xref: /openbmc/linux/sound/soc/atmel/atmel_ssc_dai.c (revision c819e2cf)
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 /*-------------------------------------------------------------------------*\
192  * DAI functions
193 \*-------------------------------------------------------------------------*/
194 /*
195  * Startup.  Only that one substream allowed in each direction.
196  */
197 static int atmel_ssc_startup(struct snd_pcm_substream *substream,
198 			     struct snd_soc_dai *dai)
199 {
200 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
201 	struct atmel_pcm_dma_params *dma_params;
202 	int dir, dir_mask;
203 
204 	pr_debug("atmel_ssc_startup: SSC_SR=0x%u\n",
205 		ssc_readl(ssc_p->ssc->regs, SR));
206 
207 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
208 		dir = 0;
209 		dir_mask = SSC_DIR_MASK_PLAYBACK;
210 	} else {
211 		dir = 1;
212 		dir_mask = SSC_DIR_MASK_CAPTURE;
213 	}
214 
215 	dma_params = &ssc_dma_params[dai->id][dir];
216 	dma_params->ssc = ssc_p->ssc;
217 	dma_params->substream = substream;
218 
219 	ssc_p->dma_params[dir] = dma_params;
220 
221 	snd_soc_dai_set_dma_data(dai, substream, dma_params);
222 
223 	spin_lock_irq(&ssc_p->lock);
224 	if (ssc_p->dir_mask & dir_mask) {
225 		spin_unlock_irq(&ssc_p->lock);
226 		return -EBUSY;
227 	}
228 	ssc_p->dir_mask |= dir_mask;
229 	spin_unlock_irq(&ssc_p->lock);
230 
231 	return 0;
232 }
233 
234 /*
235  * Shutdown.  Clear DMA parameters and shutdown the SSC if there
236  * are no other substreams open.
237  */
238 static void atmel_ssc_shutdown(struct snd_pcm_substream *substream,
239 			       struct snd_soc_dai *dai)
240 {
241 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
242 	struct atmel_pcm_dma_params *dma_params;
243 	int dir, dir_mask;
244 
245 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
246 		dir = 0;
247 	else
248 		dir = 1;
249 
250 	dma_params = ssc_p->dma_params[dir];
251 
252 	if (dma_params != NULL) {
253 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
254 		pr_debug("atmel_ssc_shutdown: %s disabled SSC_SR=0x%08x\n",
255 			(dir ? "receive" : "transmit"),
256 			ssc_readl(ssc_p->ssc->regs, SR));
257 
258 		dma_params->ssc = NULL;
259 		dma_params->substream = NULL;
260 		ssc_p->dma_params[dir] = NULL;
261 	}
262 
263 	dir_mask = 1 << dir;
264 
265 	spin_lock_irq(&ssc_p->lock);
266 	ssc_p->dir_mask &= ~dir_mask;
267 	if (!ssc_p->dir_mask) {
268 		if (ssc_p->initialized) {
269 			/* Shutdown the SSC clock. */
270 			pr_debug("atmel_ssc_dai: Stopping clock\n");
271 			clk_disable(ssc_p->ssc->clk);
272 
273 			free_irq(ssc_p->ssc->irq, ssc_p);
274 			ssc_p->initialized = 0;
275 		}
276 
277 		/* Reset the SSC */
278 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
279 		/* Clear the SSC dividers */
280 		ssc_p->cmr_div = ssc_p->tcmr_period = ssc_p->rcmr_period = 0;
281 	}
282 	spin_unlock_irq(&ssc_p->lock);
283 }
284 
285 
286 /*
287  * Record the DAI format for use in hw_params().
288  */
289 static int atmel_ssc_set_dai_fmt(struct snd_soc_dai *cpu_dai,
290 		unsigned int fmt)
291 {
292 	struct atmel_ssc_info *ssc_p = &ssc_info[cpu_dai->id];
293 
294 	ssc_p->daifmt = fmt;
295 	return 0;
296 }
297 
298 /*
299  * Record SSC clock dividers for use in hw_params().
300  */
301 static int atmel_ssc_set_dai_clkdiv(struct snd_soc_dai *cpu_dai,
302 	int div_id, int div)
303 {
304 	struct atmel_ssc_info *ssc_p = &ssc_info[cpu_dai->id];
305 
306 	switch (div_id) {
307 	case ATMEL_SSC_CMR_DIV:
308 		/*
309 		 * The same master clock divider is used for both
310 		 * transmit and receive, so if a value has already
311 		 * been set, it must match this value.
312 		 */
313 		if (ssc_p->dir_mask !=
314 			(SSC_DIR_MASK_PLAYBACK | SSC_DIR_MASK_CAPTURE))
315 			ssc_p->cmr_div = div;
316 		else if (ssc_p->cmr_div == 0)
317 			ssc_p->cmr_div = div;
318 		else
319 			if (div != ssc_p->cmr_div)
320 				return -EBUSY;
321 		break;
322 
323 	case ATMEL_SSC_TCMR_PERIOD:
324 		ssc_p->tcmr_period = div;
325 		break;
326 
327 	case ATMEL_SSC_RCMR_PERIOD:
328 		ssc_p->rcmr_period = div;
329 		break;
330 
331 	default:
332 		return -EINVAL;
333 	}
334 
335 	return 0;
336 }
337 
338 /*
339  * Configure the SSC.
340  */
341 static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
342 	struct snd_pcm_hw_params *params,
343 	struct snd_soc_dai *dai)
344 {
345 	int id = dai->id;
346 	struct atmel_ssc_info *ssc_p = &ssc_info[id];
347 	struct ssc_device *ssc = ssc_p->ssc;
348 	struct atmel_pcm_dma_params *dma_params;
349 	int dir, channels, bits;
350 	u32 tfmr, rfmr, tcmr, rcmr;
351 	int start_event;
352 	int ret;
353 	int fslen, fslen_ext;
354 
355 	/*
356 	 * Currently, there is only one set of dma params for
357 	 * each direction.  If more are added, this code will
358 	 * have to be changed to select the proper set.
359 	 */
360 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
361 		dir = 0;
362 	else
363 		dir = 1;
364 
365 	dma_params = ssc_p->dma_params[dir];
366 
367 	channels = params_channels(params);
368 
369 	/*
370 	 * Determine sample size in bits and the PDC increment.
371 	 */
372 	switch (params_format(params)) {
373 	case SNDRV_PCM_FORMAT_S8:
374 		bits = 8;
375 		dma_params->pdc_xfer_size = 1;
376 		break;
377 	case SNDRV_PCM_FORMAT_S16_LE:
378 		bits = 16;
379 		dma_params->pdc_xfer_size = 2;
380 		break;
381 	case SNDRV_PCM_FORMAT_S24_LE:
382 		bits = 24;
383 		dma_params->pdc_xfer_size = 4;
384 		break;
385 	case SNDRV_PCM_FORMAT_S32_LE:
386 		bits = 32;
387 		dma_params->pdc_xfer_size = 4;
388 		break;
389 	default:
390 		printk(KERN_WARNING "atmel_ssc_dai: unsupported PCM format");
391 		return -EINVAL;
392 	}
393 
394 	/*
395 	 * Compute SSC register settings.
396 	 */
397 	switch (ssc_p->daifmt
398 		& (SND_SOC_DAIFMT_FORMAT_MASK | SND_SOC_DAIFMT_MASTER_MASK)) {
399 
400 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBS_CFS:
401 		/*
402 		 * I2S format, SSC provides BCLK and LRC clocks.
403 		 *
404 		 * The SSC transmit and receive clocks are generated
405 		 * from the MCK divider, and the BCLK signal
406 		 * is output on the SSC TK line.
407 		 */
408 
409 		if (bits > 16 && !ssc->pdata->has_fslen_ext) {
410 			dev_err(dai->dev,
411 				"sample size %d is too large for SSC device\n",
412 				bits);
413 			return -EINVAL;
414 		}
415 
416 		fslen_ext = (bits - 1) / 16;
417 		fslen = (bits - 1) % 16;
418 
419 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
420 			| SSC_BF(RCMR_STTDLY, START_DELAY)
421 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
422 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
423 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
424 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
425 
426 		rfmr =    SSC_BF(RFMR_FSLEN_EXT, fslen_ext)
427 			| SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
428 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NEGATIVE)
429 			| SSC_BF(RFMR_FSLEN, fslen)
430 			| SSC_BF(RFMR_DATNB, (channels - 1))
431 			| SSC_BIT(RFMR_MSBF)
432 			| SSC_BF(RFMR_LOOP, 0)
433 			| SSC_BF(RFMR_DATLEN, (bits - 1));
434 
435 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
436 			| SSC_BF(TCMR_STTDLY, START_DELAY)
437 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
438 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
439 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
440 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
441 
442 		tfmr =    SSC_BF(TFMR_FSLEN_EXT, fslen_ext)
443 			| SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
444 			| SSC_BF(TFMR_FSDEN, 0)
445 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NEGATIVE)
446 			| SSC_BF(TFMR_FSLEN, fslen)
447 			| SSC_BF(TFMR_DATNB, (channels - 1))
448 			| SSC_BIT(TFMR_MSBF)
449 			| SSC_BF(TFMR_DATDEF, 0)
450 			| SSC_BF(TFMR_DATLEN, (bits - 1));
451 		break;
452 
453 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBM_CFM:
454 		/*
455 		 * I2S format, CODEC supplies BCLK and LRC clocks.
456 		 *
457 		 * The SSC transmit clock is obtained from the BCLK signal on
458 		 * on the TK line, and the SSC receive clock is
459 		 * generated from the transmit clock.
460 		 *
461 		 *  For single channel data, one sample is transferred
462 		 * on the falling edge of the LRC clock.
463 		 * For two channel data, one sample is
464 		 * transferred on both edges of the LRC clock.
465 		 */
466 		start_event = ((channels == 1)
467 				? SSC_START_FALLING_RF
468 				: SSC_START_EDGE_RF);
469 
470 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
471 			| SSC_BF(RCMR_STTDLY, START_DELAY)
472 			| SSC_BF(RCMR_START, start_event)
473 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
474 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
475 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
476 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
477 
478 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
479 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
480 			| SSC_BF(RFMR_FSLEN, 0)
481 			| SSC_BF(RFMR_DATNB, 0)
482 			| SSC_BIT(RFMR_MSBF)
483 			| SSC_BF(RFMR_LOOP, 0)
484 			| SSC_BF(RFMR_DATLEN, (bits - 1));
485 
486 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
487 			| SSC_BF(TCMR_STTDLY, START_DELAY)
488 			| SSC_BF(TCMR_START, start_event)
489 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
490 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
491 			| SSC_BF(TCMR_CKS, ssc->clk_from_rk_pin ?
492 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
493 
494 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
495 			| SSC_BF(TFMR_FSDEN, 0)
496 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
497 			| SSC_BF(TFMR_FSLEN, 0)
498 			| SSC_BF(TFMR_DATNB, 0)
499 			| SSC_BIT(TFMR_MSBF)
500 			| SSC_BF(TFMR_DATDEF, 0)
501 			| SSC_BF(TFMR_DATLEN, (bits - 1));
502 		break;
503 
504 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBS_CFS:
505 		/*
506 		 * DSP/PCM Mode A format, SSC provides BCLK and LRC clocks.
507 		 *
508 		 * The SSC transmit and receive clocks are generated from the
509 		 * MCK divider, and the BCLK signal is output
510 		 * on the SSC TK line.
511 		 */
512 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
513 			| SSC_BF(RCMR_STTDLY, 1)
514 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
515 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
516 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
517 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
518 
519 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
520 			| SSC_BF(RFMR_FSOS, SSC_FSOS_POSITIVE)
521 			| SSC_BF(RFMR_FSLEN, 0)
522 			| SSC_BF(RFMR_DATNB, (channels - 1))
523 			| SSC_BIT(RFMR_MSBF)
524 			| SSC_BF(RFMR_LOOP, 0)
525 			| SSC_BF(RFMR_DATLEN, (bits - 1));
526 
527 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
528 			| SSC_BF(TCMR_STTDLY, 1)
529 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
530 			| SSC_BF(TCMR_CKI, SSC_CKI_RISING)
531 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
532 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
533 
534 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
535 			| SSC_BF(TFMR_FSDEN, 0)
536 			| SSC_BF(TFMR_FSOS, SSC_FSOS_POSITIVE)
537 			| SSC_BF(TFMR_FSLEN, 0)
538 			| SSC_BF(TFMR_DATNB, (channels - 1))
539 			| SSC_BIT(TFMR_MSBF)
540 			| SSC_BF(TFMR_DATDEF, 0)
541 			| SSC_BF(TFMR_DATLEN, (bits - 1));
542 		break;
543 
544 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBM_CFM:
545 		/*
546 		 * DSP/PCM Mode A format, CODEC supplies BCLK and LRC clocks.
547 		 *
548 		 * The SSC transmit clock is obtained from the BCLK signal on
549 		 * on the TK line, and the SSC receive clock is
550 		 * generated from the transmit clock.
551 		 *
552 		 * Data is transferred on first BCLK after LRC pulse rising
553 		 * edge.If stereo, the right channel data is contiguous with
554 		 * the left channel data.
555 		 */
556 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
557 			| SSC_BF(RCMR_STTDLY, START_DELAY)
558 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
559 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
560 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
561 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
562 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
563 
564 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
565 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
566 			| SSC_BF(RFMR_FSLEN, 0)
567 			| SSC_BF(RFMR_DATNB, (channels - 1))
568 			| SSC_BIT(RFMR_MSBF)
569 			| SSC_BF(RFMR_LOOP, 0)
570 			| SSC_BF(RFMR_DATLEN, (bits - 1));
571 
572 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
573 			| SSC_BF(TCMR_STTDLY, START_DELAY)
574 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
575 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
576 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
577 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
578 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
579 
580 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
581 			| SSC_BF(TFMR_FSDEN, 0)
582 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
583 			| SSC_BF(TFMR_FSLEN, 0)
584 			| SSC_BF(TFMR_DATNB, (channels - 1))
585 			| SSC_BIT(TFMR_MSBF)
586 			| SSC_BF(TFMR_DATDEF, 0)
587 			| SSC_BF(TFMR_DATLEN, (bits - 1));
588 		break;
589 
590 	default:
591 		printk(KERN_WARNING "atmel_ssc_dai: unsupported DAI format 0x%x\n",
592 			ssc_p->daifmt);
593 		return -EINVAL;
594 	}
595 	pr_debug("atmel_ssc_hw_params: "
596 			"RCMR=%08x RFMR=%08x TCMR=%08x TFMR=%08x\n",
597 			rcmr, rfmr, tcmr, tfmr);
598 
599 	if (!ssc_p->initialized) {
600 
601 		/* Enable PMC peripheral clock for this SSC */
602 		pr_debug("atmel_ssc_dai: Starting clock\n");
603 		clk_enable(ssc_p->ssc->clk);
604 
605 		/* Reset the SSC and its PDC registers */
606 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
607 
608 		ssc_writel(ssc_p->ssc->regs, PDC_RPR, 0);
609 		ssc_writel(ssc_p->ssc->regs, PDC_RCR, 0);
610 		ssc_writel(ssc_p->ssc->regs, PDC_RNPR, 0);
611 		ssc_writel(ssc_p->ssc->regs, PDC_RNCR, 0);
612 
613 		ssc_writel(ssc_p->ssc->regs, PDC_TPR, 0);
614 		ssc_writel(ssc_p->ssc->regs, PDC_TCR, 0);
615 		ssc_writel(ssc_p->ssc->regs, PDC_TNPR, 0);
616 		ssc_writel(ssc_p->ssc->regs, PDC_TNCR, 0);
617 
618 		ret = request_irq(ssc_p->ssc->irq, atmel_ssc_interrupt, 0,
619 				ssc_p->name, ssc_p);
620 		if (ret < 0) {
621 			printk(KERN_WARNING
622 					"atmel_ssc_dai: request_irq failure\n");
623 			pr_debug("Atmel_ssc_dai: Stoping clock\n");
624 			clk_disable(ssc_p->ssc->clk);
625 			return ret;
626 		}
627 
628 		ssc_p->initialized = 1;
629 	}
630 
631 	/* set SSC clock mode register */
632 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->cmr_div);
633 
634 	/* set receive clock mode and format */
635 	ssc_writel(ssc_p->ssc->regs, RCMR, rcmr);
636 	ssc_writel(ssc_p->ssc->regs, RFMR, rfmr);
637 
638 	/* set transmit clock mode and format */
639 	ssc_writel(ssc_p->ssc->regs, TCMR, tcmr);
640 	ssc_writel(ssc_p->ssc->regs, TFMR, tfmr);
641 
642 	pr_debug("atmel_ssc_dai,hw_params: SSC initialized\n");
643 	return 0;
644 }
645 
646 
647 static int atmel_ssc_prepare(struct snd_pcm_substream *substream,
648 			     struct snd_soc_dai *dai)
649 {
650 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
651 	struct atmel_pcm_dma_params *dma_params;
652 	int dir;
653 
654 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
655 		dir = 0;
656 	else
657 		dir = 1;
658 
659 	dma_params = ssc_p->dma_params[dir];
660 
661 	ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
662 	ssc_writel(ssc_p->ssc->regs, IDR, dma_params->mask->ssc_error);
663 
664 	pr_debug("%s enabled SSC_SR=0x%08x\n",
665 			dir ? "receive" : "transmit",
666 			ssc_readl(ssc_p->ssc->regs, SR));
667 	return 0;
668 }
669 
670 static int atmel_ssc_trigger(struct snd_pcm_substream *substream,
671 			     int cmd, struct snd_soc_dai *dai)
672 {
673 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
674 	struct atmel_pcm_dma_params *dma_params;
675 	int dir;
676 
677 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
678 		dir = 0;
679 	else
680 		dir = 1;
681 
682 	dma_params = ssc_p->dma_params[dir];
683 
684 	switch (cmd) {
685 	case SNDRV_PCM_TRIGGER_START:
686 	case SNDRV_PCM_TRIGGER_RESUME:
687 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
688 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_enable);
689 		break;
690 	default:
691 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
692 		break;
693 	}
694 
695 	return 0;
696 }
697 
698 #ifdef CONFIG_PM
699 static int atmel_ssc_suspend(struct snd_soc_dai *cpu_dai)
700 {
701 	struct atmel_ssc_info *ssc_p;
702 
703 	if (!cpu_dai->active)
704 		return 0;
705 
706 	ssc_p = &ssc_info[cpu_dai->id];
707 
708 	/* Save the status register before disabling transmit and receive */
709 	ssc_p->ssc_state.ssc_sr = ssc_readl(ssc_p->ssc->regs, SR);
710 	ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_TXDIS) | SSC_BIT(CR_RXDIS));
711 
712 	/* Save the current interrupt mask, then disable unmasked interrupts */
713 	ssc_p->ssc_state.ssc_imr = ssc_readl(ssc_p->ssc->regs, IMR);
714 	ssc_writel(ssc_p->ssc->regs, IDR, ssc_p->ssc_state.ssc_imr);
715 
716 	ssc_p->ssc_state.ssc_cmr = ssc_readl(ssc_p->ssc->regs, CMR);
717 	ssc_p->ssc_state.ssc_rcmr = ssc_readl(ssc_p->ssc->regs, RCMR);
718 	ssc_p->ssc_state.ssc_rfmr = ssc_readl(ssc_p->ssc->regs, RFMR);
719 	ssc_p->ssc_state.ssc_tcmr = ssc_readl(ssc_p->ssc->regs, TCMR);
720 	ssc_p->ssc_state.ssc_tfmr = ssc_readl(ssc_p->ssc->regs, TFMR);
721 
722 	return 0;
723 }
724 
725 
726 
727 static int atmel_ssc_resume(struct snd_soc_dai *cpu_dai)
728 {
729 	struct atmel_ssc_info *ssc_p;
730 	u32 cr;
731 
732 	if (!cpu_dai->active)
733 		return 0;
734 
735 	ssc_p = &ssc_info[cpu_dai->id];
736 
737 	/* restore SSC register settings */
738 	ssc_writel(ssc_p->ssc->regs, TFMR, ssc_p->ssc_state.ssc_tfmr);
739 	ssc_writel(ssc_p->ssc->regs, TCMR, ssc_p->ssc_state.ssc_tcmr);
740 	ssc_writel(ssc_p->ssc->regs, RFMR, ssc_p->ssc_state.ssc_rfmr);
741 	ssc_writel(ssc_p->ssc->regs, RCMR, ssc_p->ssc_state.ssc_rcmr);
742 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->ssc_state.ssc_cmr);
743 
744 	/* re-enable interrupts */
745 	ssc_writel(ssc_p->ssc->regs, IER, ssc_p->ssc_state.ssc_imr);
746 
747 	/* Re-enable receive and transmit as appropriate */
748 	cr = 0;
749 	cr |=
750 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_RXEN)) ? SSC_BIT(CR_RXEN) : 0;
751 	cr |=
752 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_TXEN)) ? SSC_BIT(CR_TXEN) : 0;
753 	ssc_writel(ssc_p->ssc->regs, CR, cr);
754 
755 	return 0;
756 }
757 #else /* CONFIG_PM */
758 #  define atmel_ssc_suspend	NULL
759 #  define atmel_ssc_resume	NULL
760 #endif /* CONFIG_PM */
761 
762 #define ATMEL_SSC_RATES (SNDRV_PCM_RATE_8000_96000)
763 
764 #define ATMEL_SSC_FORMATS (SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_S16_LE |\
765 			  SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
766 
767 static const struct snd_soc_dai_ops atmel_ssc_dai_ops = {
768 	.startup	= atmel_ssc_startup,
769 	.shutdown	= atmel_ssc_shutdown,
770 	.prepare	= atmel_ssc_prepare,
771 	.trigger	= atmel_ssc_trigger,
772 	.hw_params	= atmel_ssc_hw_params,
773 	.set_fmt	= atmel_ssc_set_dai_fmt,
774 	.set_clkdiv	= atmel_ssc_set_dai_clkdiv,
775 };
776 
777 static struct snd_soc_dai_driver atmel_ssc_dai = {
778 		.suspend = atmel_ssc_suspend,
779 		.resume = atmel_ssc_resume,
780 		.playback = {
781 			.channels_min = 1,
782 			.channels_max = 2,
783 			.rates = ATMEL_SSC_RATES,
784 			.formats = ATMEL_SSC_FORMATS,},
785 		.capture = {
786 			.channels_min = 1,
787 			.channels_max = 2,
788 			.rates = ATMEL_SSC_RATES,
789 			.formats = ATMEL_SSC_FORMATS,},
790 		.ops = &atmel_ssc_dai_ops,
791 };
792 
793 static const struct snd_soc_component_driver atmel_ssc_component = {
794 	.name		= "atmel-ssc",
795 };
796 
797 static int asoc_ssc_init(struct device *dev)
798 {
799 	struct platform_device *pdev = to_platform_device(dev);
800 	struct ssc_device *ssc = platform_get_drvdata(pdev);
801 	int ret;
802 
803 	ret = snd_soc_register_component(dev, &atmel_ssc_component,
804 					 &atmel_ssc_dai, 1);
805 	if (ret) {
806 		dev_err(dev, "Could not register DAI: %d\n", ret);
807 		goto err;
808 	}
809 
810 	if (ssc->pdata->use_dma)
811 		ret = atmel_pcm_dma_platform_register(dev);
812 	else
813 		ret = atmel_pcm_pdc_platform_register(dev);
814 
815 	if (ret) {
816 		dev_err(dev, "Could not register PCM: %d\n", ret);
817 		goto err_unregister_dai;
818 	}
819 
820 	return 0;
821 
822 err_unregister_dai:
823 	snd_soc_unregister_component(dev);
824 err:
825 	return ret;
826 }
827 
828 static void asoc_ssc_exit(struct device *dev)
829 {
830 	struct platform_device *pdev = to_platform_device(dev);
831 	struct ssc_device *ssc = platform_get_drvdata(pdev);
832 
833 	if (ssc->pdata->use_dma)
834 		atmel_pcm_dma_platform_unregister(dev);
835 	else
836 		atmel_pcm_pdc_platform_unregister(dev);
837 
838 	snd_soc_unregister_component(dev);
839 }
840 
841 /**
842  * atmel_ssc_set_audio - Allocate the specified SSC for audio use.
843  */
844 int atmel_ssc_set_audio(int ssc_id)
845 {
846 	struct ssc_device *ssc;
847 	int ret;
848 
849 	/* If we can grab the SSC briefly to parent the DAI device off it */
850 	ssc = ssc_request(ssc_id);
851 	if (IS_ERR(ssc)) {
852 		pr_err("Unable to parent ASoC SSC DAI on SSC: %ld\n",
853 			PTR_ERR(ssc));
854 		return PTR_ERR(ssc);
855 	} else {
856 		ssc_info[ssc_id].ssc = ssc;
857 	}
858 
859 	ret = asoc_ssc_init(&ssc->pdev->dev);
860 
861 	return ret;
862 }
863 EXPORT_SYMBOL_GPL(atmel_ssc_set_audio);
864 
865 void atmel_ssc_put_audio(int ssc_id)
866 {
867 	struct ssc_device *ssc = ssc_info[ssc_id].ssc;
868 
869 	asoc_ssc_exit(&ssc->pdev->dev);
870 	ssc_free(ssc);
871 }
872 EXPORT_SYMBOL_GPL(atmel_ssc_put_audio);
873 
874 /* Module information */
875 MODULE_AUTHOR("Sedji Gaouaou, sedji.gaouaou@atmel.com, www.atmel.com");
876 MODULE_DESCRIPTION("ATMEL SSC ASoC Interface");
877 MODULE_LICENSE("GPL");
878