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

source code of linux/sound/soc/atmel/atmel_ssc_dai.c