xref: /linux/sound/soc/renesas/rz-ssi.c (revision 3f1c07fc21c68bd3bd2df9d2c9441f6485e934d9)
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/pcm_params.h>
17 #include <sound/soc.h>
18 
19 /* REGISTER OFFSET */
20 #define SSICR			0x000
21 #define SSISR			0x004
22 #define SSIFCR			0x010
23 #define SSIFSR			0x014
24 #define SSIFTDR			0x018
25 #define SSIFRDR			0x01c
26 #define SSIOFR			0x020
27 #define SSISCR			0x024
28 
29 /* SSI REGISTER BITS */
30 #define SSICR_DWL(x)		(((x) & 0x7) << 19)
31 #define SSICR_SWL(x)		(((x) & 0x7) << 16)
32 
33 #define SSICR_CKS		BIT(30)
34 #define SSICR_TUIEN		BIT(29)
35 #define SSICR_TOIEN		BIT(28)
36 #define SSICR_RUIEN		BIT(27)
37 #define SSICR_ROIEN		BIT(26)
38 #define SSICR_MST		BIT(14)
39 #define SSICR_BCKP		BIT(13)
40 #define SSICR_LRCKP		BIT(12)
41 #define SSICR_CKDV(x)		(((x) & 0xf) << 4)
42 #define SSICR_TEN		BIT(1)
43 #define SSICR_REN		BIT(0)
44 
45 #define SSISR_TUIRQ		BIT(29)
46 #define SSISR_TOIRQ		BIT(28)
47 #define SSISR_RUIRQ		BIT(27)
48 #define SSISR_ROIRQ		BIT(26)
49 #define SSISR_IIRQ		BIT(25)
50 
51 #define SSIFCR_AUCKE		BIT(31)
52 #define SSIFCR_SSIRST		BIT(16)
53 #define SSIFCR_TIE		BIT(3)
54 #define SSIFCR_RIE		BIT(2)
55 #define SSIFCR_TFRST		BIT(1)
56 #define SSIFCR_RFRST		BIT(0)
57 #define SSIFCR_FIFO_RST		(SSIFCR_TFRST | SSIFCR_RFRST)
58 
59 #define SSIFSR_TDC_MASK		0x3f
60 #define SSIFSR_TDC_SHIFT	24
61 #define SSIFSR_RDC_MASK		0x3f
62 #define SSIFSR_RDC_SHIFT	8
63 
64 #define SSIFSR_TDE		BIT(16)
65 #define SSIFSR_RDF		BIT(0)
66 
67 #define SSIOFR_LRCONT		BIT(8)
68 
69 #define SSISCR_TDES(x)		(((x) & 0x1f) << 8)
70 #define SSISCR_RDFS(x)		(((x) & 0x1f) << 0)
71 
72 /* Pre allocated buffers sizes */
73 #define PREALLOC_BUFFER		(SZ_32K)
74 #define PREALLOC_BUFFER_MAX	(SZ_32K)
75 
76 #define SSI_RATES		SNDRV_PCM_RATE_8000_48000 /* 8k-48kHz */
77 #define SSI_FMTS		SNDRV_PCM_FMTBIT_S16_LE
78 #define SSI_CHAN_MIN		2
79 #define SSI_CHAN_MAX		2
80 #define SSI_FIFO_DEPTH		32
81 
82 struct rz_ssi_priv;
83 
84 struct rz_ssi_stream {
85 	struct rz_ssi_priv *priv;
86 	struct snd_pcm_substream *substream;
87 	int fifo_sample_size;	/* sample capacity of SSI FIFO */
88 	int dma_buffer_pos;	/* The address for the next DMA descriptor */
89 	int completed_dma_buf_pos; /* The address of the last completed DMA descriptor. */
90 	int period_counter;	/* for keeping track of periods transferred */
91 	int buffer_pos;		/* current frame position in the buffer */
92 	int running;		/* 0=stopped, 1=running */
93 
94 	int uerr_num;
95 	int oerr_num;
96 
97 	struct dma_chan *dma_ch;
98 
99 	int (*transfer)(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm);
100 };
101 
102 struct rz_ssi_priv {
103 	void __iomem *base;
104 	struct reset_control *rstc;
105 	struct device *dev;
106 	struct clk *sfr_clk;
107 	struct clk *clk;
108 
109 	phys_addr_t phys;
110 	int irq_int;
111 	int irq_tx;
112 	int irq_rx;
113 	int irq_rt;
114 
115 	spinlock_t lock;
116 
117 	/*
118 	 * The SSI supports full-duplex transmission and reception.
119 	 * However, if an error occurs, channel reset (both transmission
120 	 * and reception reset) is required.
121 	 * So it is better to use as half-duplex (playing and recording
122 	 * should be done on separate channels).
123 	 */
124 	struct rz_ssi_stream playback;
125 	struct rz_ssi_stream capture;
126 
127 	/* clock */
128 	unsigned long audio_mck;
129 	unsigned long audio_clk_1;
130 	unsigned long audio_clk_2;
131 
132 	bool lrckp_fsync_fall;	/* LR clock polarity (SSICR.LRCKP) */
133 	bool bckp_rise;	/* Bit clock polarity (SSICR.BCKP) */
134 	bool dma_rt;
135 
136 	struct {
137 		bool tx_active;
138 		bool rx_active;
139 		bool one_stream_triggered;
140 	} dup;
141 
142 	/* Full duplex communication support */
143 	struct {
144 		unsigned int rate;
145 		unsigned int channels;
146 		unsigned int sample_width;
147 		unsigned int sample_bits;
148 	} hw_params_cache;
149 };
150 
151 static void rz_ssi_dma_complete(void *data);
152 
rz_ssi_reg_writel(struct rz_ssi_priv * priv,uint reg,u32 data)153 static void rz_ssi_reg_writel(struct rz_ssi_priv *priv, uint reg, u32 data)
154 {
155 	writel(data, (priv->base + reg));
156 }
157 
rz_ssi_reg_readl(struct rz_ssi_priv * priv,uint reg)158 static u32 rz_ssi_reg_readl(struct rz_ssi_priv *priv, uint reg)
159 {
160 	return readl(priv->base + reg);
161 }
162 
rz_ssi_reg_mask_setl(struct rz_ssi_priv * priv,uint reg,u32 bclr,u32 bset)163 static void rz_ssi_reg_mask_setl(struct rz_ssi_priv *priv, uint reg,
164 				 u32 bclr, u32 bset)
165 {
166 	u32 val;
167 
168 	val = readl(priv->base + reg);
169 	val = (val & ~bclr) | bset;
170 	writel(val, (priv->base + reg));
171 }
172 
rz_ssi_stream_is_play(struct snd_pcm_substream * substream)173 static inline bool rz_ssi_stream_is_play(struct snd_pcm_substream *substream)
174 {
175 	return substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
176 }
177 
178 static inline struct rz_ssi_stream *
rz_ssi_stream_get(struct rz_ssi_priv * ssi,struct snd_pcm_substream * substream)179 rz_ssi_stream_get(struct rz_ssi_priv *ssi, struct snd_pcm_substream *substream)
180 {
181 	struct rz_ssi_stream *stream = &ssi->playback;
182 
183 	if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
184 		stream = &ssi->capture;
185 
186 	return stream;
187 }
188 
rz_ssi_is_dma_enabled(struct rz_ssi_priv * ssi)189 static inline bool rz_ssi_is_dma_enabled(struct rz_ssi_priv *ssi)
190 {
191 	return (ssi->playback.dma_ch && (ssi->dma_rt || ssi->capture.dma_ch));
192 }
193 
rz_ssi_set_substream(struct rz_ssi_stream * strm,struct snd_pcm_substream * substream)194 static void rz_ssi_set_substream(struct rz_ssi_stream *strm,
195 				 struct snd_pcm_substream *substream)
196 {
197 	struct rz_ssi_priv *ssi = strm->priv;
198 
199 	guard(spinlock_irqsave)(&ssi->lock);
200 
201 	strm->substream = substream;
202 }
203 
rz_ssi_stream_is_valid(struct rz_ssi_priv * ssi,struct rz_ssi_stream * strm)204 static bool rz_ssi_stream_is_valid(struct rz_ssi_priv *ssi,
205 				   struct rz_ssi_stream *strm)
206 {
207 	guard(spinlock_irqsave)(&ssi->lock);
208 
209 	return strm->substream && strm->substream->runtime;
210 }
211 
rz_ssi_is_stream_running(struct rz_ssi_stream * strm)212 static inline bool rz_ssi_is_stream_running(struct rz_ssi_stream *strm)
213 {
214 	return strm->substream && strm->running;
215 }
216 
rz_ssi_stream_init(struct rz_ssi_stream * strm,struct snd_pcm_substream * substream)217 static void rz_ssi_stream_init(struct rz_ssi_stream *strm,
218 			       struct snd_pcm_substream *substream)
219 {
220 	rz_ssi_set_substream(strm, substream);
221 	strm->dma_buffer_pos = 0;
222 	strm->completed_dma_buf_pos = 0;
223 	strm->period_counter = 0;
224 	strm->buffer_pos = 0;
225 
226 	strm->oerr_num = 0;
227 	strm->uerr_num = 0;
228 	strm->running = 0;
229 
230 	/* fifo init */
231 	strm->fifo_sample_size = SSI_FIFO_DEPTH;
232 }
233 
rz_ssi_stream_quit(struct rz_ssi_priv * ssi,struct rz_ssi_stream * strm)234 static void rz_ssi_stream_quit(struct rz_ssi_priv *ssi,
235 			       struct rz_ssi_stream *strm)
236 {
237 	struct device *dev = ssi->dev;
238 
239 	rz_ssi_set_substream(strm, NULL);
240 
241 	if (strm->oerr_num > 0)
242 		dev_info(dev, "overrun = %d\n", strm->oerr_num);
243 
244 	if (strm->uerr_num > 0)
245 		dev_info(dev, "underrun = %d\n", strm->uerr_num);
246 }
247 
rz_ssi_clk_setup(struct rz_ssi_priv * ssi,unsigned int rate,unsigned int channels)248 static int rz_ssi_clk_setup(struct rz_ssi_priv *ssi, unsigned int rate,
249 			    unsigned int channels)
250 {
251 	static u8 ckdv[] = { 1,  2,  4,  8, 16, 32, 64, 128, 6, 12, 24, 48, 96 };
252 	unsigned int channel_bits = 32;	/* System Word Length */
253 	unsigned long bclk_rate = rate * channels * channel_bits;
254 	unsigned int div;
255 	unsigned int i;
256 	u32 ssicr = 0;
257 	u32 clk_ckdv;
258 
259 	/* Clear AUCKE so we can set MST */
260 	rz_ssi_reg_writel(ssi, SSIFCR, 0);
261 
262 	/* Continue to output LRCK pin even when idle */
263 	rz_ssi_reg_writel(ssi, SSIOFR, SSIOFR_LRCONT);
264 	if (ssi->audio_clk_1 && ssi->audio_clk_2) {
265 		if (ssi->audio_clk_1 % bclk_rate)
266 			ssi->audio_mck = ssi->audio_clk_2;
267 		else
268 			ssi->audio_mck = ssi->audio_clk_1;
269 	}
270 
271 	/* Clock setting */
272 	ssicr |= SSICR_MST;
273 	if (ssi->audio_mck == ssi->audio_clk_1)
274 		ssicr |= SSICR_CKS;
275 	if (ssi->bckp_rise)
276 		ssicr |= SSICR_BCKP;
277 	if (ssi->lrckp_fsync_fall)
278 		ssicr |= SSICR_LRCKP;
279 
280 	/* Determine the clock divider */
281 	clk_ckdv = 0;
282 	div = ssi->audio_mck / bclk_rate;
283 	/* try to find an match */
284 	for (i = 0; i < ARRAY_SIZE(ckdv); i++) {
285 		if (ckdv[i] == div) {
286 			clk_ckdv = i;
287 			break;
288 		}
289 	}
290 
291 	if (i == ARRAY_SIZE(ckdv)) {
292 		dev_err(ssi->dev, "Rate not divisible by audio clock source\n");
293 		return -EINVAL;
294 	}
295 
296 	/*
297 	 * DWL: Data Word Length = 16 bits
298 	 * SWL: System Word Length = 32 bits
299 	 */
300 	ssicr |= SSICR_CKDV(clk_ckdv);
301 	ssicr |= SSICR_DWL(1) | SSICR_SWL(3);
302 	rz_ssi_reg_writel(ssi, SSICR, ssicr);
303 	rz_ssi_reg_writel(ssi, SSIFCR, SSIFCR_AUCKE | SSIFCR_FIFO_RST);
304 
305 	return 0;
306 }
307 
rz_ssi_set_idle(struct rz_ssi_priv * ssi)308 static void rz_ssi_set_idle(struct rz_ssi_priv *ssi)
309 {
310 	u32 tmp;
311 	int ret;
312 
313 	/* Disable irqs */
314 	rz_ssi_reg_mask_setl(ssi, SSICR, SSICR_TUIEN | SSICR_TOIEN |
315 			     SSICR_RUIEN | SSICR_ROIEN, 0);
316 	rz_ssi_reg_mask_setl(ssi, SSIFCR, SSIFCR_TIE | SSIFCR_RIE, 0);
317 
318 	/* Clear all error flags */
319 	rz_ssi_reg_mask_setl(ssi, SSISR,
320 			     (SSISR_TOIRQ | SSISR_TUIRQ | SSISR_ROIRQ |
321 			      SSISR_RUIRQ), 0);
322 
323 	/* Wait for idle */
324 	ret = readl_poll_timeout_atomic(ssi->base + SSISR, tmp, (tmp & SSISR_IIRQ), 1, 100);
325 	if (ret)
326 		dev_warn_ratelimited(ssi->dev, "timeout waiting for SSI idle\n");
327 
328 	/* Hold FIFOs in reset */
329 	rz_ssi_reg_mask_setl(ssi, SSIFCR, 0, SSIFCR_FIFO_RST);
330 }
331 
rz_ssi_start(struct rz_ssi_priv * ssi,struct rz_ssi_stream * strm)332 static int rz_ssi_start(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
333 {
334 	bool is_play = rz_ssi_stream_is_play(strm->substream);
335 	bool is_full_duplex;
336 	u32 ssicr, ssifcr;
337 
338 	is_full_duplex = ssi->dup.tx_active && ssi->dup.rx_active;
339 	ssicr = rz_ssi_reg_readl(ssi, SSICR);
340 	ssifcr = rz_ssi_reg_readl(ssi, SSIFCR);
341 	if (!is_full_duplex) {
342 		ssifcr &= ~0xF;
343 	} else if (ssi->dup.one_stream_triggered) {
344 		rz_ssi_reg_mask_setl(ssi, SSICR, SSICR_TEN | SSICR_REN, 0);
345 		rz_ssi_set_idle(ssi);
346 		ssifcr &= ~SSIFCR_FIFO_RST;
347 	}
348 
349 	/* FIFO interrupt thresholds */
350 	if (rz_ssi_is_dma_enabled(ssi))
351 		rz_ssi_reg_writel(ssi, SSISCR, 0);
352 	else
353 		rz_ssi_reg_writel(ssi, SSISCR,
354 				  SSISCR_TDES(strm->fifo_sample_size / 2 - 1) |
355 				  SSISCR_RDFS(0));
356 
357 	/* enable IRQ */
358 	if (is_play) {
359 		ssicr |= SSICR_TUIEN | SSICR_TOIEN;
360 		ssifcr |= SSIFCR_TIE;
361 		if (!is_full_duplex)
362 			ssifcr |= SSIFCR_RFRST;
363 	} else {
364 		ssicr |= SSICR_RUIEN | SSICR_ROIEN;
365 		ssifcr |= SSIFCR_RIE;
366 		if (!is_full_duplex)
367 			ssifcr |= SSIFCR_TFRST;
368 	}
369 
370 	rz_ssi_reg_writel(ssi, SSICR, ssicr);
371 	rz_ssi_reg_writel(ssi, SSIFCR, ssifcr);
372 
373 	/* Clear all error flags */
374 	rz_ssi_reg_mask_setl(ssi, SSISR,
375 			     (SSISR_TOIRQ | SSISR_TUIRQ | SSISR_ROIRQ |
376 			      SSISR_RUIRQ), 0);
377 
378 	strm->running = 1;
379 	if (!is_full_duplex) {
380 		ssicr |= is_play ? SSICR_TEN : SSICR_REN;
381 		rz_ssi_reg_writel(ssi, SSICR, ssicr);
382 	} else if (ssi->dup.one_stream_triggered) {
383 		ssicr |= SSICR_TEN | SSICR_REN;
384 		rz_ssi_reg_writel(ssi, SSICR, ssicr);
385 		ssi->dup.one_stream_triggered = false;
386 	} else {
387 		ssi->dup.one_stream_triggered = true;
388 	}
389 
390 	return 0;
391 }
392 
rz_ssi_swreset(struct rz_ssi_priv * ssi)393 static int rz_ssi_swreset(struct rz_ssi_priv *ssi)
394 {
395 	u32 tmp;
396 
397 	rz_ssi_reg_mask_setl(ssi, SSIFCR, 0, SSIFCR_SSIRST);
398 	rz_ssi_reg_mask_setl(ssi, SSIFCR, SSIFCR_SSIRST, 0);
399 	return readl_poll_timeout_atomic(ssi->base + SSIFCR, tmp, !(tmp & SSIFCR_SSIRST), 1, 5);
400 }
401 
rz_ssi_stop(struct rz_ssi_priv * ssi,struct rz_ssi_stream * strm)402 static int rz_ssi_stop(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
403 {
404 	strm->running = 0;
405 
406 	if (rz_ssi_is_stream_running(&ssi->playback) ||
407 	    rz_ssi_is_stream_running(&ssi->capture))
408 		return 0;
409 
410 	/* Disable TX/RX */
411 	rz_ssi_reg_mask_setl(ssi, SSICR, SSICR_TEN | SSICR_REN, 0);
412 
413 	/* Cancel all remaining DMA transactions */
414 	if (rz_ssi_is_dma_enabled(ssi)) {
415 		if (ssi->playback.dma_ch)
416 			dmaengine_terminate_async(ssi->playback.dma_ch);
417 		if (ssi->capture.dma_ch)
418 			dmaengine_terminate_async(ssi->capture.dma_ch);
419 	}
420 
421 	rz_ssi_set_idle(ssi);
422 
423 	return 0;
424 }
425 
rz_ssi_pointer_update(struct rz_ssi_stream * strm,int frames)426 static void rz_ssi_pointer_update(struct rz_ssi_stream *strm, int frames)
427 {
428 	struct snd_pcm_substream *substream = strm->substream;
429 	struct snd_pcm_runtime *runtime;
430 	int current_period;
431 
432 	if (!strm->running || !substream || !substream->runtime)
433 		return;
434 
435 	runtime = substream->runtime;
436 	strm->buffer_pos += frames;
437 	WARN_ON(strm->buffer_pos > runtime->buffer_size);
438 
439 	/* ring buffer */
440 	if (strm->buffer_pos == runtime->buffer_size)
441 		strm->buffer_pos = 0;
442 
443 	current_period = strm->buffer_pos / runtime->period_size;
444 	if (strm->period_counter != current_period) {
445 		snd_pcm_period_elapsed(strm->substream);
446 		strm->period_counter = current_period;
447 	}
448 
449 	strm->completed_dma_buf_pos += runtime->period_size;
450 	if (strm->completed_dma_buf_pos >= runtime->buffer_size)
451 		strm->completed_dma_buf_pos = 0;
452 }
453 
rz_ssi_pio_recv(struct rz_ssi_priv * ssi,struct rz_ssi_stream * strm)454 static int rz_ssi_pio_recv(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
455 {
456 	struct snd_pcm_substream *substream = strm->substream;
457 	struct snd_pcm_runtime *runtime;
458 	u16 *buf;
459 	int fifo_samples;
460 	int frames_left;
461 	int samples;
462 	int i;
463 
464 	if (!rz_ssi_stream_is_valid(ssi, strm))
465 		return -EINVAL;
466 
467 	runtime = substream->runtime;
468 
469 	do {
470 		/* frames left in this period */
471 		frames_left = runtime->period_size -
472 			      (strm->buffer_pos % runtime->period_size);
473 		if (!frames_left)
474 			frames_left = runtime->period_size;
475 
476 		/* Samples in RX FIFO */
477 		fifo_samples = (rz_ssi_reg_readl(ssi, SSIFSR) >>
478 				SSIFSR_RDC_SHIFT) & SSIFSR_RDC_MASK;
479 
480 		/* Only read full frames at a time */
481 		samples = 0;
482 		while (frames_left && (fifo_samples >= runtime->channels)) {
483 			samples += runtime->channels;
484 			fifo_samples -= runtime->channels;
485 			frames_left--;
486 		}
487 
488 		/* not enough samples yet */
489 		if (!samples)
490 			break;
491 
492 		/* calculate new buffer index */
493 		buf = (u16 *)runtime->dma_area;
494 		buf += strm->buffer_pos * runtime->channels;
495 
496 		/* Note, only supports 16-bit samples */
497 		for (i = 0; i < samples; i++)
498 			*buf++ = (u16)(rz_ssi_reg_readl(ssi, SSIFRDR) >> 16);
499 
500 		rz_ssi_reg_mask_setl(ssi, SSIFSR, SSIFSR_RDF, 0);
501 		rz_ssi_pointer_update(strm, samples / runtime->channels);
502 	} while (!frames_left && fifo_samples >= runtime->channels);
503 
504 	return 0;
505 }
506 
rz_ssi_pio_send(struct rz_ssi_priv * ssi,struct rz_ssi_stream * strm)507 static int rz_ssi_pio_send(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
508 {
509 	struct snd_pcm_substream *substream = strm->substream;
510 	struct snd_pcm_runtime *runtime = substream->runtime;
511 	int sample_space;
512 	int samples = 0;
513 	int frames_left;
514 	int i;
515 	u32 ssifsr;
516 	u16 *buf;
517 
518 	if (!rz_ssi_stream_is_valid(ssi, strm))
519 		return -EINVAL;
520 
521 	/* frames left in this period */
522 	frames_left = runtime->period_size - (strm->buffer_pos %
523 					      runtime->period_size);
524 	if (frames_left == 0)
525 		frames_left = runtime->period_size;
526 
527 	sample_space = strm->fifo_sample_size;
528 	ssifsr = rz_ssi_reg_readl(ssi, SSIFSR);
529 	sample_space -= (ssifsr >> SSIFSR_TDC_SHIFT) & SSIFSR_TDC_MASK;
530 	if (sample_space < 0)
531 		return -EINVAL;
532 
533 	/* Only add full frames at a time */
534 	while (frames_left && (sample_space >= runtime->channels)) {
535 		samples += runtime->channels;
536 		sample_space -= runtime->channels;
537 		frames_left--;
538 	}
539 
540 	/* no space to send anything right now */
541 	if (samples == 0)
542 		return 0;
543 
544 	/* calculate new buffer index */
545 	buf = (u16 *)(runtime->dma_area);
546 	buf += strm->buffer_pos * runtime->channels;
547 
548 	/* Note, only supports 16-bit samples */
549 	for (i = 0; i < samples; i++)
550 		rz_ssi_reg_writel(ssi, SSIFTDR, ((u32)(*buf++) << 16));
551 
552 	rz_ssi_reg_mask_setl(ssi, SSIFSR, SSIFSR_TDE, 0);
553 	rz_ssi_pointer_update(strm, samples / runtime->channels);
554 
555 	return 0;
556 }
557 
rz_ssi_interrupt(int irq,void * data)558 static irqreturn_t rz_ssi_interrupt(int irq, void *data)
559 {
560 	struct rz_ssi_stream *strm_playback = NULL;
561 	struct rz_ssi_stream *strm_capture = NULL;
562 	struct rz_ssi_priv *ssi = data;
563 	u32 ssisr = rz_ssi_reg_readl(ssi, SSISR);
564 
565 	if (ssi->playback.substream)
566 		strm_playback = &ssi->playback;
567 	if (ssi->capture.substream)
568 		strm_capture = &ssi->capture;
569 
570 	if (!strm_playback && !strm_capture)
571 		return IRQ_HANDLED; /* Left over TX/RX interrupt */
572 
573 	if (irq == ssi->irq_int) { /* error or idle */
574 		bool is_stopped = false;
575 		int i, count;
576 
577 		if (rz_ssi_is_dma_enabled(ssi))
578 			count = 4;
579 		else
580 			count = 1;
581 
582 		if (ssisr & (SSISR_RUIRQ | SSISR_ROIRQ | SSISR_TUIRQ | SSISR_TOIRQ))
583 			is_stopped = true;
584 
585 		if (ssi->capture.substream && is_stopped) {
586 			if (ssisr & SSISR_RUIRQ)
587 				strm_capture->uerr_num++;
588 			if (ssisr & SSISR_ROIRQ)
589 				strm_capture->oerr_num++;
590 
591 			rz_ssi_stop(ssi, strm_capture);
592 		}
593 
594 		if (ssi->playback.substream && is_stopped) {
595 			if (ssisr & SSISR_TUIRQ)
596 				strm_playback->uerr_num++;
597 			if (ssisr & SSISR_TOIRQ)
598 				strm_playback->oerr_num++;
599 
600 			rz_ssi_stop(ssi, strm_playback);
601 		}
602 
603 		/* Clear all flags */
604 		rz_ssi_reg_mask_setl(ssi, SSISR, SSISR_TOIRQ | SSISR_TUIRQ |
605 				     SSISR_ROIRQ | SSISR_RUIRQ, 0);
606 
607 		/* Add/remove more data */
608 		if (ssi->capture.substream && is_stopped) {
609 			for (i = 0; i < count; i++)
610 				strm_capture->transfer(ssi, strm_capture);
611 		}
612 
613 		if (ssi->playback.substream && is_stopped) {
614 			for (i = 0; i < count; i++)
615 				strm_playback->transfer(ssi, strm_playback);
616 		}
617 
618 		/* Resume */
619 		if (ssi->playback.substream && is_stopped)
620 			rz_ssi_start(ssi, &ssi->playback);
621 		if (ssi->capture.substream && is_stopped)
622 			rz_ssi_start(ssi, &ssi->capture);
623 	}
624 
625 	if (!rz_ssi_is_stream_running(&ssi->playback) &&
626 	    !rz_ssi_is_stream_running(&ssi->capture))
627 		return IRQ_HANDLED;
628 
629 	/* tx data empty */
630 	if (irq == ssi->irq_tx && rz_ssi_is_stream_running(&ssi->playback))
631 		strm_playback->transfer(ssi, &ssi->playback);
632 
633 	/* rx data full */
634 	if (irq == ssi->irq_rx && rz_ssi_is_stream_running(&ssi->capture)) {
635 		strm_capture->transfer(ssi, &ssi->capture);
636 		rz_ssi_reg_mask_setl(ssi, SSIFSR, SSIFSR_RDF, 0);
637 	}
638 
639 	if (irq == ssi->irq_rt) {
640 		if (ssi->playback.substream) {
641 			strm_playback->transfer(ssi, &ssi->playback);
642 		} else {
643 			strm_capture->transfer(ssi, &ssi->capture);
644 			rz_ssi_reg_mask_setl(ssi, SSIFSR, SSIFSR_RDF, 0);
645 		}
646 	}
647 
648 	return IRQ_HANDLED;
649 }
650 
rz_ssi_dma_slave_config(struct rz_ssi_priv * ssi,struct dma_chan * dma_ch,bool is_play)651 static int rz_ssi_dma_slave_config(struct rz_ssi_priv *ssi,
652 				   struct dma_chan *dma_ch, bool is_play)
653 {
654 	struct dma_slave_config cfg;
655 
656 	memset(&cfg, 0, sizeof(cfg));
657 
658 	cfg.direction = is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
659 	cfg.dst_addr = ssi->phys + SSIFTDR;
660 	cfg.src_addr = ssi->phys + SSIFRDR;
661 	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
662 	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
663 
664 	return dmaengine_slave_config(dma_ch, &cfg);
665 }
666 
rz_ssi_dma_transfer(struct rz_ssi_priv * ssi,struct rz_ssi_stream * strm)667 static int rz_ssi_dma_transfer(struct rz_ssi_priv *ssi,
668 			       struct rz_ssi_stream *strm)
669 {
670 	struct snd_pcm_substream *substream = strm->substream;
671 	struct dma_async_tx_descriptor *desc;
672 	struct snd_pcm_runtime *runtime;
673 	enum dma_transfer_direction dir;
674 	u32 dma_paddr, dma_size;
675 	int amount;
676 
677 	if (!rz_ssi_stream_is_valid(ssi, strm))
678 		return -EINVAL;
679 
680 	runtime = substream->runtime;
681 	if (runtime->state == SNDRV_PCM_STATE_DRAINING)
682 		/*
683 		 * Stream is ending, so do not queue up any more DMA
684 		 * transfers otherwise we play partial sound clips
685 		 * because we can't shut off the DMA quick enough.
686 		 */
687 		return 0;
688 
689 	dir = rz_ssi_stream_is_play(substream) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
690 
691 	/* Always transfer 1 period */
692 	amount = runtime->period_size;
693 
694 	/* DMA physical address and size */
695 	dma_paddr = runtime->dma_addr + frames_to_bytes(runtime,
696 							strm->dma_buffer_pos);
697 	dma_size = frames_to_bytes(runtime, amount);
698 	desc = dmaengine_prep_slave_single(strm->dma_ch, dma_paddr, dma_size,
699 					   dir,
700 					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
701 	if (!desc) {
702 		dev_err(ssi->dev, "dmaengine_prep_slave_single() fail\n");
703 		return -ENOMEM;
704 	}
705 
706 	desc->callback = rz_ssi_dma_complete;
707 	desc->callback_param = strm;
708 
709 	if (dmaengine_submit(desc) < 0) {
710 		dev_err(ssi->dev, "dmaengine_submit() fail\n");
711 		return -EIO;
712 	}
713 
714 	/* Update DMA pointer */
715 	strm->dma_buffer_pos += amount;
716 	if (strm->dma_buffer_pos >= runtime->buffer_size)
717 		strm->dma_buffer_pos = 0;
718 
719 	/* Start DMA */
720 	dma_async_issue_pending(strm->dma_ch);
721 
722 	return 0;
723 }
724 
rz_ssi_dma_complete(void * data)725 static void rz_ssi_dma_complete(void *data)
726 {
727 	struct rz_ssi_stream *strm = (struct rz_ssi_stream *)data;
728 
729 	if (!strm->running || !strm->substream || !strm->substream->runtime)
730 		return;
731 
732 	/* Note that next DMA transaction has probably already started */
733 	rz_ssi_pointer_update(strm, strm->substream->runtime->period_size);
734 
735 	/* Queue up another DMA transaction */
736 	rz_ssi_dma_transfer(strm->priv, strm);
737 }
738 
rz_ssi_release_dma_channels(struct rz_ssi_priv * ssi)739 static void rz_ssi_release_dma_channels(struct rz_ssi_priv *ssi)
740 {
741 	if (ssi->playback.dma_ch) {
742 		dma_release_channel(ssi->playback.dma_ch);
743 		ssi->playback.dma_ch = NULL;
744 		if (ssi->dma_rt)
745 			ssi->dma_rt = false;
746 	}
747 
748 	if (ssi->capture.dma_ch) {
749 		dma_release_channel(ssi->capture.dma_ch);
750 		ssi->capture.dma_ch = NULL;
751 	}
752 }
753 
rz_ssi_dma_request(struct rz_ssi_priv * ssi,struct device * dev)754 static int rz_ssi_dma_request(struct rz_ssi_priv *ssi, struct device *dev)
755 {
756 	ssi->playback.dma_ch = dma_request_chan(dev, "tx");
757 	if (IS_ERR(ssi->playback.dma_ch))
758 		ssi->playback.dma_ch = NULL;
759 
760 	ssi->capture.dma_ch = dma_request_chan(dev, "rx");
761 	if (IS_ERR(ssi->capture.dma_ch))
762 		ssi->capture.dma_ch = NULL;
763 
764 	if (!ssi->playback.dma_ch && !ssi->capture.dma_ch) {
765 		ssi->playback.dma_ch = dma_request_chan(dev, "rt");
766 		if (IS_ERR(ssi->playback.dma_ch)) {
767 			ssi->playback.dma_ch = NULL;
768 			goto no_dma;
769 		}
770 
771 		ssi->dma_rt = true;
772 	}
773 
774 	if (!rz_ssi_is_dma_enabled(ssi))
775 		goto no_dma;
776 
777 	if (ssi->playback.dma_ch &&
778 	    (rz_ssi_dma_slave_config(ssi, ssi->playback.dma_ch, true) < 0))
779 		goto no_dma;
780 
781 	if (ssi->capture.dma_ch &&
782 	    (rz_ssi_dma_slave_config(ssi, ssi->capture.dma_ch, false) < 0))
783 		goto no_dma;
784 
785 	return 0;
786 
787 no_dma:
788 	rz_ssi_release_dma_channels(ssi);
789 
790 	return -ENODEV;
791 }
792 
rz_ssi_trigger_resume(struct rz_ssi_priv * ssi,struct rz_ssi_stream * strm)793 static int rz_ssi_trigger_resume(struct rz_ssi_priv *ssi, struct rz_ssi_stream *strm)
794 {
795 	struct snd_pcm_substream *substream = strm->substream;
796 	struct snd_pcm_runtime *runtime = substream->runtime;
797 	int ret;
798 
799 	strm->dma_buffer_pos = strm->completed_dma_buf_pos + runtime->period_size;
800 
801 	if (rz_ssi_is_stream_running(&ssi->playback) ||
802 	    rz_ssi_is_stream_running(&ssi->capture))
803 		return 0;
804 
805 	ret = rz_ssi_swreset(ssi);
806 	if (ret)
807 		return ret;
808 
809 	return rz_ssi_clk_setup(ssi, ssi->hw_params_cache.rate,
810 				ssi->hw_params_cache.channels);
811 }
812 
rz_ssi_dai_trigger(struct snd_pcm_substream * substream,int cmd,struct snd_soc_dai * dai)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, strm);
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 		break;
862 
863 	case SNDRV_PCM_TRIGGER_STOP:
864 		rz_ssi_stop(ssi, strm);
865 		rz_ssi_stream_quit(ssi, strm);
866 		break;
867 	}
868 
869 done:
870 	return ret;
871 }
872 
rz_ssi_dai_set_fmt(struct snd_soc_dai * dai,unsigned int fmt)873 static int rz_ssi_dai_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
874 {
875 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
876 
877 	switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
878 	case SND_SOC_DAIFMT_BP_FP:
879 		break;
880 	default:
881 		dev_err(ssi->dev, "Codec should be clk and frame consumer\n");
882 		return -EINVAL;
883 	}
884 
885 	/*
886 	 * set clock polarity
887 	 *
888 	 * "normal" BCLK = Signal is available at rising edge of BCLK
889 	 * "normal" FSYNC = (I2S) Left ch starts with falling FSYNC edge
890 	 */
891 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
892 	case SND_SOC_DAIFMT_NB_NF:
893 		ssi->bckp_rise = false;
894 		ssi->lrckp_fsync_fall = false;
895 		break;
896 	case SND_SOC_DAIFMT_NB_IF:
897 		ssi->bckp_rise = false;
898 		ssi->lrckp_fsync_fall = true;
899 		break;
900 	case SND_SOC_DAIFMT_IB_NF:
901 		ssi->bckp_rise = true;
902 		ssi->lrckp_fsync_fall = false;
903 		break;
904 	case SND_SOC_DAIFMT_IB_IF:
905 		ssi->bckp_rise = true;
906 		ssi->lrckp_fsync_fall = true;
907 		break;
908 	default:
909 		return -EINVAL;
910 	}
911 
912 	/* only i2s support */
913 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
914 	case SND_SOC_DAIFMT_I2S:
915 		break;
916 	default:
917 		dev_err(ssi->dev, "Only I2S mode is supported.\n");
918 		return -EINVAL;
919 	}
920 
921 	return 0;
922 }
923 
rz_ssi_startup(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)924 static int rz_ssi_startup(struct snd_pcm_substream *substream,
925 			  struct snd_soc_dai *dai)
926 {
927 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
928 
929 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
930 		ssi->dup.tx_active = true;
931 	else
932 		ssi->dup.rx_active = true;
933 
934 	return 0;
935 }
936 
rz_ssi_shutdown(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)937 static void rz_ssi_shutdown(struct snd_pcm_substream *substream,
938 			    struct snd_soc_dai *dai)
939 {
940 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
941 
942 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
943 		ssi->dup.tx_active = false;
944 	else
945 		ssi->dup.rx_active = false;
946 }
947 
rz_ssi_is_valid_hw_params(struct rz_ssi_priv * ssi,unsigned int rate,unsigned int channels,unsigned int sample_width,unsigned int sample_bits)948 static bool rz_ssi_is_valid_hw_params(struct rz_ssi_priv *ssi, unsigned int rate,
949 				      unsigned int channels,
950 				      unsigned int sample_width,
951 				      unsigned int sample_bits)
952 {
953 	if (ssi->hw_params_cache.rate != rate ||
954 	    ssi->hw_params_cache.channels != channels ||
955 	    ssi->hw_params_cache.sample_width != sample_width ||
956 	    ssi->hw_params_cache.sample_bits != sample_bits)
957 		return false;
958 
959 	return true;
960 }
961 
rz_ssi_cache_hw_params(struct rz_ssi_priv * ssi,unsigned int rate,unsigned int channels,unsigned int sample_width,unsigned int sample_bits)962 static void rz_ssi_cache_hw_params(struct rz_ssi_priv *ssi, unsigned int rate,
963 				   unsigned int channels,
964 				   unsigned int sample_width,
965 				   unsigned int sample_bits)
966 {
967 	ssi->hw_params_cache.rate = rate;
968 	ssi->hw_params_cache.channels = channels;
969 	ssi->hw_params_cache.sample_width = sample_width;
970 	ssi->hw_params_cache.sample_bits = sample_bits;
971 }
972 
rz_ssi_dai_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * dai)973 static int rz_ssi_dai_hw_params(struct snd_pcm_substream *substream,
974 				struct snd_pcm_hw_params *params,
975 				struct snd_soc_dai *dai)
976 {
977 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
978 	unsigned int sample_bits = hw_param_interval(params,
979 					SNDRV_PCM_HW_PARAM_SAMPLE_BITS)->min;
980 	unsigned int sample_width = params_width(params);
981 	unsigned int channels = params_channels(params);
982 	unsigned int rate = params_rate(params);
983 	int ret;
984 
985 	if (sample_bits != 16) {
986 		dev_err(ssi->dev, "Unsupported sample width: %d\n",
987 			sample_bits);
988 		return -EINVAL;
989 	}
990 
991 	if (channels != 2) {
992 		dev_err(ssi->dev, "Number of channels not matched: %d\n",
993 			channels);
994 		return -EINVAL;
995 	}
996 
997 	if (rz_ssi_is_stream_running(&ssi->playback) ||
998 	    rz_ssi_is_stream_running(&ssi->capture)) {
999 		if (rz_ssi_is_valid_hw_params(ssi, rate, channels, sample_width, sample_bits))
1000 			return 0;
1001 
1002 		dev_err(ssi->dev, "Full duplex needs same HW params\n");
1003 		return -EINVAL;
1004 	}
1005 
1006 	rz_ssi_cache_hw_params(ssi, rate, channels, sample_width, sample_bits);
1007 
1008 	ret = rz_ssi_swreset(ssi);
1009 	if (ret)
1010 		return ret;
1011 
1012 	return rz_ssi_clk_setup(ssi, rate, channels);
1013 }
1014 
1015 static const struct snd_soc_dai_ops rz_ssi_dai_ops = {
1016 	.startup	= rz_ssi_startup,
1017 	.shutdown	= rz_ssi_shutdown,
1018 	.trigger	= rz_ssi_dai_trigger,
1019 	.set_fmt	= rz_ssi_dai_set_fmt,
1020 	.hw_params	= rz_ssi_dai_hw_params,
1021 };
1022 
1023 static const struct snd_pcm_hardware rz_ssi_pcm_hardware = {
1024 	.info			= SNDRV_PCM_INFO_INTERLEAVED	|
1025 				  SNDRV_PCM_INFO_MMAP		|
1026 				  SNDRV_PCM_INFO_MMAP_VALID	|
1027 				  SNDRV_PCM_INFO_RESUME,
1028 	.buffer_bytes_max	= PREALLOC_BUFFER,
1029 	.period_bytes_min	= 32,
1030 	.period_bytes_max	= 8192,
1031 	.channels_min		= SSI_CHAN_MIN,
1032 	.channels_max		= SSI_CHAN_MAX,
1033 	.periods_min		= 1,
1034 	.periods_max		= 32,
1035 	.fifo_size		= 32 * 2,
1036 };
1037 
rz_ssi_pcm_open(struct snd_soc_component * component,struct snd_pcm_substream * substream)1038 static int rz_ssi_pcm_open(struct snd_soc_component *component,
1039 			   struct snd_pcm_substream *substream)
1040 {
1041 	snd_soc_set_runtime_hwparams(substream, &rz_ssi_pcm_hardware);
1042 
1043 	return snd_pcm_hw_constraint_integer(substream->runtime,
1044 					    SNDRV_PCM_HW_PARAM_PERIODS);
1045 }
1046 
rz_ssi_pcm_pointer(struct snd_soc_component * component,struct snd_pcm_substream * substream)1047 static snd_pcm_uframes_t rz_ssi_pcm_pointer(struct snd_soc_component *component,
1048 					    struct snd_pcm_substream *substream)
1049 {
1050 	struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
1051 	struct snd_soc_dai *dai = snd_soc_rtd_to_cpu(rtd, 0);
1052 	struct rz_ssi_priv *ssi = snd_soc_dai_get_drvdata(dai);
1053 	struct rz_ssi_stream *strm = rz_ssi_stream_get(ssi, substream);
1054 
1055 	return strm->buffer_pos;
1056 }
1057 
rz_ssi_pcm_new(struct snd_soc_component * component,struct snd_soc_pcm_runtime * rtd)1058 static int rz_ssi_pcm_new(struct snd_soc_component *component,
1059 			  struct snd_soc_pcm_runtime *rtd)
1060 {
1061 	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
1062 				       rtd->card->snd_card->dev,
1063 				       PREALLOC_BUFFER, PREALLOC_BUFFER_MAX);
1064 	return 0;
1065 }
1066 
1067 static struct snd_soc_dai_driver rz_ssi_soc_dai[] = {
1068 	{
1069 		.name			= "rz-ssi-dai",
1070 		.playback = {
1071 			.rates		= SSI_RATES,
1072 			.formats	= SSI_FMTS,
1073 			.channels_min	= SSI_CHAN_MIN,
1074 			.channels_max	= SSI_CHAN_MAX,
1075 		},
1076 		.capture = {
1077 			.rates		= SSI_RATES,
1078 			.formats	= SSI_FMTS,
1079 			.channels_min	= SSI_CHAN_MIN,
1080 			.channels_max	= SSI_CHAN_MAX,
1081 		},
1082 		.ops = &rz_ssi_dai_ops,
1083 	},
1084 };
1085 
1086 static const struct snd_soc_component_driver rz_ssi_soc_component = {
1087 	.name			= "rz-ssi",
1088 	.open			= rz_ssi_pcm_open,
1089 	.pointer		= rz_ssi_pcm_pointer,
1090 	.pcm_construct		= rz_ssi_pcm_new,
1091 	.legacy_dai_naming	= 1,
1092 };
1093 
rz_ssi_probe(struct platform_device * pdev)1094 static int rz_ssi_probe(struct platform_device *pdev)
1095 {
1096 	struct device *dev = &pdev->dev;
1097 	struct rz_ssi_priv *ssi;
1098 	struct clk *audio_clk;
1099 	struct resource *res;
1100 	int ret;
1101 
1102 	ssi = devm_kzalloc(dev, sizeof(*ssi), GFP_KERNEL);
1103 	if (!ssi)
1104 		return -ENOMEM;
1105 
1106 	ssi->dev = dev;
1107 	ssi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1108 	if (IS_ERR(ssi->base))
1109 		return PTR_ERR(ssi->base);
1110 
1111 	ssi->phys = res->start;
1112 	ssi->clk = devm_clk_get(dev, "ssi");
1113 	if (IS_ERR(ssi->clk))
1114 		return PTR_ERR(ssi->clk);
1115 
1116 	ssi->sfr_clk = devm_clk_get(dev, "ssi_sfr");
1117 	if (IS_ERR(ssi->sfr_clk))
1118 		return PTR_ERR(ssi->sfr_clk);
1119 
1120 	audio_clk = devm_clk_get(dev, "audio_clk1");
1121 	if (IS_ERR(audio_clk))
1122 		return dev_err_probe(&pdev->dev, PTR_ERR(audio_clk),
1123 				     "no audio clk1");
1124 
1125 	ssi->audio_clk_1 = clk_get_rate(audio_clk);
1126 	audio_clk = devm_clk_get(dev, "audio_clk2");
1127 	if (IS_ERR(audio_clk))
1128 		return dev_err_probe(&pdev->dev, PTR_ERR(audio_clk),
1129 				     "no audio clk2");
1130 
1131 	ssi->audio_clk_2 = clk_get_rate(audio_clk);
1132 	if (!(ssi->audio_clk_1 || ssi->audio_clk_2))
1133 		return dev_err_probe(&pdev->dev, -EINVAL,
1134 				     "no audio clk1 or audio clk2");
1135 
1136 	ssi->audio_mck = ssi->audio_clk_1 ? ssi->audio_clk_1 : ssi->audio_clk_2;
1137 
1138 	/* Detect DMA support */
1139 	ret = rz_ssi_dma_request(ssi, dev);
1140 	if (ret < 0) {
1141 		dev_warn(dev, "DMA not available, using PIO\n");
1142 		ssi->playback.transfer = rz_ssi_pio_send;
1143 		ssi->capture.transfer = rz_ssi_pio_recv;
1144 	} else {
1145 		dev_info(dev, "DMA enabled");
1146 		ssi->playback.transfer = rz_ssi_dma_transfer;
1147 		ssi->capture.transfer = rz_ssi_dma_transfer;
1148 	}
1149 
1150 	ssi->playback.priv = ssi;
1151 	ssi->capture.priv = ssi;
1152 
1153 	spin_lock_init(&ssi->lock);
1154 	dev_set_drvdata(dev, ssi);
1155 
1156 	/* Error Interrupt */
1157 	ssi->irq_int = platform_get_irq_byname(pdev, "int_req");
1158 	if (ssi->irq_int < 0) {
1159 		ret = ssi->irq_int;
1160 		goto err_release_dma_chs;
1161 	}
1162 
1163 	ret = devm_request_irq(dev, ssi->irq_int, &rz_ssi_interrupt,
1164 			       0, dev_name(dev), ssi);
1165 	if (ret < 0) {
1166 		dev_err_probe(dev, ret, "irq request error (int_req)\n");
1167 		goto err_release_dma_chs;
1168 	}
1169 
1170 	if (!rz_ssi_is_dma_enabled(ssi)) {
1171 		/* Tx and Rx interrupts (pio only) */
1172 		ssi->irq_tx = platform_get_irq_byname(pdev, "dma_tx");
1173 		ssi->irq_rx = platform_get_irq_byname(pdev, "dma_rx");
1174 		if (ssi->irq_tx == -ENXIO && ssi->irq_rx == -ENXIO) {
1175 			ssi->irq_rt = platform_get_irq_byname(pdev, "dma_rt");
1176 			if (ssi->irq_rt < 0)
1177 				return ssi->irq_rt;
1178 
1179 			ret = devm_request_irq(dev, ssi->irq_rt,
1180 					       &rz_ssi_interrupt, 0,
1181 					       dev_name(dev), ssi);
1182 			if (ret < 0)
1183 				return dev_err_probe(dev, ret,
1184 						     "irq request error (dma_rt)\n");
1185 		} else {
1186 			if (ssi->irq_tx < 0)
1187 				return ssi->irq_tx;
1188 
1189 			if (ssi->irq_rx < 0)
1190 				return ssi->irq_rx;
1191 
1192 			ret = devm_request_irq(dev, ssi->irq_tx,
1193 					       &rz_ssi_interrupt, 0,
1194 					       dev_name(dev), ssi);
1195 			if (ret < 0)
1196 				return dev_err_probe(dev, ret,
1197 						"irq request error (dma_tx)\n");
1198 
1199 			ret = devm_request_irq(dev, ssi->irq_rx,
1200 					       &rz_ssi_interrupt, 0,
1201 					       dev_name(dev), ssi);
1202 			if (ret < 0)
1203 				return dev_err_probe(dev, ret,
1204 						"irq request error (dma_rx)\n");
1205 		}
1206 	}
1207 
1208 	ssi->rstc = devm_reset_control_get_exclusive(dev, NULL);
1209 	if (IS_ERR(ssi->rstc)) {
1210 		ret = PTR_ERR(ssi->rstc);
1211 		goto err_release_dma_chs;
1212 	}
1213 
1214 	/* Default 0 for power saving. Can be overridden via sysfs. */
1215 	pm_runtime_set_autosuspend_delay(dev, 0);
1216 	pm_runtime_use_autosuspend(dev);
1217 	ret = devm_pm_runtime_enable(dev);
1218 	if (ret < 0) {
1219 		dev_err(dev, "Failed to enable runtime PM!\n");
1220 		goto err_release_dma_chs;
1221 	}
1222 
1223 	ret = devm_snd_soc_register_component(dev, &rz_ssi_soc_component,
1224 					      rz_ssi_soc_dai,
1225 					      ARRAY_SIZE(rz_ssi_soc_dai));
1226 	if (ret < 0) {
1227 		dev_err(dev, "failed to register snd component\n");
1228 		goto err_release_dma_chs;
1229 	}
1230 
1231 	return 0;
1232 
1233 err_release_dma_chs:
1234 	rz_ssi_release_dma_channels(ssi);
1235 
1236 	return ret;
1237 }
1238 
rz_ssi_remove(struct platform_device * pdev)1239 static void rz_ssi_remove(struct platform_device *pdev)
1240 {
1241 	struct rz_ssi_priv *ssi = dev_get_drvdata(&pdev->dev);
1242 
1243 	rz_ssi_release_dma_channels(ssi);
1244 
1245 	reset_control_assert(ssi->rstc);
1246 }
1247 
1248 static const struct of_device_id rz_ssi_of_match[] = {
1249 	{ .compatible = "renesas,rz-ssi", },
1250 	{/* Sentinel */},
1251 };
1252 MODULE_DEVICE_TABLE(of, rz_ssi_of_match);
1253 
rz_ssi_runtime_suspend(struct device * dev)1254 static int rz_ssi_runtime_suspend(struct device *dev)
1255 {
1256 	struct rz_ssi_priv *ssi = dev_get_drvdata(dev);
1257 
1258 	return reset_control_assert(ssi->rstc);
1259 }
1260 
rz_ssi_runtime_resume(struct device * dev)1261 static int rz_ssi_runtime_resume(struct device *dev)
1262 {
1263 	struct rz_ssi_priv *ssi = dev_get_drvdata(dev);
1264 
1265 	return reset_control_deassert(ssi->rstc);
1266 }
1267 
1268 static const struct dev_pm_ops rz_ssi_pm_ops = {
1269 	RUNTIME_PM_OPS(rz_ssi_runtime_suspend, rz_ssi_runtime_resume, NULL)
1270 	NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
1271 };
1272 
1273 static struct platform_driver rz_ssi_driver = {
1274 	.driver	= {
1275 		.name	= "rz-ssi-pcm-audio",
1276 		.of_match_table = rz_ssi_of_match,
1277 		.pm = pm_ptr(&rz_ssi_pm_ops),
1278 	},
1279 	.probe		= rz_ssi_probe,
1280 	.remove		= rz_ssi_remove,
1281 };
1282 
1283 module_platform_driver(rz_ssi_driver);
1284 
1285 MODULE_LICENSE("GPL v2");
1286 MODULE_DESCRIPTION("Renesas RZ/G2L ASoC Serial Sound Interface Driver");
1287 MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
1288