xref: /openbmc/linux/sound/soc/atmel/atmel_ssc_dai.c (revision 3e103a65)
1 /*
2  * atmel_ssc_dai.c  --  ALSA SoC ATMEL SSC Audio Layer Platform driver
3  *
4  * Copyright (C) 2005 SAN People
5  * Copyright (C) 2008 Atmel
6  *
7  * Author: Sedji Gaouaou <sedji.gaouaou@atmel.com>
8  *         ATMEL CORP.
9  *
10  * Based on at91-ssc.c by
11  * Frank Mandarino <fmandarino@endrelia.com>
12  * Based on pxa2xx Platform drivers by
13  * Liam Girdwood <lrg@slimlogic.co.uk>
14  *
15  * This program is free software; you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License as published by
17  * the Free Software Foundation; either version 2 of the License, or
18  * (at your option) any later version.
19  *
20  * This program is distributed in the hope that it will be useful,
21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
23  * GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program; if not, write to the Free Software
27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
28  */
29 
30 #include <linux/init.h>
31 #include <linux/module.h>
32 #include <linux/interrupt.h>
33 #include <linux/device.h>
34 #include <linux/delay.h>
35 #include <linux/clk.h>
36 #include <linux/atmel_pdc.h>
37 
38 #include <linux/atmel-ssc.h>
39 #include <sound/core.h>
40 #include <sound/pcm.h>
41 #include <sound/pcm_params.h>
42 #include <sound/initval.h>
43 #include <sound/soc.h>
44 
45 #include "atmel-pcm.h"
46 #include "atmel_ssc_dai.h"
47 
48 
49 #define NUM_SSC_DEVICES		3
50 
51 /*
52  * SSC PDC registers required by the PCM DMA engine.
53  */
54 static struct atmel_pdc_regs pdc_tx_reg = {
55 	.xpr		= ATMEL_PDC_TPR,
56 	.xcr		= ATMEL_PDC_TCR,
57 	.xnpr		= ATMEL_PDC_TNPR,
58 	.xncr		= ATMEL_PDC_TNCR,
59 };
60 
61 static struct atmel_pdc_regs pdc_rx_reg = {
62 	.xpr		= ATMEL_PDC_RPR,
63 	.xcr		= ATMEL_PDC_RCR,
64 	.xnpr		= ATMEL_PDC_RNPR,
65 	.xncr		= ATMEL_PDC_RNCR,
66 };
67 
68 /*
69  * SSC & PDC status bits for transmit and receive.
70  */
71 static struct atmel_ssc_mask ssc_tx_mask = {
72 	.ssc_enable	= SSC_BIT(CR_TXEN),
73 	.ssc_disable	= SSC_BIT(CR_TXDIS),
74 	.ssc_endx	= SSC_BIT(SR_ENDTX),
75 	.ssc_endbuf	= SSC_BIT(SR_TXBUFE),
76 	.ssc_error	= SSC_BIT(SR_OVRUN),
77 	.pdc_enable	= ATMEL_PDC_TXTEN,
78 	.pdc_disable	= ATMEL_PDC_TXTDIS,
79 };
80 
81 static struct atmel_ssc_mask ssc_rx_mask = {
82 	.ssc_enable	= SSC_BIT(CR_RXEN),
83 	.ssc_disable	= SSC_BIT(CR_RXDIS),
84 	.ssc_endx	= SSC_BIT(SR_ENDRX),
85 	.ssc_endbuf	= SSC_BIT(SR_RXBUFF),
86 	.ssc_error	= SSC_BIT(SR_OVRUN),
87 	.pdc_enable	= ATMEL_PDC_RXTEN,
88 	.pdc_disable	= ATMEL_PDC_RXTDIS,
89 };
90 
91 
92 /*
93  * DMA parameters.
94  */
95 static struct atmel_pcm_dma_params ssc_dma_params[NUM_SSC_DEVICES][2] = {
96 	{{
97 	.name		= "SSC0 PCM out",
98 	.pdc		= &pdc_tx_reg,
99 	.mask		= &ssc_tx_mask,
100 	},
101 	{
102 	.name		= "SSC0 PCM in",
103 	.pdc		= &pdc_rx_reg,
104 	.mask		= &ssc_rx_mask,
105 	} },
106 	{{
107 	.name		= "SSC1 PCM out",
108 	.pdc		= &pdc_tx_reg,
109 	.mask		= &ssc_tx_mask,
110 	},
111 	{
112 	.name		= "SSC1 PCM in",
113 	.pdc		= &pdc_rx_reg,
114 	.mask		= &ssc_rx_mask,
115 	} },
116 	{{
117 	.name		= "SSC2 PCM out",
118 	.pdc		= &pdc_tx_reg,
119 	.mask		= &ssc_tx_mask,
120 	},
121 	{
122 	.name		= "SSC2 PCM in",
123 	.pdc		= &pdc_rx_reg,
124 	.mask		= &ssc_rx_mask,
125 	} },
126 };
127 
128 
129 static struct atmel_ssc_info ssc_info[NUM_SSC_DEVICES] = {
130 	{
131 	.name		= "ssc0",
132 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[0].lock),
133 	.dir_mask	= SSC_DIR_MASK_UNUSED,
134 	.initialized	= 0,
135 	},
136 	{
137 	.name		= "ssc1",
138 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[1].lock),
139 	.dir_mask	= SSC_DIR_MASK_UNUSED,
140 	.initialized	= 0,
141 	},
142 	{
143 	.name		= "ssc2",
144 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[2].lock),
145 	.dir_mask	= SSC_DIR_MASK_UNUSED,
146 	.initialized	= 0,
147 	},
148 };
149 
150 
151 /*
152  * SSC interrupt handler.  Passes PDC interrupts to the DMA
153  * interrupt handler in the PCM driver.
154  */
155 static irqreturn_t atmel_ssc_interrupt(int irq, void *dev_id)
156 {
157 	struct atmel_ssc_info *ssc_p = dev_id;
158 	struct atmel_pcm_dma_params *dma_params;
159 	u32 ssc_sr;
160 	u32 ssc_substream_mask;
161 	int i;
162 
163 	ssc_sr = (unsigned long)ssc_readl(ssc_p->ssc->regs, SR)
164 			& (unsigned long)ssc_readl(ssc_p->ssc->regs, IMR);
165 
166 	/*
167 	 * Loop through the substreams attached to this SSC.  If
168 	 * a DMA-related interrupt occurred on that substream, call
169 	 * the DMA interrupt handler function, if one has been
170 	 * registered in the dma_params structure by the PCM driver.
171 	 */
172 	for (i = 0; i < ARRAY_SIZE(ssc_p->dma_params); i++) {
173 		dma_params = ssc_p->dma_params[i];
174 
175 		if ((dma_params != NULL) &&
176 			(dma_params->dma_intr_handler != NULL)) {
177 			ssc_substream_mask = (dma_params->mask->ssc_endx |
178 					dma_params->mask->ssc_endbuf);
179 			if (ssc_sr & ssc_substream_mask) {
180 				dma_params->dma_intr_handler(ssc_sr,
181 						dma_params->
182 						substream);
183 			}
184 		}
185 	}
186 
187 	return IRQ_HANDLED;
188 }
189 
190 /*
191  * When the bit clock is input, limit the maximum rate according to the
192  * Serial Clock Ratio Considerations section from the SSC documentation:
193  *
194  *   The Transmitter and the Receiver can be programmed to operate
195  *   with the clock signals provided on either the TK or RK pins.
196  *   This allows the SSC to support many slave-mode data transfers.
197  *   In this case, the maximum clock speed allowed on the RK pin is:
198  *   - Peripheral clock divided by 2 if Receiver Frame Synchro is input
199  *   - Peripheral clock divided by 3 if Receiver Frame Synchro is output
200  *   In addition, the maximum clock speed allowed on the TK pin is:
201  *   - Peripheral clock divided by 6 if Transmit Frame Synchro is input
202  *   - Peripheral clock divided by 2 if Transmit Frame Synchro is output
203  *
204  * When the bit clock is output, limit the rate according to the
205  * SSC divider restrictions.
206  */
207 static int atmel_ssc_hw_rule_rate(struct snd_pcm_hw_params *params,
208 				  struct snd_pcm_hw_rule *rule)
209 {
210 	struct atmel_ssc_info *ssc_p = rule->private;
211 	struct ssc_device *ssc = ssc_p->ssc;
212 	struct snd_interval *i = hw_param_interval(params, rule->var);
213 	struct snd_interval t;
214 	struct snd_ratnum r = {
215 		.den_min = 1,
216 		.den_max = 4095,
217 		.den_step = 1,
218 	};
219 	unsigned int num = 0, den = 0;
220 	int frame_size;
221 	int mck_div = 2;
222 	int ret;
223 
224 	frame_size = snd_soc_params_to_frame_size(params);
225 	if (frame_size < 0)
226 		return frame_size;
227 
228 	switch (ssc_p->daifmt & SND_SOC_DAIFMT_MASTER_MASK) {
229 	case SND_SOC_DAIFMT_CBM_CFS:
230 		if ((ssc_p->dir_mask & SSC_DIR_MASK_CAPTURE)
231 		    && ssc->clk_from_rk_pin)
232 			/* Receiver Frame Synchro (i.e. capture)
233 			 * is output (format is _CFS) and the RK pin
234 			 * is used for input (format is _CBM_).
235 			 */
236 			mck_div = 3;
237 		break;
238 
239 	case SND_SOC_DAIFMT_CBM_CFM:
240 		if ((ssc_p->dir_mask & SSC_DIR_MASK_PLAYBACK)
241 		    && !ssc->clk_from_rk_pin)
242 			/* Transmit Frame Synchro (i.e. playback)
243 			 * is input (format is _CFM) and the TK pin
244 			 * is used for input (format _CBM_ but not
245 			 * using the RK pin).
246 			 */
247 			mck_div = 6;
248 		break;
249 	}
250 
251 	switch (ssc_p->daifmt & SND_SOC_DAIFMT_MASTER_MASK) {
252 	case SND_SOC_DAIFMT_CBS_CFS:
253 		r.num = ssc_p->mck_rate / mck_div / frame_size;
254 
255 		ret = snd_interval_ratnum(i, 1, &r, &num, &den);
256 		if (ret >= 0 && den && rule->var == SNDRV_PCM_HW_PARAM_RATE) {
257 			params->rate_num = num;
258 			params->rate_den = den;
259 		}
260 		break;
261 
262 	case SND_SOC_DAIFMT_CBM_CFS:
263 	case SND_SOC_DAIFMT_CBM_CFM:
264 		t.min = 8000;
265 		t.max = ssc_p->mck_rate / mck_div / frame_size;
266 		t.openmin = t.openmax = 0;
267 		t.integer = 0;
268 		ret = snd_interval_refine(i, &t);
269 		break;
270 
271 	default:
272 		ret = -EINVAL;
273 		break;
274 	}
275 
276 	return ret;
277 }
278 
279 /*-------------------------------------------------------------------------*\
280  * DAI functions
281 \*-------------------------------------------------------------------------*/
282 /*
283  * Startup.  Only that one substream allowed in each direction.
284  */
285 static int atmel_ssc_startup(struct snd_pcm_substream *substream,
286 			     struct snd_soc_dai *dai)
287 {
288 	struct platform_device *pdev = to_platform_device(dai->dev);
289 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
290 	struct atmel_pcm_dma_params *dma_params;
291 	int dir, dir_mask;
292 	int ret;
293 
294 	pr_debug("atmel_ssc_startup: SSC_SR=0x%x\n",
295 		ssc_readl(ssc_p->ssc->regs, SR));
296 
297 	/* Enable PMC peripheral clock for this SSC */
298 	pr_debug("atmel_ssc_dai: Starting clock\n");
299 	clk_enable(ssc_p->ssc->clk);
300 	ssc_p->mck_rate = clk_get_rate(ssc_p->ssc->clk);
301 
302 	/* Reset the SSC unless initialized to keep it in a clean state */
303 	if (!ssc_p->initialized)
304 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
305 
306 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
307 		dir = 0;
308 		dir_mask = SSC_DIR_MASK_PLAYBACK;
309 	} else {
310 		dir = 1;
311 		dir_mask = SSC_DIR_MASK_CAPTURE;
312 	}
313 
314 	ret = snd_pcm_hw_rule_add(substream->runtime, 0,
315 				  SNDRV_PCM_HW_PARAM_RATE,
316 				  atmel_ssc_hw_rule_rate,
317 				  ssc_p,
318 				  SNDRV_PCM_HW_PARAM_FRAME_BITS,
319 				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
320 	if (ret < 0) {
321 		dev_err(dai->dev, "Failed to specify rate rule: %d\n", ret);
322 		return ret;
323 	}
324 
325 	dma_params = &ssc_dma_params[pdev->id][dir];
326 	dma_params->ssc = ssc_p->ssc;
327 	dma_params->substream = substream;
328 
329 	ssc_p->dma_params[dir] = dma_params;
330 
331 	snd_soc_dai_set_dma_data(dai, substream, dma_params);
332 
333 	spin_lock_irq(&ssc_p->lock);
334 	if (ssc_p->dir_mask & dir_mask) {
335 		spin_unlock_irq(&ssc_p->lock);
336 		return -EBUSY;
337 	}
338 	ssc_p->dir_mask |= dir_mask;
339 	spin_unlock_irq(&ssc_p->lock);
340 
341 	return 0;
342 }
343 
344 /*
345  * Shutdown.  Clear DMA parameters and shutdown the SSC if there
346  * are no other substreams open.
347  */
348 static void atmel_ssc_shutdown(struct snd_pcm_substream *substream,
349 			       struct snd_soc_dai *dai)
350 {
351 	struct platform_device *pdev = to_platform_device(dai->dev);
352 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
353 	struct atmel_pcm_dma_params *dma_params;
354 	int dir, dir_mask;
355 
356 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
357 		dir = 0;
358 	else
359 		dir = 1;
360 
361 	dma_params = ssc_p->dma_params[dir];
362 
363 	if (dma_params != NULL) {
364 		dma_params->ssc = NULL;
365 		dma_params->substream = NULL;
366 		ssc_p->dma_params[dir] = NULL;
367 	}
368 
369 	dir_mask = 1 << dir;
370 
371 	spin_lock_irq(&ssc_p->lock);
372 	ssc_p->dir_mask &= ~dir_mask;
373 	if (!ssc_p->dir_mask) {
374 		if (ssc_p->initialized) {
375 			free_irq(ssc_p->ssc->irq, ssc_p);
376 			ssc_p->initialized = 0;
377 		}
378 
379 		/* Reset the SSC */
380 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
381 		/* Clear the SSC dividers */
382 		ssc_p->cmr_div = ssc_p->tcmr_period = ssc_p->rcmr_period = 0;
383 	}
384 	spin_unlock_irq(&ssc_p->lock);
385 
386 	/* Shutdown the SSC clock. */
387 	pr_debug("atmel_ssc_dai: Stopping clock\n");
388 	clk_disable(ssc_p->ssc->clk);
389 }
390 
391 
392 /*
393  * Record the DAI format for use in hw_params().
394  */
395 static int atmel_ssc_set_dai_fmt(struct snd_soc_dai *cpu_dai,
396 		unsigned int fmt)
397 {
398 	struct platform_device *pdev = to_platform_device(cpu_dai->dev);
399 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
400 
401 	ssc_p->daifmt = fmt;
402 	return 0;
403 }
404 
405 /*
406  * Record SSC clock dividers for use in hw_params().
407  */
408 static int atmel_ssc_set_dai_clkdiv(struct snd_soc_dai *cpu_dai,
409 	int div_id, int div)
410 {
411 	struct platform_device *pdev = to_platform_device(cpu_dai->dev);
412 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
413 
414 	switch (div_id) {
415 	case ATMEL_SSC_CMR_DIV:
416 		/*
417 		 * The same master clock divider is used for both
418 		 * transmit and receive, so if a value has already
419 		 * been set, it must match this value.
420 		 */
421 		if (ssc_p->dir_mask !=
422 			(SSC_DIR_MASK_PLAYBACK | SSC_DIR_MASK_CAPTURE))
423 			ssc_p->cmr_div = div;
424 		else if (ssc_p->cmr_div == 0)
425 			ssc_p->cmr_div = div;
426 		else
427 			if (div != ssc_p->cmr_div)
428 				return -EBUSY;
429 		break;
430 
431 	case ATMEL_SSC_TCMR_PERIOD:
432 		ssc_p->tcmr_period = div;
433 		break;
434 
435 	case ATMEL_SSC_RCMR_PERIOD:
436 		ssc_p->rcmr_period = div;
437 		break;
438 
439 	default:
440 		return -EINVAL;
441 	}
442 
443 	return 0;
444 }
445 
446 /*
447  * Configure the SSC.
448  */
449 static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
450 	struct snd_pcm_hw_params *params,
451 	struct snd_soc_dai *dai)
452 {
453 	struct platform_device *pdev = to_platform_device(dai->dev);
454 	int id = pdev->id;
455 	struct atmel_ssc_info *ssc_p = &ssc_info[id];
456 	struct ssc_device *ssc = ssc_p->ssc;
457 	struct atmel_pcm_dma_params *dma_params;
458 	int dir, channels, bits;
459 	u32 tfmr, rfmr, tcmr, rcmr;
460 	int ret;
461 	int fslen, fslen_ext;
462 
463 	/*
464 	 * Currently, there is only one set of dma params for
465 	 * each direction.  If more are added, this code will
466 	 * have to be changed to select the proper set.
467 	 */
468 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
469 		dir = 0;
470 	else
471 		dir = 1;
472 
473 	dma_params = ssc_p->dma_params[dir];
474 
475 	channels = params_channels(params);
476 
477 	/*
478 	 * Determine sample size in bits and the PDC increment.
479 	 */
480 	switch (params_format(params)) {
481 	case SNDRV_PCM_FORMAT_S8:
482 		bits = 8;
483 		dma_params->pdc_xfer_size = 1;
484 		break;
485 	case SNDRV_PCM_FORMAT_S16_LE:
486 		bits = 16;
487 		dma_params->pdc_xfer_size = 2;
488 		break;
489 	case SNDRV_PCM_FORMAT_S24_LE:
490 		bits = 24;
491 		dma_params->pdc_xfer_size = 4;
492 		break;
493 	case SNDRV_PCM_FORMAT_S32_LE:
494 		bits = 32;
495 		dma_params->pdc_xfer_size = 4;
496 		break;
497 	default:
498 		printk(KERN_WARNING "atmel_ssc_dai: unsupported PCM format");
499 		return -EINVAL;
500 	}
501 
502 	/*
503 	 * Compute SSC register settings.
504 	 */
505 	switch (ssc_p->daifmt
506 		& (SND_SOC_DAIFMT_FORMAT_MASK | SND_SOC_DAIFMT_MASTER_MASK)) {
507 
508 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBS_CFS:
509 		/*
510 		 * I2S format, SSC provides BCLK and LRC clocks.
511 		 *
512 		 * The SSC transmit and receive clocks are generated
513 		 * from the MCK divider, and the BCLK signal
514 		 * is output on the SSC TK line.
515 		 */
516 
517 		if (bits > 16 && !ssc->pdata->has_fslen_ext) {
518 			dev_err(dai->dev,
519 				"sample size %d is too large for SSC device\n",
520 				bits);
521 			return -EINVAL;
522 		}
523 
524 		fslen_ext = (bits - 1) / 16;
525 		fslen = (bits - 1) % 16;
526 
527 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
528 			| SSC_BF(RCMR_STTDLY, START_DELAY)
529 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
530 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
531 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
532 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
533 
534 		rfmr =    SSC_BF(RFMR_FSLEN_EXT, fslen_ext)
535 			| SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
536 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NEGATIVE)
537 			| SSC_BF(RFMR_FSLEN, fslen)
538 			| SSC_BF(RFMR_DATNB, (channels - 1))
539 			| SSC_BIT(RFMR_MSBF)
540 			| SSC_BF(RFMR_LOOP, 0)
541 			| SSC_BF(RFMR_DATLEN, (bits - 1));
542 
543 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
544 			| SSC_BF(TCMR_STTDLY, START_DELAY)
545 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
546 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
547 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
548 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
549 
550 		tfmr =    SSC_BF(TFMR_FSLEN_EXT, fslen_ext)
551 			| SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
552 			| SSC_BF(TFMR_FSDEN, 0)
553 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NEGATIVE)
554 			| SSC_BF(TFMR_FSLEN, fslen)
555 			| SSC_BF(TFMR_DATNB, (channels - 1))
556 			| SSC_BIT(TFMR_MSBF)
557 			| SSC_BF(TFMR_DATDEF, 0)
558 			| SSC_BF(TFMR_DATLEN, (bits - 1));
559 		break;
560 
561 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBM_CFM:
562 		/* I2S format, CODEC supplies BCLK and LRC clocks. */
563 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
564 			| SSC_BF(RCMR_STTDLY, START_DELAY)
565 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
566 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
567 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
568 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
569 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
570 
571 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
572 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
573 			| SSC_BF(RFMR_FSLEN, 0)
574 			| SSC_BF(RFMR_DATNB, (channels - 1))
575 			| SSC_BIT(RFMR_MSBF)
576 			| SSC_BF(RFMR_LOOP, 0)
577 			| SSC_BF(RFMR_DATLEN, (bits - 1));
578 
579 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
580 			| SSC_BF(TCMR_STTDLY, START_DELAY)
581 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
582 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
583 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
584 			| SSC_BF(TCMR_CKS, ssc->clk_from_rk_pin ?
585 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
586 
587 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
588 			| SSC_BF(TFMR_FSDEN, 0)
589 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
590 			| SSC_BF(TFMR_FSLEN, 0)
591 			| SSC_BF(TFMR_DATNB, (channels - 1))
592 			| SSC_BIT(TFMR_MSBF)
593 			| SSC_BF(TFMR_DATDEF, 0)
594 			| SSC_BF(TFMR_DATLEN, (bits - 1));
595 		break;
596 
597 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBM_CFS:
598 		/* I2S format, CODEC supplies BCLK, SSC supplies LRCLK. */
599 		if (bits > 16 && !ssc->pdata->has_fslen_ext) {
600 			dev_err(dai->dev,
601 				"sample size %d is too large for SSC device\n",
602 				bits);
603 			return -EINVAL;
604 		}
605 
606 		fslen_ext = (bits - 1) / 16;
607 		fslen = (bits - 1) % 16;
608 
609 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
610 			| SSC_BF(RCMR_STTDLY, START_DELAY)
611 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
612 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
613 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
614 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
615 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
616 
617 		rfmr =    SSC_BF(RFMR_FSLEN_EXT, fslen_ext)
618 			| SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
619 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NEGATIVE)
620 			| SSC_BF(RFMR_FSLEN, fslen)
621 			| SSC_BF(RFMR_DATNB, (channels - 1))
622 			| SSC_BIT(RFMR_MSBF)
623 			| SSC_BF(RFMR_LOOP, 0)
624 			| SSC_BF(RFMR_DATLEN, (bits - 1));
625 
626 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
627 			| SSC_BF(TCMR_STTDLY, START_DELAY)
628 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
629 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
630 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
631 			| SSC_BF(TCMR_CKS, ssc->clk_from_rk_pin ?
632 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
633 
634 		tfmr =    SSC_BF(TFMR_FSLEN_EXT, fslen_ext)
635 			| SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_NEGATIVE)
636 			| SSC_BF(TFMR_FSDEN, 0)
637 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NEGATIVE)
638 			| SSC_BF(TFMR_FSLEN, fslen)
639 			| SSC_BF(TFMR_DATNB, (channels - 1))
640 			| SSC_BIT(TFMR_MSBF)
641 			| SSC_BF(TFMR_DATDEF, 0)
642 			| SSC_BF(TFMR_DATLEN, (bits - 1));
643 		break;
644 
645 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBS_CFS:
646 		/*
647 		 * DSP/PCM Mode A format, SSC provides BCLK and LRC clocks.
648 		 *
649 		 * The SSC transmit and receive clocks are generated from the
650 		 * MCK divider, and the BCLK signal is output
651 		 * on the SSC TK line.
652 		 */
653 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
654 			| SSC_BF(RCMR_STTDLY, 1)
655 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
656 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
657 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
658 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
659 
660 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
661 			| SSC_BF(RFMR_FSOS, SSC_FSOS_POSITIVE)
662 			| SSC_BF(RFMR_FSLEN, 0)
663 			| SSC_BF(RFMR_DATNB, (channels - 1))
664 			| SSC_BIT(RFMR_MSBF)
665 			| SSC_BF(RFMR_LOOP, 0)
666 			| SSC_BF(RFMR_DATLEN, (bits - 1));
667 
668 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
669 			| SSC_BF(TCMR_STTDLY, 1)
670 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
671 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
672 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
673 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
674 
675 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
676 			| SSC_BF(TFMR_FSDEN, 0)
677 			| SSC_BF(TFMR_FSOS, SSC_FSOS_POSITIVE)
678 			| SSC_BF(TFMR_FSLEN, 0)
679 			| SSC_BF(TFMR_DATNB, (channels - 1))
680 			| SSC_BIT(TFMR_MSBF)
681 			| SSC_BF(TFMR_DATDEF, 0)
682 			| SSC_BF(TFMR_DATLEN, (bits - 1));
683 		break;
684 
685 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBM_CFM:
686 		/*
687 		 * DSP/PCM Mode A format, CODEC supplies BCLK and LRC clocks.
688 		 *
689 		 * Data is transferred on first BCLK after LRC pulse rising
690 		 * edge.If stereo, the right channel data is contiguous with
691 		 * the left channel data.
692 		 */
693 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
694 			| SSC_BF(RCMR_STTDLY, START_DELAY)
695 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
696 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
697 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
698 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
699 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
700 
701 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
702 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
703 			| SSC_BF(RFMR_FSLEN, 0)
704 			| SSC_BF(RFMR_DATNB, (channels - 1))
705 			| SSC_BIT(RFMR_MSBF)
706 			| SSC_BF(RFMR_LOOP, 0)
707 			| SSC_BF(RFMR_DATLEN, (bits - 1));
708 
709 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
710 			| SSC_BF(TCMR_STTDLY, START_DELAY)
711 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
712 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
713 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
714 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
715 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
716 
717 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
718 			| SSC_BF(TFMR_FSDEN, 0)
719 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
720 			| SSC_BF(TFMR_FSLEN, 0)
721 			| SSC_BF(TFMR_DATNB, (channels - 1))
722 			| SSC_BIT(TFMR_MSBF)
723 			| SSC_BF(TFMR_DATDEF, 0)
724 			| SSC_BF(TFMR_DATLEN, (bits - 1));
725 		break;
726 
727 	default:
728 		printk(KERN_WARNING "atmel_ssc_dai: unsupported DAI format 0x%x\n",
729 			ssc_p->daifmt);
730 		return -EINVAL;
731 	}
732 	pr_debug("atmel_ssc_hw_params: "
733 			"RCMR=%08x RFMR=%08x TCMR=%08x TFMR=%08x\n",
734 			rcmr, rfmr, tcmr, tfmr);
735 
736 	if (!ssc_p->initialized) {
737 		if (!ssc_p->ssc->pdata->use_dma) {
738 			ssc_writel(ssc_p->ssc->regs, PDC_RPR, 0);
739 			ssc_writel(ssc_p->ssc->regs, PDC_RCR, 0);
740 			ssc_writel(ssc_p->ssc->regs, PDC_RNPR, 0);
741 			ssc_writel(ssc_p->ssc->regs, PDC_RNCR, 0);
742 
743 			ssc_writel(ssc_p->ssc->regs, PDC_TPR, 0);
744 			ssc_writel(ssc_p->ssc->regs, PDC_TCR, 0);
745 			ssc_writel(ssc_p->ssc->regs, PDC_TNPR, 0);
746 			ssc_writel(ssc_p->ssc->regs, PDC_TNCR, 0);
747 		}
748 
749 		ret = request_irq(ssc_p->ssc->irq, atmel_ssc_interrupt, 0,
750 				ssc_p->name, ssc_p);
751 		if (ret < 0) {
752 			printk(KERN_WARNING
753 					"atmel_ssc_dai: request_irq failure\n");
754 			pr_debug("Atmel_ssc_dai: Stoping clock\n");
755 			clk_disable(ssc_p->ssc->clk);
756 			return ret;
757 		}
758 
759 		ssc_p->initialized = 1;
760 	}
761 
762 	/* set SSC clock mode register */
763 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->cmr_div);
764 
765 	/* set receive clock mode and format */
766 	ssc_writel(ssc_p->ssc->regs, RCMR, rcmr);
767 	ssc_writel(ssc_p->ssc->regs, RFMR, rfmr);
768 
769 	/* set transmit clock mode and format */
770 	ssc_writel(ssc_p->ssc->regs, TCMR, tcmr);
771 	ssc_writel(ssc_p->ssc->regs, TFMR, tfmr);
772 
773 	pr_debug("atmel_ssc_dai,hw_params: SSC initialized\n");
774 	return 0;
775 }
776 
777 
778 static int atmel_ssc_prepare(struct snd_pcm_substream *substream,
779 			     struct snd_soc_dai *dai)
780 {
781 	struct platform_device *pdev = to_platform_device(dai->dev);
782 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
783 	struct atmel_pcm_dma_params *dma_params;
784 	int dir;
785 
786 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
787 		dir = 0;
788 	else
789 		dir = 1;
790 
791 	dma_params = ssc_p->dma_params[dir];
792 
793 	ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
794 	ssc_writel(ssc_p->ssc->regs, IDR, dma_params->mask->ssc_error);
795 
796 	pr_debug("%s enabled SSC_SR=0x%08x\n",
797 			dir ? "receive" : "transmit",
798 			ssc_readl(ssc_p->ssc->regs, SR));
799 	return 0;
800 }
801 
802 static int atmel_ssc_trigger(struct snd_pcm_substream *substream,
803 			     int cmd, struct snd_soc_dai *dai)
804 {
805 	struct platform_device *pdev = to_platform_device(dai->dev);
806 	struct atmel_ssc_info *ssc_p = &ssc_info[pdev->id];
807 	struct atmel_pcm_dma_params *dma_params;
808 	int dir;
809 
810 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
811 		dir = 0;
812 	else
813 		dir = 1;
814 
815 	dma_params = ssc_p->dma_params[dir];
816 
817 	switch (cmd) {
818 	case SNDRV_PCM_TRIGGER_START:
819 	case SNDRV_PCM_TRIGGER_RESUME:
820 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
821 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_enable);
822 		break;
823 	default:
824 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
825 		break;
826 	}
827 
828 	return 0;
829 }
830 
831 #ifdef CONFIG_PM
832 static int atmel_ssc_suspend(struct snd_soc_dai *cpu_dai)
833 {
834 	struct atmel_ssc_info *ssc_p;
835 	struct platform_device *pdev = to_platform_device(cpu_dai->dev);
836 
837 	if (!cpu_dai->active)
838 		return 0;
839 
840 	ssc_p = &ssc_info[pdev->id];
841 
842 	/* Save the status register before disabling transmit and receive */
843 	ssc_p->ssc_state.ssc_sr = ssc_readl(ssc_p->ssc->regs, SR);
844 	ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_TXDIS) | SSC_BIT(CR_RXDIS));
845 
846 	/* Save the current interrupt mask, then disable unmasked interrupts */
847 	ssc_p->ssc_state.ssc_imr = ssc_readl(ssc_p->ssc->regs, IMR);
848 	ssc_writel(ssc_p->ssc->regs, IDR, ssc_p->ssc_state.ssc_imr);
849 
850 	ssc_p->ssc_state.ssc_cmr = ssc_readl(ssc_p->ssc->regs, CMR);
851 	ssc_p->ssc_state.ssc_rcmr = ssc_readl(ssc_p->ssc->regs, RCMR);
852 	ssc_p->ssc_state.ssc_rfmr = ssc_readl(ssc_p->ssc->regs, RFMR);
853 	ssc_p->ssc_state.ssc_tcmr = ssc_readl(ssc_p->ssc->regs, TCMR);
854 	ssc_p->ssc_state.ssc_tfmr = ssc_readl(ssc_p->ssc->regs, TFMR);
855 
856 	return 0;
857 }
858 
859 
860 
861 static int atmel_ssc_resume(struct snd_soc_dai *cpu_dai)
862 {
863 	struct atmel_ssc_info *ssc_p;
864 	struct platform_device *pdev = to_platform_device(cpu_dai->dev);
865 	u32 cr;
866 
867 	if (!cpu_dai->active)
868 		return 0;
869 
870 	ssc_p = &ssc_info[pdev->id];
871 
872 	/* restore SSC register settings */
873 	ssc_writel(ssc_p->ssc->regs, TFMR, ssc_p->ssc_state.ssc_tfmr);
874 	ssc_writel(ssc_p->ssc->regs, TCMR, ssc_p->ssc_state.ssc_tcmr);
875 	ssc_writel(ssc_p->ssc->regs, RFMR, ssc_p->ssc_state.ssc_rfmr);
876 	ssc_writel(ssc_p->ssc->regs, RCMR, ssc_p->ssc_state.ssc_rcmr);
877 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->ssc_state.ssc_cmr);
878 
879 	/* re-enable interrupts */
880 	ssc_writel(ssc_p->ssc->regs, IER, ssc_p->ssc_state.ssc_imr);
881 
882 	/* Re-enable receive and transmit as appropriate */
883 	cr = 0;
884 	cr |=
885 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_RXEN)) ? SSC_BIT(CR_RXEN) : 0;
886 	cr |=
887 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_TXEN)) ? SSC_BIT(CR_TXEN) : 0;
888 	ssc_writel(ssc_p->ssc->regs, CR, cr);
889 
890 	return 0;
891 }
892 #else /* CONFIG_PM */
893 #  define atmel_ssc_suspend	NULL
894 #  define atmel_ssc_resume	NULL
895 #endif /* CONFIG_PM */
896 
897 #define ATMEL_SSC_FORMATS (SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_S16_LE |\
898 			  SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
899 
900 static const struct snd_soc_dai_ops atmel_ssc_dai_ops = {
901 	.startup	= atmel_ssc_startup,
902 	.shutdown	= atmel_ssc_shutdown,
903 	.prepare	= atmel_ssc_prepare,
904 	.trigger	= atmel_ssc_trigger,
905 	.hw_params	= atmel_ssc_hw_params,
906 	.set_fmt	= atmel_ssc_set_dai_fmt,
907 	.set_clkdiv	= atmel_ssc_set_dai_clkdiv,
908 };
909 
910 static struct snd_soc_dai_driver atmel_ssc_dai = {
911 		.suspend = atmel_ssc_suspend,
912 		.resume = atmel_ssc_resume,
913 		.playback = {
914 			.channels_min = 1,
915 			.channels_max = 2,
916 			.rates = SNDRV_PCM_RATE_CONTINUOUS,
917 			.rate_min = 8000,
918 			.rate_max = 384000,
919 			.formats = ATMEL_SSC_FORMATS,},
920 		.capture = {
921 			.channels_min = 1,
922 			.channels_max = 2,
923 			.rates = SNDRV_PCM_RATE_CONTINUOUS,
924 			.rate_min = 8000,
925 			.rate_max = 384000,
926 			.formats = ATMEL_SSC_FORMATS,},
927 		.ops = &atmel_ssc_dai_ops,
928 };
929 
930 static const struct snd_soc_component_driver atmel_ssc_component = {
931 	.name		= "atmel-ssc",
932 };
933 
934 static int asoc_ssc_init(struct device *dev)
935 {
936 	struct platform_device *pdev = to_platform_device(dev);
937 	struct ssc_device *ssc = platform_get_drvdata(pdev);
938 	int ret;
939 
940 	ret = snd_soc_register_component(dev, &atmel_ssc_component,
941 					 &atmel_ssc_dai, 1);
942 	if (ret) {
943 		dev_err(dev, "Could not register DAI: %d\n", ret);
944 		goto err;
945 	}
946 
947 	if (ssc->pdata->use_dma)
948 		ret = atmel_pcm_dma_platform_register(dev);
949 	else
950 		ret = atmel_pcm_pdc_platform_register(dev);
951 
952 	if (ret) {
953 		dev_err(dev, "Could not register PCM: %d\n", ret);
954 		goto err_unregister_dai;
955 	}
956 
957 	return 0;
958 
959 err_unregister_dai:
960 	snd_soc_unregister_component(dev);
961 err:
962 	return ret;
963 }
964 
965 static void asoc_ssc_exit(struct device *dev)
966 {
967 	struct platform_device *pdev = to_platform_device(dev);
968 	struct ssc_device *ssc = platform_get_drvdata(pdev);
969 
970 	if (ssc->pdata->use_dma)
971 		atmel_pcm_dma_platform_unregister(dev);
972 	else
973 		atmel_pcm_pdc_platform_unregister(dev);
974 
975 	snd_soc_unregister_component(dev);
976 }
977 
978 /**
979  * atmel_ssc_set_audio - Allocate the specified SSC for audio use.
980  */
981 int atmel_ssc_set_audio(int ssc_id)
982 {
983 	struct ssc_device *ssc;
984 	int ret;
985 
986 	/* If we can grab the SSC briefly to parent the DAI device off it */
987 	ssc = ssc_request(ssc_id);
988 	if (IS_ERR(ssc)) {
989 		pr_err("Unable to parent ASoC SSC DAI on SSC: %ld\n",
990 			PTR_ERR(ssc));
991 		return PTR_ERR(ssc);
992 	} else {
993 		ssc_info[ssc_id].ssc = ssc;
994 	}
995 
996 	ret = asoc_ssc_init(&ssc->pdev->dev);
997 
998 	return ret;
999 }
1000 EXPORT_SYMBOL_GPL(atmel_ssc_set_audio);
1001 
1002 void atmel_ssc_put_audio(int ssc_id)
1003 {
1004 	struct ssc_device *ssc = ssc_info[ssc_id].ssc;
1005 
1006 	asoc_ssc_exit(&ssc->pdev->dev);
1007 	ssc_free(ssc);
1008 }
1009 EXPORT_SYMBOL_GPL(atmel_ssc_put_audio);
1010 
1011 /* Module information */
1012 MODULE_AUTHOR("Sedji Gaouaou, sedji.gaouaou@atmel.com, www.atmel.com");
1013 MODULE_DESCRIPTION("ATMEL SSC ASoC Interface");
1014 MODULE_LICENSE("GPL");
1015