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 <mach/hardware.h>
46 
47 #include "atmel-pcm.h"
48 #include "atmel_ssc_dai.h"
49 
50 
51 #if defined(CONFIG_ARCH_AT91SAM9260) || defined(CONFIG_ARCH_AT91SAM9G20)
52 #define NUM_SSC_DEVICES		1
53 #else
54 #define NUM_SSC_DEVICES		3
55 #endif
56 
57 /*
58  * SSC PDC registers required by the PCM DMA engine.
59  */
60 static struct atmel_pdc_regs pdc_tx_reg = {
61 	.xpr		= ATMEL_PDC_TPR,
62 	.xcr		= ATMEL_PDC_TCR,
63 	.xnpr		= ATMEL_PDC_TNPR,
64 	.xncr		= ATMEL_PDC_TNCR,
65 };
66 
67 static struct atmel_pdc_regs pdc_rx_reg = {
68 	.xpr		= ATMEL_PDC_RPR,
69 	.xcr		= ATMEL_PDC_RCR,
70 	.xnpr		= ATMEL_PDC_RNPR,
71 	.xncr		= ATMEL_PDC_RNCR,
72 };
73 
74 /*
75  * SSC & PDC status bits for transmit and receive.
76  */
77 static struct atmel_ssc_mask ssc_tx_mask = {
78 	.ssc_enable	= SSC_BIT(CR_TXEN),
79 	.ssc_disable	= SSC_BIT(CR_TXDIS),
80 	.ssc_endx	= SSC_BIT(SR_ENDTX),
81 	.ssc_endbuf	= SSC_BIT(SR_TXBUFE),
82 	.pdc_enable	= ATMEL_PDC_TXTEN,
83 	.pdc_disable	= ATMEL_PDC_TXTDIS,
84 };
85 
86 static struct atmel_ssc_mask ssc_rx_mask = {
87 	.ssc_enable	= SSC_BIT(CR_RXEN),
88 	.ssc_disable	= SSC_BIT(CR_RXDIS),
89 	.ssc_endx	= SSC_BIT(SR_ENDRX),
90 	.ssc_endbuf	= SSC_BIT(SR_RXBUFF),
91 	.pdc_enable	= ATMEL_PDC_RXTEN,
92 	.pdc_disable	= ATMEL_PDC_RXTDIS,
93 };
94 
95 
96 /*
97  * DMA parameters.
98  */
99 static struct atmel_pcm_dma_params ssc_dma_params[NUM_SSC_DEVICES][2] = {
100 	{{
101 	.name		= "SSC0 PCM out",
102 	.pdc		= &pdc_tx_reg,
103 	.mask		= &ssc_tx_mask,
104 	},
105 	{
106 	.name		= "SSC0 PCM in",
107 	.pdc		= &pdc_rx_reg,
108 	.mask		= &ssc_rx_mask,
109 	} },
110 #if NUM_SSC_DEVICES == 3
111 	{{
112 	.name		= "SSC1 PCM out",
113 	.pdc		= &pdc_tx_reg,
114 	.mask		= &ssc_tx_mask,
115 	},
116 	{
117 	.name		= "SSC1 PCM in",
118 	.pdc		= &pdc_rx_reg,
119 	.mask		= &ssc_rx_mask,
120 	} },
121 	{{
122 	.name		= "SSC2 PCM out",
123 	.pdc		= &pdc_tx_reg,
124 	.mask		= &ssc_tx_mask,
125 	},
126 	{
127 	.name		= "SSC2 PCM in",
128 	.pdc		= &pdc_rx_reg,
129 	.mask		= &ssc_rx_mask,
130 	} },
131 #endif
132 };
133 
134 
135 static struct atmel_ssc_info ssc_info[NUM_SSC_DEVICES] = {
136 	{
137 	.name		= "ssc0",
138 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[0].lock),
139 	.dir_mask	= SSC_DIR_MASK_UNUSED,
140 	.initialized	= 0,
141 	},
142 #if NUM_SSC_DEVICES == 3
143 	{
144 	.name		= "ssc1",
145 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[1].lock),
146 	.dir_mask	= SSC_DIR_MASK_UNUSED,
147 	.initialized	= 0,
148 	},
149 	{
150 	.name		= "ssc2",
151 	.lock		= __SPIN_LOCK_UNLOCKED(ssc_info[2].lock),
152 	.dir_mask	= SSC_DIR_MASK_UNUSED,
153 	.initialized	= 0,
154 	},
155 #endif
156 };
157 
158 
159 /*
160  * SSC interrupt handler.  Passes PDC interrupts to the DMA
161  * interrupt handler in the PCM driver.
162  */
atmel_ssc_interrupt(int irq,void * dev_id)163 static irqreturn_t atmel_ssc_interrupt(int irq, void *dev_id)
164 {
165 	struct atmel_ssc_info *ssc_p = dev_id;
166 	struct atmel_pcm_dma_params *dma_params;
167 	u32 ssc_sr;
168 	u32 ssc_substream_mask;
169 	int i;
170 
171 	ssc_sr = (unsigned long)ssc_readl(ssc_p->ssc->regs, SR)
172 			& (unsigned long)ssc_readl(ssc_p->ssc->regs, IMR);
173 
174 	/*
175 	 * Loop through the substreams attached to this SSC.  If
176 	 * a DMA-related interrupt occurred on that substream, call
177 	 * the DMA interrupt handler function, if one has been
178 	 * registered in the dma_params structure by the PCM driver.
179 	 */
180 	for (i = 0; i < ARRAY_SIZE(ssc_p->dma_params); i++) {
181 		dma_params = ssc_p->dma_params[i];
182 
183 		if ((dma_params != NULL) &&
184 			(dma_params->dma_intr_handler != NULL)) {
185 			ssc_substream_mask = (dma_params->mask->ssc_endx |
186 					dma_params->mask->ssc_endbuf);
187 			if (ssc_sr & ssc_substream_mask) {
188 				dma_params->dma_intr_handler(ssc_sr,
189 						dma_params->
190 						substream);
191 			}
192 		}
193 	}
194 
195 	return IRQ_HANDLED;
196 }
197 
198 
199 /*-------------------------------------------------------------------------*\
200  * DAI functions
201 \*-------------------------------------------------------------------------*/
202 /*
203  * Startup.  Only that one substream allowed in each direction.
204  */
atmel_ssc_startup(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)205 static int atmel_ssc_startup(struct snd_pcm_substream *substream,
206 			     struct snd_soc_dai *dai)
207 {
208 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
209 	int dir_mask;
210 
211 	pr_debug("atmel_ssc_startup: SSC_SR=0x%u\n",
212 		ssc_readl(ssc_p->ssc->regs, SR));
213 
214 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
215 		dir_mask = SSC_DIR_MASK_PLAYBACK;
216 	else
217 		dir_mask = SSC_DIR_MASK_CAPTURE;
218 
219 	spin_lock_irq(&ssc_p->lock);
220 	if (ssc_p->dir_mask & dir_mask) {
221 		spin_unlock_irq(&ssc_p->lock);
222 		return -EBUSY;
223 	}
224 	ssc_p->dir_mask |= dir_mask;
225 	spin_unlock_irq(&ssc_p->lock);
226 
227 	return 0;
228 }
229 
230 /*
231  * Shutdown.  Clear DMA parameters and shutdown the SSC if there
232  * are no other substreams open.
233  */
atmel_ssc_shutdown(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)234 static void atmel_ssc_shutdown(struct snd_pcm_substream *substream,
235 			       struct snd_soc_dai *dai)
236 {
237 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
238 	struct atmel_pcm_dma_params *dma_params;
239 	int dir, dir_mask;
240 
241 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
242 		dir = 0;
243 	else
244 		dir = 1;
245 
246 	dma_params = ssc_p->dma_params[dir];
247 
248 	if (dma_params != NULL) {
249 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
250 		pr_debug("atmel_ssc_shutdown: %s disabled SSC_SR=0x%08x\n",
251 			(dir ? "receive" : "transmit"),
252 			ssc_readl(ssc_p->ssc->regs, SR));
253 
254 		dma_params->ssc = NULL;
255 		dma_params->substream = NULL;
256 		ssc_p->dma_params[dir] = NULL;
257 	}
258 
259 	dir_mask = 1 << dir;
260 
261 	spin_lock_irq(&ssc_p->lock);
262 	ssc_p->dir_mask &= ~dir_mask;
263 	if (!ssc_p->dir_mask) {
264 		if (ssc_p->initialized) {
265 			/* Shutdown the SSC clock. */
266 			pr_debug("atmel_ssc_dau: Stopping clock\n");
267 			clk_disable(ssc_p->ssc->clk);
268 
269 			free_irq(ssc_p->ssc->irq, ssc_p);
270 			ssc_p->initialized = 0;
271 		}
272 
273 		/* Reset the SSC */
274 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
275 		/* Clear the SSC dividers */
276 		ssc_p->cmr_div = ssc_p->tcmr_period = ssc_p->rcmr_period = 0;
277 	}
278 	spin_unlock_irq(&ssc_p->lock);
279 }
280 
281 
282 /*
283  * Record the DAI format for use in hw_params().
284  */
atmel_ssc_set_dai_fmt(struct snd_soc_dai * cpu_dai,unsigned int fmt)285 static int atmel_ssc_set_dai_fmt(struct snd_soc_dai *cpu_dai,
286 		unsigned int fmt)
287 {
288 	struct atmel_ssc_info *ssc_p = &ssc_info[cpu_dai->id];
289 
290 	ssc_p->daifmt = fmt;
291 	return 0;
292 }
293 
294 /*
295  * Record SSC clock dividers for use in hw_params().
296  */
atmel_ssc_set_dai_clkdiv(struct snd_soc_dai * cpu_dai,int div_id,int div)297 static int atmel_ssc_set_dai_clkdiv(struct snd_soc_dai *cpu_dai,
298 	int div_id, int div)
299 {
300 	struct atmel_ssc_info *ssc_p = &ssc_info[cpu_dai->id];
301 
302 	switch (div_id) {
303 	case ATMEL_SSC_CMR_DIV:
304 		/*
305 		 * The same master clock divider is used for both
306 		 * transmit and receive, so if a value has already
307 		 * been set, it must match this value.
308 		 */
309 		if (ssc_p->cmr_div == 0)
310 			ssc_p->cmr_div = div;
311 		else
312 			if (div != ssc_p->cmr_div)
313 				return -EBUSY;
314 		break;
315 
316 	case ATMEL_SSC_TCMR_PERIOD:
317 		ssc_p->tcmr_period = div;
318 		break;
319 
320 	case ATMEL_SSC_RCMR_PERIOD:
321 		ssc_p->rcmr_period = div;
322 		break;
323 
324 	default:
325 		return -EINVAL;
326 	}
327 
328 	return 0;
329 }
330 
331 /*
332  * Configure the SSC.
333  */
atmel_ssc_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * dai)334 static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
335 	struct snd_pcm_hw_params *params,
336 	struct snd_soc_dai *dai)
337 {
338 	struct snd_soc_pcm_runtime *rtd = snd_pcm_substream_chip(substream);
339 	int id = dai->id;
340 	struct atmel_ssc_info *ssc_p = &ssc_info[id];
341 	struct atmel_pcm_dma_params *dma_params;
342 	int dir, channels, bits;
343 	u32 tfmr, rfmr, tcmr, rcmr;
344 	int start_event;
345 	int ret;
346 
347 	/*
348 	 * Currently, there is only one set of dma params for
349 	 * each direction.  If more are added, this code will
350 	 * have to be changed to select the proper set.
351 	 */
352 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
353 		dir = 0;
354 	else
355 		dir = 1;
356 
357 	dma_params = &ssc_dma_params[id][dir];
358 	dma_params->ssc = ssc_p->ssc;
359 	dma_params->substream = substream;
360 
361 	ssc_p->dma_params[dir] = dma_params;
362 
363 	/*
364 	 * The snd_soc_pcm_stream->dma_data field is only used to communicate
365 	 * the appropriate DMA parameters to the pcm driver hw_params()
366 	 * function.  It should not be used for other purposes
367 	 * as it is common to all substreams.
368 	 */
369 	snd_soc_dai_set_dma_data(rtd->cpu_dai, substream, dma_params);
370 
371 	channels = params_channels(params);
372 
373 	/*
374 	 * Determine sample size in bits and the PDC increment.
375 	 */
376 	switch (params_format(params)) {
377 	case SNDRV_PCM_FORMAT_S8:
378 		bits = 8;
379 		dma_params->pdc_xfer_size = 1;
380 		break;
381 	case SNDRV_PCM_FORMAT_S16_LE:
382 		bits = 16;
383 		dma_params->pdc_xfer_size = 2;
384 		break;
385 	case SNDRV_PCM_FORMAT_S24_LE:
386 		bits = 24;
387 		dma_params->pdc_xfer_size = 4;
388 		break;
389 	case SNDRV_PCM_FORMAT_S32_LE:
390 		bits = 32;
391 		dma_params->pdc_xfer_size = 4;
392 		break;
393 	default:
394 		printk(KERN_WARNING "atmel_ssc_dai: unsupported PCM format");
395 		return -EINVAL;
396 	}
397 
398 	/*
399 	 * The SSC only supports up to 16-bit samples in I2S format, due
400 	 * to the size of the Frame Mode Register FSLEN field.
401 	 */
402 	if ((ssc_p->daifmt & SND_SOC_DAIFMT_FORMAT_MASK) == SND_SOC_DAIFMT_I2S
403 		&& bits > 16) {
404 		printk(KERN_WARNING
405 				"atmel_ssc_dai: sample size %d "
406 				"is too large for I2S\n", bits);
407 		return -EINVAL;
408 	}
409 
410 	/*
411 	 * Compute SSC register settings.
412 	 */
413 	switch (ssc_p->daifmt
414 		& (SND_SOC_DAIFMT_FORMAT_MASK | SND_SOC_DAIFMT_MASTER_MASK)) {
415 
416 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBS_CFS:
417 		/*
418 		 * I2S format, SSC provides BCLK and LRC clocks.
419 		 *
420 		 * The SSC transmit and receive clocks are generated
421 		 * from the MCK divider, and the BCLK signal
422 		 * is output on the SSC TK line.
423 		 */
424 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
425 			| SSC_BF(RCMR_STTDLY, START_DELAY)
426 			| SSC_BF(RCMR_START, SSC_START_FALLING_RF)
427 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
428 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
429 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
430 
431 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
432 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NEGATIVE)
433 			| SSC_BF(RFMR_FSLEN, (bits - 1))
434 			| SSC_BF(RFMR_DATNB, (channels - 1))
435 			| SSC_BIT(RFMR_MSBF)
436 			| SSC_BF(RFMR_LOOP, 0)
437 			| SSC_BF(RFMR_DATLEN, (bits - 1));
438 
439 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
440 			| SSC_BF(TCMR_STTDLY, START_DELAY)
441 			| SSC_BF(TCMR_START, SSC_START_FALLING_RF)
442 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
443 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
444 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
445 
446 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
447 			| SSC_BF(TFMR_FSDEN, 0)
448 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NEGATIVE)
449 			| SSC_BF(TFMR_FSLEN, (bits - 1))
450 			| SSC_BF(TFMR_DATNB, (channels - 1))
451 			| SSC_BIT(TFMR_MSBF)
452 			| SSC_BF(TFMR_DATDEF, 0)
453 			| SSC_BF(TFMR_DATLEN, (bits - 1));
454 		break;
455 
456 	case SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBM_CFM:
457 		/*
458 		 * I2S format, CODEC supplies BCLK and LRC clocks.
459 		 *
460 		 * The SSC transmit clock is obtained from the BCLK signal on
461 		 * on the TK line, and the SSC receive clock is
462 		 * generated from the transmit clock.
463 		 *
464 		 *  For single channel data, one sample is transferred
465 		 * on the falling edge of the LRC clock.
466 		 * For two channel data, one sample is
467 		 * transferred on both edges of the LRC clock.
468 		 */
469 		start_event = ((channels == 1)
470 				? SSC_START_FALLING_RF
471 				: SSC_START_EDGE_RF);
472 
473 		rcmr =	  SSC_BF(RCMR_PERIOD, 0)
474 			| SSC_BF(RCMR_STTDLY, START_DELAY)
475 			| SSC_BF(RCMR_START, start_event)
476 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
477 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
478 			| SSC_BF(RCMR_CKS, SSC_CKS_CLOCK);
479 
480 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
481 			| SSC_BF(RFMR_FSOS, SSC_FSOS_NONE)
482 			| SSC_BF(RFMR_FSLEN, 0)
483 			| SSC_BF(RFMR_DATNB, 0)
484 			| SSC_BIT(RFMR_MSBF)
485 			| SSC_BF(RFMR_LOOP, 0)
486 			| SSC_BF(RFMR_DATLEN, (bits - 1));
487 
488 		tcmr =	  SSC_BF(TCMR_PERIOD, 0)
489 			| SSC_BF(TCMR_STTDLY, START_DELAY)
490 			| SSC_BF(TCMR_START, start_event)
491 			| SSC_BF(TCMR_CKI, SSC_CKI_FALLING)
492 			| SSC_BF(TCMR_CKO, SSC_CKO_NONE)
493 			| SSC_BF(TCMR_CKS, SSC_CKS_PIN);
494 
495 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
496 			| SSC_BF(TFMR_FSDEN, 0)
497 			| SSC_BF(TFMR_FSOS, SSC_FSOS_NONE)
498 			| SSC_BF(TFMR_FSLEN, 0)
499 			| SSC_BF(TFMR_DATNB, 0)
500 			| SSC_BIT(TFMR_MSBF)
501 			| SSC_BF(TFMR_DATDEF, 0)
502 			| SSC_BF(TFMR_DATLEN, (bits - 1));
503 		break;
504 
505 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBS_CFS:
506 		/*
507 		 * DSP/PCM Mode A format, SSC provides BCLK and LRC clocks.
508 		 *
509 		 * The SSC transmit and receive clocks are generated from the
510 		 * MCK divider, and the BCLK signal is output
511 		 * on the SSC TK line.
512 		 */
513 		rcmr =	  SSC_BF(RCMR_PERIOD, ssc_p->rcmr_period)
514 			| SSC_BF(RCMR_STTDLY, 1)
515 			| SSC_BF(RCMR_START, SSC_START_RISING_RF)
516 			| SSC_BF(RCMR_CKI, SSC_CKI_RISING)
517 			| SSC_BF(RCMR_CKO, SSC_CKO_NONE)
518 			| SSC_BF(RCMR_CKS, SSC_CKS_DIV);
519 
520 		rfmr =	  SSC_BF(RFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
521 			| SSC_BF(RFMR_FSOS, SSC_FSOS_POSITIVE)
522 			| SSC_BF(RFMR_FSLEN, 0)
523 			| SSC_BF(RFMR_DATNB, (channels - 1))
524 			| SSC_BIT(RFMR_MSBF)
525 			| SSC_BF(RFMR_LOOP, 0)
526 			| SSC_BF(RFMR_DATLEN, (bits - 1));
527 
528 		tcmr =	  SSC_BF(TCMR_PERIOD, ssc_p->tcmr_period)
529 			| SSC_BF(TCMR_STTDLY, 1)
530 			| SSC_BF(TCMR_START, SSC_START_RISING_RF)
531 			| SSC_BF(TCMR_CKI, SSC_CKI_RISING)
532 			| SSC_BF(TCMR_CKO, SSC_CKO_CONTINUOUS)
533 			| SSC_BF(TCMR_CKS, SSC_CKS_DIV);
534 
535 		tfmr =	  SSC_BF(TFMR_FSEDGE, SSC_FSEDGE_POSITIVE)
536 			| SSC_BF(TFMR_FSDEN, 0)
537 			| SSC_BF(TFMR_FSOS, SSC_FSOS_POSITIVE)
538 			| SSC_BF(TFMR_FSLEN, 0)
539 			| SSC_BF(TFMR_DATNB, (channels - 1))
540 			| SSC_BIT(TFMR_MSBF)
541 			| SSC_BF(TFMR_DATDEF, 0)
542 			| SSC_BF(TFMR_DATLEN, (bits - 1));
543 		break;
544 
545 	case SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_CBM_CFM:
546 	default:
547 		printk(KERN_WARNING "atmel_ssc_dai: unsupported DAI format 0x%x\n",
548 			ssc_p->daifmt);
549 		return -EINVAL;
550 	}
551 	pr_debug("atmel_ssc_hw_params: "
552 			"RCMR=%08x RFMR=%08x TCMR=%08x TFMR=%08x\n",
553 			rcmr, rfmr, tcmr, tfmr);
554 
555 	if (!ssc_p->initialized) {
556 
557 		/* Enable PMC peripheral clock for this SSC */
558 		pr_debug("atmel_ssc_dai: Starting clock\n");
559 		clk_enable(ssc_p->ssc->clk);
560 
561 		/* Reset the SSC and its PDC registers */
562 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
563 
564 		ssc_writel(ssc_p->ssc->regs, PDC_RPR, 0);
565 		ssc_writel(ssc_p->ssc->regs, PDC_RCR, 0);
566 		ssc_writel(ssc_p->ssc->regs, PDC_RNPR, 0);
567 		ssc_writel(ssc_p->ssc->regs, PDC_RNCR, 0);
568 
569 		ssc_writel(ssc_p->ssc->regs, PDC_TPR, 0);
570 		ssc_writel(ssc_p->ssc->regs, PDC_TCR, 0);
571 		ssc_writel(ssc_p->ssc->regs, PDC_TNPR, 0);
572 		ssc_writel(ssc_p->ssc->regs, PDC_TNCR, 0);
573 
574 		ret = request_irq(ssc_p->ssc->irq, atmel_ssc_interrupt, 0,
575 				ssc_p->name, ssc_p);
576 		if (ret < 0) {
577 			printk(KERN_WARNING
578 					"atmel_ssc_dai: request_irq failure\n");
579 			pr_debug("Atmel_ssc_dai: Stoping clock\n");
580 			clk_disable(ssc_p->ssc->clk);
581 			return ret;
582 		}
583 
584 		ssc_p->initialized = 1;
585 	}
586 
587 	/* set SSC clock mode register */
588 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->cmr_div);
589 
590 	/* set receive clock mode and format */
591 	ssc_writel(ssc_p->ssc->regs, RCMR, rcmr);
592 	ssc_writel(ssc_p->ssc->regs, RFMR, rfmr);
593 
594 	/* set transmit clock mode and format */
595 	ssc_writel(ssc_p->ssc->regs, TCMR, tcmr);
596 	ssc_writel(ssc_p->ssc->regs, TFMR, tfmr);
597 
598 	pr_debug("atmel_ssc_dai,hw_params: SSC initialized\n");
599 	return 0;
600 }
601 
602 
atmel_ssc_prepare(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)603 static int atmel_ssc_prepare(struct snd_pcm_substream *substream,
604 			     struct snd_soc_dai *dai)
605 {
606 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
607 	struct atmel_pcm_dma_params *dma_params;
608 	int dir;
609 
610 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
611 		dir = 0;
612 	else
613 		dir = 1;
614 
615 	dma_params = ssc_p->dma_params[dir];
616 
617 	ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_enable);
618 
619 	pr_debug("%s enabled SSC_SR=0x%08x\n",
620 			dir ? "receive" : "transmit",
621 			ssc_readl(ssc_p->ssc->regs, SR));
622 	return 0;
623 }
624 
625 
626 #ifdef CONFIG_PM
atmel_ssc_suspend(struct snd_soc_dai * cpu_dai)627 static int atmel_ssc_suspend(struct snd_soc_dai *cpu_dai)
628 {
629 	struct atmel_ssc_info *ssc_p;
630 
631 	if (!cpu_dai->active)
632 		return 0;
633 
634 	ssc_p = &ssc_info[cpu_dai->id];
635 
636 	/* Save the status register before disabling transmit and receive */
637 	ssc_p->ssc_state.ssc_sr = ssc_readl(ssc_p->ssc->regs, SR);
638 	ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_TXDIS) | SSC_BIT(CR_RXDIS));
639 
640 	/* Save the current interrupt mask, then disable unmasked interrupts */
641 	ssc_p->ssc_state.ssc_imr = ssc_readl(ssc_p->ssc->regs, IMR);
642 	ssc_writel(ssc_p->ssc->regs, IDR, ssc_p->ssc_state.ssc_imr);
643 
644 	ssc_p->ssc_state.ssc_cmr = ssc_readl(ssc_p->ssc->regs, CMR);
645 	ssc_p->ssc_state.ssc_rcmr = ssc_readl(ssc_p->ssc->regs, RCMR);
646 	ssc_p->ssc_state.ssc_rfmr = ssc_readl(ssc_p->ssc->regs, RFMR);
647 	ssc_p->ssc_state.ssc_tcmr = ssc_readl(ssc_p->ssc->regs, TCMR);
648 	ssc_p->ssc_state.ssc_tfmr = ssc_readl(ssc_p->ssc->regs, TFMR);
649 
650 	return 0;
651 }
652 
653 
654 
atmel_ssc_resume(struct snd_soc_dai * cpu_dai)655 static int atmel_ssc_resume(struct snd_soc_dai *cpu_dai)
656 {
657 	struct atmel_ssc_info *ssc_p;
658 	u32 cr;
659 
660 	if (!cpu_dai->active)
661 		return 0;
662 
663 	ssc_p = &ssc_info[cpu_dai->id];
664 
665 	/* restore SSC register settings */
666 	ssc_writel(ssc_p->ssc->regs, TFMR, ssc_p->ssc_state.ssc_tfmr);
667 	ssc_writel(ssc_p->ssc->regs, TCMR, ssc_p->ssc_state.ssc_tcmr);
668 	ssc_writel(ssc_p->ssc->regs, RFMR, ssc_p->ssc_state.ssc_rfmr);
669 	ssc_writel(ssc_p->ssc->regs, RCMR, ssc_p->ssc_state.ssc_rcmr);
670 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->ssc_state.ssc_cmr);
671 
672 	/* re-enable interrupts */
673 	ssc_writel(ssc_p->ssc->regs, IER, ssc_p->ssc_state.ssc_imr);
674 
675 	/* Re-enable receive and transmit as appropriate */
676 	cr = 0;
677 	cr |=
678 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_RXEN)) ? SSC_BIT(CR_RXEN) : 0;
679 	cr |=
680 	    (ssc_p->ssc_state.ssc_sr & SSC_BIT(SR_TXEN)) ? SSC_BIT(CR_TXEN) : 0;
681 	ssc_writel(ssc_p->ssc->regs, CR, cr);
682 
683 	return 0;
684 }
685 #else /* CONFIG_PM */
686 #  define atmel_ssc_suspend	NULL
687 #  define atmel_ssc_resume	NULL
688 #endif /* CONFIG_PM */
689 
atmel_ssc_probe(struct snd_soc_dai * dai)690 static int atmel_ssc_probe(struct snd_soc_dai *dai)
691 {
692 	struct atmel_ssc_info *ssc_p = &ssc_info[dai->id];
693 	int ret = 0;
694 
695 	snd_soc_dai_set_drvdata(dai, ssc_p);
696 
697 	/*
698 	 * Request SSC device
699 	 */
700 	ssc_p->ssc = ssc_request(dai->id);
701 	if (IS_ERR(ssc_p->ssc)) {
702 		printk(KERN_ERR "ASoC: Failed to request SSC %d\n", dai->id);
703 		ret = PTR_ERR(ssc_p->ssc);
704 	}
705 
706 	return ret;
707 }
708 
atmel_ssc_remove(struct snd_soc_dai * dai)709 static int atmel_ssc_remove(struct snd_soc_dai *dai)
710 {
711 	struct atmel_ssc_info *ssc_p = snd_soc_dai_get_drvdata(dai);
712 
713 	ssc_free(ssc_p->ssc);
714 	return 0;
715 }
716 
717 #define ATMEL_SSC_RATES (SNDRV_PCM_RATE_8000_96000)
718 
719 #define ATMEL_SSC_FORMATS (SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_S16_LE |\
720 			  SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
721 
722 static const struct snd_soc_dai_ops atmel_ssc_dai_ops = {
723 	.startup	= atmel_ssc_startup,
724 	.shutdown	= atmel_ssc_shutdown,
725 	.prepare	= atmel_ssc_prepare,
726 	.hw_params	= atmel_ssc_hw_params,
727 	.set_fmt	= atmel_ssc_set_dai_fmt,
728 	.set_clkdiv	= atmel_ssc_set_dai_clkdiv,
729 };
730 
731 static struct snd_soc_dai_driver atmel_ssc_dai[NUM_SSC_DEVICES] = {
732 	{
733 		.name = "atmel-ssc-dai.0",
734 		.probe = atmel_ssc_probe,
735 		.remove = atmel_ssc_remove,
736 		.suspend = atmel_ssc_suspend,
737 		.resume = atmel_ssc_resume,
738 		.playback = {
739 			.channels_min = 1,
740 			.channels_max = 2,
741 			.rates = ATMEL_SSC_RATES,
742 			.formats = ATMEL_SSC_FORMATS,},
743 		.capture = {
744 			.channels_min = 1,
745 			.channels_max = 2,
746 			.rates = ATMEL_SSC_RATES,
747 			.formats = ATMEL_SSC_FORMATS,},
748 		.ops = &atmel_ssc_dai_ops,
749 	},
750 #if NUM_SSC_DEVICES == 3
751 	{
752 		.name = "atmel-ssc-dai.1",
753 		.probe = atmel_ssc_probe,
754 		.remove = atmel_ssc_remove,
755 		.suspend = atmel_ssc_suspend,
756 		.resume = atmel_ssc_resume,
757 		.playback = {
758 			.channels_min = 1,
759 			.channels_max = 2,
760 			.rates = ATMEL_SSC_RATES,
761 			.formats = ATMEL_SSC_FORMATS,},
762 		.capture = {
763 			.channels_min = 1,
764 			.channels_max = 2,
765 			.rates = ATMEL_SSC_RATES,
766 			.formats = ATMEL_SSC_FORMATS,},
767 		.ops = &atmel_ssc_dai_ops,
768 	},
769 	{
770 		.name = "atmel-ssc-dai.2",
771 		.probe = atmel_ssc_probe,
772 		.remove = atmel_ssc_remove,
773 		.suspend = atmel_ssc_suspend,
774 		.resume = atmel_ssc_resume,
775 		.playback = {
776 			.channels_min = 1,
777 			.channels_max = 2,
778 			.rates = ATMEL_SSC_RATES,
779 			.formats = ATMEL_SSC_FORMATS,},
780 		.capture = {
781 			.channels_min = 1,
782 			.channels_max = 2,
783 			.rates = ATMEL_SSC_RATES,
784 			.formats = ATMEL_SSC_FORMATS,},
785 		.ops = &atmel_ssc_dai_ops,
786 	},
787 #endif
788 };
789 
asoc_ssc_probe(struct platform_device * pdev)790 static __devinit int asoc_ssc_probe(struct platform_device *pdev)
791 {
792 	BUG_ON(pdev->id < 0);
793 	BUG_ON(pdev->id >= ARRAY_SIZE(atmel_ssc_dai));
794 	return snd_soc_register_dai(&pdev->dev, &atmel_ssc_dai[pdev->id]);
795 }
796 
asoc_ssc_remove(struct platform_device * pdev)797 static int __devexit asoc_ssc_remove(struct platform_device *pdev)
798 {
799 	snd_soc_unregister_dai(&pdev->dev);
800 	return 0;
801 }
802 
803 static struct platform_driver asoc_ssc_driver = {
804 	.driver = {
805 			.name = "atmel-ssc-dai",
806 			.owner = THIS_MODULE,
807 	},
808 
809 	.probe = asoc_ssc_probe,
810 	.remove = __devexit_p(asoc_ssc_remove),
811 };
812 
813 /**
814  * atmel_ssc_set_audio - Allocate the specified SSC for audio use.
815  */
atmel_ssc_set_audio(int ssc_id)816 int atmel_ssc_set_audio(int ssc_id)
817 {
818 	struct ssc_device *ssc;
819 	static struct platform_device *dma_pdev;
820 	struct platform_device *ssc_pdev;
821 	int ret;
822 
823 	if (ssc_id < 0 || ssc_id >= ARRAY_SIZE(atmel_ssc_dai))
824 		return -EINVAL;
825 
826 	/* Allocate a dummy device for DMA if we don't have one already */
827 	if (!dma_pdev) {
828 		dma_pdev = platform_device_alloc("atmel-pcm-audio", -1);
829 		if (!dma_pdev)
830 			return -ENOMEM;
831 
832 		ret = platform_device_add(dma_pdev);
833 		if (ret < 0) {
834 			platform_device_put(dma_pdev);
835 			dma_pdev = NULL;
836 			return ret;
837 		}
838 	}
839 
840 	ssc_pdev = platform_device_alloc("atmel-ssc-dai", ssc_id);
841 	if (!ssc_pdev)
842 		return -ENOMEM;
843 
844 	/* If we can grab the SSC briefly to parent the DAI device off it */
845 	ssc = ssc_request(ssc_id);
846 	if (IS_ERR(ssc))
847 		pr_warn("Unable to parent ASoC SSC DAI on SSC: %ld\n",
848 			PTR_ERR(ssc));
849 	else {
850 		ssc_pdev->dev.parent = &(ssc->pdev->dev);
851 		ssc_free(ssc);
852 	}
853 
854 	ret = platform_device_add(ssc_pdev);
855 	if (ret < 0)
856 		platform_device_put(ssc_pdev);
857 
858 	return ret;
859 }
860 EXPORT_SYMBOL_GPL(atmel_ssc_set_audio);
861 
862 module_platform_driver(asoc_ssc_driver);
863 
864 /* Module information */
865 MODULE_AUTHOR("Sedji Gaouaou, sedji.gaouaou@atmel.com, www.atmel.com");
866 MODULE_DESCRIPTION("ATMEL SSC ASoC Interface");
867 MODULE_LICENSE("GPL");
868