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8#include <linux/clk.h>
9#include <linux/io.h>
10#include <linux/module.h>
11#include <linux/of.h>
12#include <linux/platform_device.h>
13#include <linux/pm_runtime.h>
14#include <sound/pcm_params.h>
15#include <sound/soc.h>
16
17#define DRV_NAME "xtfpga-i2s"
18
19#define XTFPGA_I2S_VERSION 0x00
20#define XTFPGA_I2S_CONFIG 0x04
21#define XTFPGA_I2S_INT_MASK 0x08
22#define XTFPGA_I2S_INT_STATUS 0x0c
23#define XTFPGA_I2S_CHAN0_DATA 0x10
24#define XTFPGA_I2S_CHAN1_DATA 0x14
25#define XTFPGA_I2S_CHAN2_DATA 0x18
26#define XTFPGA_I2S_CHAN3_DATA 0x1c
27
28#define XTFPGA_I2S_CONFIG_TX_ENABLE 0x1
29#define XTFPGA_I2S_CONFIG_INT_ENABLE 0x2
30#define XTFPGA_I2S_CONFIG_LEFT 0x4
31#define XTFPGA_I2S_CONFIG_RATIO_BASE 8
32#define XTFPGA_I2S_CONFIG_RATIO_MASK 0x0000ff00
33#define XTFPGA_I2S_CONFIG_RES_BASE 16
34#define XTFPGA_I2S_CONFIG_RES_MASK 0x003f0000
35#define XTFPGA_I2S_CONFIG_LEVEL_BASE 24
36#define XTFPGA_I2S_CONFIG_LEVEL_MASK 0x0f000000
37#define XTFPGA_I2S_CONFIG_CHANNEL_BASE 28
38
39#define XTFPGA_I2S_INT_UNDERRUN 0x1
40#define XTFPGA_I2S_INT_LEVEL 0x2
41#define XTFPGA_I2S_INT_VALID 0x3
42
43#define XTFPGA_I2S_FIFO_SIZE 8192
44
45
46
47
48
49
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51
52
53
54
55
56
57struct xtfpga_i2s {
58 struct device *dev;
59 struct clk *clk;
60 struct regmap *regmap;
61 void __iomem *regs;
62
63
64
65
66
67
68
69
70
71
72
73
74
75 struct snd_pcm_substream __rcu *tx_substream;
76 unsigned (*tx_fn)(struct xtfpga_i2s *i2s,
77 struct snd_pcm_runtime *runtime,
78 unsigned tx_ptr);
79 unsigned tx_ptr;
80
81
82
83
84
85 unsigned tx_fifo_level;
86
87
88 unsigned tx_fifo_low;
89
90
91 unsigned tx_fifo_high;
92};
93
94static bool xtfpga_i2s_wr_reg(struct device *dev, unsigned int reg)
95{
96 return reg >= XTFPGA_I2S_CONFIG;
97}
98
99static bool xtfpga_i2s_rd_reg(struct device *dev, unsigned int reg)
100{
101 return reg < XTFPGA_I2S_CHAN0_DATA;
102}
103
104static bool xtfpga_i2s_volatile_reg(struct device *dev, unsigned int reg)
105{
106 return reg == XTFPGA_I2S_INT_STATUS;
107}
108
109static const struct regmap_config xtfpga_i2s_regmap_config = {
110 .reg_bits = 32,
111 .reg_stride = 4,
112 .val_bits = 32,
113 .max_register = XTFPGA_I2S_CHAN3_DATA,
114 .writeable_reg = xtfpga_i2s_wr_reg,
115 .readable_reg = xtfpga_i2s_rd_reg,
116 .volatile_reg = xtfpga_i2s_volatile_reg,
117 .cache_type = REGCACHE_FLAT,
118};
119
120
121
122
123
124
125
126
127
128
129#define xtfpga_pcm_tx_fn(channels, sample_bits) \
130static unsigned xtfpga_pcm_tx_##channels##x##sample_bits( \
131 struct xtfpga_i2s *i2s, struct snd_pcm_runtime *runtime, \
132 unsigned tx_ptr) \
133{ \
134 const u##sample_bits (*p)[channels] = \
135 (void *)runtime->dma_area; \
136\
137 for (; i2s->tx_fifo_level < i2s->tx_fifo_high; \
138 i2s->tx_fifo_level += 2) { \
139 iowrite32(p[tx_ptr][0], \
140 i2s->regs + XTFPGA_I2S_CHAN0_DATA); \
141 iowrite32(p[tx_ptr][channels - 1], \
142 i2s->regs + XTFPGA_I2S_CHAN0_DATA); \
143 if (++tx_ptr >= runtime->buffer_size) \
144 tx_ptr = 0; \
145 } \
146 return tx_ptr; \
147}
148
149xtfpga_pcm_tx_fn(1, 16)
150xtfpga_pcm_tx_fn(2, 16)
151xtfpga_pcm_tx_fn(1, 32)
152xtfpga_pcm_tx_fn(2, 32)
153
154#undef xtfpga_pcm_tx_fn
155
156static bool xtfpga_pcm_push_tx(struct xtfpga_i2s *i2s)
157{
158 struct snd_pcm_substream *tx_substream;
159 bool tx_active;
160
161 rcu_read_lock();
162 tx_substream = rcu_dereference(i2s->tx_substream);
163 tx_active = tx_substream && snd_pcm_running(tx_substream);
164 if (tx_active) {
165 unsigned tx_ptr = READ_ONCE(i2s->tx_ptr);
166 unsigned new_tx_ptr = i2s->tx_fn(i2s, tx_substream->runtime,
167 tx_ptr);
168
169 cmpxchg(&i2s->tx_ptr, tx_ptr, new_tx_ptr);
170 }
171 rcu_read_unlock();
172
173 return tx_active;
174}
175
176static void xtfpga_pcm_refill_fifo(struct xtfpga_i2s *i2s)
177{
178 unsigned int_status;
179 unsigned i;
180
181 regmap_read(i2s->regmap, XTFPGA_I2S_INT_STATUS,
182 &int_status);
183
184 for (i = 0; i < 2; ++i) {
185 bool tx_active = xtfpga_pcm_push_tx(i2s);
186
187 regmap_write(i2s->regmap, XTFPGA_I2S_INT_STATUS,
188 XTFPGA_I2S_INT_VALID);
189 if (tx_active)
190 regmap_read(i2s->regmap, XTFPGA_I2S_INT_STATUS,
191 &int_status);
192
193 if (!tx_active ||
194 !(int_status & XTFPGA_I2S_INT_LEVEL))
195 break;
196
197
198
199
200
201 i2s->tx_fifo_level = i2s->tx_fifo_low;
202 }
203
204 if (!(int_status & XTFPGA_I2S_INT_LEVEL))
205 regmap_write(i2s->regmap, XTFPGA_I2S_INT_MASK,
206 XTFPGA_I2S_INT_VALID);
207 else if (!(int_status & XTFPGA_I2S_INT_UNDERRUN))
208 regmap_write(i2s->regmap, XTFPGA_I2S_INT_MASK,
209 XTFPGA_I2S_INT_UNDERRUN);
210
211 if (!(int_status & XTFPGA_I2S_INT_UNDERRUN))
212 regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
213 XTFPGA_I2S_CONFIG_INT_ENABLE |
214 XTFPGA_I2S_CONFIG_TX_ENABLE,
215 XTFPGA_I2S_CONFIG_INT_ENABLE |
216 XTFPGA_I2S_CONFIG_TX_ENABLE);
217 else
218 regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
219 XTFPGA_I2S_CONFIG_INT_ENABLE |
220 XTFPGA_I2S_CONFIG_TX_ENABLE, 0);
221}
222
223static irqreturn_t xtfpga_i2s_threaded_irq_handler(int irq, void *dev_id)
224{
225 struct xtfpga_i2s *i2s = dev_id;
226 struct snd_pcm_substream *tx_substream;
227 unsigned config, int_status, int_mask;
228
229 regmap_read(i2s->regmap, XTFPGA_I2S_CONFIG, &config);
230 regmap_read(i2s->regmap, XTFPGA_I2S_INT_MASK, &int_mask);
231 regmap_read(i2s->regmap, XTFPGA_I2S_INT_STATUS, &int_status);
232
233 if (!(config & XTFPGA_I2S_CONFIG_INT_ENABLE) ||
234 !(int_status & int_mask & XTFPGA_I2S_INT_VALID))
235 return IRQ_NONE;
236
237
238
239
240 if (int_status & XTFPGA_I2S_INT_UNDERRUN) {
241 i2s->tx_fifo_level = 0;
242 regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
243 XTFPGA_I2S_CONFIG_TX_ENABLE, 0);
244 } else {
245
246
247
248 i2s->tx_fifo_level = i2s->tx_fifo_low;
249 }
250
251 rcu_read_lock();
252 tx_substream = rcu_dereference(i2s->tx_substream);
253
254 if (tx_substream && snd_pcm_running(tx_substream)) {
255 snd_pcm_period_elapsed(tx_substream);
256 if (int_status & XTFPGA_I2S_INT_UNDERRUN)
257 dev_dbg_ratelimited(i2s->dev, "%s: underrun\n",
258 __func__);
259 }
260 rcu_read_unlock();
261
262
263
264
265 xtfpga_pcm_refill_fifo(i2s);
266
267 return IRQ_HANDLED;
268}
269
270static int xtfpga_i2s_startup(struct snd_pcm_substream *substream,
271 struct snd_soc_dai *dai)
272{
273 struct xtfpga_i2s *i2s = snd_soc_dai_get_drvdata(dai);
274
275 snd_soc_dai_set_dma_data(dai, substream, i2s);
276 return 0;
277}
278
279static int xtfpga_i2s_hw_params(struct snd_pcm_substream *substream,
280 struct snd_pcm_hw_params *params,
281 struct snd_soc_dai *dai)
282{
283 struct xtfpga_i2s *i2s = snd_soc_dai_get_drvdata(dai);
284 unsigned srate = params_rate(params);
285 unsigned channels = params_channels(params);
286 unsigned period_size = params_period_size(params);
287 unsigned sample_size = snd_pcm_format_width(params_format(params));
288 unsigned freq, ratio, level;
289 int err;
290
291 regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
292 XTFPGA_I2S_CONFIG_RES_MASK,
293 sample_size << XTFPGA_I2S_CONFIG_RES_BASE);
294
295 freq = 256 * srate;
296 err = clk_set_rate(i2s->clk, freq);
297 if (err < 0)
298 return err;
299
300
301
302
303
304
305
306 ratio = (freq - (srate * sample_size * 8)) /
307 (srate * sample_size * 4);
308
309 regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
310 XTFPGA_I2S_CONFIG_RATIO_MASK,
311 ratio << XTFPGA_I2S_CONFIG_RATIO_BASE);
312
313 i2s->tx_fifo_low = XTFPGA_I2S_FIFO_SIZE / 2;
314
315
316 for (level = 1;
317 i2s->tx_fifo_low / 2 >= period_size * 2 &&
318 level < (XTFPGA_I2S_CONFIG_LEVEL_MASK >>
319 XTFPGA_I2S_CONFIG_LEVEL_BASE); ++level)
320 i2s->tx_fifo_low /= 2;
321
322 i2s->tx_fifo_high = 2 * i2s->tx_fifo_low;
323
324 regmap_update_bits(i2s->regmap, XTFPGA_I2S_CONFIG,
325 XTFPGA_I2S_CONFIG_LEVEL_MASK,
326 level << XTFPGA_I2S_CONFIG_LEVEL_BASE);
327
328 dev_dbg(i2s->dev,
329 "%s srate: %u, channels: %u, sample_size: %u, period_size: %u\n",
330 __func__, srate, channels, sample_size, period_size);
331 dev_dbg(i2s->dev, "%s freq: %u, ratio: %u, level: %u\n",
332 __func__, freq, ratio, level);
333
334 return 0;
335}
336
337static int xtfpga_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
338 unsigned int fmt)
339{
340 if ((fmt & SND_SOC_DAIFMT_INV_MASK) != SND_SOC_DAIFMT_NB_NF)
341 return -EINVAL;
342 if ((fmt & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBS_CFS)
343 return -EINVAL;
344 if ((fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_I2S)
345 return -EINVAL;
346
347 return 0;
348}
349
350
351
352static const struct snd_pcm_hardware xtfpga_pcm_hardware = {
353 .info = SNDRV_PCM_INFO_INTERLEAVED |
354 SNDRV_PCM_INFO_MMAP_VALID |
355 SNDRV_PCM_INFO_BLOCK_TRANSFER,
356 .formats = SNDRV_PCM_FMTBIT_S16_LE |
357 SNDRV_PCM_FMTBIT_S32_LE,
358 .channels_min = 1,
359 .channels_max = 2,
360 .period_bytes_min = 2,
361 .period_bytes_max = XTFPGA_I2S_FIFO_SIZE / 2 * 8,
362 .periods_min = 2,
363 .periods_max = XTFPGA_I2S_FIFO_SIZE * 8 / 2,
364 .buffer_bytes_max = XTFPGA_I2S_FIFO_SIZE * 8,
365 .fifo_size = 16,
366};
367
368static int xtfpga_pcm_open(struct snd_pcm_substream *substream)
369{
370 struct snd_pcm_runtime *runtime = substream->runtime;
371 struct snd_soc_pcm_runtime *rtd = substream->private_data;
372 void *p;
373
374 snd_soc_set_runtime_hwparams(substream, &xtfpga_pcm_hardware);
375 p = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
376 runtime->private_data = p;
377
378 return 0;
379}
380
381static int xtfpga_pcm_close(struct snd_pcm_substream *substream)
382{
383 synchronize_rcu();
384 return 0;
385}
386
387static int xtfpga_pcm_hw_params(struct snd_pcm_substream *substream,
388 struct snd_pcm_hw_params *hw_params)
389{
390 int ret;
391 struct snd_pcm_runtime *runtime = substream->runtime;
392 struct xtfpga_i2s *i2s = runtime->private_data;
393 unsigned channels = params_channels(hw_params);
394
395 switch (channels) {
396 case 1:
397 case 2:
398 break;
399
400 default:
401 return -EINVAL;
402
403 }
404
405 switch (params_format(hw_params)) {
406 case SNDRV_PCM_FORMAT_S16_LE:
407 i2s->tx_fn = (channels == 1) ?
408 xtfpga_pcm_tx_1x16 :
409 xtfpga_pcm_tx_2x16;
410 break;
411
412 case SNDRV_PCM_FORMAT_S32_LE:
413 i2s->tx_fn = (channels == 1) ?
414 xtfpga_pcm_tx_1x32 :
415 xtfpga_pcm_tx_2x32;
416 break;
417
418 default:
419 return -EINVAL;
420 }
421
422 ret = snd_pcm_lib_malloc_pages(substream,
423 params_buffer_bytes(hw_params));
424 return ret;
425}
426
427static int xtfpga_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
428{
429 int ret = 0;
430 struct snd_pcm_runtime *runtime = substream->runtime;
431 struct xtfpga_i2s *i2s = runtime->private_data;
432
433 switch (cmd) {
434 case SNDRV_PCM_TRIGGER_START:
435 case SNDRV_PCM_TRIGGER_RESUME:
436 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
437 WRITE_ONCE(i2s->tx_ptr, 0);
438 rcu_assign_pointer(i2s->tx_substream, substream);
439 xtfpga_pcm_refill_fifo(i2s);
440 break;
441
442 case SNDRV_PCM_TRIGGER_STOP:
443 case SNDRV_PCM_TRIGGER_SUSPEND:
444 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
445 rcu_assign_pointer(i2s->tx_substream, NULL);
446 break;
447
448 default:
449 ret = -EINVAL;
450 break;
451 }
452 return ret;
453}
454
455static snd_pcm_uframes_t xtfpga_pcm_pointer(struct snd_pcm_substream *substream)
456{
457 struct snd_pcm_runtime *runtime = substream->runtime;
458 struct xtfpga_i2s *i2s = runtime->private_data;
459 snd_pcm_uframes_t pos = READ_ONCE(i2s->tx_ptr);
460
461 return pos < runtime->buffer_size ? pos : 0;
462}
463
464static int xtfpga_pcm_new(struct snd_soc_pcm_runtime *rtd)
465{
466 struct snd_card *card = rtd->card->snd_card;
467 size_t size = xtfpga_pcm_hardware.buffer_bytes_max;
468
469 snd_pcm_lib_preallocate_pages_for_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
470 card->dev, size, size);
471 return 0;
472}
473
474static const struct snd_pcm_ops xtfpga_pcm_ops = {
475 .open = xtfpga_pcm_open,
476 .close = xtfpga_pcm_close,
477 .ioctl = snd_pcm_lib_ioctl,
478 .hw_params = xtfpga_pcm_hw_params,
479 .trigger = xtfpga_pcm_trigger,
480 .pointer = xtfpga_pcm_pointer,
481};
482
483static const struct snd_soc_component_driver xtfpga_i2s_component = {
484 .name = DRV_NAME,
485 .pcm_new = xtfpga_pcm_new,
486 .ops = &xtfpga_pcm_ops,
487};
488
489static const struct snd_soc_dai_ops xtfpga_i2s_dai_ops = {
490 .startup = xtfpga_i2s_startup,
491 .hw_params = xtfpga_i2s_hw_params,
492 .set_fmt = xtfpga_i2s_set_fmt,
493};
494
495static struct snd_soc_dai_driver xtfpga_i2s_dai[] = {
496 {
497 .name = "xtfpga-i2s",
498 .id = 0,
499 .playback = {
500 .channels_min = 1,
501 .channels_max = 2,
502 .rates = SNDRV_PCM_RATE_8000_96000,
503 .formats = SNDRV_PCM_FMTBIT_S16_LE |
504 SNDRV_PCM_FMTBIT_S32_LE,
505 },
506 .ops = &xtfpga_i2s_dai_ops,
507 },
508};
509
510static int xtfpga_i2s_runtime_suspend(struct device *dev)
511{
512 struct xtfpga_i2s *i2s = dev_get_drvdata(dev);
513
514 clk_disable_unprepare(i2s->clk);
515 return 0;
516}
517
518static int xtfpga_i2s_runtime_resume(struct device *dev)
519{
520 struct xtfpga_i2s *i2s = dev_get_drvdata(dev);
521 int ret;
522
523 ret = clk_prepare_enable(i2s->clk);
524 if (ret) {
525 dev_err(dev, "clk_prepare_enable failed: %d\n", ret);
526 return ret;
527 }
528 return 0;
529}
530
531static int xtfpga_i2s_probe(struct platform_device *pdev)
532{
533 struct xtfpga_i2s *i2s;
534 struct resource *mem;
535 int err, irq;
536
537 i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
538 if (!i2s) {
539 err = -ENOMEM;
540 goto err;
541 }
542 platform_set_drvdata(pdev, i2s);
543 i2s->dev = &pdev->dev;
544 dev_dbg(&pdev->dev, "dev: %p, i2s: %p\n", &pdev->dev, i2s);
545
546 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
547 i2s->regs = devm_ioremap_resource(&pdev->dev, mem);
548 if (IS_ERR(i2s->regs)) {
549 err = PTR_ERR(i2s->regs);
550 goto err;
551 }
552
553 i2s->regmap = devm_regmap_init_mmio(&pdev->dev, i2s->regs,
554 &xtfpga_i2s_regmap_config);
555 if (IS_ERR(i2s->regmap)) {
556 dev_err(&pdev->dev, "regmap init failed\n");
557 err = PTR_ERR(i2s->regmap);
558 goto err;
559 }
560
561 i2s->clk = devm_clk_get(&pdev->dev, NULL);
562 if (IS_ERR(i2s->clk)) {
563 dev_err(&pdev->dev, "couldn't get clock\n");
564 err = PTR_ERR(i2s->clk);
565 goto err;
566 }
567
568 regmap_write(i2s->regmap, XTFPGA_I2S_CONFIG,
569 (0x1 << XTFPGA_I2S_CONFIG_CHANNEL_BASE));
570 regmap_write(i2s->regmap, XTFPGA_I2S_INT_STATUS, XTFPGA_I2S_INT_VALID);
571 regmap_write(i2s->regmap, XTFPGA_I2S_INT_MASK, XTFPGA_I2S_INT_UNDERRUN);
572
573 irq = platform_get_irq(pdev, 0);
574 if (irq < 0) {
575 dev_err(&pdev->dev, "No IRQ resource\n");
576 err = irq;
577 goto err;
578 }
579 err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
580 xtfpga_i2s_threaded_irq_handler,
581 IRQF_SHARED | IRQF_ONESHOT,
582 pdev->name, i2s);
583 if (err < 0) {
584 dev_err(&pdev->dev, "request_irq failed\n");
585 goto err;
586 }
587
588 err = devm_snd_soc_register_component(&pdev->dev,
589 &xtfpga_i2s_component,
590 xtfpga_i2s_dai,
591 ARRAY_SIZE(xtfpga_i2s_dai));
592 if (err < 0) {
593 dev_err(&pdev->dev, "couldn't register component\n");
594 goto err;
595 }
596
597 pm_runtime_enable(&pdev->dev);
598 if (!pm_runtime_enabled(&pdev->dev)) {
599 err = xtfpga_i2s_runtime_resume(&pdev->dev);
600 if (err)
601 goto err_pm_disable;
602 }
603 return 0;
604
605err_pm_disable:
606 pm_runtime_disable(&pdev->dev);
607err:
608 dev_err(&pdev->dev, "%s: err = %d\n", __func__, err);
609 return err;
610}
611
612static int xtfpga_i2s_remove(struct platform_device *pdev)
613{
614 struct xtfpga_i2s *i2s = dev_get_drvdata(&pdev->dev);
615
616 if (i2s->regmap && !IS_ERR(i2s->regmap)) {
617 regmap_write(i2s->regmap, XTFPGA_I2S_CONFIG, 0);
618 regmap_write(i2s->regmap, XTFPGA_I2S_INT_MASK, 0);
619 regmap_write(i2s->regmap, XTFPGA_I2S_INT_STATUS,
620 XTFPGA_I2S_INT_VALID);
621 }
622 pm_runtime_disable(&pdev->dev);
623 if (!pm_runtime_status_suspended(&pdev->dev))
624 xtfpga_i2s_runtime_suspend(&pdev->dev);
625 return 0;
626}
627
628#ifdef CONFIG_OF
629static const struct of_device_id xtfpga_i2s_of_match[] = {
630 { .compatible = "cdns,xtfpga-i2s", },
631 {},
632};
633MODULE_DEVICE_TABLE(of, xtfpga_i2s_of_match);
634#endif
635
636static const struct dev_pm_ops xtfpga_i2s_pm_ops = {
637 SET_RUNTIME_PM_OPS(xtfpga_i2s_runtime_suspend,
638 xtfpga_i2s_runtime_resume, NULL)
639};
640
641static struct platform_driver xtfpga_i2s_driver = {
642 .probe = xtfpga_i2s_probe,
643 .remove = xtfpga_i2s_remove,
644 .driver = {
645 .name = "xtfpga-i2s",
646 .of_match_table = of_match_ptr(xtfpga_i2s_of_match),
647 .pm = &xtfpga_i2s_pm_ops,
648 },
649};
650
651module_platform_driver(xtfpga_i2s_driver);
652
653MODULE_AUTHOR("Max Filippov <jcmvbkbc@gmail.com>");
654MODULE_DESCRIPTION("xtfpga I2S controller driver");
655MODULE_LICENSE("GPL v2");
656