx_dev *dev)
202{
203	u32 mr;
204
205	regmap_read(dev->regmap, SPDIFTX_MR, &mr);
206	return !!(mr & SPDIFTX_MR_TXEN_ENABLE);
207}
208
209static void mchp_spdiftx_channel_status_write(struct mchp_spdiftx_dev *dev)
210{
211	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
212	u32 val;
213	int i;
214
215	for (i = 0; i < ARRAY_SIZE(ctrl->ch_stat) / 4; i++) {
216		val = (ctrl->ch_stat[(i * 4) + 0] << 0) |
217		      (ctrl->ch_stat[(i * 4) + 1] << 8) |
218		      (ctrl->ch_stat[(i * 4) + 2] << 16) |
219		      (ctrl->ch_stat[(i * 4) + 3] << 24);
220
221		regmap_write(dev->regmap, SPDIFTX_CH1S(i), val);
222	}
223}
224
225static void mchp_spdiftx_user_data_write(struct mchp_spdiftx_dev *dev)
226{
227	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
228	u32 val;
229	int i;
230
231	for (i = 0; i < ARRAY_SIZE(ctrl->user_data) / 4; i++) {
232		val = (ctrl->user_data[(i * 4) + 0] << 0) |
233		      (ctrl->user_data[(i * 4) + 1] << 8) |
234		      (ctrl->user_data[(i * 4) + 2] << 16) |
235		      (ctrl->user_data[(i * 4) + 3] << 24);
236
237		regmap_write(dev->regmap, SPDIFTX_CH1UD(i), val);
238	}
239}
240
241static irqreturn_t mchp_spdiftx_interrupt(int irq, void *dev_id)
242{
243	struct mchp_spdiftx_dev *dev = dev_id;
244	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
245	u32 sr, imr, pending, idr = 0;
246
247	regmap_read(dev->regmap, SPDIFTX_ISR, &sr);
248	regmap_read(dev->regmap, SPDIFTX_IMR, &imr);
249	pending = sr & imr;
250
251	if (!pending)
252		return IRQ_NONE;
253
254	if (pending & SPDIFTX_IR_TXUDR) {
255		dev_warn(dev->dev, "underflow detected\n");
256		idr |= SPDIFTX_IR_TXUDR;
257	}
258
259	if (pending & SPDIFTX_IR_TXOVR) {
260		dev_warn(dev->dev, "overflow detected\n");
261		idr |= SPDIFTX_IR_TXOVR;
262	}
263
264	if (pending & SPDIFTX_IR_UDRDY) {
265		spin_lock(&ctrl->lock);
266		mchp_spdiftx_user_data_write(dev);
267		spin_unlock(&ctrl->lock);
268		idr |= SPDIFTX_IR_UDRDY;
269	}
270
271	if (pending & SPDIFTX_IR_CSRDY) {
272		spin_lock(&ctrl->lock);
273		mchp_spdiftx_channel_status_write(dev);
274		spin_unlock(&ctrl->lock);
275		idr |= SPDIFTX_IR_CSRDY;
276	}
277
278	regmap_write(dev->regmap, SPDIFTX_IDR, idr);
279
280	return IRQ_HANDLED;
281}
282
283static int mchp_spdiftx_dai_startup(struct snd_pcm_substream *substream,
284				    struct snd_soc_dai *dai)
285{
286	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
287
288	/* Software reset the IP */
289	regmap_write(dev->regmap, SPDIFTX_CR,
290		     SPDIFTX_CR_SWRST | SPDIFTX_CR_FCLR);
291
292	return 0;
293}
294
295static void mchp_spdiftx_dai_shutdown(struct snd_pcm_substream *substream,
296				      struct snd_soc_dai *dai)
297{
298	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
299
300	/* Disable interrupts */
301	regmap_write(dev->regmap, SPDIFTX_IDR, 0xffffffff);
302}
303
304static int mchp_spdiftx_trigger(struct snd_pcm_substream *substream, int cmd,
305				struct snd_soc_dai *dai)
306{
307	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
308	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
309	int ret;
310
311	/* do not start/stop while channel status or user data is updated */
312	spin_lock(&ctrl->lock);
313	switch (cmd) {
314	case SNDRV_PCM_TRIGGER_RESUME:
315	case SNDRV_PCM_TRIGGER_START:
316		regmap_write(dev->regmap, SPDIFTX_IER, dev->suspend_irq |
317			     SPDIFTX_IR_TXUDR | SPDIFTX_IR_TXOVR);
318		dev->suspend_irq = 0;
319		fallthrough;
320	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
321		ret = regmap_update_bits(dev->regmap, SPDIFTX_MR, SPDIFTX_MR_TXEN_MASK,
322					 SPDIFTX_MR_TXEN_ENABLE);
323		break;
324	case SNDRV_PCM_TRIGGER_SUSPEND:
325		regmap_read(dev->regmap, SPDIFTX_IMR, &dev->suspend_irq);
326		fallthrough;
327	case SNDRV_PCM_TRIGGER_STOP:
328		regmap_write(dev->regmap, SPDIFTX_IDR, dev->suspend_irq |
329			     SPDIFTX_IR_TXUDR | SPDIFTX_IR_TXOVR);
330		fallthrough;
331	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
332		ret = regmap_update_bits(dev->regmap, SPDIFTX_MR, SPDIFTX_MR_TXEN_MASK,
333					 SPDIFTX_MR_TXEN_DISABLE);
334		break;
335	default:
336		ret = -EINVAL;
337	}
338	spin_unlock(&ctrl->lock);
339	if (ret)
340		dev_err(dev->dev, "unable to start/stop TX: %d\n", ret);
341
342	return ret;
343}
344
345static int mchp_spdiftx_hw_params(struct snd_pcm_substream *substream,
346				  struct snd_pcm_hw_params *params,
347				  struct snd_soc_dai *dai)
348{
349	unsigned long flags;
350	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
351	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
352	u32 mr;
353	unsigned int bps = params_physical_width(params) / 8;
354	unsigned char aes3;
355	int ret;
356
357	dev_dbg(dev->dev, "%s() rate=%u format=%#x width=%u channels=%u\n",
358		__func__, params_rate(params), params_format(params),
359		params_width(params), params_channels(params));
360
361	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
362		dev_err(dev->dev, "Capture is not supported\n");
363		return -EINVAL;
364	}
365
366	regmap_read(dev->regmap, SPDIFTX_MR, &mr);
367
368	if (mr & SPDIFTX_MR_TXEN_ENABLE) {
369		dev_err(dev->dev, "PCM already running\n");
370		return -EBUSY;
371	}
372
373	/* Defaults: Toggle mode, justify to LSB, chunksize 1 */
374	mr = SPDIFTX_MR_CMODE_TOGGLE_ACCESS | SPDIFTX_MR_JUSTIFY_LSB;
375	dev->playback.maxburst = 1;
376	switch (params_channels(params)) {
377	case 1:
378		mr |= SPDIFTX_MR_MULTICH_MONO;
379		break;
380	case 2:
381		mr |= SPDIFTX_MR_MULTICH_DUAL;
382		if (bps > 2)
383			dev->playback.maxburst = 2;
384		break;
385	default:
386		dev_err(dev->dev, "unsupported number of channels: %d\n",
387			params_channels(params));
388		return -EINVAL;
389	}
390	mr |= FIELD_PREP(SPDIFTX_MR_CHUNK_MASK, dev->playback.maxburst);
391
392	switch (params_format(params)) {
393	case SNDRV_PCM_FORMAT_S8:
394		mr |= FIELD_PREP(SPDIFTX_MR_VBPS_MASK, 8);
395		break;
396	case SNDRV_PCM_FORMAT_S16_BE:
397		mr |= SPDIFTX_MR_ENDIAN_BIG;
398		fallthrough;
399	case SNDRV_PCM_FORMAT_S16_LE:
400		mr |= FIELD_PREP(SPDIFTX_MR_VBPS_MASK, 16);
401		break;
402	case SNDRV_PCM_FORMAT_S18_3BE:
403		mr |= SPDIFTX_MR_ENDIAN_BIG;
404		fallthrough;
405	case SNDRV_PCM_FORMAT_S18_3LE:
406		mr |= FIELD_PREP(SPDIFTX_MR_VBPS_MASK, 18);
407		break;
408	case SNDRV_PCM_FORMAT_S20_3BE:
409		mr |= SPDIFTX_MR_ENDIAN_BIG;
410		fallthrough;
411	case SNDRV_PCM_FORMAT_S20_3LE:
412		mr |= FIELD_PREP(SPDIFTX_MR_VBPS_MASK, 20);
413		break;
414	case SNDRV_PCM_FORMAT_S24_3BE:
415		mr |= SPDIFTX_MR_ENDIAN_BIG;
416		fallthrough;
417	case SNDRV_PCM_FORMAT_S24_3LE:
418		mr |= FIELD_PREP(SPDIFTX_MR_VBPS_MASK, 24);
419		break;
420	case SNDRV_PCM_FORMAT_S24_BE:
421		mr |= SPDIFTX_MR_ENDIAN_BIG;
422		fallthrough;
423	case SNDRV_PCM_FORMAT_S24_LE:
424		mr |= FIELD_PREP(SPDIFTX_MR_VBPS_MASK, 24);
425		break;
426	case SNDRV_PCM_FORMAT_S32_BE:
427		mr |= SPDIFTX_MR_ENDIAN_BIG;
428		fallthrough;
429	case SNDRV_PCM_FORMAT_S32_LE:
430		mr |= FIELD_PREP(SPDIFTX_MR_VBPS_MASK, 32);
431		break;
432	default:
433		dev_err(dev->dev, "unsupported PCM format: %d\n",
434			params_format(params));
435		return -EINVAL;
436	}
437
438	mr |= FIELD_PREP(SPDIFTX_MR_BPS_MASK, bps - 1);
439
440	switch (params_rate(params)) {
441	case 22050:
442		aes3 = IEC958_AES3_CON_FS_22050;
443		break;
444	case 24000:
445		aes3 = IEC958_AES3_CON_FS_24000;
446		break;
447	case 32000:
448		aes3 = IEC958_AES3_CON_FS_32000;
449		break;
450	case 44100:
451		aes3 = IEC958_AES3_CON_FS_44100;
452		break;
453	case 48000:
454		aes3 = IEC958_AES3_CON_FS_48000;
455		break;
456	case 88200:
457		aes3 = IEC958_AES3_CON_FS_88200;
458		break;
459	case 96000:
460		aes3 = IEC958_AES3_CON_FS_96000;
461		break;
462	case 176400:
463		aes3 = IEC958_AES3_CON_FS_176400;
464		break;
465	case 192000:
466		aes3 = IEC958_AES3_CON_FS_192000;
467		break;
468	case 8000:
469	case 11025:
470	case 16000:
471	case 64000:
472		aes3 = IEC958_AES3_CON_FS_NOTID;
473		break;
474	default:
475		dev_err(dev->dev, "unsupported sample frequency: %u\n",
476			params_rate(params));
477		return -EINVAL;
478	}
479	spin_lock_irqsave(&ctrl->lock, flags);
480	ctrl->ch_stat[3] &= ~IEC958_AES3_CON_FS;
481	ctrl->ch_stat[3] |= aes3;
482	mchp_spdiftx_channel_status_write(dev);
483	spin_unlock_irqrestore(&ctrl->lock, flags);
484
485	/* GCLK is enabled by runtime PM. */
486	clk_disable_unprepare(dev->gclk);
487
488	ret = clk_set_rate(dev->gclk, params_rate(params) *
489				      SPDIFTX_GCLK_RATIO);
490	if (ret) {
491		dev_err(dev->dev,
492			"unable to change gclk rate to: rate %u * ratio %u\n",
493			params_rate(params), SPDIFTX_GCLK_RATIO);
494		return ret;
495	}
496	ret = clk_prepare_enable(dev->gclk);
497	if (ret) {
498		dev_err(dev->dev, "unable to enable gclk: %d\n", ret);
499		return ret;
500	}
501
502	dev_dbg(dev->dev, "%s(): GCLK set to %d\n", __func__,
503		params_rate(params) * SPDIFTX_GCLK_RATIO);
504
505	regmap_write(dev->regmap, SPDIFTX_MR, mr);
506
507	return 0;
508}
509
510static int mchp_spdiftx_hw_free(struct snd_pcm_substream *substream,
511				struct snd_soc_dai *dai)
512{
513	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
514
515	return regmap_write(dev->regmap, SPDIFTX_CR,
516			    SPDIFTX_CR_SWRST | SPDIFTX_CR_FCLR);
517}
518
519#define MCHP_SPDIFTX_RATES	SNDRV_PCM_RATE_8000_192000
520
521#define MCHP_SPDIFTX_FORMATS	(SNDRV_PCM_FMTBIT_S8 |		\
522				 SNDRV_PCM_FMTBIT_S16_LE |	\
523				 SNDRV_PCM_FMTBIT_U16_BE |	\
524				 SNDRV_PCM_FMTBIT_S18_3LE |	\
525				 SNDRV_PCM_FMTBIT_S18_3BE |	\
526				 SNDRV_PCM_FMTBIT_S20_3LE |	\
527				 SNDRV_PCM_FMTBIT_S20_3BE |	\
528				 SNDRV_PCM_FMTBIT_S24_3LE |	\
529				 SNDRV_PCM_FMTBIT_S24_3BE |	\
530				 SNDRV_PCM_FMTBIT_S24_LE |	\
531				 SNDRV_PCM_FMTBIT_S24_BE |	\
532				 SNDRV_PCM_FMTBIT_S32_LE |	\
533				 SNDRV_PCM_FMTBIT_S32_BE	\
534				 )
535
536static int mchp_spdiftx_info(struct snd_kcontrol *kcontrol,
537			     struct snd_ctl_elem_info *uinfo)
538{
539	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
540	uinfo->count = 1;
541
542	return 0;
543}
544
545static int mchp_spdiftx_cs_get(struct snd_kcontrol *kcontrol,
546			       struct snd_ctl_elem_value *uvalue)
547{
548	unsigned long flags;
549	struct snd_soc_dai *dai = snd_kcontrol_chip(kcontrol);
550	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
551	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
552
553	spin_lock_irqsave(&ctrl->lock, flags);
554	memcpy(uvalue->value.iec958.status, ctrl->ch_stat,
555	       sizeof(ctrl->ch_stat));
556	spin_unlock_irqrestore(&ctrl->lock, flags);
557
558	return 0;
559}
560
561static int mchp_spdiftx_cs_put(struct snd_kcontrol *kcontrol,
562			       struct snd_ctl_elem_value *uvalue)
563{
564	unsigned long flags;
565	struct snd_soc_dai *dai = snd_kcontrol_chip(kcontrol);
566	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
567	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
568	int changed = 0;
569	int i;
570
571	spin_lock_irqsave(&ctrl->lock, flags);
572	for (i = 0; i < ARRAY_SIZE(ctrl->ch_stat); i++) {
573		if (ctrl->ch_stat[i] != uvalue->value.iec958.status[i])
574			changed = 1;
575		ctrl->ch_stat[i] = uvalue->value.iec958.status[i];
576	}
577
578	if (changed) {
579		/* don't enable IP while we copy the channel status */
580		if (mchp_spdiftx_is_running(dev)) {
581			/*
582			 * if SPDIF is running, wait for interrupt to write
583			 * channel status
584			 */
585			regmap_write(dev->regmap, SPDIFTX_IER,
586				     SPDIFTX_IR_CSRDY);
587		} else {
588			mchp_spdiftx_channel_status_write(dev);
589		}
590	}
591	spin_unlock_irqrestore(&ctrl->lock, flags);
592
593	return changed;
594}
595
596static int mchp_spdiftx_cs_mask(struct snd_kcontrol *kcontrol,
597				struct snd_ctl_elem_value *uvalue)
598{
599	memset(uvalue->value.iec958.status, 0xff,
600	       sizeof(uvalue->value.iec958.status));
601
602	return 0;
603}
604
605static int mchp_spdiftx_subcode_get(struct snd_kcontrol *kcontrol,
606				    struct snd_ctl_elem_value *uvalue)
607{
608	struct snd_soc_dai *dai = snd_kcontrol_chip(kcontrol);
609	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
610	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
611	unsigned long flags;
612
613	spin_lock_irqsave(&ctrl->lock, flags);
614	memcpy(uvalue->value.iec958.subcode, ctrl->user_data,
615	       sizeof(ctrl->user_data));
616	spin_unlock_irqrestore(&ctrl->lock, flags);
617
618	return 0;
619}
620
621static int mchp_spdiftx_subcode_put(struct snd_kcontrol *kcontrol,
622				    struct snd_ctl_elem_value *uvalue)
623{
624	unsigned long flags;
625	struct snd_soc_dai *dai = snd_kcontrol_chip(kcontrol);
626	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
627	struct mchp_spdiftx_mixer_control *ctrl = &dev->control;
628	int changed = 0;
629	int i;
630
631	spin_lock_irqsave(&ctrl->lock, flags);
632	for (i = 0; i < ARRAY_SIZE(ctrl->user_data); i++) {
633		if (ctrl->user_data[i] != uvalue->value.iec958.subcode[i])
634			changed = 1;
635
636		ctrl->user_data[i] = uvalue->value.iec958.subcode[i];
637	}
638	if (changed) {
639		if (mchp_spdiftx_is_running(dev)) {
640			/*
641			 * if SPDIF is running, wait for interrupt to write
642			 * user data
643			 */
644			regmap_write(dev->regmap, SPDIFTX_IER,
645				     SPDIFTX_IR_UDRDY);
646		} else {
647			mchp_spdiftx_user_data_write(dev);
648		}
649	}
650	spin_unlock_irqrestore(&ctrl->lock, flags);
651
652	return changed;
653}
654
655static struct snd_kcontrol_new mchp_spdiftx_ctrls[] = {
656	/* Channel status controller */
657	{
658		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
659		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
660		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
661			SNDRV_CTL_ELEM_ACCESS_VOLATILE,
662		.info = mchp_spdiftx_info,
663		.get = mchp_spdiftx_cs_get,
664		.put = mchp_spdiftx_cs_put,
665	},
666	{
667		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
668		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
669		.access = SNDRV_CTL_ELEM_ACCESS_READ,
670			SNDRV_CTL_ELEM_ACCESS_VOLATILE,
671		.info = mchp_spdiftx_info,
672		.get = mchp_spdiftx_cs_mask,
673	},
674	/* User bits controller */
675	{
676		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
677		.name = "IEC958 Subcode Playback Default",
678		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
679		.info = mchp_spdiftx_info,
680		.get = mchp_spdiftx_subcode_get,
681		.put = mchp_spdiftx_subcode_put,
682	},
683};
684
685static int mchp_spdiftx_dai_probe(struct snd_soc_dai *dai)
686{
687	struct mchp_spdiftx_dev *dev = snd_soc_dai_get_drvdata(dai);
688
689	snd_soc_dai_init_dma_data(dai, &dev->playback, NULL);
690
691	/* Add controls */
692	snd_soc_add_dai_controls(dai, mchp_spdiftx_ctrls,
693				 ARRAY_SIZE(mchp_spdiftx_ctrls));
694
695	return 0;
696}
697
698static const struct snd_soc_dai_ops mchp_spdiftx_dai_ops = {
699	.probe		= mchp_spdiftx_dai_probe,
700	.startup	= mchp_spdiftx_dai_startup,
701	.shutdown	= mchp_spdiftx_dai_shutdown,
702	.trigger	= mchp_spdiftx_trigger,
703	.hw_params	= mchp_spdiftx_hw_params,
704	.hw_free	= mchp_spdiftx_hw_free,
705};
706
707static struct snd_soc_dai_driver mchp_spdiftx_dai = {
708	.name = "mchp-spdiftx",
709	.playback = {
710		.stream_name = "S/PDIF Playback",
711		.channels_min = 1,
712		.channels_max = 2,
713		.rates = MCHP_SPDIFTX_RATES,
714		.formats = MCHP_SPDIFTX_FORMATS,
715	},
716	.ops = &mchp_spdiftx_dai_ops,
717};
718
719static const struct snd_soc_component_driver mchp_spdiftx_component = {
720	.name			= "mchp-spdiftx",
721	.legacy_dai_naming	= 1,
722};
723
724static const struct of_device_id mchp_spdiftx_dt_ids[] = {
725	{
726		.compatible = "microchip,sama7g5-spdiftx",
727	},
728	{ /* sentinel */ }
729};
730MODULE_DEVICE_TABLE(of, mchp_spdiftx_dt_ids);
731
732static int mchp_spdiftx_runtime_suspend(struct device *dev)
733{
734	struct mchp_spdiftx_dev *spdiftx = dev_get_drvdata(dev);
735
736	regcache_cache_only(spdiftx->regmap, true);
737
738	clk_disable_unprepare(spdiftx->gclk);
739	clk_disable_unprepare(spdiftx->pclk);
740
741	return 0;
742}
743
744static int mchp_spdiftx_runtime_resume(struct device *dev)
745{
746	struct mchp_spdiftx_dev *spdiftx = dev_get_drvdata(dev);
747	int ret;
748
749	ret = clk_prepare_enable(spdiftx->pclk);
750	if (ret) {
751		dev_err(spdiftx->dev,
752			"failed to enable the peripheral clock: %d\n", ret);
753		return ret;
754	}
755	ret = clk_prepare_enable(spdiftx->gclk);
756	if (ret) {
757		dev_err(spdiftx->dev,
758			"failed to enable generic clock: %d\n", ret);
759		goto disable_pclk;
760	}
761
762	regcache_cache_only(spdiftx->regmap, false);
763	regcache_mark_dirty(spdiftx->regmap);
764	ret = regcache_sync(spdiftx->regmap);
765	if (ret) {
766		regcache_cache_only(spdiftx->regmap, true);
767		clk_disable_unprepare(spdiftx->gclk);
768disable_pclk:
769		clk_disable_unprepare(spdiftx->pclk);
770	}
771
772	return ret;
773}
774
775static const struct dev_pm_ops mchp_spdiftx_pm_ops = {
776	SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
777	RUNTIME_PM_OPS(mchp_spdiftx_runtime_suspend, mchp_spdiftx_runtime_resume,
778		       NULL)
779};
780
781static int mchp_spdiftx_probe(struct platform_device *pdev)
782{
783	struct mchp_spdiftx_dev *dev;
784	struct resource *mem;
785	struct regmap *regmap;
786	void __iomem *base;
787	struct mchp_spdiftx_mixer_control *ctrl;
788	int irq;
789	int err;
790
791	/* Get memory for driver data. */
792	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
793	if (!dev)
794		return -ENOMEM;
795
796	/* Map I/O registers. */
797	base = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
798	if (IS_ERR(base))
799		return PTR_ERR(base);
800
801	regmap = devm_regmap_init_mmio(&pdev->dev, base,
802				       &mchp_spdiftx_regmap_config);
803	if (IS_ERR(regmap))
804		return PTR_ERR(regmap);
805
806	/* Request IRQ */
807	irq = platform_get_irq(pdev, 0);
808	if (irq < 0)
809		return irq;
810
811	err = devm_request_irq(&pdev->dev, irq, mchp_spdiftx_interrupt, 0,
812			       dev_name(&pdev->dev), dev);
813	if (err)
814		return err;
815
816	/* Get the peripheral clock */
817	dev->pclk = devm_clk_get(&pdev->dev, "pclk");
818	if (IS_ERR(dev->pclk)) {
819		err = PTR_ERR(dev->pclk);
820		dev_err(&pdev->dev,
821			"failed to get the peripheral clock: %d\n", err);
822		return err;
823	}
824
825	/* Get the generic clock */
826	dev->gclk = devm_clk_get(&pdev->dev, "gclk");
827	if (IS_ERR(dev->gclk)) {
828		err = PTR_ERR(dev->gclk);
829		dev_err(&pdev->dev,
830			"failed to get the PMC generic clock: %d\n", err);
831		return err;
832	}
833
834	ctrl = &dev->control;
835	spin_lock_init(&ctrl->lock);
836
837	/* Init channel status */
838	ctrl->ch_stat[0] = IEC958_AES0_CON_NOT_COPYRIGHT |
839			   IEC958_AES0_CON_EMPHASIS_NONE;
840
841	dev->dev = &pdev->dev;
842	dev->regmap = regmap;
843	platform_set_drvdata(pdev, dev);
844
845	pm_runtime_enable(dev->dev);
846	if (!pm_runtime_enabled(dev->dev)) {
847		err = mchp_spdiftx_runtime_resume(dev->dev);
848		if (err)
849			return err;
850	}
851
852	dev->playback.addr = (dma_addr_t)mem->start + SPDIFTX_CDR;
853	dev->playback.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
854
855	err = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
856	if (err) {
857		dev_err(&pdev->dev, "failed to register PMC: %d\n", err);
858		goto pm_runtime_suspend;
859	}
860
861	err = devm_snd_soc_register_component(&pdev->dev,
862					      &mchp_spdiftx_component,
863					      &mchp_spdiftx_dai, 1);
864	if (err) {
865		dev_err(&pdev->dev, "failed to register component: %d\n", err);
866		goto pm_runtime_suspend;
867	}
868
869	return 0;
870
871pm_runtime_suspend:
872	if (!pm_runtime_status_suspended(dev->dev))
873		mchp_spdiftx_runtime_suspend(dev->dev);
874	pm_runtime_disable(dev->dev);
875
876	return err;
877}
878
879static void mchp_spdiftx_remove(struct platform_device *pdev)
880{
881	struct mchp_spdiftx_dev *dev = platform_get_drvdata(pdev);
882
883	if (!pm_runtime_status_suspended(dev->dev))
884		mchp_spdiftx_runtime_suspend(dev->dev);
885
886	pm_runtime_disable(dev->dev);
887}
888
889static struct platform_driver mchp_spdiftx_driver = {
890	.probe	= mchp_spdiftx_probe,
891	.remove_new = mchp_spdiftx_remove,
892	.driver	= {
893		.name	= "mchp_spdiftx",
894		.of_match_table = mchp_spdiftx_dt_ids,
895		.pm = pm_ptr(&mchp_spdiftx_pm_ops)
896	},
897};
898
899module_platform_driver(mchp_spdiftx_driver);
900
901MODULE_AUTHOR("Codrin Ciubotariu <codrin.ciubotariu@microchip.com>");
902MODULE_DESCRIPTION("Microchip S/PDIF TX Controller Driver");
903MODULE_LICENSE("GPL v2");
904