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  1// SPDX-License-Identifier: GPL-2.0
  2//
  3// Copyright (c) 2020 BayLibre, SAS.
  4// Author: Jerome Brunet <jbrunet@baylibre.com>
  5
  6#include <linux/bitfield.h>
  7#include <linux/clk.h>
  8#include <sound/pcm_params.h>
  9#include <sound/soc.h>
 10#include <sound/soc-dai.h>
 11
 12#include "aiu.h"
 13
 14#define AIU_I2S_SOURCE_DESC_MODE_8CH	BIT(0)
 15#define AIU_I2S_SOURCE_DESC_MODE_24BIT	BIT(5)
 16#define AIU_I2S_SOURCE_DESC_MODE_32BIT	BIT(9)
 17#define AIU_I2S_SOURCE_DESC_MODE_SPLIT	BIT(11)
 18#define AIU_RST_SOFT_I2S_FAST		BIT(0)
 19
 20#define AIU_I2S_DAC_CFG_MSB_FIRST	BIT(2)
 21#define AIU_I2S_MISC_HOLD_EN		BIT(2)
 22#define AIU_CLK_CTRL_I2S_DIV_EN		BIT(0)
 23#define AIU_CLK_CTRL_I2S_DIV		GENMASK(3, 2)
 24#define AIU_CLK_CTRL_AOCLK_INVERT	BIT(6)
 25#define AIU_CLK_CTRL_LRCLK_INVERT	BIT(7)
 26#define AIU_CLK_CTRL_LRCLK_SKEW		GENMASK(9, 8)
 27#define AIU_CLK_CTRL_MORE_HDMI_AMCLK	BIT(6)
 28#define AIU_CLK_CTRL_MORE_I2S_DIV	GENMASK(5, 0)
 29#define AIU_CODEC_DAC_LRCLK_CTRL_DIV	GENMASK(11, 0)
 30
 31static void aiu_encoder_i2s_divider_enable(struct snd_soc_component *component,
 32					   bool enable)
 33{
 34	snd_soc_component_update_bits(component, AIU_CLK_CTRL,
 35				      AIU_CLK_CTRL_I2S_DIV_EN,
 36				      enable ? AIU_CLK_CTRL_I2S_DIV_EN : 0);
 37}
 38
 39static void aiu_encoder_i2s_hold(struct snd_soc_component *component,
 40				 bool enable)
 41{
 42	snd_soc_component_update_bits(component, AIU_I2S_MISC,
 43				      AIU_I2S_MISC_HOLD_EN,
 44				      enable ? AIU_I2S_MISC_HOLD_EN : 0);
 45}
 46
 47static int aiu_encoder_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
 48				   struct snd_soc_dai *dai)
 49{
 50	struct snd_soc_component *component = dai->component;
 51
 52	switch (cmd) {
 53	case SNDRV_PCM_TRIGGER_START:
 54	case SNDRV_PCM_TRIGGER_RESUME:
 55	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 56		aiu_encoder_i2s_hold(component, false);
 57		return 0;
 58
 59	case SNDRV_PCM_TRIGGER_STOP:
 60	case SNDRV_PCM_TRIGGER_SUSPEND:
 61	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 62		aiu_encoder_i2s_hold(component, true);
 63		return 0;
 64
 65	default:
 66		return -EINVAL;
 67	}
 68}
 69
 70static int aiu_encoder_i2s_setup_desc(struct snd_soc_component *component,
 71				      struct snd_pcm_hw_params *params)
 72{
 73	/* Always operate in split (classic interleaved) mode */
 74	unsigned int desc = AIU_I2S_SOURCE_DESC_MODE_SPLIT;
 75
 76	/* Reset required to update the pipeline */
 77	snd_soc_component_write(component, AIU_RST_SOFT, AIU_RST_SOFT_I2S_FAST);
 78	snd_soc_component_read(component, AIU_I2S_SYNC);
 79
 80	switch (params_physical_width(params)) {
 81	case 16: /* Nothing to do */
 82		break;
 83
 84	case 32:
 85		desc |= (AIU_I2S_SOURCE_DESC_MODE_24BIT |
 86			 AIU_I2S_SOURCE_DESC_MODE_32BIT);
 87		break;
 88
 89	default:
 90		return -EINVAL;
 91	}
 92
 93	switch (params_channels(params)) {
 94	case 2: /* Nothing to do */
 95		break;
 96	case 8:
 97		desc |= AIU_I2S_SOURCE_DESC_MODE_8CH;
 98		break;
 99	default:
100		return -EINVAL;
101	}
102
103	snd_soc_component_update_bits(component, AIU_I2S_SOURCE_DESC,
104				      AIU_I2S_SOURCE_DESC_MODE_8CH |
105				      AIU_I2S_SOURCE_DESC_MODE_24BIT |
106				      AIU_I2S_SOURCE_DESC_MODE_32BIT |
107				      AIU_I2S_SOURCE_DESC_MODE_SPLIT,
108				      desc);
109
110	return 0;
111}
112
113static int aiu_encoder_i2s_set_legacy_div(struct snd_soc_component *component,
114					  struct snd_pcm_hw_params *params,
115					  unsigned int bs)
116{
117	switch (bs) {
118	case 1:
119	case 2:
120	case 4:
121	case 8:
122		/* These are the only valid legacy dividers */
123		break;
124
125	default:
126		dev_err(component->dev, "Unsupported i2s divider: %u\n", bs);
127		return -EINVAL;
128	}
129
130	snd_soc_component_update_bits(component, AIU_CLK_CTRL,
131				      AIU_CLK_CTRL_I2S_DIV,
132				      FIELD_PREP(AIU_CLK_CTRL_I2S_DIV,
133						 __ffs(bs)));
134
135	snd_soc_component_update_bits(component, AIU_CLK_CTRL_MORE,
136				      AIU_CLK_CTRL_MORE_I2S_DIV,
137				      FIELD_PREP(AIU_CLK_CTRL_MORE_I2S_DIV,
138						 0));
139
140	return 0;
141}
142
143static int aiu_encoder_i2s_set_more_div(struct snd_soc_component *component,
144					struct snd_pcm_hw_params *params,
145					unsigned int bs)
146{
147	/*
148	 * NOTE: this HW is odd.
149	 * In most configuration, the i2s divider is 'mclk / blck'.
150	 * However, in 16 bits - 8ch mode, this factor needs to be
151	 * increased by 50% to get the correct output rate.
152	 * No idea why !
153	 */
154	if (params_width(params) == 16 && params_channels(params) == 8) {
155		if (bs % 2) {
156			dev_err(component->dev,
157				"Cannot increase i2s divider by 50%%\n");
158			return -EINVAL;
159		}
160		bs += bs / 2;
161	}
162
163	/* Use CLK_MORE for mclk to bclk divider */
164	snd_soc_component_update_bits(component, AIU_CLK_CTRL,
165				      AIU_CLK_CTRL_I2S_DIV,
166				      FIELD_PREP(AIU_CLK_CTRL_I2S_DIV, 0));
167
168	snd_soc_component_update_bits(component, AIU_CLK_CTRL_MORE,
169				      AIU_CLK_CTRL_MORE_I2S_DIV,
170				      FIELD_PREP(AIU_CLK_CTRL_MORE_I2S_DIV,
171						 bs - 1));
172
173	return 0;
174}
175
176static int aiu_encoder_i2s_set_clocks(struct snd_soc_component *component,
177				      struct snd_pcm_hw_params *params)
178{
179	struct aiu *aiu = snd_soc_component_get_drvdata(component);
180	unsigned int srate = params_rate(params);
181	unsigned int fs, bs;
182	int ret;
183
184	/* Get the oversampling factor */
185	fs = DIV_ROUND_CLOSEST(clk_get_rate(aiu->i2s.clks[MCLK].clk), srate);
186
187	if (fs % 64)
188		return -EINVAL;
189
190	/* Send data MSB first */
191	snd_soc_component_update_bits(component, AIU_I2S_DAC_CFG,
192				      AIU_I2S_DAC_CFG_MSB_FIRST,
193				      AIU_I2S_DAC_CFG_MSB_FIRST);
194
195	/* Set bclk to lrlck ratio */
196	snd_soc_component_update_bits(component, AIU_CODEC_DAC_LRCLK_CTRL,
197				      AIU_CODEC_DAC_LRCLK_CTRL_DIV,
198				      FIELD_PREP(AIU_CODEC_DAC_LRCLK_CTRL_DIV,
199						 64 - 1));
200
201	bs = fs / 64;
202
203	if (aiu->platform->has_clk_ctrl_more_i2s_div)
204		ret = aiu_encoder_i2s_set_more_div(component, params, bs);
205	else
206		ret = aiu_encoder_i2s_set_legacy_div(component, params, bs);
207
208	if (ret)
209		return ret;
210
211	/* Make sure amclk is used for HDMI i2s as well */
212	snd_soc_component_update_bits(component, AIU_CLK_CTRL_MORE,
213				      AIU_CLK_CTRL_MORE_HDMI_AMCLK,
214				      AIU_CLK_CTRL_MORE_HDMI_AMCLK);
215
216	return 0;
217}
218
219static int aiu_encoder_i2s_hw_params(struct snd_pcm_substream *substream,
220				     struct snd_pcm_hw_params *params,
221				     struct snd_soc_dai *dai)
222{
223	struct snd_soc_component *component = dai->component;
224	int ret;
225
226	/* Disable the clock while changing the settings */
227	aiu_encoder_i2s_divider_enable(component, false);
228
229	ret = aiu_encoder_i2s_setup_desc(component, params);
230	if (ret) {
231		dev_err(dai->dev, "setting i2s desc failed\n");
232		return ret;
233	}
234
235	ret = aiu_encoder_i2s_set_clocks(component, params);
236	if (ret) {
237		dev_err(dai->dev, "setting i2s clocks failed\n");
238		return ret;
239	}
240
241	aiu_encoder_i2s_divider_enable(component, true);
242
243	return 0;
244}
245
246static int aiu_encoder_i2s_hw_free(struct snd_pcm_substream *substream,
247				   struct snd_soc_dai *dai)
248{
249	struct snd_soc_component *component = dai->component;
250
251	aiu_encoder_i2s_divider_enable(component, false);
252
253	return 0;
254}
255
256static int aiu_encoder_i2s_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
257{
258	struct snd_soc_component *component = dai->component;
259	unsigned int inv = fmt & SND_SOC_DAIFMT_INV_MASK;
260	unsigned int val = 0;
261	unsigned int skew;
262
263	/* Only CPU Master / Codec Slave supported ATM */
264	if ((fmt & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBS_CFS)
265		return -EINVAL;
266
267	if (inv == SND_SOC_DAIFMT_NB_IF ||
268	    inv == SND_SOC_DAIFMT_IB_IF)
269		val |= AIU_CLK_CTRL_LRCLK_INVERT;
270
271	if (inv == SND_SOC_DAIFMT_IB_NF ||
272	    inv == SND_SOC_DAIFMT_IB_IF)
273		val |= AIU_CLK_CTRL_AOCLK_INVERT;
274
275	/* Signal skew */
276	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
277	case SND_SOC_DAIFMT_I2S:
278		/* Invert sample clock for i2s */
279		val ^= AIU_CLK_CTRL_LRCLK_INVERT;
280		skew = 1;
281		break;
282	case SND_SOC_DAIFMT_LEFT_J:
283		skew = 0;
284		break;
285	default:
286		return -EINVAL;
287	}
288
289	val |= FIELD_PREP(AIU_CLK_CTRL_LRCLK_SKEW, skew);
290	snd_soc_component_update_bits(component, AIU_CLK_CTRL,
291				      AIU_CLK_CTRL_LRCLK_INVERT |
292				      AIU_CLK_CTRL_AOCLK_INVERT |
293				      AIU_CLK_CTRL_LRCLK_SKEW,
294				      val);
295
296	return 0;
297}
298
299static int aiu_encoder_i2s_set_sysclk(struct snd_soc_dai *dai, int clk_id,
300				      unsigned int freq, int dir)
301{
302	struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
303	int ret;
304
305	if (WARN_ON(clk_id != 0))
306		return -EINVAL;
307
308	if (dir == SND_SOC_CLOCK_IN)
309		return 0;
310
311	ret = clk_set_rate(aiu->i2s.clks[MCLK].clk, freq);
312	if (ret)
313		dev_err(dai->dev, "Failed to set sysclk to %uHz", freq);
314
315	return ret;
316}
317
318static const unsigned int hw_channels[] = {2, 8};
319static const struct snd_pcm_hw_constraint_list hw_channel_constraints = {
320	.list = hw_channels,
321	.count = ARRAY_SIZE(hw_channels),
322	.mask = 0,
323};
324
325static int aiu_encoder_i2s_startup(struct snd_pcm_substream *substream,
326				   struct snd_soc_dai *dai)
327{
328	struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
329	int ret;
330
331	/* Make sure the encoder gets either 2 or 8 channels */
332	ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
333					 SNDRV_PCM_HW_PARAM_CHANNELS,
334					 &hw_channel_constraints);
335	if (ret) {
336		dev_err(dai->dev, "adding channels constraints failed\n");
337		return ret;
338	}
339
340	ret = clk_bulk_prepare_enable(aiu->i2s.clk_num, aiu->i2s.clks);
341	if (ret)
342		dev_err(dai->dev, "failed to enable i2s clocks\n");
343
344	return ret;
345}
346
347static void aiu_encoder_i2s_shutdown(struct snd_pcm_substream *substream,
348				     struct snd_soc_dai *dai)
349{
350	struct aiu *aiu = snd_soc_component_get_drvdata(dai->component);
351
352	clk_bulk_disable_unprepare(aiu->i2s.clk_num, aiu->i2s.clks);
353}
354
355const struct snd_soc_dai_ops aiu_encoder_i2s_dai_ops = {
356	.trigger	= aiu_encoder_i2s_trigger,
357	.hw_params	= aiu_encoder_i2s_hw_params,
358	.hw_free	= aiu_encoder_i2s_hw_free,
359	.set_fmt	= aiu_encoder_i2s_set_fmt,
360	.set_sysclk	= aiu_encoder_i2s_set_sysclk,
361	.startup	= aiu_encoder_i2s_startup,
362	.shutdown	= aiu_encoder_i2s_shutdown,
363};
364