xref: /linux/sound/soc/meson/axg-tdm-interface.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
1 // SPDX-License-Identifier: (GPL-2.0 OR MIT)
2 //
3 // Copyright (c) 2018 BayLibre, SAS.
4 // Author: Jerome Brunet <jbrunet@baylibre.com>
5 
6 #include <linux/clk.h>
7 #include <linux/module.h>
8 #include <linux/of_platform.h>
9 #include <sound/pcm_params.h>
10 #include <sound/soc.h>
11 #include <sound/soc-dai.h>
12 
13 #include "axg-tdm.h"
14 
15 enum {
16 	TDM_IFACE_PAD,
17 	TDM_IFACE_LOOPBACK,
18 };
19 
20 static unsigned int axg_tdm_slots_total(u32 *mask)
21 {
22 	unsigned int slots = 0;
23 	int i;
24 
25 	if (!mask)
26 		return 0;
27 
28 	/* Count the total number of slots provided by all 4 lanes */
29 	for (i = 0; i < AXG_TDM_NUM_LANES; i++)
30 		slots += hweight32(mask[i]);
31 
32 	return slots;
33 }
34 
35 int axg_tdm_set_tdm_slots(struct snd_soc_dai *dai, u32 *tx_mask,
36 			  u32 *rx_mask, unsigned int slots,
37 			  unsigned int slot_width)
38 {
39 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
40 	struct axg_tdm_stream *tx = (struct axg_tdm_stream *)
41 		dai->playback_dma_data;
42 	struct axg_tdm_stream *rx = (struct axg_tdm_stream *)
43 		dai->capture_dma_data;
44 	unsigned int tx_slots, rx_slots;
45 
46 	tx_slots = axg_tdm_slots_total(tx_mask);
47 	rx_slots = axg_tdm_slots_total(rx_mask);
48 
49 	/* We should at least have a slot for a valid interface */
50 	if (!tx_slots && !rx_slots) {
51 		dev_err(dai->dev, "interface has no slot\n");
52 		return -EINVAL;
53 	}
54 
55 	/*
56 	 * Amend the dai driver channel number and let dpcm channel merge do
57 	 * its job
58 	 */
59 	if (tx) {
60 		tx->mask = tx_mask;
61 		dai->driver->playback.channels_max = tx_slots;
62 	}
63 
64 	if (rx) {
65 		rx->mask = rx_mask;
66 		dai->driver->capture.channels_max = rx_slots;
67 	}
68 
69 	iface->slots = slots;
70 
71 	switch (slot_width) {
72 	case 0:
73 		/* defaults width to 32 if not provided */
74 		iface->slot_width = 32;
75 		break;
76 	case 8:
77 	case 16:
78 	case 24:
79 	case 32:
80 		iface->slot_width = slot_width;
81 		break;
82 	default:
83 		dev_err(dai->dev, "unsupported slot width: %d\n", slot_width);
84 		return -EINVAL;
85 	}
86 
87 	return 0;
88 }
89 EXPORT_SYMBOL_GPL(axg_tdm_set_tdm_slots);
90 
91 static int axg_tdm_iface_set_sysclk(struct snd_soc_dai *dai, int clk_id,
92 				    unsigned int freq, int dir)
93 {
94 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
95 	int ret = -ENOTSUPP;
96 
97 	if (dir == SND_SOC_CLOCK_OUT && clk_id == 0) {
98 		if (!iface->mclk) {
99 			dev_warn(dai->dev, "master clock not provided\n");
100 		} else {
101 			ret = clk_set_rate(iface->mclk, freq);
102 			if (!ret)
103 				iface->mclk_rate = freq;
104 		}
105 	}
106 
107 	return ret;
108 }
109 
110 static int axg_tdm_iface_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
111 {
112 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
113 
114 	/* These modes are not supported */
115 	if (fmt & (SND_SOC_DAIFMT_CBS_CFM | SND_SOC_DAIFMT_CBM_CFS)) {
116 		dev_err(dai->dev, "only CBS_CFS and CBM_CFM are supported\n");
117 		return -EINVAL;
118 	}
119 
120 	/* If the TDM interface is the clock master, it requires mclk */
121 	if (!iface->mclk && (fmt & SND_SOC_DAIFMT_CBS_CFS)) {
122 		dev_err(dai->dev, "cpu clock master: mclk missing\n");
123 		return -ENODEV;
124 	}
125 
126 	iface->fmt = fmt;
127 	return 0;
128 }
129 
130 static int axg_tdm_iface_startup(struct snd_pcm_substream *substream,
131 				 struct snd_soc_dai *dai)
132 {
133 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
134 	struct axg_tdm_stream *ts =
135 		snd_soc_dai_get_dma_data(dai, substream);
136 	int ret;
137 
138 	if (!axg_tdm_slots_total(ts->mask)) {
139 		dev_err(dai->dev, "interface has not slots\n");
140 		return -EINVAL;
141 	}
142 
143 	/* Apply component wide rate symmetry */
144 	if (dai->component->active) {
145 		ret = snd_pcm_hw_constraint_single(substream->runtime,
146 						   SNDRV_PCM_HW_PARAM_RATE,
147 						   iface->rate);
148 		if (ret < 0) {
149 			dev_err(dai->dev,
150 				"can't set iface rate constraint\n");
151 			return ret;
152 		}
153 	}
154 
155 	return 0;
156 }
157 
158 static int axg_tdm_iface_set_stream(struct snd_pcm_substream *substream,
159 				    struct snd_pcm_hw_params *params,
160 				    struct snd_soc_dai *dai)
161 {
162 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
163 	struct axg_tdm_stream *ts = snd_soc_dai_get_dma_data(dai, substream);
164 	unsigned int channels = params_channels(params);
165 	unsigned int width = params_width(params);
166 
167 	/* Save rate and sample_bits for component symmetry */
168 	iface->rate = params_rate(params);
169 
170 	/* Make sure this interface can cope with the stream */
171 	if (axg_tdm_slots_total(ts->mask) < channels) {
172 		dev_err(dai->dev, "not enough slots for channels\n");
173 		return -EINVAL;
174 	}
175 
176 	if (iface->slot_width < width) {
177 		dev_err(dai->dev, "incompatible slots width for stream\n");
178 		return -EINVAL;
179 	}
180 
181 	/* Save the parameter for tdmout/tdmin widgets */
182 	ts->physical_width = params_physical_width(params);
183 	ts->width = params_width(params);
184 	ts->channels = params_channels(params);
185 
186 	return 0;
187 }
188 
189 static int axg_tdm_iface_set_lrclk(struct snd_soc_dai *dai,
190 				   struct snd_pcm_hw_params *params)
191 {
192 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
193 	unsigned int ratio_num;
194 	int ret;
195 
196 	ret = clk_set_rate(iface->lrclk, params_rate(params));
197 	if (ret) {
198 		dev_err(dai->dev, "setting sample clock failed: %d\n", ret);
199 		return ret;
200 	}
201 
202 	switch (iface->fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
203 	case SND_SOC_DAIFMT_I2S:
204 	case SND_SOC_DAIFMT_LEFT_J:
205 	case SND_SOC_DAIFMT_RIGHT_J:
206 		/* 50% duty cycle ratio */
207 		ratio_num = 1;
208 		break;
209 
210 	case SND_SOC_DAIFMT_DSP_A:
211 	case SND_SOC_DAIFMT_DSP_B:
212 		/*
213 		 * A zero duty cycle ratio will result in setting the mininum
214 		 * ratio possible which, for this clock, is 1 cycle of the
215 		 * parent bclk clock high and the rest low, This is exactly
216 		 * what we want here.
217 		 */
218 		ratio_num = 0;
219 		break;
220 
221 	default:
222 		return -EINVAL;
223 	}
224 
225 	ret = clk_set_duty_cycle(iface->lrclk, ratio_num, 2);
226 	if (ret) {
227 		dev_err(dai->dev,
228 			"setting sample clock duty cycle failed: %d\n", ret);
229 		return ret;
230 	}
231 
232 	/* Set sample clock inversion */
233 	ret = clk_set_phase(iface->lrclk,
234 			    axg_tdm_lrclk_invert(iface->fmt) ? 180 : 0);
235 	if (ret) {
236 		dev_err(dai->dev,
237 			"setting sample clock phase failed: %d\n", ret);
238 		return ret;
239 	}
240 
241 	return 0;
242 }
243 
244 static int axg_tdm_iface_set_sclk(struct snd_soc_dai *dai,
245 				  struct snd_pcm_hw_params *params)
246 {
247 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
248 	unsigned long srate;
249 	int ret;
250 
251 	srate = iface->slots * iface->slot_width * params_rate(params);
252 
253 	if (!iface->mclk_rate) {
254 		/* If no specific mclk is requested, default to bit clock * 4 */
255 		clk_set_rate(iface->mclk, 4 * srate);
256 	} else {
257 		/* Check if we can actually get the bit clock from mclk */
258 		if (iface->mclk_rate % srate) {
259 			dev_err(dai->dev,
260 				"can't derive sclk %lu from mclk %lu\n",
261 				srate, iface->mclk_rate);
262 			return -EINVAL;
263 		}
264 	}
265 
266 	ret = clk_set_rate(iface->sclk, srate);
267 	if (ret) {
268 		dev_err(dai->dev, "setting bit clock failed: %d\n", ret);
269 		return ret;
270 	}
271 
272 	/* Set the bit clock inversion */
273 	ret = clk_set_phase(iface->sclk,
274 			    axg_tdm_sclk_invert(iface->fmt) ? 0 : 180);
275 	if (ret) {
276 		dev_err(dai->dev, "setting bit clock phase failed: %d\n", ret);
277 		return ret;
278 	}
279 
280 	return ret;
281 }
282 
283 static int axg_tdm_iface_hw_params(struct snd_pcm_substream *substream,
284 				   struct snd_pcm_hw_params *params,
285 				   struct snd_soc_dai *dai)
286 {
287 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
288 	int ret;
289 
290 	switch (iface->fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
291 	case SND_SOC_DAIFMT_I2S:
292 	case SND_SOC_DAIFMT_LEFT_J:
293 	case SND_SOC_DAIFMT_RIGHT_J:
294 		if (iface->slots > 2) {
295 			dev_err(dai->dev, "bad slot number for format: %d\n",
296 				iface->slots);
297 			return -EINVAL;
298 		}
299 		break;
300 
301 	case SND_SOC_DAI_FORMAT_DSP_A:
302 	case SND_SOC_DAI_FORMAT_DSP_B:
303 		break;
304 
305 	default:
306 		dev_err(dai->dev, "unsupported dai format\n");
307 		return -EINVAL;
308 	}
309 
310 	ret = axg_tdm_iface_set_stream(substream, params, dai);
311 	if (ret)
312 		return ret;
313 
314 	if (iface->fmt & SND_SOC_DAIFMT_CBS_CFS) {
315 		ret = axg_tdm_iface_set_sclk(dai, params);
316 		if (ret)
317 			return ret;
318 
319 		ret = axg_tdm_iface_set_lrclk(dai, params);
320 		if (ret)
321 			return ret;
322 	}
323 
324 	return 0;
325 }
326 
327 static int axg_tdm_iface_hw_free(struct snd_pcm_substream *substream,
328 				 struct snd_soc_dai *dai)
329 {
330 	struct axg_tdm_stream *ts = snd_soc_dai_get_dma_data(dai, substream);
331 
332 	/* Stop all attached formatters */
333 	axg_tdm_stream_stop(ts);
334 
335 	return 0;
336 }
337 
338 static int axg_tdm_iface_prepare(struct snd_pcm_substream *substream,
339 				 struct snd_soc_dai *dai)
340 {
341 	struct axg_tdm_stream *ts = snd_soc_dai_get_dma_data(dai, substream);
342 
343 	/* Force all attached formatters to update */
344 	return axg_tdm_stream_reset(ts);
345 }
346 
347 static int axg_tdm_iface_remove_dai(struct snd_soc_dai *dai)
348 {
349 	if (dai->capture_dma_data)
350 		axg_tdm_stream_free(dai->capture_dma_data);
351 
352 	if (dai->playback_dma_data)
353 		axg_tdm_stream_free(dai->playback_dma_data);
354 
355 	return 0;
356 }
357 
358 static int axg_tdm_iface_probe_dai(struct snd_soc_dai *dai)
359 {
360 	struct axg_tdm_iface *iface = snd_soc_dai_get_drvdata(dai);
361 
362 	if (dai->capture_widget) {
363 		dai->capture_dma_data = axg_tdm_stream_alloc(iface);
364 		if (!dai->capture_dma_data)
365 			return -ENOMEM;
366 	}
367 
368 	if (dai->playback_widget) {
369 		dai->playback_dma_data = axg_tdm_stream_alloc(iface);
370 		if (!dai->playback_dma_data) {
371 			axg_tdm_iface_remove_dai(dai);
372 			return -ENOMEM;
373 		}
374 	}
375 
376 	return 0;
377 }
378 
379 static const struct snd_soc_dai_ops axg_tdm_iface_ops = {
380 	.set_sysclk	= axg_tdm_iface_set_sysclk,
381 	.set_fmt	= axg_tdm_iface_set_fmt,
382 	.startup	= axg_tdm_iface_startup,
383 	.hw_params	= axg_tdm_iface_hw_params,
384 	.prepare	= axg_tdm_iface_prepare,
385 	.hw_free	= axg_tdm_iface_hw_free,
386 };
387 
388 /* TDM Backend DAIs */
389 static const struct snd_soc_dai_driver axg_tdm_iface_dai_drv[] = {
390 	[TDM_IFACE_PAD] = {
391 		.name = "TDM Pad",
392 		.playback = {
393 			.stream_name	= "Playback",
394 			.channels_min	= 1,
395 			.channels_max	= AXG_TDM_CHANNEL_MAX,
396 			.rates		= AXG_TDM_RATES,
397 			.formats	= AXG_TDM_FORMATS,
398 		},
399 		.capture = {
400 			.stream_name	= "Capture",
401 			.channels_min	= 1,
402 			.channels_max	= AXG_TDM_CHANNEL_MAX,
403 			.rates		= AXG_TDM_RATES,
404 			.formats	= AXG_TDM_FORMATS,
405 		},
406 		.id = TDM_IFACE_PAD,
407 		.ops = &axg_tdm_iface_ops,
408 		.probe = axg_tdm_iface_probe_dai,
409 		.remove = axg_tdm_iface_remove_dai,
410 	},
411 	[TDM_IFACE_LOOPBACK] = {
412 		.name = "TDM Loopback",
413 		.capture = {
414 			.stream_name	= "Loopback",
415 			.channels_min	= 1,
416 			.channels_max	= AXG_TDM_CHANNEL_MAX,
417 			.rates		= AXG_TDM_RATES,
418 			.formats	= AXG_TDM_FORMATS,
419 		},
420 		.id = TDM_IFACE_LOOPBACK,
421 		.ops = &axg_tdm_iface_ops,
422 		.probe = axg_tdm_iface_probe_dai,
423 		.remove = axg_tdm_iface_remove_dai,
424 	},
425 };
426 
427 static int axg_tdm_iface_set_bias_level(struct snd_soc_component *component,
428 					enum snd_soc_bias_level level)
429 {
430 	struct axg_tdm_iface *iface = snd_soc_component_get_drvdata(component);
431 	enum snd_soc_bias_level now =
432 		snd_soc_component_get_bias_level(component);
433 	int ret = 0;
434 
435 	switch (level) {
436 	case SND_SOC_BIAS_PREPARE:
437 		if (now == SND_SOC_BIAS_STANDBY)
438 			ret = clk_prepare_enable(iface->mclk);
439 		break;
440 
441 	case SND_SOC_BIAS_STANDBY:
442 		if (now == SND_SOC_BIAS_PREPARE)
443 			clk_disable_unprepare(iface->mclk);
444 		break;
445 
446 	case SND_SOC_BIAS_OFF:
447 	case SND_SOC_BIAS_ON:
448 		break;
449 	}
450 
451 	return ret;
452 }
453 
454 static const struct snd_soc_component_driver axg_tdm_iface_component_drv = {
455 	.set_bias_level	= axg_tdm_iface_set_bias_level,
456 };
457 
458 static const struct of_device_id axg_tdm_iface_of_match[] = {
459 	{ .compatible = "amlogic,axg-tdm-iface", },
460 	{}
461 };
462 MODULE_DEVICE_TABLE(of, axg_tdm_iface_of_match);
463 
464 static int axg_tdm_iface_probe(struct platform_device *pdev)
465 {
466 	struct device *dev = &pdev->dev;
467 	struct snd_soc_dai_driver *dai_drv;
468 	struct axg_tdm_iface *iface;
469 	int ret, i;
470 
471 	iface = devm_kzalloc(dev, sizeof(*iface), GFP_KERNEL);
472 	if (!iface)
473 		return -ENOMEM;
474 	platform_set_drvdata(pdev, iface);
475 
476 	/*
477 	 * Duplicate dai driver: depending on the slot masks configuration
478 	 * We'll change the number of channel provided by DAI stream, so dpcm
479 	 * channel merge can be done properly
480 	 */
481 	dai_drv = devm_kcalloc(dev, ARRAY_SIZE(axg_tdm_iface_dai_drv),
482 			       sizeof(*dai_drv), GFP_KERNEL);
483 	if (!dai_drv)
484 		return -ENOMEM;
485 
486 	for (i = 0; i < ARRAY_SIZE(axg_tdm_iface_dai_drv); i++)
487 		memcpy(&dai_drv[i], &axg_tdm_iface_dai_drv[i],
488 		       sizeof(*dai_drv));
489 
490 	/* Bit clock provided on the pad */
491 	iface->sclk = devm_clk_get(dev, "sclk");
492 	if (IS_ERR(iface->sclk)) {
493 		ret = PTR_ERR(iface->sclk);
494 		if (ret != -EPROBE_DEFER)
495 			dev_err(dev, "failed to get sclk: %d\n", ret);
496 		return ret;
497 	}
498 
499 	/* Sample clock provided on the pad */
500 	iface->lrclk = devm_clk_get(dev, "lrclk");
501 	if (IS_ERR(iface->lrclk)) {
502 		ret = PTR_ERR(iface->lrclk);
503 		if (ret != -EPROBE_DEFER)
504 			dev_err(dev, "failed to get lrclk: %d\n", ret);
505 		return ret;
506 	}
507 
508 	/*
509 	 * mclk maybe be missing when the cpu dai is in slave mode and
510 	 * the codec does not require it to provide a master clock.
511 	 * At this point, ignore the error if mclk is missing. We'll
512 	 * throw an error if the cpu dai is master and mclk is missing
513 	 */
514 	iface->mclk = devm_clk_get(dev, "mclk");
515 	if (IS_ERR(iface->mclk)) {
516 		ret = PTR_ERR(iface->mclk);
517 		if (ret == -ENOENT) {
518 			iface->mclk = NULL;
519 		} else {
520 			if (ret != -EPROBE_DEFER)
521 				dev_err(dev, "failed to get mclk: %d\n", ret);
522 			return ret;
523 		}
524 	}
525 
526 	return devm_snd_soc_register_component(dev,
527 					&axg_tdm_iface_component_drv, dai_drv,
528 					ARRAY_SIZE(axg_tdm_iface_dai_drv));
529 }
530 
531 static struct platform_driver axg_tdm_iface_pdrv = {
532 	.probe = axg_tdm_iface_probe,
533 	.driver = {
534 		.name = "axg-tdm-iface",
535 		.of_match_table = axg_tdm_iface_of_match,
536 	},
537 };
538 module_platform_driver(axg_tdm_iface_pdrv);
539 
540 MODULE_DESCRIPTION("Amlogic AXG TDM interface driver");
541 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
542 MODULE_LICENSE("GPL v2");
543