xref: /openbmc/linux/sound/soc/mxs/mxs-saif.c (revision 95e9fd10)
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 	struct mxs_saif *master_saif;
398 	u32 scr, stat;
399 	int ret;
400 
401 	master_saif = mxs_saif_get_master(saif);
402 	if (!master_saif)
403 		return -EINVAL;
404 
405 	/* mclk should already be set */
406 	if (!saif->mclk && saif->mclk_in_use) {
407 		dev_err(cpu_dai->dev, "set mclk first\n");
408 		return -EINVAL;
409 	}
410 
411 	stat = __raw_readl(saif->base + SAIF_STAT);
412 	if (stat & BM_SAIF_STAT_BUSY) {
413 		dev_err(cpu_dai->dev, "error: busy\n");
414 		return -EBUSY;
415 	}
416 
417 	/*
418 	 * Set saif clk based on sample rate.
419 	 * If mclk is used, we also set mclk, if not, saif->mclk is
420 	 * default 0, means not used.
421 	 */
422 	ret = mxs_saif_set_clk(saif, saif->mclk, params_rate(params));
423 	if (ret) {
424 		dev_err(cpu_dai->dev, "unable to get proper clk\n");
425 		return ret;
426 	}
427 
428 	/* prepare clk in hw_param, enable in trigger */
429 	clk_prepare(saif->clk);
430 	if (saif != master_saif) {
431 		/*
432 		* Set an initial clock rate for the saif internal logic to work
433 		* properly. This is important when working in EXTMASTER mode
434 		* that uses the other saif's BITCLK&LRCLK but it still needs a
435 		* basic clock which should be fast enough for the internal
436 		* logic.
437 		*/
438 		clk_enable(saif->clk);
439 		ret = clk_set_rate(saif->clk, 24000000);
440 		clk_disable(saif->clk);
441 		if (ret)
442 			return ret;
443 
444 		clk_prepare(master_saif->clk);
445 	}
446 
447 	scr = __raw_readl(saif->base + SAIF_CTRL);
448 
449 	scr &= ~BM_SAIF_CTRL_WORD_LENGTH;
450 	scr &= ~BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
451 	switch (params_format(params)) {
452 	case SNDRV_PCM_FORMAT_S16_LE:
453 		scr |= BF_SAIF_CTRL_WORD_LENGTH(0);
454 		break;
455 	case SNDRV_PCM_FORMAT_S20_3LE:
456 		scr |= BF_SAIF_CTRL_WORD_LENGTH(4);
457 		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
458 		break;
459 	case SNDRV_PCM_FORMAT_S24_LE:
460 		scr |= BF_SAIF_CTRL_WORD_LENGTH(8);
461 		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
462 		break;
463 	default:
464 		return -EINVAL;
465 	}
466 
467 	/* Tx/Rx config */
468 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
469 		/* enable TX mode */
470 		scr &= ~BM_SAIF_CTRL_READ_MODE;
471 	} else {
472 		/* enable RX mode */
473 		scr |= BM_SAIF_CTRL_READ_MODE;
474 	}
475 
476 	__raw_writel(scr, saif->base + SAIF_CTRL);
477 	return 0;
478 }
479 
480 static int mxs_saif_prepare(struct snd_pcm_substream *substream,
481 			   struct snd_soc_dai *cpu_dai)
482 {
483 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
484 
485 	/* enable FIFO error irqs */
486 	__raw_writel(BM_SAIF_CTRL_FIFO_ERROR_IRQ_EN,
487 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
488 
489 	return 0;
490 }
491 
492 static int mxs_saif_trigger(struct snd_pcm_substream *substream, int cmd,
493 				struct snd_soc_dai *cpu_dai)
494 {
495 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
496 	struct mxs_saif *master_saif;
497 	u32 delay;
498 
499 	master_saif = mxs_saif_get_master(saif);
500 	if (!master_saif)
501 		return -EINVAL;
502 
503 	switch (cmd) {
504 	case SNDRV_PCM_TRIGGER_START:
505 	case SNDRV_PCM_TRIGGER_RESUME:
506 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
507 		dev_dbg(cpu_dai->dev, "start\n");
508 
509 		clk_enable(master_saif->clk);
510 		if (!master_saif->mclk_in_use)
511 			__raw_writel(BM_SAIF_CTRL_RUN,
512 				master_saif->base + SAIF_CTRL + MXS_SET_ADDR);
513 
514 		/*
515 		 * If the saif's master is not himself, we also need to enable
516 		 * itself clk for its internal basic logic to work.
517 		 */
518 		if (saif != master_saif) {
519 			clk_enable(saif->clk);
520 			__raw_writel(BM_SAIF_CTRL_RUN,
521 				saif->base + SAIF_CTRL + MXS_SET_ADDR);
522 		}
523 
524 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
525 			/*
526 			 * write a data to saif data register to trigger
527 			 * the transfer
528 			 */
529 			__raw_writel(0, saif->base + SAIF_DATA);
530 		} else {
531 			/*
532 			 * read a data from saif data register to trigger
533 			 * the receive
534 			 */
535 			__raw_readl(saif->base + SAIF_DATA);
536 		}
537 
538 		master_saif->ongoing = 1;
539 
540 		dev_dbg(saif->dev, "CTRL 0x%x STAT 0x%x\n",
541 			__raw_readl(saif->base + SAIF_CTRL),
542 			__raw_readl(saif->base + SAIF_STAT));
543 
544 		dev_dbg(master_saif->dev, "CTRL 0x%x STAT 0x%x\n",
545 			__raw_readl(master_saif->base + SAIF_CTRL),
546 			__raw_readl(master_saif->base + SAIF_STAT));
547 		break;
548 	case SNDRV_PCM_TRIGGER_SUSPEND:
549 	case SNDRV_PCM_TRIGGER_STOP:
550 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
551 		dev_dbg(cpu_dai->dev, "stop\n");
552 
553 		/* wait a while for the current sample to complete */
554 		delay = USEC_PER_SEC / master_saif->cur_rate;
555 
556 		if (!master_saif->mclk_in_use) {
557 			__raw_writel(BM_SAIF_CTRL_RUN,
558 				master_saif->base + SAIF_CTRL + MXS_CLR_ADDR);
559 			udelay(delay);
560 		}
561 		clk_disable(master_saif->clk);
562 
563 		if (saif != master_saif) {
564 			__raw_writel(BM_SAIF_CTRL_RUN,
565 				saif->base + SAIF_CTRL + MXS_CLR_ADDR);
566 			udelay(delay);
567 			clk_disable(saif->clk);
568 		}
569 
570 		master_saif->ongoing = 0;
571 
572 		break;
573 	default:
574 		return -EINVAL;
575 	}
576 
577 	return 0;
578 }
579 
580 #define MXS_SAIF_RATES		SNDRV_PCM_RATE_8000_192000
581 #define MXS_SAIF_FORMATS \
582 	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
583 	SNDRV_PCM_FMTBIT_S24_LE)
584 
585 static const struct snd_soc_dai_ops mxs_saif_dai_ops = {
586 	.startup = mxs_saif_startup,
587 	.trigger = mxs_saif_trigger,
588 	.prepare = mxs_saif_prepare,
589 	.hw_params = mxs_saif_hw_params,
590 	.set_sysclk = mxs_saif_set_dai_sysclk,
591 	.set_fmt = mxs_saif_set_dai_fmt,
592 };
593 
594 static int mxs_saif_dai_probe(struct snd_soc_dai *dai)
595 {
596 	struct mxs_saif *saif = dev_get_drvdata(dai->dev);
597 
598 	snd_soc_dai_set_drvdata(dai, saif);
599 
600 	return 0;
601 }
602 
603 static struct snd_soc_dai_driver mxs_saif_dai = {
604 	.name = "mxs-saif",
605 	.probe = mxs_saif_dai_probe,
606 	.playback = {
607 		.channels_min = 2,
608 		.channels_max = 2,
609 		.rates = MXS_SAIF_RATES,
610 		.formats = MXS_SAIF_FORMATS,
611 	},
612 	.capture = {
613 		.channels_min = 2,
614 		.channels_max = 2,
615 		.rates = MXS_SAIF_RATES,
616 		.formats = MXS_SAIF_FORMATS,
617 	},
618 	.ops = &mxs_saif_dai_ops,
619 };
620 
621 static irqreturn_t mxs_saif_irq(int irq, void *dev_id)
622 {
623 	struct mxs_saif *saif = dev_id;
624 	unsigned int stat;
625 
626 	stat = __raw_readl(saif->base + SAIF_STAT);
627 	if (!(stat & (BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ |
628 			BM_SAIF_STAT_FIFO_OVERFLOW_IRQ)))
629 		return IRQ_NONE;
630 
631 	if (stat & BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ) {
632 		dev_dbg(saif->dev, "underrun!!! %d\n", ++saif->fifo_underrun);
633 		__raw_writel(BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ,
634 				saif->base + SAIF_STAT + MXS_CLR_ADDR);
635 	}
636 
637 	if (stat & BM_SAIF_STAT_FIFO_OVERFLOW_IRQ) {
638 		dev_dbg(saif->dev, "overrun!!! %d\n", ++saif->fifo_overrun);
639 		__raw_writel(BM_SAIF_STAT_FIFO_OVERFLOW_IRQ,
640 				saif->base + SAIF_STAT + MXS_CLR_ADDR);
641 	}
642 
643 	dev_dbg(saif->dev, "SAIF_CTRL %x SAIF_STAT %x\n",
644 	       __raw_readl(saif->base + SAIF_CTRL),
645 	       __raw_readl(saif->base + SAIF_STAT));
646 
647 	return IRQ_HANDLED;
648 }
649 
650 static int __devinit mxs_saif_probe(struct platform_device *pdev)
651 {
652 	struct device_node *np = pdev->dev.of_node;
653 	struct resource *iores, *dmares;
654 	struct mxs_saif *saif;
655 	struct mxs_saif_platform_data *pdata;
656 	struct pinctrl *pinctrl;
657 	int ret = 0;
658 
659 
660 	if (!np && pdev->id >= ARRAY_SIZE(mxs_saif))
661 		return -EINVAL;
662 
663 	saif = devm_kzalloc(&pdev->dev, sizeof(*saif), GFP_KERNEL);
664 	if (!saif)
665 		return -ENOMEM;
666 
667 	if (np) {
668 		struct device_node *master;
669 		saif->id = of_alias_get_id(np, "saif");
670 		if (saif->id < 0)
671 			return saif->id;
672 		/*
673 		 * If there is no "fsl,saif-master" phandle, it's a saif
674 		 * master.  Otherwise, it's a slave and its phandle points
675 		 * to the master.
676 		 */
677 		master = of_parse_phandle(np, "fsl,saif-master", 0);
678 		if (!master) {
679 			saif->master_id = saif->id;
680 		} else {
681 			saif->master_id = of_alias_get_id(master, "saif");
682 			if (saif->master_id < 0)
683 				return saif->master_id;
684 		}
685 	} else {
686 		saif->id = pdev->id;
687 		pdata = pdev->dev.platform_data;
688 		if (pdata && !pdata->master_mode)
689 			saif->master_id = pdata->master_id;
690 		else
691 			saif->master_id = saif->id;
692 	}
693 
694 	if (saif->master_id < 0 || saif->master_id >= ARRAY_SIZE(mxs_saif)) {
695 		dev_err(&pdev->dev, "get wrong master id\n");
696 		return -EINVAL;
697 	}
698 
699 	mxs_saif[saif->id] = saif;
700 
701 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
702 	if (IS_ERR(pinctrl)) {
703 		ret = PTR_ERR(pinctrl);
704 		return ret;
705 	}
706 
707 	saif->clk = clk_get(&pdev->dev, NULL);
708 	if (IS_ERR(saif->clk)) {
709 		ret = PTR_ERR(saif->clk);
710 		dev_err(&pdev->dev, "Cannot get the clock: %d\n",
711 			ret);
712 		return ret;
713 	}
714 
715 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
716 
717 	saif->base = devm_request_and_ioremap(&pdev->dev, iores);
718 	if (!saif->base) {
719 		dev_err(&pdev->dev, "ioremap failed\n");
720 		ret = -ENODEV;
721 		goto failed_get_resource;
722 	}
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 			goto failed_get_resource;
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 		goto failed_get_resource;
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 		goto failed_get_resource;
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 		goto failed_get_resource;
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 		goto failed_get_resource;
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 failed_get_resource:
783 	clk_put(saif->clk);
784 
785 	return ret;
786 }
787 
788 static int __devexit mxs_saif_remove(struct platform_device *pdev)
789 {
790 	struct mxs_saif *saif = platform_get_drvdata(pdev);
791 
792 	mxs_pcm_platform_unregister(&pdev->dev);
793 	snd_soc_unregister_dai(&pdev->dev);
794 	clk_put(saif->clk);
795 
796 	return 0;
797 }
798 
799 static const struct of_device_id mxs_saif_dt_ids[] = {
800 	{ .compatible = "fsl,imx28-saif", },
801 	{ /* sentinel */ }
802 };
803 MODULE_DEVICE_TABLE(of, mxs_saif_dt_ids);
804 
805 static struct platform_driver mxs_saif_driver = {
806 	.probe = mxs_saif_probe,
807 	.remove = __devexit_p(mxs_saif_remove),
808 
809 	.driver = {
810 		.name = "mxs-saif",
811 		.owner = THIS_MODULE,
812 		.of_match_table = mxs_saif_dt_ids,
813 	},
814 };
815 
816 module_platform_driver(mxs_saif_driver);
817 
818 MODULE_AUTHOR("Freescale Semiconductor, Inc.");
819 MODULE_DESCRIPTION("MXS ASoC SAIF driver");
820 MODULE_LICENSE("GPL");
821