xref: /linux/sound/soc/fsl/lpc3xxx-i2s.c (revision a9aaf1ff88a8cb99a1335c9eb76de637f0cf8c10)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 //
3 // Author: Kevin Wells <kevin.wells@nxp.com>
4 //
5 // Copyright (C) 2008 NXP Semiconductors
6 // Copyright 2023 Timesys Corporation <piotr.wojtaszczyk@timesys.com>
7 
8 #include <linux/init.h>
9 #include <linux/module.h>
10 #include <linux/interrupt.h>
11 #include <linux/device.h>
12 #include <linux/delay.h>
13 #include <linux/clk.h>
14 #include <linux/io.h>
15 
16 #include <sound/core.h>
17 #include <sound/pcm.h>
18 #include <sound/pcm_params.h>
19 #include <sound/dmaengine_pcm.h>
20 #include <sound/initval.h>
21 #include <sound/soc.h>
22 
23 #include "lpc3xxx-i2s.h"
24 
25 #define I2S_PLAYBACK_FLAG 0x1
26 #define I2S_CAPTURE_FLAG 0x2
27 
28 #define LPC3XXX_I2S_RATES ( \
29 	SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 | \
30 	SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
31 	SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000)
32 
33 #define LPC3XXX_I2S_FORMATS ( \
34 	SNDRV_PCM_FMTBIT_S8 | \
35 	SNDRV_PCM_FMTBIT_S16_LE | \
36 	SNDRV_PCM_FMTBIT_S32_LE)
37 
38 static void __lpc3xxx_find_clkdiv(u32 *clkx, u32 *clky, int freq, int xbytes, u32 clkrate)
39 {
40 	u32 i2srate;
41 	u32 idxx, idyy;
42 	u32 savedbitclkrate, diff, trate, baseclk;
43 
44 	/* Adjust rate for sample size (bits) and 2 channels and offset for
45 	 * divider in clock output
46 	 */
47 	i2srate = (freq / 100) * 2 * (8 * xbytes);
48 	i2srate = i2srate << 1;
49 	clkrate = clkrate / 100;
50 	baseclk = clkrate;
51 	*clkx = 1;
52 	*clky = 1;
53 
54 	/* Find the best divider */
55 	*clkx = *clky = 0;
56 	savedbitclkrate = 0;
57 	diff = ~0;
58 	for (idxx = 1; idxx < 0xFF; idxx++) {
59 		for (idyy = 1; idyy < 0xFF; idyy++) {
60 			trate = (baseclk * idxx) / idyy;
61 			if (abs(trate - i2srate) < diff) {
62 				diff = abs(trate - i2srate);
63 				savedbitclkrate = trate;
64 				*clkx = idxx;
65 				*clky = idyy;
66 			}
67 		}
68 	}
69 }
70 
71 static int lpc3xxx_i2s_startup(struct snd_pcm_substream *substream, struct snd_soc_dai *cpu_dai)
72 {
73 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
74 	struct device *dev = i2s_info_p->dev;
75 	u32 flag;
76 	int ret = 0;
77 
78 	guard(mutex)(&i2s_info_p->lock);
79 
80 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
81 		flag = I2S_PLAYBACK_FLAG;
82 	else
83 		flag = I2S_CAPTURE_FLAG;
84 
85 	if (flag & i2s_info_p->streams_in_use) {
86 		dev_warn(dev, "I2S channel is busy\n");
87 		ret = -EBUSY;
88 		return ret;
89 	}
90 
91 	if (i2s_info_p->streams_in_use == 0) {
92 		ret = clk_prepare_enable(i2s_info_p->clk);
93 		if (ret) {
94 			dev_err(dev, "Can't enable clock, err=%d\n", ret);
95 			return ret;
96 		}
97 	}
98 
99 	i2s_info_p->streams_in_use |= flag;
100 	return 0;
101 }
102 
103 static void lpc3xxx_i2s_shutdown(struct snd_pcm_substream *substream, struct snd_soc_dai *cpu_dai)
104 {
105 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
106 	struct regmap *regs = i2s_info_p->regs;
107 	const u32 stop_bits = (LPC3XXX_I2S_RESET | LPC3XXX_I2S_STOP);
108 	u32 flag;
109 
110 	guard(mutex)(&i2s_info_p->lock);
111 
112 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
113 		flag = I2S_PLAYBACK_FLAG;
114 		regmap_write(regs, LPC3XXX_REG_I2S_TX_RATE, 0);
115 		regmap_update_bits(regs, LPC3XXX_REG_I2S_DAO, stop_bits, stop_bits);
116 	} else {
117 		flag = I2S_CAPTURE_FLAG;
118 		regmap_write(regs, LPC3XXX_REG_I2S_RX_RATE, 0);
119 		regmap_update_bits(regs, LPC3XXX_REG_I2S_DAI, stop_bits, stop_bits);
120 	}
121 	i2s_info_p->streams_in_use &= ~flag;
122 
123 	if (i2s_info_p->streams_in_use == 0)
124 		clk_disable_unprepare(i2s_info_p->clk);
125 }
126 
127 static int lpc3xxx_i2s_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
128 				      int clk_id, unsigned int freq, int dir)
129 {
130 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
131 
132 	/* Will use in HW params later */
133 	i2s_info_p->freq = freq;
134 
135 	return 0;
136 }
137 
138 static int lpc3xxx_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
139 {
140 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
141 	struct device *dev = i2s_info_p->dev;
142 
143 	if ((fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_I2S) {
144 		dev_warn(dev, "unsupported bus format %d\n", fmt);
145 		return -EINVAL;
146 	}
147 
148 	if ((fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) != SND_SOC_DAIFMT_BP_FP) {
149 		dev_warn(dev, "unsupported clock provider %d\n", fmt);
150 		return -EINVAL;
151 	}
152 
153 	return 0;
154 }
155 
156 static int lpc3xxx_i2s_hw_params(struct snd_pcm_substream *substream,
157 				 struct snd_pcm_hw_params *params,
158 				 struct snd_soc_dai *cpu_dai)
159 {
160 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
161 	struct device *dev = i2s_info_p->dev;
162 	struct regmap *regs = i2s_info_p->regs;
163 	int xfersize;
164 	u32 tmp, clkx, clky;
165 
166 	tmp = LPC3XXX_I2S_RESET | LPC3XXX_I2S_STOP;
167 	switch (params_format(params)) {
168 	case SNDRV_PCM_FORMAT_S8:
169 		tmp |= LPC3XXX_I2S_WW8 | LPC3XXX_I2S_WS_HP(LPC3XXX_I2S_WW8_HP);
170 		xfersize = 1;
171 		break;
172 
173 	case SNDRV_PCM_FORMAT_S16_LE:
174 		tmp |= LPC3XXX_I2S_WW16 | LPC3XXX_I2S_WS_HP(LPC3XXX_I2S_WW16_HP);
175 		xfersize = 2;
176 		break;
177 
178 	case SNDRV_PCM_FORMAT_S32_LE:
179 		tmp |= LPC3XXX_I2S_WW32 | LPC3XXX_I2S_WS_HP(LPC3XXX_I2S_WW32_HP);
180 		xfersize = 4;
181 		break;
182 
183 	default:
184 		dev_warn(dev, "Unsupported audio data format %d\n", params_format(params));
185 		return -EINVAL;
186 	}
187 
188 	if (params_channels(params) == 1)
189 		tmp |= LPC3XXX_I2S_MONO;
190 
191 	__lpc3xxx_find_clkdiv(&clkx, &clky, i2s_info_p->freq, xfersize, i2s_info_p->clkrate);
192 
193 	dev_dbg(dev, "Stream                : %s\n",
194 		substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? "playback" : "capture");
195 	dev_dbg(dev, "Desired clock rate    : %d\n", i2s_info_p->freq);
196 	dev_dbg(dev, "Base clock rate       : %d\n", i2s_info_p->clkrate);
197 	dev_dbg(dev, "Transfer size (bytes) : %d\n", xfersize);
198 	dev_dbg(dev, "Clock divider (x)     : %d\n", clkx);
199 	dev_dbg(dev, "Clock divider (y)     : %d\n", clky);
200 	dev_dbg(dev, "Channels              : %d\n", params_channels(params));
201 	dev_dbg(dev, "Data format           : %s\n", "I2S");
202 
203 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
204 		regmap_write(regs, LPC3XXX_REG_I2S_DMA1,
205 			     LPC3XXX_I2S_DMA1_TX_EN | LPC3XXX_I2S_DMA0_TX_DEPTH(4));
206 		regmap_write(regs, LPC3XXX_REG_I2S_TX_RATE, (clkx << 8) | clky);
207 		regmap_write(regs, LPC3XXX_REG_I2S_DAO, tmp);
208 	} else {
209 		regmap_write(regs, LPC3XXX_REG_I2S_DMA0,
210 			     LPC3XXX_I2S_DMA0_RX_EN | LPC3XXX_I2S_DMA1_RX_DEPTH(4));
211 		regmap_write(regs, LPC3XXX_REG_I2S_RX_RATE, (clkx << 8) | clky);
212 		regmap_write(regs, LPC3XXX_REG_I2S_DAI, tmp);
213 	}
214 
215 	return 0;
216 }
217 
218 static int lpc3xxx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
219 			       struct snd_soc_dai *cpu_dai)
220 {
221 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
222 	struct regmap *regs = i2s_info_p->regs;
223 	int ret = 0;
224 
225 	switch (cmd) {
226 	case SNDRV_PCM_TRIGGER_STOP:
227 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
228 	case SNDRV_PCM_TRIGGER_SUSPEND:
229 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
230 			regmap_update_bits(regs, LPC3XXX_REG_I2S_DAO,
231 					   LPC3XXX_I2S_STOP, LPC3XXX_I2S_STOP);
232 		else
233 			regmap_update_bits(regs, LPC3XXX_REG_I2S_DAI,
234 					   LPC3XXX_I2S_STOP, LPC3XXX_I2S_STOP);
235 		break;
236 
237 	case SNDRV_PCM_TRIGGER_START:
238 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
239 	case SNDRV_PCM_TRIGGER_RESUME:
240 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
241 			regmap_update_bits(regs, LPC3XXX_REG_I2S_DAO,
242 					   (LPC3XXX_I2S_RESET | LPC3XXX_I2S_STOP), 0);
243 		else
244 			regmap_update_bits(regs, LPC3XXX_REG_I2S_DAI,
245 					   (LPC3XXX_I2S_RESET | LPC3XXX_I2S_STOP), 0);
246 		break;
247 	default:
248 		ret = -EINVAL;
249 	}
250 
251 	return ret;
252 }
253 
254 static int lpc3xxx_i2s_dai_probe(struct snd_soc_dai *dai)
255 {
256 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(dai);
257 
258 	snd_soc_dai_init_dma_data(dai, &i2s_info_p->playback_dma_config,
259 				  &i2s_info_p->capture_dma_config);
260 	return 0;
261 }
262 
263 const struct snd_soc_dai_ops lpc3xxx_i2s_dai_ops = {
264 	.probe	= lpc3xxx_i2s_dai_probe,
265 	.startup = lpc3xxx_i2s_startup,
266 	.shutdown = lpc3xxx_i2s_shutdown,
267 	.trigger = lpc3xxx_i2s_trigger,
268 	.hw_params = lpc3xxx_i2s_hw_params,
269 	.set_sysclk = lpc3xxx_i2s_set_dai_sysclk,
270 	.set_fmt = lpc3xxx_i2s_set_dai_fmt,
271 };
272 
273 struct snd_soc_dai_driver lpc3xxx_i2s_dai_driver = {
274 	.playback = {
275 		.channels_min = 1,
276 		.channels_max = 2,
277 		.rates = LPC3XXX_I2S_RATES,
278 		.formats = LPC3XXX_I2S_FORMATS,
279 		},
280 	.capture = {
281 		.channels_min = 1,
282 		.channels_max = 2,
283 		.rates = LPC3XXX_I2S_RATES,
284 		.formats = LPC3XXX_I2S_FORMATS,
285 		},
286 	.ops = &lpc3xxx_i2s_dai_ops,
287 	.symmetric_rate = 1,
288 	.symmetric_channels = 1,
289 	.symmetric_sample_bits = 1,
290 };
291 
292 static const struct snd_soc_component_driver lpc32xx_i2s_component = {
293 	.name = "lpc32xx-i2s",
294 	.legacy_dai_naming = 1,
295 };
296 
297 static const struct regmap_config lpc32xx_i2s_regconfig = {
298 	.reg_bits = 32,
299 	.reg_stride = 4,
300 	.val_bits = 32,
301 	.max_register = LPC3XXX_REG_I2S_RX_RATE,
302 };
303 
304 static int lpc32xx_i2s_probe(struct platform_device *pdev)
305 {
306 	struct device *dev = &pdev->dev;
307 	struct lpc3xxx_i2s_info *i2s_info_p;
308 	struct resource *res;
309 	void __iomem *iomem;
310 	int ret;
311 
312 	i2s_info_p = devm_kzalloc(dev, sizeof(*i2s_info_p), GFP_KERNEL);
313 	if (!i2s_info_p)
314 		return -ENOMEM;
315 
316 	platform_set_drvdata(pdev, i2s_info_p);
317 	i2s_info_p->dev = dev;
318 
319 	iomem = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
320 	if (IS_ERR(iomem))
321 		return dev_err_probe(dev, PTR_ERR(iomem), "Can't map registers\n");
322 
323 	i2s_info_p->regs = devm_regmap_init_mmio(dev, iomem, &lpc32xx_i2s_regconfig);
324 	if (IS_ERR(i2s_info_p->regs))
325 		return dev_err_probe(dev, PTR_ERR(i2s_info_p->regs),
326 				     "failed to init register map: %pe\n", i2s_info_p->regs);
327 
328 	i2s_info_p->clk = devm_clk_get(dev, NULL);
329 	if (IS_ERR(i2s_info_p->clk))
330 		return dev_err_probe(dev, PTR_ERR(i2s_info_p->clk), "Can't get clock\n");
331 
332 	i2s_info_p->clkrate = clk_get_rate(i2s_info_p->clk);
333 	if (i2s_info_p->clkrate == 0)
334 		return dev_err_probe(dev, -EINVAL, "Invalid returned clock rate\n");
335 
336 	mutex_init(&i2s_info_p->lock);
337 
338 	ret = devm_snd_soc_register_component(dev, &lpc32xx_i2s_component,
339 					      &lpc3xxx_i2s_dai_driver, 1);
340 	if (ret)
341 		return dev_err_probe(dev, ret, "Can't register cpu_dai component\n");
342 
343 	i2s_info_p->playback_dma_config.addr = (dma_addr_t)(res->start + LPC3XXX_REG_I2S_TX_FIFO);
344 	i2s_info_p->playback_dma_config.maxburst = 4;
345 
346 	i2s_info_p->capture_dma_config.addr = (dma_addr_t)(res->start + LPC3XXX_REG_I2S_RX_FIFO);
347 	i2s_info_p->capture_dma_config.maxburst = 4;
348 
349 	ret = lpc3xxx_pcm_register(pdev);
350 	if (ret)
351 		return dev_err_probe(dev, ret, "Can't register pcm component\n");
352 
353 	return 0;
354 }
355 
356 static const struct of_device_id lpc32xx_i2s_match[] = {
357 	{ .compatible = "nxp,lpc3220-i2s" },
358 	{},
359 };
360 MODULE_DEVICE_TABLE(of, lpc32xx_i2s_match);
361 
362 static struct platform_driver lpc32xx_i2s_driver = {
363 	.probe = lpc32xx_i2s_probe,
364 	.driver		= {
365 		.name	= "lpc3xxx-i2s",
366 		.of_match_table = lpc32xx_i2s_match,
367 	},
368 };
369 
370 module_platform_driver(lpc32xx_i2s_driver);
371 
372 MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
373 MODULE_AUTHOR("Piotr Wojtaszczyk <piotr.wojtaszczyk@timesys.com>");
374 MODULE_DESCRIPTION("ASoC LPC3XXX I2S interface");
375 MODULE_LICENSE("GPL");
376