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/clk-provider.h>
28#include <linux/delay.h>
29#include <linux/time.h>
30#include <sound/core.h>
31#include <sound/pcm.h>
32#include <sound/pcm_params.h>
33#include <sound/soc.h>
34
35#include "mxs-saif.h"
36
37#define MXS_SET_ADDR	0x4
38#define MXS_CLR_ADDR	0x8
39
40static struct mxs_saif *mxs_saif[2];
41
42/*
43 * SAIF is a little different with other normal SOC DAIs on clock using.
44 *
45 * For MXS, two SAIF modules are instantiated on-chip.
46 * Each SAIF has a set of clock pins and can be operating in master
47 * mode simultaneously if they are connected to different off-chip codecs.
48 * Also, one of the two SAIFs can master or drive the clock pins while the
49 * other SAIF, in slave mode, receives clocking from the master SAIF.
50 * This also means that both SAIFs must operate at the same sample rate.
51 *
52 * We abstract this as each saif has a master, the master could be
53 * itself or other saifs. In the generic saif driver, saif does not need
54 * to know the different clkmux. Saif only needs to know who is its master
55 * and operating its master to generate the proper clock rate for it.
56 * The master id is provided in mach-specific layer according to different
57 * clkmux setting.
58 */
59
60static int mxs_saif_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
61			int clk_id, unsigned int freq, int dir)
62{
63	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
64
65	switch (clk_id) {
66	case MXS_SAIF_MCLK:
67		saif->mclk = freq;
68		break;
69	default:
70		return -EINVAL;
71	}
72	return 0;
73}
74
75/*
76 * Since SAIF may work on EXTMASTER mode, IOW, it's working BITCLK&LRCLK
77 * is provided by other SAIF, we provide a interface here to get its master
78 * from its master_id.
79 * Note that the master could be itself.
80 */
81static inline struct mxs_saif *mxs_saif_get_master(struct mxs_saif * saif)
82{
83	return mxs_saif[saif->master_id];
84}
85
86/*
87 * Set SAIF clock and MCLK
88 */
89static int mxs_saif_set_clk(struct mxs_saif *saif,
90				  unsigned int mclk,
91				  unsigned int rate)
92{
93	u32 scr;
94	int ret;
95	struct mxs_saif *master_saif;
96
97	dev_dbg(saif->dev, "mclk %d rate %d\n", mclk, rate);
98
99	/* Set master saif to generate proper clock */
100	master_saif = mxs_saif_get_master(saif);
101	if (!master_saif)
102		return -EINVAL;
103
104	dev_dbg(saif->dev, "master saif%d\n", master_saif->id);
105
106	/* Checking if can playback and capture simutaneously */
107	if (master_saif->ongoing && rate != master_saif->cur_rate) {
108		dev_err(saif->dev,
109			"can not change clock, master saif%d(rate %d) is ongoing\n",
110			master_saif->id, master_saif->cur_rate);
111		return -EINVAL;
112	}
113
114	scr = __raw_readl(master_saif->base + SAIF_CTRL);
115	scr &= ~BM_SAIF_CTRL_BITCLK_MULT_RATE;
116	scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
117
118	/*
119	 * Set SAIF clock
120	 *
121	 * The SAIF clock should be either 384*fs or 512*fs.
122	 * If MCLK is used, the SAIF clk ratio need to match mclk ratio.
123	 *  For 32x mclk, set saif clk as 512*fs.
124	 *  For 48x mclk, set saif clk as 384*fs.
125	 *
126	 * If MCLK is not used, we just set saif clk to 512*fs.
127	 */
128	clk_prepare_enable(master_saif->clk);
129
130	if (master_saif->mclk_in_use) {
131		if (mclk % 32 == 0) {
132			scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
133			ret = clk_set_rate(master_saif->clk, 512 * rate);
134		} else if (mclk % 48 == 0) {
135			scr |= BM_SAIF_CTRL_BITCLK_BASE_RATE;
136			ret = clk_set_rate(master_saif->clk, 384 * rate);
137		} else {
138			/* SAIF MCLK should be either 32x or 48x */
139			clk_disable_unprepare(master_saif->clk);
140			return -EINVAL;
141		}
142	} else {
143		ret = clk_set_rate(master_saif->clk, 512 * rate);
144		scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
145	}
146
147	clk_disable_unprepare(master_saif->clk);
148
149	if (ret)
150		return ret;
151
152	master_saif->cur_rate = rate;
153
154	if (!master_saif->mclk_in_use) {
155		__raw_writel(scr, master_saif->base + SAIF_CTRL);
156		return 0;
157	}
158
159	/*
160	 * Program the over-sample rate for MCLK output
161	 *
162	 * The available MCLK range is 32x, 48x... 512x. The rate
163	 * could be from 8kHz to 192kH.
164	 */
165	switch (mclk / rate) {
166	case 32:
167		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(4);
168		break;
169	case 64:
170		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(3);
171		break;
172	case 128:
173		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(2);
174		break;
175	case 256:
176		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(1);
177		break;
178	case 512:
179		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(0);
180		break;
181	case 48:
182		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(3);
183		break;
184	case 96:
185		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(2);
186		break;
187	case 192:
188		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(1);
189		break;
190	case 384:
191		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(0);
192		break;
193	default:
194		return -EINVAL;
195	}
196
197	__raw_writel(scr, master_saif->base + SAIF_CTRL);
198
199	return 0;
200}
201
202/*
203 * Put and disable MCLK.
204 */
205int mxs_saif_put_mclk(unsigned int saif_id)
206{
207	struct mxs_saif *saif = mxs_saif[saif_id];
208	u32 stat;
209
210	if (!saif)
211		return -EINVAL;
212
213	stat = __raw_readl(saif->base + SAIF_STAT);
214	if (stat & BM_SAIF_STAT_BUSY) {
215		dev_err(saif->dev, "error: busy\n");
216		return -EBUSY;
217	}
218
219	clk_disable_unprepare(saif->clk);
220
221	/* disable MCLK output */
222	__raw_writel(BM_SAIF_CTRL_CLKGATE,
223		saif->base + SAIF_CTRL + MXS_SET_ADDR);
224	__raw_writel(BM_SAIF_CTRL_RUN,
225		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
226
227	saif->mclk_in_use = 0;
228	return 0;
229}
230EXPORT_SYMBOL_GPL(mxs_saif_put_mclk);
231
232/*
233 * Get MCLK and set clock rate, then enable it
234 *
235 * This interface is used for codecs who are using MCLK provided
236 * by saif.
237 */
238int mxs_saif_get_mclk(unsigned int saif_id, unsigned int mclk,
239					unsigned int rate)
240{
241	struct mxs_saif *saif = mxs_saif[saif_id];
242	u32 stat;
243	int ret;
244	struct mxs_saif *master_saif;
245
246	if (!saif)
247		return -EINVAL;
248
249	/* Clear Reset */
250	__raw_writel(BM_SAIF_CTRL_SFTRST,
251		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
252
253	/* FIXME: need clear clk gate for register r/w */
254	__raw_writel(BM_SAIF_CTRL_CLKGATE,
255		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
256
257	master_saif = mxs_saif_get_master(saif);
258	if (saif != master_saif) {
259		dev_err(saif->dev, "can not get mclk from a non-master saif\n");
260		return -EINVAL;
261	}
262
263	stat = __raw_readl(saif->base + SAIF_STAT);
264	if (stat & BM_SAIF_STAT_BUSY) {
265		dev_err(saif->dev, "error: busy\n");
266		return -EBUSY;
267	}
268
269	saif->mclk_in_use = 1;
270	ret = mxs_saif_set_clk(saif, mclk, rate);
271	if (ret)
272		return ret;
273
274	ret = clk_prepare_enable(saif->clk);
275	if (ret)
276		return ret;
277
278	/* enable MCLK output */
279	__raw_writel(BM_SAIF_CTRL_RUN,
280		saif->base + SAIF_CTRL + MXS_SET_ADDR);
281
282	return 0;
283}
284EXPORT_SYMBOL_GPL(mxs_saif_get_mclk);
285
286/*
287 * SAIF DAI format configuration.
288 * Should only be called when port is inactive.
289 */
290static 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
367static 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
372	/* clear error status to 0 for each re-open */
373	saif->fifo_underrun = 0;
374	saif->fifo_overrun = 0;
375
376	/* Clear Reset for normal operations */
377	__raw_writel(BM_SAIF_CTRL_SFTRST,
378		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
379
380	/* clear clock gate */
381	__raw_writel(BM_SAIF_CTRL_CLKGATE,
382		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
383
384	return 0;
385}
386
387/*
388 * Should only be called when port is inactive.
389 * although can be called multiple times by upper layers.
390 */
391static int mxs_saif_hw_params(struct snd_pcm_substream *substream,
392			     struct snd_pcm_hw_params *params,
393			     struct snd_soc_dai *cpu_dai)
394{
395	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
396	struct mxs_saif *master_saif;
397	u32 scr, stat;
398	int ret;
399
400	master_saif = mxs_saif_get_master(saif);
401	if (!master_saif)
402		return -EINVAL;
403
404	/* mclk should already be set */
405	if (!saif->mclk && saif->mclk_in_use) {
406		dev_err(cpu_dai->dev, "set mclk first\n");
407		return -EINVAL;
408	}
409
410	stat = __raw_readl(saif->base + SAIF_STAT);
411	if (stat & BM_SAIF_STAT_BUSY) {
412		dev_err(cpu_dai->dev, "error: busy\n");
413		return -EBUSY;
414	}
415
416	/*
417	 * Set saif clk based on sample rate.
418	 * If mclk is used, we also set mclk, if not, saif->mclk is
419	 * default 0, means not used.
420	 */
421	ret = mxs_saif_set_clk(saif, saif->mclk, params_rate(params));
422	if (ret) {
423		dev_err(cpu_dai->dev, "unable to get proper clk\n");
424		return ret;
425	}
426
427	/* prepare clk in hw_param, enable in trigger */
428	clk_prepare(saif->clk);
429	if (saif != master_saif) {
430		/*
431		* Set an initial clock rate for the saif internal logic to work
432		* properly. This is important when working in EXTMASTER mode
433		* that uses the other saif's BITCLK&LRCLK but it still needs a
434		* basic clock which should be fast enough for the internal
435		* logic.
436		*/
437		clk_enable(saif->clk);
438		ret = clk_set_rate(saif->clk, 24000000);
439		clk_disable(saif->clk);
440		if (ret)
441			return ret;
442
443		clk_prepare(master_saif->clk);
444	}
445
446	scr = __raw_readl(saif->base + SAIF_CTRL);
447
448	scr &= ~BM_SAIF_CTRL_WORD_LENGTH;
449	scr &= ~BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
450	switch (params_format(params)) {
451	case SNDRV_PCM_FORMAT_S16_LE:
452		scr |= BF_SAIF_CTRL_WORD_LENGTH(0);
453		break;
454	case SNDRV_PCM_FORMAT_S20_3LE:
455		scr |= BF_SAIF_CTRL_WORD_LENGTH(4);
456		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
457		break;
458	case SNDRV_PCM_FORMAT_S24_LE:
459		scr |= BF_SAIF_CTRL_WORD_LENGTH(8);
460		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
461		break;
462	default:
463		return -EINVAL;
464	}
465
466	/* Tx/Rx config */
467	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
468		/* enable TX mode */
469		scr &= ~BM_SAIF_CTRL_READ_MODE;
470	} else {
471		/* enable RX mode */
472		scr |= BM_SAIF_CTRL_READ_MODE;
473	}
474
475	__raw_writel(scr, saif->base + SAIF_CTRL);
476	return 0;
477}
478
479static int mxs_saif_prepare(struct snd_pcm_substream *substream,
480			   struct snd_soc_dai *cpu_dai)
481{
482	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
483
484	/* enable FIFO error irqs */
485	__raw_writel(BM_SAIF_CTRL_FIFO_ERROR_IRQ_EN,
486		saif->base + SAIF_CTRL + MXS_SET_ADDR);
487
488	return 0;
489}
490
491static int mxs_saif_trigger(struct snd_pcm_substream *substream, int cmd,
492				struct snd_soc_dai *cpu_dai)
493{
494	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
495	struct mxs_saif *master_saif;
496	u32 delay;
497	int ret;
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		if (saif->state == MXS_SAIF_STATE_RUNNING)
508			return 0;
509
510		dev_dbg(cpu_dai->dev, "start\n");
511
512		ret = clk_enable(master_saif->clk);
513		if (ret) {
514			dev_err(saif->dev, "Failed to enable master clock\n");
515			return ret;
516		}
517
518		/*
519		 * If the saif's master is not itself, we also need to enable
520		 * itself clk for its internal basic logic to work.
521		 */
522		if (saif != master_saif) {
523			ret = clk_enable(saif->clk);
524			if (ret) {
525				dev_err(saif->dev, "Failed to enable master clock\n");
526				clk_disable(master_saif->clk);
527				return ret;
528			}
529
530			__raw_writel(BM_SAIF_CTRL_RUN,
531				saif->base + SAIF_CTRL + MXS_SET_ADDR);
532		}
533
534		if (!master_saif->mclk_in_use)
535			__raw_writel(BM_SAIF_CTRL_RUN,
536				master_saif->base + SAIF_CTRL + MXS_SET_ADDR);
537
538		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
539			/*
540			 * write data to saif data register to trigger
541			 * the transfer.
542			 * For 24-bit format the 32-bit FIFO register stores
543			 * only one channel, so we need to write twice.
544			 * This is also safe for the other non 24-bit formats.
545			 */
546			__raw_writel(0, saif->base + SAIF_DATA);
547			__raw_writel(0, saif->base + SAIF_DATA);
548		} else {
549			/*
550			 * read data from saif data register to trigger
551			 * the receive.
552			 * For 24-bit format the 32-bit FIFO register stores
553			 * only one channel, so we need to read twice.
554			 * This is also safe for the other non 24-bit formats.
555			 */
556			__raw_readl(saif->base + SAIF_DATA);
557			__raw_readl(saif->base + SAIF_DATA);
558		}
559
560		master_saif->ongoing = 1;
561		saif->state = MXS_SAIF_STATE_RUNNING;
562
563		dev_dbg(saif->dev, "CTRL 0x%x STAT 0x%x\n",
564			__raw_readl(saif->base + SAIF_CTRL),
565			__raw_readl(saif->base + SAIF_STAT));
566
567		dev_dbg(master_saif->dev, "CTRL 0x%x STAT 0x%x\n",
568			__raw_readl(master_saif->base + SAIF_CTRL),
569			__raw_readl(master_saif->base + SAIF_STAT));
570		break;
571	case SNDRV_PCM_TRIGGER_SUSPEND:
572	case SNDRV_PCM_TRIGGER_STOP:
573	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
574		if (saif->state == MXS_SAIF_STATE_STOPPED)
575			return 0;
576
577		dev_dbg(cpu_dai->dev, "stop\n");
578
579		/* wait a while for the current sample to complete */
580		delay = USEC_PER_SEC / master_saif->cur_rate;
581
582		if (!master_saif->mclk_in_use) {
583			__raw_writel(BM_SAIF_CTRL_RUN,
584				master_saif->base + SAIF_CTRL + MXS_CLR_ADDR);
585			udelay(delay);
586		}
587		clk_disable(master_saif->clk);
588
589		if (saif != master_saif) {
590			__raw_writel(BM_SAIF_CTRL_RUN,
591				saif->base + SAIF_CTRL + MXS_CLR_ADDR);
592			udelay(delay);
593			clk_disable(saif->clk);
594		}
595
596		master_saif->ongoing = 0;
597		saif->state = MXS_SAIF_STATE_STOPPED;
598
599		break;
600	default:
601		return -EINVAL;
602	}
603
604	return 0;
605}
606
607#define MXS_SAIF_RATES		SNDRV_PCM_RATE_8000_192000
608#define MXS_SAIF_FORMATS \
609	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
610	SNDRV_PCM_FMTBIT_S24_LE)
611
612static const struct snd_soc_dai_ops mxs_saif_dai_ops = {
613	.startup = mxs_saif_startup,
614	.trigger = mxs_saif_trigger,
615	.prepare = mxs_saif_prepare,
616	.hw_params = mxs_saif_hw_params,
617	.set_sysclk = mxs_saif_set_dai_sysclk,
618	.set_fmt = mxs_saif_set_dai_fmt,
619};
620
621static int mxs_saif_dai_probe(struct snd_soc_dai *dai)
622{
623	struct mxs_saif *saif = dev_get_drvdata(dai->dev);
624
625	snd_soc_dai_set_drvdata(dai, saif);
626
627	return 0;
628}
629
630static struct snd_soc_dai_driver mxs_saif_dai = {
631	.name = "mxs-saif",
632	.probe = mxs_saif_dai_probe,
633	.playback = {
634		.channels_min = 2,
635		.channels_max = 2,
636		.rates = MXS_SAIF_RATES,
637		.formats = MXS_SAIF_FORMATS,
638	},
639	.capture = {
640		.channels_min = 2,
641		.channels_max = 2,
642		.rates = MXS_SAIF_RATES,
643		.formats = MXS_SAIF_FORMATS,
644	},
645	.ops = &mxs_saif_dai_ops,
646};
647
648static const struct snd_soc_component_driver mxs_saif_component = {
649	.name		= "mxs-saif",
650};
651
652static irqreturn_t mxs_saif_irq(int irq, void *dev_id)
653{
654	struct mxs_saif *saif = dev_id;
655	unsigned int stat;
656
657	stat = __raw_readl(saif->base + SAIF_STAT);
658	if (!(stat & (BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ |
659			BM_SAIF_STAT_FIFO_OVERFLOW_IRQ)))
660		return IRQ_NONE;
661
662	if (stat & BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ) {
663		dev_dbg(saif->dev, "underrun!!! %d\n", ++saif->fifo_underrun);
664		__raw_writel(BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ,
665				saif->base + SAIF_STAT + MXS_CLR_ADDR);
666	}
667
668	if (stat & BM_SAIF_STAT_FIFO_OVERFLOW_IRQ) {
669		dev_dbg(saif->dev, "overrun!!! %d\n", ++saif->fifo_overrun);
670		__raw_writel(BM_SAIF_STAT_FIFO_OVERFLOW_IRQ,
671				saif->base + SAIF_STAT + MXS_CLR_ADDR);
672	}
673
674	dev_dbg(saif->dev, "SAIF_CTRL %x SAIF_STAT %x\n",
675	       __raw_readl(saif->base + SAIF_CTRL),
676	       __raw_readl(saif->base + SAIF_STAT));
677
678	return IRQ_HANDLED;
679}
680
681static int mxs_saif_mclk_init(struct platform_device *pdev)
682{
683	struct mxs_saif *saif = platform_get_drvdata(pdev);
684	struct device_node *np = pdev->dev.of_node;
685	struct clk *clk;
686	int ret;
687
688	clk = clk_register_divider(&pdev->dev, "mxs_saif_mclk",
689				   __clk_get_name(saif->clk), 0,
690				   saif->base + SAIF_CTRL,
691				   BP_SAIF_CTRL_BITCLK_MULT_RATE, 3,
692				   0, NULL);
693	if (IS_ERR(clk)) {
694		ret = PTR_ERR(clk);
695		if (ret == -EEXIST)
696			return 0;
697		dev_err(&pdev->dev, "failed to register mclk: %d\n", ret);
698		return PTR_ERR(clk);
699	}
700
701	ret = of_clk_add_provider(np, of_clk_src_simple_get, clk);
702	if (ret)
703		return ret;
704
705	return 0;
706}
707
708static int mxs_saif_probe(struct platform_device *pdev)
709{
710	struct device_node *np = pdev->dev.of_node;
711	struct resource *iores;
712	struct mxs_saif *saif;
713	int irq, ret = 0;
714	struct device_node *master;
715
716	if (!np)
717		return -EINVAL;
718
719	saif = devm_kzalloc(&pdev->dev, sizeof(*saif), GFP_KERNEL);
720	if (!saif)
721		return -ENOMEM;
722
723	ret = of_alias_get_id(np, "saif");
724	if (ret < 0)
725		return ret;
726	else
727		saif->id = ret;
728
729	/*
730	 * If there is no "fsl,saif-master" phandle, it's a saif
731	 * master.  Otherwise, it's a slave and its phandle points
732	 * to the master.
733	 */
734	master = of_parse_phandle(np, "fsl,saif-master", 0);
735	if (!master) {
736		saif->master_id = saif->id;
737	} else {
738		ret = of_alias_get_id(master, "saif");
739		if (ret < 0)
740			return ret;
741		else
742			saif->master_id = ret;
743	}
744
745	if (saif->master_id >= ARRAY_SIZE(mxs_saif)) {
746		dev_err(&pdev->dev, "get wrong master id\n");
747		return -EINVAL;
748	}
749
750	mxs_saif[saif->id] = saif;
751
752	saif->clk = devm_clk_get(&pdev->dev, NULL);
753	if (IS_ERR(saif->clk)) {
754		ret = PTR_ERR(saif->clk);
755		dev_err(&pdev->dev, "Cannot get the clock: %d\n",
756			ret);
757		return ret;
758	}
759
760	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
761
762	saif->base = devm_ioremap_resource(&pdev->dev, iores);
763	if (IS_ERR(saif->base))
764		return PTR_ERR(saif->base);
765
766	irq = platform_get_irq(pdev, 0);
767	if (irq < 0) {
768		ret = irq;
769		dev_err(&pdev->dev, "failed to get irq resource: %d\n",
770			ret);
771		return ret;
772	}
773
774	saif->dev = &pdev->dev;
775	ret = devm_request_irq(&pdev->dev, irq, mxs_saif_irq, 0,
776			       dev_name(&pdev->dev), saif);
777	if (ret) {
778		dev_err(&pdev->dev, "failed to request irq\n");
779		return ret;
780	}
781
782	platform_set_drvdata(pdev, saif);
783
784	/* We only support saif0 being tx and clock master */
785	if (saif->id == 0) {
786		ret = mxs_saif_mclk_init(pdev);
787		if (ret)
788			dev_warn(&pdev->dev, "failed to init clocks\n");
789	}
790
791	ret = devm_snd_soc_register_component(&pdev->dev, &mxs_saif_component,
792					      &mxs_saif_dai, 1);
793	if (ret) {
794		dev_err(&pdev->dev, "register DAI failed\n");
795		return ret;
796	}
797
798	ret = mxs_pcm_platform_register(&pdev->dev);
799	if (ret) {
800		dev_err(&pdev->dev, "register PCM failed: %d\n", ret);
801		return ret;
802	}
803
804	return 0;
805}
806
807static const struct of_device_id mxs_saif_dt_ids[] = {
808	{ .compatible = "fsl,imx28-saif", },
809	{ /* sentinel */ }
810};
811MODULE_DEVICE_TABLE(of, mxs_saif_dt_ids);
812
813static struct platform_driver mxs_saif_driver = {
814	.probe = mxs_saif_probe,
815
816	.driver = {
817		.name = "mxs-saif",
818		.of_match_table = mxs_saif_dt_ids,
819	},
820};
821
822module_platform_driver(mxs_saif_driver);
823
824MODULE_AUTHOR("Freescale Semiconductor, Inc.");
825MODULE_DESCRIPTION("MXS ASoC SAIF driver");
826MODULE_LICENSE("GPL");
827MODULE_ALIAS("platform:mxs-saif");
828