1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Rockchip PDM ALSA SoC Digital Audio Interface(DAI)  driver
4  *
5  * Copyright (C) 2017 Fuzhou Rockchip Electronics Co., Ltd
6  */
7 
8 #include <linux/module.h>
9 #include <linux/clk.h>
10 #include <linux/of.h>
11 #include <linux/of_device.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/rational.h>
14 #include <linux/regmap.h>
15 #include <linux/reset.h>
16 #include <sound/dmaengine_pcm.h>
17 #include <sound/pcm_params.h>
18 
19 #include "rockchip_pdm.h"
20 
21 #define PDM_DMA_BURST_SIZE	(8) /* size * width: 8*4 = 32 bytes */
22 #define PDM_SIGNOFF_CLK_RATE	(100000000)
23 
24 enum rk_pdm_version {
25 	RK_PDM_RK3229,
26 	RK_PDM_RK3308,
27 };
28 
29 struct rk_pdm_dev {
30 	struct device *dev;
31 	struct clk *clk;
32 	struct clk *hclk;
33 	struct regmap *regmap;
34 	struct snd_dmaengine_dai_dma_data capture_dma_data;
35 	struct reset_control *reset;
36 	enum rk_pdm_version version;
37 };
38 
39 struct rk_pdm_clkref {
40 	unsigned int sr;
41 	unsigned int clk;
42 	unsigned int clk_out;
43 };
44 
45 struct rk_pdm_ds_ratio {
46 	unsigned int ratio;
47 	unsigned int sr;
48 };
49 
50 static struct rk_pdm_clkref clkref[] = {
51 	{ 8000, 40960000, 2048000 },
52 	{ 11025, 56448000, 2822400 },
53 	{ 12000, 61440000, 3072000 },
54 	{ 8000, 98304000, 2048000 },
55 	{ 12000, 98304000, 3072000 },
56 };
57 
58 static struct rk_pdm_ds_ratio ds_ratio[] = {
59 	{ 0, 192000 },
60 	{ 0, 176400 },
61 	{ 0, 128000 },
62 	{ 1, 96000 },
63 	{ 1, 88200 },
64 	{ 1, 64000 },
65 	{ 2, 48000 },
66 	{ 2, 44100 },
67 	{ 2, 32000 },
68 	{ 3, 24000 },
69 	{ 3, 22050 },
70 	{ 3, 16000 },
71 	{ 4, 12000 },
72 	{ 4, 11025 },
73 	{ 4, 8000 },
74 };
75 
76 static unsigned int get_pdm_clk(struct rk_pdm_dev *pdm, unsigned int sr,
77 				unsigned int *clk_src, unsigned int *clk_out)
78 {
79 	unsigned int i, count, clk, div, rate;
80 
81 	clk = 0;
82 	if (!sr)
83 		return clk;
84 
85 	count = ARRAY_SIZE(clkref);
86 	for (i = 0; i < count; i++) {
87 		if (sr % clkref[i].sr)
88 			continue;
89 		div = sr / clkref[i].sr;
90 		if ((div & (div - 1)) == 0) {
91 			*clk_out = clkref[i].clk_out;
92 			rate = clk_round_rate(pdm->clk, clkref[i].clk);
93 			if (rate != clkref[i].clk)
94 				continue;
95 			clk = clkref[i].clk;
96 			*clk_src = clkref[i].clk;
97 			break;
98 		}
99 	}
100 
101 	if (!clk) {
102 		clk = clk_round_rate(pdm->clk, PDM_SIGNOFF_CLK_RATE);
103 		*clk_src = clk;
104 	}
105 	return clk;
106 }
107 
108 static unsigned int get_pdm_ds_ratio(unsigned int sr)
109 {
110 	unsigned int i, count, ratio;
111 
112 	ratio = 0;
113 	if (!sr)
114 		return ratio;
115 
116 	count = ARRAY_SIZE(ds_ratio);
117 	for (i = 0; i < count; i++) {
118 		if (sr == ds_ratio[i].sr)
119 			ratio = ds_ratio[i].ratio;
120 	}
121 	return ratio;
122 }
123 
124 static inline struct rk_pdm_dev *to_info(struct snd_soc_dai *dai)
125 {
126 	return snd_soc_dai_get_drvdata(dai);
127 }
128 
129 static void rockchip_pdm_rxctrl(struct rk_pdm_dev *pdm, int on)
130 {
131 	if (on) {
132 		regmap_update_bits(pdm->regmap, PDM_DMA_CTRL,
133 				   PDM_DMA_RD_MSK, PDM_DMA_RD_EN);
134 		regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
135 				   PDM_RX_MASK, PDM_RX_START);
136 	} else {
137 		regmap_update_bits(pdm->regmap, PDM_DMA_CTRL,
138 				   PDM_DMA_RD_MSK, PDM_DMA_RD_DIS);
139 		regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
140 				   PDM_RX_MASK | PDM_RX_CLR_MASK,
141 				   PDM_RX_STOP | PDM_RX_CLR_WR);
142 	}
143 }
144 
145 static int rockchip_pdm_hw_params(struct snd_pcm_substream *substream,
146 				  struct snd_pcm_hw_params *params,
147 				  struct snd_soc_dai *dai)
148 {
149 	struct rk_pdm_dev *pdm = to_info(dai);
150 	unsigned int val = 0;
151 	unsigned int clk_rate, clk_div, samplerate;
152 	unsigned int clk_src, clk_out = 0;
153 	unsigned long m, n;
154 	bool change;
155 	int ret;
156 
157 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
158 		return 0;
159 
160 	samplerate = params_rate(params);
161 	clk_rate = get_pdm_clk(pdm, samplerate, &clk_src, &clk_out);
162 	if (!clk_rate)
163 		return -EINVAL;
164 
165 	ret = clk_set_rate(pdm->clk, clk_src);
166 	if (ret)
167 		return -EINVAL;
168 
169 	if (pdm->version == RK_PDM_RK3308) {
170 		rational_best_approximation(clk_out, clk_src,
171 					    GENMASK(16 - 1, 0),
172 					    GENMASK(16 - 1, 0),
173 					    &m, &n);
174 
175 		val = (m << PDM_FD_NUMERATOR_SFT) |
176 			(n << PDM_FD_DENOMINATOR_SFT);
177 		regmap_update_bits_check(pdm->regmap, PDM_CTRL1,
178 					 PDM_FD_NUMERATOR_MSK |
179 					 PDM_FD_DENOMINATOR_MSK,
180 					 val, &change);
181 		if (change) {
182 			reset_control_assert(pdm->reset);
183 			reset_control_deassert(pdm->reset);
184 			rockchip_pdm_rxctrl(pdm, 0);
185 		}
186 		clk_div = n / m;
187 		if (clk_div >= 40)
188 			val = PDM_CLK_FD_RATIO_40;
189 		else if (clk_div <= 35)
190 			val = PDM_CLK_FD_RATIO_35;
191 		else
192 			return -EINVAL;
193 		regmap_update_bits(pdm->regmap, PDM_CLK_CTRL,
194 				   PDM_CLK_FD_RATIO_MSK,
195 				   val);
196 	}
197 	val = get_pdm_ds_ratio(samplerate);
198 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_DS_RATIO_MSK, val);
199 	regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
200 			   PDM_HPF_CF_MSK, PDM_HPF_60HZ);
201 	regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
202 			   PDM_HPF_LE | PDM_HPF_RE, PDM_HPF_LE | PDM_HPF_RE);
203 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_CLK_EN, PDM_CLK_EN);
204 	if (pdm->version != RK_PDM_RK3229)
205 		regmap_update_bits(pdm->regmap, PDM_CTRL0,
206 				   PDM_MODE_MSK, PDM_MODE_LJ);
207 
208 	val = 0;
209 	switch (params_format(params)) {
210 	case SNDRV_PCM_FORMAT_S8:
211 		val |= PDM_VDW(8);
212 		break;
213 	case SNDRV_PCM_FORMAT_S16_LE:
214 		val |= PDM_VDW(16);
215 		break;
216 	case SNDRV_PCM_FORMAT_S20_3LE:
217 		val |= PDM_VDW(20);
218 		break;
219 	case SNDRV_PCM_FORMAT_S24_LE:
220 		val |= PDM_VDW(24);
221 		break;
222 	case SNDRV_PCM_FORMAT_S32_LE:
223 		val |= PDM_VDW(32);
224 		break;
225 	default:
226 		return -EINVAL;
227 	}
228 
229 	switch (params_channels(params)) {
230 	case 8:
231 		val |= PDM_PATH3_EN;
232 		fallthrough;
233 	case 6:
234 		val |= PDM_PATH2_EN;
235 		fallthrough;
236 	case 4:
237 		val |= PDM_PATH1_EN;
238 		fallthrough;
239 	case 2:
240 		val |= PDM_PATH0_EN;
241 		break;
242 	default:
243 		dev_err(pdm->dev, "invalid channel: %d\n",
244 			params_channels(params));
245 		return -EINVAL;
246 	}
247 
248 	regmap_update_bits(pdm->regmap, PDM_CTRL0,
249 			   PDM_PATH_MSK | PDM_VDW_MSK,
250 			   val);
251 	/* all channels share the single FIFO */
252 	regmap_update_bits(pdm->regmap, PDM_DMA_CTRL, PDM_DMA_RDL_MSK,
253 			   PDM_DMA_RDL(8 * params_channels(params)));
254 
255 	return 0;
256 }
257 
258 static int rockchip_pdm_set_fmt(struct snd_soc_dai *cpu_dai,
259 				unsigned int fmt)
260 {
261 	struct rk_pdm_dev *pdm = to_info(cpu_dai);
262 	unsigned int mask = 0, val = 0;
263 
264 	mask = PDM_CKP_MSK;
265 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
266 	case SND_SOC_DAIFMT_NB_NF:
267 		val = PDM_CKP_NORMAL;
268 		break;
269 	case SND_SOC_DAIFMT_IB_NF:
270 		val = PDM_CKP_INVERTED;
271 		break;
272 	default:
273 		return -EINVAL;
274 	}
275 
276 	pm_runtime_get_sync(cpu_dai->dev);
277 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, mask, val);
278 	pm_runtime_put(cpu_dai->dev);
279 
280 	return 0;
281 }
282 
283 static int rockchip_pdm_trigger(struct snd_pcm_substream *substream, int cmd,
284 				struct snd_soc_dai *dai)
285 {
286 	struct rk_pdm_dev *pdm = to_info(dai);
287 	int ret = 0;
288 
289 	switch (cmd) {
290 	case SNDRV_PCM_TRIGGER_START:
291 	case SNDRV_PCM_TRIGGER_RESUME:
292 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
293 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
294 			rockchip_pdm_rxctrl(pdm, 1);
295 		break;
296 	case SNDRV_PCM_TRIGGER_SUSPEND:
297 	case SNDRV_PCM_TRIGGER_STOP:
298 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
299 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
300 			rockchip_pdm_rxctrl(pdm, 0);
301 		break;
302 	default:
303 		ret = -EINVAL;
304 		break;
305 	}
306 
307 	return ret;
308 }
309 
310 static int rockchip_pdm_dai_probe(struct snd_soc_dai *dai)
311 {
312 	struct rk_pdm_dev *pdm = to_info(dai);
313 
314 	dai->capture_dma_data = &pdm->capture_dma_data;
315 
316 	return 0;
317 }
318 
319 static const struct snd_soc_dai_ops rockchip_pdm_dai_ops = {
320 	.set_fmt = rockchip_pdm_set_fmt,
321 	.trigger = rockchip_pdm_trigger,
322 	.hw_params = rockchip_pdm_hw_params,
323 };
324 
325 #define ROCKCHIP_PDM_RATES SNDRV_PCM_RATE_8000_192000
326 #define ROCKCHIP_PDM_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
327 			      SNDRV_PCM_FMTBIT_S20_3LE | \
328 			      SNDRV_PCM_FMTBIT_S24_LE | \
329 			      SNDRV_PCM_FMTBIT_S32_LE)
330 
331 static struct snd_soc_dai_driver rockchip_pdm_dai = {
332 	.probe = rockchip_pdm_dai_probe,
333 	.capture = {
334 		.stream_name = "Capture",
335 		.channels_min = 2,
336 		.channels_max = 8,
337 		.rates = ROCKCHIP_PDM_RATES,
338 		.formats = ROCKCHIP_PDM_FORMATS,
339 	},
340 	.ops = &rockchip_pdm_dai_ops,
341 	.symmetric_rate = 1,
342 };
343 
344 static const struct snd_soc_component_driver rockchip_pdm_component = {
345 	.name = "rockchip-pdm",
346 };
347 
348 static int rockchip_pdm_runtime_suspend(struct device *dev)
349 {
350 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
351 
352 	clk_disable_unprepare(pdm->clk);
353 	clk_disable_unprepare(pdm->hclk);
354 
355 	return 0;
356 }
357 
358 static int rockchip_pdm_runtime_resume(struct device *dev)
359 {
360 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
361 	int ret;
362 
363 	ret = clk_prepare_enable(pdm->clk);
364 	if (ret) {
365 		dev_err(pdm->dev, "clock enable failed %d\n", ret);
366 		return ret;
367 	}
368 
369 	ret = clk_prepare_enable(pdm->hclk);
370 	if (ret) {
371 		dev_err(pdm->dev, "hclock enable failed %d\n", ret);
372 		return ret;
373 	}
374 
375 	return 0;
376 }
377 
378 static bool rockchip_pdm_wr_reg(struct device *dev, unsigned int reg)
379 {
380 	switch (reg) {
381 	case PDM_SYSCONFIG:
382 	case PDM_CTRL0:
383 	case PDM_CTRL1:
384 	case PDM_CLK_CTRL:
385 	case PDM_HPF_CTRL:
386 	case PDM_FIFO_CTRL:
387 	case PDM_DMA_CTRL:
388 	case PDM_INT_EN:
389 	case PDM_INT_CLR:
390 	case PDM_DATA_VALID:
391 		return true;
392 	default:
393 		return false;
394 	}
395 }
396 
397 static bool rockchip_pdm_rd_reg(struct device *dev, unsigned int reg)
398 {
399 	switch (reg) {
400 	case PDM_SYSCONFIG:
401 	case PDM_CTRL0:
402 	case PDM_CTRL1:
403 	case PDM_CLK_CTRL:
404 	case PDM_HPF_CTRL:
405 	case PDM_FIFO_CTRL:
406 	case PDM_DMA_CTRL:
407 	case PDM_INT_EN:
408 	case PDM_INT_CLR:
409 	case PDM_INT_ST:
410 	case PDM_DATA_VALID:
411 	case PDM_RXFIFO_DATA:
412 	case PDM_VERSION:
413 		return true;
414 	default:
415 		return false;
416 	}
417 }
418 
419 static bool rockchip_pdm_volatile_reg(struct device *dev, unsigned int reg)
420 {
421 	switch (reg) {
422 	case PDM_SYSCONFIG:
423 	case PDM_FIFO_CTRL:
424 	case PDM_INT_CLR:
425 	case PDM_INT_ST:
426 	case PDM_RXFIFO_DATA:
427 		return true;
428 	default:
429 		return false;
430 	}
431 }
432 
433 static bool rockchip_pdm_precious_reg(struct device *dev, unsigned int reg)
434 {
435 	switch (reg) {
436 	case PDM_RXFIFO_DATA:
437 		return true;
438 	default:
439 		return false;
440 	}
441 }
442 
443 static const struct reg_default rockchip_pdm_reg_defaults[] = {
444 	{0x04, 0x78000017},
445 	{0x08, 0x0bb8ea60},
446 	{0x18, 0x0000001f},
447 };
448 
449 static const struct regmap_config rockchip_pdm_regmap_config = {
450 	.reg_bits = 32,
451 	.reg_stride = 4,
452 	.val_bits = 32,
453 	.max_register = PDM_VERSION,
454 	.reg_defaults = rockchip_pdm_reg_defaults,
455 	.num_reg_defaults = ARRAY_SIZE(rockchip_pdm_reg_defaults),
456 	.writeable_reg = rockchip_pdm_wr_reg,
457 	.readable_reg = rockchip_pdm_rd_reg,
458 	.volatile_reg = rockchip_pdm_volatile_reg,
459 	.precious_reg = rockchip_pdm_precious_reg,
460 	.cache_type = REGCACHE_FLAT,
461 };
462 
463 static const struct of_device_id rockchip_pdm_match[] __maybe_unused = {
464 	{ .compatible = "rockchip,pdm",
465 	  .data = (void *)RK_PDM_RK3229 },
466 	{ .compatible = "rockchip,px30-pdm",
467 	  .data = (void *)RK_PDM_RK3308 },
468 	{ .compatible = "rockchip,rk1808-pdm",
469 	  .data = (void *)RK_PDM_RK3308 },
470 	{ .compatible = "rockchip,rk3308-pdm",
471 	  .data = (void *)RK_PDM_RK3308 },
472 	{},
473 };
474 MODULE_DEVICE_TABLE(of, rockchip_pdm_match);
475 
476 static int rockchip_pdm_probe(struct platform_device *pdev)
477 {
478 	const struct of_device_id *match;
479 	struct rk_pdm_dev *pdm;
480 	struct resource *res;
481 	void __iomem *regs;
482 	int ret;
483 
484 	pdm = devm_kzalloc(&pdev->dev, sizeof(*pdm), GFP_KERNEL);
485 	if (!pdm)
486 		return -ENOMEM;
487 
488 	match = of_match_device(rockchip_pdm_match, &pdev->dev);
489 	if (match)
490 		pdm->version = (enum rk_pdm_version)match->data;
491 
492 	if (pdm->version == RK_PDM_RK3308) {
493 		pdm->reset = devm_reset_control_get(&pdev->dev, "pdm-m");
494 		if (IS_ERR(pdm->reset))
495 			return PTR_ERR(pdm->reset);
496 	}
497 
498 	regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
499 	if (IS_ERR(regs))
500 		return PTR_ERR(regs);
501 
502 	pdm->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
503 					    &rockchip_pdm_regmap_config);
504 	if (IS_ERR(pdm->regmap))
505 		return PTR_ERR(pdm->regmap);
506 
507 	pdm->capture_dma_data.addr = res->start + PDM_RXFIFO_DATA;
508 	pdm->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
509 	pdm->capture_dma_data.maxburst = PDM_DMA_BURST_SIZE;
510 
511 	pdm->dev = &pdev->dev;
512 	dev_set_drvdata(&pdev->dev, pdm);
513 
514 	pdm->clk = devm_clk_get(&pdev->dev, "pdm_clk");
515 	if (IS_ERR(pdm->clk))
516 		return PTR_ERR(pdm->clk);
517 
518 	pdm->hclk = devm_clk_get(&pdev->dev, "pdm_hclk");
519 	if (IS_ERR(pdm->hclk))
520 		return PTR_ERR(pdm->hclk);
521 
522 	ret = clk_prepare_enable(pdm->hclk);
523 	if (ret)
524 		return ret;
525 
526 	pm_runtime_enable(&pdev->dev);
527 	if (!pm_runtime_enabled(&pdev->dev)) {
528 		ret = rockchip_pdm_runtime_resume(&pdev->dev);
529 		if (ret)
530 			goto err_pm_disable;
531 	}
532 
533 	ret = devm_snd_soc_register_component(&pdev->dev,
534 					      &rockchip_pdm_component,
535 					      &rockchip_pdm_dai, 1);
536 
537 	if (ret) {
538 		dev_err(&pdev->dev, "could not register dai: %d\n", ret);
539 		goto err_suspend;
540 	}
541 
542 	rockchip_pdm_rxctrl(pdm, 0);
543 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
544 	if (ret) {
545 		dev_err(&pdev->dev, "could not register pcm: %d\n", ret);
546 		goto err_suspend;
547 	}
548 
549 	return 0;
550 
551 err_suspend:
552 	if (!pm_runtime_status_suspended(&pdev->dev))
553 		rockchip_pdm_runtime_suspend(&pdev->dev);
554 err_pm_disable:
555 	pm_runtime_disable(&pdev->dev);
556 
557 	clk_disable_unprepare(pdm->hclk);
558 
559 	return ret;
560 }
561 
562 static int rockchip_pdm_remove(struct platform_device *pdev)
563 {
564 	struct rk_pdm_dev *pdm = dev_get_drvdata(&pdev->dev);
565 
566 	pm_runtime_disable(&pdev->dev);
567 	if (!pm_runtime_status_suspended(&pdev->dev))
568 		rockchip_pdm_runtime_suspend(&pdev->dev);
569 
570 	clk_disable_unprepare(pdm->clk);
571 	clk_disable_unprepare(pdm->hclk);
572 
573 	return 0;
574 }
575 
576 #ifdef CONFIG_PM_SLEEP
577 static int rockchip_pdm_suspend(struct device *dev)
578 {
579 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
580 
581 	regcache_mark_dirty(pdm->regmap);
582 
583 	return 0;
584 }
585 
586 static int rockchip_pdm_resume(struct device *dev)
587 {
588 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
589 	int ret;
590 
591 	ret = pm_runtime_get_sync(dev);
592 	if (ret < 0) {
593 		pm_runtime_put(dev);
594 		return ret;
595 	}
596 
597 	ret = regcache_sync(pdm->regmap);
598 
599 	pm_runtime_put(dev);
600 
601 	return ret;
602 }
603 #endif
604 
605 static const struct dev_pm_ops rockchip_pdm_pm_ops = {
606 	SET_RUNTIME_PM_OPS(rockchip_pdm_runtime_suspend,
607 			   rockchip_pdm_runtime_resume, NULL)
608 	SET_SYSTEM_SLEEP_PM_OPS(rockchip_pdm_suspend, rockchip_pdm_resume)
609 };
610 
611 static struct platform_driver rockchip_pdm_driver = {
612 	.probe  = rockchip_pdm_probe,
613 	.remove = rockchip_pdm_remove,
614 	.driver = {
615 		.name = "rockchip-pdm",
616 		.of_match_table = of_match_ptr(rockchip_pdm_match),
617 		.pm = &rockchip_pdm_pm_ops,
618 	},
619 };
620 
621 module_platform_driver(rockchip_pdm_driver);
622 
623 MODULE_AUTHOR("Sugar <sugar.zhang@rock-chips.com>");
624 MODULE_DESCRIPTION("Rockchip PDM Controller Driver");
625 MODULE_LICENSE("GPL v2");
626