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  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 <linux/regmap.h>
 10#include <sound/soc.h>
 11#include <sound/soc-dai.h>
 12#include <sound/pcm_params.h>
 13#include <sound/pcm_iec958.h>
 14
 15/*
 16 * NOTE:
 17 * The meaning of bits SPDIFOUT_CTRL0_XXX_SEL is actually the opposite
 18 * of what the documentation says. Manual control on V, U and C bits is
 19 * applied when the related sel bits are cleared
 20 */
 21
 22#define SPDIFOUT_STAT			0x00
 23#define SPDIFOUT_GAIN0			0x04
 24#define SPDIFOUT_GAIN1			0x08
 25#define SPDIFOUT_CTRL0			0x0c
 26#define  SPDIFOUT_CTRL0_EN		BIT(31)
 27#define  SPDIFOUT_CTRL0_RST_OUT		BIT(29)
 28#define  SPDIFOUT_CTRL0_RST_IN		BIT(28)
 29#define  SPDIFOUT_CTRL0_USEL		BIT(26)
 30#define  SPDIFOUT_CTRL0_USET		BIT(25)
 31#define  SPDIFOUT_CTRL0_CHSTS_SEL	BIT(24)
 32#define  SPDIFOUT_CTRL0_DATA_SEL	BIT(20)
 33#define  SPDIFOUT_CTRL0_MSB_FIRST	BIT(19)
 34#define  SPDIFOUT_CTRL0_VSEL		BIT(18)
 35#define  SPDIFOUT_CTRL0_VSET		BIT(17)
 36#define  SPDIFOUT_CTRL0_MASK_MASK	GENMASK(11, 4)
 37#define  SPDIFOUT_CTRL0_MASK(x)		((x) << 4)
 38#define SPDIFOUT_CTRL1			0x10
 39#define  SPDIFOUT_CTRL1_MSB_POS_MASK	GENMASK(12, 8)
 40#define  SPDIFOUT_CTRL1_MSB_POS(x)	((x) << 8)
 41#define  SPDIFOUT_CTRL1_TYPE_MASK	GENMASK(6, 4)
 42#define  SPDIFOUT_CTRL1_TYPE(x)		((x) << 4)
 43#define SPDIFOUT_PREAMB			0x14
 44#define SPDIFOUT_SWAP			0x18
 45#define SPDIFOUT_CHSTS0			0x1c
 46#define SPDIFOUT_CHSTS1			0x20
 47#define SPDIFOUT_CHSTS2			0x24
 48#define SPDIFOUT_CHSTS3			0x28
 49#define SPDIFOUT_CHSTS4			0x2c
 50#define SPDIFOUT_CHSTS5			0x30
 51#define SPDIFOUT_CHSTS6			0x34
 52#define SPDIFOUT_CHSTS7			0x38
 53#define SPDIFOUT_CHSTS8			0x3c
 54#define SPDIFOUT_CHSTS9			0x40
 55#define SPDIFOUT_CHSTSA			0x44
 56#define SPDIFOUT_CHSTSB			0x48
 57#define SPDIFOUT_MUTE_VAL		0x4c
 58
 59struct axg_spdifout {
 60	struct regmap *map;
 61	struct clk *mclk;
 62	struct clk *pclk;
 63};
 64
 65static void axg_spdifout_enable(struct regmap *map)
 66{
 67	/* Apply both reset */
 68	regmap_update_bits(map, SPDIFOUT_CTRL0,
 69			   SPDIFOUT_CTRL0_RST_OUT | SPDIFOUT_CTRL0_RST_IN,
 70			   0);
 71
 72	/* Clear out reset before in reset */
 73	regmap_update_bits(map, SPDIFOUT_CTRL0,
 74			   SPDIFOUT_CTRL0_RST_OUT, SPDIFOUT_CTRL0_RST_OUT);
 75	regmap_update_bits(map, SPDIFOUT_CTRL0,
 76			   SPDIFOUT_CTRL0_RST_IN,  SPDIFOUT_CTRL0_RST_IN);
 77
 78	/* Enable spdifout */
 79	regmap_update_bits(map, SPDIFOUT_CTRL0, SPDIFOUT_CTRL0_EN,
 80			   SPDIFOUT_CTRL0_EN);
 81}
 82
 83static void axg_spdifout_disable(struct regmap *map)
 84{
 85	regmap_update_bits(map, SPDIFOUT_CTRL0, SPDIFOUT_CTRL0_EN, 0);
 86}
 87
 88static int axg_spdifout_trigger(struct snd_pcm_substream *substream, int cmd,
 89				struct snd_soc_dai *dai)
 90{
 91	struct axg_spdifout *priv = snd_soc_dai_get_drvdata(dai);
 92
 93	switch (cmd) {
 94	case SNDRV_PCM_TRIGGER_START:
 95	case SNDRV_PCM_TRIGGER_RESUME:
 96	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 97		axg_spdifout_enable(priv->map);
 98		return 0;
 99
100	case SNDRV_PCM_TRIGGER_STOP:
101	case SNDRV_PCM_TRIGGER_SUSPEND:
102	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
103		axg_spdifout_disable(priv->map);
104		return 0;
105
106	default:
107		return -EINVAL;
108	}
109}
110
111static int axg_spdifout_mute(struct snd_soc_dai *dai, int mute, int direction)
112{
113	struct axg_spdifout *priv = snd_soc_dai_get_drvdata(dai);
114
115	/* Use spdif valid bit to perform digital mute */
116	regmap_update_bits(priv->map, SPDIFOUT_CTRL0, SPDIFOUT_CTRL0_VSET,
117			   mute ? SPDIFOUT_CTRL0_VSET : 0);
118
119	return 0;
120}
121
122static int axg_spdifout_sample_fmt(struct snd_pcm_hw_params *params,
123				   struct snd_soc_dai *dai)
124{
125	struct axg_spdifout *priv = snd_soc_dai_get_drvdata(dai);
126	unsigned int val;
127
128	/* Set the samples spdifout will pull from the FIFO */
129	switch (params_channels(params)) {
130	case 1:
131		val = SPDIFOUT_CTRL0_MASK(0x1);
132		break;
133	case 2:
134		val = SPDIFOUT_CTRL0_MASK(0x3);
135		break;
136	default:
137		dev_err(dai->dev, "too many channels for spdif dai: %u\n",
138			params_channels(params));
139		return -EINVAL;
140	}
141
142	regmap_update_bits(priv->map, SPDIFOUT_CTRL0,
143			   SPDIFOUT_CTRL0_MASK_MASK, val);
144
145	/* FIFO data are arranged in chunks of 64bits */
146	switch (params_physical_width(params)) {
147	case 8:
148		/* 8 samples of 8 bits */
149		val = SPDIFOUT_CTRL1_TYPE(0);
150		break;
151	case 16:
152		/* 4 samples of 16 bits - right justified */
153		val = SPDIFOUT_CTRL1_TYPE(2);
154		break;
155	case 32:
156		/* 2 samples of 32 bits - right justified */
157		val = SPDIFOUT_CTRL1_TYPE(4);
158		break;
159	default:
160		dev_err(dai->dev, "Unsupported physical width: %u\n",
161			params_physical_width(params));
162		return -EINVAL;
163	}
164
165	/* Position of the MSB in FIFO samples */
166	val |= SPDIFOUT_CTRL1_MSB_POS(params_width(params) - 1);
167
168	regmap_update_bits(priv->map, SPDIFOUT_CTRL1,
169			   SPDIFOUT_CTRL1_MSB_POS_MASK |
170			   SPDIFOUT_CTRL1_TYPE_MASK, val);
171
172	regmap_update_bits(priv->map, SPDIFOUT_CTRL0,
173			   SPDIFOUT_CTRL0_MSB_FIRST | SPDIFOUT_CTRL0_DATA_SEL,
174			   0);
175
176	return 0;
177}
178
179static int axg_spdifout_set_chsts(struct snd_pcm_hw_params *params,
180				  struct snd_soc_dai *dai)
181{
182	struct axg_spdifout *priv = snd_soc_dai_get_drvdata(dai);
183	unsigned int offset;
184	int ret;
185	u8 cs[4];
186	u32 val;
187
188	ret = snd_pcm_create_iec958_consumer_hw_params(params, cs, 4);
189	if (ret < 0) {
190		dev_err(dai->dev, "Creating IEC958 channel status failed %d\n",
191			ret);
192		return ret;
193	}
194	val = cs[0] | cs[1] << 8 | cs[2] << 16 | cs[3] << 24;
195
196	/* Setup channel status A bits [31 - 0]*/
197	regmap_write(priv->map, SPDIFOUT_CHSTS0, val);
198
199	/* Clear channel status A bits [191 - 32] */
200	for (offset = SPDIFOUT_CHSTS1; offset <= SPDIFOUT_CHSTS5;
201	     offset += regmap_get_reg_stride(priv->map))
202		regmap_write(priv->map, offset, 0);
203
204	/* Setup channel status B bits [31 - 0]*/
205	regmap_write(priv->map, SPDIFOUT_CHSTS6, val);
206
207	/* Clear channel status B bits [191 - 32] */
208	for (offset = SPDIFOUT_CHSTS7; offset <= SPDIFOUT_CHSTSB;
209	     offset += regmap_get_reg_stride(priv->map))
210		regmap_write(priv->map, offset, 0);
211
212	return 0;
213}
214
215static int axg_spdifout_hw_params(struct snd_pcm_substream *substream,
216				  struct snd_pcm_hw_params *params,
217				  struct snd_soc_dai *dai)
218{
219	struct axg_spdifout *priv = snd_soc_dai_get_drvdata(dai);
220	unsigned int rate = params_rate(params);
221	int ret;
222
223	/* 2 * 32bits per subframe * 2 channels = 128 */
224	ret = clk_set_rate(priv->mclk, rate * 128);
225	if (ret) {
226		dev_err(dai->dev, "failed to set spdif clock\n");
227		return ret;
228	}
229
230	ret = axg_spdifout_sample_fmt(params, dai);
231	if (ret) {
232		dev_err(dai->dev, "failed to setup sample format\n");
233		return ret;
234	}
235
236	ret = axg_spdifout_set_chsts(params, dai);
237	if (ret) {
238		dev_err(dai->dev, "failed to setup channel status words\n");
239		return ret;
240	}
241
242	return 0;
243}
244
245static int axg_spdifout_startup(struct snd_pcm_substream *substream,
246				struct snd_soc_dai *dai)
247{
248	struct axg_spdifout *priv = snd_soc_dai_get_drvdata(dai);
249	int ret;
250
251	/* Clock the spdif output block */
252	ret = clk_prepare_enable(priv->pclk);
253	if (ret) {
254		dev_err(dai->dev, "failed to enable pclk\n");
255		return ret;
256	}
257
258	/* Make sure the block is initially stopped */
259	axg_spdifout_disable(priv->map);
260
261	/* Insert data from bit 27 lsb first */
262	regmap_update_bits(priv->map, SPDIFOUT_CTRL0,
263			   SPDIFOUT_CTRL0_MSB_FIRST | SPDIFOUT_CTRL0_DATA_SEL,
264			   0);
265
266	/* Manual control of V, C and U, U = 0 */
267	regmap_update_bits(priv->map, SPDIFOUT_CTRL0,
268			   SPDIFOUT_CTRL0_CHSTS_SEL | SPDIFOUT_CTRL0_VSEL |
269			   SPDIFOUT_CTRL0_USEL | SPDIFOUT_CTRL0_USET,
270			   0);
271
272	/* Static SWAP configuration ATM */
273	regmap_write(priv->map, SPDIFOUT_SWAP, 0x10);
274
275	return 0;
276}
277
278static void axg_spdifout_shutdown(struct snd_pcm_substream *substream,
279				  struct snd_soc_dai *dai)
280{
281	struct axg_spdifout *priv = snd_soc_dai_get_drvdata(dai);
282
283	clk_disable_unprepare(priv->pclk);
284}
285
286static const struct snd_soc_dai_ops axg_spdifout_ops = {
287	.trigger	= axg_spdifout_trigger,
288	.mute_stream	= axg_spdifout_mute,
289	.hw_params	= axg_spdifout_hw_params,
290	.startup	= axg_spdifout_startup,
291	.shutdown	= axg_spdifout_shutdown,
292	.no_capture_mute = 1,
293};
294
295static struct snd_soc_dai_driver axg_spdifout_dai_drv[] = {
296	{
297		.name = "SPDIF Output",
298		.playback = {
299			.stream_name	= "Playback",
300			.channels_min	= 1,
301			.channels_max	= 2,
302			.rates		= (SNDRV_PCM_RATE_32000  |
303					   SNDRV_PCM_RATE_44100  |
304					   SNDRV_PCM_RATE_48000  |
305					   SNDRV_PCM_RATE_88200  |
306					   SNDRV_PCM_RATE_96000  |
307					   SNDRV_PCM_RATE_176400 |
308					   SNDRV_PCM_RATE_192000),
309			.formats	= (SNDRV_PCM_FMTBIT_S8     |
310					   SNDRV_PCM_FMTBIT_S16_LE |
311					   SNDRV_PCM_FMTBIT_S20_LE |
312					   SNDRV_PCM_FMTBIT_S24_LE),
313		},
314		.ops = &axg_spdifout_ops,
315	},
316};
317
318static const char * const spdifout_sel_texts[] = {
319	"IN 0", "IN 1", "IN 2",
320};
321
322static SOC_ENUM_SINGLE_DECL(axg_spdifout_sel_enum, SPDIFOUT_CTRL1, 24,
323			    spdifout_sel_texts);
324
325static const struct snd_kcontrol_new axg_spdifout_in_mux =
326	SOC_DAPM_ENUM("Input Source", axg_spdifout_sel_enum);
327
328static const struct snd_soc_dapm_widget axg_spdifout_dapm_widgets[] = {
329	SND_SOC_DAPM_AIF_IN("IN 0", NULL, 0, SND_SOC_NOPM, 0, 0),
330	SND_SOC_DAPM_AIF_IN("IN 1", NULL, 0, SND_SOC_NOPM, 0, 0),
331	SND_SOC_DAPM_AIF_IN("IN 2", NULL, 0, SND_SOC_NOPM, 0, 0),
332	SND_SOC_DAPM_MUX("SRC SEL", SND_SOC_NOPM, 0, 0, &axg_spdifout_in_mux),
333};
334
335static const struct snd_soc_dapm_route axg_spdifout_dapm_routes[] = {
336	{ "SRC SEL", "IN 0", "IN 0" },
337	{ "SRC SEL", "IN 1", "IN 1" },
338	{ "SRC SEL", "IN 2", "IN 2" },
339	{ "Playback", NULL, "SRC SEL" },
340};
341
342static const struct snd_kcontrol_new axg_spdifout_controls[] = {
343	SOC_DOUBLE("Playback Volume", SPDIFOUT_GAIN0,  0,  8, 255, 0),
344	SOC_DOUBLE("Playback Switch", SPDIFOUT_CTRL0, 22, 21, 1, 1),
345	SOC_SINGLE("Playback Gain Enable Switch",
346		   SPDIFOUT_CTRL1, 26, 1, 0),
347	SOC_SINGLE("Playback Channels Mix Switch",
348		   SPDIFOUT_CTRL0, 23, 1, 0),
349};
350
351static int axg_spdifout_set_bias_level(struct snd_soc_component *component,
352				       enum snd_soc_bias_level level)
353{
354	struct axg_spdifout *priv = snd_soc_component_get_drvdata(component);
355	enum snd_soc_bias_level now =
356		snd_soc_component_get_bias_level(component);
357	int ret = 0;
358
359	switch (level) {
360	case SND_SOC_BIAS_PREPARE:
361		if (now == SND_SOC_BIAS_STANDBY)
362			ret = clk_prepare_enable(priv->mclk);
363		break;
364
365	case SND_SOC_BIAS_STANDBY:
366		if (now == SND_SOC_BIAS_PREPARE)
367			clk_disable_unprepare(priv->mclk);
368		break;
369
370	case SND_SOC_BIAS_OFF:
371	case SND_SOC_BIAS_ON:
372		break;
373	}
374
375	return ret;
376}
377
378static const struct snd_soc_component_driver axg_spdifout_component_drv = {
379	.controls		= axg_spdifout_controls,
380	.num_controls		= ARRAY_SIZE(axg_spdifout_controls),
381	.dapm_widgets		= axg_spdifout_dapm_widgets,
382	.num_dapm_widgets	= ARRAY_SIZE(axg_spdifout_dapm_widgets),
383	.dapm_routes		= axg_spdifout_dapm_routes,
384	.num_dapm_routes	= ARRAY_SIZE(axg_spdifout_dapm_routes),
385	.set_bias_level		= axg_spdifout_set_bias_level,
386	.legacy_dai_naming	= 1,
387};
388
389static const struct regmap_config axg_spdifout_regmap_cfg = {
390	.reg_bits	= 32,
391	.val_bits	= 32,
392	.reg_stride	= 4,
393	.max_register	= SPDIFOUT_MUTE_VAL,
394};
395
396static const struct of_device_id axg_spdifout_of_match[] = {
397	{ .compatible = "amlogic,axg-spdifout", },
398	{}
399};
400MODULE_DEVICE_TABLE(of, axg_spdifout_of_match);
401
402static int axg_spdifout_probe(struct platform_device *pdev)
403{
404	struct device *dev = &pdev->dev;
405	struct axg_spdifout *priv;
406	void __iomem *regs;
407
408	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
409	if (!priv)
410		return -ENOMEM;
411	platform_set_drvdata(pdev, priv);
412
413	regs = devm_platform_ioremap_resource(pdev, 0);
414	if (IS_ERR(regs))
415		return PTR_ERR(regs);
416
417	priv->map = devm_regmap_init_mmio(dev, regs, &axg_spdifout_regmap_cfg);
418	if (IS_ERR(priv->map)) {
419		dev_err(dev, "failed to init regmap: %ld\n",
420			PTR_ERR(priv->map));
421		return PTR_ERR(priv->map);
422	}
423
424	priv->pclk = devm_clk_get(dev, "pclk");
425	if (IS_ERR(priv->pclk))
426		return dev_err_probe(dev, PTR_ERR(priv->pclk), "failed to get pclk\n");
427
428	priv->mclk = devm_clk_get(dev, "mclk");
429	if (IS_ERR(priv->mclk))
430		return dev_err_probe(dev, PTR_ERR(priv->mclk), "failed to get mclk\n");
431
432	return devm_snd_soc_register_component(dev, &axg_spdifout_component_drv,
433			axg_spdifout_dai_drv, ARRAY_SIZE(axg_spdifout_dai_drv));
434}
435
436static struct platform_driver axg_spdifout_pdrv = {
437	.probe = axg_spdifout_probe,
438	.driver = {
439		.name = "axg-spdifout",
440		.of_match_table = axg_spdifout_of_match,
441	},
442};
443module_platform_driver(axg_spdifout_pdrv);
444
445MODULE_DESCRIPTION("Amlogic AXG SPDIF Output driver");
446MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
447MODULE_LICENSE("GPL v2");
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