xref: /openbmc/linux/sound/soc/tegra/tegra20_i2s.c (revision 94d964e5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * tegra20_i2s.c - Tegra20 I2S driver
4  *
5  * Author: Stephen Warren <swarren@nvidia.com>
6  * Copyright (C) 2010,2012 - NVIDIA, Inc.
7  *
8  * Based on code copyright/by:
9  *
10  * Copyright (c) 2009-2010, NVIDIA Corporation.
11  * Scott Peterson <speterson@nvidia.com>
12  *
13  * Copyright (C) 2010 Google, Inc.
14  * Iliyan Malchev <malchev@google.com>
15  */
16 
17 #include <linux/clk.h>
18 #include <linux/device.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/regmap.h>
25 #include <linux/reset.h>
26 #include <linux/slab.h>
27 #include <sound/core.h>
28 #include <sound/pcm.h>
29 #include <sound/pcm_params.h>
30 #include <sound/soc.h>
31 #include <sound/dmaengine_pcm.h>
32 
33 #include "tegra20_i2s.h"
34 
35 #define DRV_NAME "tegra20-i2s"
36 
37 static __maybe_unused int tegra20_i2s_runtime_suspend(struct device *dev)
38 {
39 	struct tegra20_i2s *i2s = dev_get_drvdata(dev);
40 
41 	regcache_cache_only(i2s->regmap, true);
42 
43 	clk_disable_unprepare(i2s->clk_i2s);
44 
45 	return 0;
46 }
47 
48 static __maybe_unused int tegra20_i2s_runtime_resume(struct device *dev)
49 {
50 	struct tegra20_i2s *i2s = dev_get_drvdata(dev);
51 	int ret;
52 
53 	ret = reset_control_assert(i2s->reset);
54 	if (ret)
55 		return ret;
56 
57 	ret = clk_prepare_enable(i2s->clk_i2s);
58 	if (ret) {
59 		dev_err(dev, "clk_enable failed: %d\n", ret);
60 		return ret;
61 	}
62 
63 	usleep_range(10, 100);
64 
65 	ret = reset_control_deassert(i2s->reset);
66 	if (ret)
67 		goto disable_clocks;
68 
69 	regcache_cache_only(i2s->regmap, false);
70 	regcache_mark_dirty(i2s->regmap);
71 
72 	ret = regcache_sync(i2s->regmap);
73 	if (ret)
74 		goto disable_clocks;
75 
76 	return 0;
77 
78 disable_clocks:
79 	clk_disable_unprepare(i2s->clk_i2s);
80 
81 	return ret;
82 }
83 
84 static int tegra20_i2s_set_fmt(struct snd_soc_dai *dai,
85 				unsigned int fmt)
86 {
87 	struct tegra20_i2s *i2s = snd_soc_dai_get_drvdata(dai);
88 	unsigned int mask = 0, val = 0;
89 
90 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
91 	case SND_SOC_DAIFMT_NB_NF:
92 		break;
93 	default:
94 		return -EINVAL;
95 	}
96 
97 	mask |= TEGRA20_I2S_CTRL_MASTER_ENABLE;
98 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
99 	case SND_SOC_DAIFMT_CBS_CFS:
100 		val |= TEGRA20_I2S_CTRL_MASTER_ENABLE;
101 		break;
102 	case SND_SOC_DAIFMT_CBM_CFM:
103 		break;
104 	default:
105 		return -EINVAL;
106 	}
107 
108 	mask |= TEGRA20_I2S_CTRL_BIT_FORMAT_MASK |
109 		TEGRA20_I2S_CTRL_LRCK_MASK;
110 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
111 	case SND_SOC_DAIFMT_DSP_A:
112 		val |= TEGRA20_I2S_CTRL_BIT_FORMAT_DSP;
113 		val |= TEGRA20_I2S_CTRL_LRCK_L_LOW;
114 		break;
115 	case SND_SOC_DAIFMT_DSP_B:
116 		val |= TEGRA20_I2S_CTRL_BIT_FORMAT_DSP;
117 		val |= TEGRA20_I2S_CTRL_LRCK_R_LOW;
118 		break;
119 	case SND_SOC_DAIFMT_I2S:
120 		val |= TEGRA20_I2S_CTRL_BIT_FORMAT_I2S;
121 		val |= TEGRA20_I2S_CTRL_LRCK_L_LOW;
122 		break;
123 	case SND_SOC_DAIFMT_RIGHT_J:
124 		val |= TEGRA20_I2S_CTRL_BIT_FORMAT_RJM;
125 		val |= TEGRA20_I2S_CTRL_LRCK_L_LOW;
126 		break;
127 	case SND_SOC_DAIFMT_LEFT_J:
128 		val |= TEGRA20_I2S_CTRL_BIT_FORMAT_LJM;
129 		val |= TEGRA20_I2S_CTRL_LRCK_L_LOW;
130 		break;
131 	default:
132 		return -EINVAL;
133 	}
134 
135 	regmap_update_bits(i2s->regmap, TEGRA20_I2S_CTRL, mask, val);
136 
137 	return 0;
138 }
139 
140 static int tegra20_i2s_hw_params(struct snd_pcm_substream *substream,
141 				 struct snd_pcm_hw_params *params,
142 				 struct snd_soc_dai *dai)
143 {
144 	struct device *dev = dai->dev;
145 	struct tegra20_i2s *i2s = snd_soc_dai_get_drvdata(dai);
146 	unsigned int mask, val;
147 	int ret, sample_size, srate, i2sclock, bitcnt;
148 
149 	mask = TEGRA20_I2S_CTRL_BIT_SIZE_MASK;
150 	switch (params_format(params)) {
151 	case SNDRV_PCM_FORMAT_S16_LE:
152 		val = TEGRA20_I2S_CTRL_BIT_SIZE_16;
153 		sample_size = 16;
154 		break;
155 	case SNDRV_PCM_FORMAT_S24_LE:
156 		val = TEGRA20_I2S_CTRL_BIT_SIZE_24;
157 		sample_size = 24;
158 		break;
159 	case SNDRV_PCM_FORMAT_S32_LE:
160 		val = TEGRA20_I2S_CTRL_BIT_SIZE_32;
161 		sample_size = 32;
162 		break;
163 	default:
164 		return -EINVAL;
165 	}
166 
167 	mask |= TEGRA20_I2S_CTRL_FIFO_FORMAT_MASK;
168 	val |= TEGRA20_I2S_CTRL_FIFO_FORMAT_PACKED;
169 
170 	regmap_update_bits(i2s->regmap, TEGRA20_I2S_CTRL, mask, val);
171 
172 	srate = params_rate(params);
173 
174 	/* Final "* 2" required by Tegra hardware */
175 	i2sclock = srate * params_channels(params) * sample_size * 2;
176 
177 	ret = clk_set_rate(i2s->clk_i2s, i2sclock);
178 	if (ret) {
179 		dev_err(dev, "Can't set I2S clock rate: %d\n", ret);
180 		return ret;
181 	}
182 
183 	bitcnt = (i2sclock / (2 * srate)) - 1;
184 	if (bitcnt < 0 || bitcnt > TEGRA20_I2S_TIMING_CHANNEL_BIT_COUNT_MASK_US)
185 		return -EINVAL;
186 	val = bitcnt << TEGRA20_I2S_TIMING_CHANNEL_BIT_COUNT_SHIFT;
187 
188 	if (i2sclock % (2 * srate))
189 		val |= TEGRA20_I2S_TIMING_NON_SYM_ENABLE;
190 
191 	regmap_write(i2s->regmap, TEGRA20_I2S_TIMING, val);
192 
193 	regmap_write(i2s->regmap, TEGRA20_I2S_FIFO_SCR,
194 		     TEGRA20_I2S_FIFO_SCR_FIFO2_ATN_LVL_FOUR_SLOTS |
195 		     TEGRA20_I2S_FIFO_SCR_FIFO1_ATN_LVL_FOUR_SLOTS);
196 
197 	return 0;
198 }
199 
200 static void tegra20_i2s_start_playback(struct tegra20_i2s *i2s)
201 {
202 	regmap_update_bits(i2s->regmap, TEGRA20_I2S_CTRL,
203 			   TEGRA20_I2S_CTRL_FIFO1_ENABLE,
204 			   TEGRA20_I2S_CTRL_FIFO1_ENABLE);
205 }
206 
207 static void tegra20_i2s_stop_playback(struct tegra20_i2s *i2s)
208 {
209 	regmap_update_bits(i2s->regmap, TEGRA20_I2S_CTRL,
210 			   TEGRA20_I2S_CTRL_FIFO1_ENABLE, 0);
211 }
212 
213 static void tegra20_i2s_start_capture(struct tegra20_i2s *i2s)
214 {
215 	regmap_update_bits(i2s->regmap, TEGRA20_I2S_CTRL,
216 			   TEGRA20_I2S_CTRL_FIFO2_ENABLE,
217 			   TEGRA20_I2S_CTRL_FIFO2_ENABLE);
218 }
219 
220 static void tegra20_i2s_stop_capture(struct tegra20_i2s *i2s)
221 {
222 	regmap_update_bits(i2s->regmap, TEGRA20_I2S_CTRL,
223 			   TEGRA20_I2S_CTRL_FIFO2_ENABLE, 0);
224 }
225 
226 static int tegra20_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
227 			       struct snd_soc_dai *dai)
228 {
229 	struct tegra20_i2s *i2s = snd_soc_dai_get_drvdata(dai);
230 
231 	switch (cmd) {
232 	case SNDRV_PCM_TRIGGER_START:
233 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
234 	case SNDRV_PCM_TRIGGER_RESUME:
235 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
236 			tegra20_i2s_start_playback(i2s);
237 		else
238 			tegra20_i2s_start_capture(i2s);
239 		break;
240 	case SNDRV_PCM_TRIGGER_STOP:
241 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
242 	case SNDRV_PCM_TRIGGER_SUSPEND:
243 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
244 			tegra20_i2s_stop_playback(i2s);
245 		else
246 			tegra20_i2s_stop_capture(i2s);
247 		break;
248 	default:
249 		return -EINVAL;
250 	}
251 
252 	return 0;
253 }
254 
255 static int tegra20_i2s_probe(struct snd_soc_dai *dai)
256 {
257 	struct tegra20_i2s *i2s = snd_soc_dai_get_drvdata(dai);
258 
259 	dai->capture_dma_data = &i2s->capture_dma_data;
260 	dai->playback_dma_data = &i2s->playback_dma_data;
261 
262 	return 0;
263 }
264 
265 static const unsigned int tegra20_i2s_rates[] = {
266 	8000, 11025, 16000, 22050, 32000, 44100, 48000, 64000, 88200, 96000
267 };
268 
269 static int tegra20_i2s_filter_rates(struct snd_pcm_hw_params *params,
270 				    struct snd_pcm_hw_rule *rule)
271 {
272 	struct snd_interval *r = hw_param_interval(params, rule->var);
273 	struct snd_soc_dai *dai = rule->private;
274 	struct tegra20_i2s *i2s = dev_get_drvdata(dai->dev);
275 	struct clk *parent = clk_get_parent(i2s->clk_i2s);
276 	long i, parent_rate, valid_rates = 0;
277 
278 	parent_rate = clk_get_rate(parent);
279 	if (parent_rate <= 0) {
280 		dev_err(dai->dev, "Can't get parent clock rate: %ld\n",
281 			parent_rate);
282 		return parent_rate ?: -EINVAL;
283 	}
284 
285 	for (i = 0; i < ARRAY_SIZE(tegra20_i2s_rates); i++) {
286 		if (parent_rate % (tegra20_i2s_rates[i] * 128) == 0)
287 			valid_rates |= BIT(i);
288 	}
289 
290 	/*
291 	 * At least one rate must be valid, otherwise the parent clock isn't
292 	 * audio PLL. Nothing should be filtered in this case.
293 	 */
294 	if (!valid_rates)
295 		valid_rates = BIT(ARRAY_SIZE(tegra20_i2s_rates)) - 1;
296 
297 	return snd_interval_list(r, ARRAY_SIZE(tegra20_i2s_rates),
298 				 tegra20_i2s_rates, valid_rates);
299 }
300 
301 static int tegra20_i2s_startup(struct snd_pcm_substream *substream,
302 			       struct snd_soc_dai *dai)
303 {
304 	if (!device_property_read_bool(dai->dev, "nvidia,fixed-parent-rate"))
305 		return 0;
306 
307 	return snd_pcm_hw_rule_add(substream->runtime, 0,
308 				   SNDRV_PCM_HW_PARAM_RATE,
309 				   tegra20_i2s_filter_rates, dai,
310 				   SNDRV_PCM_HW_PARAM_RATE, -1);
311 }
312 
313 static const struct snd_soc_dai_ops tegra20_i2s_dai_ops = {
314 	.set_fmt	= tegra20_i2s_set_fmt,
315 	.hw_params	= tegra20_i2s_hw_params,
316 	.trigger	= tegra20_i2s_trigger,
317 	.startup	= tegra20_i2s_startup,
318 };
319 
320 static const struct snd_soc_dai_driver tegra20_i2s_dai_template = {
321 	.probe = tegra20_i2s_probe,
322 	.playback = {
323 		.stream_name = "Playback",
324 		.channels_min = 2,
325 		.channels_max = 2,
326 		.rates = SNDRV_PCM_RATE_8000_96000,
327 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
328 	},
329 	.capture = {
330 		.stream_name = "Capture",
331 		.channels_min = 2,
332 		.channels_max = 2,
333 		.rates = SNDRV_PCM_RATE_8000_96000,
334 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
335 	},
336 	.ops = &tegra20_i2s_dai_ops,
337 	.symmetric_rate = 1,
338 };
339 
340 static const struct snd_soc_component_driver tegra20_i2s_component = {
341 	.name		= DRV_NAME,
342 };
343 
344 static bool tegra20_i2s_wr_rd_reg(struct device *dev, unsigned int reg)
345 {
346 	switch (reg) {
347 	case TEGRA20_I2S_CTRL:
348 	case TEGRA20_I2S_STATUS:
349 	case TEGRA20_I2S_TIMING:
350 	case TEGRA20_I2S_FIFO_SCR:
351 	case TEGRA20_I2S_PCM_CTRL:
352 	case TEGRA20_I2S_NW_CTRL:
353 	case TEGRA20_I2S_TDM_CTRL:
354 	case TEGRA20_I2S_TDM_TX_RX_CTRL:
355 	case TEGRA20_I2S_FIFO1:
356 	case TEGRA20_I2S_FIFO2:
357 		return true;
358 	default:
359 		return false;
360 	}
361 }
362 
363 static bool tegra20_i2s_volatile_reg(struct device *dev, unsigned int reg)
364 {
365 	switch (reg) {
366 	case TEGRA20_I2S_STATUS:
367 	case TEGRA20_I2S_FIFO_SCR:
368 	case TEGRA20_I2S_FIFO1:
369 	case TEGRA20_I2S_FIFO2:
370 		return true;
371 	default:
372 		return false;
373 	}
374 }
375 
376 static bool tegra20_i2s_precious_reg(struct device *dev, unsigned int reg)
377 {
378 	switch (reg) {
379 	case TEGRA20_I2S_FIFO1:
380 	case TEGRA20_I2S_FIFO2:
381 		return true;
382 	default:
383 		return false;
384 	}
385 }
386 
387 static const struct regmap_config tegra20_i2s_regmap_config = {
388 	.reg_bits = 32,
389 	.reg_stride = 4,
390 	.val_bits = 32,
391 	.max_register = TEGRA20_I2S_FIFO2,
392 	.writeable_reg = tegra20_i2s_wr_rd_reg,
393 	.readable_reg = tegra20_i2s_wr_rd_reg,
394 	.volatile_reg = tegra20_i2s_volatile_reg,
395 	.precious_reg = tegra20_i2s_precious_reg,
396 	.cache_type = REGCACHE_FLAT,
397 };
398 
399 static int tegra20_i2s_platform_probe(struct platform_device *pdev)
400 {
401 	struct tegra20_i2s *i2s;
402 	struct resource *mem;
403 	void __iomem *regs;
404 	int ret;
405 
406 	i2s = devm_kzalloc(&pdev->dev, sizeof(struct tegra20_i2s), GFP_KERNEL);
407 	if (!i2s) {
408 		ret = -ENOMEM;
409 		goto err;
410 	}
411 	dev_set_drvdata(&pdev->dev, i2s);
412 
413 	i2s->dai = tegra20_i2s_dai_template;
414 	i2s->dai.name = dev_name(&pdev->dev);
415 
416 	i2s->reset = devm_reset_control_get_exclusive(&pdev->dev, "i2s");
417 	if (IS_ERR(i2s->reset)) {
418 		dev_err(&pdev->dev, "Can't retrieve i2s reset\n");
419 		return PTR_ERR(i2s->reset);
420 	}
421 
422 	i2s->clk_i2s = devm_clk_get(&pdev->dev, NULL);
423 	if (IS_ERR(i2s->clk_i2s)) {
424 		dev_err(&pdev->dev, "Can't retrieve i2s clock\n");
425 		ret = PTR_ERR(i2s->clk_i2s);
426 		goto err;
427 	}
428 
429 	regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
430 	if (IS_ERR(regs)) {
431 		ret = PTR_ERR(regs);
432 		goto err;
433 	}
434 
435 	i2s->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
436 					    &tegra20_i2s_regmap_config);
437 	if (IS_ERR(i2s->regmap)) {
438 		dev_err(&pdev->dev, "regmap init failed\n");
439 		ret = PTR_ERR(i2s->regmap);
440 		goto err;
441 	}
442 
443 	i2s->capture_dma_data.addr = mem->start + TEGRA20_I2S_FIFO2;
444 	i2s->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
445 	i2s->capture_dma_data.maxburst = 4;
446 
447 	i2s->playback_dma_data.addr = mem->start + TEGRA20_I2S_FIFO1;
448 	i2s->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
449 	i2s->playback_dma_data.maxburst = 4;
450 
451 	pm_runtime_enable(&pdev->dev);
452 
453 	ret = snd_soc_register_component(&pdev->dev, &tegra20_i2s_component,
454 					 &i2s->dai, 1);
455 	if (ret) {
456 		dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
457 		ret = -ENOMEM;
458 		goto err_pm_disable;
459 	}
460 
461 	ret = tegra_pcm_platform_register(&pdev->dev);
462 	if (ret) {
463 		dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
464 		goto err_unregister_component;
465 	}
466 
467 	return 0;
468 
469 err_unregister_component:
470 	snd_soc_unregister_component(&pdev->dev);
471 err_pm_disable:
472 	pm_runtime_disable(&pdev->dev);
473 err:
474 	return ret;
475 }
476 
477 static int tegra20_i2s_platform_remove(struct platform_device *pdev)
478 {
479 	tegra_pcm_platform_unregister(&pdev->dev);
480 	snd_soc_unregister_component(&pdev->dev);
481 	pm_runtime_disable(&pdev->dev);
482 
483 	return 0;
484 }
485 
486 static const struct of_device_id tegra20_i2s_of_match[] = {
487 	{ .compatible = "nvidia,tegra20-i2s", },
488 	{},
489 };
490 
491 static const struct dev_pm_ops tegra20_i2s_pm_ops = {
492 	SET_RUNTIME_PM_OPS(tegra20_i2s_runtime_suspend,
493 			   tegra20_i2s_runtime_resume, NULL)
494 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
495 				pm_runtime_force_resume)
496 };
497 
498 static struct platform_driver tegra20_i2s_driver = {
499 	.driver = {
500 		.name = DRV_NAME,
501 		.of_match_table = tegra20_i2s_of_match,
502 		.pm = &tegra20_i2s_pm_ops,
503 	},
504 	.probe = tegra20_i2s_platform_probe,
505 	.remove = tegra20_i2s_platform_remove,
506 };
507 module_platform_driver(tegra20_i2s_driver);
508 
509 MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
510 MODULE_DESCRIPTION("Tegra20 I2S ASoC driver");
511 MODULE_LICENSE("GPL");
512 MODULE_ALIAS("platform:" DRV_NAME);
513 MODULE_DEVICE_TABLE(of, tegra20_i2s_of_match);
514