xref: /openbmc/linux/sound/soc/fsl/fsl_sai.c (revision 8b030a57)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Freescale ALSA SoC Digital Audio Interface (SAI) driver.
4 //
5 // Copyright 2012-2015 Freescale Semiconductor, Inc.
6 
7 #include <linux/clk.h>
8 #include <linux/delay.h>
9 #include <linux/dmaengine.h>
10 #include <linux/module.h>
11 #include <linux/of_address.h>
12 #include <linux/regmap.h>
13 #include <linux/slab.h>
14 #include <linux/time.h>
15 #include <sound/core.h>
16 #include <sound/dmaengine_pcm.h>
17 #include <sound/pcm_params.h>
18 #include <linux/mfd/syscon.h>
19 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
20 
21 #include "fsl_sai.h"
22 #include "imx-pcm.h"
23 
24 #define FSL_SAI_FLAGS (FSL_SAI_CSR_SEIE |\
25 		       FSL_SAI_CSR_FEIE)
26 
27 static const unsigned int fsl_sai_rates[] = {
28 	8000, 11025, 12000, 16000, 22050,
29 	24000, 32000, 44100, 48000, 64000,
30 	88200, 96000, 176400, 192000
31 };
32 
33 static const struct snd_pcm_hw_constraint_list fsl_sai_rate_constraints = {
34 	.count = ARRAY_SIZE(fsl_sai_rates),
35 	.list = fsl_sai_rates,
36 };
37 
38 static irqreturn_t fsl_sai_isr(int irq, void *devid)
39 {
40 	struct fsl_sai *sai = (struct fsl_sai *)devid;
41 	struct device *dev = &sai->pdev->dev;
42 	u32 flags, xcsr, mask;
43 	bool irq_none = true;
44 
45 	/*
46 	 * Both IRQ status bits and IRQ mask bits are in the xCSR but
47 	 * different shifts. And we here create a mask only for those
48 	 * IRQs that we activated.
49 	 */
50 	mask = (FSL_SAI_FLAGS >> FSL_SAI_CSR_xIE_SHIFT) << FSL_SAI_CSR_xF_SHIFT;
51 
52 	/* Tx IRQ */
53 	regmap_read(sai->regmap, FSL_SAI_TCSR, &xcsr);
54 	flags = xcsr & mask;
55 
56 	if (flags)
57 		irq_none = false;
58 	else
59 		goto irq_rx;
60 
61 	if (flags & FSL_SAI_CSR_WSF)
62 		dev_dbg(dev, "isr: Start of Tx word detected\n");
63 
64 	if (flags & FSL_SAI_CSR_SEF)
65 		dev_dbg(dev, "isr: Tx Frame sync error detected\n");
66 
67 	if (flags & FSL_SAI_CSR_FEF) {
68 		dev_dbg(dev, "isr: Transmit underrun detected\n");
69 		/* FIFO reset for safety */
70 		xcsr |= FSL_SAI_CSR_FR;
71 	}
72 
73 	if (flags & FSL_SAI_CSR_FWF)
74 		dev_dbg(dev, "isr: Enabled transmit FIFO is empty\n");
75 
76 	if (flags & FSL_SAI_CSR_FRF)
77 		dev_dbg(dev, "isr: Transmit FIFO watermark has been reached\n");
78 
79 	flags &= FSL_SAI_CSR_xF_W_MASK;
80 	xcsr &= ~FSL_SAI_CSR_xF_MASK;
81 
82 	if (flags)
83 		regmap_write(sai->regmap, FSL_SAI_TCSR, flags | xcsr);
84 
85 irq_rx:
86 	/* Rx IRQ */
87 	regmap_read(sai->regmap, FSL_SAI_RCSR, &xcsr);
88 	flags = xcsr & mask;
89 
90 	if (flags)
91 		irq_none = false;
92 	else
93 		goto out;
94 
95 	if (flags & FSL_SAI_CSR_WSF)
96 		dev_dbg(dev, "isr: Start of Rx word detected\n");
97 
98 	if (flags & FSL_SAI_CSR_SEF)
99 		dev_dbg(dev, "isr: Rx Frame sync error detected\n");
100 
101 	if (flags & FSL_SAI_CSR_FEF) {
102 		dev_dbg(dev, "isr: Receive overflow detected\n");
103 		/* FIFO reset for safety */
104 		xcsr |= FSL_SAI_CSR_FR;
105 	}
106 
107 	if (flags & FSL_SAI_CSR_FWF)
108 		dev_dbg(dev, "isr: Enabled receive FIFO is full\n");
109 
110 	if (flags & FSL_SAI_CSR_FRF)
111 		dev_dbg(dev, "isr: Receive FIFO watermark has been reached\n");
112 
113 	flags &= FSL_SAI_CSR_xF_W_MASK;
114 	xcsr &= ~FSL_SAI_CSR_xF_MASK;
115 
116 	if (flags)
117 		regmap_write(sai->regmap, FSL_SAI_RCSR, flags | xcsr);
118 
119 out:
120 	if (irq_none)
121 		return IRQ_NONE;
122 	else
123 		return IRQ_HANDLED;
124 }
125 
126 static int fsl_sai_set_dai_tdm_slot(struct snd_soc_dai *cpu_dai, u32 tx_mask,
127 				u32 rx_mask, int slots, int slot_width)
128 {
129 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
130 
131 	sai->slots = slots;
132 	sai->slot_width = slot_width;
133 
134 	return 0;
135 }
136 
137 static int fsl_sai_set_dai_sysclk_tr(struct snd_soc_dai *cpu_dai,
138 		int clk_id, unsigned int freq, int fsl_dir)
139 {
140 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
141 	bool tx = fsl_dir == FSL_FMT_TRANSMITTER;
142 	u32 val_cr2 = 0;
143 
144 	switch (clk_id) {
145 	case FSL_SAI_CLK_BUS:
146 		val_cr2 |= FSL_SAI_CR2_MSEL_BUS;
147 		break;
148 	case FSL_SAI_CLK_MAST1:
149 		val_cr2 |= FSL_SAI_CR2_MSEL_MCLK1;
150 		break;
151 	case FSL_SAI_CLK_MAST2:
152 		val_cr2 |= FSL_SAI_CR2_MSEL_MCLK2;
153 		break;
154 	case FSL_SAI_CLK_MAST3:
155 		val_cr2 |= FSL_SAI_CR2_MSEL_MCLK3;
156 		break;
157 	default:
158 		return -EINVAL;
159 	}
160 
161 	regmap_update_bits(sai->regmap, FSL_SAI_xCR2(tx),
162 			   FSL_SAI_CR2_MSEL_MASK, val_cr2);
163 
164 	return 0;
165 }
166 
167 static int fsl_sai_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
168 		int clk_id, unsigned int freq, int dir)
169 {
170 	int ret;
171 
172 	if (dir == SND_SOC_CLOCK_IN)
173 		return 0;
174 
175 	ret = fsl_sai_set_dai_sysclk_tr(cpu_dai, clk_id, freq,
176 					FSL_FMT_TRANSMITTER);
177 	if (ret) {
178 		dev_err(cpu_dai->dev, "Cannot set tx sysclk: %d\n", ret);
179 		return ret;
180 	}
181 
182 	ret = fsl_sai_set_dai_sysclk_tr(cpu_dai, clk_id, freq,
183 					FSL_FMT_RECEIVER);
184 	if (ret)
185 		dev_err(cpu_dai->dev, "Cannot set rx sysclk: %d\n", ret);
186 
187 	return ret;
188 }
189 
190 static int fsl_sai_set_dai_fmt_tr(struct snd_soc_dai *cpu_dai,
191 				unsigned int fmt, int fsl_dir)
192 {
193 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
194 	bool tx = fsl_dir == FSL_FMT_TRANSMITTER;
195 	u32 val_cr2 = 0, val_cr4 = 0;
196 
197 	if (!sai->is_lsb_first)
198 		val_cr4 |= FSL_SAI_CR4_MF;
199 
200 	/* DAI mode */
201 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
202 	case SND_SOC_DAIFMT_I2S:
203 		/*
204 		 * Frame low, 1clk before data, one word length for frame sync,
205 		 * frame sync starts one serial clock cycle earlier,
206 		 * that is, together with the last bit of the previous
207 		 * data word.
208 		 */
209 		val_cr2 |= FSL_SAI_CR2_BCP;
210 		val_cr4 |= FSL_SAI_CR4_FSE | FSL_SAI_CR4_FSP;
211 		break;
212 	case SND_SOC_DAIFMT_LEFT_J:
213 		/*
214 		 * Frame high, one word length for frame sync,
215 		 * frame sync asserts with the first bit of the frame.
216 		 */
217 		val_cr2 |= FSL_SAI_CR2_BCP;
218 		break;
219 	case SND_SOC_DAIFMT_DSP_A:
220 		/*
221 		 * Frame high, 1clk before data, one bit for frame sync,
222 		 * frame sync starts one serial clock cycle earlier,
223 		 * that is, together with the last bit of the previous
224 		 * data word.
225 		 */
226 		val_cr2 |= FSL_SAI_CR2_BCP;
227 		val_cr4 |= FSL_SAI_CR4_FSE;
228 		sai->is_dsp_mode = true;
229 		break;
230 	case SND_SOC_DAIFMT_DSP_B:
231 		/*
232 		 * Frame high, one bit for frame sync,
233 		 * frame sync asserts with the first bit of the frame.
234 		 */
235 		val_cr2 |= FSL_SAI_CR2_BCP;
236 		sai->is_dsp_mode = true;
237 		break;
238 	case SND_SOC_DAIFMT_RIGHT_J:
239 		/* To be done */
240 	default:
241 		return -EINVAL;
242 	}
243 
244 	/* DAI clock inversion */
245 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
246 	case SND_SOC_DAIFMT_IB_IF:
247 		/* Invert both clocks */
248 		val_cr2 ^= FSL_SAI_CR2_BCP;
249 		val_cr4 ^= FSL_SAI_CR4_FSP;
250 		break;
251 	case SND_SOC_DAIFMT_IB_NF:
252 		/* Invert bit clock */
253 		val_cr2 ^= FSL_SAI_CR2_BCP;
254 		break;
255 	case SND_SOC_DAIFMT_NB_IF:
256 		/* Invert frame clock */
257 		val_cr4 ^= FSL_SAI_CR4_FSP;
258 		break;
259 	case SND_SOC_DAIFMT_NB_NF:
260 		/* Nothing to do for both normal cases */
261 		break;
262 	default:
263 		return -EINVAL;
264 	}
265 
266 	/* DAI clock master masks */
267 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
268 	case SND_SOC_DAIFMT_CBS_CFS:
269 		val_cr2 |= FSL_SAI_CR2_BCD_MSTR;
270 		val_cr4 |= FSL_SAI_CR4_FSD_MSTR;
271 		break;
272 	case SND_SOC_DAIFMT_CBM_CFM:
273 		sai->is_slave_mode = true;
274 		break;
275 	case SND_SOC_DAIFMT_CBS_CFM:
276 		val_cr2 |= FSL_SAI_CR2_BCD_MSTR;
277 		break;
278 	case SND_SOC_DAIFMT_CBM_CFS:
279 		val_cr4 |= FSL_SAI_CR4_FSD_MSTR;
280 		sai->is_slave_mode = true;
281 		break;
282 	default:
283 		return -EINVAL;
284 	}
285 
286 	regmap_update_bits(sai->regmap, FSL_SAI_xCR2(tx),
287 			   FSL_SAI_CR2_BCP | FSL_SAI_CR2_BCD_MSTR, val_cr2);
288 	regmap_update_bits(sai->regmap, FSL_SAI_xCR4(tx),
289 			   FSL_SAI_CR4_MF | FSL_SAI_CR4_FSE |
290 			   FSL_SAI_CR4_FSP | FSL_SAI_CR4_FSD_MSTR, val_cr4);
291 
292 	return 0;
293 }
294 
295 static int fsl_sai_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
296 {
297 	int ret;
298 
299 	ret = fsl_sai_set_dai_fmt_tr(cpu_dai, fmt, FSL_FMT_TRANSMITTER);
300 	if (ret) {
301 		dev_err(cpu_dai->dev, "Cannot set tx format: %d\n", ret);
302 		return ret;
303 	}
304 
305 	ret = fsl_sai_set_dai_fmt_tr(cpu_dai, fmt, FSL_FMT_RECEIVER);
306 	if (ret)
307 		dev_err(cpu_dai->dev, "Cannot set rx format: %d\n", ret);
308 
309 	return ret;
310 }
311 
312 static int fsl_sai_set_bclk(struct snd_soc_dai *dai, bool tx, u32 freq)
313 {
314 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(dai);
315 	unsigned long clk_rate;
316 	u32 savediv = 0, ratio, savesub = freq;
317 	u32 id;
318 	int ret = 0;
319 
320 	/* Don't apply to slave mode */
321 	if (sai->is_slave_mode)
322 		return 0;
323 
324 	for (id = 0; id < FSL_SAI_MCLK_MAX; id++) {
325 		clk_rate = clk_get_rate(sai->mclk_clk[id]);
326 		if (!clk_rate)
327 			continue;
328 
329 		ratio = clk_rate / freq;
330 
331 		ret = clk_rate - ratio * freq;
332 
333 		/*
334 		 * Drop the source that can not be
335 		 * divided into the required rate.
336 		 */
337 		if (ret != 0 && clk_rate / ret < 1000)
338 			continue;
339 
340 		dev_dbg(dai->dev,
341 			"ratio %d for freq %dHz based on clock %ldHz\n",
342 			ratio, freq, clk_rate);
343 
344 		if (ratio % 2 == 0 && ratio >= 2 && ratio <= 512)
345 			ratio /= 2;
346 		else
347 			continue;
348 
349 		if (ret < savesub) {
350 			savediv = ratio;
351 			sai->mclk_id[tx] = id;
352 			savesub = ret;
353 		}
354 
355 		if (ret == 0)
356 			break;
357 	}
358 
359 	if (savediv == 0) {
360 		dev_err(dai->dev, "failed to derive required %cx rate: %d\n",
361 				tx ? 'T' : 'R', freq);
362 		return -EINVAL;
363 	}
364 
365 	/*
366 	 * 1) For Asynchronous mode, we must set RCR2 register for capture, and
367 	 *    set TCR2 register for playback.
368 	 * 2) For Tx sync with Rx clock, we must set RCR2 register for playback
369 	 *    and capture.
370 	 * 3) For Rx sync with Tx clock, we must set TCR2 register for playback
371 	 *    and capture.
372 	 * 4) For Tx and Rx are both Synchronous with another SAI, we just
373 	 *    ignore it.
374 	 */
375 	if ((sai->synchronous[TX] && !sai->synchronous[RX]) ||
376 	    (!tx && !sai->synchronous[RX])) {
377 		regmap_update_bits(sai->regmap, FSL_SAI_RCR2,
378 				   FSL_SAI_CR2_MSEL_MASK,
379 				   FSL_SAI_CR2_MSEL(sai->mclk_id[tx]));
380 		regmap_update_bits(sai->regmap, FSL_SAI_RCR2,
381 				   FSL_SAI_CR2_DIV_MASK, savediv - 1);
382 	} else if ((sai->synchronous[RX] && !sai->synchronous[TX]) ||
383 		   (tx && !sai->synchronous[TX])) {
384 		regmap_update_bits(sai->regmap, FSL_SAI_TCR2,
385 				   FSL_SAI_CR2_MSEL_MASK,
386 				   FSL_SAI_CR2_MSEL(sai->mclk_id[tx]));
387 		regmap_update_bits(sai->regmap, FSL_SAI_TCR2,
388 				   FSL_SAI_CR2_DIV_MASK, savediv - 1);
389 	}
390 
391 	dev_dbg(dai->dev, "best fit: clock id=%d, div=%d, deviation =%d\n",
392 			sai->mclk_id[tx], savediv, savesub);
393 
394 	return 0;
395 }
396 
397 static int fsl_sai_hw_params(struct snd_pcm_substream *substream,
398 		struct snd_pcm_hw_params *params,
399 		struct snd_soc_dai *cpu_dai)
400 {
401 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
402 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
403 	unsigned int channels = params_channels(params);
404 	u32 word_width = params_width(params);
405 	u32 val_cr4 = 0, val_cr5 = 0;
406 	u32 slots = (channels == 1) ? 2 : channels;
407 	u32 slot_width = word_width;
408 	int ret;
409 
410 	if (sai->slots)
411 		slots = sai->slots;
412 
413 	if (sai->slot_width)
414 		slot_width = sai->slot_width;
415 
416 	if (!sai->is_slave_mode) {
417 		ret = fsl_sai_set_bclk(cpu_dai, tx,
418 				slots * slot_width * params_rate(params));
419 		if (ret)
420 			return ret;
421 
422 		/* Do not enable the clock if it is already enabled */
423 		if (!(sai->mclk_streams & BIT(substream->stream))) {
424 			ret = clk_prepare_enable(sai->mclk_clk[sai->mclk_id[tx]]);
425 			if (ret)
426 				return ret;
427 
428 			sai->mclk_streams |= BIT(substream->stream);
429 		}
430 	}
431 
432 	if (!sai->is_dsp_mode)
433 		val_cr4 |= FSL_SAI_CR4_SYWD(slot_width);
434 
435 	val_cr5 |= FSL_SAI_CR5_WNW(slot_width);
436 	val_cr5 |= FSL_SAI_CR5_W0W(slot_width);
437 
438 	if (sai->is_lsb_first)
439 		val_cr5 |= FSL_SAI_CR5_FBT(0);
440 	else
441 		val_cr5 |= FSL_SAI_CR5_FBT(word_width - 1);
442 
443 	val_cr4 |= FSL_SAI_CR4_FRSZ(slots);
444 
445 	/*
446 	 * For SAI master mode, when Tx(Rx) sync with Rx(Tx) clock, Rx(Tx) will
447 	 * generate bclk and frame clock for Tx(Rx), we should set RCR4(TCR4),
448 	 * RCR5(TCR5) and RMR(TMR) for playback(capture), or there will be sync
449 	 * error.
450 	 */
451 
452 	if (!sai->is_slave_mode) {
453 		if (!sai->synchronous[TX] && sai->synchronous[RX] && !tx) {
454 			regmap_update_bits(sai->regmap, FSL_SAI_TCR4,
455 				FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
456 				val_cr4);
457 			regmap_update_bits(sai->regmap, FSL_SAI_TCR5,
458 				FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
459 				FSL_SAI_CR5_FBT_MASK, val_cr5);
460 			regmap_write(sai->regmap, FSL_SAI_TMR,
461 				~0UL - ((1 << channels) - 1));
462 		} else if (!sai->synchronous[RX] && sai->synchronous[TX] && tx) {
463 			regmap_update_bits(sai->regmap, FSL_SAI_RCR4,
464 				FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
465 				val_cr4);
466 			regmap_update_bits(sai->regmap, FSL_SAI_RCR5,
467 				FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
468 				FSL_SAI_CR5_FBT_MASK, val_cr5);
469 			regmap_write(sai->regmap, FSL_SAI_RMR,
470 				~0UL - ((1 << channels) - 1));
471 		}
472 	}
473 
474 	regmap_update_bits(sai->regmap, FSL_SAI_xCR4(tx),
475 			   FSL_SAI_CR4_SYWD_MASK | FSL_SAI_CR4_FRSZ_MASK,
476 			   val_cr4);
477 	regmap_update_bits(sai->regmap, FSL_SAI_xCR5(tx),
478 			   FSL_SAI_CR5_WNW_MASK | FSL_SAI_CR5_W0W_MASK |
479 			   FSL_SAI_CR5_FBT_MASK, val_cr5);
480 	regmap_write(sai->regmap, FSL_SAI_xMR(tx), ~0UL - ((1 << channels) - 1));
481 
482 	return 0;
483 }
484 
485 static int fsl_sai_hw_free(struct snd_pcm_substream *substream,
486 		struct snd_soc_dai *cpu_dai)
487 {
488 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
489 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
490 
491 	if (!sai->is_slave_mode &&
492 			sai->mclk_streams & BIT(substream->stream)) {
493 		clk_disable_unprepare(sai->mclk_clk[sai->mclk_id[tx]]);
494 		sai->mclk_streams &= ~BIT(substream->stream);
495 	}
496 
497 	return 0;
498 }
499 
500 
501 static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd,
502 		struct snd_soc_dai *cpu_dai)
503 {
504 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
505 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
506 	u32 xcsr, count = 100;
507 
508 	/*
509 	 * Asynchronous mode: Clear SYNC for both Tx and Rx.
510 	 * Rx sync with Tx clocks: Clear SYNC for Tx, set it for Rx.
511 	 * Tx sync with Rx clocks: Clear SYNC for Rx, set it for Tx.
512 	 */
513 	regmap_update_bits(sai->regmap, FSL_SAI_TCR2, FSL_SAI_CR2_SYNC,
514 		           sai->synchronous[TX] ? FSL_SAI_CR2_SYNC : 0);
515 	regmap_update_bits(sai->regmap, FSL_SAI_RCR2, FSL_SAI_CR2_SYNC,
516 			   sai->synchronous[RX] ? FSL_SAI_CR2_SYNC : 0);
517 
518 	/*
519 	 * It is recommended that the transmitter is the last enabled
520 	 * and the first disabled.
521 	 */
522 	switch (cmd) {
523 	case SNDRV_PCM_TRIGGER_START:
524 	case SNDRV_PCM_TRIGGER_RESUME:
525 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
526 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx),
527 				   FSL_SAI_CSR_FRDE, FSL_SAI_CSR_FRDE);
528 
529 		regmap_update_bits(sai->regmap, FSL_SAI_RCSR,
530 				   FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
531 		regmap_update_bits(sai->regmap, FSL_SAI_TCSR,
532 				   FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE);
533 
534 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx),
535 				   FSL_SAI_CSR_xIE_MASK, FSL_SAI_FLAGS);
536 		break;
537 	case SNDRV_PCM_TRIGGER_STOP:
538 	case SNDRV_PCM_TRIGGER_SUSPEND:
539 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
540 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx),
541 				   FSL_SAI_CSR_FRDE, 0);
542 		regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx),
543 				   FSL_SAI_CSR_xIE_MASK, 0);
544 
545 		/* Check if the opposite FRDE is also disabled */
546 		regmap_read(sai->regmap, FSL_SAI_xCSR(!tx), &xcsr);
547 		if (!(xcsr & FSL_SAI_CSR_FRDE)) {
548 			/* Disable both directions and reset their FIFOs */
549 			regmap_update_bits(sai->regmap, FSL_SAI_TCSR,
550 					   FSL_SAI_CSR_TERE, 0);
551 			regmap_update_bits(sai->regmap, FSL_SAI_RCSR,
552 					   FSL_SAI_CSR_TERE, 0);
553 
554 			/* TERE will remain set till the end of current frame */
555 			do {
556 				udelay(10);
557 				regmap_read(sai->regmap, FSL_SAI_xCSR(tx), &xcsr);
558 			} while (--count && xcsr & FSL_SAI_CSR_TERE);
559 
560 			regmap_update_bits(sai->regmap, FSL_SAI_TCSR,
561 					   FSL_SAI_CSR_FR, FSL_SAI_CSR_FR);
562 			regmap_update_bits(sai->regmap, FSL_SAI_RCSR,
563 					   FSL_SAI_CSR_FR, FSL_SAI_CSR_FR);
564 
565 			/*
566 			 * For sai master mode, after several open/close sai,
567 			 * there will be no frame clock, and can't recover
568 			 * anymore. Add software reset to fix this issue.
569 			 * This is a hardware bug, and will be fix in the
570 			 * next sai version.
571 			 */
572 			if (!sai->is_slave_mode) {
573 				/* Software Reset for both Tx and Rx */
574 				regmap_write(sai->regmap,
575 					     FSL_SAI_TCSR, FSL_SAI_CSR_SR);
576 				regmap_write(sai->regmap,
577 					     FSL_SAI_RCSR, FSL_SAI_CSR_SR);
578 				/* Clear SR bit to finish the reset */
579 				regmap_write(sai->regmap, FSL_SAI_TCSR, 0);
580 				regmap_write(sai->regmap, FSL_SAI_RCSR, 0);
581 			}
582 		}
583 		break;
584 	default:
585 		return -EINVAL;
586 	}
587 
588 	return 0;
589 }
590 
591 static int fsl_sai_startup(struct snd_pcm_substream *substream,
592 		struct snd_soc_dai *cpu_dai)
593 {
594 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
595 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
596 	struct device *dev = &sai->pdev->dev;
597 	int ret;
598 
599 	ret = clk_prepare_enable(sai->bus_clk);
600 	if (ret) {
601 		dev_err(dev, "failed to enable bus clock: %d\n", ret);
602 		return ret;
603 	}
604 
605 	regmap_update_bits(sai->regmap, FSL_SAI_xCR3(tx), FSL_SAI_CR3_TRCE,
606 			   FSL_SAI_CR3_TRCE);
607 
608 	ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
609 			SNDRV_PCM_HW_PARAM_RATE, &fsl_sai_rate_constraints);
610 
611 	return ret;
612 }
613 
614 static void fsl_sai_shutdown(struct snd_pcm_substream *substream,
615 		struct snd_soc_dai *cpu_dai)
616 {
617 	struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai);
618 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
619 
620 	regmap_update_bits(sai->regmap, FSL_SAI_xCR3(tx), FSL_SAI_CR3_TRCE, 0);
621 
622 	clk_disable_unprepare(sai->bus_clk);
623 }
624 
625 static const struct snd_soc_dai_ops fsl_sai_pcm_dai_ops = {
626 	.set_sysclk	= fsl_sai_set_dai_sysclk,
627 	.set_fmt	= fsl_sai_set_dai_fmt,
628 	.set_tdm_slot	= fsl_sai_set_dai_tdm_slot,
629 	.hw_params	= fsl_sai_hw_params,
630 	.hw_free	= fsl_sai_hw_free,
631 	.trigger	= fsl_sai_trigger,
632 	.startup	= fsl_sai_startup,
633 	.shutdown	= fsl_sai_shutdown,
634 };
635 
636 static int fsl_sai_dai_probe(struct snd_soc_dai *cpu_dai)
637 {
638 	struct fsl_sai *sai = dev_get_drvdata(cpu_dai->dev);
639 
640 	/* Software Reset for both Tx and Rx */
641 	regmap_write(sai->regmap, FSL_SAI_TCSR, FSL_SAI_CSR_SR);
642 	regmap_write(sai->regmap, FSL_SAI_RCSR, FSL_SAI_CSR_SR);
643 	/* Clear SR bit to finish the reset */
644 	regmap_write(sai->regmap, FSL_SAI_TCSR, 0);
645 	regmap_write(sai->regmap, FSL_SAI_RCSR, 0);
646 
647 	regmap_update_bits(sai->regmap, FSL_SAI_TCR1, FSL_SAI_CR1_RFW_MASK,
648 			   FSL_SAI_MAXBURST_TX * 2);
649 	regmap_update_bits(sai->regmap, FSL_SAI_RCR1, FSL_SAI_CR1_RFW_MASK,
650 			   FSL_SAI_MAXBURST_RX - 1);
651 
652 	snd_soc_dai_init_dma_data(cpu_dai, &sai->dma_params_tx,
653 				&sai->dma_params_rx);
654 
655 	snd_soc_dai_set_drvdata(cpu_dai, sai);
656 
657 	return 0;
658 }
659 
660 static struct snd_soc_dai_driver fsl_sai_dai = {
661 	.probe = fsl_sai_dai_probe,
662 	.playback = {
663 		.stream_name = "CPU-Playback",
664 		.channels_min = 1,
665 		.channels_max = 32,
666 		.rate_min = 8000,
667 		.rate_max = 192000,
668 		.rates = SNDRV_PCM_RATE_KNOT,
669 		.formats = FSL_SAI_FORMATS,
670 	},
671 	.capture = {
672 		.stream_name = "CPU-Capture",
673 		.channels_min = 1,
674 		.channels_max = 32,
675 		.rate_min = 8000,
676 		.rate_max = 192000,
677 		.rates = SNDRV_PCM_RATE_KNOT,
678 		.formats = FSL_SAI_FORMATS,
679 	},
680 	.ops = &fsl_sai_pcm_dai_ops,
681 };
682 
683 static const struct snd_soc_component_driver fsl_component = {
684 	.name           = "fsl-sai",
685 };
686 
687 static struct reg_default fsl_sai_reg_defaults[] = {
688 	{FSL_SAI_TCR1, 0},
689 	{FSL_SAI_TCR2, 0},
690 	{FSL_SAI_TCR3, 0},
691 	{FSL_SAI_TCR4, 0},
692 	{FSL_SAI_TCR5, 0},
693 	{FSL_SAI_TDR,  0},
694 	{FSL_SAI_TMR,  0},
695 	{FSL_SAI_RCR1, 0},
696 	{FSL_SAI_RCR2, 0},
697 	{FSL_SAI_RCR3, 0},
698 	{FSL_SAI_RCR4, 0},
699 	{FSL_SAI_RCR5, 0},
700 	{FSL_SAI_RMR,  0},
701 };
702 
703 static bool fsl_sai_readable_reg(struct device *dev, unsigned int reg)
704 {
705 	switch (reg) {
706 	case FSL_SAI_TCSR:
707 	case FSL_SAI_TCR1:
708 	case FSL_SAI_TCR2:
709 	case FSL_SAI_TCR3:
710 	case FSL_SAI_TCR4:
711 	case FSL_SAI_TCR5:
712 	case FSL_SAI_TFR:
713 	case FSL_SAI_TMR:
714 	case FSL_SAI_RCSR:
715 	case FSL_SAI_RCR1:
716 	case FSL_SAI_RCR2:
717 	case FSL_SAI_RCR3:
718 	case FSL_SAI_RCR4:
719 	case FSL_SAI_RCR5:
720 	case FSL_SAI_RDR:
721 	case FSL_SAI_RFR:
722 	case FSL_SAI_RMR:
723 		return true;
724 	default:
725 		return false;
726 	}
727 }
728 
729 static bool fsl_sai_volatile_reg(struct device *dev, unsigned int reg)
730 {
731 	switch (reg) {
732 	case FSL_SAI_TCSR:
733 	case FSL_SAI_RCSR:
734 	case FSL_SAI_TFR:
735 	case FSL_SAI_RFR:
736 	case FSL_SAI_RDR:
737 		return true;
738 	default:
739 		return false;
740 	}
741 }
742 
743 static bool fsl_sai_writeable_reg(struct device *dev, unsigned int reg)
744 {
745 	switch (reg) {
746 	case FSL_SAI_TCSR:
747 	case FSL_SAI_TCR1:
748 	case FSL_SAI_TCR2:
749 	case FSL_SAI_TCR3:
750 	case FSL_SAI_TCR4:
751 	case FSL_SAI_TCR5:
752 	case FSL_SAI_TDR:
753 	case FSL_SAI_TMR:
754 	case FSL_SAI_RCSR:
755 	case FSL_SAI_RCR1:
756 	case FSL_SAI_RCR2:
757 	case FSL_SAI_RCR3:
758 	case FSL_SAI_RCR4:
759 	case FSL_SAI_RCR5:
760 	case FSL_SAI_RMR:
761 		return true;
762 	default:
763 		return false;
764 	}
765 }
766 
767 static const struct regmap_config fsl_sai_regmap_config = {
768 	.reg_bits = 32,
769 	.reg_stride = 4,
770 	.val_bits = 32,
771 
772 	.max_register = FSL_SAI_RMR,
773 	.reg_defaults = fsl_sai_reg_defaults,
774 	.num_reg_defaults = ARRAY_SIZE(fsl_sai_reg_defaults),
775 	.readable_reg = fsl_sai_readable_reg,
776 	.volatile_reg = fsl_sai_volatile_reg,
777 	.writeable_reg = fsl_sai_writeable_reg,
778 	.cache_type = REGCACHE_FLAT,
779 };
780 
781 static int fsl_sai_probe(struct platform_device *pdev)
782 {
783 	struct device_node *np = pdev->dev.of_node;
784 	struct fsl_sai *sai;
785 	struct regmap *gpr;
786 	struct resource *res;
787 	void __iomem *base;
788 	char tmp[8];
789 	int irq, ret, i;
790 	int index;
791 
792 	sai = devm_kzalloc(&pdev->dev, sizeof(*sai), GFP_KERNEL);
793 	if (!sai)
794 		return -ENOMEM;
795 
796 	sai->pdev = pdev;
797 
798 	if (of_device_is_compatible(np, "fsl,imx6sx-sai") ||
799 	    of_device_is_compatible(np, "fsl,imx6ul-sai"))
800 		sai->sai_on_imx = true;
801 
802 	sai->is_lsb_first = of_property_read_bool(np, "lsb-first");
803 
804 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
805 	base = devm_ioremap_resource(&pdev->dev, res);
806 	if (IS_ERR(base))
807 		return PTR_ERR(base);
808 
809 	sai->regmap = devm_regmap_init_mmio_clk(&pdev->dev,
810 			"bus", base, &fsl_sai_regmap_config);
811 
812 	/* Compatible with old DTB cases */
813 	if (IS_ERR(sai->regmap))
814 		sai->regmap = devm_regmap_init_mmio_clk(&pdev->dev,
815 				"sai", base, &fsl_sai_regmap_config);
816 	if (IS_ERR(sai->regmap)) {
817 		dev_err(&pdev->dev, "regmap init failed\n");
818 		return PTR_ERR(sai->regmap);
819 	}
820 
821 	/* No error out for old DTB cases but only mark the clock NULL */
822 	sai->bus_clk = devm_clk_get(&pdev->dev, "bus");
823 	if (IS_ERR(sai->bus_clk)) {
824 		dev_err(&pdev->dev, "failed to get bus clock: %ld\n",
825 				PTR_ERR(sai->bus_clk));
826 		sai->bus_clk = NULL;
827 	}
828 
829 	sai->mclk_clk[0] = sai->bus_clk;
830 	for (i = 1; i < FSL_SAI_MCLK_MAX; i++) {
831 		sprintf(tmp, "mclk%d", i);
832 		sai->mclk_clk[i] = devm_clk_get(&pdev->dev, tmp);
833 		if (IS_ERR(sai->mclk_clk[i])) {
834 			dev_err(&pdev->dev, "failed to get mclk%d clock: %ld\n",
835 					i + 1, PTR_ERR(sai->mclk_clk[i]));
836 			sai->mclk_clk[i] = NULL;
837 		}
838 	}
839 
840 	irq = platform_get_irq(pdev, 0);
841 	if (irq < 0) {
842 		dev_err(&pdev->dev, "no irq for node %s\n", pdev->name);
843 		return irq;
844 	}
845 
846 	ret = devm_request_irq(&pdev->dev, irq, fsl_sai_isr, 0, np->name, sai);
847 	if (ret) {
848 		dev_err(&pdev->dev, "failed to claim irq %u\n", irq);
849 		return ret;
850 	}
851 
852 	/* Sync Tx with Rx as default by following old DT binding */
853 	sai->synchronous[RX] = true;
854 	sai->synchronous[TX] = false;
855 	fsl_sai_dai.symmetric_rates = 1;
856 	fsl_sai_dai.symmetric_channels = 1;
857 	fsl_sai_dai.symmetric_samplebits = 1;
858 
859 	if (of_find_property(np, "fsl,sai-synchronous-rx", NULL) &&
860 	    of_find_property(np, "fsl,sai-asynchronous", NULL)) {
861 		/* error out if both synchronous and asynchronous are present */
862 		dev_err(&pdev->dev, "invalid binding for synchronous mode\n");
863 		return -EINVAL;
864 	}
865 
866 	if (of_find_property(np, "fsl,sai-synchronous-rx", NULL)) {
867 		/* Sync Rx with Tx */
868 		sai->synchronous[RX] = false;
869 		sai->synchronous[TX] = true;
870 	} else if (of_find_property(np, "fsl,sai-asynchronous", NULL)) {
871 		/* Discard all settings for asynchronous mode */
872 		sai->synchronous[RX] = false;
873 		sai->synchronous[TX] = false;
874 		fsl_sai_dai.symmetric_rates = 0;
875 		fsl_sai_dai.symmetric_channels = 0;
876 		fsl_sai_dai.symmetric_samplebits = 0;
877 	}
878 
879 	if (of_find_property(np, "fsl,sai-mclk-direction-output", NULL) &&
880 	    of_device_is_compatible(np, "fsl,imx6ul-sai")) {
881 		gpr = syscon_regmap_lookup_by_compatible("fsl,imx6ul-iomuxc-gpr");
882 		if (IS_ERR(gpr)) {
883 			dev_err(&pdev->dev, "cannot find iomuxc registers\n");
884 			return PTR_ERR(gpr);
885 		}
886 
887 		index = of_alias_get_id(np, "sai");
888 		if (index < 0)
889 			return index;
890 
891 		regmap_update_bits(gpr, IOMUXC_GPR1, MCLK_DIR(index),
892 				   MCLK_DIR(index));
893 	}
894 
895 	sai->dma_params_rx.addr = res->start + FSL_SAI_RDR;
896 	sai->dma_params_tx.addr = res->start + FSL_SAI_TDR;
897 	sai->dma_params_rx.maxburst = FSL_SAI_MAXBURST_RX;
898 	sai->dma_params_tx.maxburst = FSL_SAI_MAXBURST_TX;
899 
900 	platform_set_drvdata(pdev, sai);
901 
902 	ret = devm_snd_soc_register_component(&pdev->dev, &fsl_component,
903 			&fsl_sai_dai, 1);
904 	if (ret)
905 		return ret;
906 
907 	if (sai->sai_on_imx)
908 		return imx_pcm_dma_init(pdev, IMX_SAI_DMABUF_SIZE);
909 	else
910 		return devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
911 }
912 
913 static const struct of_device_id fsl_sai_ids[] = {
914 	{ .compatible = "fsl,vf610-sai", },
915 	{ .compatible = "fsl,imx6sx-sai", },
916 	{ .compatible = "fsl,imx6ul-sai", },
917 	{ /* sentinel */ }
918 };
919 MODULE_DEVICE_TABLE(of, fsl_sai_ids);
920 
921 #ifdef CONFIG_PM_SLEEP
922 static int fsl_sai_suspend(struct device *dev)
923 {
924 	struct fsl_sai *sai = dev_get_drvdata(dev);
925 
926 	regcache_cache_only(sai->regmap, true);
927 	regcache_mark_dirty(sai->regmap);
928 
929 	return 0;
930 }
931 
932 static int fsl_sai_resume(struct device *dev)
933 {
934 	struct fsl_sai *sai = dev_get_drvdata(dev);
935 
936 	regcache_cache_only(sai->regmap, false);
937 	regmap_write(sai->regmap, FSL_SAI_TCSR, FSL_SAI_CSR_SR);
938 	regmap_write(sai->regmap, FSL_SAI_RCSR, FSL_SAI_CSR_SR);
939 	usleep_range(1000, 2000);
940 	regmap_write(sai->regmap, FSL_SAI_TCSR, 0);
941 	regmap_write(sai->regmap, FSL_SAI_RCSR, 0);
942 	return regcache_sync(sai->regmap);
943 }
944 #endif /* CONFIG_PM_SLEEP */
945 
946 static const struct dev_pm_ops fsl_sai_pm_ops = {
947 	SET_SYSTEM_SLEEP_PM_OPS(fsl_sai_suspend, fsl_sai_resume)
948 };
949 
950 static struct platform_driver fsl_sai_driver = {
951 	.probe = fsl_sai_probe,
952 	.driver = {
953 		.name = "fsl-sai",
954 		.pm = &fsl_sai_pm_ops,
955 		.of_match_table = fsl_sai_ids,
956 	},
957 };
958 module_platform_driver(fsl_sai_driver);
959 
960 MODULE_DESCRIPTION("Freescale Soc SAI Interface");
961 MODULE_AUTHOR("Xiubo Li, <Li.Xiubo@freescale.com>");
962 MODULE_ALIAS("platform:fsl-sai");
963 MODULE_LICENSE("GPL");
964