xref: /openbmc/linux/sound/soc/sunxi/sun4i-i2s.c (revision 8730046c)
1 /*
2  * Copyright (C) 2015 Andrea Venturi
3  * Andrea Venturi <be17068@iperbole.bo.it>
4  *
5  * Copyright (C) 2016 Maxime Ripard
6  * Maxime Ripard <maxime.ripard@free-electrons.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/dmaengine.h>
16 #include <linux/module.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/regmap.h>
20 
21 #include <sound/dmaengine_pcm.h>
22 #include <sound/pcm_params.h>
23 #include <sound/soc.h>
24 #include <sound/soc-dai.h>
25 
26 #define SUN4I_I2S_CTRL_REG		0x00
27 #define SUN4I_I2S_CTRL_SDO_EN_MASK		GENMASK(11, 8)
28 #define SUN4I_I2S_CTRL_SDO_EN(sdo)			BIT(8 + (sdo))
29 #define SUN4I_I2S_CTRL_MODE_MASK		BIT(5)
30 #define SUN4I_I2S_CTRL_MODE_SLAVE			(1 << 5)
31 #define SUN4I_I2S_CTRL_MODE_MASTER			(0 << 5)
32 #define SUN4I_I2S_CTRL_TX_EN			BIT(2)
33 #define SUN4I_I2S_CTRL_RX_EN			BIT(1)
34 #define SUN4I_I2S_CTRL_GL_EN			BIT(0)
35 
36 #define SUN4I_I2S_FMT0_REG		0x04
37 #define SUN4I_I2S_FMT0_LRCLK_POLARITY_MASK	BIT(7)
38 #define SUN4I_I2S_FMT0_LRCLK_POLARITY_INVERTED		(1 << 7)
39 #define SUN4I_I2S_FMT0_LRCLK_POLARITY_NORMAL		(0 << 7)
40 #define SUN4I_I2S_FMT0_BCLK_POLARITY_MASK	BIT(6)
41 #define SUN4I_I2S_FMT0_BCLK_POLARITY_INVERTED		(1 << 6)
42 #define SUN4I_I2S_FMT0_BCLK_POLARITY_NORMAL		(0 << 6)
43 #define SUN4I_I2S_FMT0_SR_MASK			GENMASK(5, 4)
44 #define SUN4I_I2S_FMT0_SR(sr)				((sr) << 4)
45 #define SUN4I_I2S_FMT0_WSS_MASK			GENMASK(3, 2)
46 #define SUN4I_I2S_FMT0_WSS(wss)				((wss) << 2)
47 #define SUN4I_I2S_FMT0_FMT_MASK			GENMASK(1, 0)
48 #define SUN4I_I2S_FMT0_FMT_RIGHT_J			(2 << 0)
49 #define SUN4I_I2S_FMT0_FMT_LEFT_J			(1 << 0)
50 #define SUN4I_I2S_FMT0_FMT_I2S				(0 << 0)
51 
52 #define SUN4I_I2S_FMT1_REG		0x08
53 #define SUN4I_I2S_FIFO_TX_REG		0x0c
54 #define SUN4I_I2S_FIFO_RX_REG		0x10
55 
56 #define SUN4I_I2S_FIFO_CTRL_REG		0x14
57 #define SUN4I_I2S_FIFO_CTRL_FLUSH_TX		BIT(25)
58 #define SUN4I_I2S_FIFO_CTRL_FLUSH_RX		BIT(24)
59 #define SUN4I_I2S_FIFO_CTRL_TX_MODE_MASK	BIT(2)
60 #define SUN4I_I2S_FIFO_CTRL_TX_MODE(mode)		((mode) << 2)
61 #define SUN4I_I2S_FIFO_CTRL_RX_MODE_MASK	GENMASK(1, 0)
62 #define SUN4I_I2S_FIFO_CTRL_RX_MODE(mode)		(mode)
63 
64 #define SUN4I_I2S_FIFO_STA_REG		0x18
65 
66 #define SUN4I_I2S_DMA_INT_CTRL_REG	0x1c
67 #define SUN4I_I2S_DMA_INT_CTRL_TX_DRQ_EN	BIT(7)
68 #define SUN4I_I2S_DMA_INT_CTRL_RX_DRQ_EN	BIT(3)
69 
70 #define SUN4I_I2S_INT_STA_REG		0x20
71 
72 #define SUN4I_I2S_CLK_DIV_REG		0x24
73 #define SUN4I_I2S_CLK_DIV_MCLK_EN		BIT(7)
74 #define SUN4I_I2S_CLK_DIV_BCLK_MASK		GENMASK(6, 4)
75 #define SUN4I_I2S_CLK_DIV_BCLK(bclk)			((bclk) << 4)
76 #define SUN4I_I2S_CLK_DIV_MCLK_MASK		GENMASK(3, 0)
77 #define SUN4I_I2S_CLK_DIV_MCLK(mclk)			((mclk) << 0)
78 
79 #define SUN4I_I2S_RX_CNT_REG		0x28
80 #define SUN4I_I2S_TX_CNT_REG		0x2c
81 
82 #define SUN4I_I2S_TX_CHAN_SEL_REG	0x30
83 #define SUN4I_I2S_TX_CHAN_SEL(num_chan)		(((num_chan) - 1) << 0)
84 
85 #define SUN4I_I2S_TX_CHAN_MAP_REG	0x34
86 #define SUN4I_I2S_TX_CHAN_MAP(chan, sample)	((sample) << (chan << 2))
87 
88 #define SUN4I_I2S_RX_CHAN_SEL_REG	0x38
89 #define SUN4I_I2S_RX_CHAN_MAP_REG	0x3c
90 
91 struct sun4i_i2s {
92 	struct clk	*bus_clk;
93 	struct clk	*mod_clk;
94 	struct regmap	*regmap;
95 
96 	unsigned int	mclk_freq;
97 
98 	struct snd_dmaengine_dai_dma_data	capture_dma_data;
99 	struct snd_dmaengine_dai_dma_data	playback_dma_data;
100 };
101 
102 struct sun4i_i2s_clk_div {
103 	u8	div;
104 	u8	val;
105 };
106 
107 static const struct sun4i_i2s_clk_div sun4i_i2s_bclk_div[] = {
108 	{ .div = 2, .val = 0 },
109 	{ .div = 4, .val = 1 },
110 	{ .div = 6, .val = 2 },
111 	{ .div = 8, .val = 3 },
112 	{ .div = 12, .val = 4 },
113 	{ .div = 16, .val = 5 },
114 };
115 
116 static const struct sun4i_i2s_clk_div sun4i_i2s_mclk_div[] = {
117 	{ .div = 1, .val = 0 },
118 	{ .div = 2, .val = 1 },
119 	{ .div = 4, .val = 2 },
120 	{ .div = 6, .val = 3 },
121 	{ .div = 8, .val = 4 },
122 	{ .div = 12, .val = 5 },
123 	{ .div = 16, .val = 6 },
124 	{ .div = 24, .val = 7 },
125 };
126 
127 static int sun4i_i2s_get_bclk_div(struct sun4i_i2s *i2s,
128 				  unsigned int oversample_rate,
129 				  unsigned int word_size)
130 {
131 	int div = oversample_rate / word_size / 2;
132 	int i;
133 
134 	for (i = 0; i < ARRAY_SIZE(sun4i_i2s_bclk_div); i++) {
135 		const struct sun4i_i2s_clk_div *bdiv = &sun4i_i2s_bclk_div[i];
136 
137 		if (bdiv->div == div)
138 			return bdiv->val;
139 	}
140 
141 	return -EINVAL;
142 }
143 
144 static int sun4i_i2s_get_mclk_div(struct sun4i_i2s *i2s,
145 				  unsigned int oversample_rate,
146 				  unsigned int module_rate,
147 				  unsigned int sampling_rate)
148 {
149 	int div = module_rate / sampling_rate / oversample_rate;
150 	int i;
151 
152 	for (i = 0; i < ARRAY_SIZE(sun4i_i2s_mclk_div); i++) {
153 		const struct sun4i_i2s_clk_div *mdiv = &sun4i_i2s_mclk_div[i];
154 
155 		if (mdiv->div == div)
156 			return mdiv->val;
157 	}
158 
159 	return -EINVAL;
160 }
161 
162 static int sun4i_i2s_oversample_rates[] = { 128, 192, 256, 384, 512, 768 };
163 static bool sun4i_i2s_oversample_is_valid(unsigned int oversample)
164 {
165 	int i;
166 
167 	for (i = 0; i < ARRAY_SIZE(sun4i_i2s_oversample_rates); i++)
168 		if (sun4i_i2s_oversample_rates[i] == oversample)
169 			return true;
170 
171 	return false;
172 }
173 
174 static int sun4i_i2s_set_clk_rate(struct sun4i_i2s *i2s,
175 				  unsigned int rate,
176 				  unsigned int word_size)
177 {
178 	unsigned int oversample_rate, clk_rate;
179 	int bclk_div, mclk_div;
180 	int ret;
181 
182 	switch (rate) {
183 	case 176400:
184 	case 88200:
185 	case 44100:
186 	case 22050:
187 	case 11025:
188 		clk_rate = 22579200;
189 		break;
190 
191 	case 192000:
192 	case 128000:
193 	case 96000:
194 	case 64000:
195 	case 48000:
196 	case 32000:
197 	case 24000:
198 	case 16000:
199 	case 12000:
200 	case 8000:
201 		clk_rate = 24576000;
202 		break;
203 
204 	default:
205 		return -EINVAL;
206 	}
207 
208 	ret = clk_set_rate(i2s->mod_clk, clk_rate);
209 	if (ret)
210 		return ret;
211 
212 	oversample_rate = i2s->mclk_freq / rate;
213 	if (!sun4i_i2s_oversample_is_valid(oversample_rate))
214 		return -EINVAL;
215 
216 	bclk_div = sun4i_i2s_get_bclk_div(i2s, oversample_rate,
217 					  word_size);
218 	if (bclk_div < 0)
219 		return -EINVAL;
220 
221 	mclk_div = sun4i_i2s_get_mclk_div(i2s, oversample_rate,
222 					  clk_rate, rate);
223 	if (mclk_div < 0)
224 		return -EINVAL;
225 
226 	regmap_write(i2s->regmap, SUN4I_I2S_CLK_DIV_REG,
227 		     SUN4I_I2S_CLK_DIV_BCLK(bclk_div) |
228 		     SUN4I_I2S_CLK_DIV_MCLK(mclk_div) |
229 		     SUN4I_I2S_CLK_DIV_MCLK_EN);
230 
231 	return 0;
232 }
233 
234 static int sun4i_i2s_hw_params(struct snd_pcm_substream *substream,
235 			       struct snd_pcm_hw_params *params,
236 			       struct snd_soc_dai *dai)
237 {
238 	struct sun4i_i2s *i2s = snd_soc_dai_get_drvdata(dai);
239 	int sr, wss;
240 	u32 width;
241 
242 	if (params_channels(params) != 2)
243 		return -EINVAL;
244 
245 	switch (params_physical_width(params)) {
246 	case 16:
247 		width = DMA_SLAVE_BUSWIDTH_2_BYTES;
248 		break;
249 	default:
250 		return -EINVAL;
251 	}
252 	i2s->playback_dma_data.addr_width = width;
253 
254 	switch (params_width(params)) {
255 	case 16:
256 		sr = 0;
257 		wss = 0;
258 		break;
259 
260 	default:
261 		return -EINVAL;
262 	}
263 
264 	regmap_update_bits(i2s->regmap, SUN4I_I2S_FMT0_REG,
265 			   SUN4I_I2S_FMT0_WSS_MASK | SUN4I_I2S_FMT0_SR_MASK,
266 			   SUN4I_I2S_FMT0_WSS(wss) | SUN4I_I2S_FMT0_SR(sr));
267 
268 	return sun4i_i2s_set_clk_rate(i2s, params_rate(params),
269 				      params_width(params));
270 }
271 
272 static int sun4i_i2s_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
273 {
274 	struct sun4i_i2s *i2s = snd_soc_dai_get_drvdata(dai);
275 	u32 val;
276 
277 	/* DAI Mode */
278 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
279 	case SND_SOC_DAIFMT_I2S:
280 		val = SUN4I_I2S_FMT0_FMT_I2S;
281 		break;
282 	case SND_SOC_DAIFMT_LEFT_J:
283 		val = SUN4I_I2S_FMT0_FMT_LEFT_J;
284 		break;
285 	case SND_SOC_DAIFMT_RIGHT_J:
286 		val = SUN4I_I2S_FMT0_FMT_RIGHT_J;
287 		break;
288 	default:
289 		return -EINVAL;
290 	}
291 
292 	regmap_update_bits(i2s->regmap, SUN4I_I2S_FMT0_REG,
293 			   SUN4I_I2S_FMT0_FMT_MASK,
294 			   val);
295 
296 	/* DAI clock polarity */
297 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
298 	case SND_SOC_DAIFMT_IB_IF:
299 		/* Invert both clocks */
300 		val = SUN4I_I2S_FMT0_BCLK_POLARITY_INVERTED |
301 			SUN4I_I2S_FMT0_LRCLK_POLARITY_INVERTED;
302 		break;
303 	case SND_SOC_DAIFMT_IB_NF:
304 		/* Invert bit clock */
305 		val = SUN4I_I2S_FMT0_BCLK_POLARITY_INVERTED |
306 			SUN4I_I2S_FMT0_LRCLK_POLARITY_NORMAL;
307 		break;
308 	case SND_SOC_DAIFMT_NB_IF:
309 		/* Invert frame clock */
310 		val = SUN4I_I2S_FMT0_LRCLK_POLARITY_INVERTED |
311 			SUN4I_I2S_FMT0_BCLK_POLARITY_NORMAL;
312 		break;
313 	case SND_SOC_DAIFMT_NB_NF:
314 		/* Nothing to do for both normal cases */
315 		val = SUN4I_I2S_FMT0_BCLK_POLARITY_NORMAL |
316 			SUN4I_I2S_FMT0_LRCLK_POLARITY_NORMAL;
317 		break;
318 	default:
319 		return -EINVAL;
320 	}
321 
322 	regmap_update_bits(i2s->regmap, SUN4I_I2S_FMT0_REG,
323 			   SUN4I_I2S_FMT0_BCLK_POLARITY_MASK |
324 			   SUN4I_I2S_FMT0_LRCLK_POLARITY_MASK,
325 			   val);
326 
327 	/* DAI clock master masks */
328 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
329 	case SND_SOC_DAIFMT_CBS_CFS:
330 		/* BCLK and LRCLK master */
331 		val = SUN4I_I2S_CTRL_MODE_MASTER;
332 		break;
333 	case SND_SOC_DAIFMT_CBM_CFM:
334 		/* BCLK and LRCLK slave */
335 		val = SUN4I_I2S_CTRL_MODE_SLAVE;
336 		break;
337 	default:
338 		return -EINVAL;
339 	}
340 
341 	regmap_update_bits(i2s->regmap, SUN4I_I2S_CTRL_REG,
342 			   SUN4I_I2S_CTRL_MODE_MASK,
343 			   val);
344 
345 	/* Set significant bits in our FIFOs */
346 	regmap_update_bits(i2s->regmap, SUN4I_I2S_FIFO_CTRL_REG,
347 			   SUN4I_I2S_FIFO_CTRL_TX_MODE_MASK |
348 			   SUN4I_I2S_FIFO_CTRL_RX_MODE_MASK,
349 			   SUN4I_I2S_FIFO_CTRL_TX_MODE(1) |
350 			   SUN4I_I2S_FIFO_CTRL_RX_MODE(1));
351 	return 0;
352 }
353 
354 static void sun4i_i2s_start_capture(struct sun4i_i2s *i2s)
355 {
356 	/* Flush RX FIFO */
357 	regmap_update_bits(i2s->regmap, SUN4I_I2S_FIFO_CTRL_REG,
358 			   SUN4I_I2S_FIFO_CTRL_FLUSH_RX,
359 			   SUN4I_I2S_FIFO_CTRL_FLUSH_RX);
360 
361 	/* Clear RX counter */
362 	regmap_write(i2s->regmap, SUN4I_I2S_RX_CNT_REG, 0);
363 
364 	/* Enable RX Block */
365 	regmap_update_bits(i2s->regmap, SUN4I_I2S_CTRL_REG,
366 			   SUN4I_I2S_CTRL_RX_EN,
367 			   SUN4I_I2S_CTRL_RX_EN);
368 
369 	/* Enable RX DRQ */
370 	regmap_update_bits(i2s->regmap, SUN4I_I2S_DMA_INT_CTRL_REG,
371 			   SUN4I_I2S_DMA_INT_CTRL_RX_DRQ_EN,
372 			   SUN4I_I2S_DMA_INT_CTRL_RX_DRQ_EN);
373 }
374 
375 static void sun4i_i2s_start_playback(struct sun4i_i2s *i2s)
376 {
377 	/* Flush TX FIFO */
378 	regmap_update_bits(i2s->regmap, SUN4I_I2S_FIFO_CTRL_REG,
379 			   SUN4I_I2S_FIFO_CTRL_FLUSH_TX,
380 			   SUN4I_I2S_FIFO_CTRL_FLUSH_TX);
381 
382 	/* Clear TX counter */
383 	regmap_write(i2s->regmap, SUN4I_I2S_TX_CNT_REG, 0);
384 
385 	/* Enable TX Block */
386 	regmap_update_bits(i2s->regmap, SUN4I_I2S_CTRL_REG,
387 			   SUN4I_I2S_CTRL_TX_EN,
388 			   SUN4I_I2S_CTRL_TX_EN);
389 
390 	/* Enable TX DRQ */
391 	regmap_update_bits(i2s->regmap, SUN4I_I2S_DMA_INT_CTRL_REG,
392 			   SUN4I_I2S_DMA_INT_CTRL_TX_DRQ_EN,
393 			   SUN4I_I2S_DMA_INT_CTRL_TX_DRQ_EN);
394 }
395 
396 static void sun4i_i2s_stop_capture(struct sun4i_i2s *i2s)
397 {
398 	/* Disable RX Block */
399 	regmap_update_bits(i2s->regmap, SUN4I_I2S_CTRL_REG,
400 			   SUN4I_I2S_CTRL_RX_EN,
401 			   0);
402 
403 	/* Disable RX DRQ */
404 	regmap_update_bits(i2s->regmap, SUN4I_I2S_DMA_INT_CTRL_REG,
405 			   SUN4I_I2S_DMA_INT_CTRL_RX_DRQ_EN,
406 			   0);
407 }
408 
409 static void sun4i_i2s_stop_playback(struct sun4i_i2s *i2s)
410 {
411 	/* Disable TX Block */
412 	regmap_update_bits(i2s->regmap, SUN4I_I2S_CTRL_REG,
413 			   SUN4I_I2S_CTRL_TX_EN,
414 			   0);
415 
416 	/* Disable TX DRQ */
417 	regmap_update_bits(i2s->regmap, SUN4I_I2S_DMA_INT_CTRL_REG,
418 			   SUN4I_I2S_DMA_INT_CTRL_TX_DRQ_EN,
419 			   0);
420 }
421 
422 static int sun4i_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
423 			     struct snd_soc_dai *dai)
424 {
425 	struct sun4i_i2s *i2s = snd_soc_dai_get_drvdata(dai);
426 
427 	switch (cmd) {
428 	case SNDRV_PCM_TRIGGER_START:
429 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
430 	case SNDRV_PCM_TRIGGER_RESUME:
431 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
432 			sun4i_i2s_start_playback(i2s);
433 		else
434 			sun4i_i2s_start_capture(i2s);
435 		break;
436 
437 	case SNDRV_PCM_TRIGGER_STOP:
438 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
439 	case SNDRV_PCM_TRIGGER_SUSPEND:
440 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
441 			sun4i_i2s_stop_playback(i2s);
442 		else
443 			sun4i_i2s_stop_capture(i2s);
444 		break;
445 
446 	default:
447 		return -EINVAL;
448 	}
449 
450 	return 0;
451 }
452 
453 static int sun4i_i2s_startup(struct snd_pcm_substream *substream,
454 			     struct snd_soc_dai *dai)
455 {
456 	struct sun4i_i2s *i2s = snd_soc_dai_get_drvdata(dai);
457 
458 	/* Enable the whole hardware block */
459 	regmap_write(i2s->regmap, SUN4I_I2S_CTRL_REG,
460 		     SUN4I_I2S_CTRL_GL_EN);
461 
462 	/* Enable the first output line */
463 	regmap_update_bits(i2s->regmap, SUN4I_I2S_CTRL_REG,
464 			   SUN4I_I2S_CTRL_SDO_EN_MASK,
465 			   SUN4I_I2S_CTRL_SDO_EN(0));
466 
467 	/* Enable the first two channels */
468 	regmap_write(i2s->regmap, SUN4I_I2S_TX_CHAN_SEL_REG,
469 		     SUN4I_I2S_TX_CHAN_SEL(2));
470 
471 	/* Map them to the two first samples coming in */
472 	regmap_write(i2s->regmap, SUN4I_I2S_TX_CHAN_MAP_REG,
473 		     SUN4I_I2S_TX_CHAN_MAP(0, 0) | SUN4I_I2S_TX_CHAN_MAP(1, 1));
474 
475 	return clk_prepare_enable(i2s->mod_clk);
476 }
477 
478 static void sun4i_i2s_shutdown(struct snd_pcm_substream *substream,
479 			       struct snd_soc_dai *dai)
480 {
481 	struct sun4i_i2s *i2s = snd_soc_dai_get_drvdata(dai);
482 
483 	clk_disable_unprepare(i2s->mod_clk);
484 
485 	/* Disable our output lines */
486 	regmap_update_bits(i2s->regmap, SUN4I_I2S_CTRL_REG,
487 			   SUN4I_I2S_CTRL_SDO_EN_MASK, 0);
488 
489 	/* Disable the whole hardware block */
490 	regmap_write(i2s->regmap, SUN4I_I2S_CTRL_REG, 0);
491 }
492 
493 static int sun4i_i2s_set_sysclk(struct snd_soc_dai *dai, int clk_id,
494 				unsigned int freq, int dir)
495 {
496 	struct sun4i_i2s *i2s = snd_soc_dai_get_drvdata(dai);
497 
498 	if (clk_id != 0)
499 		return -EINVAL;
500 
501 	i2s->mclk_freq = freq;
502 
503 	return 0;
504 }
505 
506 static const struct snd_soc_dai_ops sun4i_i2s_dai_ops = {
507 	.hw_params	= sun4i_i2s_hw_params,
508 	.set_fmt	= sun4i_i2s_set_fmt,
509 	.set_sysclk	= sun4i_i2s_set_sysclk,
510 	.shutdown	= sun4i_i2s_shutdown,
511 	.startup	= sun4i_i2s_startup,
512 	.trigger	= sun4i_i2s_trigger,
513 };
514 
515 static int sun4i_i2s_dai_probe(struct snd_soc_dai *dai)
516 {
517 	struct sun4i_i2s *i2s = snd_soc_dai_get_drvdata(dai);
518 
519 	snd_soc_dai_init_dma_data(dai,
520 				  &i2s->playback_dma_data,
521 				  &i2s->capture_dma_data);
522 
523 	snd_soc_dai_set_drvdata(dai, i2s);
524 
525 	return 0;
526 }
527 
528 static struct snd_soc_dai_driver sun4i_i2s_dai = {
529 	.probe = sun4i_i2s_dai_probe,
530 	.capture = {
531 		.stream_name = "Capture",
532 		.channels_min = 2,
533 		.channels_max = 2,
534 		.rates = SNDRV_PCM_RATE_8000_192000,
535 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
536 	},
537 	.playback = {
538 		.stream_name = "Playback",
539 		.channels_min = 2,
540 		.channels_max = 2,
541 		.rates = SNDRV_PCM_RATE_8000_192000,
542 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
543 	},
544 	.ops = &sun4i_i2s_dai_ops,
545 	.symmetric_rates = 1,
546 };
547 
548 static const struct snd_soc_component_driver sun4i_i2s_component = {
549 	.name	= "sun4i-dai",
550 };
551 
552 static bool sun4i_i2s_rd_reg(struct device *dev, unsigned int reg)
553 {
554 	switch (reg) {
555 	case SUN4I_I2S_FIFO_TX_REG:
556 		return false;
557 
558 	default:
559 		return true;
560 	}
561 }
562 
563 static bool sun4i_i2s_wr_reg(struct device *dev, unsigned int reg)
564 {
565 	switch (reg) {
566 	case SUN4I_I2S_FIFO_RX_REG:
567 	case SUN4I_I2S_FIFO_STA_REG:
568 		return false;
569 
570 	default:
571 		return true;
572 	}
573 }
574 
575 static bool sun4i_i2s_volatile_reg(struct device *dev, unsigned int reg)
576 {
577 	switch (reg) {
578 	case SUN4I_I2S_FIFO_RX_REG:
579 	case SUN4I_I2S_INT_STA_REG:
580 	case SUN4I_I2S_RX_CNT_REG:
581 	case SUN4I_I2S_TX_CNT_REG:
582 		return true;
583 
584 	default:
585 		return false;
586 	}
587 }
588 
589 static const struct reg_default sun4i_i2s_reg_defaults[] = {
590 	{ SUN4I_I2S_CTRL_REG, 0x00000000 },
591 	{ SUN4I_I2S_FMT0_REG, 0x0000000c },
592 	{ SUN4I_I2S_FMT1_REG, 0x00004020 },
593 	{ SUN4I_I2S_FIFO_CTRL_REG, 0x000400f0 },
594 	{ SUN4I_I2S_DMA_INT_CTRL_REG, 0x00000000 },
595 	{ SUN4I_I2S_CLK_DIV_REG, 0x00000000 },
596 	{ SUN4I_I2S_TX_CHAN_SEL_REG, 0x00000001 },
597 	{ SUN4I_I2S_TX_CHAN_MAP_REG, 0x76543210 },
598 	{ SUN4I_I2S_RX_CHAN_SEL_REG, 0x00000001 },
599 	{ SUN4I_I2S_RX_CHAN_MAP_REG, 0x00003210 },
600 };
601 
602 static const struct regmap_config sun4i_i2s_regmap_config = {
603 	.reg_bits	= 32,
604 	.reg_stride	= 4,
605 	.val_bits	= 32,
606 	.max_register	= SUN4I_I2S_RX_CHAN_MAP_REG,
607 
608 	.cache_type	= REGCACHE_FLAT,
609 	.reg_defaults	= sun4i_i2s_reg_defaults,
610 	.num_reg_defaults	= ARRAY_SIZE(sun4i_i2s_reg_defaults),
611 	.writeable_reg	= sun4i_i2s_wr_reg,
612 	.readable_reg	= sun4i_i2s_rd_reg,
613 	.volatile_reg	= sun4i_i2s_volatile_reg,
614 };
615 
616 static int sun4i_i2s_runtime_resume(struct device *dev)
617 {
618 	struct sun4i_i2s *i2s = dev_get_drvdata(dev);
619 	int ret;
620 
621 	ret = clk_prepare_enable(i2s->bus_clk);
622 	if (ret) {
623 		dev_err(dev, "Failed to enable bus clock\n");
624 		return ret;
625 	}
626 
627 	regcache_cache_only(i2s->regmap, false);
628 	regcache_mark_dirty(i2s->regmap);
629 
630 	ret = regcache_sync(i2s->regmap);
631 	if (ret) {
632 		dev_err(dev, "Failed to sync regmap cache\n");
633 		goto err_disable_clk;
634 	}
635 
636 	return 0;
637 
638 err_disable_clk:
639 	clk_disable_unprepare(i2s->bus_clk);
640 	return ret;
641 }
642 
643 static int sun4i_i2s_runtime_suspend(struct device *dev)
644 {
645 	struct sun4i_i2s *i2s = dev_get_drvdata(dev);
646 
647 	regcache_cache_only(i2s->regmap, true);
648 
649 	clk_disable_unprepare(i2s->bus_clk);
650 
651 	return 0;
652 }
653 
654 static int sun4i_i2s_probe(struct platform_device *pdev)
655 {
656 	struct sun4i_i2s *i2s;
657 	struct resource *res;
658 	void __iomem *regs;
659 	int irq, ret;
660 
661 	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
662 	if (!i2s)
663 		return -ENOMEM;
664 	platform_set_drvdata(pdev, i2s);
665 
666 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
667 	regs = devm_ioremap_resource(&pdev->dev, res);
668 	if (IS_ERR(regs))
669 		return PTR_ERR(regs);
670 
671 	irq = platform_get_irq(pdev, 0);
672 	if (irq < 0) {
673 		dev_err(&pdev->dev, "Can't retrieve our interrupt\n");
674 		return irq;
675 	}
676 
677 	i2s->bus_clk = devm_clk_get(&pdev->dev, "apb");
678 	if (IS_ERR(i2s->bus_clk)) {
679 		dev_err(&pdev->dev, "Can't get our bus clock\n");
680 		return PTR_ERR(i2s->bus_clk);
681 	}
682 
683 	i2s->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
684 					    &sun4i_i2s_regmap_config);
685 	if (IS_ERR(i2s->regmap)) {
686 		dev_err(&pdev->dev, "Regmap initialisation failed\n");
687 		return PTR_ERR(i2s->regmap);
688 	}
689 
690 	i2s->mod_clk = devm_clk_get(&pdev->dev, "mod");
691 	if (IS_ERR(i2s->mod_clk)) {
692 		dev_err(&pdev->dev, "Can't get our mod clock\n");
693 		return PTR_ERR(i2s->mod_clk);
694 	}
695 
696 	i2s->playback_dma_data.addr = res->start + SUN4I_I2S_FIFO_TX_REG;
697 	i2s->playback_dma_data.maxburst = 4;
698 
699 	i2s->capture_dma_data.addr = res->start + SUN4I_I2S_FIFO_RX_REG;
700 	i2s->capture_dma_data.maxburst = 4;
701 
702 	pm_runtime_enable(&pdev->dev);
703 	if (!pm_runtime_enabled(&pdev->dev)) {
704 		ret = sun4i_i2s_runtime_resume(&pdev->dev);
705 		if (ret)
706 			goto err_pm_disable;
707 	}
708 
709 	ret = devm_snd_soc_register_component(&pdev->dev,
710 					      &sun4i_i2s_component,
711 					      &sun4i_i2s_dai, 1);
712 	if (ret) {
713 		dev_err(&pdev->dev, "Could not register DAI\n");
714 		goto err_suspend;
715 	}
716 
717 	ret = snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
718 	if (ret) {
719 		dev_err(&pdev->dev, "Could not register PCM\n");
720 		goto err_suspend;
721 	}
722 
723 	return 0;
724 
725 err_suspend:
726 	if (!pm_runtime_status_suspended(&pdev->dev))
727 		sun4i_i2s_runtime_suspend(&pdev->dev);
728 err_pm_disable:
729 	pm_runtime_disable(&pdev->dev);
730 
731 	return ret;
732 }
733 
734 static int sun4i_i2s_remove(struct platform_device *pdev)
735 {
736 	snd_dmaengine_pcm_unregister(&pdev->dev);
737 
738 	pm_runtime_disable(&pdev->dev);
739 	if (!pm_runtime_status_suspended(&pdev->dev))
740 		sun4i_i2s_runtime_suspend(&pdev->dev);
741 
742 	return 0;
743 }
744 
745 static const struct of_device_id sun4i_i2s_match[] = {
746 	{ .compatible = "allwinner,sun4i-a10-i2s", },
747 	{}
748 };
749 MODULE_DEVICE_TABLE(of, sun4i_i2s_match);
750 
751 static const struct dev_pm_ops sun4i_i2s_pm_ops = {
752 	.runtime_resume		= sun4i_i2s_runtime_resume,
753 	.runtime_suspend	= sun4i_i2s_runtime_suspend,
754 };
755 
756 static struct platform_driver sun4i_i2s_driver = {
757 	.probe	= sun4i_i2s_probe,
758 	.remove	= sun4i_i2s_remove,
759 	.driver	= {
760 		.name		= "sun4i-i2s",
761 		.of_match_table	= sun4i_i2s_match,
762 		.pm		= &sun4i_i2s_pm_ops,
763 	},
764 };
765 module_platform_driver(sun4i_i2s_driver);
766 
767 MODULE_AUTHOR("Andrea Venturi <be17068@iperbole.bo.it>");
768 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
769 MODULE_DESCRIPTION("Allwinner A10 I2S driver");
770 MODULE_LICENSE("GPL");
771