xref: /linux/sound/soc/mxs/mxs-saif.c (revision 25aee3debe0464f6c680173041fa3de30ec9ff54)
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 <sound/saif.h>
36 #include <asm/mach-types.h>
37 #include <mach/hardware.h>
38 #include <mach/mxs.h>
39 
40 #include "mxs-saif.h"
41 
42 static struct mxs_saif *mxs_saif[2];
43 
44 /*
45  * SAIF is a little different with other normal SOC DAIs on clock using.
46  *
47  * For MXS, two SAIF modules are instantiated on-chip.
48  * Each SAIF has a set of clock pins and can be operating in master
49  * mode simultaneously if they are connected to different off-chip codecs.
50  * Also, one of the two SAIFs can master or drive the clock pins while the
51  * other SAIF, in slave mode, receives clocking from the master SAIF.
52  * This also means that both SAIFs must operate at the same sample rate.
53  *
54  * We abstract this as each saif has a master, the master could be
55  * himself or other saifs. In the generic saif driver, saif does not need
56  * to know the different clkmux. Saif only needs to know who is his master
57  * and operating his master to generate the proper clock rate for him.
58  * The master id is provided in mach-specific layer according to different
59  * clkmux setting.
60  */
61 
62 static int mxs_saif_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
63 			int clk_id, unsigned int freq, int dir)
64 {
65 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
66 
67 	switch (clk_id) {
68 	case MXS_SAIF_MCLK:
69 		saif->mclk = freq;
70 		break;
71 	default:
72 		return -EINVAL;
73 	}
74 	return 0;
75 }
76 
77 /*
78  * Since SAIF may work on EXTMASTER mode, IOW, it's working BITCLK&LRCLK
79  * is provided by other SAIF, we provide a interface here to get its master
80  * from its master_id.
81  * Note that the master could be himself.
82  */
83 static inline struct mxs_saif *mxs_saif_get_master(struct mxs_saif * saif)
84 {
85 	return mxs_saif[saif->master_id];
86 }
87 
88 /*
89  * Set SAIF clock and MCLK
90  */
91 static int mxs_saif_set_clk(struct mxs_saif *saif,
92 				  unsigned int mclk,
93 				  unsigned int rate)
94 {
95 	u32 scr;
96 	int ret;
97 	struct mxs_saif *master_saif;
98 
99 	dev_dbg(saif->dev, "mclk %d rate %d\n", mclk, rate);
100 
101 	/* Set master saif to generate proper clock */
102 	master_saif = mxs_saif_get_master(saif);
103 	if (!master_saif)
104 		return -EINVAL;
105 
106 	dev_dbg(saif->dev, "master saif%d\n", master_saif->id);
107 
108 	/* Checking if can playback and capture simutaneously */
109 	if (master_saif->ongoing && rate != master_saif->cur_rate) {
110 		dev_err(saif->dev,
111 			"can not change clock, master saif%d(rate %d) is ongoing\n",
112 			master_saif->id, master_saif->cur_rate);
113 		return -EINVAL;
114 	}
115 
116 	scr = __raw_readl(master_saif->base + SAIF_CTRL);
117 	scr &= ~BM_SAIF_CTRL_BITCLK_MULT_RATE;
118 	scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
119 
120 	/*
121 	 * Set SAIF clock
122 	 *
123 	 * The SAIF clock should be either 384*fs or 512*fs.
124 	 * If MCLK is used, the SAIF clk ratio need to match mclk ratio.
125 	 *  For 32x mclk, set saif clk as 512*fs.
126 	 *  For 48x mclk, set saif clk as 384*fs.
127 	 *
128 	 * If MCLK is not used, we just set saif clk to 512*fs.
129 	 */
130 	clk_prepare_enable(master_saif->clk);
131 
132 	if (master_saif->mclk_in_use) {
133 		if (mclk % 32 == 0) {
134 			scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
135 			ret = clk_set_rate(master_saif->clk, 512 * rate);
136 		} else if (mclk % 48 == 0) {
137 			scr |= BM_SAIF_CTRL_BITCLK_BASE_RATE;
138 			ret = clk_set_rate(master_saif->clk, 384 * rate);
139 		} else {
140 			/* SAIF MCLK should be either 32x or 48x */
141 			clk_disable_unprepare(master_saif->clk);
142 			return -EINVAL;
143 		}
144 	} else {
145 		ret = clk_set_rate(master_saif->clk, 512 * rate);
146 		scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
147 	}
148 
149 	clk_disable_unprepare(master_saif->clk);
150 
151 	if (ret)
152 		return ret;
153 
154 	master_saif->cur_rate = rate;
155 
156 	if (!master_saif->mclk_in_use) {
157 		__raw_writel(scr, master_saif->base + SAIF_CTRL);
158 		return 0;
159 	}
160 
161 	/*
162 	 * Program the over-sample rate for MCLK output
163 	 *
164 	 * The available MCLK range is 32x, 48x... 512x. The rate
165 	 * could be from 8kHz to 192kH.
166 	 */
167 	switch (mclk / rate) {
168 	case 32:
169 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(4);
170 		break;
171 	case 64:
172 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(3);
173 		break;
174 	case 128:
175 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(2);
176 		break;
177 	case 256:
178 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(1);
179 		break;
180 	case 512:
181 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(0);
182 		break;
183 	case 48:
184 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(3);
185 		break;
186 	case 96:
187 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(2);
188 		break;
189 	case 192:
190 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(1);
191 		break;
192 	case 384:
193 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(0);
194 		break;
195 	default:
196 		return -EINVAL;
197 	}
198 
199 	__raw_writel(scr, master_saif->base + SAIF_CTRL);
200 
201 	return 0;
202 }
203 
204 /*
205  * Put and disable MCLK.
206  */
207 int mxs_saif_put_mclk(unsigned int saif_id)
208 {
209 	struct mxs_saif *saif = mxs_saif[saif_id];
210 	u32 stat;
211 
212 	if (!saif)
213 		return -EINVAL;
214 
215 	stat = __raw_readl(saif->base + SAIF_STAT);
216 	if (stat & BM_SAIF_STAT_BUSY) {
217 		dev_err(saif->dev, "error: busy\n");
218 		return -EBUSY;
219 	}
220 
221 	clk_disable_unprepare(saif->clk);
222 
223 	/* disable MCLK output */
224 	__raw_writel(BM_SAIF_CTRL_CLKGATE,
225 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
226 	__raw_writel(BM_SAIF_CTRL_RUN,
227 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
228 
229 	saif->mclk_in_use = 0;
230 	return 0;
231 }
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 
286 /*
287  * SAIF DAI format configuration.
288  * Should only be called when port is inactive.
289  */
290 static int mxs_saif_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
291 {
292 	u32 scr, stat;
293 	u32 scr0;
294 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
295 
296 	stat = __raw_readl(saif->base + SAIF_STAT);
297 	if (stat & BM_SAIF_STAT_BUSY) {
298 		dev_err(cpu_dai->dev, "error: busy\n");
299 		return -EBUSY;
300 	}
301 
302 	scr0 = __raw_readl(saif->base + SAIF_CTRL);
303 	scr0 = scr0 & ~BM_SAIF_CTRL_BITCLK_EDGE & ~BM_SAIF_CTRL_LRCLK_POLARITY \
304 		& ~BM_SAIF_CTRL_JUSTIFY & ~BM_SAIF_CTRL_DELAY;
305 	scr = 0;
306 
307 	/* DAI mode */
308 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
309 	case SND_SOC_DAIFMT_I2S:
310 		/* data frame low 1clk before data */
311 		scr |= BM_SAIF_CTRL_DELAY;
312 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
313 		break;
314 	case SND_SOC_DAIFMT_LEFT_J:
315 		/* data frame high with data */
316 		scr &= ~BM_SAIF_CTRL_DELAY;
317 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
318 		scr &= ~BM_SAIF_CTRL_JUSTIFY;
319 		break;
320 	default:
321 		return -EINVAL;
322 	}
323 
324 	/* DAI clock inversion */
325 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
326 	case SND_SOC_DAIFMT_IB_IF:
327 		scr |= BM_SAIF_CTRL_BITCLK_EDGE;
328 		scr |= BM_SAIF_CTRL_LRCLK_POLARITY;
329 		break;
330 	case SND_SOC_DAIFMT_IB_NF:
331 		scr |= BM_SAIF_CTRL_BITCLK_EDGE;
332 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
333 		break;
334 	case SND_SOC_DAIFMT_NB_IF:
335 		scr &= ~BM_SAIF_CTRL_BITCLK_EDGE;
336 		scr |= BM_SAIF_CTRL_LRCLK_POLARITY;
337 		break;
338 	case SND_SOC_DAIFMT_NB_NF:
339 		scr &= ~BM_SAIF_CTRL_BITCLK_EDGE;
340 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
341 		break;
342 	}
343 
344 	/*
345 	 * Note: We simply just support master mode since SAIF TX can only
346 	 * work as master.
347 	 * Here the master is relative to codec side.
348 	 * Saif internally could be slave when working on EXTMASTER mode.
349 	 * We just hide this to machine driver.
350 	 */
351 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
352 	case SND_SOC_DAIFMT_CBS_CFS:
353 		if (saif->id == saif->master_id)
354 			scr &= ~BM_SAIF_CTRL_SLAVE_MODE;
355 		else
356 			scr |= BM_SAIF_CTRL_SLAVE_MODE;
357 
358 		__raw_writel(scr | scr0, saif->base + SAIF_CTRL);
359 		break;
360 	default:
361 		return -EINVAL;
362 	}
363 
364 	return 0;
365 }
366 
367 static int mxs_saif_startup(struct snd_pcm_substream *substream,
368 			   struct snd_soc_dai *cpu_dai)
369 {
370 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
371 	snd_soc_dai_set_dma_data(cpu_dai, substream, &saif->dma_param);
372 
373 	/* clear error status to 0 for each re-open */
374 	saif->fifo_underrun = 0;
375 	saif->fifo_overrun = 0;
376 
377 	/* Clear Reset for normal operations */
378 	__raw_writel(BM_SAIF_CTRL_SFTRST,
379 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
380 
381 	/* clear clock gate */
382 	__raw_writel(BM_SAIF_CTRL_CLKGATE,
383 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
384 
385 	return 0;
386 }
387 
388 /*
389  * Should only be called when port is inactive.
390  * although can be called multiple times by upper layers.
391  */
392 static int mxs_saif_hw_params(struct snd_pcm_substream *substream,
393 			     struct snd_pcm_hw_params *params,
394 			     struct snd_soc_dai *cpu_dai)
395 {
396 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
397 	u32 scr, stat;
398 	int ret;
399 
400 	/* mclk should already be set */
401 	if (!saif->mclk && saif->mclk_in_use) {
402 		dev_err(cpu_dai->dev, "set mclk first\n");
403 		return -EINVAL;
404 	}
405 
406 	stat = __raw_readl(saif->base + SAIF_STAT);
407 	if (stat & BM_SAIF_STAT_BUSY) {
408 		dev_err(cpu_dai->dev, "error: busy\n");
409 		return -EBUSY;
410 	}
411 
412 	/*
413 	 * Set saif clk based on sample rate.
414 	 * If mclk is used, we also set mclk, if not, saif->mclk is
415 	 * default 0, means not used.
416 	 */
417 	ret = mxs_saif_set_clk(saif, saif->mclk, params_rate(params));
418 	if (ret) {
419 		dev_err(cpu_dai->dev, "unable to get proper clk\n");
420 		return ret;
421 	}
422 
423 	scr = __raw_readl(saif->base + SAIF_CTRL);
424 
425 	scr &= ~BM_SAIF_CTRL_WORD_LENGTH;
426 	scr &= ~BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
427 	switch (params_format(params)) {
428 	case SNDRV_PCM_FORMAT_S16_LE:
429 		scr |= BF_SAIF_CTRL_WORD_LENGTH(0);
430 		break;
431 	case SNDRV_PCM_FORMAT_S20_3LE:
432 		scr |= BF_SAIF_CTRL_WORD_LENGTH(4);
433 		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
434 		break;
435 	case SNDRV_PCM_FORMAT_S24_LE:
436 		scr |= BF_SAIF_CTRL_WORD_LENGTH(8);
437 		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
438 		break;
439 	default:
440 		return -EINVAL;
441 	}
442 
443 	/* Tx/Rx config */
444 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
445 		/* enable TX mode */
446 		scr &= ~BM_SAIF_CTRL_READ_MODE;
447 	} else {
448 		/* enable RX mode */
449 		scr |= BM_SAIF_CTRL_READ_MODE;
450 	}
451 
452 	__raw_writel(scr, saif->base + SAIF_CTRL);
453 	return 0;
454 }
455 
456 static int mxs_saif_prepare(struct snd_pcm_substream *substream,
457 			   struct snd_soc_dai *cpu_dai)
458 {
459 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
460 
461 	/* enable FIFO error irqs */
462 	__raw_writel(BM_SAIF_CTRL_FIFO_ERROR_IRQ_EN,
463 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
464 
465 	return 0;
466 }
467 
468 static int mxs_saif_trigger(struct snd_pcm_substream *substream, int cmd,
469 				struct snd_soc_dai *cpu_dai)
470 {
471 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
472 	struct mxs_saif *master_saif;
473 	u32 delay;
474 
475 	master_saif = mxs_saif_get_master(saif);
476 	if (!master_saif)
477 		return -EINVAL;
478 
479 	switch (cmd) {
480 	case SNDRV_PCM_TRIGGER_START:
481 	case SNDRV_PCM_TRIGGER_RESUME:
482 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
483 		dev_dbg(cpu_dai->dev, "start\n");
484 
485 		clk_enable(master_saif->clk);
486 		if (!master_saif->mclk_in_use)
487 			__raw_writel(BM_SAIF_CTRL_RUN,
488 				master_saif->base + SAIF_CTRL + MXS_SET_ADDR);
489 
490 		/*
491 		 * If the saif's master is not himself, we also need to enable
492 		 * itself clk for its internal basic logic to work.
493 		 */
494 		if (saif != master_saif) {
495 			clk_enable(saif->clk);
496 			__raw_writel(BM_SAIF_CTRL_RUN,
497 				saif->base + SAIF_CTRL + MXS_SET_ADDR);
498 		}
499 
500 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
501 			/*
502 			 * write a data to saif data register to trigger
503 			 * the transfer
504 			 */
505 			__raw_writel(0, saif->base + SAIF_DATA);
506 		} else {
507 			/*
508 			 * read a data from saif data register to trigger
509 			 * the receive
510 			 */
511 			__raw_readl(saif->base + SAIF_DATA);
512 		}
513 
514 		master_saif->ongoing = 1;
515 
516 		dev_dbg(saif->dev, "CTRL 0x%x STAT 0x%x\n",
517 			__raw_readl(saif->base + SAIF_CTRL),
518 			__raw_readl(saif->base + SAIF_STAT));
519 
520 		dev_dbg(master_saif->dev, "CTRL 0x%x STAT 0x%x\n",
521 			__raw_readl(master_saif->base + SAIF_CTRL),
522 			__raw_readl(master_saif->base + SAIF_STAT));
523 		break;
524 	case SNDRV_PCM_TRIGGER_SUSPEND:
525 	case SNDRV_PCM_TRIGGER_STOP:
526 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
527 		dev_dbg(cpu_dai->dev, "stop\n");
528 
529 		/* wait a while for the current sample to complete */
530 		delay = USEC_PER_SEC / master_saif->cur_rate;
531 
532 		if (!master_saif->mclk_in_use) {
533 			__raw_writel(BM_SAIF_CTRL_RUN,
534 				master_saif->base + SAIF_CTRL + MXS_CLR_ADDR);
535 			udelay(delay);
536 		}
537 		clk_disable(master_saif->clk);
538 
539 		if (saif != master_saif) {
540 			__raw_writel(BM_SAIF_CTRL_RUN,
541 				saif->base + SAIF_CTRL + MXS_CLR_ADDR);
542 			udelay(delay);
543 			clk_disable(saif->clk);
544 		}
545 
546 		master_saif->ongoing = 0;
547 
548 		break;
549 	default:
550 		return -EINVAL;
551 	}
552 
553 	return 0;
554 }
555 
556 #define MXS_SAIF_RATES		SNDRV_PCM_RATE_8000_192000
557 #define MXS_SAIF_FORMATS \
558 	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
559 	SNDRV_PCM_FMTBIT_S24_LE)
560 
561 static const struct snd_soc_dai_ops mxs_saif_dai_ops = {
562 	.startup = mxs_saif_startup,
563 	.trigger = mxs_saif_trigger,
564 	.prepare = mxs_saif_prepare,
565 	.hw_params = mxs_saif_hw_params,
566 	.set_sysclk = mxs_saif_set_dai_sysclk,
567 	.set_fmt = mxs_saif_set_dai_fmt,
568 };
569 
570 static int mxs_saif_dai_probe(struct snd_soc_dai *dai)
571 {
572 	struct mxs_saif *saif = dev_get_drvdata(dai->dev);
573 
574 	snd_soc_dai_set_drvdata(dai, saif);
575 
576 	return 0;
577 }
578 
579 static struct snd_soc_dai_driver mxs_saif_dai = {
580 	.name = "mxs-saif",
581 	.probe = mxs_saif_dai_probe,
582 	.playback = {
583 		.channels_min = 2,
584 		.channels_max = 2,
585 		.rates = MXS_SAIF_RATES,
586 		.formats = MXS_SAIF_FORMATS,
587 	},
588 	.capture = {
589 		.channels_min = 2,
590 		.channels_max = 2,
591 		.rates = MXS_SAIF_RATES,
592 		.formats = MXS_SAIF_FORMATS,
593 	},
594 	.ops = &mxs_saif_dai_ops,
595 };
596 
597 static irqreturn_t mxs_saif_irq(int irq, void *dev_id)
598 {
599 	struct mxs_saif *saif = dev_id;
600 	unsigned int stat;
601 
602 	stat = __raw_readl(saif->base + SAIF_STAT);
603 	if (!(stat & (BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ |
604 			BM_SAIF_STAT_FIFO_OVERFLOW_IRQ)))
605 		return IRQ_NONE;
606 
607 	if (stat & BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ) {
608 		dev_dbg(saif->dev, "underrun!!! %d\n", ++saif->fifo_underrun);
609 		__raw_writel(BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ,
610 				saif->base + SAIF_STAT + MXS_CLR_ADDR);
611 	}
612 
613 	if (stat & BM_SAIF_STAT_FIFO_OVERFLOW_IRQ) {
614 		dev_dbg(saif->dev, "overrun!!! %d\n", ++saif->fifo_overrun);
615 		__raw_writel(BM_SAIF_STAT_FIFO_OVERFLOW_IRQ,
616 				saif->base + SAIF_STAT + MXS_CLR_ADDR);
617 	}
618 
619 	dev_dbg(saif->dev, "SAIF_CTRL %x SAIF_STAT %x\n",
620 	       __raw_readl(saif->base + SAIF_CTRL),
621 	       __raw_readl(saif->base + SAIF_STAT));
622 
623 	return IRQ_HANDLED;
624 }
625 
626 static int __devinit mxs_saif_probe(struct platform_device *pdev)
627 {
628 	struct device_node *np = pdev->dev.of_node;
629 	struct resource *iores, *dmares;
630 	struct mxs_saif *saif;
631 	struct mxs_saif_platform_data *pdata;
632 	struct pinctrl *pinctrl;
633 	int ret = 0;
634 
635 
636 	if (!np && pdev->id >= ARRAY_SIZE(mxs_saif))
637 		return -EINVAL;
638 
639 	saif = devm_kzalloc(&pdev->dev, sizeof(*saif), GFP_KERNEL);
640 	if (!saif)
641 		return -ENOMEM;
642 
643 	if (np) {
644 		struct device_node *master;
645 		saif->id = of_alias_get_id(np, "saif");
646 		if (saif->id < 0)
647 			return saif->id;
648 		/*
649 		 * If there is no "fsl,saif-master" phandle, it's a saif
650 		 * master.  Otherwise, it's a slave and its phandle points
651 		 * to the master.
652 		 */
653 		master = of_parse_phandle(np, "fsl,saif-master", 0);
654 		if (!master) {
655 			saif->master_id = saif->id;
656 		} else {
657 			saif->master_id = of_alias_get_id(master, "saif");
658 			if (saif->master_id < 0)
659 				return saif->master_id;
660 		}
661 	} else {
662 		saif->id = pdev->id;
663 		pdata = pdev->dev.platform_data;
664 		if (pdata && !pdata->master_mode)
665 			saif->master_id = pdata->master_id;
666 		else
667 			saif->master_id = saif->id;
668 	}
669 
670 	if (saif->master_id < 0 || saif->master_id >= ARRAY_SIZE(mxs_saif)) {
671 		dev_err(&pdev->dev, "get wrong master id\n");
672 		return -EINVAL;
673 	}
674 
675 	mxs_saif[saif->id] = saif;
676 
677 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
678 	if (IS_ERR(pinctrl)) {
679 		ret = PTR_ERR(pinctrl);
680 		return ret;
681 	}
682 
683 	saif->clk = clk_get(&pdev->dev, NULL);
684 	if (IS_ERR(saif->clk)) {
685 		ret = PTR_ERR(saif->clk);
686 		dev_err(&pdev->dev, "Cannot get the clock: %d\n",
687 			ret);
688 		return ret;
689 	}
690 
691 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
692 
693 	saif->base = devm_request_and_ioremap(&pdev->dev, iores);
694 	if (!saif->base) {
695 		dev_err(&pdev->dev, "ioremap failed\n");
696 		ret = -ENODEV;
697 		goto failed_get_resource;
698 	}
699 
700 	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
701 	if (!dmares) {
702 		/*
703 		 * TODO: This is a temporary solution and should be changed
704 		 * to use generic DMA binding later when the helplers get in.
705 		 */
706 		ret = of_property_read_u32(np, "fsl,saif-dma-channel",
707 					   &saif->dma_param.chan_num);
708 		if (ret) {
709 			dev_err(&pdev->dev, "failed to get dma channel\n");
710 			goto failed_get_resource;
711 		}
712 	} else {
713 		saif->dma_param.chan_num = dmares->start;
714 	}
715 
716 	saif->irq = platform_get_irq(pdev, 0);
717 	if (saif->irq < 0) {
718 		ret = saif->irq;
719 		dev_err(&pdev->dev, "failed to get irq resource: %d\n",
720 			ret);
721 		goto failed_get_resource;
722 	}
723 
724 	saif->dev = &pdev->dev;
725 	ret = devm_request_irq(&pdev->dev, saif->irq, mxs_saif_irq, 0,
726 			       "mxs-saif", saif);
727 	if (ret) {
728 		dev_err(&pdev->dev, "failed to request irq\n");
729 		goto failed_get_resource;
730 	}
731 
732 	saif->dma_param.chan_irq = platform_get_irq(pdev, 1);
733 	if (saif->dma_param.chan_irq < 0) {
734 		ret = saif->dma_param.chan_irq;
735 		dev_err(&pdev->dev, "failed to get dma irq resource: %d\n",
736 			ret);
737 		goto failed_get_resource;
738 	}
739 
740 	platform_set_drvdata(pdev, saif);
741 
742 	ret = snd_soc_register_dai(&pdev->dev, &mxs_saif_dai);
743 	if (ret) {
744 		dev_err(&pdev->dev, "register DAI failed\n");
745 		goto failed_get_resource;
746 	}
747 
748 	ret = mxs_pcm_platform_register(&pdev->dev);
749 	if (ret) {
750 		dev_err(&pdev->dev, "register PCM failed: %d\n", ret);
751 		goto failed_pdev_alloc;
752 	}
753 
754 	return 0;
755 
756 failed_pdev_alloc:
757 	snd_soc_unregister_dai(&pdev->dev);
758 failed_get_resource:
759 	clk_put(saif->clk);
760 
761 	return ret;
762 }
763 
764 static int __devexit mxs_saif_remove(struct platform_device *pdev)
765 {
766 	struct mxs_saif *saif = platform_get_drvdata(pdev);
767 
768 	mxs_pcm_platform_unregister(&pdev->dev);
769 	snd_soc_unregister_dai(&pdev->dev);
770 	clk_put(saif->clk);
771 
772 	return 0;
773 }
774 
775 static const struct of_device_id mxs_saif_dt_ids[] = {
776 	{ .compatible = "fsl,imx28-saif", },
777 	{ /* sentinel */ }
778 };
779 MODULE_DEVICE_TABLE(of, mxs_saif_dt_ids);
780 
781 static struct platform_driver mxs_saif_driver = {
782 	.probe = mxs_saif_probe,
783 	.remove = __devexit_p(mxs_saif_remove),
784 
785 	.driver = {
786 		.name = "mxs-saif",
787 		.owner = THIS_MODULE,
788 		.of_match_table = mxs_saif_dt_ids,
789 	},
790 };
791 
792 module_platform_driver(mxs_saif_driver);
793 
794 MODULE_AUTHOR("Freescale Semiconductor, Inc.");
795 MODULE_DESCRIPTION("MXS ASoC SAIF driver");
796 MODULE_LICENSE("GPL");
797