xref: /openbmc/linux/sound/soc/atmel/atmel_ssc_dai.c (revision 609e478b)
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_dau: 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->cmr_div == 0)
314 			ssc_p->cmr_div = div;
315 		else
316 			if (div != ssc_p->cmr_div)
317 				return -EBUSY;
318 		break;
319 
320 	case ATMEL_SSC_TCMR_PERIOD:
321 		ssc_p->tcmr_period = div;
322 		break;
323 
324 	case ATMEL_SSC_RCMR_PERIOD:
325 		ssc_p->rcmr_period = div;
326 		break;
327 
328 	default:
329 		return -EINVAL;
330 	}
331 
332 	return 0;
333 }
334 
335 /*
336  * Configure the SSC.
337  */
338 static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
339 	struct snd_pcm_hw_params *params,
340 	struct snd_soc_dai *dai)
341 {
342 	int id = dai->id;
343 	struct atmel_ssc_info *ssc_p = &ssc_info[id];
344 	struct ssc_device *ssc = ssc_p->ssc;
345 	struct atmel_pcm_dma_params *dma_params;
346 	int dir, channels, bits;
347 	u32 tfmr, rfmr, tcmr, rcmr;
348 	int start_event;
349 	int ret;
350 	int fslen, fslen_ext;
351 
352 	/*
353 	 * Currently, there is only one set of dma params for
354 	 * each direction.  If more are added, this code will
355 	 * have to be changed to select the proper set.
356 	 */
357 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
358 		dir = 0;
359 	else
360 		dir = 1;
361 
362 	dma_params = ssc_p->dma_params[dir];
363 
364 	channels = params_channels(params);
365 
366 	/*
367 	 * Determine sample size in bits and the PDC increment.
368 	 */
369 	switch (params_format(params)) {
370 	case SNDRV_PCM_FORMAT_S8:
371 		bits = 8;
372 		dma_params->pdc_xfer_size = 1;
373 		break;
374 	case SNDRV_PCM_FORMAT_S16_LE:
375 		bits = 16;
376 		dma_params->pdc_xfer_size = 2;
377 		break;
378 	case SNDRV_PCM_FORMAT_S24_LE:
379 		bits = 24;
380 		dma_params->pdc_xfer_size = 4;
381 		break;
382 	case SNDRV_PCM_FORMAT_S32_LE:
383 		bits = 32;
384 		dma_params->pdc_xfer_size = 4;
385 		break;
386 	default:
387 		printk(KERN_WARNING "atmel_ssc_dai: unsupported PCM format");
388 		return -EINVAL;
389 	}
390 
391 	/*
392 	 * Compute SSC register settings.
393 	 */
394 	switch (ssc_p->daifmt
395 		& (SND_SOC_DAIFMT_FORMAT_MASK | SND_SOC_DAIFMT_MASTER_MASK)) {
396 
397 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBS_CFS:
398 		/*
399 		 * I2S format, SSC provides BCLK and LRC clocks.
400 		 *
401 		 * The SSC transmit and receive clocks are generated
402 		 * from the MCK divider, and the BCLK signal
403 		 * is output on the SSC TK line.
404 		 */
405 
406 		if (bits > 16 && !ssc->pdata->has_fslen_ext) {
407 			dev_err(dai->dev,
408 				"sample size %d is too large for SSC device\n",
409 				bits);
410 			return -EINVAL;
411 		}
412 
413 		fslen_ext = (bits - 1) / 16;
414 		fslen = (bits - 1) % 16;
415 
416 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
417 			| SSC_BF(RCMR_STTDLY, START_DELAY)
418 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
419 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
420 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
421 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
422 
423 		rfmr =    SSC_BF(RFMR_FSLEN_EXT, fslen_ext)
424 			| SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
425 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NEGATIVE)
426 			| SSC_BF(RFMR_FSLEN, fslen)
427 			| SSC_BF(RFMR_DATNB, (channels - 1))
428 			| SSC_BIT(RFMR_MSBF)
429 			| SSC_BF(RFMR_LOOP, 0)
430 			| SSC_BF(RFMR_DATLEN, (bits - 1));
431 
432 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
433 			| SSC_BF(TCMR_STTDLY, START_DELAY)
434 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
435 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
436 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
437 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
438 
439 		tfmr =    SSC_BF(TFMR_FSLEN_EXT, fslen_ext)
440 			| SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
441 			| SSC_BF(TFMR_FSDEN, 0)
442 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NEGATIVE)
443 			| SSC_BF(TFMR_FSLEN, fslen)
444 			| SSC_BF(TFMR_DATNB, (channels - 1))
445 			| SSC_BIT(TFMR_MSBF)
446 			| SSC_BF(TFMR_DATDEF, 0)
447 			| SSC_BF(TFMR_DATLEN, (bits - 1));
448 		break;
449 
450 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBM_CFM:
451 		/*
452 		 * I2S format, CODEC supplies BCLK and LRC clocks.
453 		 *
454 		 * The SSC transmit clock is obtained from the BCLK signal on
455 		 * on the TK line, and the SSC receive clock is
456 		 * generated from the transmit clock.
457 		 *
458 		 *  For single channel data, one sample is transferred
459 		 * on the falling edge of the LRC clock.
460 		 * For two channel data, one sample is
461 		 * transferred on both edges of the LRC clock.
462 		 */
463 		start_event = ((channels == 1)
464 				? SSC_START_FALLING_RF
465 				: SSC_START_EDGE_RF);
466 
467 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
468 			| SSC_BF(RCMR_STTDLY, START_DELAY)
469 			| SSC_BF(RCMR_START, start_event)
470 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
471 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
472 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
473 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
474 
475 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
476 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
477 			| SSC_BF(RFMR_FSLEN, 0)
478 			| SSC_BF(RFMR_DATNB, 0)
479 			| SSC_BIT(RFMR_MSBF)
480 			| SSC_BF(RFMR_LOOP, 0)
481 			| SSC_BF(RFMR_DATLEN, (bits - 1));
482 
483 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
484 			| SSC_BF(TCMR_STTDLY, START_DELAY)
485 			| SSC_BF(TCMR_START, start_event)
486 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
487 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
488 			| SSC_BF(TCMR_CKS, ssc->clk_from_rk_pin ?
489 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
490 
491 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
492 			| SSC_BF(TFMR_FSDEN, 0)
493 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
494 			| SSC_BF(TFMR_FSLEN, 0)
495 			| SSC_BF(TFMR_DATNB, 0)
496 			| SSC_BIT(TFMR_MSBF)
497 			| SSC_BF(TFMR_DATDEF, 0)
498 			| SSC_BF(TFMR_DATLEN, (bits - 1));
499 		break;
500 
501 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBS_CFS:
502 		/*
503 		 * DSP/PCM Mode A format, SSC provides BCLK and LRC clocks.
504 		 *
505 		 * The SSC transmit and receive clocks are generated from the
506 		 * MCK divider, and the BCLK signal is output
507 		 * on the SSC TK line.
508 		 */
509 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
510 			| SSC_BF(RCMR_STTDLY, 1)
511 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
512 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
513 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
514 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
515 
516 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
517 			| SSC_BF(RFMR_FSOS, SSC_FSOS_POSITIVE)
518 			| SSC_BF(RFMR_FSLEN, 0)
519 			| SSC_BF(RFMR_DATNB, (channels - 1))
520 			| SSC_BIT(RFMR_MSBF)
521 			| SSC_BF(RFMR_LOOP, 0)
522 			| SSC_BF(RFMR_DATLEN, (bits - 1));
523 
524 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
525 			| SSC_BF(TCMR_STTDLY, 1)
526 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
527 			| SSC_BF(TCMR_CKI, SSC_CKI_RISING)
528 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
529 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
530 
531 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
532 			| SSC_BF(TFMR_FSDEN, 0)
533 			| SSC_BF(TFMR_FSOS, SSC_FSOS_POSITIVE)
534 			| SSC_BF(TFMR_FSLEN, 0)
535 			| SSC_BF(TFMR_DATNB, (channels - 1))
536 			| SSC_BIT(TFMR_MSBF)
537 			| SSC_BF(TFMR_DATDEF, 0)
538 			| SSC_BF(TFMR_DATLEN, (bits - 1));
539 		break;
540 
541 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBM_CFM:
542 		/*
543 		 * DSP/PCM Mode A format, CODEC supplies BCLK and LRC clocks.
544 		 *
545 		 * The SSC transmit clock is obtained from the BCLK signal on
546 		 * on the TK line, and the SSC receive clock is
547 		 * generated from the transmit clock.
548 		 *
549 		 * Data is transferred on first BCLK after LRC pulse rising
550 		 * edge.If stereo, the right channel data is contiguous with
551 		 * the left channel data.
552 		 */
553 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
554 			| SSC_BF(RCMR_STTDLY, START_DELAY)
555 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
556 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
557 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
558 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
559 					   SSC_CKS_PIN : SSC_CKS_CLOCK);
560 
561 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
562 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
563 			| SSC_BF(RFMR_FSLEN, 0)
564 			| SSC_BF(RFMR_DATNB, (channels - 1))
565 			| SSC_BIT(RFMR_MSBF)
566 			| SSC_BF(RFMR_LOOP, 0)
567 			| SSC_BF(RFMR_DATLEN, (bits - 1));
568 
569 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
570 			| SSC_BF(TCMR_STTDLY, START_DELAY)
571 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
572 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
573 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
574 			| SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?
575 					   SSC_CKS_CLOCK : SSC_CKS_PIN);
576 
577 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
578 			| SSC_BF(TFMR_FSDEN, 0)
579 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
580 			| SSC_BF(TFMR_FSLEN, 0)
581 			| SSC_BF(TFMR_DATNB, (channels - 1))
582 			| SSC_BIT(TFMR_MSBF)
583 			| SSC_BF(TFMR_DATDEF, 0)
584 			| SSC_BF(TFMR_DATLEN, (bits - 1));
585 		break;
586 
587 	default:
588 		printk(KERN_WARNING "atmel_ssc_dai: unsupported DAI format 0x%x\n",
589 			ssc_p->daifmt);
590 		return -EINVAL;
591 	}
592 	pr_debug("atmel_ssc_hw_params: "
593 			"RCMR=%08x RFMR=%08x TCMR=%08x TFMR=%08x\n",
594 			rcmr, rfmr, tcmr, tfmr);
595 
596 	if (!ssc_p->initialized) {
597 
598 		/* Enable PMC peripheral clock for this SSC */
599 		pr_debug("atmel_ssc_dai: Starting clock\n");
600 		clk_enable(ssc_p->ssc->clk);
601 
602 		/* Reset the SSC and its PDC registers */
603 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
604 
605 		ssc_writel(ssc_p->ssc->regs, PDC_RPR, 0);
606 		ssc_writel(ssc_p->ssc->regs, PDC_RCR, 0);
607 		ssc_writel(ssc_p->ssc->regs, PDC_RNPR, 0);
608 		ssc_writel(ssc_p->ssc->regs, PDC_RNCR, 0);
609 
610 		ssc_writel(ssc_p->ssc->regs, PDC_TPR, 0);
611 		ssc_writel(ssc_p->ssc->regs, PDC_TCR, 0);
612 		ssc_writel(ssc_p->ssc->regs, PDC_TNPR, 0);
613 		ssc_writel(ssc_p->ssc->regs, PDC_TNCR, 0);
614 
615 		ret = request_irq(ssc_p->ssc->irq, atmel_ssc_interrupt, 0,
616 				ssc_p->name, ssc_p);
617 		if (ret < 0) {
618 			printk(KERN_WARNING
619 					"atmel_ssc_dai: request_irq failure\n");
620 			pr_debug("Atmel_ssc_dai: Stoping clock\n");
621 			clk_disable(ssc_p->ssc->clk);
622 			return ret;
623 		}
624 
625 		ssc_p->initialized = 1;
626 	}
627 
628 	/* set SSC clock mode register */
629 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->cmr_div);
630 
631 	/* set receive clock mode and format */
632 	ssc_writel(ssc_p->ssc->regs, RCMR, rcmr);
633 	ssc_writel(ssc_p->ssc->regs, RFMR, rfmr);
634 
635 	/* set transmit clock mode and format */
636 	ssc_writel(ssc_p->ssc->regs, TCMR, tcmr);
637 	ssc_writel(ssc_p->ssc->regs, TFMR, tfmr);
638 
639 	pr_debug("atmel_ssc_dai,hw_params: SSC initialized\n");
640 	return 0;
641 }
642 
643 
644 static int atmel_ssc_prepare(struct snd_pcm_substream *substream,
645 			     struct snd_soc_dai *dai)
646 {
647 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
648 	struct atmel_pcm_dma_params *dma_params;
649 	int dir;
650 
651 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
652 		dir = 0;
653 	else
654 		dir = 1;
655 
656 	dma_params = ssc_p->dma_params[dir];
657 
658 	ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
659 	ssc_writel(ssc_p->ssc->regs, IDR, dma_params->mask->ssc_error);
660 
661 	pr_debug("%s enabled SSC_SR=0x%08x\n",
662 			dir ? "receive" : "transmit",
663 			ssc_readl(ssc_p->ssc->regs, SR));
664 	return 0;
665 }
666 
667 static int atmel_ssc_trigger(struct snd_pcm_substream *substream,
668 			     int cmd, struct snd_soc_dai *dai)
669 {
670 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
671 	struct atmel_pcm_dma_params *dma_params;
672 	int dir;
673 
674 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
675 		dir = 0;
676 	else
677 		dir = 1;
678 
679 	dma_params = ssc_p->dma_params[dir];
680 
681 	switch (cmd) {
682 	case SNDRV_PCM_TRIGGER_START:
683 	case SNDRV_PCM_TRIGGER_RESUME:
684 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
685 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_enable);
686 		break;
687 	default:
688 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
689 		break;
690 	}
691 
692 	return 0;
693 }
694 
695 #ifdef CONFIG_PM
696 static int atmel_ssc_suspend(struct snd_soc_dai *cpu_dai)
697 {
698 	struct atmel_ssc_info *ssc_p;
699 
700 	if (!cpu_dai->active)
701 		return 0;
702 
703 	ssc_p = &ssc_info[cpu_dai->id];
704 
705 	/* Save the status register before disabling transmit and receive */
706 	ssc_p->ssc_state.ssc_sr = ssc_readl(ssc_p->ssc->regs, SR);
707 	ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_TXDIS) | SSC_BIT(CR_RXDIS));
708 
709 	/* Save the current interrupt mask, then disable unmasked interrupts */
710 	ssc_p->ssc_state.ssc_imr = ssc_readl(ssc_p->ssc->regs, IMR);
711 	ssc_writel(ssc_p->ssc->regs, IDR, ssc_p->ssc_state.ssc_imr);
712 
713 	ssc_p->ssc_state.ssc_cmr = ssc_readl(ssc_p->ssc->regs, CMR);
714 	ssc_p->ssc_state.ssc_rcmr = ssc_readl(ssc_p->ssc->regs, RCMR);
715 	ssc_p->ssc_state.ssc_rfmr = ssc_readl(ssc_p->ssc->regs, RFMR);
716 	ssc_p->ssc_state.ssc_tcmr = ssc_readl(ssc_p->ssc->regs, TCMR);
717 	ssc_p->ssc_state.ssc_tfmr = ssc_readl(ssc_p->ssc->regs, TFMR);
718 
719 	return 0;
720 }
721 
722 
723 
724 static int atmel_ssc_resume(struct snd_soc_dai *cpu_dai)
725 {
726 	struct atmel_ssc_info *ssc_p;
727 	u32 cr;
728 
729 	if (!cpu_dai->active)
730 		return 0;
731 
732 	ssc_p = &ssc_info[cpu_dai->id];
733 
734 	/* restore SSC register settings */
735 	ssc_writel(ssc_p->ssc->regs, TFMR, ssc_p->ssc_state.ssc_tfmr);
736 	ssc_writel(ssc_p->ssc->regs, TCMR, ssc_p->ssc_state.ssc_tcmr);
737 	ssc_writel(ssc_p->ssc->regs, RFMR, ssc_p->ssc_state.ssc_rfmr);
738 	ssc_writel(ssc_p->ssc->regs, RCMR, ssc_p->ssc_state.ssc_rcmr);
739 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->ssc_state.ssc_cmr);
740 
741 	/* re-enable interrupts */
742 	ssc_writel(ssc_p->ssc->regs, IER, ssc_p->ssc_state.ssc_imr);
743 
744 	/* Re-enable receive and transmit as appropriate */
745 	cr = 0;
746 	cr |=
747 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_RXEN)) ? SSC_BIT(CR_RXEN) : 0;
748 	cr |=
749 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_TXEN)) ? SSC_BIT(CR_TXEN) : 0;
750 	ssc_writel(ssc_p->ssc->regs, CR, cr);
751 
752 	return 0;
753 }
754 #else /* CONFIG_PM */
755 #  define atmel_ssc_suspend	NULL
756 #  define atmel_ssc_resume	NULL
757 #endif /* CONFIG_PM */
758 
759 #define ATMEL_SSC_RATES (SNDRV_PCM_RATE_8000_96000)
760 
761 #define ATMEL_SSC_FORMATS (SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_S16_LE |\
762 			  SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
763 
764 static const struct snd_soc_dai_ops atmel_ssc_dai_ops = {
765 	.startup	= atmel_ssc_startup,
766 	.shutdown	= atmel_ssc_shutdown,
767 	.prepare	= atmel_ssc_prepare,
768 	.trigger	= atmel_ssc_trigger,
769 	.hw_params	= atmel_ssc_hw_params,
770 	.set_fmt	= atmel_ssc_set_dai_fmt,
771 	.set_clkdiv	= atmel_ssc_set_dai_clkdiv,
772 };
773 
774 static struct snd_soc_dai_driver atmel_ssc_dai = {
775 		.suspend = atmel_ssc_suspend,
776 		.resume = atmel_ssc_resume,
777 		.playback = {
778 			.channels_min = 1,
779 			.channels_max = 2,
780 			.rates = ATMEL_SSC_RATES,
781 			.formats = ATMEL_SSC_FORMATS,},
782 		.capture = {
783 			.channels_min = 1,
784 			.channels_max = 2,
785 			.rates = ATMEL_SSC_RATES,
786 			.formats = ATMEL_SSC_FORMATS,},
787 		.ops = &atmel_ssc_dai_ops,
788 };
789 
790 static const struct snd_soc_component_driver atmel_ssc_component = {
791 	.name		= "atmel-ssc",
792 };
793 
794 static int asoc_ssc_init(struct device *dev)
795 {
796 	struct platform_device *pdev = to_platform_device(dev);
797 	struct ssc_device *ssc = platform_get_drvdata(pdev);
798 	int ret;
799 
800 	ret = snd_soc_register_component(dev, &atmel_ssc_component,
801 					 &atmel_ssc_dai, 1);
802 	if (ret) {
803 		dev_err(dev, "Could not register DAI: %d\n", ret);
804 		goto err;
805 	}
806 
807 	if (ssc->pdata->use_dma)
808 		ret = atmel_pcm_dma_platform_register(dev);
809 	else
810 		ret = atmel_pcm_pdc_platform_register(dev);
811 
812 	if (ret) {
813 		dev_err(dev, "Could not register PCM: %d\n", ret);
814 		goto err_unregister_dai;
815 	}
816 
817 	return 0;
818 
819 err_unregister_dai:
820 	snd_soc_unregister_component(dev);
821 err:
822 	return ret;
823 }
824 
825 static void asoc_ssc_exit(struct device *dev)
826 {
827 	struct platform_device *pdev = to_platform_device(dev);
828 	struct ssc_device *ssc = platform_get_drvdata(pdev);
829 
830 	if (ssc->pdata->use_dma)
831 		atmel_pcm_dma_platform_unregister(dev);
832 	else
833 		atmel_pcm_pdc_platform_unregister(dev);
834 
835 	snd_soc_unregister_component(dev);
836 }
837 
838 /**
839  * atmel_ssc_set_audio - Allocate the specified SSC for audio use.
840  */
841 int atmel_ssc_set_audio(int ssc_id)
842 {
843 	struct ssc_device *ssc;
844 	int ret;
845 
846 	/* If we can grab the SSC briefly to parent the DAI device off it */
847 	ssc = ssc_request(ssc_id);
848 	if (IS_ERR(ssc)) {
849 		pr_err("Unable to parent ASoC SSC DAI on SSC: %ld\n",
850 			PTR_ERR(ssc));
851 		return PTR_ERR(ssc);
852 	} else {
853 		ssc_info[ssc_id].ssc = ssc;
854 	}
855 
856 	ret = asoc_ssc_init(&ssc->pdev->dev);
857 
858 	return ret;
859 }
860 EXPORT_SYMBOL_GPL(atmel_ssc_set_audio);
861 
862 void atmel_ssc_put_audio(int ssc_id)
863 {
864 	struct ssc_device *ssc = ssc_info[ssc_id].ssc;
865 
866 	asoc_ssc_exit(&ssc->pdev->dev);
867 	ssc_free(ssc);
868 }
869 EXPORT_SYMBOL_GPL(atmel_ssc_put_audio);
870 
871 /* Module information */
872 MODULE_AUTHOR("Sedji Gaouaou, sedji.gaouaou@atmel.com, www.atmel.com");
873 MODULE_DESCRIPTION("ATMEL SSC ASoC Interface");
874 MODULE_LICENSE("GPL");
875