1 /*
2  * Rockchip PDM ALSA SoC Digital Audio Interface(DAI)  driver
3  *
4  * Copyright (C) 2017 Fuzhou Rockchip Electronics Co., Ltd
5  *
6  * This software is licensed under the terms of the GNU General Public
7  * License version 2, as published by the Free Software Foundation, and
8  * may be copied, distributed, and modified under those terms.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  */
16 
17 #include <linux/module.h>
18 #include <linux/clk.h>
19 #include <linux/of.h>
20 #include <linux/of_device.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/rational.h>
23 #include <linux/regmap.h>
24 #include <linux/reset.h>
25 #include <sound/dmaengine_pcm.h>
26 #include <sound/pcm_params.h>
27 
28 #include "rockchip_pdm.h"
29 
30 #define PDM_DMA_BURST_SIZE	(8) /* size * width: 8*4 = 32 bytes */
31 #define PDM_SIGNOFF_CLK_RATE	(100000000)
32 
33 enum rk_pdm_version {
34 	RK_PDM_RK3229,
35 	RK_PDM_RK3308,
36 };
37 
38 struct rk_pdm_dev {
39 	struct device *dev;
40 	struct clk *clk;
41 	struct clk *hclk;
42 	struct regmap *regmap;
43 	struct snd_dmaengine_dai_dma_data capture_dma_data;
44 	struct reset_control *reset;
45 	enum rk_pdm_version version;
46 };
47 
48 struct rk_pdm_clkref {
49 	unsigned int sr;
50 	unsigned int clk;
51 	unsigned int clk_out;
52 };
53 
54 struct rk_pdm_ds_ratio {
55 	unsigned int ratio;
56 	unsigned int sr;
57 };
58 
59 static struct rk_pdm_clkref clkref[] = {
60 	{ 8000, 40960000, 2048000 },
61 	{ 11025, 56448000, 2822400 },
62 	{ 12000, 61440000, 3072000 },
63 	{ 8000, 98304000, 2048000 },
64 	{ 12000, 98304000, 3072000 },
65 };
66 
67 static struct rk_pdm_ds_ratio ds_ratio[] = {
68 	{ 0, 192000 },
69 	{ 0, 176400 },
70 	{ 0, 128000 },
71 	{ 1, 96000 },
72 	{ 1, 88200 },
73 	{ 1, 64000 },
74 	{ 2, 48000 },
75 	{ 2, 44100 },
76 	{ 2, 32000 },
77 	{ 3, 24000 },
78 	{ 3, 22050 },
79 	{ 3, 16000 },
80 	{ 4, 12000 },
81 	{ 4, 11025 },
82 	{ 4, 8000 },
83 };
84 
85 static unsigned int get_pdm_clk(struct rk_pdm_dev *pdm, unsigned int sr,
86 				unsigned int *clk_src, unsigned int *clk_out)
87 {
88 	unsigned int i, count, clk, div, rate;
89 
90 	clk = 0;
91 	if (!sr)
92 		return clk;
93 
94 	count = ARRAY_SIZE(clkref);
95 	for (i = 0; i < count; i++) {
96 		if (sr % clkref[i].sr)
97 			continue;
98 		div = sr / clkref[i].sr;
99 		if ((div & (div - 1)) == 0) {
100 			*clk_out = clkref[i].clk_out;
101 			rate = clk_round_rate(pdm->clk, clkref[i].clk);
102 			if (rate != clkref[i].clk)
103 				continue;
104 			clk = clkref[i].clk;
105 			*clk_src = clkref[i].clk;
106 			break;
107 		}
108 	}
109 
110 	if (!clk) {
111 		clk = clk_round_rate(pdm->clk, PDM_SIGNOFF_CLK_RATE);
112 		*clk_src = clk;
113 	}
114 	return clk;
115 }
116 
117 static unsigned int get_pdm_ds_ratio(unsigned int sr)
118 {
119 	unsigned int i, count, ratio;
120 
121 	ratio = 0;
122 	if (!sr)
123 		return ratio;
124 
125 	count = ARRAY_SIZE(ds_ratio);
126 	for (i = 0; i < count; i++) {
127 		if (sr == ds_ratio[i].sr)
128 			ratio = ds_ratio[i].ratio;
129 	}
130 	return ratio;
131 }
132 
133 static inline struct rk_pdm_dev *to_info(struct snd_soc_dai *dai)
134 {
135 	return snd_soc_dai_get_drvdata(dai);
136 }
137 
138 static void rockchip_pdm_rxctrl(struct rk_pdm_dev *pdm, int on)
139 {
140 	if (on) {
141 		regmap_update_bits(pdm->regmap, PDM_DMA_CTRL,
142 				   PDM_DMA_RD_MSK, PDM_DMA_RD_EN);
143 		regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
144 				   PDM_RX_MASK, PDM_RX_START);
145 	} else {
146 		regmap_update_bits(pdm->regmap, PDM_DMA_CTRL,
147 				   PDM_DMA_RD_MSK, PDM_DMA_RD_DIS);
148 		regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
149 				   PDM_RX_MASK | PDM_RX_CLR_MASK,
150 				   PDM_RX_STOP | PDM_RX_CLR_WR);
151 	}
152 }
153 
154 static int rockchip_pdm_hw_params(struct snd_pcm_substream *substream,
155 				  struct snd_pcm_hw_params *params,
156 				  struct snd_soc_dai *dai)
157 {
158 	struct rk_pdm_dev *pdm = to_info(dai);
159 	unsigned int val = 0;
160 	unsigned int clk_rate, clk_div, samplerate;
161 	unsigned int clk_src, clk_out = 0;
162 	unsigned long m, n;
163 	bool change;
164 	int ret;
165 
166 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
167 		return 0;
168 
169 	samplerate = params_rate(params);
170 	clk_rate = get_pdm_clk(pdm, samplerate, &clk_src, &clk_out);
171 	if (!clk_rate)
172 		return -EINVAL;
173 
174 	ret = clk_set_rate(pdm->clk, clk_src);
175 	if (ret)
176 		return -EINVAL;
177 
178 	if (pdm->version == RK_PDM_RK3308) {
179 		rational_best_approximation(clk_out, clk_src,
180 					    GENMASK(16 - 1, 0),
181 					    GENMASK(16 - 1, 0),
182 					    &m, &n);
183 
184 		val = (m << PDM_FD_NUMERATOR_SFT) |
185 			(n << PDM_FD_DENOMINATOR_SFT);
186 		regmap_update_bits_check(pdm->regmap, PDM_CTRL1,
187 					 PDM_FD_NUMERATOR_MSK |
188 					 PDM_FD_DENOMINATOR_MSK,
189 					 val, &change);
190 		if (change) {
191 			reset_control_assert(pdm->reset);
192 			reset_control_deassert(pdm->reset);
193 			rockchip_pdm_rxctrl(pdm, 0);
194 		}
195 		clk_div = n / m;
196 		if (clk_div >= 40)
197 			val = PDM_CLK_FD_RATIO_40;
198 		else if (clk_div <= 35)
199 			val = PDM_CLK_FD_RATIO_35;
200 		else
201 			return -EINVAL;
202 		regmap_update_bits(pdm->regmap, PDM_CLK_CTRL,
203 				   PDM_CLK_FD_RATIO_MSK,
204 				   val);
205 	}
206 	val = get_pdm_ds_ratio(samplerate);
207 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_DS_RATIO_MSK, val);
208 	regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
209 			   PDM_HPF_CF_MSK, PDM_HPF_60HZ);
210 	regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
211 			   PDM_HPF_LE | PDM_HPF_RE, PDM_HPF_LE | PDM_HPF_RE);
212 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_CLK_EN, PDM_CLK_EN);
213 	if (pdm->version != RK_PDM_RK3229)
214 		regmap_update_bits(pdm->regmap, PDM_CTRL0,
215 				   PDM_MODE_MSK, PDM_MODE_LJ);
216 
217 	val = 0;
218 	switch (params_format(params)) {
219 	case SNDRV_PCM_FORMAT_S8:
220 		val |= PDM_VDW(8);
221 		break;
222 	case SNDRV_PCM_FORMAT_S16_LE:
223 		val |= PDM_VDW(16);
224 		break;
225 	case SNDRV_PCM_FORMAT_S20_3LE:
226 		val |= PDM_VDW(20);
227 		break;
228 	case SNDRV_PCM_FORMAT_S24_LE:
229 		val |= PDM_VDW(24);
230 		break;
231 	case SNDRV_PCM_FORMAT_S32_LE:
232 		val |= PDM_VDW(32);
233 		break;
234 	default:
235 		return -EINVAL;
236 	}
237 
238 	switch (params_channels(params)) {
239 	case 8:
240 		val |= PDM_PATH3_EN;
241 		/* fallthrough */
242 	case 6:
243 		val |= PDM_PATH2_EN;
244 		/* fallthrough */
245 	case 4:
246 		val |= PDM_PATH1_EN;
247 		/* fallthrough */
248 	case 2:
249 		val |= PDM_PATH0_EN;
250 		break;
251 	default:
252 		dev_err(pdm->dev, "invalid channel: %d\n",
253 			params_channels(params));
254 		return -EINVAL;
255 	}
256 
257 	regmap_update_bits(pdm->regmap, PDM_CTRL0,
258 			   PDM_PATH_MSK | PDM_VDW_MSK,
259 			   val);
260 	/* all channels share the single FIFO */
261 	regmap_update_bits(pdm->regmap, PDM_DMA_CTRL, PDM_DMA_RDL_MSK,
262 			   PDM_DMA_RDL(8 * params_channels(params)));
263 
264 	return 0;
265 }
266 
267 static int rockchip_pdm_set_fmt(struct snd_soc_dai *cpu_dai,
268 				unsigned int fmt)
269 {
270 	struct rk_pdm_dev *pdm = to_info(cpu_dai);
271 	unsigned int mask = 0, val = 0;
272 
273 	mask = PDM_CKP_MSK;
274 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
275 	case SND_SOC_DAIFMT_NB_NF:
276 		val = PDM_CKP_NORMAL;
277 		break;
278 	case SND_SOC_DAIFMT_IB_NF:
279 		val = PDM_CKP_INVERTED;
280 		break;
281 	default:
282 		return -EINVAL;
283 	}
284 
285 	pm_runtime_get_sync(cpu_dai->dev);
286 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, mask, val);
287 	pm_runtime_put(cpu_dai->dev);
288 
289 	return 0;
290 }
291 
292 static int rockchip_pdm_trigger(struct snd_pcm_substream *substream, int cmd,
293 				struct snd_soc_dai *dai)
294 {
295 	struct rk_pdm_dev *pdm = to_info(dai);
296 	int ret = 0;
297 
298 	switch (cmd) {
299 	case SNDRV_PCM_TRIGGER_START:
300 	case SNDRV_PCM_TRIGGER_RESUME:
301 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
302 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
303 			rockchip_pdm_rxctrl(pdm, 1);
304 		break;
305 	case SNDRV_PCM_TRIGGER_SUSPEND:
306 	case SNDRV_PCM_TRIGGER_STOP:
307 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
308 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
309 			rockchip_pdm_rxctrl(pdm, 0);
310 		break;
311 	default:
312 		ret = -EINVAL;
313 		break;
314 	}
315 
316 	return ret;
317 }
318 
319 static int rockchip_pdm_dai_probe(struct snd_soc_dai *dai)
320 {
321 	struct rk_pdm_dev *pdm = to_info(dai);
322 
323 	dai->capture_dma_data = &pdm->capture_dma_data;
324 
325 	return 0;
326 }
327 
328 static const struct snd_soc_dai_ops rockchip_pdm_dai_ops = {
329 	.set_fmt = rockchip_pdm_set_fmt,
330 	.trigger = rockchip_pdm_trigger,
331 	.hw_params = rockchip_pdm_hw_params,
332 };
333 
334 #define ROCKCHIP_PDM_RATES SNDRV_PCM_RATE_8000_192000
335 #define ROCKCHIP_PDM_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
336 			      SNDRV_PCM_FMTBIT_S20_3LE | \
337 			      SNDRV_PCM_FMTBIT_S24_LE | \
338 			      SNDRV_PCM_FMTBIT_S32_LE)
339 
340 static struct snd_soc_dai_driver rockchip_pdm_dai = {
341 	.probe = rockchip_pdm_dai_probe,
342 	.capture = {
343 		.stream_name = "Capture",
344 		.channels_min = 2,
345 		.channels_max = 8,
346 		.rates = ROCKCHIP_PDM_RATES,
347 		.formats = ROCKCHIP_PDM_FORMATS,
348 	},
349 	.ops = &rockchip_pdm_dai_ops,
350 	.symmetric_rates = 1,
351 };
352 
353 static const struct snd_soc_component_driver rockchip_pdm_component = {
354 	.name = "rockchip-pdm",
355 };
356 
357 static int rockchip_pdm_runtime_suspend(struct device *dev)
358 {
359 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
360 
361 	clk_disable_unprepare(pdm->clk);
362 	clk_disable_unprepare(pdm->hclk);
363 
364 	return 0;
365 }
366 
367 static int rockchip_pdm_runtime_resume(struct device *dev)
368 {
369 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
370 	int ret;
371 
372 	ret = clk_prepare_enable(pdm->clk);
373 	if (ret) {
374 		dev_err(pdm->dev, "clock enable failed %d\n", ret);
375 		return ret;
376 	}
377 
378 	ret = clk_prepare_enable(pdm->hclk);
379 	if (ret) {
380 		dev_err(pdm->dev, "hclock enable failed %d\n", ret);
381 		return ret;
382 	}
383 
384 	return 0;
385 }
386 
387 static bool rockchip_pdm_wr_reg(struct device *dev, unsigned int reg)
388 {
389 	switch (reg) {
390 	case PDM_SYSCONFIG:
391 	case PDM_CTRL0:
392 	case PDM_CTRL1:
393 	case PDM_CLK_CTRL:
394 	case PDM_HPF_CTRL:
395 	case PDM_FIFO_CTRL:
396 	case PDM_DMA_CTRL:
397 	case PDM_INT_EN:
398 	case PDM_INT_CLR:
399 	case PDM_DATA_VALID:
400 		return true;
401 	default:
402 		return false;
403 	}
404 }
405 
406 static bool rockchip_pdm_rd_reg(struct device *dev, unsigned int reg)
407 {
408 	switch (reg) {
409 	case PDM_SYSCONFIG:
410 	case PDM_CTRL0:
411 	case PDM_CTRL1:
412 	case PDM_CLK_CTRL:
413 	case PDM_HPF_CTRL:
414 	case PDM_FIFO_CTRL:
415 	case PDM_DMA_CTRL:
416 	case PDM_INT_EN:
417 	case PDM_INT_CLR:
418 	case PDM_INT_ST:
419 	case PDM_DATA_VALID:
420 	case PDM_RXFIFO_DATA:
421 	case PDM_VERSION:
422 		return true;
423 	default:
424 		return false;
425 	}
426 }
427 
428 static bool rockchip_pdm_volatile_reg(struct device *dev, unsigned int reg)
429 {
430 	switch (reg) {
431 	case PDM_SYSCONFIG:
432 	case PDM_FIFO_CTRL:
433 	case PDM_INT_CLR:
434 	case PDM_INT_ST:
435 	case PDM_RXFIFO_DATA:
436 		return true;
437 	default:
438 		return false;
439 	}
440 }
441 
442 static bool rockchip_pdm_precious_reg(struct device *dev, unsigned int reg)
443 {
444 	switch (reg) {
445 	case PDM_RXFIFO_DATA:
446 		return true;
447 	default:
448 		return false;
449 	}
450 }
451 
452 static const struct reg_default rockchip_pdm_reg_defaults[] = {
453 	{0x04, 0x78000017},
454 	{0x08, 0x0bb8ea60},
455 	{0x18, 0x0000001f},
456 };
457 
458 static const struct regmap_config rockchip_pdm_regmap_config = {
459 	.reg_bits = 32,
460 	.reg_stride = 4,
461 	.val_bits = 32,
462 	.max_register = PDM_VERSION,
463 	.reg_defaults = rockchip_pdm_reg_defaults,
464 	.num_reg_defaults = ARRAY_SIZE(rockchip_pdm_reg_defaults),
465 	.writeable_reg = rockchip_pdm_wr_reg,
466 	.readable_reg = rockchip_pdm_rd_reg,
467 	.volatile_reg = rockchip_pdm_volatile_reg,
468 	.precious_reg = rockchip_pdm_precious_reg,
469 	.cache_type = REGCACHE_FLAT,
470 };
471 
472 static const struct of_device_id rockchip_pdm_match[] = {
473 	{ .compatible = "rockchip,pdm",
474 	  .data = (void *)RK_PDM_RK3229 },
475 	{ .compatible = "rockchip,px30-pdm",
476 	  .data = (void *)RK_PDM_RK3308 },
477 	{ .compatible = "rockchip,rk1808-pdm",
478 	  .data = (void *)RK_PDM_RK3308 },
479 	{ .compatible = "rockchip,rk3308-pdm",
480 	  .data = (void *)RK_PDM_RK3308 },
481 	{},
482 };
483 MODULE_DEVICE_TABLE(of, rockchip_pdm_match);
484 
485 static int rockchip_pdm_probe(struct platform_device *pdev)
486 {
487 	const struct of_device_id *match;
488 	struct rk_pdm_dev *pdm;
489 	struct resource *res;
490 	void __iomem *regs;
491 	int ret;
492 
493 	pdm = devm_kzalloc(&pdev->dev, sizeof(*pdm), GFP_KERNEL);
494 	if (!pdm)
495 		return -ENOMEM;
496 
497 	match = of_match_device(rockchip_pdm_match, &pdev->dev);
498 	if (match)
499 		pdm->version = (enum rk_pdm_version)match->data;
500 
501 	if (pdm->version == RK_PDM_RK3308) {
502 		pdm->reset = devm_reset_control_get(&pdev->dev, "pdm-m");
503 		if (IS_ERR(pdm->reset))
504 			return PTR_ERR(pdm->reset);
505 	}
506 
507 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
508 	regs = devm_ioremap_resource(&pdev->dev, res);
509 	if (IS_ERR(regs))
510 		return PTR_ERR(regs);
511 
512 	pdm->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
513 					    &rockchip_pdm_regmap_config);
514 	if (IS_ERR(pdm->regmap))
515 		return PTR_ERR(pdm->regmap);
516 
517 	pdm->capture_dma_data.addr = res->start + PDM_RXFIFO_DATA;
518 	pdm->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
519 	pdm->capture_dma_data.maxburst = PDM_DMA_BURST_SIZE;
520 
521 	pdm->dev = &pdev->dev;
522 	dev_set_drvdata(&pdev->dev, pdm);
523 
524 	pdm->clk = devm_clk_get(&pdev->dev, "pdm_clk");
525 	if (IS_ERR(pdm->clk))
526 		return PTR_ERR(pdm->clk);
527 
528 	pdm->hclk = devm_clk_get(&pdev->dev, "pdm_hclk");
529 	if (IS_ERR(pdm->hclk))
530 		return PTR_ERR(pdm->hclk);
531 
532 	ret = clk_prepare_enable(pdm->hclk);
533 	if (ret)
534 		return ret;
535 
536 	pm_runtime_enable(&pdev->dev);
537 	if (!pm_runtime_enabled(&pdev->dev)) {
538 		ret = rockchip_pdm_runtime_resume(&pdev->dev);
539 		if (ret)
540 			goto err_pm_disable;
541 	}
542 
543 	ret = devm_snd_soc_register_component(&pdev->dev,
544 					      &rockchip_pdm_component,
545 					      &rockchip_pdm_dai, 1);
546 
547 	if (ret) {
548 		dev_err(&pdev->dev, "could not register dai: %d\n", ret);
549 		goto err_suspend;
550 	}
551 
552 	rockchip_pdm_rxctrl(pdm, 0);
553 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
554 	if (ret) {
555 		dev_err(&pdev->dev, "could not register pcm: %d\n", ret);
556 		goto err_suspend;
557 	}
558 
559 	return 0;
560 
561 err_suspend:
562 	if (!pm_runtime_status_suspended(&pdev->dev))
563 		rockchip_pdm_runtime_suspend(&pdev->dev);
564 err_pm_disable:
565 	pm_runtime_disable(&pdev->dev);
566 
567 	clk_disable_unprepare(pdm->hclk);
568 
569 	return ret;
570 }
571 
572 static int rockchip_pdm_remove(struct platform_device *pdev)
573 {
574 	struct rk_pdm_dev *pdm = dev_get_drvdata(&pdev->dev);
575 
576 	pm_runtime_disable(&pdev->dev);
577 	if (!pm_runtime_status_suspended(&pdev->dev))
578 		rockchip_pdm_runtime_suspend(&pdev->dev);
579 
580 	clk_disable_unprepare(pdm->clk);
581 	clk_disable_unprepare(pdm->hclk);
582 
583 	return 0;
584 }
585 
586 #ifdef CONFIG_PM_SLEEP
587 static int rockchip_pdm_suspend(struct device *dev)
588 {
589 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
590 
591 	regcache_mark_dirty(pdm->regmap);
592 
593 	return 0;
594 }
595 
596 static int rockchip_pdm_resume(struct device *dev)
597 {
598 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
599 	int ret;
600 
601 	ret = pm_runtime_get_sync(dev);
602 	if (ret < 0)
603 		return ret;
604 
605 	ret = regcache_sync(pdm->regmap);
606 
607 	pm_runtime_put(dev);
608 
609 	return ret;
610 }
611 #endif
612 
613 static const struct dev_pm_ops rockchip_pdm_pm_ops = {
614 	SET_RUNTIME_PM_OPS(rockchip_pdm_runtime_suspend,
615 			   rockchip_pdm_runtime_resume, NULL)
616 	SET_SYSTEM_SLEEP_PM_OPS(rockchip_pdm_suspend, rockchip_pdm_resume)
617 };
618 
619 static struct platform_driver rockchip_pdm_driver = {
620 	.probe  = rockchip_pdm_probe,
621 	.remove = rockchip_pdm_remove,
622 	.driver = {
623 		.name = "rockchip-pdm",
624 		.of_match_table = of_match_ptr(rockchip_pdm_match),
625 		.pm = &rockchip_pdm_pm_ops,
626 	},
627 };
628 
629 module_platform_driver(rockchip_pdm_driver);
630 
631 MODULE_AUTHOR("Sugar <sugar.zhang@rock-chips.com>");
632 MODULE_DESCRIPTION("Rockchip PDM Controller Driver");
633 MODULE_LICENSE("GPL v2");
634