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/pm_runtime.h>
21 #include <linux/regmap.h>
22 #include <sound/dmaengine_pcm.h>
23 #include <sound/pcm_params.h>
24 
25 #include "rockchip_pdm.h"
26 
27 #define PDM_DMA_BURST_SIZE	(8) /* size * width: 8*4 = 32 bytes */
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 };
36 
37 struct rk_pdm_clkref {
38 	unsigned int sr;
39 	unsigned int clk;
40 };
41 
42 static struct rk_pdm_clkref clkref[] = {
43 	{ 8000, 40960000 },
44 	{ 11025, 56448000 },
45 	{ 12000, 61440000 },
46 };
47 
48 static unsigned int get_pdm_clk(unsigned int sr)
49 {
50 	unsigned int i, count, clk, div;
51 
52 	clk = 0;
53 	if (!sr)
54 		return clk;
55 
56 	count = ARRAY_SIZE(clkref);
57 	for (i = 0; i < count; i++) {
58 		if (sr % clkref[i].sr)
59 			continue;
60 		div = sr / clkref[i].sr;
61 		if ((div & (div - 1)) == 0) {
62 			clk = clkref[i].clk;
63 			break;
64 		}
65 	}
66 
67 	return clk;
68 }
69 
70 static inline struct rk_pdm_dev *to_info(struct snd_soc_dai *dai)
71 {
72 	return snd_soc_dai_get_drvdata(dai);
73 }
74 
75 static void rockchip_pdm_rxctrl(struct rk_pdm_dev *pdm, int on)
76 {
77 	if (on) {
78 		regmap_update_bits(pdm->regmap, PDM_DMA_CTRL,
79 				   PDM_DMA_RD_MSK, PDM_DMA_RD_EN);
80 		regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
81 				   PDM_RX_MASK, PDM_RX_START);
82 	} else {
83 		regmap_update_bits(pdm->regmap, PDM_DMA_CTRL,
84 				   PDM_DMA_RD_MSK, PDM_DMA_RD_DIS);
85 		regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
86 				   PDM_RX_MASK | PDM_RX_CLR_MASK,
87 				   PDM_RX_STOP | PDM_RX_CLR_WR);
88 	}
89 }
90 
91 static int rockchip_pdm_hw_params(struct snd_pcm_substream *substream,
92 				  struct snd_pcm_hw_params *params,
93 				  struct snd_soc_dai *dai)
94 {
95 	struct rk_pdm_dev *pdm = to_info(dai);
96 	unsigned int val = 0;
97 	unsigned int clk_rate, clk_div, samplerate;
98 	int ret;
99 
100 	samplerate = params_rate(params);
101 	clk_rate = get_pdm_clk(samplerate);
102 	if (!clk_rate)
103 		return -EINVAL;
104 
105 	ret = clk_set_rate(pdm->clk, clk_rate);
106 	if (ret)
107 		return -EINVAL;
108 
109 	clk_div = DIV_ROUND_CLOSEST(clk_rate, samplerate);
110 
111 	switch (clk_div) {
112 	case 320:
113 		val = PDM_CLK_320FS;
114 		break;
115 	case 640:
116 		val = PDM_CLK_640FS;
117 		break;
118 	case 1280:
119 		val = PDM_CLK_1280FS;
120 		break;
121 	case 2560:
122 		val = PDM_CLK_2560FS;
123 		break;
124 	case 5120:
125 		val = PDM_CLK_5120FS;
126 		break;
127 	default:
128 		dev_err(pdm->dev, "unsupported div: %d\n", clk_div);
129 		return -EINVAL;
130 	}
131 
132 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_DS_RATIO_MSK, val);
133 	regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
134 			   PDM_HPF_CF_MSK, PDM_HPF_60HZ);
135 	regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
136 			   PDM_HPF_LE | PDM_HPF_RE, PDM_HPF_LE | PDM_HPF_RE);
137 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_CLK_EN, PDM_CLK_EN);
138 
139 	val = 0;
140 	switch (params_format(params)) {
141 	case SNDRV_PCM_FORMAT_S8:
142 		val |= PDM_VDW(8);
143 		break;
144 	case SNDRV_PCM_FORMAT_S16_LE:
145 		val |= PDM_VDW(16);
146 		break;
147 	case SNDRV_PCM_FORMAT_S20_3LE:
148 		val |= PDM_VDW(20);
149 		break;
150 	case SNDRV_PCM_FORMAT_S24_LE:
151 		val |= PDM_VDW(24);
152 		break;
153 	case SNDRV_PCM_FORMAT_S32_LE:
154 		val |= PDM_VDW(32);
155 		break;
156 	default:
157 		return -EINVAL;
158 	}
159 
160 	switch (params_channels(params)) {
161 	case 8:
162 		val |= PDM_PATH3_EN;
163 		/* fallthrough */
164 	case 6:
165 		val |= PDM_PATH2_EN;
166 		/* fallthrough */
167 	case 4:
168 		val |= PDM_PATH1_EN;
169 		/* fallthrough */
170 	case 2:
171 		val |= PDM_PATH0_EN;
172 		break;
173 	default:
174 		dev_err(pdm->dev, "invalid channel: %d\n",
175 			params_channels(params));
176 		return -EINVAL;
177 	}
178 
179 	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
180 		regmap_update_bits(pdm->regmap, PDM_CTRL0,
181 				   PDM_PATH_MSK | PDM_VDW_MSK,
182 				   val);
183 		regmap_update_bits(pdm->regmap, PDM_DMA_CTRL, PDM_DMA_RDL_MSK,
184 				   PDM_DMA_RDL(16));
185 		regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
186 				   PDM_RX_MASK | PDM_RX_CLR_MASK,
187 				   PDM_RX_STOP | PDM_RX_CLR_WR);
188 	}
189 
190 	return 0;
191 }
192 
193 static int rockchip_pdm_set_fmt(struct snd_soc_dai *cpu_dai,
194 				unsigned int fmt)
195 {
196 	struct rk_pdm_dev *pdm = to_info(cpu_dai);
197 	unsigned int mask = 0, val = 0;
198 
199 	mask = PDM_CKP_MSK;
200 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
201 	case SND_SOC_DAIFMT_NB_NF:
202 		val = PDM_CKP_NORMAL;
203 		break;
204 	case SND_SOC_DAIFMT_IB_NF:
205 		val = PDM_CKP_INVERTED;
206 		break;
207 	default:
208 		return -EINVAL;
209 	}
210 
211 	pm_runtime_get_sync(cpu_dai->dev);
212 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, mask, val);
213 	pm_runtime_put(cpu_dai->dev);
214 
215 	return 0;
216 }
217 
218 static int rockchip_pdm_trigger(struct snd_pcm_substream *substream, int cmd,
219 				struct snd_soc_dai *dai)
220 {
221 	struct rk_pdm_dev *pdm = to_info(dai);
222 	int ret = 0;
223 
224 	switch (cmd) {
225 	case SNDRV_PCM_TRIGGER_START:
226 	case SNDRV_PCM_TRIGGER_RESUME:
227 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
228 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
229 			rockchip_pdm_rxctrl(pdm, 1);
230 		break;
231 	case SNDRV_PCM_TRIGGER_SUSPEND:
232 	case SNDRV_PCM_TRIGGER_STOP:
233 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
234 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
235 			rockchip_pdm_rxctrl(pdm, 0);
236 		break;
237 	default:
238 		ret = -EINVAL;
239 		break;
240 	}
241 
242 	return ret;
243 }
244 
245 static int rockchip_pdm_dai_probe(struct snd_soc_dai *dai)
246 {
247 	struct rk_pdm_dev *pdm = to_info(dai);
248 
249 	dai->capture_dma_data = &pdm->capture_dma_data;
250 
251 	return 0;
252 }
253 
254 static const struct snd_soc_dai_ops rockchip_pdm_dai_ops = {
255 	.set_fmt = rockchip_pdm_set_fmt,
256 	.trigger = rockchip_pdm_trigger,
257 	.hw_params = rockchip_pdm_hw_params,
258 };
259 
260 #define ROCKCHIP_PDM_RATES SNDRV_PCM_RATE_8000_192000
261 #define ROCKCHIP_PDM_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
262 			      SNDRV_PCM_FMTBIT_S20_3LE | \
263 			      SNDRV_PCM_FMTBIT_S24_LE | \
264 			      SNDRV_PCM_FMTBIT_S32_LE)
265 
266 static struct snd_soc_dai_driver rockchip_pdm_dai = {
267 	.probe = rockchip_pdm_dai_probe,
268 	.capture = {
269 		.stream_name = "Capture",
270 		.channels_min = 2,
271 		.channels_max = 8,
272 		.rates = ROCKCHIP_PDM_RATES,
273 		.formats = ROCKCHIP_PDM_FORMATS,
274 	},
275 	.ops = &rockchip_pdm_dai_ops,
276 	.symmetric_rates = 1,
277 };
278 
279 static const struct snd_soc_component_driver rockchip_pdm_component = {
280 	.name = "rockchip-pdm",
281 };
282 
283 static int rockchip_pdm_runtime_suspend(struct device *dev)
284 {
285 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
286 
287 	clk_disable_unprepare(pdm->clk);
288 	clk_disable_unprepare(pdm->hclk);
289 
290 	return 0;
291 }
292 
293 static int rockchip_pdm_runtime_resume(struct device *dev)
294 {
295 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
296 	int ret;
297 
298 	ret = clk_prepare_enable(pdm->clk);
299 	if (ret) {
300 		dev_err(pdm->dev, "clock enable failed %d\n", ret);
301 		return ret;
302 	}
303 
304 	ret = clk_prepare_enable(pdm->hclk);
305 	if (ret) {
306 		dev_err(pdm->dev, "hclock enable failed %d\n", ret);
307 		return ret;
308 	}
309 
310 	return 0;
311 }
312 
313 static bool rockchip_pdm_wr_reg(struct device *dev, unsigned int reg)
314 {
315 	switch (reg) {
316 	case PDM_SYSCONFIG:
317 	case PDM_CTRL0:
318 	case PDM_CTRL1:
319 	case PDM_CLK_CTRL:
320 	case PDM_HPF_CTRL:
321 	case PDM_FIFO_CTRL:
322 	case PDM_DMA_CTRL:
323 	case PDM_INT_EN:
324 	case PDM_INT_CLR:
325 	case PDM_DATA_VALID:
326 		return true;
327 	default:
328 		return false;
329 	}
330 }
331 
332 static bool rockchip_pdm_rd_reg(struct device *dev, unsigned int reg)
333 {
334 	switch (reg) {
335 	case PDM_SYSCONFIG:
336 	case PDM_CTRL0:
337 	case PDM_CTRL1:
338 	case PDM_CLK_CTRL:
339 	case PDM_HPF_CTRL:
340 	case PDM_FIFO_CTRL:
341 	case PDM_DMA_CTRL:
342 	case PDM_INT_EN:
343 	case PDM_INT_CLR:
344 	case PDM_INT_ST:
345 	case PDM_DATA_VALID:
346 	case PDM_VERSION:
347 		return true;
348 	default:
349 		return false;
350 	}
351 }
352 
353 static bool rockchip_pdm_volatile_reg(struct device *dev, unsigned int reg)
354 {
355 	switch (reg) {
356 	case PDM_SYSCONFIG:
357 	case PDM_INT_CLR:
358 	case PDM_INT_ST:
359 		return true;
360 	default:
361 		return false;
362 	}
363 }
364 
365 static const struct regmap_config rockchip_pdm_regmap_config = {
366 	.reg_bits = 32,
367 	.reg_stride = 4,
368 	.val_bits = 32,
369 	.max_register = PDM_VERSION,
370 	.writeable_reg = rockchip_pdm_wr_reg,
371 	.readable_reg = rockchip_pdm_rd_reg,
372 	.volatile_reg = rockchip_pdm_volatile_reg,
373 	.cache_type = REGCACHE_FLAT,
374 };
375 
376 static int rockchip_pdm_probe(struct platform_device *pdev)
377 {
378 	struct rk_pdm_dev *pdm;
379 	struct resource *res;
380 	void __iomem *regs;
381 	int ret;
382 
383 	pdm = devm_kzalloc(&pdev->dev, sizeof(*pdm), GFP_KERNEL);
384 	if (!pdm)
385 		return -ENOMEM;
386 
387 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
388 	regs = devm_ioremap_resource(&pdev->dev, res);
389 	if (IS_ERR(regs))
390 		return PTR_ERR(regs);
391 
392 	pdm->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
393 					    &rockchip_pdm_regmap_config);
394 	if (IS_ERR(pdm->regmap))
395 		return PTR_ERR(pdm->regmap);
396 
397 	pdm->capture_dma_data.addr = res->start + PDM_RXFIFO_DATA;
398 	pdm->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
399 	pdm->capture_dma_data.maxburst = PDM_DMA_BURST_SIZE;
400 
401 	pdm->dev = &pdev->dev;
402 	dev_set_drvdata(&pdev->dev, pdm);
403 
404 	pdm->clk = devm_clk_get(&pdev->dev, "pdm_clk");
405 	if (IS_ERR(pdm->clk))
406 		return PTR_ERR(pdm->clk);
407 
408 	pdm->hclk = devm_clk_get(&pdev->dev, "pdm_hclk");
409 	if (IS_ERR(pdm->hclk))
410 		return PTR_ERR(pdm->hclk);
411 
412 	ret = clk_prepare_enable(pdm->hclk);
413 	if (ret)
414 		return ret;
415 
416 	pm_runtime_enable(&pdev->dev);
417 	if (!pm_runtime_enabled(&pdev->dev)) {
418 		ret = rockchip_pdm_runtime_resume(&pdev->dev);
419 		if (ret)
420 			goto err_pm_disable;
421 	}
422 
423 	ret = devm_snd_soc_register_component(&pdev->dev,
424 					      &rockchip_pdm_component,
425 					      &rockchip_pdm_dai, 1);
426 
427 	if (ret) {
428 		dev_err(&pdev->dev, "could not register dai: %d\n", ret);
429 		goto err_suspend;
430 	}
431 
432 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
433 	if (ret) {
434 		dev_err(&pdev->dev, "could not register pcm: %d\n", ret);
435 		goto err_suspend;
436 	}
437 
438 	return 0;
439 
440 err_suspend:
441 	if (!pm_runtime_status_suspended(&pdev->dev))
442 		rockchip_pdm_runtime_suspend(&pdev->dev);
443 err_pm_disable:
444 	pm_runtime_disable(&pdev->dev);
445 
446 	clk_disable_unprepare(pdm->hclk);
447 
448 	return ret;
449 }
450 
451 static int rockchip_pdm_remove(struct platform_device *pdev)
452 {
453 	struct rk_pdm_dev *pdm = dev_get_drvdata(&pdev->dev);
454 
455 	pm_runtime_disable(&pdev->dev);
456 	if (!pm_runtime_status_suspended(&pdev->dev))
457 		rockchip_pdm_runtime_suspend(&pdev->dev);
458 
459 	clk_disable_unprepare(pdm->clk);
460 	clk_disable_unprepare(pdm->hclk);
461 
462 	return 0;
463 }
464 
465 #ifdef CONFIG_PM_SLEEP
466 static int rockchip_pdm_suspend(struct device *dev)
467 {
468 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
469 
470 	regcache_mark_dirty(pdm->regmap);
471 
472 	return 0;
473 }
474 
475 static int rockchip_pdm_resume(struct device *dev)
476 {
477 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
478 	int ret;
479 
480 	ret = pm_runtime_get_sync(dev);
481 	if (ret < 0)
482 		return ret;
483 
484 	ret = regcache_sync(pdm->regmap);
485 
486 	pm_runtime_put(dev);
487 
488 	return ret;
489 }
490 #endif
491 
492 static const struct dev_pm_ops rockchip_pdm_pm_ops = {
493 	SET_RUNTIME_PM_OPS(rockchip_pdm_runtime_suspend,
494 			   rockchip_pdm_runtime_resume, NULL)
495 	SET_SYSTEM_SLEEP_PM_OPS(rockchip_pdm_suspend, rockchip_pdm_resume)
496 };
497 
498 static const struct of_device_id rockchip_pdm_match[] = {
499 	{ .compatible = "rockchip,pdm", },
500 	{},
501 };
502 MODULE_DEVICE_TABLE(of, rockchip_pdm_match);
503 
504 static struct platform_driver rockchip_pdm_driver = {
505 	.probe  = rockchip_pdm_probe,
506 	.remove = rockchip_pdm_remove,
507 	.driver = {
508 		.name = "rockchip-pdm",
509 		.of_match_table = of_match_ptr(rockchip_pdm_match),
510 		.pm = &rockchip_pdm_pm_ops,
511 	},
512 };
513 
514 module_platform_driver(rockchip_pdm_driver);
515 
516 MODULE_AUTHOR("Sugar <sugar.zhang@rock-chips.com>");
517 MODULE_DESCRIPTION("Rockchip PDM Controller Driver");
518 MODULE_LICENSE("GPL v2");
519