xref: /linux/sound/soc/fsl/lpc3xxx-i2s.c (revision c7546e2c3cb739a3c1a2f5acaf9bb629d401afe5)
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 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 	diff = ~0;
57 	for (idxx = 1; idxx < 0xFF; idxx++) {
58 		for (idyy = 1; idyy < 0xFF; idyy++) {
59 			trate = (baseclk * idxx) / idyy;
60 			if (abs(trate - i2srate) < diff) {
61 				diff = abs(trate - i2srate);
62 				*clkx = idxx;
63 				*clky = idyy;
64 			}
65 		}
66 	}
67 }
68 
69 static int lpc3xxx_i2s_startup(struct snd_pcm_substream *substream, struct snd_soc_dai *cpu_dai)
70 {
71 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
72 	struct device *dev = i2s_info_p->dev;
73 	u32 flag;
74 	int ret = 0;
75 
76 	guard(mutex)(&i2s_info_p->lock);
77 
78 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
79 		flag = I2S_PLAYBACK_FLAG;
80 	else
81 		flag = I2S_CAPTURE_FLAG;
82 
83 	if (flag & i2s_info_p->streams_in_use) {
84 		dev_warn(dev, "I2S channel is busy\n");
85 		ret = -EBUSY;
86 		return ret;
87 	}
88 
89 	if (i2s_info_p->streams_in_use == 0) {
90 		ret = clk_prepare_enable(i2s_info_p->clk);
91 		if (ret) {
92 			dev_err(dev, "Can't enable clock, err=%d\n", ret);
93 			return ret;
94 		}
95 	}
96 
97 	i2s_info_p->streams_in_use |= flag;
98 	return 0;
99 }
100 
101 static void lpc3xxx_i2s_shutdown(struct snd_pcm_substream *substream, struct snd_soc_dai *cpu_dai)
102 {
103 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
104 	struct regmap *regs = i2s_info_p->regs;
105 	const u32 stop_bits = (LPC3XXX_I2S_RESET | LPC3XXX_I2S_STOP);
106 	u32 flag;
107 
108 	guard(mutex)(&i2s_info_p->lock);
109 
110 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
111 		flag = I2S_PLAYBACK_FLAG;
112 		regmap_write(regs, LPC3XXX_REG_I2S_TX_RATE, 0);
113 		regmap_update_bits(regs, LPC3XXX_REG_I2S_DAO, stop_bits, stop_bits);
114 	} else {
115 		flag = I2S_CAPTURE_FLAG;
116 		regmap_write(regs, LPC3XXX_REG_I2S_RX_RATE, 0);
117 		regmap_update_bits(regs, LPC3XXX_REG_I2S_DAI, stop_bits, stop_bits);
118 	}
119 	i2s_info_p->streams_in_use &= ~flag;
120 
121 	if (i2s_info_p->streams_in_use == 0)
122 		clk_disable_unprepare(i2s_info_p->clk);
123 }
124 
125 static int lpc3xxx_i2s_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
126 				      int clk_id, unsigned int freq, int dir)
127 {
128 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
129 
130 	/* Will use in HW params later */
131 	i2s_info_p->freq = freq;
132 
133 	return 0;
134 }
135 
136 static int lpc3xxx_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
137 {
138 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
139 	struct device *dev = i2s_info_p->dev;
140 
141 	if ((fmt & SND_SOC_DAIFMT_FORMAT_MASK) != SND_SOC_DAIFMT_I2S) {
142 		dev_warn(dev, "unsupported bus format %d\n", fmt);
143 		return -EINVAL;
144 	}
145 
146 	if ((fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) != SND_SOC_DAIFMT_BP_FP) {
147 		dev_warn(dev, "unsupported clock provider %d\n", fmt);
148 		return -EINVAL;
149 	}
150 
151 	return 0;
152 }
153 
154 static int lpc3xxx_i2s_hw_params(struct snd_pcm_substream *substream,
155 				 struct snd_pcm_hw_params *params,
156 				 struct snd_soc_dai *cpu_dai)
157 {
158 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
159 	struct device *dev = i2s_info_p->dev;
160 	struct regmap *regs = i2s_info_p->regs;
161 	int xfersize;
162 	u32 tmp, clkx, clky;
163 
164 	tmp = LPC3XXX_I2S_RESET | LPC3XXX_I2S_STOP;
165 	switch (params_format(params)) {
166 	case SNDRV_PCM_FORMAT_S8:
167 		tmp |= LPC3XXX_I2S_WW8 | LPC3XXX_I2S_WS_HP(LPC3XXX_I2S_WW8_HP);
168 		xfersize = 1;
169 		break;
170 
171 	case SNDRV_PCM_FORMAT_S16_LE:
172 		tmp |= LPC3XXX_I2S_WW16 | LPC3XXX_I2S_WS_HP(LPC3XXX_I2S_WW16_HP);
173 		xfersize = 2;
174 		break;
175 
176 	case SNDRV_PCM_FORMAT_S32_LE:
177 		tmp |= LPC3XXX_I2S_WW32 | LPC3XXX_I2S_WS_HP(LPC3XXX_I2S_WW32_HP);
178 		xfersize = 4;
179 		break;
180 
181 	default:
182 		dev_warn(dev, "Unsupported audio data format %d\n", params_format(params));
183 		return -EINVAL;
184 	}
185 
186 	if (params_channels(params) == 1)
187 		tmp |= LPC3XXX_I2S_MONO;
188 
189 	__lpc3xxx_find_clkdiv(&clkx, &clky, i2s_info_p->freq, xfersize, i2s_info_p->clkrate);
190 
191 	dev_dbg(dev, "Stream                : %s\n", snd_pcm_direction_name(substream->stream));
192 	dev_dbg(dev, "Desired clock rate    : %d\n", i2s_info_p->freq);
193 	dev_dbg(dev, "Base clock rate       : %d\n", i2s_info_p->clkrate);
194 	dev_dbg(dev, "Transfer size (bytes) : %d\n", xfersize);
195 	dev_dbg(dev, "Clock divider (x)     : %d\n", clkx);
196 	dev_dbg(dev, "Clock divider (y)     : %d\n", clky);
197 	dev_dbg(dev, "Channels              : %d\n", params_channels(params));
198 	dev_dbg(dev, "Data format           : %s\n", "I2S");
199 
200 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
201 		regmap_write(regs, LPC3XXX_REG_I2S_DMA1,
202 			     LPC3XXX_I2S_DMA1_TX_EN | LPC3XXX_I2S_DMA0_TX_DEPTH(4));
203 		regmap_write(regs, LPC3XXX_REG_I2S_TX_RATE, (clkx << 8) | clky);
204 		regmap_write(regs, LPC3XXX_REG_I2S_DAO, tmp);
205 	} else {
206 		regmap_write(regs, LPC3XXX_REG_I2S_DMA0,
207 			     LPC3XXX_I2S_DMA0_RX_EN | LPC3XXX_I2S_DMA1_RX_DEPTH(4));
208 		regmap_write(regs, LPC3XXX_REG_I2S_RX_RATE, (clkx << 8) | clky);
209 		regmap_write(regs, LPC3XXX_REG_I2S_DAI, tmp);
210 	}
211 
212 	return 0;
213 }
214 
215 static int lpc3xxx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
216 			       struct snd_soc_dai *cpu_dai)
217 {
218 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(cpu_dai);
219 	struct regmap *regs = i2s_info_p->regs;
220 	int ret = 0;
221 
222 	switch (cmd) {
223 	case SNDRV_PCM_TRIGGER_STOP:
224 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
225 	case SNDRV_PCM_TRIGGER_SUSPEND:
226 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
227 			regmap_update_bits(regs, LPC3XXX_REG_I2S_DAO,
228 					   LPC3XXX_I2S_STOP, LPC3XXX_I2S_STOP);
229 		else
230 			regmap_update_bits(regs, LPC3XXX_REG_I2S_DAI,
231 					   LPC3XXX_I2S_STOP, LPC3XXX_I2S_STOP);
232 		break;
233 
234 	case SNDRV_PCM_TRIGGER_START:
235 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
236 	case SNDRV_PCM_TRIGGER_RESUME:
237 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
238 			regmap_update_bits(regs, LPC3XXX_REG_I2S_DAO,
239 					   (LPC3XXX_I2S_RESET | LPC3XXX_I2S_STOP), 0);
240 		else
241 			regmap_update_bits(regs, LPC3XXX_REG_I2S_DAI,
242 					   (LPC3XXX_I2S_RESET | LPC3XXX_I2S_STOP), 0);
243 		break;
244 	default:
245 		ret = -EINVAL;
246 	}
247 
248 	return ret;
249 }
250 
251 static int lpc3xxx_i2s_dai_probe(struct snd_soc_dai *dai)
252 {
253 	struct lpc3xxx_i2s_info *i2s_info_p = snd_soc_dai_get_drvdata(dai);
254 
255 	snd_soc_dai_init_dma_data(dai, &i2s_info_p->playback_dma_config,
256 				  &i2s_info_p->capture_dma_config);
257 	return 0;
258 }
259 
260 static const struct snd_soc_dai_ops lpc3xxx_i2s_dai_ops = {
261 	.probe	= lpc3xxx_i2s_dai_probe,
262 	.startup = lpc3xxx_i2s_startup,
263 	.shutdown = lpc3xxx_i2s_shutdown,
264 	.trigger = lpc3xxx_i2s_trigger,
265 	.hw_params = lpc3xxx_i2s_hw_params,
266 	.set_sysclk = lpc3xxx_i2s_set_dai_sysclk,
267 	.set_fmt = lpc3xxx_i2s_set_dai_fmt,
268 };
269 
270 static struct snd_soc_dai_driver lpc3xxx_i2s_dai_driver = {
271 	.playback = {
272 		.channels_min = 1,
273 		.channels_max = 2,
274 		.rates = LPC3XXX_I2S_RATES,
275 		.formats = LPC3XXX_I2S_FORMATS,
276 		},
277 	.capture = {
278 		.channels_min = 1,
279 		.channels_max = 2,
280 		.rates = LPC3XXX_I2S_RATES,
281 		.formats = LPC3XXX_I2S_FORMATS,
282 		},
283 	.ops = &lpc3xxx_i2s_dai_ops,
284 	.symmetric_rate = 1,
285 	.symmetric_channels = 1,
286 	.symmetric_sample_bits = 1,
287 };
288 
289 static const struct snd_soc_component_driver lpc32xx_i2s_component = {
290 	.name = "lpc32xx-i2s",
291 	.legacy_dai_naming = 1,
292 };
293 
294 static const struct regmap_config lpc32xx_i2s_regconfig = {
295 	.reg_bits = 32,
296 	.reg_stride = 4,
297 	.val_bits = 32,
298 	.max_register = LPC3XXX_REG_I2S_RX_RATE,
299 };
300 
301 static int lpc32xx_i2s_probe(struct platform_device *pdev)
302 {
303 	struct device *dev = &pdev->dev;
304 	struct lpc3xxx_i2s_info *i2s_info_p;
305 	struct resource *res;
306 	void __iomem *iomem;
307 	int ret;
308 
309 	i2s_info_p = devm_kzalloc(dev, sizeof(*i2s_info_p), GFP_KERNEL);
310 	if (!i2s_info_p)
311 		return -ENOMEM;
312 
313 	platform_set_drvdata(pdev, i2s_info_p);
314 	i2s_info_p->dev = dev;
315 
316 	iomem = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
317 	if (IS_ERR(iomem))
318 		return dev_err_probe(dev, PTR_ERR(iomem), "Can't map registers\n");
319 
320 	i2s_info_p->regs = devm_regmap_init_mmio(dev, iomem, &lpc32xx_i2s_regconfig);
321 	if (IS_ERR(i2s_info_p->regs))
322 		return dev_err_probe(dev, PTR_ERR(i2s_info_p->regs),
323 				     "failed to init register map: %pe\n", i2s_info_p->regs);
324 
325 	i2s_info_p->clk = devm_clk_get(dev, NULL);
326 	if (IS_ERR(i2s_info_p->clk))
327 		return dev_err_probe(dev, PTR_ERR(i2s_info_p->clk), "Can't get clock\n");
328 
329 	i2s_info_p->clkrate = clk_get_rate(i2s_info_p->clk);
330 	if (i2s_info_p->clkrate == 0)
331 		return dev_err_probe(dev, -EINVAL, "Invalid returned clock rate\n");
332 
333 	mutex_init(&i2s_info_p->lock);
334 
335 	ret = devm_snd_soc_register_component(dev, &lpc32xx_i2s_component,
336 					      &lpc3xxx_i2s_dai_driver, 1);
337 	if (ret)
338 		return dev_err_probe(dev, ret, "Can't register cpu_dai component\n");
339 
340 	i2s_info_p->playback_dma_config.addr = (dma_addr_t)(res->start + LPC3XXX_REG_I2S_TX_FIFO);
341 	i2s_info_p->playback_dma_config.maxburst = 4;
342 
343 	i2s_info_p->capture_dma_config.addr = (dma_addr_t)(res->start + LPC3XXX_REG_I2S_RX_FIFO);
344 	i2s_info_p->capture_dma_config.maxburst = 4;
345 
346 	ret = lpc3xxx_pcm_register(pdev);
347 	if (ret)
348 		return dev_err_probe(dev, ret, "Can't register pcm component\n");
349 
350 	return 0;
351 }
352 
353 static const struct of_device_id lpc32xx_i2s_match[] = {
354 	{ .compatible = "nxp,lpc3220-i2s" },
355 	{},
356 };
357 MODULE_DEVICE_TABLE(of, lpc32xx_i2s_match);
358 
359 static struct platform_driver lpc32xx_i2s_driver = {
360 	.probe = lpc32xx_i2s_probe,
361 	.driver		= {
362 		.name	= "lpc3xxx-i2s",
363 		.of_match_table = lpc32xx_i2s_match,
364 	},
365 };
366 
367 module_platform_driver(lpc32xx_i2s_driver);
368 
369 MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
370 MODULE_AUTHOR("Piotr Wojtaszczyk <piotr.wojtaszczyk@timesys.com>");
371 MODULE_DESCRIPTION("ASoC LPC3XXX I2S interface");
372 MODULE_LICENSE("GPL");
373