xref: /openbmc/linux/sound/soc/fsl/fsl_sai.c (revision bc5aa3a0)
1 /*
2  * Freescale ALSA SoC Digital Audio Interface (SAI) driver.
3  *
4  * Copyright 2012-2015 Freescale Semiconductor, Inc.
5  *
6  * This program is free software, you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the
8  * Free Software Foundation, either version 2 of the License, or(at your
9  * option) any later version.
10  *
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/delay.h>
15 #include <linux/dmaengine.h>
16 #include <linux/module.h>
17 #include <linux/of_address.h>
18 #include <linux/regmap.h>
19 #include <linux/slab.h>
20 #include <linux/time.h>
21 #include <sound/core.h>
22 #include <sound/dmaengine_pcm.h>
23 #include <sound/pcm_params.h>
24 #include <linux/mfd/syscon.h>
25 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
26 
27 #include "fsl_sai.h"
28 #include "imx-pcm.h"
29 
30 #define FSL_SAI_FLAGS (FSL_SAI_CSR_SEIE |\
31 		       FSL_SAI_CSR_FEIE)
32 
33 static const unsigned int fsl_sai_rates[] = {
34 	8000, 11025, 12000, 16000, 22050,
35 	24000, 32000, 44100, 48000, 64000,
36 	88200, 96000, 176400, 192000
37 };
38 
39 static const struct snd_pcm_hw_constraint_list fsl_sai_rate_constraints = {
40 	.count = ARRAY_SIZE(fsl_sai_rates),
41 	.list = fsl_sai_rates,
42 };
43 
44 static irqreturn_t fsl_sai_isr(int irq, void *devid)
45 {
46 	struct fsl_sai *sai = (struct fsl_sai *)devid;
47 	struct device *dev = &sai->pdev->dev;
48 	u32 flags, xcsr, mask;
49 	bool irq_none = true;
50 
51 	/*
52 	 * Both IRQ status bits and IRQ mask bits are in the xCSR but
53 	 * different shifts. And we here create a mask only for those
54 	 * IRQs that we activated.
55 	 */
56 	mask = (FSL_SAI_FLAGS >> FSL_SAI_CSR_xIE_SHIFT) << FSL_SAI_CSR_xF_SHIFT;
57 
58 	/* Tx IRQ */
59 	regmap_read(sai->regmap, FSL_SAI_TCSR, &xcsr);
60 	flags = xcsr & mask;
61 
62 	if (flags)
63 		irq_none = false;
64 	else
65 		goto irq_rx;
66 
67 	if (flags & FSL_SAI_CSR_WSF)
68 		dev_dbg(dev, "isr: Start of Tx word detected\n");
69 
70 	if (flags & FSL_SAI_CSR_SEF)
71 		dev_warn(dev, "isr: Tx Frame sync error detected\n");
72 
73 	if (flags & FSL_SAI_CSR_FEF) {
74 		dev_warn(dev, "isr: Transmit underrun detected\n");
75 		/* FIFO reset for safety */
76 		xcsr |= FSL_SAI_CSR_FR;
77 	}
78 
79 	if (flags & FSL_SAI_CSR_FWF)
80 		dev_dbg(dev, "isr: Enabled transmit FIFO is empty\n");
81 
82 	if (flags & FSL_SAI_CSR_FRF)
83 		dev_dbg(dev, "isr: Transmit FIFO watermark has been reached\n");
84 
85 	flags &= FSL_SAI_CSR_xF_W_MASK;
86 	xcsr &= ~FSL_SAI_CSR_xF_MASK;
87 
88 	if (flags)
89 		regmap_write(sai->regmap, FSL_SAI_TCSR, flags | xcsr);
90 
91 irq_rx:
92 	/* Rx IRQ */
93 	regmap_read(sai->regmap, FSL_SAI_RCSR, &xcsr);
94 	flags = xcsr & mask;
95 
96 	if (flags)
97 		irq_none = false;
98 	else
99 		goto out;
100 
101 	if (flags & FSL_SAI_CSR_WSF)
102 		dev_dbg(dev, "isr: Start of Rx word detected\n");
103 
104 	if (flags & FSL_SAI_CSR_SEF)
105 		dev_warn(dev, "isr: Rx Frame sync error detected\n");
106 
107 	if (flags & FSL_SAI_CSR_FEF) {
108 		dev_warn(dev, "isr: Receive overflow detected\n");
109 		/* FIFO reset for safety */
110 		xcsr |= FSL_SAI_CSR_FR;
111 	}
112 
113 	if (flags & FSL_SAI_CSR_FWF)
114 		dev_dbg(dev, "isr: Enabled receive FIFO is full\n");
115 
116 	if (flags & FSL_SAI_CSR_FRF)
117 		dev_dbg(dev, "isr: Receive FIFO watermark has been reached\n");
118 
119 	flags &= FSL_SAI_CSR_xF_W_MASK;
120 	xcsr &= ~FSL_SAI_CSR_xF_MASK;
121 
122 	if (flags)
123 		regmap_write(sai->regmap, FSL_SAI_RCSR, flags | xcsr);
124 
125 out:
126 	if (irq_none)
127 		return IRQ_NONE;
128 	else
129 		return IRQ_HANDLED;
130 }
131 
132 static int fsl_sai_set_dai_tdm_slot(struct snd_soc_dai *cpu_dai, u32 tx_mask,
133 				u32 rx_mask, int slots, int slot_width)
134 {
135 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
136 
137 	sai->slots = slots;
138 	sai->slot_width = slot_width;
139 
140 	return 0;
141 }
142 
143 static int fsl_sai_set_dai_sysclk_tr(struct snd_soc_dai *cpu_dai,
144 		int clk_id, unsigned int freq, int fsl_dir)
145 {
146 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
147 	bool tx = fsl_dir == FSL_FMT_TRANSMITTER;
148 	u32 val_cr2 = 0;
149 
150 	switch (clk_id) {
151 	case FSL_SAI_CLK_BUS:
152 		val_cr2 |= FSL_SAI_CR2_MSEL_BUS;
153 		break;
154 	case FSL_SAI_CLK_MAST1:
155 		val_cr2 |= FSL_SAI_CR2_MSEL_MCLK1;
156 		break;
157 	case FSL_SAI_CLK_MAST2:
158 		val_cr2 |= FSL_SAI_CR2_MSEL_MCLK2;
159 		break;
160 	case FSL_SAI_CLK_MAST3:
161 		val_cr2 |= FSL_SAI_CR2_MSEL_MCLK3;
162 		break;
163 	default:
164 		return -EINVAL;
165 	}
166 
167 	regmap_update_bits(sai->regmap, FSL_SAI_xCR2(tx),
168 			   FSL_SAI_CR2_MSEL_MASK, val_cr2);
169 
170 	return 0;
171 }
172 
173 static int fsl_sai_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
174 		int clk_id, unsigned int freq, int dir)
175 {
176 	int ret;
177 
178 	if (dir == SND_SOC_CLOCK_IN)
179 		return 0;
180 
181 	ret = fsl_sai_set_dai_sysclk_tr(cpu_dai, clk_id, freq,
182 					FSL_FMT_TRANSMITTER);
183 	if (ret) {
184 		dev_err(cpu_dai->dev, "Cannot set tx sysclk: %d\n", ret);
185 		return ret;
186 	}
187 
188 	ret = fsl_sai_set_dai_sysclk_tr(cpu_dai, clk_id, freq,
189 					FSL_FMT_RECEIVER);
190 	if (ret)
191 		dev_err(cpu_dai->dev, "Cannot set rx sysclk: %d\n", ret);
192 
193 	return ret;
194 }
195 
196 static int fsl_sai_set_dai_fmt_tr(struct snd_soc_dai *cpu_dai,
197 				unsigned int fmt, int fsl_dir)
198 {
199 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
200 	bool tx = fsl_dir == FSL_FMT_TRANSMITTER;
201 	u32 val_cr2 = 0, val_cr4 = 0;
202 
203 	if (!sai->is_lsb_first)
204 		val_cr4 |= FSL_SAI_CR4_MF;
205 
206 	/* DAI mode */
207 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
208 	case SND_SOC_DAIFMT_I2S:
209 		/*
210 		 * Frame low, 1clk before data, one word length for frame sync,
211 		 * frame sync starts one serial clock cycle earlier,
212 		 * that is, together with the last bit of the previous
213 		 * data word.
214 		 */
215 		val_cr2 |= FSL_SAI_CR2_BCP;
216 		val_cr4 |= FSL_SAI_CR4_FSE | FSL_SAI_CR4_FSP;
217 		break;
218 	case SND_SOC_DAIFMT_LEFT_J:
219 		/*
220 		 * Frame high, one word length for frame sync,
221 		 * frame sync asserts with the first bit of the frame.
222 		 */
223 		val_cr2 |= FSL_SAI_CR2_BCP;
224 		break;
225 	case SND_SOC_DAIFMT_DSP_A:
226 		/*
227 		 * Frame high, 1clk before data, one bit for frame sync,
228 		 * frame sync starts one serial clock cycle earlier,
229 		 * that is, together with the last bit of the previous
230 		 * data word.
231 		 */
232 		val_cr2 |= FSL_SAI_CR2_BCP;
233 		val_cr4 |= FSL_SAI_CR4_FSE;
234 		sai->is_dsp_mode = true;
235 		break;
236 	case SND_SOC_DAIFMT_DSP_B:
237 		/*
238 		 * Frame high, one bit for frame sync,
239 		 * frame sync asserts with the first bit of the frame.
240 		 */
241 		val_cr2 |= FSL_SAI_CR2_BCP;
242 		sai->is_dsp_mode = true;
243 		break;
244 	case SND_SOC_DAIFMT_RIGHT_J:
245 		/* To be done */
246 	default:
247 		return -EINVAL;
248 	}
249 
250 	/* DAI clock inversion */
251 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
252 	case SND_SOC_DAIFMT_IB_IF:
253 		/* Invert both clocks */
254 		val_cr2 ^= FSL_SAI_CR2_BCP;
255 		val_cr4 ^= FSL_SAI_CR4_FSP;
256 		break;
257 	case SND_SOC_DAIFMT_IB_NF:
258 		/* Invert bit clock */
259 		val_cr2 ^= FSL_SAI_CR2_BCP;
260 		break;
261 	case SND_SOC_DAIFMT_NB_IF:
262 		/* Invert frame clock */
263 		val_cr4 ^= FSL_SAI_CR4_FSP;
264 		break;
265 	case SND_SOC_DAIFMT_NB_NF:
266 		/* Nothing to do for both normal cases */
267 		break;
268 	default:
269 		return -EINVAL;
270 	}
271 
272 	/* DAI clock master masks */
273 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
274 	case SND_SOC_DAIFMT_CBS_CFS:
275 		val_cr2 |= FSL_SAI_CR2_BCD_MSTR;
276 		val_cr4 |= FSL_SAI_CR4_FSD_MSTR;
277 		break;
278 	case SND_SOC_DAIFMT_CBM_CFM:
279 		sai->is_slave_mode = true;
280 		break;
281 	case SND_SOC_DAIFMT_CBS_CFM:
282 		val_cr2 |= FSL_SAI_CR2_BCD_MSTR;
283 		break;
284 	case SND_SOC_DAIFMT_CBM_CFS:
285 		val_cr4 |= FSL_SAI_CR4_FSD_MSTR;
286 		sai->is_slave_mode = true;
287 		break;
288 	default:
289 		return -EINVAL;
290 	}
291 
292 	regmap_update_bits(sai->regmap, FSL_SAI_xCR2(tx),
293 			   FSL_SAI_CR2_BCP | FSL_SAI_CR2_BCD_MSTR, val_cr2);
294 	regmap_update_bits(sai->regmap, FSL_SAI_xCR4(tx),
295 			   FSL_SAI_CR4_MF | FSL_SAI_CR4_FSE |
296 			   FSL_SAI_CR4_FSP | FSL_SAI_CR4_FSD_MSTR, val_cr4);
297 
298 	return 0;
299 }
300 
301 static int fsl_sai_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
302 {
303 	int ret;
304 
305 	ret = fsl_sai_set_dai_fmt_tr(cpu_dai, fmt, FSL_FMT_TRANSMITTER);
306 	if (ret) {
307 		dev_err(cpu_dai->dev, "Cannot set tx format: %d\n", ret);
308 		return ret;
309 	}
310 
311 	ret = fsl_sai_set_dai_fmt_tr(cpu_dai, fmt, FSL_FMT_RECEIVER);
312 	if (ret)
313 		dev_err(cpu_dai->dev, "Cannot set rx format: %d\n", ret);
314 
315 	return ret;
316 }
317 
318 static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq)
319 {
320 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(dai);
321 	unsigned long clk_rate;
322 	u32 savediv = 0, ratio, savesub = freq;
323 	u32 id;
324 	int ret = 0;
325 
326 	/* Don't apply to slave mode */
327 	if (sai->is_slave_mode)
328 		return 0;
329 
330 	for (id = 0; id < FSL_SAI_MCLK_MAX; id++) {
331 		clk_rate = clk_get_rate(sai->mclk_clk[id]);
332 		if (!clk_rate)
333 			continue;
334 
335 		ratio = clk_rate / freq;
336 
337 		ret = clk_rate - ratio * freq;
338 
339 		/*
340 		 * Drop the source that can not be
341 		 * divided into the required rate.
342 		 */
343 		if (ret != 0 && clk_rate / ret < 1000)
344 			continue;
345 
346 		dev_dbg(dai->dev,
347 			"ratio %d for freq %dHz based on clock %ldHz\n",
348 			ratio, freq, clk_rate);
349 
350 		if (ratio % 2 == 0 && ratio >= 2 && ratio <= 512)
351 			ratio /= 2;
352 		else
353 			continue;
354 
355 		if (ret < savesub) {
356 			savediv = ratio;
357 			sai->mclk_id[tx] = id;
358 			savesub = ret;
359 		}
360 
361 		if (ret == 0)
362 			break;
363 	}
364 
365 	if (savediv == 0) {
366 		dev_err(dai->dev, "failed to derive required %cx rate: %d\n",
367 				tx ? 'T' : 'R', freq);
368 		return -EINVAL;
369 	}
370 
371 	/*
372 	 * 1) For Asynchronous mode, we must set RCR2 register for capture, and
373 	 *    set TCR2 register for playback.
374 	 * 2) For Tx sync with Rx clock, we must set RCR2 register for playback
375 	 *    and capture.
376 	 * 3) For Rx sync with Tx clock, we must set TCR2 register for playback
377 	 *    and capture.
378 	 * 4) For Tx and Rx are both Synchronous with another SAI, we just
379 	 *    ignore it.
380 	 */
381 	if ((sai->synchronous[TX] && !sai->synchronous[RX]) ||
382 	    (!tx && !sai->synchronous[RX])) {
383 		regmap_update_bits(sai->regmap, FSL_SAI_RCR2,
384 				   FSL_SAI_CR2_MSEL_MASK,
385 				   FSL_SAI_CR2_MSEL(sai->mclk_id[tx]));
386 		regmap_update_bits(sai->regmap, FSL_SAI_RCR2,
387 				   FSL_SAI_CR2_DIV_MASK, savediv - 1);
388 	} else if ((sai->synchronous[RX] && !sai->synchronous[TX]) ||
389 		   (tx && !sai->synchronous[TX])) {
390 		regmap_update_bits(sai->regmap, FSL_SAI_TCR2,
391 				   FSL_SAI_CR2_MSEL_MASK,
392 				   FSL_SAI_CR2_MSEL(sai->mclk_id[tx]));
393 		regmap_update_bits(sai->regmap, FSL_SAI_TCR2,
394 				   FSL_SAI_CR2_DIV_MASK, savediv - 1);
395 	}
396 
397 	dev_dbg(dai->dev, "best fit: clock id=%d, div=%d, deviation =%d\n",
398 			sai->mclk_id[tx], savediv, savesub);
399 
400 	return 0;
401 }
402 
403 static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
404 		struct snd_pcm_hw_params *params,
405 		struct snd_soc_dai *cpu_dai)
406 {
407 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
408 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
409 	unsigned int channels = params_channels(params);
410 	u32 word_width = params_width(params);
411 	u32 val_cr4 = 0, val_cr5 = 0;
412 	u32 slots = (channels == 1) ? 2 : channels;
413 	u32 slot_width = word_width;
414 	int ret;
415 
416 	if (sai->slots)
417 		slots = sai->slots;
418 
419 	if (sai->slot_width)
420 		slot_width = sai->slot_width;
421 
422 	if (!sai->is_slave_mode) {
423 		ret = fsl_sai_set_bclk(cpu_dai, tx,
424 				slots * slot_width * params_rate(params));
425 		if (ret)
426 			return ret;
427 
428 		/* Do not enable the clock if it is already enabled */
429 		if (!(sai->mclk_streams & BIT(substream->stream))) {
430 			ret = clk_prepare_enable(sai->mclk_clk[sai->mclk_id[tx]]);
431 			if (ret)
432 				return ret;
433 
434 			sai->mclk_streams |= BIT(substream->stream);
435 		}
436 	}
437 
438 	if (!sai->is_dsp_mode)
439 		val_cr4 |= FSL_SAI_CR4_SYWD(slot_width);
440 
441 	val_cr5 |= FSL_SAI_CR5_WNW(slot_width);
442 	val_cr5 |= FSL_SAI_CR5_W0W(slot_width);
443 
444 	if (sai->is_lsb_first)
445 		val_cr5 |= FSL_SAI_CR5_FBT(0);
446 	else
447 		val_cr5 |= FSL_SAI_CR5_FBT(word_width - 1);
448 
449 	val_cr4 |= FSL_SAI_CR4_FRSZ(slots);
450 
451 	/*
452 	 * For SAI master mode, when Tx(Rx) sync with Rx(Tx) clock, Rx(Tx) will
453 	 * generate bclk and frame clock for Tx(Rx), we should set RCR4(TCR4),
454 	 * RCR5(TCR5) and RMR(TMR) for playback(capture), or there will be sync
455 	 * error.
456 	 */
457 
458 	if (!sai->is_slave_mode) {
459 		if (!sai->synchronous[TX] && sai->synchronous[RX] && !tx) {
460 			regmap_update_bits(sai->regmap, FSL_SAI_TCR4,
461 				FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
462 				val_cr4);
463 			regmap_update_bits(sai->regmap, FSL_SAI_TCR5,
464 				FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
465 				FSL_SAI_CR5_FBT_MASK, val_cr5);
466 			regmap_write(sai->regmap, FSL_SAI_TMR,
467 				~0UL - ((1 << channels) - 1));
468 		} else if (!sai->synchronous[RX] && sai->synchronous[TX] && tx) {
469 			regmap_update_bits(sai->regmap, FSL_SAI_RCR4,
470 				FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
471 				val_cr4);
472 			regmap_update_bits(sai->regmap, FSL_SAI_RCR5,
473 				FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
474 				FSL_SAI_CR5_FBT_MASK, val_cr5);
475 			regmap_write(sai->regmap, FSL_SAI_RMR,
476 				~0UL - ((1 << channels) - 1));
477 		}
478 	}
479 
480 	regmap_update_bits(sai->regmap, FSL_SAI_xCR4(tx),
481 			   FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
482 			   val_cr4);
483 	regmap_update_bits(sai->regmap, FSL_SAI_xCR5(tx),
484 			   FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
485 			   FSL_SAI_CR5_FBT_MASK, val_cr5);
486 	regmap_write(sai->regmap, FSL_SAI_xMR(tx), ~0UL - ((1 << channels) - 1));
487 
488 	return 0;
489 }
490 
491 static int fsl_sai_hw_free(struct snd_pcm_substream *substream,
492 		struct snd_soc_dai *cpu_dai)
493 {
494 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
495 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
496 
497 	if (!sai->is_slave_mode &&
498 			sai->mclk_streams & BIT(substream->stream)) {
499 		clk_disable_unprepare(sai->mclk_clk[sai->mclk_id[tx]]);
500 		sai->mclk_streams &= ~BIT(substream->stream);
501 	}
502 
503 	return 0;
504 }
505 
506 
507 static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
508 		struct snd_soc_dai *cpu_dai)
509 {
510 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
511 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
512 	u32 xcsr, count = 100;
513 
514 	/*
515 	 * Asynchronous mode: Clear SYNC for both Tx and Rx.
516 	 * Rx sync with Tx clocks: Clear SYNC for Tx, set it for Rx.
517 	 * Tx sync with Rx clocks: Clear SYNC for Rx, set it for Tx.
518 	 */
519 	regmap_update_bits(sai->regmap, FSL_SAI_TCR2, FSL_SAI_CR2_SYNC,
520 		           sai->synchronous[TX] ? FSL_SAI_CR2_SYNC : 0);
521 	regmap_update_bits(sai->regmap, FSL_SAI_RCR2, FSL_SAI_CR2_SYNC,
522 			   sai->synchronous[RX] ? FSL_SAI_CR2_SYNC : 0);
523 
524 	/*
525 	 * It is recommended that the transmitter is the last enabled
526 	 * and the first disabled.
527 	 */
528 	switch (cmd) {
529 	case SNDRV_PCM_TRIGGER_START:
530 	case SNDRV_PCM_TRIGGER_RESUME:
531 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
532 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx),
533 				   FSL_SAI_CSR_FRDE, FSL_SAI_CSR_FRDE);
534 
535 		regmap_update_bits(sai->regmap, FSL_SAI_RCSR,
536 				   FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
537 		regmap_update_bits(sai->regmap, FSL_SAI_TCSR,
538 				   FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
539 
540 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx),
541 				   FSL_SAI_CSR_xIE_MASK, FSL_SAI_FLAGS);
542 		break;
543 	case SNDRV_PCM_TRIGGER_STOP:
544 	case SNDRV_PCM_TRIGGER_SUSPEND:
545 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
546 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx),
547 				   FSL_SAI_CSR_FRDE, 0);
548 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx),
549 				   FSL_SAI_CSR_xIE_MASK, 0);
550 
551 		/* Check if the opposite FRDE is also disabled */
552 		regmap_read(sai->regmap, FSL_SAI_xCSR(!tx), &xcsr);
553 		if (!(xcsr & FSL_SAI_CSR_FRDE)) {
554 			/* Disable both directions and reset their FIFOs */
555 			regmap_update_bits(sai->regmap, FSL_SAI_TCSR,
556 					   FSL_SAI_CSR_TERE, 0);
557 			regmap_update_bits(sai->regmap, FSL_SAI_RCSR,
558 					   FSL_SAI_CSR_TERE, 0);
559 
560 			/* TERE will remain set till the end of current frame */
561 			do {
562 				udelay(10);
563 				regmap_read(sai->regmap, FSL_SAI_xCSR(tx), &xcsr);
564 			} while (--count && xcsr & FSL_SAI_CSR_TERE);
565 
566 			regmap_update_bits(sai->regmap, FSL_SAI_TCSR,
567 					   FSL_SAI_CSR_FR, FSL_SAI_CSR_FR);
568 			regmap_update_bits(sai->regmap, FSL_SAI_RCSR,
569 					   FSL_SAI_CSR_FR, FSL_SAI_CSR_FR);
570 
571 			/*
572 			 * For sai master mode, after several open/close sai,
573 			 * there will be no frame clock, and can't recover
574 			 * anymore. Add software reset to fix this issue.
575 			 * This is a hardware bug, and will be fix in the
576 			 * next sai version.
577 			 */
578 			if (!sai->is_slave_mode) {
579 				/* Software Reset for both Tx and Rx */
580 				regmap_write(sai->regmap,
581 					     FSL_SAI_TCSR, FSL_SAI_CSR_SR);
582 				regmap_write(sai->regmap,
583 					     FSL_SAI_RCSR, FSL_SAI_CSR_SR);
584 				/* Clear SR bit to finish the reset */
585 				regmap_write(sai->regmap, FSL_SAI_TCSR, 0);
586 				regmap_write(sai->regmap, FSL_SAI_RCSR, 0);
587 			}
588 		}
589 		break;
590 	default:
591 		return -EINVAL;
592 	}
593 
594 	return 0;
595 }
596 
597 static int fsl_sai_startup(struct snd_pcm_substream *substream,
598 		struct snd_soc_dai *cpu_dai)
599 {
600 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
601 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
602 	struct device *dev = &sai->pdev->dev;
603 	int ret;
604 
605 	ret = clk_prepare_enable(sai->bus_clk);
606 	if (ret) {
607 		dev_err(dev, "failed to enable bus clock: %d\n", ret);
608 		return ret;
609 	}
610 
611 	regmap_update_bits(sai->regmap, FSL_SAI_xCR3(tx), FSL_SAI_CR3_TRCE,
612 			   FSL_SAI_CR3_TRCE);
613 
614 	ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
615 			SNDRV_PCM_HW_PARAM_RATE, &fsl_sai_rate_constraints);
616 
617 	return ret;
618 }
619 
620 static void fsl_sai_shutdown(struct snd_pcm_substream *substream,
621 		struct snd_soc_dai *cpu_dai)
622 {
623 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
624 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
625 
626 	regmap_update_bits(sai->regmap, FSL_SAI_xCR3(tx), FSL_SAI_CR3_TRCE, 0);
627 
628 	clk_disable_unprepare(sai->bus_clk);
629 }
630 
631 static const struct snd_soc_dai_ops fsl_sai_pcm_dai_ops = {
632 	.set_sysclk	= fsl_sai_set_dai_sysclk,
633 	.set_fmt	= fsl_sai_set_dai_fmt,
634 	.set_tdm_slot	= fsl_sai_set_dai_tdm_slot,
635 	.hw_params	= fsl_sai_hw_params,
636 	.hw_free	= fsl_sai_hw_free,
637 	.trigger	= fsl_sai_trigger,
638 	.startup	= fsl_sai_startup,
639 	.shutdown	= fsl_sai_shutdown,
640 };
641 
642 static int fsl_sai_dai_probe(struct snd_soc_dai *cpu_dai)
643 {
644 	struct fsl_sai *sai = dev_get_drvdata(cpu_dai->dev);
645 
646 	/* Software Reset for both Tx and Rx */
647 	regmap_write(sai->regmap, FSL_SAI_TCSR, FSL_SAI_CSR_SR);
648 	regmap_write(sai->regmap, FSL_SAI_RCSR, FSL_SAI_CSR_SR);
649 	/* Clear SR bit to finish the reset */
650 	regmap_write(sai->regmap, FSL_SAI_TCSR, 0);
651 	regmap_write(sai->regmap, FSL_SAI_RCSR, 0);
652 
653 	regmap_update_bits(sai->regmap, FSL_SAI_TCR1, FSL_SAI_CR1_RFW_MASK,
654 			   FSL_SAI_MAXBURST_TX * 2);
655 	regmap_update_bits(sai->regmap, FSL_SAI_RCR1, FSL_SAI_CR1_RFW_MASK,
656 			   FSL_SAI_MAXBURST_RX - 1);
657 
658 	snd_soc_dai_init_dma_data(cpu_dai, &sai->dma_params_tx,
659 				&sai->dma_params_rx);
660 
661 	snd_soc_dai_set_drvdata(cpu_dai, sai);
662 
663 	return 0;
664 }
665 
666 static struct snd_soc_dai_driver fsl_sai_dai = {
667 	.probe = fsl_sai_dai_probe,
668 	.playback = {
669 		.stream_name = "CPU-Playback",
670 		.channels_min = 1,
671 		.channels_max = 2,
672 		.rate_min = 8000,
673 		.rate_max = 192000,
674 		.rates = SNDRV_PCM_RATE_KNOT,
675 		.formats = FSL_SAI_FORMATS,
676 	},
677 	.capture = {
678 		.stream_name = "CPU-Capture",
679 		.channels_min = 1,
680 		.channels_max = 2,
681 		.rate_min = 8000,
682 		.rate_max = 192000,
683 		.rates = SNDRV_PCM_RATE_KNOT,
684 		.formats = FSL_SAI_FORMATS,
685 	},
686 	.ops = &fsl_sai_pcm_dai_ops,
687 };
688 
689 static const struct snd_soc_component_driver fsl_component = {
690 	.name           = "fsl-sai",
691 };
692 
693 static struct reg_default fsl_sai_reg_defaults[] = {
694 	{FSL_SAI_TCR1, 0},
695 	{FSL_SAI_TCR2, 0},
696 	{FSL_SAI_TCR3, 0},
697 	{FSL_SAI_TCR4, 0},
698 	{FSL_SAI_TCR5, 0},
699 	{FSL_SAI_TDR,  0},
700 	{FSL_SAI_TMR,  0},
701 	{FSL_SAI_RCR1, 0},
702 	{FSL_SAI_RCR2, 0},
703 	{FSL_SAI_RCR3, 0},
704 	{FSL_SAI_RCR4, 0},
705 	{FSL_SAI_RCR5, 0},
706 	{FSL_SAI_RMR,  0},
707 };
708 
709 static bool fsl_sai_readable_reg(struct device *dev, unsigned int reg)
710 {
711 	switch (reg) {
712 	case FSL_SAI_TCSR:
713 	case FSL_SAI_TCR1:
714 	case FSL_SAI_TCR2:
715 	case FSL_SAI_TCR3:
716 	case FSL_SAI_TCR4:
717 	case FSL_SAI_TCR5:
718 	case FSL_SAI_TFR:
719 	case FSL_SAI_TMR:
720 	case FSL_SAI_RCSR:
721 	case FSL_SAI_RCR1:
722 	case FSL_SAI_RCR2:
723 	case FSL_SAI_RCR3:
724 	case FSL_SAI_RCR4:
725 	case FSL_SAI_RCR5:
726 	case FSL_SAI_RDR:
727 	case FSL_SAI_RFR:
728 	case FSL_SAI_RMR:
729 		return true;
730 	default:
731 		return false;
732 	}
733 }
734 
735 static bool fsl_sai_volatile_reg(struct device *dev, unsigned int reg)
736 {
737 	switch (reg) {
738 	case FSL_SAI_TCSR:
739 	case FSL_SAI_RCSR:
740 	case FSL_SAI_TFR:
741 	case FSL_SAI_RFR:
742 	case FSL_SAI_RDR:
743 		return true;
744 	default:
745 		return false;
746 	}
747 }
748 
749 static bool fsl_sai_writeable_reg(struct device *dev, unsigned int reg)
750 {
751 	switch (reg) {
752 	case FSL_SAI_TCSR:
753 	case FSL_SAI_TCR1:
754 	case FSL_SAI_TCR2:
755 	case FSL_SAI_TCR3:
756 	case FSL_SAI_TCR4:
757 	case FSL_SAI_TCR5:
758 	case FSL_SAI_TDR:
759 	case FSL_SAI_TMR:
760 	case FSL_SAI_RCSR:
761 	case FSL_SAI_RCR1:
762 	case FSL_SAI_RCR2:
763 	case FSL_SAI_RCR3:
764 	case FSL_SAI_RCR4:
765 	case FSL_SAI_RCR5:
766 	case FSL_SAI_RMR:
767 		return true;
768 	default:
769 		return false;
770 	}
771 }
772 
773 static const struct regmap_config fsl_sai_regmap_config = {
774 	.reg_bits = 32,
775 	.reg_stride = 4,
776 	.val_bits = 32,
777 
778 	.max_register = FSL_SAI_RMR,
779 	.reg_defaults = fsl_sai_reg_defaults,
780 	.num_reg_defaults = ARRAY_SIZE(fsl_sai_reg_defaults),
781 	.readable_reg = fsl_sai_readable_reg,
782 	.volatile_reg = fsl_sai_volatile_reg,
783 	.writeable_reg = fsl_sai_writeable_reg,
784 	.cache_type = REGCACHE_FLAT,
785 };
786 
787 static int fsl_sai_probe(struct platform_device *pdev)
788 {
789 	struct device_node *np = pdev->dev.of_node;
790 	struct fsl_sai *sai;
791 	struct regmap *gpr;
792 	struct resource *res;
793 	void __iomem *base;
794 	char tmp[8];
795 	int irq, ret, i;
796 	int index;
797 
798 	sai = devm_kzalloc(&pdev->dev, sizeof(*sai), GFP_KERNEL);
799 	if (!sai)
800 		return -ENOMEM;
801 
802 	sai->pdev = pdev;
803 
804 	if (of_device_is_compatible(pdev->dev.of_node, "fsl,imx6sx-sai") ||
805 	    of_device_is_compatible(pdev->dev.of_node, "fsl,imx6ul-sai"))
806 		sai->sai_on_imx = true;
807 
808 	sai->is_lsb_first = of_property_read_bool(np, "lsb-first");
809 
810 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
811 	base = devm_ioremap_resource(&pdev->dev, res);
812 	if (IS_ERR(base))
813 		return PTR_ERR(base);
814 
815 	sai->regmap = devm_regmap_init_mmio_clk(&pdev->dev,
816 			"bus", base, &fsl_sai_regmap_config);
817 
818 	/* Compatible with old DTB cases */
819 	if (IS_ERR(sai->regmap))
820 		sai->regmap = devm_regmap_init_mmio_clk(&pdev->dev,
821 				"sai", base, &fsl_sai_regmap_config);
822 	if (IS_ERR(sai->regmap)) {
823 		dev_err(&pdev->dev, "regmap init failed\n");
824 		return PTR_ERR(sai->regmap);
825 	}
826 
827 	/* No error out for old DTB cases but only mark the clock NULL */
828 	sai->bus_clk = devm_clk_get(&pdev->dev, "bus");
829 	if (IS_ERR(sai->bus_clk)) {
830 		dev_err(&pdev->dev, "failed to get bus clock: %ld\n",
831 				PTR_ERR(sai->bus_clk));
832 		sai->bus_clk = NULL;
833 	}
834 
835 	sai->mclk_clk[0] = sai->bus_clk;
836 	for (i = 1; i < FSL_SAI_MCLK_MAX; i++) {
837 		sprintf(tmp, "mclk%d", i);
838 		sai->mclk_clk[i] = devm_clk_get(&pdev->dev, tmp);
839 		if (IS_ERR(sai->mclk_clk[i])) {
840 			dev_err(&pdev->dev, "failed to get mclk%d clock: %ld\n",
841 					i + 1, PTR_ERR(sai->mclk_clk[i]));
842 			sai->mclk_clk[i] = NULL;
843 		}
844 	}
845 
846 	irq = platform_get_irq(pdev, 0);
847 	if (irq < 0) {
848 		dev_err(&pdev->dev, "no irq for node %s\n", pdev->name);
849 		return irq;
850 	}
851 
852 	ret = devm_request_irq(&pdev->dev, irq, fsl_sai_isr, 0, np->name, sai);
853 	if (ret) {
854 		dev_err(&pdev->dev, "failed to claim irq %u\n", irq);
855 		return ret;
856 	}
857 
858 	/* Sync Tx with Rx as default by following old DT binding */
859 	sai->synchronous[RX] = true;
860 	sai->synchronous[TX] = false;
861 	fsl_sai_dai.symmetric_rates = 1;
862 	fsl_sai_dai.symmetric_channels = 1;
863 	fsl_sai_dai.symmetric_samplebits = 1;
864 
865 	if (of_find_property(np, "fsl,sai-synchronous-rx", NULL) &&
866 	    of_find_property(np, "fsl,sai-asynchronous", NULL)) {
867 		/* error out if both synchronous and asynchronous are present */
868 		dev_err(&pdev->dev, "invalid binding for synchronous mode\n");
869 		return -EINVAL;
870 	}
871 
872 	if (of_find_property(np, "fsl,sai-synchronous-rx", NULL)) {
873 		/* Sync Rx with Tx */
874 		sai->synchronous[RX] = false;
875 		sai->synchronous[TX] = true;
876 	} else if (of_find_property(np, "fsl,sai-asynchronous", NULL)) {
877 		/* Discard all settings for asynchronous mode */
878 		sai->synchronous[RX] = false;
879 		sai->synchronous[TX] = false;
880 		fsl_sai_dai.symmetric_rates = 0;
881 		fsl_sai_dai.symmetric_channels = 0;
882 		fsl_sai_dai.symmetric_samplebits = 0;
883 	}
884 
885 	if (of_find_property(np, "fsl,sai-mclk-direction-output", NULL) &&
886 	    of_device_is_compatible(pdev->dev.of_node, "fsl,imx6ul-sai")) {
887 		gpr = syscon_regmap_lookup_by_compatible("fsl,imx6ul-iomuxc-gpr");
888 		if (IS_ERR(gpr)) {
889 			dev_err(&pdev->dev, "cannot find iomuxc registers\n");
890 			return PTR_ERR(gpr);
891 		}
892 
893 		index = of_alias_get_id(np, "sai");
894 		if (index < 0)
895 			return index;
896 
897 		regmap_update_bits(gpr, IOMUXC_GPR1, MCLK_DIR(index),
898 				   MCLK_DIR(index));
899 	}
900 
901 	sai->dma_params_rx.addr = res->start + FSL_SAI_RDR;
902 	sai->dma_params_tx.addr = res->start + FSL_SAI_TDR;
903 	sai->dma_params_rx.maxburst = FSL_SAI_MAXBURST_RX;
904 	sai->dma_params_tx.maxburst = FSL_SAI_MAXBURST_TX;
905 
906 	platform_set_drvdata(pdev, sai);
907 
908 	ret = devm_snd_soc_register_component(&pdev->dev, &fsl_component,
909 			&fsl_sai_dai, 1);
910 	if (ret)
911 		return ret;
912 
913 	if (sai->sai_on_imx)
914 		return imx_pcm_dma_init(pdev, IMX_SAI_DMABUF_SIZE);
915 	else
916 		return devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
917 }
918 
919 static const struct of_device_id fsl_sai_ids[] = {
920 	{ .compatible = "fsl,vf610-sai", },
921 	{ .compatible = "fsl,imx6sx-sai", },
922 	{ .compatible = "fsl,imx6ul-sai", },
923 	{ /* sentinel */ }
924 };
925 MODULE_DEVICE_TABLE(of, fsl_sai_ids);
926 
927 #ifdef CONFIG_PM_SLEEP
928 static int fsl_sai_suspend(struct device *dev)
929 {
930 	struct fsl_sai *sai = dev_get_drvdata(dev);
931 
932 	regcache_cache_only(sai->regmap, true);
933 	regcache_mark_dirty(sai->regmap);
934 
935 	return 0;
936 }
937 
938 static int fsl_sai_resume(struct device *dev)
939 {
940 	struct fsl_sai *sai = dev_get_drvdata(dev);
941 
942 	regcache_cache_only(sai->regmap, false);
943 	regmap_write(sai->regmap, FSL_SAI_TCSR, FSL_SAI_CSR_SR);
944 	regmap_write(sai->regmap, FSL_SAI_RCSR, FSL_SAI_CSR_SR);
945 	usleep_range(1000, 2000);
946 	regmap_write(sai->regmap, FSL_SAI_TCSR, 0);
947 	regmap_write(sai->regmap, FSL_SAI_RCSR, 0);
948 	return regcache_sync(sai->regmap);
949 }
950 #endif /* CONFIG_PM_SLEEP */
951 
952 static const struct dev_pm_ops fsl_sai_pm_ops = {
953 	SET_SYSTEM_SLEEP_PM_OPS(fsl_sai_suspend, fsl_sai_resume)
954 };
955 
956 static struct platform_driver fsl_sai_driver = {
957 	.probe = fsl_sai_probe,
958 	.driver = {
959 		.name = "fsl-sai",
960 		.pm = &fsl_sai_pm_ops,
961 		.of_match_table = fsl_sai_ids,
962 	},
963 };
964 module_platform_driver(fsl_sai_driver);
965 
966 MODULE_DESCRIPTION("Freescale Soc SAI Interface");
967 MODULE_AUTHOR("Xiubo Li, <Li.Xiubo@freescale.com>");
968 MODULE_ALIAS("platform:fsl-sai");
969 MODULE_LICENSE("GPL");
970