xref: /openbmc/linux/sound/soc/mxs/mxs-saif.c (revision 97da55fc)
1 /*
2  * Copyright 2011 Freescale Semiconductor, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License along
15  * with this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17  */
18 
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/of.h>
22 #include <linux/of_device.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/clk.h>
27 #include <linux/delay.h>
28 #include <linux/time.h>
29 #include <linux/fsl/mxs-dma.h>
30 #include <linux/pinctrl/consumer.h>
31 #include <sound/core.h>
32 #include <sound/pcm.h>
33 #include <sound/pcm_params.h>
34 #include <sound/soc.h>
35 #include <asm/mach-types.h>
36 #include <mach/hardware.h>
37 #include <mach/mxs.h>
38 
39 #include "mxs-saif.h"
40 
41 static struct mxs_saif *mxs_saif[2];
42 
43 /*
44  * SAIF is a little different with other normal SOC DAIs on clock using.
45  *
46  * For MXS, two SAIF modules are instantiated on-chip.
47  * Each SAIF has a set of clock pins and can be operating in master
48  * mode simultaneously if they are connected to different off-chip codecs.
49  * Also, one of the two SAIFs can master or drive the clock pins while the
50  * other SAIF, in slave mode, receives clocking from the master SAIF.
51  * This also means that both SAIFs must operate at the same sample rate.
52  *
53  * We abstract this as each saif has a master, the master could be
54  * himself or other saifs. In the generic saif driver, saif does not need
55  * to know the different clkmux. Saif only needs to know who is his master
56  * and operating his master to generate the proper clock rate for him.
57  * The master id is provided in mach-specific layer according to different
58  * clkmux setting.
59  */
60 
61 static int mxs_saif_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
62 			int clk_id, unsigned int freq, int dir)
63 {
64 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
65 
66 	switch (clk_id) {
67 	case MXS_SAIF_MCLK:
68 		saif->mclk = freq;
69 		break;
70 	default:
71 		return -EINVAL;
72 	}
73 	return 0;
74 }
75 
76 /*
77  * Since SAIF may work on EXTMASTER mode, IOW, it's working BITCLK&LRCLK
78  * is provided by other SAIF, we provide a interface here to get its master
79  * from its master_id.
80  * Note that the master could be himself.
81  */
82 static inline struct mxs_saif *mxs_saif_get_master(struct mxs_saif * saif)
83 {
84 	return mxs_saif[saif->master_id];
85 }
86 
87 /*
88  * Set SAIF clock and MCLK
89  */
90 static int mxs_saif_set_clk(struct mxs_saif *saif,
91 				  unsigned int mclk,
92 				  unsigned int rate)
93 {
94 	u32 scr;
95 	int ret;
96 	struct mxs_saif *master_saif;
97 
98 	dev_dbg(saif->dev, "mclk %d rate %d\n", mclk, rate);
99 
100 	/* Set master saif to generate proper clock */
101 	master_saif = mxs_saif_get_master(saif);
102 	if (!master_saif)
103 		return -EINVAL;
104 
105 	dev_dbg(saif->dev, "master saif%d\n", master_saif->id);
106 
107 	/* Checking if can playback and capture simutaneously */
108 	if (master_saif->ongoing && rate != master_saif->cur_rate) {
109 		dev_err(saif->dev,
110 			"can not change clock, master saif%d(rate %d) is ongoing\n",
111 			master_saif->id, master_saif->cur_rate);
112 		return -EINVAL;
113 	}
114 
115 	scr = __raw_readl(master_saif->base + SAIF_CTRL);
116 	scr &= ~BM_SAIF_CTRL_BITCLK_MULT_RATE;
117 	scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
118 
119 	/*
120 	 * Set SAIF clock
121 	 *
122 	 * The SAIF clock should be either 384*fs or 512*fs.
123 	 * If MCLK is used, the SAIF clk ratio need to match mclk ratio.
124 	 *  For 32x mclk, set saif clk as 512*fs.
125 	 *  For 48x mclk, set saif clk as 384*fs.
126 	 *
127 	 * If MCLK is not used, we just set saif clk to 512*fs.
128 	 */
129 	clk_prepare_enable(master_saif->clk);
130 
131 	if (master_saif->mclk_in_use) {
132 		if (mclk % 32 == 0) {
133 			scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
134 			ret = clk_set_rate(master_saif->clk, 512 * rate);
135 		} else if (mclk % 48 == 0) {
136 			scr |= BM_SAIF_CTRL_BITCLK_BASE_RATE;
137 			ret = clk_set_rate(master_saif->clk, 384 * rate);
138 		} else {
139 			/* SAIF MCLK should be either 32x or 48x */
140 			clk_disable_unprepare(master_saif->clk);
141 			return -EINVAL;
142 		}
143 	} else {
144 		ret = clk_set_rate(master_saif->clk, 512 * rate);
145 		scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
146 	}
147 
148 	clk_disable_unprepare(master_saif->clk);
149 
150 	if (ret)
151 		return ret;
152 
153 	master_saif->cur_rate = rate;
154 
155 	if (!master_saif->mclk_in_use) {
156 		__raw_writel(scr, master_saif->base + SAIF_CTRL);
157 		return 0;
158 	}
159 
160 	/*
161 	 * Program the over-sample rate for MCLK output
162 	 *
163 	 * The available MCLK range is 32x, 48x... 512x. The rate
164 	 * could be from 8kHz to 192kH.
165 	 */
166 	switch (mclk / rate) {
167 	case 32:
168 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(4);
169 		break;
170 	case 64:
171 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(3);
172 		break;
173 	case 128:
174 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(2);
175 		break;
176 	case 256:
177 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(1);
178 		break;
179 	case 512:
180 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(0);
181 		break;
182 	case 48:
183 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(3);
184 		break;
185 	case 96:
186 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(2);
187 		break;
188 	case 192:
189 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(1);
190 		break;
191 	case 384:
192 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(0);
193 		break;
194 	default:
195 		return -EINVAL;
196 	}
197 
198 	__raw_writel(scr, master_saif->base + SAIF_CTRL);
199 
200 	return 0;
201 }
202 
203 /*
204  * Put and disable MCLK.
205  */
206 int mxs_saif_put_mclk(unsigned int saif_id)
207 {
208 	struct mxs_saif *saif = mxs_saif[saif_id];
209 	u32 stat;
210 
211 	if (!saif)
212 		return -EINVAL;
213 
214 	stat = __raw_readl(saif->base + SAIF_STAT);
215 	if (stat & BM_SAIF_STAT_BUSY) {
216 		dev_err(saif->dev, "error: busy\n");
217 		return -EBUSY;
218 	}
219 
220 	clk_disable_unprepare(saif->clk);
221 
222 	/* disable MCLK output */
223 	__raw_writel(BM_SAIF_CTRL_CLKGATE,
224 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
225 	__raw_writel(BM_SAIF_CTRL_RUN,
226 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
227 
228 	saif->mclk_in_use = 0;
229 	return 0;
230 }
231 EXPORT_SYMBOL_GPL(mxs_saif_put_mclk);
232 
233 /*
234  * Get MCLK and set clock rate, then enable it
235  *
236  * This interface is used for codecs who are using MCLK provided
237  * by saif.
238  */
239 int mxs_saif_get_mclk(unsigned int saif_id, unsigned int mclk,
240 					unsigned int rate)
241 {
242 	struct mxs_saif *saif = mxs_saif[saif_id];
243 	u32 stat;
244 	int ret;
245 	struct mxs_saif *master_saif;
246 
247 	if (!saif)
248 		return -EINVAL;
249 
250 	/* Clear Reset */
251 	__raw_writel(BM_SAIF_CTRL_SFTRST,
252 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
253 
254 	/* FIXME: need clear clk gate for register r/w */
255 	__raw_writel(BM_SAIF_CTRL_CLKGATE,
256 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
257 
258 	master_saif = mxs_saif_get_master(saif);
259 	if (saif != master_saif) {
260 		dev_err(saif->dev, "can not get mclk from a non-master saif\n");
261 		return -EINVAL;
262 	}
263 
264 	stat = __raw_readl(saif->base + SAIF_STAT);
265 	if (stat & BM_SAIF_STAT_BUSY) {
266 		dev_err(saif->dev, "error: busy\n");
267 		return -EBUSY;
268 	}
269 
270 	saif->mclk_in_use = 1;
271 	ret = mxs_saif_set_clk(saif, mclk, rate);
272 	if (ret)
273 		return ret;
274 
275 	ret = clk_prepare_enable(saif->clk);
276 	if (ret)
277 		return ret;
278 
279 	/* enable MCLK output */
280 	__raw_writel(BM_SAIF_CTRL_RUN,
281 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
282 
283 	return 0;
284 }
285 EXPORT_SYMBOL_GPL(mxs_saif_get_mclk);
286 
287 /*
288  * SAIF DAI format configuration.
289  * Should only be called when port is inactive.
290  */
291 static int mxs_saif_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
292 {
293 	u32 scr, stat;
294 	u32 scr0;
295 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
296 
297 	stat = __raw_readl(saif->base + SAIF_STAT);
298 	if (stat & BM_SAIF_STAT_BUSY) {
299 		dev_err(cpu_dai->dev, "error: busy\n");
300 		return -EBUSY;
301 	}
302 
303 	scr0 = __raw_readl(saif->base + SAIF_CTRL);
304 	scr0 = scr0 & ~BM_SAIF_CTRL_BITCLK_EDGE & ~BM_SAIF_CTRL_LRCLK_POLARITY \
305 		& ~BM_SAIF_CTRL_JUSTIFY & ~BM_SAIF_CTRL_DELAY;
306 	scr = 0;
307 
308 	/* DAI mode */
309 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
310 	case SND_SOC_DAIFMT_I2S:
311 		/* data frame low 1clk before data */
312 		scr |= BM_SAIF_CTRL_DELAY;
313 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
314 		break;
315 	case SND_SOC_DAIFMT_LEFT_J:
316 		/* data frame high with data */
317 		scr &= ~BM_SAIF_CTRL_DELAY;
318 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
319 		scr &= ~BM_SAIF_CTRL_JUSTIFY;
320 		break;
321 	default:
322 		return -EINVAL;
323 	}
324 
325 	/* DAI clock inversion */
326 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
327 	case SND_SOC_DAIFMT_IB_IF:
328 		scr |= BM_SAIF_CTRL_BITCLK_EDGE;
329 		scr |= BM_SAIF_CTRL_LRCLK_POLARITY;
330 		break;
331 	case SND_SOC_DAIFMT_IB_NF:
332 		scr |= BM_SAIF_CTRL_BITCLK_EDGE;
333 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
334 		break;
335 	case SND_SOC_DAIFMT_NB_IF:
336 		scr &= ~BM_SAIF_CTRL_BITCLK_EDGE;
337 		scr |= BM_SAIF_CTRL_LRCLK_POLARITY;
338 		break;
339 	case SND_SOC_DAIFMT_NB_NF:
340 		scr &= ~BM_SAIF_CTRL_BITCLK_EDGE;
341 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
342 		break;
343 	}
344 
345 	/*
346 	 * Note: We simply just support master mode since SAIF TX can only
347 	 * work as master.
348 	 * Here the master is relative to codec side.
349 	 * Saif internally could be slave when working on EXTMASTER mode.
350 	 * We just hide this to machine driver.
351 	 */
352 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
353 	case SND_SOC_DAIFMT_CBS_CFS:
354 		if (saif->id == saif->master_id)
355 			scr &= ~BM_SAIF_CTRL_SLAVE_MODE;
356 		else
357 			scr |= BM_SAIF_CTRL_SLAVE_MODE;
358 
359 		__raw_writel(scr | scr0, saif->base + SAIF_CTRL);
360 		break;
361 	default:
362 		return -EINVAL;
363 	}
364 
365 	return 0;
366 }
367 
368 static int mxs_saif_startup(struct snd_pcm_substream *substream,
369 			   struct snd_soc_dai *cpu_dai)
370 {
371 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
372 	snd_soc_dai_set_dma_data(cpu_dai, substream, &saif->dma_param);
373 
374 	/* clear error status to 0 for each re-open */
375 	saif->fifo_underrun = 0;
376 	saif->fifo_overrun = 0;
377 
378 	/* Clear Reset for normal operations */
379 	__raw_writel(BM_SAIF_CTRL_SFTRST,
380 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
381 
382 	/* clear clock gate */
383 	__raw_writel(BM_SAIF_CTRL_CLKGATE,
384 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
385 
386 	return 0;
387 }
388 
389 /*
390  * Should only be called when port is inactive.
391  * although can be called multiple times by upper layers.
392  */
393 static int mxs_saif_hw_params(struct snd_pcm_substream *substream,
394 			     struct snd_pcm_hw_params *params,
395 			     struct snd_soc_dai *cpu_dai)
396 {
397 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
398 	struct mxs_saif *master_saif;
399 	u32 scr, stat;
400 	int ret;
401 
402 	master_saif = mxs_saif_get_master(saif);
403 	if (!master_saif)
404 		return -EINVAL;
405 
406 	/* mclk should already be set */
407 	if (!saif->mclk && saif->mclk_in_use) {
408 		dev_err(cpu_dai->dev, "set mclk first\n");
409 		return -EINVAL;
410 	}
411 
412 	stat = __raw_readl(saif->base + SAIF_STAT);
413 	if (stat & BM_SAIF_STAT_BUSY) {
414 		dev_err(cpu_dai->dev, "error: busy\n");
415 		return -EBUSY;
416 	}
417 
418 	/*
419 	 * Set saif clk based on sample rate.
420 	 * If mclk is used, we also set mclk, if not, saif->mclk is
421 	 * default 0, means not used.
422 	 */
423 	ret = mxs_saif_set_clk(saif, saif->mclk, params_rate(params));
424 	if (ret) {
425 		dev_err(cpu_dai->dev, "unable to get proper clk\n");
426 		return ret;
427 	}
428 
429 	/* prepare clk in hw_param, enable in trigger */
430 	clk_prepare(saif->clk);
431 	if (saif != master_saif) {
432 		/*
433 		* Set an initial clock rate for the saif internal logic to work
434 		* properly. This is important when working in EXTMASTER mode
435 		* that uses the other saif's BITCLK&LRCLK but it still needs a
436 		* basic clock which should be fast enough for the internal
437 		* logic.
438 		*/
439 		clk_enable(saif->clk);
440 		ret = clk_set_rate(saif->clk, 24000000);
441 		clk_disable(saif->clk);
442 		if (ret)
443 			return ret;
444 
445 		clk_prepare(master_saif->clk);
446 	}
447 
448 	scr = __raw_readl(saif->base + SAIF_CTRL);
449 
450 	scr &= ~BM_SAIF_CTRL_WORD_LENGTH;
451 	scr &= ~BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
452 	switch (params_format(params)) {
453 	case SNDRV_PCM_FORMAT_S16_LE:
454 		scr |= BF_SAIF_CTRL_WORD_LENGTH(0);
455 		break;
456 	case SNDRV_PCM_FORMAT_S20_3LE:
457 		scr |= BF_SAIF_CTRL_WORD_LENGTH(4);
458 		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
459 		break;
460 	case SNDRV_PCM_FORMAT_S24_LE:
461 		scr |= BF_SAIF_CTRL_WORD_LENGTH(8);
462 		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
463 		break;
464 	default:
465 		return -EINVAL;
466 	}
467 
468 	/* Tx/Rx config */
469 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
470 		/* enable TX mode */
471 		scr &= ~BM_SAIF_CTRL_READ_MODE;
472 	} else {
473 		/* enable RX mode */
474 		scr |= BM_SAIF_CTRL_READ_MODE;
475 	}
476 
477 	__raw_writel(scr, saif->base + SAIF_CTRL);
478 	return 0;
479 }
480 
481 static int mxs_saif_prepare(struct snd_pcm_substream *substream,
482 			   struct snd_soc_dai *cpu_dai)
483 {
484 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
485 
486 	/* enable FIFO error irqs */
487 	__raw_writel(BM_SAIF_CTRL_FIFO_ERROR_IRQ_EN,
488 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
489 
490 	return 0;
491 }
492 
493 static int mxs_saif_trigger(struct snd_pcm_substream *substream, int cmd,
494 				struct snd_soc_dai *cpu_dai)
495 {
496 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
497 	struct mxs_saif *master_saif;
498 	u32 delay;
499 
500 	master_saif = mxs_saif_get_master(saif);
501 	if (!master_saif)
502 		return -EINVAL;
503 
504 	switch (cmd) {
505 	case SNDRV_PCM_TRIGGER_START:
506 	case SNDRV_PCM_TRIGGER_RESUME:
507 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
508 		dev_dbg(cpu_dai->dev, "start\n");
509 
510 		clk_enable(master_saif->clk);
511 		if (!master_saif->mclk_in_use)
512 			__raw_writel(BM_SAIF_CTRL_RUN,
513 				master_saif->base + SAIF_CTRL + MXS_SET_ADDR);
514 
515 		/*
516 		 * If the saif's master is not himself, we also need to enable
517 		 * itself clk for its internal basic logic to work.
518 		 */
519 		if (saif != master_saif) {
520 			clk_enable(saif->clk);
521 			__raw_writel(BM_SAIF_CTRL_RUN,
522 				saif->base + SAIF_CTRL + MXS_SET_ADDR);
523 		}
524 
525 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
526 			/*
527 			 * write data to saif data register to trigger
528 			 * the transfer.
529 			 * For 24-bit format the 32-bit FIFO register stores
530 			 * only one channel, so we need to write twice.
531 			 * This is also safe for the other non 24-bit formats.
532 			 */
533 			__raw_writel(0, saif->base + SAIF_DATA);
534 			__raw_writel(0, saif->base + SAIF_DATA);
535 		} else {
536 			/*
537 			 * read data from saif data register to trigger
538 			 * the receive.
539 			 * For 24-bit format the 32-bit FIFO register stores
540 			 * only one channel, so we need to read twice.
541 			 * This is also safe for the other non 24-bit formats.
542 			 */
543 			__raw_readl(saif->base + SAIF_DATA);
544 			__raw_readl(saif->base + SAIF_DATA);
545 		}
546 
547 		master_saif->ongoing = 1;
548 
549 		dev_dbg(saif->dev, "CTRL 0x%x STAT 0x%x\n",
550 			__raw_readl(saif->base + SAIF_CTRL),
551 			__raw_readl(saif->base + SAIF_STAT));
552 
553 		dev_dbg(master_saif->dev, "CTRL 0x%x STAT 0x%x\n",
554 			__raw_readl(master_saif->base + SAIF_CTRL),
555 			__raw_readl(master_saif->base + SAIF_STAT));
556 		break;
557 	case SNDRV_PCM_TRIGGER_SUSPEND:
558 	case SNDRV_PCM_TRIGGER_STOP:
559 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
560 		dev_dbg(cpu_dai->dev, "stop\n");
561 
562 		/* wait a while for the current sample to complete */
563 		delay = USEC_PER_SEC / master_saif->cur_rate;
564 
565 		if (!master_saif->mclk_in_use) {
566 			__raw_writel(BM_SAIF_CTRL_RUN,
567 				master_saif->base + SAIF_CTRL + MXS_CLR_ADDR);
568 			udelay(delay);
569 		}
570 		clk_disable(master_saif->clk);
571 
572 		if (saif != master_saif) {
573 			__raw_writel(BM_SAIF_CTRL_RUN,
574 				saif->base + SAIF_CTRL + MXS_CLR_ADDR);
575 			udelay(delay);
576 			clk_disable(saif->clk);
577 		}
578 
579 		master_saif->ongoing = 0;
580 
581 		break;
582 	default:
583 		return -EINVAL;
584 	}
585 
586 	return 0;
587 }
588 
589 #define MXS_SAIF_RATES		SNDRV_PCM_RATE_8000_192000
590 #define MXS_SAIF_FORMATS \
591 	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
592 	SNDRV_PCM_FMTBIT_S24_LE)
593 
594 static const struct snd_soc_dai_ops mxs_saif_dai_ops = {
595 	.startup = mxs_saif_startup,
596 	.trigger = mxs_saif_trigger,
597 	.prepare = mxs_saif_prepare,
598 	.hw_params = mxs_saif_hw_params,
599 	.set_sysclk = mxs_saif_set_dai_sysclk,
600 	.set_fmt = mxs_saif_set_dai_fmt,
601 };
602 
603 static int mxs_saif_dai_probe(struct snd_soc_dai *dai)
604 {
605 	struct mxs_saif *saif = dev_get_drvdata(dai->dev);
606 
607 	snd_soc_dai_set_drvdata(dai, saif);
608 
609 	return 0;
610 }
611 
612 static struct snd_soc_dai_driver mxs_saif_dai = {
613 	.name = "mxs-saif",
614 	.probe = mxs_saif_dai_probe,
615 	.playback = {
616 		.channels_min = 2,
617 		.channels_max = 2,
618 		.rates = MXS_SAIF_RATES,
619 		.formats = MXS_SAIF_FORMATS,
620 	},
621 	.capture = {
622 		.channels_min = 2,
623 		.channels_max = 2,
624 		.rates = MXS_SAIF_RATES,
625 		.formats = MXS_SAIF_FORMATS,
626 	},
627 	.ops = &mxs_saif_dai_ops,
628 };
629 
630 static irqreturn_t mxs_saif_irq(int irq, void *dev_id)
631 {
632 	struct mxs_saif *saif = dev_id;
633 	unsigned int stat;
634 
635 	stat = __raw_readl(saif->base + SAIF_STAT);
636 	if (!(stat & (BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ |
637 			BM_SAIF_STAT_FIFO_OVERFLOW_IRQ)))
638 		return IRQ_NONE;
639 
640 	if (stat & BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ) {
641 		dev_dbg(saif->dev, "underrun!!! %d\n", ++saif->fifo_underrun);
642 		__raw_writel(BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ,
643 				saif->base + SAIF_STAT + MXS_CLR_ADDR);
644 	}
645 
646 	if (stat & BM_SAIF_STAT_FIFO_OVERFLOW_IRQ) {
647 		dev_dbg(saif->dev, "overrun!!! %d\n", ++saif->fifo_overrun);
648 		__raw_writel(BM_SAIF_STAT_FIFO_OVERFLOW_IRQ,
649 				saif->base + SAIF_STAT + MXS_CLR_ADDR);
650 	}
651 
652 	dev_dbg(saif->dev, "SAIF_CTRL %x SAIF_STAT %x\n",
653 	       __raw_readl(saif->base + SAIF_CTRL),
654 	       __raw_readl(saif->base + SAIF_STAT));
655 
656 	return IRQ_HANDLED;
657 }
658 
659 static int mxs_saif_probe(struct platform_device *pdev)
660 {
661 	struct device_node *np = pdev->dev.of_node;
662 	struct resource *iores, *dmares;
663 	struct mxs_saif *saif;
664 	struct pinctrl *pinctrl;
665 	int ret = 0;
666 	struct device_node *master;
667 
668 	if (!np)
669 		return -EINVAL;
670 
671 	saif = devm_kzalloc(&pdev->dev, sizeof(*saif), GFP_KERNEL);
672 	if (!saif)
673 		return -ENOMEM;
674 
675 	ret = of_alias_get_id(np, "saif");
676 	if (ret < 0)
677 		return ret;
678 	else
679 		saif->id = ret;
680 
681 	/*
682 	 * If there is no "fsl,saif-master" phandle, it's a saif
683 	 * master.  Otherwise, it's a slave and its phandle points
684 	 * to the master.
685 	 */
686 	master = of_parse_phandle(np, "fsl,saif-master", 0);
687 	if (!master) {
688 		saif->master_id = saif->id;
689 	} else {
690 		ret = of_alias_get_id(master, "saif");
691 		if (ret < 0)
692 			return ret;
693 		else
694 			saif->master_id = ret;
695 	}
696 
697 	if (saif->master_id >= ARRAY_SIZE(mxs_saif)) {
698 		dev_err(&pdev->dev, "get wrong master id\n");
699 		return -EINVAL;
700 	}
701 
702 	mxs_saif[saif->id] = saif;
703 
704 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
705 	if (IS_ERR(pinctrl)) {
706 		ret = PTR_ERR(pinctrl);
707 		return ret;
708 	}
709 
710 	saif->clk = devm_clk_get(&pdev->dev, NULL);
711 	if (IS_ERR(saif->clk)) {
712 		ret = PTR_ERR(saif->clk);
713 		dev_err(&pdev->dev, "Cannot get the clock: %d\n",
714 			ret);
715 		return ret;
716 	}
717 
718 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
719 
720 	saif->base = devm_ioremap_resource(&pdev->dev, iores);
721 	if (IS_ERR(saif->base))
722 		return PTR_ERR(saif->base);
723 
724 	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
725 	if (!dmares) {
726 		/*
727 		 * TODO: This is a temporary solution and should be changed
728 		 * to use generic DMA binding later when the helplers get in.
729 		 */
730 		ret = of_property_read_u32(np, "fsl,saif-dma-channel",
731 					   &saif->dma_param.chan_num);
732 		if (ret) {
733 			dev_err(&pdev->dev, "failed to get dma channel\n");
734 			return ret;
735 		}
736 	} else {
737 		saif->dma_param.chan_num = dmares->start;
738 	}
739 
740 	saif->irq = platform_get_irq(pdev, 0);
741 	if (saif->irq < 0) {
742 		ret = saif->irq;
743 		dev_err(&pdev->dev, "failed to get irq resource: %d\n",
744 			ret);
745 		return ret;
746 	}
747 
748 	saif->dev = &pdev->dev;
749 	ret = devm_request_irq(&pdev->dev, saif->irq, mxs_saif_irq, 0,
750 			       "mxs-saif", saif);
751 	if (ret) {
752 		dev_err(&pdev->dev, "failed to request irq\n");
753 		return ret;
754 	}
755 
756 	saif->dma_param.chan_irq = platform_get_irq(pdev, 1);
757 	if (saif->dma_param.chan_irq < 0) {
758 		ret = saif->dma_param.chan_irq;
759 		dev_err(&pdev->dev, "failed to get dma irq resource: %d\n",
760 			ret);
761 		return ret;
762 	}
763 
764 	platform_set_drvdata(pdev, saif);
765 
766 	ret = snd_soc_register_dai(&pdev->dev, &mxs_saif_dai);
767 	if (ret) {
768 		dev_err(&pdev->dev, "register DAI failed\n");
769 		return ret;
770 	}
771 
772 	ret = mxs_pcm_platform_register(&pdev->dev);
773 	if (ret) {
774 		dev_err(&pdev->dev, "register PCM failed: %d\n", ret);
775 		goto failed_pdev_alloc;
776 	}
777 
778 	return 0;
779 
780 failed_pdev_alloc:
781 	snd_soc_unregister_dai(&pdev->dev);
782 
783 	return ret;
784 }
785 
786 static int mxs_saif_remove(struct platform_device *pdev)
787 {
788 	mxs_pcm_platform_unregister(&pdev->dev);
789 	snd_soc_unregister_dai(&pdev->dev);
790 
791 	return 0;
792 }
793 
794 static const struct of_device_id mxs_saif_dt_ids[] = {
795 	{ .compatible = "fsl,imx28-saif", },
796 	{ /* sentinel */ }
797 };
798 MODULE_DEVICE_TABLE(of, mxs_saif_dt_ids);
799 
800 static struct platform_driver mxs_saif_driver = {
801 	.probe = mxs_saif_probe,
802 	.remove = mxs_saif_remove,
803 
804 	.driver = {
805 		.name = "mxs-saif",
806 		.owner = THIS_MODULE,
807 		.of_match_table = mxs_saif_dt_ids,
808 	},
809 };
810 
811 module_platform_driver(mxs_saif_driver);
812 
813 MODULE_AUTHOR("Freescale Semiconductor, Inc.");
814 MODULE_DESCRIPTION("MXS ASoC SAIF driver");
815 MODULE_LICENSE("GPL");
816 MODULE_ALIAS("platform:mxs-saif");
817