xref: /openbmc/linux/sound/soc/atmel/atmel_ssc_dai.c (revision 22d55f02)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * atmel_ssc_dai.c  --  ALSA SoC ATMEL SSC Audio Layer Platform driver
4  *
5  * Copyright (C) 2005 SAN People
6  * Copyright (C) 2008 Atmel
7  *
8  * Author: Sedji Gaouaou <sedji.gaouaou@atmel.com>
9  *         ATMEL CORP.
10  *
11  * Based on at91-ssc.c by
12  * Frank Mandarino <fmandarino@endrelia.com>
13  * Based on pxa2xx Platform drivers by
14  * Liam Girdwood <lrg@slimlogic.co.uk>
15  */
16 
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/interrupt.h>
20 #include <linux/device.h>
21 #include <linux/delay.h>
22 #include <linux/clk.h>
23 #include <linux/atmel_pdc.h>
24 
25 #include <linux/atmel-ssc.h>
26 #include <sound/core.h>
27 #include <sound/pcm.h>
28 #include <sound/pcm_params.h>
29 #include <sound/initval.h>
30 #include <sound/soc.h>
31 
32 #include "atmel-pcm.h"
33 #include "atmel_ssc_dai.h"
34 
35 
36 #define NUM_SSC_DEVICES		3
37 
38 /*
39  * SSC PDC registers required by the PCM DMA engine.
40  */
41 static struct atmel_pdc_regs pdc_tx_reg = {
42 	.xpr		= ATMEL_PDC_TPR,
43 	.xcr		= ATMEL_PDC_TCR,
44 	.xnpr		= ATMEL_PDC_TNPR,
45 	.xncr		= ATMEL_PDC_TNCR,
46 };
47 
48 static struct atmel_pdc_regs pdc_rx_reg = {
49 	.xpr		= ATMEL_PDC_RPR,
50 	.xcr		= ATMEL_PDC_RCR,
51 	.xnpr		= ATMEL_PDC_RNPR,
52 	.xncr		= ATMEL_PDC_RNCR,
53 };
54 
55 /*
56  * SSC & PDC status bits for transmit and receive.
57  */
58 static struct atmel_ssc_mask ssc_tx_mask = {
59 	.ssc_enable	= SSC_BIT(CR_TXEN),
60 	.ssc_disable	= SSC_BIT(CR_TXDIS),
61 	.ssc_endx	= SSC_BIT(SR_ENDTX),
62 	.ssc_endbuf	= SSC_BIT(SR_TXBUFE),
63 	.ssc_error	= SSC_BIT(SR_OVRUN),
64 	.pdc_enable	= ATMEL_PDC_TXTEN,
65 	.pdc_disable	= ATMEL_PDC_TXTDIS,
66 };
67 
68 static struct atmel_ssc_mask ssc_rx_mask = {
69 	.ssc_enable	= SSC_BIT(CR_RXEN),
70 	.ssc_disable	= SSC_BIT(CR_RXDIS),
71 	.ssc_endx	= SSC_BIT(SR_ENDRX),
72 	.ssc_endbuf	= SSC_BIT(SR_RXBUFF),
73 	.ssc_error	= SSC_BIT(SR_OVRUN),
74 	.pdc_enable	= ATMEL_PDC_RXTEN,
75 	.pdc_disable	= ATMEL_PDC_RXTDIS,
76 };
77 
78 
79 /*
80  * DMA parameters.
81  */
82 static struct atmel_pcm_dma_params ssc_dma_params[NUM_SSC_DEVICES][2] = {
83 	{{
84 	.name		= "SSC0 PCM out",
85 	.pdc		= &pdc_tx_reg,
86 	.mask		= &ssc_tx_mask,
87 	},
88 	{
89 	.name		= "SSC0 PCM in",
90 	.pdc		= &pdc_rx_reg,
91 	.mask		= &ssc_rx_mask,
92 	} },
93 	{{
94 	.name		= "SSC1 PCM out",
95 	.pdc		= &pdc_tx_reg,
96 	.mask		= &ssc_tx_mask,
97 	},
98 	{
99 	.name		= "SSC1 PCM in",
100 	.pdc		= &pdc_rx_reg,
101 	.mask		= &ssc_rx_mask,
102 	} },
103 	{{
104 	.name		= "SSC2 PCM out",
105 	.pdc		= &pdc_tx_reg,
106 	.mask		= &ssc_tx_mask,
107 	},
108 	{
109 	.name		= "SSC2 PCM in",
110 	.pdc		= &pdc_rx_reg,
111 	.mask		= &ssc_rx_mask,
112 	} },
113 };
114 
115 
116 static struct atmel_ssc_info ssc_info[NUM_SSC_DEVICES] = {
117 	{
118 	.name		= "ssc0",
119 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[0].lock),
120 	.dir_mask	= SSC_DIR_MASK_UNUSED,
121 	.initialized	= 0,
122 	},
123 	{
124 	.name		= "ssc1",
125 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[1].lock),
126 	.dir_mask	= SSC_DIR_MASK_UNUSED,
127 	.initialized	= 0,
128 	},
129 	{
130 	.name		= "ssc2",
131 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[2].lock),
132 	.dir_mask	= SSC_DIR_MASK_UNUSED,
133 	.initialized	= 0,
134 	},
135 };
136 
137 
138 /*
139  * SSC interrupt handler.  Passes PDC interrupts to the DMA
140  * interrupt handler in the PCM driver.
141  */
142 static irqreturn_t atmel_ssc_interrupt(int irq, void *dev_id)
143 {
144 	struct atmel_ssc_info *ssc_p = dev_id;
145 	struct atmel_pcm_dma_params *dma_params;
146 	u32 ssc_sr;
147 	u32 ssc_substream_mask;
148 	int i;
149 
150 	ssc_sr = (unsigned long)ssc_readl(ssc_p->ssc->regs, SR)
151 			& (unsigned long)ssc_readl(ssc_p->ssc->regs, IMR);
152 
153 	/*
154 	 * Loop through the substreams attached to this SSC.  If
155 	 * a DMA-related interrupt occurred on that substream, call
156 	 * the DMA interrupt handler function, if one has been
157 	 * registered in the dma_params structure by the PCM driver.
158 	 */
159 	for (i = 0; i < ARRAY_SIZE(ssc_p->dma_params); i++) {
160 		dma_params = ssc_p->dma_params[i];
161 
162 		if ((dma_params != NULL) &&
163 			(dma_params->dma_intr_handler != NULL)) {
164 			ssc_substream_mask = (dma_params->mask->ssc_endx |
165 					dma_params->mask->ssc_endbuf);
166 			if (ssc_sr & ssc_substream_mask) {
167 				dma_params->dma_intr_handler(ssc_sr,
168 						dma_params->
169 						substream);
170 			}
171 		}
172 	}
173 
174 	return IRQ_HANDLED;
175 }
176 
177 /*
178  * When the bit clock is input, limit the maximum rate according to the
179  * Serial Clock Ratio Considerations section from the SSC documentation:
180  *
181  *   The Transmitter and the Receiver can be programmed to operate
182  *   with the clock signals provided on either the TK or RK pins.
183  *   This allows the SSC to support many slave-mode data transfers.
184  *   In this case, the maximum clock speed allowed on the RK pin is:
185  *   - Peripheral clock divided by 2 if Receiver Frame Synchro is input
186  *   - Peripheral clock divided by 3 if Receiver Frame Synchro is output
187  *   In addition, the maximum clock speed allowed on the TK pin is:
188  *   - Peripheral clock divided by 6 if Transmit Frame Synchro is input
189  *   - Peripheral clock divided by 2 if Transmit Frame Synchro is output
190  *
191  * When the bit clock is output, limit the rate according to the
192  * SSC divider restrictions.
193  */
194 static int atmel_ssc_hw_rule_rate(struct snd_pcm_hw_params *params,
195 				  struct snd_pcm_hw_rule *rule)
196 {
197 	struct atmel_ssc_info *ssc_p = rule->private;
198 	struct ssc_device *ssc = ssc_p->ssc;
199 	struct snd_interval *i = hw_param_interval(params, rule->var);
200 	struct snd_interval t;
201 	struct snd_ratnum r = {
202 		.den_min = 1,
203 		.den_max = 4095,
204 		.den_step = 1,
205 	};
206 	unsigned int num = 0, den = 0;
207 	int frame_size;
208 	int mck_div = 2;
209 	int ret;
210 
211 	frame_size = snd_soc_params_to_frame_size(params);
212 	if (frame_size < 0)
213 		return frame_size;
214 
215 	switch (ssc_p->daifmt & SND_SOC_DAIFMT_MASTER_MASK) {
216 	case SND_SOC_DAIFMT_CBM_CFS:
217 		if ((ssc_p->dir_mask & SSC_DIR_MASK_CAPTURE)
218 		    && ssc->clk_from_rk_pin)
219 			/* Receiver Frame Synchro (i.e. capture)
220 			 * is output (format is _CFS) and the RK pin
221 			 * is used for input (format is _CBM_).
222 			 */
223 			mck_div = 3;
224 		break;
225 
226 	case SND_SOC_DAIFMT_CBM_CFM:
227 		if ((ssc_p->dir_mask & SSC_DIR_MASK_PLAYBACK)
228 		    && !ssc->clk_from_rk_pin)
229 			/* Transmit Frame Synchro (i.e. playback)
230 			 * is input (format is _CFM) and the TK pin
231 			 * is used for input (format _CBM_ but not
232 			 * using the RK pin).
233 			 */
234 			mck_div = 6;
235 		break;
236 	}
237 
238 	switch (ssc_p->daifmt & SND_SOC_DAIFMT_MASTER_MASK) {
239 	case SND_SOC_DAIFMT_CBS_CFS:
240 		r.num = ssc_p->mck_rate / mck_div / frame_size;
241 
242 		ret = snd_interval_ratnum(i, 1, &r, &num, &den);
243 		if (ret >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
244 			params->rate_num = num;
245 			params->rate_den = den;
246 		}
247 		break;
248 
249 	case SND_SOC_DAIFMT_CBM_CFS:
250 	case SND_SOC_DAIFMT_CBM_CFM:
251 		t.min = 8000;
252 		t.max = ssc_p->mck_rate / mck_div / frame_size;
253 		t.openmin = t.openmax = 0;
254 		t.integer = 0;
255 		ret = snd_interval_refine(i, &t);
256 		break;
257 
258 	default:
259 		ret = -EINVAL;
260 		break;
261 	}
262 
263 	return ret;
264 }
265 
266 /*-------------------------------------------------------------------------*\
267  * DAI functions
268 \*-------------------------------------------------------------------------*/
269 /*
270  * Startup.  Only that one substream allowed in each direction.
271  */
272 static int atmel_ssc_startup(struct snd_pcm_substream *substream,
273 			     struct snd_soc_dai *dai)
274 {
275 	struct platform_device *pdev = to_platform_device(dai->dev);
276 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
277 	struct atmel_pcm_dma_params *dma_params;
278 	int dir, dir_mask;
279 	int ret;
280 
281 	pr_debug("atmel_ssc_startup: SSC_SR=0x%x\n",
282 		ssc_readl(ssc_p->ssc->regs, SR));
283 
284 	/* Enable PMC peripheral clock for this SSC */
285 	pr_debug("atmel_ssc_dai: Starting clock\n");
286 	clk_enable(ssc_p->ssc->clk);
287 	ssc_p->mck_rate = clk_get_rate(ssc_p->ssc->clk);
288 
289 	/* Reset the SSC unless initialized to keep it in a clean state */
290 	if (!ssc_p->initialized)
291 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
292 
293 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
294 		dir = 0;
295 		dir_mask = SSC_DIR_MASK_PLAYBACK;
296 	} else {
297 		dir = 1;
298 		dir_mask = SSC_DIR_MASK_CAPTURE;
299 	}
300 
301 	ret = snd_pcm_hw_rule_add(substream->runtime, 0,
302 				  SNDRV_PCM_HW_PARAM_RATE,
303 				  atmel_ssc_hw_rule_rate,
304 				  ssc_p,
305 				  SNDRV_PCM_HW_PARAM_FRAME_BITS,
306 				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
307 	if (ret < 0) {
308 		dev_err(dai->dev, "Failed to specify rate rule: %d\n", ret);
309 		return ret;
310 	}
311 
312 	dma_params = &ssc_dma_params[pdev->id][dir];
313 	dma_params->ssc = ssc_p->ssc;
314 	dma_params->substream = substream;
315 
316 	ssc_p->dma_params[dir] = dma_params;
317 
318 	snd_soc_dai_set_dma_data(dai, substream, dma_params);
319 
320 	spin_lock_irq(&ssc_p->lock);
321 	if (ssc_p->dir_mask & dir_mask) {
322 		spin_unlock_irq(&ssc_p->lock);
323 		return -EBUSY;
324 	}
325 	ssc_p->dir_mask |= dir_mask;
326 	spin_unlock_irq(&ssc_p->lock);
327 
328 	return 0;
329 }
330 
331 /*
332  * Shutdown.  Clear DMA parameters and shutdown the SSC if there
333  * are no other substreams open.
334  */
335 static void atmel_ssc_shutdown(struct snd_pcm_substream *substream,
336 			       struct snd_soc_dai *dai)
337 {
338 	struct platform_device *pdev = to_platform_device(dai->dev);
339 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
340 	struct atmel_pcm_dma_params *dma_params;
341 	int dir, dir_mask;
342 
343 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
344 		dir = 0;
345 	else
346 		dir = 1;
347 
348 	dma_params = ssc_p->dma_params[dir];
349 
350 	if (dma_params != NULL) {
351 		dma_params->ssc = NULL;
352 		dma_params->substream = NULL;
353 		ssc_p->dma_params[dir] = NULL;
354 	}
355 
356 	dir_mask = 1 << dir;
357 
358 	spin_lock_irq(&ssc_p->lock);
359 	ssc_p->dir_mask &= ~dir_mask;
360 	if (!ssc_p->dir_mask) {
361 		if (ssc_p->initialized) {
362 			free_irq(ssc_p->ssc->irq, ssc_p);
363 			ssc_p->initialized = 0;
364 		}
365 
366 		/* Reset the SSC */
367 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
368 		/* Clear the SSC dividers */
369 		ssc_p->cmr_div = ssc_p->tcmr_period = ssc_p->rcmr_period = 0;
370 		ssc_p->forced_divider = 0;
371 	}
372 	spin_unlock_irq(&ssc_p->lock);
373 
374 	/* Shutdown the SSC clock. */
375 	pr_debug("atmel_ssc_dai: Stopping clock\n");
376 	clk_disable(ssc_p->ssc->clk);
377 }
378 
379 
380 /*
381  * Record the DAI format for use in hw_params().
382  */
383 static int atmel_ssc_set_dai_fmt(struct snd_soc_dai *cpu_dai,
384 		unsigned int fmt)
385 {
386 	struct platform_device *pdev = to_platform_device(cpu_dai->dev);
387 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
388 
389 	ssc_p->daifmt = fmt;
390 	return 0;
391 }
392 
393 /*
394  * Record SSC clock dividers for use in hw_params().
395  */
396 static int atmel_ssc_set_dai_clkdiv(struct snd_soc_dai *cpu_dai,
397 	int div_id, int div)
398 {
399 	struct platform_device *pdev = to_platform_device(cpu_dai->dev);
400 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
401 
402 	switch (div_id) {
403 	case ATMEL_SSC_CMR_DIV:
404 		/*
405 		 * The same master clock divider is used for both
406 		 * transmit and receive, so if a value has already
407 		 * been set, it must match this value.
408 		 */
409 		if (ssc_p->dir_mask !=
410 			(SSC_DIR_MASK_PLAYBACK | SSC_DIR_MASK_CAPTURE))
411 			ssc_p->cmr_div = div;
412 		else if (ssc_p->cmr_div == 0)
413 			ssc_p->cmr_div = div;
414 		else
415 			if (div != ssc_p->cmr_div)
416 				return -EBUSY;
417 		ssc_p->forced_divider |= BIT(ATMEL_SSC_CMR_DIV);
418 		break;
419 
420 	case ATMEL_SSC_TCMR_PERIOD:
421 		ssc_p->tcmr_period = div;
422 		ssc_p->forced_divider |= BIT(ATMEL_SSC_TCMR_PERIOD);
423 		break;
424 
425 	case ATMEL_SSC_RCMR_PERIOD:
426 		ssc_p->rcmr_period = div;
427 		ssc_p->forced_divider |= BIT(ATMEL_SSC_RCMR_PERIOD);
428 		break;
429 
430 	default:
431 		return -EINVAL;
432 	}
433 
434 	return 0;
435 }
436 
437 /* Is the cpu-dai master of the frame clock? */
438 static int atmel_ssc_cfs(struct atmel_ssc_info *ssc_p)
439 {
440 	switch (ssc_p->daifmt & SND_SOC_DAIFMT_MASTER_MASK) {
441 	case SND_SOC_DAIFMT_CBM_CFS:
442 	case SND_SOC_DAIFMT_CBS_CFS:
443 		return 1;
444 	}
445 	return 0;
446 }
447 
448 /* Is the cpu-dai master of the bit clock? */
449 static int atmel_ssc_cbs(struct atmel_ssc_info *ssc_p)
450 {
451 	switch (ssc_p->daifmt & SND_SOC_DAIFMT_MASTER_MASK) {
452 	case SND_SOC_DAIFMT_CBS_CFM:
453 	case SND_SOC_DAIFMT_CBS_CFS:
454 		return 1;
455 	}
456 	return 0;
457 }
458 
459 /*
460  * Configure the SSC.
461  */
462 static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
463 	struct snd_pcm_hw_params *params,
464 	struct snd_soc_dai *dai)
465 {
466 	struct platform_device *pdev = to_platform_device(dai->dev);
467 	int id = pdev->id;
468 	struct atmel_ssc_info *ssc_p = &ssc_info[id];
469 	struct ssc_device *ssc = ssc_p->ssc;
470 	struct atmel_pcm_dma_params *dma_params;
471 	int dir, channels, bits;
472 	u32 tfmr, rfmr, tcmr, rcmr;
473 	int ret;
474 	int fslen, fslen_ext;
475 	u32 cmr_div;
476 	u32 tcmr_period;
477 	u32 rcmr_period;
478 
479 	/*
480 	 * Currently, there is only one set of dma params for
481 	 * each direction.  If more are added, this code will
482 	 * have to be changed to select the proper set.
483 	 */
484 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
485 		dir = 0;
486 	else
487 		dir = 1;
488 
489 	/*
490 	 * If the cpu dai should provide BCLK, but noone has provided the
491 	 * divider needed for that to work, fall back to something sensible.
492 	 */
493 	cmr_div = ssc_p->cmr_div;
494 	if (!(ssc_p->forced_divider & BIT(ATMEL_SSC_CMR_DIV)) &&
495 	    atmel_ssc_cbs(ssc_p)) {
496 		int bclk_rate = snd_soc_params_to_bclk(params);
497 
498 		if (bclk_rate < 0) {
499 			dev_err(dai->dev, "unable to calculate cmr_div: %d\n",
500 				bclk_rate);
501 			return bclk_rate;
502 		}
503 
504 		cmr_div = DIV_ROUND_CLOSEST(ssc_p->mck_rate, 2 * bclk_rate);
505 	}
506 
507 	/*
508 	 * If the cpu dai should provide LRCLK, but noone has provided the
509 	 * dividers needed for that to work, fall back to something sensible.
510 	 */
511 	tcmr_period = ssc_p->tcmr_period;
512 	rcmr_period = ssc_p->rcmr_period;
513 	if (atmel_ssc_cfs(ssc_p)) {
514 		int frame_size = snd_soc_params_to_frame_size(params);
515 
516 		if (frame_size < 0) {
517 			dev_err(dai->dev,
518 				"unable to calculate tx/rx cmr_period: %d\n",
519 				frame_size);
520 			return frame_size;
521 		}
522 
523 		if (!(ssc_p->forced_divider & BIT(ATMEL_SSC_TCMR_PERIOD)))
524 			tcmr_period = frame_size / 2 - 1;
525 		if (!(ssc_p->forced_divider & BIT(ATMEL_SSC_RCMR_PERIOD)))
526 			rcmr_period = frame_size / 2 - 1;
527 	}
528 
529 	dma_params = ssc_p->dma_params[dir];
530 
531 	channels = params_channels(params);
532 
533 	/*
534 	 * Determine sample size in bits and the PDC increment.
535 	 */
536 	switch (params_format(params)) {
537 	case SNDRV_PCM_FORMAT_S8:
538 		bits = 8;
539 		dma_params->pdc_xfer_size = 1;
540 		break;
541 	case SNDRV_PCM_FORMAT_S16_LE:
542 		bits = 16;
543 		dma_params->pdc_xfer_size = 2;
544 		break;
545 	case SNDRV_PCM_FORMAT_S24_LE:
546 		bits = 24;
547 		dma_params->pdc_xfer_size = 4;
548 		break;
549 	case SNDRV_PCM_FORMAT_S32_LE:
550 		bits = 32;
551 		dma_params->pdc_xfer_size = 4;
552 		break;
553 	default:
554 		printk(KERN_WARNING "atmel_ssc_dai: unsupported PCM format");
555 		return -EINVAL;
556 	}
557 
558 	/*
559 	 * Compute SSC register settings.
560 	 */
561 	switch (ssc_p->daifmt
562 		& (SND_SOC_DAIFMT_FORMAT_MASK | SND_SOC_DAIFMT_MASTER_MASK)) {
563 
564 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBS_CFS:
565 		/*
566 		 * I2S format, SSC provides BCLK and LRC clocks.
567 		 *
568 		 * The SSC transmit and receive clocks are generated
569 		 * from the MCK divider, and the BCLK signal
570 		 * is output on the SSC TK line.
571 		 */
572 
573 		if (bits > 16 && !ssc->pdata->has_fslen_ext) {
574 			dev_err(dai->dev,
575 				"sample size %d is too large for SSC device\n",
576 				bits);
577 			return -EINVAL;
578 		}
579 
580 		fslen_ext = (bits - 1) / 16;
581 		fslen = (bits - 1) % 16;
582 
583 		rcmr =	  SSC_BF(RCMR_PERIOD, rcmr_period)
584 			| SSC_BF(RCMR_STTDLY, START_DELAY)
585 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
586 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
587 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
588 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
589 
590 		rfmr =    SSC_BF(RFMR_FSLEN_EXT, fslen_ext)
591 			| SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
592 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NEGATIVE)
593 			| SSC_BF(RFMR_FSLEN, fslen)
594 			| SSC_BF(RFMR_DATNB, (channels - 1))
595 			| SSC_BIT(RFMR_MSBF)
596 			| SSC_BF(RFMR_LOOP, 0)
597 			| SSC_BF(RFMR_DATLEN, (bits - 1));
598 
599 		tcmr =	  SSC_BF(TCMR_PERIOD, tcmr_period)
600 			| SSC_BF(TCMR_STTDLY, START_DELAY)
601 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
602 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
603 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
604 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
605 
606 		tfmr =    SSC_BF(TFMR_FSLEN_EXT, fslen_ext)
607 			| SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
608 			| SSC_BF(TFMR_FSDEN, 0)
609 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NEGATIVE)
610 			| SSC_BF(TFMR_FSLEN, fslen)
611 			| SSC_BF(TFMR_DATNB, (channels - 1))
612 			| SSC_BIT(TFMR_MSBF)
613 			| SSC_BF(TFMR_DATDEF, 0)
614 			| SSC_BF(TFMR_DATLEN, (bits - 1));
615 		break;
616 
617 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBM_CFM:
618 		/* I2S format, CODEC supplies BCLK and LRC clocks. */
619 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
620 			| SSC_BF(RCMR_STTDLY, START_DELAY)
621 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
622 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
623 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
624 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
625 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
626 
627 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
628 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
629 			| SSC_BF(RFMR_FSLEN, 0)
630 			| SSC_BF(RFMR_DATNB, (channels - 1))
631 			| SSC_BIT(RFMR_MSBF)
632 			| SSC_BF(RFMR_LOOP, 0)
633 			| SSC_BF(RFMR_DATLEN, (bits - 1));
634 
635 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
636 			| SSC_BF(TCMR_STTDLY, START_DELAY)
637 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
638 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
639 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
640 			| SSC_BF(TCMR_CKS, ssc->clk_from_rk_pin ?
641 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
642 
643 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
644 			| SSC_BF(TFMR_FSDEN, 0)
645 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
646 			| SSC_BF(TFMR_FSLEN, 0)
647 			| SSC_BF(TFMR_DATNB, (channels - 1))
648 			| SSC_BIT(TFMR_MSBF)
649 			| SSC_BF(TFMR_DATDEF, 0)
650 			| SSC_BF(TFMR_DATLEN, (bits - 1));
651 		break;
652 
653 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBM_CFS:
654 		/* I2S format, CODEC supplies BCLK, SSC supplies LRCLK. */
655 		if (bits > 16 && !ssc->pdata->has_fslen_ext) {
656 			dev_err(dai->dev,
657 				"sample size %d is too large for SSC device\n",
658 				bits);
659 			return -EINVAL;
660 		}
661 
662 		fslen_ext = (bits - 1) / 16;
663 		fslen = (bits - 1) % 16;
664 
665 		rcmr =	  SSC_BF(RCMR_PERIOD, rcmr_period)
666 			| SSC_BF(RCMR_STTDLY, START_DELAY)
667 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
668 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
669 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
670 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
671 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
672 
673 		rfmr =    SSC_BF(RFMR_FSLEN_EXT, fslen_ext)
674 			| SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
675 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NEGATIVE)
676 			| SSC_BF(RFMR_FSLEN, fslen)
677 			| SSC_BF(RFMR_DATNB, (channels - 1))
678 			| SSC_BIT(RFMR_MSBF)
679 			| SSC_BF(RFMR_LOOP, 0)
680 			| SSC_BF(RFMR_DATLEN, (bits - 1));
681 
682 		tcmr =	  SSC_BF(TCMR_PERIOD, tcmr_period)
683 			| SSC_BF(TCMR_STTDLY, START_DELAY)
684 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
685 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
686 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
687 			| SSC_BF(TCMR_CKS, ssc->clk_from_rk_pin ?
688 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
689 
690 		tfmr =    SSC_BF(TFMR_FSLEN_EXT, fslen_ext)
691 			| SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_NEGATIVE)
692 			| SSC_BF(TFMR_FSDEN, 0)
693 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NEGATIVE)
694 			| SSC_BF(TFMR_FSLEN, fslen)
695 			| SSC_BF(TFMR_DATNB, (channels - 1))
696 			| SSC_BIT(TFMR_MSBF)
697 			| SSC_BF(TFMR_DATDEF, 0)
698 			| SSC_BF(TFMR_DATLEN, (bits - 1));
699 		break;
700 
701 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBS_CFS:
702 		/*
703 		 * DSP/PCM Mode A format, SSC provides BCLK and LRC clocks.
704 		 *
705 		 * The SSC transmit and receive clocks are generated from the
706 		 * MCK divider, and the BCLK signal is output
707 		 * on the SSC TK line.
708 		 */
709 		rcmr =	  SSC_BF(RCMR_PERIOD, rcmr_period)
710 			| SSC_BF(RCMR_STTDLY, 1)
711 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
712 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
713 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
714 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
715 
716 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
717 			| SSC_BF(RFMR_FSOS, SSC_FSOS_POSITIVE)
718 			| SSC_BF(RFMR_FSLEN, 0)
719 			| SSC_BF(RFMR_DATNB, (channels - 1))
720 			| SSC_BIT(RFMR_MSBF)
721 			| SSC_BF(RFMR_LOOP, 0)
722 			| SSC_BF(RFMR_DATLEN, (bits - 1));
723 
724 		tcmr =	  SSC_BF(TCMR_PERIOD, tcmr_period)
725 			| SSC_BF(TCMR_STTDLY, 1)
726 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
727 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
728 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
729 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
730 
731 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
732 			| SSC_BF(TFMR_FSDEN, 0)
733 			| SSC_BF(TFMR_FSOS, SSC_FSOS_POSITIVE)
734 			| SSC_BF(TFMR_FSLEN, 0)
735 			| SSC_BF(TFMR_DATNB, (channels - 1))
736 			| SSC_BIT(TFMR_MSBF)
737 			| SSC_BF(TFMR_DATDEF, 0)
738 			| SSC_BF(TFMR_DATLEN, (bits - 1));
739 		break;
740 
741 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBM_CFM:
742 		/*
743 		 * DSP/PCM Mode A format, CODEC supplies BCLK and LRC clocks.
744 		 *
745 		 * Data is transferred on first BCLK after LRC pulse rising
746 		 * edge.If stereo, the right channel data is contiguous with
747 		 * the left channel data.
748 		 */
749 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
750 			| SSC_BF(RCMR_STTDLY, START_DELAY)
751 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
752 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
753 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
754 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
755 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
756 
757 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
758 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
759 			| SSC_BF(RFMR_FSLEN, 0)
760 			| SSC_BF(RFMR_DATNB, (channels - 1))
761 			| SSC_BIT(RFMR_MSBF)
762 			| SSC_BF(RFMR_LOOP, 0)
763 			| SSC_BF(RFMR_DATLEN, (bits - 1));
764 
765 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
766 			| SSC_BF(TCMR_STTDLY, START_DELAY)
767 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
768 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
769 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
770 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
771 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
772 
773 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
774 			| SSC_BF(TFMR_FSDEN, 0)
775 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
776 			| SSC_BF(TFMR_FSLEN, 0)
777 			| SSC_BF(TFMR_DATNB, (channels - 1))
778 			| SSC_BIT(TFMR_MSBF)
779 			| SSC_BF(TFMR_DATDEF, 0)
780 			| SSC_BF(TFMR_DATLEN, (bits - 1));
781 		break;
782 
783 	default:
784 		printk(KERN_WARNING "atmel_ssc_dai: unsupported DAI format 0x%x\n",
785 			ssc_p->daifmt);
786 		return -EINVAL;
787 	}
788 	pr_debug("atmel_ssc_hw_params: "
789 			"RCMR=%08x RFMR=%08x TCMR=%08x TFMR=%08x\n",
790 			rcmr, rfmr, tcmr, tfmr);
791 
792 	if (!ssc_p->initialized) {
793 		if (!ssc_p->ssc->pdata->use_dma) {
794 			ssc_writel(ssc_p->ssc->regs, PDC_RPR, 0);
795 			ssc_writel(ssc_p->ssc->regs, PDC_RCR, 0);
796 			ssc_writel(ssc_p->ssc->regs, PDC_RNPR, 0);
797 			ssc_writel(ssc_p->ssc->regs, PDC_RNCR, 0);
798 
799 			ssc_writel(ssc_p->ssc->regs, PDC_TPR, 0);
800 			ssc_writel(ssc_p->ssc->regs, PDC_TCR, 0);
801 			ssc_writel(ssc_p->ssc->regs, PDC_TNPR, 0);
802 			ssc_writel(ssc_p->ssc->regs, PDC_TNCR, 0);
803 		}
804 
805 		ret = request_irq(ssc_p->ssc->irq, atmel_ssc_interrupt, 0,
806 				ssc_p->name, ssc_p);
807 		if (ret < 0) {
808 			printk(KERN_WARNING
809 					"atmel_ssc_dai: request_irq failure\n");
810 			pr_debug("Atmel_ssc_dai: Stopping clock\n");
811 			clk_disable(ssc_p->ssc->clk);
812 			return ret;
813 		}
814 
815 		ssc_p->initialized = 1;
816 	}
817 
818 	/* set SSC clock mode register */
819 	ssc_writel(ssc_p->ssc->regs, CMR, cmr_div);
820 
821 	/* set receive clock mode and format */
822 	ssc_writel(ssc_p->ssc->regs, RCMR, rcmr);
823 	ssc_writel(ssc_p->ssc->regs, RFMR, rfmr);
824 
825 	/* set transmit clock mode and format */
826 	ssc_writel(ssc_p->ssc->regs, TCMR, tcmr);
827 	ssc_writel(ssc_p->ssc->regs, TFMR, tfmr);
828 
829 	pr_debug("atmel_ssc_dai,hw_params: SSC initialized\n");
830 	return 0;
831 }
832 
833 
834 static int atmel_ssc_prepare(struct snd_pcm_substream *substream,
835 			     struct snd_soc_dai *dai)
836 {
837 	struct platform_device *pdev = to_platform_device(dai->dev);
838 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
839 	struct atmel_pcm_dma_params *dma_params;
840 	int dir;
841 
842 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
843 		dir = 0;
844 	else
845 		dir = 1;
846 
847 	dma_params = ssc_p->dma_params[dir];
848 
849 	ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
850 	ssc_writel(ssc_p->ssc->regs, IDR, dma_params->mask->ssc_error);
851 
852 	pr_debug("%s enabled SSC_SR=0x%08x\n",
853 			dir ? "receive" : "transmit",
854 			ssc_readl(ssc_p->ssc->regs, SR));
855 	return 0;
856 }
857 
858 static int atmel_ssc_trigger(struct snd_pcm_substream *substream,
859 			     int cmd, struct snd_soc_dai *dai)
860 {
861 	struct platform_device *pdev = to_platform_device(dai->dev);
862 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
863 	struct atmel_pcm_dma_params *dma_params;
864 	int dir;
865 
866 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
867 		dir = 0;
868 	else
869 		dir = 1;
870 
871 	dma_params = ssc_p->dma_params[dir];
872 
873 	switch (cmd) {
874 	case SNDRV_PCM_TRIGGER_START:
875 	case SNDRV_PCM_TRIGGER_RESUME:
876 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
877 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_enable);
878 		break;
879 	default:
880 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
881 		break;
882 	}
883 
884 	return 0;
885 }
886 
887 #ifdef CONFIG_PM
888 static int atmel_ssc_suspend(struct snd_soc_dai *cpu_dai)
889 {
890 	struct atmel_ssc_info *ssc_p;
891 	struct platform_device *pdev = to_platform_device(cpu_dai->dev);
892 
893 	if (!cpu_dai->active)
894 		return 0;
895 
896 	ssc_p = &ssc_info[pdev->id];
897 
898 	/* Save the status register before disabling transmit and receive */
899 	ssc_p->ssc_state.ssc_sr = ssc_readl(ssc_p->ssc->regs, SR);
900 	ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_TXDIS) | SSC_BIT(CR_RXDIS));
901 
902 	/* Save the current interrupt mask, then disable unmasked interrupts */
903 	ssc_p->ssc_state.ssc_imr = ssc_readl(ssc_p->ssc->regs, IMR);
904 	ssc_writel(ssc_p->ssc->regs, IDR, ssc_p->ssc_state.ssc_imr);
905 
906 	ssc_p->ssc_state.ssc_cmr = ssc_readl(ssc_p->ssc->regs, CMR);
907 	ssc_p->ssc_state.ssc_rcmr = ssc_readl(ssc_p->ssc->regs, RCMR);
908 	ssc_p->ssc_state.ssc_rfmr = ssc_readl(ssc_p->ssc->regs, RFMR);
909 	ssc_p->ssc_state.ssc_tcmr = ssc_readl(ssc_p->ssc->regs, TCMR);
910 	ssc_p->ssc_state.ssc_tfmr = ssc_readl(ssc_p->ssc->regs, TFMR);
911 
912 	return 0;
913 }
914 
915 
916 
917 static int atmel_ssc_resume(struct snd_soc_dai *cpu_dai)
918 {
919 	struct atmel_ssc_info *ssc_p;
920 	struct platform_device *pdev = to_platform_device(cpu_dai->dev);
921 	u32 cr;
922 
923 	if (!cpu_dai->active)
924 		return 0;
925 
926 	ssc_p = &ssc_info[pdev->id];
927 
928 	/* restore SSC register settings */
929 	ssc_writel(ssc_p->ssc->regs, TFMR, ssc_p->ssc_state.ssc_tfmr);
930 	ssc_writel(ssc_p->ssc->regs, TCMR, ssc_p->ssc_state.ssc_tcmr);
931 	ssc_writel(ssc_p->ssc->regs, RFMR, ssc_p->ssc_state.ssc_rfmr);
932 	ssc_writel(ssc_p->ssc->regs, RCMR, ssc_p->ssc_state.ssc_rcmr);
933 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->ssc_state.ssc_cmr);
934 
935 	/* re-enable interrupts */
936 	ssc_writel(ssc_p->ssc->regs, IER, ssc_p->ssc_state.ssc_imr);
937 
938 	/* Re-enable receive and transmit as appropriate */
939 	cr = 0;
940 	cr |=
941 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_RXEN)) ? SSC_BIT(CR_RXEN) : 0;
942 	cr |=
943 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_TXEN)) ? SSC_BIT(CR_TXEN) : 0;
944 	ssc_writel(ssc_p->ssc->regs, CR, cr);
945 
946 	return 0;
947 }
948 #else /* CONFIG_PM */
949 #  define atmel_ssc_suspend	NULL
950 #  define atmel_ssc_resume	NULL
951 #endif /* CONFIG_PM */
952 
953 #define ATMEL_SSC_FORMATS (SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_S16_LE |\
954 			  SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
955 
956 static const struct snd_soc_dai_ops atmel_ssc_dai_ops = {
957 	.startup	= atmel_ssc_startup,
958 	.shutdown	= atmel_ssc_shutdown,
959 	.prepare	= atmel_ssc_prepare,
960 	.trigger	= atmel_ssc_trigger,
961 	.hw_params	= atmel_ssc_hw_params,
962 	.set_fmt	= atmel_ssc_set_dai_fmt,
963 	.set_clkdiv	= atmel_ssc_set_dai_clkdiv,
964 };
965 
966 static struct snd_soc_dai_driver atmel_ssc_dai = {
967 		.suspend = atmel_ssc_suspend,
968 		.resume = atmel_ssc_resume,
969 		.playback = {
970 			.channels_min = 1,
971 			.channels_max = 2,
972 			.rates = SNDRV_PCM_RATE_CONTINUOUS,
973 			.rate_min = 8000,
974 			.rate_max = 384000,
975 			.formats = ATMEL_SSC_FORMATS,},
976 		.capture = {
977 			.channels_min = 1,
978 			.channels_max = 2,
979 			.rates = SNDRV_PCM_RATE_CONTINUOUS,
980 			.rate_min = 8000,
981 			.rate_max = 384000,
982 			.formats = ATMEL_SSC_FORMATS,},
983 		.ops = &atmel_ssc_dai_ops,
984 };
985 
986 static const struct snd_soc_component_driver atmel_ssc_component = {
987 	.name		= "atmel-ssc",
988 };
989 
990 static int asoc_ssc_init(struct device *dev)
991 {
992 	struct ssc_device *ssc = dev_get_drvdata(dev);
993 	int ret;
994 
995 	ret = devm_snd_soc_register_component(dev, &atmel_ssc_component,
996 					 &atmel_ssc_dai, 1);
997 	if (ret) {
998 		dev_err(dev, "Could not register DAI: %d\n", ret);
999 		return ret;
1000 	}
1001 
1002 	if (ssc->pdata->use_dma)
1003 		ret = atmel_pcm_dma_platform_register(dev);
1004 	else
1005 		ret = atmel_pcm_pdc_platform_register(dev);
1006 
1007 	if (ret) {
1008 		dev_err(dev, "Could not register PCM: %d\n", ret);
1009 		return ret;
1010 	}
1011 
1012 	return 0;
1013 }
1014 
1015 static void asoc_ssc_exit(struct device *dev)
1016 {
1017 	struct ssc_device *ssc = dev_get_drvdata(dev);
1018 
1019 	if (ssc->pdata->use_dma)
1020 		atmel_pcm_dma_platform_unregister(dev);
1021 	else
1022 		atmel_pcm_pdc_platform_unregister(dev);
1023 }
1024 
1025 /**
1026  * atmel_ssc_set_audio - Allocate the specified SSC for audio use.
1027  */
1028 int atmel_ssc_set_audio(int ssc_id)
1029 {
1030 	struct ssc_device *ssc;
1031 	int ret;
1032 
1033 	/* If we can grab the SSC briefly to parent the DAI device off it */
1034 	ssc = ssc_request(ssc_id);
1035 	if (IS_ERR(ssc)) {
1036 		pr_err("Unable to parent ASoC SSC DAI on SSC: %ld\n",
1037 			PTR_ERR(ssc));
1038 		return PTR_ERR(ssc);
1039 	} else {
1040 		ssc_info[ssc_id].ssc = ssc;
1041 	}
1042 
1043 	ret = asoc_ssc_init(&ssc->pdev->dev);
1044 
1045 	return ret;
1046 }
1047 EXPORT_SYMBOL_GPL(atmel_ssc_set_audio);
1048 
1049 void atmel_ssc_put_audio(int ssc_id)
1050 {
1051 	struct ssc_device *ssc = ssc_info[ssc_id].ssc;
1052 
1053 	asoc_ssc_exit(&ssc->pdev->dev);
1054 	ssc_free(ssc);
1055 }
1056 EXPORT_SYMBOL_GPL(atmel_ssc_put_audio);
1057 
1058 /* Module information */
1059 MODULE_AUTHOR("Sedji Gaouaou, sedji.gaouaou@atmel.com, www.atmel.com");
1060 MODULE_DESCRIPTION("ATMEL SSC ASoC Interface");
1061 MODULE_LICENSE("GPL");
1062