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	(16) /* size * width: 16*4 = 64 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 	regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, mask, val);
212 
213 	return 0;
214 }
215 
216 static int rockchip_pdm_trigger(struct snd_pcm_substream *substream, int cmd,
217 				struct snd_soc_dai *dai)
218 {
219 	struct rk_pdm_dev *pdm = to_info(dai);
220 	int ret = 0;
221 
222 	switch (cmd) {
223 	case SNDRV_PCM_TRIGGER_START:
224 	case SNDRV_PCM_TRIGGER_RESUME:
225 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
226 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
227 			rockchip_pdm_rxctrl(pdm, 1);
228 		break;
229 	case SNDRV_PCM_TRIGGER_SUSPEND:
230 	case SNDRV_PCM_TRIGGER_STOP:
231 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
232 		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
233 			rockchip_pdm_rxctrl(pdm, 0);
234 		break;
235 	default:
236 		ret = -EINVAL;
237 		break;
238 	}
239 
240 	return ret;
241 }
242 
243 static int rockchip_pdm_dai_probe(struct snd_soc_dai *dai)
244 {
245 	struct rk_pdm_dev *pdm = to_info(dai);
246 
247 	dai->capture_dma_data = &pdm->capture_dma_data;
248 
249 	return 0;
250 }
251 
252 static struct snd_soc_dai_ops rockchip_pdm_dai_ops = {
253 	.set_fmt = rockchip_pdm_set_fmt,
254 	.trigger = rockchip_pdm_trigger,
255 	.hw_params = rockchip_pdm_hw_params,
256 };
257 
258 #define ROCKCHIP_PDM_RATES SNDRV_PCM_RATE_8000_192000
259 #define ROCKCHIP_PDM_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
260 			      SNDRV_PCM_FMTBIT_S20_3LE | \
261 			      SNDRV_PCM_FMTBIT_S24_LE | \
262 			      SNDRV_PCM_FMTBIT_S32_LE)
263 
264 static struct snd_soc_dai_driver rockchip_pdm_dai = {
265 	.probe = rockchip_pdm_dai_probe,
266 	.capture = {
267 		.stream_name = "Capture",
268 		.channels_min = 2,
269 		.channels_max = 8,
270 		.rates = ROCKCHIP_PDM_RATES,
271 		.formats = ROCKCHIP_PDM_FORMATS,
272 	},
273 	.ops = &rockchip_pdm_dai_ops,
274 	.symmetric_rates = 1,
275 };
276 
277 static const struct snd_soc_component_driver rockchip_pdm_component = {
278 	.name = "rockchip-pdm",
279 };
280 
281 static int rockchip_pdm_runtime_suspend(struct device *dev)
282 {
283 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
284 
285 	clk_disable_unprepare(pdm->clk);
286 	clk_disable_unprepare(pdm->hclk);
287 
288 	return 0;
289 }
290 
291 static int rockchip_pdm_runtime_resume(struct device *dev)
292 {
293 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
294 	int ret;
295 
296 	ret = clk_prepare_enable(pdm->clk);
297 	if (ret) {
298 		dev_err(pdm->dev, "clock enable failed %d\n", ret);
299 		return ret;
300 	}
301 
302 	ret = clk_prepare_enable(pdm->hclk);
303 	if (ret) {
304 		dev_err(pdm->dev, "hclock enable failed %d\n", ret);
305 		return ret;
306 	}
307 
308 	return 0;
309 }
310 
311 static bool rockchip_pdm_wr_reg(struct device *dev, unsigned int reg)
312 {
313 	switch (reg) {
314 	case PDM_SYSCONFIG:
315 	case PDM_CTRL0:
316 	case PDM_CTRL1:
317 	case PDM_CLK_CTRL:
318 	case PDM_HPF_CTRL:
319 	case PDM_FIFO_CTRL:
320 	case PDM_DMA_CTRL:
321 	case PDM_INT_EN:
322 	case PDM_INT_CLR:
323 	case PDM_DATA_VALID:
324 		return true;
325 	default:
326 		return false;
327 	}
328 }
329 
330 static bool rockchip_pdm_rd_reg(struct device *dev, unsigned int reg)
331 {
332 	switch (reg) {
333 	case PDM_SYSCONFIG:
334 	case PDM_CTRL0:
335 	case PDM_CTRL1:
336 	case PDM_CLK_CTRL:
337 	case PDM_HPF_CTRL:
338 	case PDM_FIFO_CTRL:
339 	case PDM_DMA_CTRL:
340 	case PDM_INT_EN:
341 	case PDM_INT_CLR:
342 	case PDM_INT_ST:
343 	case PDM_DATA_VALID:
344 	case PDM_VERSION:
345 		return true;
346 	default:
347 		return false;
348 	}
349 }
350 
351 static bool rockchip_pdm_volatile_reg(struct device *dev, unsigned int reg)
352 {
353 	switch (reg) {
354 	case PDM_SYSCONFIG:
355 	case PDM_INT_CLR:
356 	case PDM_INT_ST:
357 		return true;
358 	default:
359 		return false;
360 	}
361 }
362 
363 static const struct regmap_config rockchip_pdm_regmap_config = {
364 	.reg_bits = 32,
365 	.reg_stride = 4,
366 	.val_bits = 32,
367 	.max_register = PDM_VERSION,
368 	.writeable_reg = rockchip_pdm_wr_reg,
369 	.readable_reg = rockchip_pdm_rd_reg,
370 	.volatile_reg = rockchip_pdm_volatile_reg,
371 	.cache_type = REGCACHE_FLAT,
372 };
373 
374 static int rockchip_pdm_probe(struct platform_device *pdev)
375 {
376 	struct rk_pdm_dev *pdm;
377 	struct resource *res;
378 	void __iomem *regs;
379 	int ret;
380 
381 	pdm = devm_kzalloc(&pdev->dev, sizeof(*pdm), GFP_KERNEL);
382 	if (!pdm)
383 		return -ENOMEM;
384 
385 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
386 	regs = devm_ioremap_resource(&pdev->dev, res);
387 	if (IS_ERR(regs))
388 		return PTR_ERR(regs);
389 
390 	pdm->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
391 					    &rockchip_pdm_regmap_config);
392 	if (IS_ERR(pdm->regmap))
393 		return PTR_ERR(pdm->regmap);
394 
395 	pdm->capture_dma_data.addr = res->start + PDM_RXFIFO_DATA;
396 	pdm->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
397 	pdm->capture_dma_data.maxburst = PDM_DMA_BURST_SIZE;
398 
399 	pdm->dev = &pdev->dev;
400 	dev_set_drvdata(&pdev->dev, pdm);
401 
402 	pdm->clk = devm_clk_get(&pdev->dev, "pdm_clk");
403 	if (IS_ERR(pdm->clk))
404 		return PTR_ERR(pdm->clk);
405 
406 	pdm->hclk = devm_clk_get(&pdev->dev, "pdm_hclk");
407 	if (IS_ERR(pdm->hclk))
408 		return PTR_ERR(pdm->hclk);
409 
410 	ret = clk_prepare_enable(pdm->hclk);
411 	if (ret)
412 		return ret;
413 
414 	pm_runtime_enable(&pdev->dev);
415 	if (!pm_runtime_enabled(&pdev->dev)) {
416 		ret = rockchip_pdm_runtime_resume(&pdev->dev);
417 		if (ret)
418 			goto err_pm_disable;
419 	}
420 
421 	ret = devm_snd_soc_register_component(&pdev->dev,
422 					      &rockchip_pdm_component,
423 					      &rockchip_pdm_dai, 1);
424 
425 	if (ret) {
426 		dev_err(&pdev->dev, "could not register dai: %d\n", ret);
427 		goto err_suspend;
428 	}
429 
430 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
431 	if (ret) {
432 		dev_err(&pdev->dev, "could not register pcm: %d\n", ret);
433 		goto err_suspend;
434 	}
435 
436 	return 0;
437 
438 err_suspend:
439 	if (!pm_runtime_status_suspended(&pdev->dev))
440 		rockchip_pdm_runtime_suspend(&pdev->dev);
441 err_pm_disable:
442 	pm_runtime_disable(&pdev->dev);
443 
444 	clk_disable_unprepare(pdm->hclk);
445 
446 	return ret;
447 }
448 
449 static int rockchip_pdm_remove(struct platform_device *pdev)
450 {
451 	struct rk_pdm_dev *pdm = dev_get_drvdata(&pdev->dev);
452 
453 	pm_runtime_disable(&pdev->dev);
454 	if (!pm_runtime_status_suspended(&pdev->dev))
455 		rockchip_pdm_runtime_suspend(&pdev->dev);
456 
457 	clk_disable_unprepare(pdm->clk);
458 	clk_disable_unprepare(pdm->hclk);
459 
460 	return 0;
461 }
462 
463 #ifdef CONFIG_PM_SLEEP
464 static int rockchip_pdm_suspend(struct device *dev)
465 {
466 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
467 
468 	regcache_mark_dirty(pdm->regmap);
469 
470 	return 0;
471 }
472 
473 static int rockchip_pdm_resume(struct device *dev)
474 {
475 	struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
476 	int ret;
477 
478 	ret = pm_runtime_get_sync(dev);
479 	if (ret < 0)
480 		return ret;
481 
482 	ret = regcache_sync(pdm->regmap);
483 
484 	pm_runtime_put(dev);
485 
486 	return ret;
487 }
488 #endif
489 
490 static const struct dev_pm_ops rockchip_pdm_pm_ops = {
491 	SET_RUNTIME_PM_OPS(rockchip_pdm_runtime_suspend,
492 			   rockchip_pdm_runtime_resume, NULL)
493 	SET_SYSTEM_SLEEP_PM_OPS(rockchip_pdm_suspend, rockchip_pdm_resume)
494 };
495 
496 static const struct of_device_id rockchip_pdm_match[] = {
497 	{ .compatible = "rockchip,pdm", },
498 	{},
499 };
500 MODULE_DEVICE_TABLE(of, rockchip_pdm_match);
501 
502 static struct platform_driver rockchip_pdm_driver = {
503 	.probe  = rockchip_pdm_probe,
504 	.remove = rockchip_pdm_remove,
505 	.driver = {
506 		.name = "rockchip-pdm",
507 		.of_match_table = of_match_ptr(rockchip_pdm_match),
508 		.pm = &rockchip_pdm_pm_ops,
509 	},
510 };
511 
512 module_platform_driver(rockchip_pdm_driver);
513 
514 MODULE_AUTHOR("Sugar <sugar.zhang@rock-chips.com>");
515 MODULE_DESCRIPTION("Rockchip PDM Controller Driver");
516 MODULE_LICENSE("GPL v2");
517