xref: /linux/sound/soc/renesas/rz-ssi.c (revision 82a0a3e6f8c02b3236b55e784a083fa4ee07c321)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Renesas RZ/G2L ASoC Serial Sound Interface (SSIF-2) Driver
4 //
5 // Copyright (C) 2021 Renesas Electronics Corp.
6 // Copyright (C) 2019 Chris Brandt.
7 //
8 
9 #include <linux/clk.h>
10 #include <linux/dmaengine.h>
11 #include <linux/io.h>
12 #include <linux/iopoll.h>
13 #include <linux/module.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/reset.h>
16 #include <sound/soc.h>
17 
18 /* REGISTER OFFSET */
19 #define SSICR			0x000
20 #define SSISR			0x004
21 #define SSIFCR			0x010
22 #define SSIFSR			0x014
23 #define SSIFTDR			0x018
24 #define SSIFRDR			0x01c
25 #define SSIOFR			0x020
26 #define SSISCR			0x024
27 
28 /* SSI REGISTER BITS */
29 #define SSICR_DWL(x)		(((x) & 0x7) << 19)
30 #define SSICR_SWL(x)		(((x) & 0x7) << 16)
31 
32 #define SSICR_CKS		BIT(30)
33 #define SSICR_TUIEN		BIT(29)
34 #define SSICR_TOIEN		BIT(28)
35 #define SSICR_RUIEN		BIT(27)
36 #define SSICR_ROIEN		BIT(26)
37 #define SSICR_MST		BIT(14)
38 #define SSICR_BCKP		BIT(13)
39 #define SSICR_LRCKP		BIT(12)
40 #define SSICR_CKDV(x)		(((x) & 0xf) << 4)
41 #define SSICR_TEN		BIT(1)
42 #define SSICR_REN		BIT(0)
43 
44 #define SSISR_TUIRQ		BIT(29)
45 #define SSISR_TOIRQ		BIT(28)
46 #define SSISR_RUIRQ		BIT(27)
47 #define SSISR_ROIRQ		BIT(26)
48 #define SSISR_IIRQ		BIT(25)
49 
50 #define SSIFCR_AUCKE		BIT(31)
51 #define SSIFCR_SSIRST		BIT(16)
52 #define SSIFCR_TIE		BIT(3)
53 #define SSIFCR_RIE		BIT(2)
54 #define SSIFCR_TFRST		BIT(1)
55 #define SSIFCR_RFRST		BIT(0)
56 #define SSIFCR_FIFO_RST		(SSIFCR_TFRST | SSIFCR_RFRST)
57 
58 #define SSIFSR_TDC_MASK		0x3f
59 #define SSIFSR_TDC_SHIFT	24
60 #define SSIFSR_RDC_MASK		0x3f
61 #define SSIFSR_RDC_SHIFT	8
62 
63 #define SSIFSR_TDE		BIT(16)
64 #define SSIFSR_RDF		BIT(0)
65 
66 #define SSIOFR_LRCONT		BIT(8)
67 
68 #define SSISCR_TDES(x)		(((x) & 0x1f) << 8)
69 #define SSISCR_RDFS(x)		(((x) & 0x1f) << 0)
70 
71 /* Pre allocated buffers sizes */
72 #define PREALLOC_BUFFER		(SZ_32K)
73 #define PREALLOC_BUFFER_MAX	(SZ_32K)
74 
75 #define SSI_RATES		SNDRV_PCM_RATE_8000_48000 /* 8k-48kHz */
76 #define SSI_FMTS		SNDRV_PCM_FMTBIT_S16_LE
77 #define SSI_CHAN_MIN		2
78 #define SSI_CHAN_MAX		2
79 #define SSI_FIFO_DEPTH		32
80 
81 struct rz_ssi_priv;
82 
83 struct rz_ssi_stream {
84 	struct rz_ssi_priv *priv;
85 	struct snd_pcm_substream *substream;
86 	int fifo_sample_size;	/* sample capacity of SSI FIFO */
87 	int dma_buffer_pos;	/* The address for the next DMA descriptor */
88 	int period_counter;	/* for keeping track of periods transferred */
89 	int sample_width;
90 	int buffer_pos;		/* current frame position in the buffer */
91 	int running;		/* 0=stopped, 1=running */
92 
93 	int uerr_num;
94 	int oerr_num;
95 
96 	struct dma_chan *dma_ch;
97 
98 	int (*transfer)(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm);
99 };
100 
101 struct rz_ssi_priv {
102 	void __iomem *base;
103 	struct reset_control *rstc;
104 	struct device *dev;
105 	struct clk *sfr_clk;
106 	struct clk *clk;
107 
108 	phys_addr_t phys;
109 	int irq_int;
110 	int irq_tx;
111 	int irq_rx;
112 	int irq_rt;
113 
114 	spinlock_t lock;
115 
116 	/*
117 	 * The SSI supports full-duplex transmission and reception.
118 	 * However, if an error occurs, channel reset (both transmission
119 	 * and reception reset) is required.
120 	 * So it is better to use as half-duplex (playing and recording
121 	 * should be done on separate channels).
122 	 */
123 	struct rz_ssi_stream playback;
124 	struct rz_ssi_stream capture;
125 
126 	/* clock */
127 	unsigned long audio_mck;
128 	unsigned long audio_clk_1;
129 	unsigned long audio_clk_2;
130 
131 	bool lrckp_fsync_fall;	/* LR clock polarity (SSICR.LRCKP) */
132 	bool bckp_rise;	/* Bit clock polarity (SSICR.BCKP) */
133 	bool dma_rt;
134 
135 	/* Full duplex communication support */
136 	struct {
137 		unsigned int rate;
138 		unsigned int channels;
139 		unsigned int sample_width;
140 		unsigned int sample_bits;
141 	} hw_params_cache;
142 };
143 
144 static void rz_ssi_dma_complete(void *data);
145 
146 static void rz_ssi_reg_writel(struct rz_ssi_priv *priv, uint reg, u32 data)
147 {
148 	writel(data, (priv->base + reg));
149 }
150 
151 static u32 rz_ssi_reg_readl(struct rz_ssi_priv *priv, uint reg)
152 {
153 	return readl(priv->base + reg);
154 }
155 
156 static void rz_ssi_reg_mask_setl(struct rz_ssi_priv *priv, uint reg,
157 				 u32 bclr, u32 bset)
158 {
159 	u32 val;
160 
161 	val = readl(priv->base + reg);
162 	val = (val & ~bclr) | bset;
163 	writel(val, (priv->base + reg));
164 }
165 
166 static inline bool rz_ssi_stream_is_play(struct snd_pcm_substream *substream)
167 {
168 	return substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
169 }
170 
171 static inline struct rz_ssi_stream *
172 rz_ssi_stream_get(struct rz_ssi_priv *ssi, struct snd_pcm_substream *substream)
173 {
174 	struct rz_ssi_stream *stream = &ssi->playback;
175 
176 	if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
177 		stream = &ssi->capture;
178 
179 	return stream;
180 }
181 
182 static inline bool rz_ssi_is_dma_enabled(struct rz_ssi_priv *ssi)
183 {
184 	return (ssi->playback.dma_ch && (ssi->dma_rt || ssi->capture.dma_ch));
185 }
186 
187 static void rz_ssi_set_substream(struct rz_ssi_stream *strm,
188 				 struct snd_pcm_substream *substream)
189 {
190 	struct rz_ssi_priv *ssi = strm->priv;
191 	unsigned long flags;
192 
193 	spin_lock_irqsave(&ssi->lock, flags);
194 	strm->substream = substream;
195 	spin_unlock_irqrestore(&ssi->lock, flags);
196 }
197 
198 static bool rz_ssi_stream_is_valid(struct rz_ssi_priv *ssi,
199 				   struct rz_ssi_stream *strm)
200 {
201 	unsigned long flags;
202 	bool ret;
203 
204 	spin_lock_irqsave(&ssi->lock, flags);
205 	ret = strm->substream && strm->substream->runtime;
206 	spin_unlock_irqrestore(&ssi->lock, flags);
207 
208 	return ret;
209 }
210 
211 static inline bool rz_ssi_is_stream_running(struct rz_ssi_stream *strm)
212 {
213 	return strm->substream && strm->running;
214 }
215 
216 static void rz_ssi_stream_init(struct rz_ssi_stream *strm,
217 			       struct snd_pcm_substream *substream)
218 {
219 	struct snd_pcm_runtime *runtime = substream->runtime;
220 
221 	rz_ssi_set_substream(strm, substream);
222 	strm->sample_width = samples_to_bytes(runtime, 1);
223 	strm->dma_buffer_pos = 0;
224 	strm->period_counter = 0;
225 	strm->buffer_pos = 0;
226 
227 	strm->oerr_num = 0;
228 	strm->uerr_num = 0;
229 	strm->running = 0;
230 
231 	/* fifo init */
232 	strm->fifo_sample_size = SSI_FIFO_DEPTH;
233 }
234 
235 static void rz_ssi_stream_quit(struct rz_ssi_priv *ssi,
236 			       struct rz_ssi_stream *strm)
237 {
238 	struct device *dev = ssi->dev;
239 
240 	rz_ssi_set_substream(strm, NULL);
241 
242 	if (strm->oerr_num > 0)
243 		dev_info(dev, "overrun = %d\n", strm->oerr_num);
244 
245 	if (strm->uerr_num > 0)
246 		dev_info(dev, "underrun = %d\n", strm->uerr_num);
247 }
248 
249 static int rz_ssi_clk_setup(struct rz_ssi_priv *ssi, unsigned int rate,
250 			    unsigned int channels)
251 {
252 	static u8 ckdv[] = { 1,  2,  4,  8, 16, 32, 64, 128, 6, 12, 24, 48, 96 };
253 	unsigned int channel_bits = 32;	/* System Word Length */
254 	unsigned long bclk_rate = rate * channels * channel_bits;
255 	unsigned int div;
256 	unsigned int i;
257 	u32 ssicr = 0;
258 	u32 clk_ckdv;
259 
260 	/* Clear AUCKE so we can set MST */
261 	rz_ssi_reg_writel(ssi, SSIFCR, 0);
262 
263 	/* Continue to output LRCK pin even when idle */
264 	rz_ssi_reg_writel(ssi, SSIOFR, SSIOFR_LRCONT);
265 	if (ssi->audio_clk_1 && ssi->audio_clk_2) {
266 		if (ssi->audio_clk_1 % bclk_rate)
267 			ssi->audio_mck = ssi->audio_clk_2;
268 		else
269 			ssi->audio_mck = ssi->audio_clk_1;
270 	}
271 
272 	/* Clock setting */
273 	ssicr |= SSICR_MST;
274 	if (ssi->audio_mck == ssi->audio_clk_1)
275 		ssicr |= SSICR_CKS;
276 	if (ssi->bckp_rise)
277 		ssicr |= SSICR_BCKP;
278 	if (ssi->lrckp_fsync_fall)
279 		ssicr |= SSICR_LRCKP;
280 
281 	/* Determine the clock divider */
282 	clk_ckdv = 0;
283 	div = ssi->audio_mck / bclk_rate;
284 	/* try to find an match */
285 	for (i = 0; i < ARRAY_SIZE(ckdv); i++) {
286 		if (ckdv[i] == div) {
287 			clk_ckdv = i;
288 			break;
289 		}
290 	}
291 
292 	if (i == ARRAY_SIZE(ckdv)) {
293 		dev_err(ssi->dev, "Rate not divisible by audio clock source\n");
294 		return -EINVAL;
295 	}
296 
297 	/*
298 	 * DWL: Data Word Length = 16 bits
299 	 * SWL: System Word Length = 32 bits
300 	 */
301 	ssicr |= SSICR_CKDV(clk_ckdv);
302 	ssicr |= SSICR_DWL(1) | SSICR_SWL(3);
303 	rz_ssi_reg_writel(ssi, SSICR, ssicr);
304 	rz_ssi_reg_writel(ssi, SSIFCR, SSIFCR_AUCKE | SSIFCR_FIFO_RST);
305 
306 	return 0;
307 }
308 
309 static void rz_ssi_set_idle(struct rz_ssi_priv *ssi)
310 {
311 	u32 tmp;
312 	int ret;
313 
314 	/* Disable irqs */
315 	rz_ssi_reg_mask_setl(ssi, SSICR, SSICR_TUIEN | SSICR_TOIEN |
316 			     SSICR_RUIEN | SSICR_ROIEN, 0);
317 	rz_ssi_reg_mask_setl(ssi, SSIFCR, SSIFCR_TIE | SSIFCR_RIE, 0);
318 
319 	/* Clear all error flags */
320 	rz_ssi_reg_mask_setl(ssi, SSISR,
321 			     (SSISR_TOIRQ | SSISR_TUIRQ | SSISR_ROIRQ |
322 			      SSISR_RUIRQ), 0);
323 
324 	/* Wait for idle */
325 	ret = readl_poll_timeout_atomic(ssi->base + SSISR, tmp, (tmp & SSISR_IIRQ), 1, 100);
326 	if (ret)
327 		dev_warn_ratelimited(ssi->dev, "timeout waiting for SSI idle\n");
328 
329 	/* Hold FIFOs in reset */
330 	rz_ssi_reg_mask_setl(ssi, SSIFCR, 0, SSIFCR_FIFO_RST);
331 }
332 
333 static int rz_ssi_start(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
334 {
335 	bool is_play = rz_ssi_stream_is_play(strm->substream);
336 	bool is_full_duplex;
337 	u32 ssicr, ssifcr;
338 
339 	is_full_duplex = rz_ssi_is_stream_running(&ssi->playback) ||
340 		rz_ssi_is_stream_running(&ssi->capture);
341 	ssicr = rz_ssi_reg_readl(ssi, SSICR);
342 	ssifcr = rz_ssi_reg_readl(ssi, SSIFCR);
343 	if (!is_full_duplex) {
344 		ssifcr &= ~0xF;
345 	} else {
346 		rz_ssi_reg_mask_setl(ssi, SSICR, SSICR_TEN | SSICR_REN, 0);
347 		rz_ssi_set_idle(ssi);
348 		ssifcr &= ~SSIFCR_FIFO_RST;
349 	}
350 
351 	/* FIFO interrupt thresholds */
352 	if (rz_ssi_is_dma_enabled(ssi))
353 		rz_ssi_reg_writel(ssi, SSISCR, 0);
354 	else
355 		rz_ssi_reg_writel(ssi, SSISCR,
356 				  SSISCR_TDES(strm->fifo_sample_size / 2 - 1) |
357 				  SSISCR_RDFS(0));
358 
359 	/* enable IRQ */
360 	if (is_play) {
361 		ssicr |= SSICR_TUIEN | SSICR_TOIEN;
362 		ssifcr |= SSIFCR_TIE;
363 		if (!is_full_duplex)
364 			ssifcr |= SSIFCR_RFRST;
365 	} else {
366 		ssicr |= SSICR_RUIEN | SSICR_ROIEN;
367 		ssifcr |= SSIFCR_RIE;
368 		if (!is_full_duplex)
369 			ssifcr |= SSIFCR_TFRST;
370 	}
371 
372 	rz_ssi_reg_writel(ssi, SSICR, ssicr);
373 	rz_ssi_reg_writel(ssi, SSIFCR, ssifcr);
374 
375 	/* Clear all error flags */
376 	rz_ssi_reg_mask_setl(ssi, SSISR,
377 			     (SSISR_TOIRQ | SSISR_TUIRQ | SSISR_ROIRQ |
378 			      SSISR_RUIRQ), 0);
379 
380 	strm->running = 1;
381 	if (is_full_duplex)
382 		ssicr |= SSICR_TEN | SSICR_REN;
383 	else
384 		ssicr |= is_play ? SSICR_TEN : SSICR_REN;
385 
386 	rz_ssi_reg_writel(ssi, SSICR, ssicr);
387 
388 	return 0;
389 }
390 
391 static int rz_ssi_swreset(struct rz_ssi_priv *ssi)
392 {
393 	u32 tmp;
394 
395 	rz_ssi_reg_mask_setl(ssi, SSIFCR, 0, SSIFCR_SSIRST);
396 	rz_ssi_reg_mask_setl(ssi, SSIFCR, SSIFCR_SSIRST, 0);
397 	return readl_poll_timeout_atomic(ssi->base + SSIFCR, tmp, !(tmp & SSIFCR_SSIRST), 1, 5);
398 }
399 
400 static int rz_ssi_stop(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
401 {
402 	strm->running = 0;
403 
404 	if (rz_ssi_is_stream_running(&ssi->playback) ||
405 	    rz_ssi_is_stream_running(&ssi->capture))
406 		return 0;
407 
408 	/* Disable TX/RX */
409 	rz_ssi_reg_mask_setl(ssi, SSICR, SSICR_TEN | SSICR_REN, 0);
410 
411 	/* Cancel all remaining DMA transactions */
412 	if (rz_ssi_is_dma_enabled(ssi)) {
413 		if (ssi->playback.dma_ch)
414 			dmaengine_terminate_async(ssi->playback.dma_ch);
415 		if (ssi->capture.dma_ch)
416 			dmaengine_terminate_async(ssi->capture.dma_ch);
417 	}
418 
419 	rz_ssi_set_idle(ssi);
420 
421 	return 0;
422 }
423 
424 static void rz_ssi_pointer_update(struct rz_ssi_stream *strm, int frames)
425 {
426 	struct snd_pcm_substream *substream = strm->substream;
427 	struct snd_pcm_runtime *runtime;
428 	int current_period;
429 
430 	if (!strm->running || !substream || !substream->runtime)
431 		return;
432 
433 	runtime = substream->runtime;
434 	strm->buffer_pos += frames;
435 	WARN_ON(strm->buffer_pos > runtime->buffer_size);
436 
437 	/* ring buffer */
438 	if (strm->buffer_pos == runtime->buffer_size)
439 		strm->buffer_pos = 0;
440 
441 	current_period = strm->buffer_pos / runtime->period_size;
442 	if (strm->period_counter != current_period) {
443 		snd_pcm_period_elapsed(strm->substream);
444 		strm->period_counter = current_period;
445 	}
446 }
447 
448 static int rz_ssi_pio_recv(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
449 {
450 	struct snd_pcm_substream *substream = strm->substream;
451 	struct snd_pcm_runtime *runtime;
452 	u16 *buf;
453 	int fifo_samples;
454 	int frames_left;
455 	int samples;
456 	int i;
457 
458 	if (!rz_ssi_stream_is_valid(ssi, strm))
459 		return -EINVAL;
460 
461 	runtime = substream->runtime;
462 
463 	do {
464 		/* frames left in this period */
465 		frames_left = runtime->period_size -
466 			      (strm->buffer_pos % runtime->period_size);
467 		if (!frames_left)
468 			frames_left = runtime->period_size;
469 
470 		/* Samples in RX FIFO */
471 		fifo_samples = (rz_ssi_reg_readl(ssi, SSIFSR) >>
472 				SSIFSR_RDC_SHIFT) & SSIFSR_RDC_MASK;
473 
474 		/* Only read full frames at a time */
475 		samples = 0;
476 		while (frames_left && (fifo_samples >= runtime->channels)) {
477 			samples += runtime->channels;
478 			fifo_samples -= runtime->channels;
479 			frames_left--;
480 		}
481 
482 		/* not enough samples yet */
483 		if (!samples)
484 			break;
485 
486 		/* calculate new buffer index */
487 		buf = (u16 *)runtime->dma_area;
488 		buf += strm->buffer_pos * runtime->channels;
489 
490 		/* Note, only supports 16-bit samples */
491 		for (i = 0; i < samples; i++)
492 			*buf++ = (u16)(rz_ssi_reg_readl(ssi, SSIFRDR) >> 16);
493 
494 		rz_ssi_reg_mask_setl(ssi, SSIFSR, SSIFSR_RDF, 0);
495 		rz_ssi_pointer_update(strm, samples / runtime->channels);
496 	} while (!frames_left && fifo_samples >= runtime->channels);
497 
498 	return 0;
499 }
500 
501 static int rz_ssi_pio_send(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
502 {
503 	struct snd_pcm_substream *substream = strm->substream;
504 	struct snd_pcm_runtime *runtime = substream->runtime;
505 	int sample_space;
506 	int samples = 0;
507 	int frames_left;
508 	int i;
509 	u32 ssifsr;
510 	u16 *buf;
511 
512 	if (!rz_ssi_stream_is_valid(ssi, strm))
513 		return -EINVAL;
514 
515 	/* frames left in this period */
516 	frames_left = runtime->period_size - (strm->buffer_pos %
517 					      runtime->period_size);
518 	if (frames_left == 0)
519 		frames_left = runtime->period_size;
520 
521 	sample_space = strm->fifo_sample_size;
522 	ssifsr = rz_ssi_reg_readl(ssi, SSIFSR);
523 	sample_space -= (ssifsr >> SSIFSR_TDC_SHIFT) & SSIFSR_TDC_MASK;
524 	if (sample_space < 0)
525 		return -EINVAL;
526 
527 	/* Only add full frames at a time */
528 	while (frames_left && (sample_space >= runtime->channels)) {
529 		samples += runtime->channels;
530 		sample_space -= runtime->channels;
531 		frames_left--;
532 	}
533 
534 	/* no space to send anything right now */
535 	if (samples == 0)
536 		return 0;
537 
538 	/* calculate new buffer index */
539 	buf = (u16 *)(runtime->dma_area);
540 	buf += strm->buffer_pos * runtime->channels;
541 
542 	/* Note, only supports 16-bit samples */
543 	for (i = 0; i < samples; i++)
544 		rz_ssi_reg_writel(ssi, SSIFTDR, ((u32)(*buf++) << 16));
545 
546 	rz_ssi_reg_mask_setl(ssi, SSIFSR, SSIFSR_TDE, 0);
547 	rz_ssi_pointer_update(strm, samples / runtime->channels);
548 
549 	return 0;
550 }
551 
552 static irqreturn_t rz_ssi_interrupt(int irq, void *data)
553 {
554 	struct rz_ssi_stream *strm_playback = NULL;
555 	struct rz_ssi_stream *strm_capture = NULL;
556 	struct rz_ssi_priv *ssi = data;
557 	u32 ssisr = rz_ssi_reg_readl(ssi, SSISR);
558 
559 	if (ssi->playback.substream)
560 		strm_playback = &ssi->playback;
561 	if (ssi->capture.substream)
562 		strm_capture = &ssi->capture;
563 
564 	if (!strm_playback && !strm_capture)
565 		return IRQ_HANDLED; /* Left over TX/RX interrupt */
566 
567 	if (irq == ssi->irq_int) { /* error or idle */
568 		bool is_stopped = false;
569 		int i, count;
570 
571 		if (rz_ssi_is_dma_enabled(ssi))
572 			count = 4;
573 		else
574 			count = 1;
575 
576 		if (ssisr & (SSISR_RUIRQ | SSISR_ROIRQ | SSISR_TUIRQ | SSISR_TOIRQ))
577 			is_stopped = true;
578 
579 		if (ssi->capture.substream && is_stopped) {
580 			if (ssisr & SSISR_RUIRQ)
581 				strm_capture->uerr_num++;
582 			if (ssisr & SSISR_ROIRQ)
583 				strm_capture->oerr_num++;
584 
585 			rz_ssi_stop(ssi, strm_capture);
586 		}
587 
588 		if (ssi->playback.substream && is_stopped) {
589 			if (ssisr & SSISR_TUIRQ)
590 				strm_playback->uerr_num++;
591 			if (ssisr & SSISR_TOIRQ)
592 				strm_playback->oerr_num++;
593 
594 			rz_ssi_stop(ssi, strm_playback);
595 		}
596 
597 		/* Clear all flags */
598 		rz_ssi_reg_mask_setl(ssi, SSISR, SSISR_TOIRQ | SSISR_TUIRQ |
599 				     SSISR_ROIRQ | SSISR_RUIRQ, 0);
600 
601 		/* Add/remove more data */
602 		if (ssi->capture.substream && is_stopped) {
603 			for (i = 0; i < count; i++)
604 				strm_capture->transfer(ssi, strm_capture);
605 		}
606 
607 		if (ssi->playback.substream && is_stopped) {
608 			for (i = 0; i < count; i++)
609 				strm_playback->transfer(ssi, strm_playback);
610 		}
611 
612 		/* Resume */
613 		if (ssi->playback.substream && is_stopped)
614 			rz_ssi_start(ssi, &ssi->playback);
615 		if (ssi->capture.substream && is_stopped)
616 			rz_ssi_start(ssi, &ssi->capture);
617 	}
618 
619 	if (!rz_ssi_is_stream_running(&ssi->playback) &&
620 	    !rz_ssi_is_stream_running(&ssi->capture))
621 		return IRQ_HANDLED;
622 
623 	/* tx data empty */
624 	if (irq == ssi->irq_tx && rz_ssi_is_stream_running(&ssi->playback))
625 		strm_playback->transfer(ssi, &ssi->playback);
626 
627 	/* rx data full */
628 	if (irq == ssi->irq_rx && rz_ssi_is_stream_running(&ssi->capture)) {
629 		strm_capture->transfer(ssi, &ssi->capture);
630 		rz_ssi_reg_mask_setl(ssi, SSIFSR, SSIFSR_RDF, 0);
631 	}
632 
633 	if (irq == ssi->irq_rt) {
634 		if (ssi->playback.substream) {
635 			strm_playback->transfer(ssi, &ssi->playback);
636 		} else {
637 			strm_capture->transfer(ssi, &ssi->capture);
638 			rz_ssi_reg_mask_setl(ssi, SSIFSR, SSIFSR_RDF, 0);
639 		}
640 	}
641 
642 	return IRQ_HANDLED;
643 }
644 
645 static int rz_ssi_dma_slave_config(struct rz_ssi_priv *ssi,
646 				   struct dma_chan *dma_ch, bool is_play)
647 {
648 	struct dma_slave_config cfg;
649 
650 	memset(&cfg, 0, sizeof(cfg));
651 
652 	cfg.direction = is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
653 	cfg.dst_addr = ssi->phys + SSIFTDR;
654 	cfg.src_addr = ssi->phys + SSIFRDR;
655 	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
656 	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
657 
658 	return dmaengine_slave_config(dma_ch, &cfg);
659 }
660 
661 static int rz_ssi_dma_transfer(struct rz_ssi_priv *ssi,
662 			       struct rz_ssi_stream *strm)
663 {
664 	struct snd_pcm_substream *substream = strm->substream;
665 	struct dma_async_tx_descriptor *desc;
666 	struct snd_pcm_runtime *runtime;
667 	enum dma_transfer_direction dir;
668 	u32 dma_paddr, dma_size;
669 	int amount;
670 
671 	if (!rz_ssi_stream_is_valid(ssi, strm))
672 		return -EINVAL;
673 
674 	runtime = substream->runtime;
675 	if (runtime->state == SNDRV_PCM_STATE_DRAINING)
676 		/*
677 		 * Stream is ending, so do not queue up any more DMA
678 		 * transfers otherwise we play partial sound clips
679 		 * because we can't shut off the DMA quick enough.
680 		 */
681 		return 0;
682 
683 	dir = rz_ssi_stream_is_play(substream) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
684 
685 	/* Always transfer 1 period */
686 	amount = runtime->period_size;
687 
688 	/* DMA physical address and size */
689 	dma_paddr = runtime->dma_addr + frames_to_bytes(runtime,
690 							strm->dma_buffer_pos);
691 	dma_size = frames_to_bytes(runtime, amount);
692 	desc = dmaengine_prep_slave_single(strm->dma_ch, dma_paddr, dma_size,
693 					   dir,
694 					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
695 	if (!desc) {
696 		dev_err(ssi->dev, "dmaengine_prep_slave_single() fail\n");
697 		return -ENOMEM;
698 	}
699 
700 	desc->callback = rz_ssi_dma_complete;
701 	desc->callback_param = strm;
702 
703 	if (dmaengine_submit(desc) < 0) {
704 		dev_err(ssi->dev, "dmaengine_submit() fail\n");
705 		return -EIO;
706 	}
707 
708 	/* Update DMA pointer */
709 	strm->dma_buffer_pos += amount;
710 	if (strm->dma_buffer_pos >= runtime->buffer_size)
711 		strm->dma_buffer_pos = 0;
712 
713 	/* Start DMA */
714 	dma_async_issue_pending(strm->dma_ch);
715 
716 	return 0;
717 }
718 
719 static void rz_ssi_dma_complete(void *data)
720 {
721 	struct rz_ssi_stream *strm = (struct rz_ssi_stream *)data;
722 
723 	if (!strm->running || !strm->substream || !strm->substream->runtime)
724 		return;
725 
726 	/* Note that next DMA transaction has probably already started */
727 	rz_ssi_pointer_update(strm, strm->substream->runtime->period_size);
728 
729 	/* Queue up another DMA transaction */
730 	rz_ssi_dma_transfer(strm->priv, strm);
731 }
732 
733 static void rz_ssi_release_dma_channels(struct rz_ssi_priv *ssi)
734 {
735 	if (ssi->playback.dma_ch) {
736 		dma_release_channel(ssi->playback.dma_ch);
737 		ssi->playback.dma_ch = NULL;
738 		if (ssi->dma_rt)
739 			ssi->dma_rt = false;
740 	}
741 
742 	if (ssi->capture.dma_ch) {
743 		dma_release_channel(ssi->capture.dma_ch);
744 		ssi->capture.dma_ch = NULL;
745 	}
746 }
747 
748 static int rz_ssi_dma_request(struct rz_ssi_priv *ssi, struct device *dev)
749 {
750 	ssi->playback.dma_ch = dma_request_chan(dev, "tx");
751 	if (IS_ERR(ssi->playback.dma_ch))
752 		ssi->playback.dma_ch = NULL;
753 
754 	ssi->capture.dma_ch = dma_request_chan(dev, "rx");
755 	if (IS_ERR(ssi->capture.dma_ch))
756 		ssi->capture.dma_ch = NULL;
757 
758 	if (!ssi->playback.dma_ch && !ssi->capture.dma_ch) {
759 		ssi->playback.dma_ch = dma_request_chan(dev, "rt");
760 		if (IS_ERR(ssi->playback.dma_ch)) {
761 			ssi->playback.dma_ch = NULL;
762 			goto no_dma;
763 		}
764 
765 		ssi->dma_rt = true;
766 	}
767 
768 	if (!rz_ssi_is_dma_enabled(ssi))
769 		goto no_dma;
770 
771 	if (ssi->playback.dma_ch &&
772 	    (rz_ssi_dma_slave_config(ssi, ssi->playback.dma_ch, true) < 0))
773 		goto no_dma;
774 
775 	if (ssi->capture.dma_ch &&
776 	    (rz_ssi_dma_slave_config(ssi, ssi->capture.dma_ch, false) < 0))
777 		goto no_dma;
778 
779 	return 0;
780 
781 no_dma:
782 	rz_ssi_release_dma_channels(ssi);
783 
784 	return -ENODEV;
785 }
786 
787 static int rz_ssi_trigger_resume(struct rz_ssi_priv *ssi)
788 {
789 	int ret;
790 
791 	if (rz_ssi_is_stream_running(&ssi->playback) ||
792 	    rz_ssi_is_stream_running(&ssi->capture))
793 		return 0;
794 
795 	ret = rz_ssi_swreset(ssi);
796 	if (ret)
797 		return ret;
798 
799 	return rz_ssi_clk_setup(ssi, ssi->hw_params_cache.rate,
800 				ssi->hw_params_cache.channels);
801 }
802 
803 static void rz_ssi_streams_suspend(struct rz_ssi_priv *ssi)
804 {
805 	if (rz_ssi_is_stream_running(&ssi->playback) ||
806 	    rz_ssi_is_stream_running(&ssi->capture))
807 		return;
808 
809 	ssi->playback.dma_buffer_pos = 0;
810 	ssi->capture.dma_buffer_pos = 0;
811 }
812 
813 static int rz_ssi_dai_trigger(struct snd_pcm_substream *substream, int cmd,
814 			      struct snd_soc_dai *dai)
815 {
816 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
817 	struct rz_ssi_stream *strm = rz_ssi_stream_get(ssi, substream);
818 	int ret = 0, i, num_transfer = 1;
819 
820 	switch (cmd) {
821 	case SNDRV_PCM_TRIGGER_RESUME:
822 		ret = rz_ssi_trigger_resume(ssi);
823 		if (ret)
824 			return ret;
825 
826 		fallthrough;
827 
828 	case SNDRV_PCM_TRIGGER_START:
829 		if (cmd == SNDRV_PCM_TRIGGER_START)
830 			rz_ssi_stream_init(strm, substream);
831 
832 		if (ssi->dma_rt) {
833 			bool is_playback;
834 
835 			is_playback = rz_ssi_stream_is_play(substream);
836 			ret = rz_ssi_dma_slave_config(ssi, ssi->playback.dma_ch,
837 						      is_playback);
838 			/* Fallback to pio */
839 			if (ret < 0) {
840 				ssi->playback.transfer = rz_ssi_pio_send;
841 				ssi->capture.transfer = rz_ssi_pio_recv;
842 				rz_ssi_release_dma_channels(ssi);
843 			}
844 		}
845 
846 		/* For DMA, queue up multiple DMA descriptors */
847 		if (rz_ssi_is_dma_enabled(ssi))
848 			num_transfer = 4;
849 
850 		for (i = 0; i < num_transfer; i++) {
851 			ret = strm->transfer(ssi, strm);
852 			if (ret)
853 				goto done;
854 		}
855 
856 		ret = rz_ssi_start(ssi, strm);
857 		break;
858 
859 	case SNDRV_PCM_TRIGGER_SUSPEND:
860 		rz_ssi_stop(ssi, strm);
861 		rz_ssi_streams_suspend(ssi);
862 		break;
863 
864 	case SNDRV_PCM_TRIGGER_STOP:
865 		rz_ssi_stop(ssi, strm);
866 		rz_ssi_stream_quit(ssi, strm);
867 		break;
868 	}
869 
870 done:
871 	return ret;
872 }
873 
874 static int rz_ssi_dai_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
875 {
876 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
877 
878 	switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
879 	case SND_SOC_DAIFMT_BP_FP:
880 		break;
881 	default:
882 		dev_err(ssi->dev, "Codec should be clk and frame consumer\n");
883 		return -EINVAL;
884 	}
885 
886 	/*
887 	 * set clock polarity
888 	 *
889 	 * "normal" BCLK = Signal is available at rising edge of BCLK
890 	 * "normal" FSYNC = (I2S) Left ch starts with falling FSYNC edge
891 	 */
892 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
893 	case SND_SOC_DAIFMT_NB_NF:
894 		ssi->bckp_rise = false;
895 		ssi->lrckp_fsync_fall = false;
896 		break;
897 	case SND_SOC_DAIFMT_NB_IF:
898 		ssi->bckp_rise = false;
899 		ssi->lrckp_fsync_fall = true;
900 		break;
901 	case SND_SOC_DAIFMT_IB_NF:
902 		ssi->bckp_rise = true;
903 		ssi->lrckp_fsync_fall = false;
904 		break;
905 	case SND_SOC_DAIFMT_IB_IF:
906 		ssi->bckp_rise = true;
907 		ssi->lrckp_fsync_fall = true;
908 		break;
909 	default:
910 		return -EINVAL;
911 	}
912 
913 	/* only i2s support */
914 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
915 	case SND_SOC_DAIFMT_I2S:
916 		break;
917 	default:
918 		dev_err(ssi->dev, "Only I2S mode is supported.\n");
919 		return -EINVAL;
920 	}
921 
922 	return 0;
923 }
924 
925 static bool rz_ssi_is_valid_hw_params(struct rz_ssi_priv *ssi, unsigned int rate,
926 				      unsigned int channels,
927 				      unsigned int sample_width,
928 				      unsigned int sample_bits)
929 {
930 	if (ssi->hw_params_cache.rate != rate ||
931 	    ssi->hw_params_cache.channels != channels ||
932 	    ssi->hw_params_cache.sample_width != sample_width ||
933 	    ssi->hw_params_cache.sample_bits != sample_bits)
934 		return false;
935 
936 	return true;
937 }
938 
939 static void rz_ssi_cache_hw_params(struct rz_ssi_priv *ssi, unsigned int rate,
940 				   unsigned int channels,
941 				   unsigned int sample_width,
942 				   unsigned int sample_bits)
943 {
944 	ssi->hw_params_cache.rate = rate;
945 	ssi->hw_params_cache.channels = channels;
946 	ssi->hw_params_cache.sample_width = sample_width;
947 	ssi->hw_params_cache.sample_bits = sample_bits;
948 }
949 
950 static int rz_ssi_dai_hw_params(struct snd_pcm_substream *substream,
951 				struct snd_pcm_hw_params *params,
952 				struct snd_soc_dai *dai)
953 {
954 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
955 	struct rz_ssi_stream *strm = rz_ssi_stream_get(ssi, substream);
956 	unsigned int sample_bits = hw_param_interval(params,
957 					SNDRV_PCM_HW_PARAM_SAMPLE_BITS)->min;
958 	unsigned int channels = params_channels(params);
959 	unsigned int rate = params_rate(params);
960 	int ret;
961 
962 	if (sample_bits != 16) {
963 		dev_err(ssi->dev, "Unsupported sample width: %d\n",
964 			sample_bits);
965 		return -EINVAL;
966 	}
967 
968 	if (channels != 2) {
969 		dev_err(ssi->dev, "Number of channels not matched: %d\n",
970 			channels);
971 		return -EINVAL;
972 	}
973 
974 	if (rz_ssi_is_stream_running(&ssi->playback) ||
975 	    rz_ssi_is_stream_running(&ssi->capture)) {
976 		if (rz_ssi_is_valid_hw_params(ssi, rate, channels,
977 					      strm->sample_width, sample_bits))
978 			return 0;
979 
980 		dev_err(ssi->dev, "Full duplex needs same HW params\n");
981 		return -EINVAL;
982 	}
983 
984 	rz_ssi_cache_hw_params(ssi, rate, channels, strm->sample_width,
985 			       sample_bits);
986 
987 	ret = rz_ssi_swreset(ssi);
988 	if (ret)
989 		return ret;
990 
991 	return rz_ssi_clk_setup(ssi, rate, channels);
992 }
993 
994 static const struct snd_soc_dai_ops rz_ssi_dai_ops = {
995 	.trigger	= rz_ssi_dai_trigger,
996 	.set_fmt	= rz_ssi_dai_set_fmt,
997 	.hw_params	= rz_ssi_dai_hw_params,
998 };
999 
1000 static const struct snd_pcm_hardware rz_ssi_pcm_hardware = {
1001 	.info			= SNDRV_PCM_INFO_INTERLEAVED	|
1002 				  SNDRV_PCM_INFO_MMAP		|
1003 				  SNDRV_PCM_INFO_MMAP_VALID	|
1004 				  SNDRV_PCM_INFO_RESUME,
1005 	.buffer_bytes_max	= PREALLOC_BUFFER,
1006 	.period_bytes_min	= 32,
1007 	.period_bytes_max	= 8192,
1008 	.channels_min		= SSI_CHAN_MIN,
1009 	.channels_max		= SSI_CHAN_MAX,
1010 	.periods_min		= 1,
1011 	.periods_max		= 32,
1012 	.fifo_size		= 32 * 2,
1013 };
1014 
1015 static int rz_ssi_pcm_open(struct snd_soc_component *component,
1016 			   struct snd_pcm_substream *substream)
1017 {
1018 	snd_soc_set_runtime_hwparams(substream, &rz_ssi_pcm_hardware);
1019 
1020 	return snd_pcm_hw_constraint_integer(substream->runtime,
1021 					    SNDRV_PCM_HW_PARAM_PERIODS);
1022 }
1023 
1024 static snd_pcm_uframes_t rz_ssi_pcm_pointer(struct snd_soc_component *component,
1025 					    struct snd_pcm_substream *substream)
1026 {
1027 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
1028 	struct snd_soc_dai *dai = snd_soc_rtd_to_cpu(rtd, 0);
1029 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
1030 	struct rz_ssi_stream *strm = rz_ssi_stream_get(ssi, substream);
1031 
1032 	return strm->buffer_pos;
1033 }
1034 
1035 static int rz_ssi_pcm_new(struct snd_soc_component *component,
1036 			  struct snd_soc_pcm_runtime *rtd)
1037 {
1038 	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
1039 				       rtd->card->snd_card->dev,
1040 				       PREALLOC_BUFFER, PREALLOC_BUFFER_MAX);
1041 	return 0;
1042 }
1043 
1044 static struct snd_soc_dai_driver rz_ssi_soc_dai[] = {
1045 	{
1046 		.name			= "rz-ssi-dai",
1047 		.playback = {
1048 			.rates		= SSI_RATES,
1049 			.formats	= SSI_FMTS,
1050 			.channels_min	= SSI_CHAN_MIN,
1051 			.channels_max	= SSI_CHAN_MAX,
1052 		},
1053 		.capture = {
1054 			.rates		= SSI_RATES,
1055 			.formats	= SSI_FMTS,
1056 			.channels_min	= SSI_CHAN_MIN,
1057 			.channels_max	= SSI_CHAN_MAX,
1058 		},
1059 		.ops = &rz_ssi_dai_ops,
1060 	},
1061 };
1062 
1063 static const struct snd_soc_component_driver rz_ssi_soc_component = {
1064 	.name			= "rz-ssi",
1065 	.open			= rz_ssi_pcm_open,
1066 	.pointer		= rz_ssi_pcm_pointer,
1067 	.pcm_construct		= rz_ssi_pcm_new,
1068 	.legacy_dai_naming	= 1,
1069 };
1070 
1071 static int rz_ssi_probe(struct platform_device *pdev)
1072 {
1073 	struct device *dev = &pdev->dev;
1074 	struct rz_ssi_priv *ssi;
1075 	struct clk *audio_clk;
1076 	struct resource *res;
1077 	int ret;
1078 
1079 	ssi = devm_kzalloc(dev, sizeof(*ssi), GFP_KERNEL);
1080 	if (!ssi)
1081 		return -ENOMEM;
1082 
1083 	ssi->dev = dev;
1084 	ssi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1085 	if (IS_ERR(ssi->base))
1086 		return PTR_ERR(ssi->base);
1087 
1088 	ssi->phys = res->start;
1089 	ssi->clk = devm_clk_get(dev, "ssi");
1090 	if (IS_ERR(ssi->clk))
1091 		return PTR_ERR(ssi->clk);
1092 
1093 	ssi->sfr_clk = devm_clk_get(dev, "ssi_sfr");
1094 	if (IS_ERR(ssi->sfr_clk))
1095 		return PTR_ERR(ssi->sfr_clk);
1096 
1097 	audio_clk = devm_clk_get(dev, "audio_clk1");
1098 	if (IS_ERR(audio_clk))
1099 		return dev_err_probe(&pdev->dev, PTR_ERR(audio_clk),
1100 				     "no audio clk1");
1101 
1102 	ssi->audio_clk_1 = clk_get_rate(audio_clk);
1103 	audio_clk = devm_clk_get(dev, "audio_clk2");
1104 	if (IS_ERR(audio_clk))
1105 		return dev_err_probe(&pdev->dev, PTR_ERR(audio_clk),
1106 				     "no audio clk2");
1107 
1108 	ssi->audio_clk_2 = clk_get_rate(audio_clk);
1109 	if (!(ssi->audio_clk_1 || ssi->audio_clk_2))
1110 		return dev_err_probe(&pdev->dev, -EINVAL,
1111 				     "no audio clk1 or audio clk2");
1112 
1113 	ssi->audio_mck = ssi->audio_clk_1 ? ssi->audio_clk_1 : ssi->audio_clk_2;
1114 
1115 	/* Detect DMA support */
1116 	ret = rz_ssi_dma_request(ssi, dev);
1117 	if (ret < 0) {
1118 		dev_warn(dev, "DMA not available, using PIO\n");
1119 		ssi->playback.transfer = rz_ssi_pio_send;
1120 		ssi->capture.transfer = rz_ssi_pio_recv;
1121 	} else {
1122 		dev_info(dev, "DMA enabled");
1123 		ssi->playback.transfer = rz_ssi_dma_transfer;
1124 		ssi->capture.transfer = rz_ssi_dma_transfer;
1125 	}
1126 
1127 	ssi->playback.priv = ssi;
1128 	ssi->capture.priv = ssi;
1129 
1130 	spin_lock_init(&ssi->lock);
1131 	dev_set_drvdata(dev, ssi);
1132 
1133 	/* Error Interrupt */
1134 	ssi->irq_int = platform_get_irq_byname(pdev, "int_req");
1135 	if (ssi->irq_int < 0) {
1136 		ret = ssi->irq_int;
1137 		goto err_release_dma_chs;
1138 	}
1139 
1140 	ret = devm_request_irq(dev, ssi->irq_int, &rz_ssi_interrupt,
1141 			       0, dev_name(dev), ssi);
1142 	if (ret < 0) {
1143 		dev_err_probe(dev, ret, "irq request error (int_req)\n");
1144 		goto err_release_dma_chs;
1145 	}
1146 
1147 	if (!rz_ssi_is_dma_enabled(ssi)) {
1148 		/* Tx and Rx interrupts (pio only) */
1149 		ssi->irq_tx = platform_get_irq_byname(pdev, "dma_tx");
1150 		ssi->irq_rx = platform_get_irq_byname(pdev, "dma_rx");
1151 		if (ssi->irq_tx == -ENXIO && ssi->irq_rx == -ENXIO) {
1152 			ssi->irq_rt = platform_get_irq_byname(pdev, "dma_rt");
1153 			if (ssi->irq_rt < 0)
1154 				return ssi->irq_rt;
1155 
1156 			ret = devm_request_irq(dev, ssi->irq_rt,
1157 					       &rz_ssi_interrupt, 0,
1158 					       dev_name(dev), ssi);
1159 			if (ret < 0)
1160 				return dev_err_probe(dev, ret,
1161 						     "irq request error (dma_rt)\n");
1162 		} else {
1163 			if (ssi->irq_tx < 0)
1164 				return ssi->irq_tx;
1165 
1166 			if (ssi->irq_rx < 0)
1167 				return ssi->irq_rx;
1168 
1169 			ret = devm_request_irq(dev, ssi->irq_tx,
1170 					       &rz_ssi_interrupt, 0,
1171 					       dev_name(dev), ssi);
1172 			if (ret < 0)
1173 				return dev_err_probe(dev, ret,
1174 						"irq request error (dma_tx)\n");
1175 
1176 			ret = devm_request_irq(dev, ssi->irq_rx,
1177 					       &rz_ssi_interrupt, 0,
1178 					       dev_name(dev), ssi);
1179 			if (ret < 0)
1180 				return dev_err_probe(dev, ret,
1181 						"irq request error (dma_rx)\n");
1182 		}
1183 	}
1184 
1185 	ssi->rstc = devm_reset_control_get_exclusive(dev, NULL);
1186 	if (IS_ERR(ssi->rstc)) {
1187 		ret = PTR_ERR(ssi->rstc);
1188 		goto err_release_dma_chs;
1189 	}
1190 
1191 	/* Default 0 for power saving. Can be overridden via sysfs. */
1192 	pm_runtime_set_autosuspend_delay(dev, 0);
1193 	pm_runtime_use_autosuspend(dev);
1194 	ret = devm_pm_runtime_enable(dev);
1195 	if (ret < 0) {
1196 		dev_err(dev, "Failed to enable runtime PM!\n");
1197 		goto err_release_dma_chs;
1198 	}
1199 
1200 	ret = devm_snd_soc_register_component(dev, &rz_ssi_soc_component,
1201 					      rz_ssi_soc_dai,
1202 					      ARRAY_SIZE(rz_ssi_soc_dai));
1203 	if (ret < 0) {
1204 		dev_err(dev, "failed to register snd component\n");
1205 		goto err_release_dma_chs;
1206 	}
1207 
1208 	return 0;
1209 
1210 err_release_dma_chs:
1211 	rz_ssi_release_dma_channels(ssi);
1212 
1213 	return ret;
1214 }
1215 
1216 static void rz_ssi_remove(struct platform_device *pdev)
1217 {
1218 	struct rz_ssi_priv *ssi = dev_get_drvdata(&pdev->dev);
1219 
1220 	rz_ssi_release_dma_channels(ssi);
1221 
1222 	reset_control_assert(ssi->rstc);
1223 }
1224 
1225 static const struct of_device_id rz_ssi_of_match[] = {
1226 	{ .compatible = "renesas,rz-ssi", },
1227 	{/* Sentinel */},
1228 };
1229 MODULE_DEVICE_TABLE(of, rz_ssi_of_match);
1230 
1231 static int rz_ssi_runtime_suspend(struct device *dev)
1232 {
1233 	struct rz_ssi_priv *ssi = dev_get_drvdata(dev);
1234 
1235 	return reset_control_assert(ssi->rstc);
1236 }
1237 
1238 static int rz_ssi_runtime_resume(struct device *dev)
1239 {
1240 	struct rz_ssi_priv *ssi = dev_get_drvdata(dev);
1241 
1242 	return reset_control_deassert(ssi->rstc);
1243 }
1244 
1245 static const struct dev_pm_ops rz_ssi_pm_ops = {
1246 	RUNTIME_PM_OPS(rz_ssi_runtime_suspend, rz_ssi_runtime_resume, NULL)
1247 	SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
1248 };
1249 
1250 static struct platform_driver rz_ssi_driver = {
1251 	.driver	= {
1252 		.name	= "rz-ssi-pcm-audio",
1253 		.of_match_table = rz_ssi_of_match,
1254 		.pm = pm_ptr(&rz_ssi_pm_ops),
1255 	},
1256 	.probe		= rz_ssi_probe,
1257 	.remove		= rz_ssi_remove,
1258 };
1259 
1260 module_platform_driver(rz_ssi_driver);
1261 
1262 MODULE_LICENSE("GPL v2");
1263 MODULE_DESCRIPTION("Renesas RZ/G2L ASoC Serial Sound Interface Driver");
1264 MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
1265