xref: /linux/sound/soc/atmel/mchp-spdiftx.c (revision db10cb9b)
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 
107 static 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 
131 static 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 
157 static 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 
168 static 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 
184 struct 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 
190 struct 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 
201 static 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 
209 static 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 
225 static 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 
241 static 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 
283 static 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 
295 static 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 
304 static 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 
345 static 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 
510 static 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 
536 static 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 
545 static 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 
561 static 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 
596 static 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 
605 static 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 
621 static 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 
655 static 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 
685 static 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 
698 static 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 
707 static 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 
719 static const struct snd_soc_component_driver mchp_spdiftx_component = {
720 	.name			= "mchp-spdiftx",
721 	.legacy_dai_naming	= 1,
722 };
723 
724 static const struct of_device_id mchp_spdiftx_dt_ids[] = {
725 	{
726 		.compatible = "microchip,sama7g5-spdiftx",
727 	},
728 	{ /* sentinel */ }
729 };
730 MODULE_DEVICE_TABLE(of, mchp_spdiftx_dt_ids);
731 
732 static 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 
744 static 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);
768 disable_pclk:
769 		clk_disable_unprepare(spdiftx->pclk);
770 	}
771 
772 	return ret;
773 }
774 
775 static 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 
781 static 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 
871 pm_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 
879 static 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 
889 static 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 
899 module_platform_driver(mchp_spdiftx_driver);
900 
901 MODULE_AUTHOR("Codrin Ciubotariu <codrin.ciubotariu@microchip.com>");
902 MODULE_DESCRIPTION("Microchip S/PDIF TX Controller Driver");
903 MODULE_LICENSE("GPL v2");
904