1/*
2 * Xtfpga I2S controller driver
3 *
4 * Copyright (c) 2014 Cadence Design Systems Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/clk.h>
12#include <linux/io.h>
13#include <linux/module.h>
14#include <linux/of.h>
15#include <linux/platform_device.h>
16#include <linux/pm_runtime.h>
17#include <sound/pcm_params.h>
18#include <sound/soc.h>
19
20#define DRV_NAME	"xtfpga-i2s"
21
22#define XTFPGA_I2S_VERSION	0x00
23#define XTFPGA_I2S_CONFIG	0x04
24#define XTFPGA_I2S_INT_MASK	0x08
25#define XTFPGA_I2S_INT_STATUS	0x0c
26#define XTFPGA_I2S_CHAN0_DATA	0x10
27#define XTFPGA_I2S_CHAN1_DATA	0x14
28#define XTFPGA_I2S_CHAN2_DATA	0x18
29#define XTFPGA_I2S_CHAN3_DATA	0x1c
30
31#define XTFPGA_I2S_CONFIG_TX_ENABLE	0x1
32#define XTFPGA_I2S_CONFIG_INT_ENABLE	0x2
33#define XTFPGA_I2S_CONFIG_LEFT		0x4
34#define XTFPGA_I2S_CONFIG_RATIO_BASE	8
35#define XTFPGA_I2S_CONFIG_RATIO_MASK	0x0000ff00
36#define XTFPGA_I2S_CONFIG_RES_BASE	16
37#define XTFPGA_I2S_CONFIG_RES_MASK	0x003f0000
38#define XTFPGA_I2S_CONFIG_LEVEL_BASE	24
39#define XTFPGA_I2S_CONFIG_LEVEL_MASK	0x0f000000
40#define XTFPGA_I2S_CONFIG_CHANNEL_BASE	28
41
42#define XTFPGA_I2S_INT_UNDERRUN		0x1
43#define XTFPGA_I2S_INT_LEVEL		0x2
44#define XTFPGA_I2S_INT_VALID		0x3
45
46#define XTFPGA_I2S_FIFO_SIZE		8192
47
48/*
49 * I2S controller operation:
50 *
51 * Enabling TX: output 1 period of zeros (starting with left channel)
52 * and then queued data.
53 *
54 * Level status and interrupt: whenever FIFO level is below FIFO trigger,
55 * level status is 1 and an IRQ is asserted (if enabled).
56 *
57 * Underrun status and interrupt: whenever FIFO is empty, underrun status
58 * is 1 and an IRQ is asserted (if enabled).
59 */
60struct xtfpga_i2s {
61	struct device *dev;
62	struct clk *clk;
63	struct regmap *regmap;
64	void __iomem *regs;
65
66	/* current playback substream. NULL if not playing.
67	 *
68	 * Access to that field is synchronized between the interrupt handler
69	 * and userspace through RCU.
70	 *
71	 * Interrupt handler (threaded part) does PIO on substream data in RCU
72	 * read-side critical section. Trigger callback sets and clears the
73	 * pointer when the playback is started and stopped with
74	 * rcu_assign_pointer. When userspace is about to free the playback
75	 * stream in the pcm_close callback it synchronizes with the interrupt
76	 * handler by means of synchronize_rcu call.
77	 */
78	struct snd_pcm_substream *tx_substream;
79	unsigned (*tx_fn)(struct xtfpga_i2s *i2s,
80			  struct snd_pcm_runtime *runtime,
81			  unsigned tx_ptr);
82	unsigned tx_ptr; /* next frame index in the sample buffer */
83
84	/* current fifo level estimate.
85	 * Doesn't have to be perfectly accurate, but must be not less than
86	 * the actual FIFO level in order to avoid stall on push attempt.
87	 */
88	unsigned tx_fifo_level;
89
90	/* FIFO level at which level interrupt occurs */
91	unsigned tx_fifo_low;
92
93	/* maximal FIFO level */
94	unsigned tx_fifo_high;
95};
96
97static bool xtfpga_i2s_wr_reg(struct device *dev, unsigned int reg)
98{
99	return reg >= XTFPGA_I2S_CONFIG;
100}
101
102static bool xtfpga_i2s_rd_reg(struct device *dev, unsigned int reg)
103{
104	return reg < XTFPGA_I2S_CHAN0_DATA;
105}
106
107static bool xtfpga_i2s_volatile_reg(struct device *dev, unsigned int reg)
108{
109	return reg == XTFPGA_I2S_INT_STATUS;
110}
111
112static const struct regmap_config xtfpga_i2s_regmap_config = {
113	.reg_bits = 32,
114	.reg_stride = 4,
115	.val_bits = 32,
116	.max_register = XTFPGA_I2S_CHAN3_DATA,
117	.writeable_reg = xtfpga_i2s_wr_reg,
118	.readable_reg = xtfpga_i2s_rd_reg,
119	.volatile_reg = xtfpga_i2s_volatile_reg,
120	.cache_type = REGCACHE_FLAT,
121};
122
123/* Generate functions that do PIO from TX DMA area to FIFO for all supported
124 * stream formats.
125 * Functions will be called xtfpga_pcm_tx_<channels>x<sample bits>, e.g.
126 * xtfpga_pcm_tx_2x16 for 16-bit stereo.
127 *
128 * FIFO consists of 32-bit words, one word per channel, always 2 channels.
129 * If I2S interface is configured with smaller sample resolution, only
130 * the LSB of each word is used.
131 */
132#define xtfpga_pcm_tx_fn(channels, sample_bits) \
133static unsigned xtfpga_pcm_tx_##channels##x##sample_bits( \
134	struct xtfpga_i2s *i2s, struct snd_pcm_runtime *runtime, \
135	unsigned tx_ptr) \
136{ \
137	const u##sample_bits (*p)[channels] = \
138		(void *)runtime->dma_area; \
139\
140	for (; i2s->tx_fifo_level < i2s->tx_fifo_high; \
141	     i2s->tx_fifo_level += 2) { \
142		iowrite32(p[tx_ptr][0], \
143			  i2s->regs + XTFPGA_I2S_CHAN0_DATA); \
144		iowrite32(p[tx_ptr][channels - 1], \
145			  i2s->regs + XTFPGA_I2S_CHAN0_DATA); \
146		if (++tx_ptr >= runtime->buffer_size) \
147			tx_ptr = 0; \
148	} \
149	return tx_ptr; \
150}
151
152xtfpga_pcm_tx_fn(1, 16)
153xtfpga_pcm_tx_fn(2, 16)
154xtfpga_pcm_tx_fn(1, 32)
155xtfpga_pcm_tx_fn(2, 32)
156
157#undef xtfpga_pcm_tx_fn
158
159static bool xtfpga_pcm_push_tx(struct xtfpga_i2s *i2s)
160{
161	struct snd_pcm_substream *tx_substream;
162	bool tx_active;
163
164	rcu_read_lock();
165	tx_substream = rcu_dereference(i2s->tx_substream);
166	tx_active = tx_substream && snd_pcm_running(tx_substream);
167	if (tx_active) {
168		unsigned tx_ptr = ACCESS_ONCE(i2s->tx_ptr);
169		unsigned new_tx_ptr = i2s->tx_fn(i2s, tx_substream->runtime,
170						 tx_ptr);
171
172		cmpxchg(&i2s->tx_ptr, tx_ptr, new_tx_ptr);
173	}
174	rcu_read_unlock();
175
176	return tx_active;
177}
178
179static void xtfpga_pcm_refill_fifo(struct xtfpga_i2s *i2s)
180{
181	unsigned int_status;
182	unsigned i;
183
184	regmap_read(i2s->regmap, XTFPGA_I2S_INT_STATUS,
185		    &int_status);
186
187	for (i = 0; i < 2; ++i) {
188		bool tx_active = xtfpga_pcm_push_tx(i2s);
189
190		regmap_write(i2s->regmap, XTFPGA_I2S_INT_STATUS,
191			     XTFPGA_I2S_INT_VALID);
192		if (tx_active)
193			regmap_read(i2s->regmap, XTFPGA_I2S_INT_STATUS,
194				    &int_status);
195
196		if (!tx_active ||
197		    !(int_status & XTFPGA_I2S_INT_LEVEL))
198			break;
199
200		/* After the push the level IRQ is still asserted,
201		 * means FIFO level is below tx_fifo_low. Estimate
202		 * it as tx_fifo_low.
203		 */
204		i2s->tx_fifo_level = i2s->tx_fifo_low;
205	}
206
207	if (!(int_status & XTFPGA_I2S_INT_LEVEL))
208		regmap_write(i2s->regmap, XTFPGA_I2S_INT_MASK,
209			     XTFPGA_I2S_INT_VALID);
210	else if (!(int_status & XTFPGA_I2S_INT_UNDERRUN))
211		regmap_write(i2s->regmap, XTFPGA_I2S_INT_MASK,
212			     XTFPGA_I2S_INT_UNDERRUN);
213
214	if (!(int_status & XTFPGA_I2S_INT_UNDERRUN))
215		regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
216				   XTFPGA_I2S_CONFIG_INT_ENABLE |
217				   XTFPGA_I2S_CONFIG_TX_ENABLE,
218				   XTFPGA_I2S_CONFIG_INT_ENABLE |
219				   XTFPGA_I2S_CONFIG_TX_ENABLE);
220	else
221		regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
222				   XTFPGA_I2S_CONFIG_INT_ENABLE |
223				   XTFPGA_I2S_CONFIG_TX_ENABLE, 0);
224}
225
226static irqreturn_t xtfpga_i2s_threaded_irq_handler(int irq, void *dev_id)
227{
228	struct xtfpga_i2s *i2s = dev_id;
229	struct snd_pcm_substream *tx_substream;
230	unsigned config, int_status, int_mask;
231
232	regmap_read(i2s->regmap, XTFPGA_I2S_CONFIG, &config);
233	regmap_read(i2s->regmap, XTFPGA_I2S_INT_MASK, &int_mask);
234	regmap_read(i2s->regmap, XTFPGA_I2S_INT_STATUS, &int_status);
235
236	if (!(config & XTFPGA_I2S_CONFIG_INT_ENABLE) ||
237	    !(int_status & int_mask & XTFPGA_I2S_INT_VALID))
238		return IRQ_NONE;
239
240	/* Update FIFO level estimate in accordance with interrupt status
241	 * register.
242	 */
243	if (int_status & XTFPGA_I2S_INT_UNDERRUN) {
244		i2s->tx_fifo_level = 0;
245		regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
246				   XTFPGA_I2S_CONFIG_TX_ENABLE, 0);
247	} else {
248		/* The FIFO isn't empty, but is below tx_fifo_low. Estimate
249		 * it as tx_fifo_low.
250		 */
251		i2s->tx_fifo_level = i2s->tx_fifo_low;
252	}
253
254	rcu_read_lock();
255	tx_substream = rcu_dereference(i2s->tx_substream);
256
257	if (tx_substream && snd_pcm_running(tx_substream)) {
258		snd_pcm_period_elapsed(tx_substream);
259		if (int_status & XTFPGA_I2S_INT_UNDERRUN)
260			dev_dbg_ratelimited(i2s->dev, "%s: underrun\n",
261					    __func__);
262	}
263	rcu_read_unlock();
264
265	/* Refill FIFO, update allowed IRQ reasons, enable IRQ if FIFO is
266	 * not empty.
267	 */
268	xtfpga_pcm_refill_fifo(i2s);
269
270	return IRQ_HANDLED;
271}
272
273static int xtfpga_i2s_startup(struct snd_pcm_substream *substream,
274			      struct snd_soc_dai *dai)
275{
276	struct xtfpga_i2s *i2s = snd_soc_dai_get_drvdata(dai);
277
278	snd_soc_dai_set_dma_data(dai, substream, i2s);
279	return 0;
280}
281
282static int xtfpga_i2s_hw_params(struct snd_pcm_substream *substream,
283				struct snd_pcm_hw_params *params,
284				struct snd_soc_dai *dai)
285{
286	struct xtfpga_i2s *i2s = snd_soc_dai_get_drvdata(dai);
287	unsigned srate = params_rate(params);
288	unsigned channels = params_channels(params);
289	unsigned period_size = params_period_size(params);
290	unsigned sample_size = snd_pcm_format_width(params_format(params));
291	unsigned freq, ratio, level;
292	int err;
293
294	regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
295			   XTFPGA_I2S_CONFIG_RES_MASK,
296			   sample_size << XTFPGA_I2S_CONFIG_RES_BASE);
297
298	freq = 256 * srate;
299	err = clk_set_rate(i2s->clk, freq);
300	if (err < 0)
301		return err;
302
303	/* ratio field of the config register controls MCLK->I2S clock
304	 * derivation: I2S clock = MCLK / (2 * (ratio + 2)).
305	 *
306	 * So with MCLK = 256 * sample rate ratio is 0 for 32 bit stereo
307	 * and 2 for 16 bit stereo.
308	 */
309	ratio = (freq - (srate * sample_size * 8)) /
310		(srate * sample_size * 4);
311
312	regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
313			   XTFPGA_I2S_CONFIG_RATIO_MASK,
314			   ratio << XTFPGA_I2S_CONFIG_RATIO_BASE);
315
316	i2s->tx_fifo_low = XTFPGA_I2S_FIFO_SIZE / 2;
317
318	/* period_size * 2: FIFO always gets 2 samples per frame */
319	for (level = 1;
320	     i2s->tx_fifo_low / 2 >= period_size * 2 &&
321	     level < (XTFPGA_I2S_CONFIG_LEVEL_MASK >>
322		      XTFPGA_I2S_CONFIG_LEVEL_BASE); ++level)
323		i2s->tx_fifo_low /= 2;
324
325	i2s->tx_fifo_high = 2 * i2s->tx_fifo_low;
326
327	regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
328			   XTFPGA_I2S_CONFIG_LEVEL_MASK,
329			   level << XTFPGA_I2S_CONFIG_LEVEL_BASE);
330
331	dev_dbg(i2s->dev,
332		"%s srate: %u, channels: %u, sample_size: %u, period_size: %u\n",
333		__func__, srate, channels, sample_size, period_size);
334	dev_dbg(i2s->dev, "%s freq: %u, ratio: %u, level: %u\n",
335		__func__, freq, ratio, level);
336
337	return 0;
338}
339
340static int xtfpga_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
341			      unsigned int fmt)
342{
343	if ((fmt & SND_SOC_DAIFMT_INV_MASK) != SND_SOC_DAIFMT_NB_NF)
344		return -EINVAL;
345	if ((fmt & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBS_CFS)
346		return -EINVAL;
347	if ((fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_I2S)
348		return -EINVAL;
349
350	return 0;
351}
352
353/* PCM */
354
355static const struct snd_pcm_hardware xtfpga_pcm_hardware = {
356	.info = SNDRV_PCM_INFO_INTERLEAVED |
357		SNDRV_PCM_INFO_MMAP_VALID |
358		SNDRV_PCM_INFO_BLOCK_TRANSFER,
359	.formats		= SNDRV_PCM_FMTBIT_S16_LE |
360				  SNDRV_PCM_FMTBIT_S32_LE,
361	.channels_min		= 1,
362	.channels_max		= 2,
363	.period_bytes_min	= 2,
364	.period_bytes_max	= XTFPGA_I2S_FIFO_SIZE / 2 * 8,
365	.periods_min		= 2,
366	.periods_max		= XTFPGA_I2S_FIFO_SIZE * 8 / 2,
367	.buffer_bytes_max	= XTFPGA_I2S_FIFO_SIZE * 8,
368	.fifo_size		= 16,
369};
370
371static int xtfpga_pcm_open(struct snd_pcm_substream *substream)
372{
373	struct snd_pcm_runtime *runtime = substream->runtime;
374	struct snd_soc_pcm_runtime *rtd = substream->private_data;
375	void *p;
376
377	snd_soc_set_runtime_hwparams(substream, &xtfpga_pcm_hardware);
378	p = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
379	runtime->private_data = p;
380
381	return 0;
382}
383
384static int xtfpga_pcm_close(struct snd_pcm_substream *substream)
385{
386	synchronize_rcu();
387	return 0;
388}
389
390static int xtfpga_pcm_hw_params(struct snd_pcm_substream *substream,
391				struct snd_pcm_hw_params *hw_params)
392{
393	int ret;
394	struct snd_pcm_runtime *runtime = substream->runtime;
395	struct xtfpga_i2s *i2s = runtime->private_data;
396	unsigned channels = params_channels(hw_params);
397
398	switch (channels) {
399	case 1:
400	case 2:
401		break;
402
403	default:
404		return -EINVAL;
405
406	}
407
408	switch (params_format(hw_params)) {
409	case SNDRV_PCM_FORMAT_S16_LE:
410		i2s->tx_fn = (channels == 1) ?
411			xtfpga_pcm_tx_1x16 :
412			xtfpga_pcm_tx_2x16;
413		break;
414
415	case SNDRV_PCM_FORMAT_S32_LE:
416		i2s->tx_fn = (channels == 1) ?
417			xtfpga_pcm_tx_1x32 :
418			xtfpga_pcm_tx_2x32;
419		break;
420
421	default:
422		return -EINVAL;
423	}
424
425	ret = snd_pcm_lib_malloc_pages(substream,
426				       params_buffer_bytes(hw_params));
427	return ret;
428}
429
430static int xtfpga_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
431{
432	int ret = 0;
433	struct snd_pcm_runtime *runtime = substream->runtime;
434	struct xtfpga_i2s *i2s = runtime->private_data;
435
436	switch (cmd) {
437	case SNDRV_PCM_TRIGGER_START:
438	case SNDRV_PCM_TRIGGER_RESUME:
439	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
440		ACCESS_ONCE(i2s->tx_ptr) = 0;
441		rcu_assign_pointer(i2s->tx_substream, substream);
442		xtfpga_pcm_refill_fifo(i2s);
443		break;
444
445	case SNDRV_PCM_TRIGGER_STOP:
446	case SNDRV_PCM_TRIGGER_SUSPEND:
447	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
448		rcu_assign_pointer(i2s->tx_substream, NULL);
449		break;
450
451	default:
452		ret = -EINVAL;
453		break;
454	}
455	return ret;
456}
457
458static snd_pcm_uframes_t xtfpga_pcm_pointer(struct snd_pcm_substream *substream)
459{
460	struct snd_pcm_runtime *runtime = substream->runtime;
461	struct xtfpga_i2s *i2s = runtime->private_data;
462	snd_pcm_uframes_t pos = ACCESS_ONCE(i2s->tx_ptr);
463
464	return pos < runtime->buffer_size ? pos : 0;
465}
466
467static int xtfpga_pcm_new(struct snd_soc_pcm_runtime *rtd)
468{
469	struct snd_card *card = rtd->card->snd_card;
470	size_t size = xtfpga_pcm_hardware.buffer_bytes_max;
471
472	return snd_pcm_lib_preallocate_pages_for_all(rtd->pcm,
473						     SNDRV_DMA_TYPE_DEV,
474						     card->dev, size, size);
475}
476
477static void xtfpga_pcm_free(struct snd_pcm *pcm)
478{
479	snd_pcm_lib_preallocate_free_for_all(pcm);
480}
481
482static const struct snd_pcm_ops xtfpga_pcm_ops = {
483	.open		= xtfpga_pcm_open,
484	.close		= xtfpga_pcm_close,
485	.ioctl		= snd_pcm_lib_ioctl,
486	.hw_params	= xtfpga_pcm_hw_params,
487	.trigger	= xtfpga_pcm_trigger,
488	.pointer	= xtfpga_pcm_pointer,
489};
490
491static const struct snd_soc_platform_driver xtfpga_soc_platform = {
492	.pcm_new	= xtfpga_pcm_new,
493	.pcm_free	= xtfpga_pcm_free,
494	.ops		= &xtfpga_pcm_ops,
495};
496
497static const struct snd_soc_component_driver xtfpga_i2s_component = {
498	.name		= DRV_NAME,
499};
500
501static const struct snd_soc_dai_ops xtfpga_i2s_dai_ops = {
502	.startup	= xtfpga_i2s_startup,
503	.hw_params      = xtfpga_i2s_hw_params,
504	.set_fmt        = xtfpga_i2s_set_fmt,
505};
506
507static struct snd_soc_dai_driver xtfpga_i2s_dai[] = {
508	{
509		.name = "xtfpga-i2s",
510		.id = 0,
511		.playback = {
512			.channels_min = 1,
513			.channels_max = 2,
514			.rates = SNDRV_PCM_RATE_8000_96000,
515			.formats = SNDRV_PCM_FMTBIT_S16_LE |
516				   SNDRV_PCM_FMTBIT_S32_LE,
517		},
518		.ops = &xtfpga_i2s_dai_ops,
519	},
520};
521
522static int xtfpga_i2s_runtime_suspend(struct device *dev)
523{
524	struct xtfpga_i2s *i2s = dev_get_drvdata(dev);
525
526	clk_disable_unprepare(i2s->clk);
527	return 0;
528}
529
530static int xtfpga_i2s_runtime_resume(struct device *dev)
531{
532	struct xtfpga_i2s *i2s = dev_get_drvdata(dev);
533	int ret;
534
535	ret = clk_prepare_enable(i2s->clk);
536	if (ret) {
537		dev_err(dev, "clk_prepare_enable failed: %d\n", ret);
538		return ret;
539	}
540	return 0;
541}
542
543static int xtfpga_i2s_probe(struct platform_device *pdev)
544{
545	struct xtfpga_i2s *i2s;
546	struct resource *mem;
547	int err, irq;
548
549	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
550	if (!i2s) {
551		err = -ENOMEM;
552		goto err;
553	}
554	platform_set_drvdata(pdev, i2s);
555	i2s->dev = &pdev->dev;
556	dev_dbg(&pdev->dev, "dev: %p, i2s: %p\n", &pdev->dev, i2s);
557
558	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
559	i2s->regs = devm_ioremap_resource(&pdev->dev, mem);
560	if (IS_ERR(i2s->regs)) {
561		err = PTR_ERR(i2s->regs);
562		goto err;
563	}
564
565	i2s->regmap = devm_regmap_init_mmio(&pdev->dev, i2s->regs,
566					    &xtfpga_i2s_regmap_config);
567	if (IS_ERR(i2s->regmap)) {
568		dev_err(&pdev->dev, "regmap init failed\n");
569		err = PTR_ERR(i2s->regmap);
570		goto err;
571	}
572
573	i2s->clk = devm_clk_get(&pdev->dev, NULL);
574	if (IS_ERR(i2s->clk)) {
575		dev_err(&pdev->dev, "couldn't get clock\n");
576		err = PTR_ERR(i2s->clk);
577		goto err;
578	}
579
580	regmap_write(i2s->regmap, XTFPGA_I2S_CONFIG,
581		     (0x1 << XTFPGA_I2S_CONFIG_CHANNEL_BASE));
582	regmap_write(i2s->regmap, XTFPGA_I2S_INT_STATUS, XTFPGA_I2S_INT_VALID);
583	regmap_write(i2s->regmap, XTFPGA_I2S_INT_MASK, XTFPGA_I2S_INT_UNDERRUN);
584
585	irq = platform_get_irq(pdev, 0);
586	if (irq < 0) {
587		dev_err(&pdev->dev, "No IRQ resource\n");
588		err = irq;
589		goto err;
590	}
591	err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
592					xtfpga_i2s_threaded_irq_handler,
593					IRQF_SHARED | IRQF_ONESHOT,
594					pdev->name, i2s);
595	if (err < 0) {
596		dev_err(&pdev->dev, "request_irq failed\n");
597		goto err;
598	}
599
600	err = snd_soc_register_platform(&pdev->dev, &xtfpga_soc_platform);
601	if (err < 0) {
602		dev_err(&pdev->dev, "couldn't register platform\n");
603		goto err;
604	}
605	err = devm_snd_soc_register_component(&pdev->dev,
606					      &xtfpga_i2s_component,
607					      xtfpga_i2s_dai,
608					      ARRAY_SIZE(xtfpga_i2s_dai));
609	if (err < 0) {
610		dev_err(&pdev->dev, "couldn't register component\n");
611		goto err_unregister_platform;
612	}
613
614	pm_runtime_enable(&pdev->dev);
615	if (!pm_runtime_enabled(&pdev->dev)) {
616		err = xtfpga_i2s_runtime_resume(&pdev->dev);
617		if (err)
618			goto err_pm_disable;
619	}
620	return 0;
621
622err_pm_disable:
623	pm_runtime_disable(&pdev->dev);
624err_unregister_platform:
625	snd_soc_unregister_platform(&pdev->dev);
626err:
627	dev_err(&pdev->dev, "%s: err = %d\n", __func__, err);
628	return err;
629}
630
631static int xtfpga_i2s_remove(struct platform_device *pdev)
632{
633	struct xtfpga_i2s *i2s = dev_get_drvdata(&pdev->dev);
634
635	snd_soc_unregister_platform(&pdev->dev);
636	if (i2s->regmap && !IS_ERR(i2s->regmap)) {
637		regmap_write(i2s->regmap, XTFPGA_I2S_CONFIG, 0);
638		regmap_write(i2s->regmap, XTFPGA_I2S_INT_MASK, 0);
639		regmap_write(i2s->regmap, XTFPGA_I2S_INT_STATUS,
640			     XTFPGA_I2S_INT_VALID);
641	}
642	pm_runtime_disable(&pdev->dev);
643	if (!pm_runtime_status_suspended(&pdev->dev))
644		xtfpga_i2s_runtime_suspend(&pdev->dev);
645	return 0;
646}
647
648#ifdef CONFIG_OF
649static const struct of_device_id xtfpga_i2s_of_match[] = {
650	{ .compatible = "cdns,xtfpga-i2s", },
651	{},
652};
653MODULE_DEVICE_TABLE(of, xtfpga_i2s_of_match);
654#endif
655
656static const struct dev_pm_ops xtfpga_i2s_pm_ops = {
657	SET_RUNTIME_PM_OPS(xtfpga_i2s_runtime_suspend,
658			   xtfpga_i2s_runtime_resume, NULL)
659};
660
661static struct platform_driver xtfpga_i2s_driver = {
662	.probe   = xtfpga_i2s_probe,
663	.remove  = xtfpga_i2s_remove,
664	.driver  = {
665		.name = "xtfpga-i2s",
666		.of_match_table = of_match_ptr(xtfpga_i2s_of_match),
667		.pm = &xtfpga_i2s_pm_ops,
668	},
669};
670
671module_platform_driver(xtfpga_i2s_driver);
672
673MODULE_AUTHOR("Max Filippov <jcmvbkbc@gmail.com>");
674MODULE_DESCRIPTION("xtfpga I2S controller driver");
675MODULE_LICENSE("GPL v2");
676