xref: /linux/sound/soc/codecs/nau8540.c (revision c748a6d77c06a78651030e17da6beb278a1c9470)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * NAU85L40 ALSA SoC audio driver
4  *
5  * Copyright 2016 Nuvoton Technology Corp.
6  * Author: John Hsu <KCHSU0@nuvoton.com>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/moduleparam.h>
11 #include <linux/init.h>
12 #include <linux/delay.h>
13 #include <linux/pm.h>
14 #include <linux/i2c.h>
15 #include <linux/regmap.h>
16 #include <linux/regulator/consumer.h>
17 #include <linux/spi/spi.h>
18 #include <linux/slab.h>
19 #include <linux/of.h>
20 #include <sound/core.h>
21 #include <sound/pcm.h>
22 #include <sound/pcm_params.h>
23 #include <sound/soc.h>
24 #include <sound/soc-dapm.h>
25 #include <sound/initval.h>
26 #include <sound/tlv.h>
27 #include "nau8540.h"
28 
29 
30 #define NAU_FREF_MAX 13500000
31 #define NAU_FVCO_MAX 100000000
32 #define NAU_FVCO_MIN 90000000
33 
34 /* the maximum frequency of CLK_ADC */
35 #define CLK_ADC_MAX 6144000
36 
37 /* scaling for mclk from sysclk_src output */
38 static const struct nau8540_fll_attr mclk_src_scaling[] = {
39 	{ 1, 0x0 },
40 	{ 2, 0x2 },
41 	{ 4, 0x3 },
42 	{ 8, 0x4 },
43 	{ 16, 0x5 },
44 	{ 32, 0x6 },
45 	{ 3, 0x7 },
46 	{ 6, 0xa },
47 	{ 12, 0xb },
48 	{ 24, 0xc },
49 };
50 
51 /* ratio for input clk freq */
52 static const struct nau8540_fll_attr fll_ratio[] = {
53 	{ 512000, 0x01 },
54 	{ 256000, 0x02 },
55 	{ 128000, 0x04 },
56 	{ 64000, 0x08 },
57 	{ 32000, 0x10 },
58 	{ 8000, 0x20 },
59 	{ 4000, 0x40 },
60 };
61 
62 static const struct nau8540_fll_attr fll_pre_scalar[] = {
63 	{ 1, 0x0 },
64 	{ 2, 0x1 },
65 	{ 4, 0x2 },
66 	{ 8, 0x3 },
67 };
68 
69 /* over sampling rate */
70 static const struct nau8540_osr_attr osr_adc_sel[] = {
71 	{ 32, 3 },	/* OSR 32, SRC 1/8 */
72 	{ 64, 2 },	/* OSR 64, SRC 1/4 */
73 	{ 128, 1 },	/* OSR 128, SRC 1/2 */
74 	{ 256, 0 },	/* OSR 256, SRC 1 */
75 };
76 
77 static const struct reg_default nau8540_reg_defaults[] = {
78 	{NAU8540_REG_POWER_MANAGEMENT, 0x0000},
79 	{NAU8540_REG_CLOCK_CTRL, 0x0000},
80 	{NAU8540_REG_CLOCK_SRC, 0x0000},
81 	{NAU8540_REG_FLL1, 0x0001},
82 	{NAU8540_REG_FLL2, 0x3126},
83 	{NAU8540_REG_FLL3, 0x0008},
84 	{NAU8540_REG_FLL4, 0x0010},
85 	{NAU8540_REG_FLL5, 0xC000},
86 	{NAU8540_REG_FLL6, 0x6000},
87 	{NAU8540_REG_FLL_VCO_RSV, 0xF13C},
88 	{NAU8540_REG_PCM_CTRL0, 0x000B},
89 	{NAU8540_REG_PCM_CTRL1, 0x3010},
90 	{NAU8540_REG_PCM_CTRL2, 0x0800},
91 	{NAU8540_REG_PCM_CTRL3, 0x0000},
92 	{NAU8540_REG_PCM_CTRL4, 0x000F},
93 	{NAU8540_REG_ALC_CONTROL_1, 0x0000},
94 	{NAU8540_REG_ALC_CONTROL_2, 0x700B},
95 	{NAU8540_REG_ALC_CONTROL_3, 0x0022},
96 	{NAU8540_REG_ALC_CONTROL_4, 0x1010},
97 	{NAU8540_REG_ALC_CONTROL_5, 0x1010},
98 	{NAU8540_REG_NOTCH_FIL1_CH1, 0x0000},
99 	{NAU8540_REG_NOTCH_FIL2_CH1, 0x0000},
100 	{NAU8540_REG_NOTCH_FIL1_CH2, 0x0000},
101 	{NAU8540_REG_NOTCH_FIL2_CH2, 0x0000},
102 	{NAU8540_REG_NOTCH_FIL1_CH3, 0x0000},
103 	{NAU8540_REG_NOTCH_FIL2_CH3, 0x0000},
104 	{NAU8540_REG_NOTCH_FIL1_CH4, 0x0000},
105 	{NAU8540_REG_NOTCH_FIL2_CH4, 0x0000},
106 	{NAU8540_REG_HPF_FILTER_CH12, 0x0000},
107 	{NAU8540_REG_HPF_FILTER_CH34, 0x0000},
108 	{NAU8540_REG_ADC_SAMPLE_RATE, 0x0002},
109 	{NAU8540_REG_DIGITAL_GAIN_CH1, 0x0400},
110 	{NAU8540_REG_DIGITAL_GAIN_CH2, 0x0400},
111 	{NAU8540_REG_DIGITAL_GAIN_CH3, 0x0400},
112 	{NAU8540_REG_DIGITAL_GAIN_CH4, 0x0400},
113 	{NAU8540_REG_DIGITAL_MUX, 0x00E4},
114 	{NAU8540_REG_GPIO_CTRL, 0x0000},
115 	{NAU8540_REG_MISC_CTRL, 0x0000},
116 	{NAU8540_REG_I2C_CTRL, 0xEFFF},
117 	{NAU8540_REG_VMID_CTRL, 0x0000},
118 	{NAU8540_REG_MUTE, 0x0000},
119 	{NAU8540_REG_ANALOG_ADC1, 0x0011},
120 	{NAU8540_REG_ANALOG_ADC2, 0x0020},
121 	{NAU8540_REG_ANALOG_PWR, 0x0000},
122 	{NAU8540_REG_MIC_BIAS, 0x0004},
123 	{NAU8540_REG_REFERENCE, 0x0000},
124 	{NAU8540_REG_FEPGA1, 0x0000},
125 	{NAU8540_REG_FEPGA2, 0x0000},
126 	{NAU8540_REG_FEPGA3, 0x0101},
127 	{NAU8540_REG_FEPGA4, 0x0101},
128 	{NAU8540_REG_PWR, 0x0000},
129 };
130 
131 static bool nau8540_readable_reg(struct device *dev, unsigned int reg)
132 {
133 	switch (reg) {
134 	case NAU8540_REG_POWER_MANAGEMENT ... NAU8540_REG_FLL_VCO_RSV:
135 	case NAU8540_REG_PCM_CTRL0 ... NAU8540_REG_PCM_CTRL4:
136 	case NAU8540_REG_ALC_CONTROL_1 ... NAU8540_REG_ALC_CONTROL_5:
137 	case NAU8540_REG_ALC_GAIN_CH12 ... NAU8540_REG_ADC_SAMPLE_RATE:
138 	case NAU8540_REG_DIGITAL_GAIN_CH1 ... NAU8540_REG_DIGITAL_MUX:
139 	case NAU8540_REG_P2P_CH1 ... NAU8540_REG_I2C_CTRL:
140 	case NAU8540_REG_I2C_DEVICE_ID:
141 	case NAU8540_REG_VMID_CTRL ... NAU8540_REG_MUTE:
142 	case NAU8540_REG_ANALOG_ADC1 ... NAU8540_REG_PWR:
143 		return true;
144 	default:
145 		return false;
146 	}
147 
148 }
149 
150 static bool nau8540_writeable_reg(struct device *dev, unsigned int reg)
151 {
152 	switch (reg) {
153 	case NAU8540_REG_SW_RESET ... NAU8540_REG_FLL_VCO_RSV:
154 	case NAU8540_REG_PCM_CTRL0 ... NAU8540_REG_PCM_CTRL4:
155 	case NAU8540_REG_ALC_CONTROL_1 ... NAU8540_REG_ALC_CONTROL_5:
156 	case NAU8540_REG_NOTCH_FIL1_CH1 ... NAU8540_REG_ADC_SAMPLE_RATE:
157 	case NAU8540_REG_DIGITAL_GAIN_CH1 ... NAU8540_REG_DIGITAL_MUX:
158 	case NAU8540_REG_GPIO_CTRL ... NAU8540_REG_I2C_CTRL:
159 	case NAU8540_REG_RST:
160 	case NAU8540_REG_VMID_CTRL ... NAU8540_REG_MUTE:
161 	case NAU8540_REG_ANALOG_ADC1 ... NAU8540_REG_PWR:
162 		return true;
163 	default:
164 		return false;
165 	}
166 }
167 
168 static bool nau8540_volatile_reg(struct device *dev, unsigned int reg)
169 {
170 	switch (reg) {
171 	case NAU8540_REG_SW_RESET:
172 	case NAU8540_REG_ALC_GAIN_CH12 ... NAU8540_REG_ALC_STATUS:
173 	case NAU8540_REG_P2P_CH1 ... NAU8540_REG_PEAK_CH4:
174 	case NAU8540_REG_I2C_DEVICE_ID:
175 	case NAU8540_REG_RST:
176 		return true;
177 	default:
178 		return false;
179 	}
180 }
181 
182 
183 static const DECLARE_TLV_DB_MINMAX(adc_vol_tlv, -12800, 3600);
184 static const DECLARE_TLV_DB_MINMAX(fepga_gain_tlv, -100, 3600);
185 
186 static const struct snd_kcontrol_new nau8540_snd_controls[] = {
187 	SOC_SINGLE_TLV("Mic1 Volume", NAU8540_REG_DIGITAL_GAIN_CH1,
188 		0, 0x520, 0, adc_vol_tlv),
189 	SOC_SINGLE_TLV("Mic2 Volume", NAU8540_REG_DIGITAL_GAIN_CH2,
190 		0, 0x520, 0, adc_vol_tlv),
191 	SOC_SINGLE_TLV("Mic3 Volume", NAU8540_REG_DIGITAL_GAIN_CH3,
192 		0, 0x520, 0, adc_vol_tlv),
193 	SOC_SINGLE_TLV("Mic4 Volume", NAU8540_REG_DIGITAL_GAIN_CH4,
194 		0, 0x520, 0, adc_vol_tlv),
195 
196 	SOC_SINGLE_TLV("Frontend PGA1 Volume", NAU8540_REG_FEPGA3,
197 		0, 0x25, 0, fepga_gain_tlv),
198 	SOC_SINGLE_TLV("Frontend PGA2 Volume", NAU8540_REG_FEPGA3,
199 		8, 0x25, 0, fepga_gain_tlv),
200 	SOC_SINGLE_TLV("Frontend PGA3 Volume", NAU8540_REG_FEPGA4,
201 		0, 0x25, 0, fepga_gain_tlv),
202 	SOC_SINGLE_TLV("Frontend PGA4 Volume", NAU8540_REG_FEPGA4,
203 		8, 0x25, 0, fepga_gain_tlv),
204 };
205 
206 static const char * const adc_channel[] = {
207 	"ADC channel 1", "ADC channel 2", "ADC channel 3", "ADC channel 4"
208 };
209 static SOC_ENUM_SINGLE_DECL(
210 	digital_ch4_enum, NAU8540_REG_DIGITAL_MUX, 6, adc_channel);
211 
212 static const struct snd_kcontrol_new digital_ch4_mux =
213 	SOC_DAPM_ENUM("Digital CH4 Select", digital_ch4_enum);
214 
215 static SOC_ENUM_SINGLE_DECL(
216 	digital_ch3_enum, NAU8540_REG_DIGITAL_MUX, 4, adc_channel);
217 
218 static const struct snd_kcontrol_new digital_ch3_mux =
219 	SOC_DAPM_ENUM("Digital CH3 Select", digital_ch3_enum);
220 
221 static SOC_ENUM_SINGLE_DECL(
222 	digital_ch2_enum, NAU8540_REG_DIGITAL_MUX, 2, adc_channel);
223 
224 static const struct snd_kcontrol_new digital_ch2_mux =
225 	SOC_DAPM_ENUM("Digital CH2 Select", digital_ch2_enum);
226 
227 static SOC_ENUM_SINGLE_DECL(
228 	digital_ch1_enum, NAU8540_REG_DIGITAL_MUX, 0, adc_channel);
229 
230 static const struct snd_kcontrol_new digital_ch1_mux =
231 	SOC_DAPM_ENUM("Digital CH1 Select", digital_ch1_enum);
232 
233 static int adc_power_control(struct snd_soc_dapm_widget *w,
234 		struct snd_kcontrol *k, int  event)
235 {
236 	struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
237 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
238 
239 	if (SND_SOC_DAPM_EVENT_ON(event)) {
240 		msleep(300);
241 		/* DO12 and DO34 pad output enable */
242 		regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL1,
243 			NAU8540_I2S_DO12_TRI, 0);
244 		regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL2,
245 			NAU8540_I2S_DO34_TRI, 0);
246 	} else if (SND_SOC_DAPM_EVENT_OFF(event)) {
247 		regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL1,
248 			NAU8540_I2S_DO12_TRI, NAU8540_I2S_DO12_TRI);
249 		regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL2,
250 			NAU8540_I2S_DO34_TRI, NAU8540_I2S_DO34_TRI);
251 	}
252 	return 0;
253 }
254 
255 static int aiftx_power_control(struct snd_soc_dapm_widget *w,
256 		struct snd_kcontrol *k, int  event)
257 {
258 	struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
259 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
260 
261 	if (SND_SOC_DAPM_EVENT_OFF(event)) {
262 		regmap_write(nau8540->regmap, NAU8540_REG_RST, 0x0001);
263 		regmap_write(nau8540->regmap, NAU8540_REG_RST, 0x0000);
264 	}
265 	return 0;
266 }
267 
268 static const struct snd_soc_dapm_widget nau8540_dapm_widgets[] = {
269 	SND_SOC_DAPM_SUPPLY("MICBIAS2", NAU8540_REG_MIC_BIAS, 11, 0, NULL, 0),
270 	SND_SOC_DAPM_SUPPLY("MICBIAS1", NAU8540_REG_MIC_BIAS, 10, 0, NULL, 0),
271 
272 	SND_SOC_DAPM_INPUT("MIC1"),
273 	SND_SOC_DAPM_INPUT("MIC2"),
274 	SND_SOC_DAPM_INPUT("MIC3"),
275 	SND_SOC_DAPM_INPUT("MIC4"),
276 
277 	SND_SOC_DAPM_PGA("Frontend PGA1", NAU8540_REG_PWR, 12, 0, NULL, 0),
278 	SND_SOC_DAPM_PGA("Frontend PGA2", NAU8540_REG_PWR, 13, 0, NULL, 0),
279 	SND_SOC_DAPM_PGA("Frontend PGA3", NAU8540_REG_PWR, 14, 0, NULL, 0),
280 	SND_SOC_DAPM_PGA("Frontend PGA4", NAU8540_REG_PWR, 15, 0, NULL, 0),
281 
282 	SND_SOC_DAPM_ADC_E("ADC1", NULL,
283 		NAU8540_REG_POWER_MANAGEMENT, 0, 0, adc_power_control,
284 		SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
285 	SND_SOC_DAPM_ADC_E("ADC2", NULL,
286 		NAU8540_REG_POWER_MANAGEMENT, 1, 0, adc_power_control,
287 		SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
288 	SND_SOC_DAPM_ADC_E("ADC3", NULL,
289 		NAU8540_REG_POWER_MANAGEMENT, 2, 0, adc_power_control,
290 		SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
291 	SND_SOC_DAPM_ADC_E("ADC4", NULL,
292 		NAU8540_REG_POWER_MANAGEMENT, 3, 0, adc_power_control,
293 		SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
294 
295 	SND_SOC_DAPM_PGA("ADC CH1", NAU8540_REG_ANALOG_PWR, 0, 0, NULL, 0),
296 	SND_SOC_DAPM_PGA("ADC CH2", NAU8540_REG_ANALOG_PWR, 1, 0, NULL, 0),
297 	SND_SOC_DAPM_PGA("ADC CH3", NAU8540_REG_ANALOG_PWR, 2, 0, NULL, 0),
298 	SND_SOC_DAPM_PGA("ADC CH4", NAU8540_REG_ANALOG_PWR, 3, 0, NULL, 0),
299 
300 	SND_SOC_DAPM_MUX("Digital CH4 Mux",
301 		SND_SOC_NOPM, 0, 0, &digital_ch4_mux),
302 	SND_SOC_DAPM_MUX("Digital CH3 Mux",
303 		SND_SOC_NOPM, 0, 0, &digital_ch3_mux),
304 	SND_SOC_DAPM_MUX("Digital CH2 Mux",
305 		SND_SOC_NOPM, 0, 0, &digital_ch2_mux),
306 	SND_SOC_DAPM_MUX("Digital CH1 Mux",
307 		SND_SOC_NOPM, 0, 0, &digital_ch1_mux),
308 
309 	SND_SOC_DAPM_AIF_OUT_E("AIFTX", "Capture", 0, SND_SOC_NOPM, 0, 0,
310 		aiftx_power_control, SND_SOC_DAPM_POST_PMD),
311 };
312 
313 static const struct snd_soc_dapm_route nau8540_dapm_routes[] = {
314 	{"Frontend PGA1", NULL, "MIC1"},
315 	{"Frontend PGA2", NULL, "MIC2"},
316 	{"Frontend PGA3", NULL, "MIC3"},
317 	{"Frontend PGA4", NULL, "MIC4"},
318 
319 	{"ADC1", NULL, "Frontend PGA1"},
320 	{"ADC2", NULL, "Frontend PGA2"},
321 	{"ADC3", NULL, "Frontend PGA3"},
322 	{"ADC4", NULL, "Frontend PGA4"},
323 
324 	{"ADC CH1", NULL, "ADC1"},
325 	{"ADC CH2", NULL, "ADC2"},
326 	{"ADC CH3", NULL, "ADC3"},
327 	{"ADC CH4", NULL, "ADC4"},
328 
329 	{"ADC1", NULL, "MICBIAS1"},
330 	{"ADC2", NULL, "MICBIAS1"},
331 	{"ADC3", NULL, "MICBIAS2"},
332 	{"ADC4", NULL, "MICBIAS2"},
333 
334 	{"Digital CH1 Mux", "ADC channel 1", "ADC CH1"},
335 	{"Digital CH1 Mux", "ADC channel 2", "ADC CH2"},
336 	{"Digital CH1 Mux", "ADC channel 3", "ADC CH3"},
337 	{"Digital CH1 Mux", "ADC channel 4", "ADC CH4"},
338 
339 	{"Digital CH2 Mux", "ADC channel 1", "ADC CH1"},
340 	{"Digital CH2 Mux", "ADC channel 2", "ADC CH2"},
341 	{"Digital CH2 Mux", "ADC channel 3", "ADC CH3"},
342 	{"Digital CH2 Mux", "ADC channel 4", "ADC CH4"},
343 
344 	{"Digital CH3 Mux", "ADC channel 1", "ADC CH1"},
345 	{"Digital CH3 Mux", "ADC channel 2", "ADC CH2"},
346 	{"Digital CH3 Mux", "ADC channel 3", "ADC CH3"},
347 	{"Digital CH3 Mux", "ADC channel 4", "ADC CH4"},
348 
349 	{"Digital CH4 Mux", "ADC channel 1", "ADC CH1"},
350 	{"Digital CH4 Mux", "ADC channel 2", "ADC CH2"},
351 	{"Digital CH4 Mux", "ADC channel 3", "ADC CH3"},
352 	{"Digital CH4 Mux", "ADC channel 4", "ADC CH4"},
353 
354 	{"AIFTX", NULL, "Digital CH1 Mux"},
355 	{"AIFTX", NULL, "Digital CH2 Mux"},
356 	{"AIFTX", NULL, "Digital CH3 Mux"},
357 	{"AIFTX", NULL, "Digital CH4 Mux"},
358 };
359 
360 static const struct nau8540_osr_attr *
361 nau8540_get_osr(struct nau8540 *nau8540)
362 {
363 	unsigned int osr;
364 
365 	regmap_read(nau8540->regmap, NAU8540_REG_ADC_SAMPLE_RATE, &osr);
366 	osr &= NAU8540_ADC_OSR_MASK;
367 	if (osr >= ARRAY_SIZE(osr_adc_sel))
368 		return NULL;
369 	return &osr_adc_sel[osr];
370 }
371 
372 static int nau8540_dai_startup(struct snd_pcm_substream *substream,
373 			       struct snd_soc_dai *dai)
374 {
375 	struct snd_soc_component *component = dai->component;
376 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
377 	const struct nau8540_osr_attr *osr;
378 
379 	osr = nau8540_get_osr(nau8540);
380 	if (!osr || !osr->osr)
381 		return -EINVAL;
382 
383 	return snd_pcm_hw_constraint_minmax(substream->runtime,
384 					    SNDRV_PCM_HW_PARAM_RATE,
385 					    0, CLK_ADC_MAX / osr->osr);
386 }
387 
388 static int nau8540_hw_params(struct snd_pcm_substream *substream,
389 	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
390 {
391 	struct snd_soc_component *component = dai->component;
392 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
393 	unsigned int val_len = 0;
394 	const struct nau8540_osr_attr *osr;
395 
396 	/* CLK_ADC = OSR * FS
397 	 * ADC clock frequency is defined as Over Sampling Rate (OSR)
398 	 * multiplied by the audio sample rate (Fs). Note that the OSR and Fs
399 	 * values must be selected such that the maximum frequency is less
400 	 * than 6.144 MHz.
401 	 */
402 	osr = nau8540_get_osr(nau8540);
403 	if (!osr || !osr->osr)
404 		return -EINVAL;
405 	if (params_rate(params) * osr->osr > CLK_ADC_MAX)
406 		return -EINVAL;
407 	regmap_update_bits(nau8540->regmap, NAU8540_REG_CLOCK_SRC,
408 		NAU8540_CLK_ADC_SRC_MASK,
409 		osr->clk_src << NAU8540_CLK_ADC_SRC_SFT);
410 
411 	switch (params_width(params)) {
412 	case 16:
413 		val_len |= NAU8540_I2S_DL_16;
414 		break;
415 	case 20:
416 		val_len |= NAU8540_I2S_DL_20;
417 		break;
418 	case 24:
419 		val_len |= NAU8540_I2S_DL_24;
420 		break;
421 	case 32:
422 		val_len |= NAU8540_I2S_DL_32;
423 		break;
424 	default:
425 		return -EINVAL;
426 	}
427 
428 	regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL0,
429 		NAU8540_I2S_DL_MASK, val_len);
430 
431 	return 0;
432 }
433 
434 static int nau8540_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
435 {
436 	struct snd_soc_component *component = dai->component;
437 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
438 	unsigned int ctrl1_val = 0, ctrl2_val = 0;
439 
440 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
441 	case SND_SOC_DAIFMT_CBM_CFM:
442 		ctrl2_val |= NAU8540_I2S_MS_MASTER;
443 		break;
444 	case SND_SOC_DAIFMT_CBS_CFS:
445 		break;
446 	default:
447 		return -EINVAL;
448 	}
449 
450 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
451 	case SND_SOC_DAIFMT_NB_NF:
452 		break;
453 	case SND_SOC_DAIFMT_IB_NF:
454 		ctrl1_val |= NAU8540_I2S_BP_INV;
455 		break;
456 	default:
457 		return -EINVAL;
458 	}
459 
460 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
461 	case SND_SOC_DAIFMT_I2S:
462 		ctrl1_val |= NAU8540_I2S_DF_I2S;
463 		break;
464 	case SND_SOC_DAIFMT_LEFT_J:
465 		ctrl1_val |= NAU8540_I2S_DF_LEFT;
466 		break;
467 	case SND_SOC_DAIFMT_RIGHT_J:
468 		ctrl1_val |= NAU8540_I2S_DF_RIGTH;
469 		break;
470 	case SND_SOC_DAIFMT_DSP_A:
471 		ctrl1_val |= NAU8540_I2S_DF_PCM_AB;
472 		break;
473 	case SND_SOC_DAIFMT_DSP_B:
474 		ctrl1_val |= NAU8540_I2S_DF_PCM_AB;
475 		ctrl1_val |= NAU8540_I2S_PCMB_EN;
476 		break;
477 	default:
478 		return -EINVAL;
479 	}
480 
481 	regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL0,
482 		NAU8540_I2S_DL_MASK | NAU8540_I2S_DF_MASK |
483 		NAU8540_I2S_BP_INV | NAU8540_I2S_PCMB_EN, ctrl1_val);
484 	regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL1,
485 		NAU8540_I2S_MS_MASK | NAU8540_I2S_DO12_OE, ctrl2_val);
486 	regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL2,
487 		NAU8540_I2S_DO34_OE, 0);
488 
489 	return 0;
490 }
491 
492 /**
493  * nau8540_set_tdm_slot - configure DAI TX TDM.
494  * @dai: DAI
495  * @tx_mask: bitmask representing active TX slots. Ex.
496  *                 0xf for normal 4 channel TDM.
497  *                 0xf0 for shifted 4 channel TDM
498  * @rx_mask: no used.
499  * @slots: Number of slots in use.
500  * @slot_width: Width in bits for each slot.
501  *
502  * Configures a DAI for TDM operation. Only support 4 slots TDM.
503  */
504 static int nau8540_set_tdm_slot(struct snd_soc_dai *dai,
505 	unsigned int tx_mask, unsigned int rx_mask, int slots, int slot_width)
506 {
507 	struct snd_soc_component *component = dai->component;
508 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
509 	unsigned int ctrl2_val = 0, ctrl4_val = 0;
510 
511 	if (slots > 4 || ((tx_mask & 0xf0) && (tx_mask & 0xf)))
512 		return -EINVAL;
513 
514 	ctrl4_val |= (NAU8540_TDM_MODE | NAU8540_TDM_OFFSET_EN);
515 	if (tx_mask & 0xf0) {
516 		ctrl2_val = 4 * slot_width;
517 		ctrl4_val |= (tx_mask >> 4);
518 	} else {
519 		ctrl4_val |= tx_mask;
520 	}
521 	regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL4,
522 		NAU8540_TDM_MODE | NAU8540_TDM_OFFSET_EN |
523 		NAU8540_TDM_TX_MASK, ctrl4_val);
524 	regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL1,
525 		NAU8540_I2S_DO12_OE, NAU8540_I2S_DO12_OE);
526 	regmap_update_bits(nau8540->regmap, NAU8540_REG_PCM_CTRL2,
527 		NAU8540_I2S_DO34_OE | NAU8540_I2S_TSLOT_L_MASK,
528 		NAU8540_I2S_DO34_OE | ctrl2_val);
529 
530 	return 0;
531 }
532 
533 static int nau8540_dai_trigger(struct snd_pcm_substream *substream,
534 			       int cmd, struct snd_soc_dai *dai)
535 {
536 	struct snd_soc_component *component = dai->component;
537 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
538 	struct regmap *regmap = nau8540->regmap;
539 	unsigned int val;
540 	int ret = 0;
541 
542 	/* Reading the peak data to detect abnormal data in the ADC channel.
543 	 * If abnormal data happens, the driver takes recovery actions to
544 	 * refresh the ADC channel.
545 	 */
546 	switch (cmd) {
547 	case SNDRV_PCM_TRIGGER_START:
548 		regmap_update_bits(regmap, NAU8540_REG_CLOCK_CTRL,
549 				   NAU8540_CLK_AGC_EN, NAU8540_CLK_AGC_EN);
550 		regmap_update_bits(regmap, NAU8540_REG_ALC_CONTROL_3,
551 				   NAU8540_ALC_CH_ALL_EN, NAU8540_ALC_CH_ALL_EN);
552 
553 		regmap_read(regmap, NAU8540_REG_PEAK_CH1, &val);
554 		dev_dbg(nau8540->dev, "1.ADC CH1 peak data %x", val);
555 		if (!val) {
556 			regmap_update_bits(regmap, NAU8540_REG_MUTE,
557 					   NAU8540_PGA_CH_ALL_MUTE, NAU8540_PGA_CH_ALL_MUTE);
558 			regmap_update_bits(regmap, NAU8540_REG_MUTE,
559 					   NAU8540_PGA_CH_ALL_MUTE, 0);
560 			regmap_write(regmap, NAU8540_REG_RST, 0x1);
561 			regmap_write(regmap, NAU8540_REG_RST, 0);
562 			regmap_read(regmap, NAU8540_REG_PEAK_CH1, &val);
563 			dev_dbg(nau8540->dev, "2.ADC CH1 peak data %x", val);
564 			if (!val) {
565 				dev_err(nau8540->dev, "Channel recovery failed!!");
566 				ret = -EIO;
567 			}
568 		}
569 		regmap_update_bits(regmap, NAU8540_REG_CLOCK_CTRL,
570 				   NAU8540_CLK_AGC_EN, 0);
571 		regmap_update_bits(regmap, NAU8540_REG_ALC_CONTROL_3,
572 				   NAU8540_ALC_CH_ALL_EN, 0);
573 		break;
574 
575 	default:
576 		break;
577 	}
578 
579 	return ret;
580 }
581 
582 static const struct snd_soc_dai_ops nau8540_dai_ops = {
583 	.startup = nau8540_dai_startup,
584 	.hw_params = nau8540_hw_params,
585 	.set_fmt = nau8540_set_fmt,
586 	.set_tdm_slot = nau8540_set_tdm_slot,
587 	.trigger = nau8540_dai_trigger,
588 };
589 
590 #define NAU8540_RATES SNDRV_PCM_RATE_8000_48000
591 #define NAU8540_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE \
592 	 | SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S32_LE)
593 
594 static struct snd_soc_dai_driver nau8540_dai = {
595 	.name = "nau8540-hifi",
596 	.capture = {
597 		.stream_name = "Capture",
598 		.channels_min = 1,
599 		.channels_max = 4,
600 		.rates = NAU8540_RATES,
601 		.formats = NAU8540_FORMATS,
602 	},
603 	.ops = &nau8540_dai_ops,
604 };
605 
606 /**
607  * nau8540_calc_fll_param - Calculate FLL parameters.
608  * @fll_in: external clock provided to codec.
609  * @fs: sampling rate.
610  * @fll_param: Pointer to structure of FLL parameters.
611  *
612  * Calculate FLL parameters to configure codec.
613  *
614  * Returns 0 for success or negative error code.
615  */
616 static int nau8540_calc_fll_param(unsigned int fll_in,
617 	unsigned int fs, struct nau8540_fll *fll_param)
618 {
619 	u64 fvco, fvco_max;
620 	unsigned int fref, i, fvco_sel;
621 
622 	/* Ensure the reference clock frequency (FREF) is <= 13.5MHz by dividing
623 	 * freq_in by 1, 2, 4, or 8 using FLL pre-scalar.
624 	 * FREF = freq_in / NAU8540_FLL_REF_DIV_MASK
625 	 */
626 	for (i = 0; i < ARRAY_SIZE(fll_pre_scalar); i++) {
627 		fref = fll_in / fll_pre_scalar[i].param;
628 		if (fref <= NAU_FREF_MAX)
629 			break;
630 	}
631 	if (i == ARRAY_SIZE(fll_pre_scalar))
632 		return -EINVAL;
633 	fll_param->clk_ref_div = fll_pre_scalar[i].val;
634 
635 	/* Choose the FLL ratio based on FREF */
636 	for (i = 0; i < ARRAY_SIZE(fll_ratio); i++) {
637 		if (fref >= fll_ratio[i].param)
638 			break;
639 	}
640 	if (i == ARRAY_SIZE(fll_ratio))
641 		return -EINVAL;
642 	fll_param->ratio = fll_ratio[i].val;
643 
644 	/* Calculate the frequency of DCO (FDCO) given freq_out = 256 * Fs.
645 	 * FDCO must be within the 90MHz - 124MHz or the FFL cannot be
646 	 * guaranteed across the full range of operation.
647 	 * FDCO = freq_out * 2 * mclk_src_scaling
648 	 */
649 	fvco_max = 0;
650 	fvco_sel = ARRAY_SIZE(mclk_src_scaling);
651 	for (i = 0; i < ARRAY_SIZE(mclk_src_scaling); i++) {
652 		fvco = 256ULL * fs * 2 * mclk_src_scaling[i].param;
653 		if (fvco > NAU_FVCO_MIN && fvco < NAU_FVCO_MAX &&
654 			fvco_max < fvco) {
655 			fvco_max = fvco;
656 			fvco_sel = i;
657 		}
658 	}
659 	if (ARRAY_SIZE(mclk_src_scaling) == fvco_sel)
660 		return -EINVAL;
661 	fll_param->mclk_src = mclk_src_scaling[fvco_sel].val;
662 
663 	/* Calculate the FLL 10-bit integer input and the FLL 16-bit fractional
664 	 * input based on FDCO, FREF and FLL ratio.
665 	 */
666 	fvco = div_u64(fvco_max << 16, fref * fll_param->ratio);
667 	fll_param->fll_int = (fvco >> 16) & 0x3FF;
668 	fll_param->fll_frac = fvco & 0xFFFF;
669 	return 0;
670 }
671 
672 static void nau8540_fll_apply(struct regmap *regmap,
673 	struct nau8540_fll *fll_param)
674 {
675 	regmap_update_bits(regmap, NAU8540_REG_CLOCK_SRC,
676 		NAU8540_CLK_SRC_MASK | NAU8540_CLK_MCLK_SRC_MASK,
677 		NAU8540_CLK_SRC_MCLK | fll_param->mclk_src);
678 	regmap_update_bits(regmap, NAU8540_REG_FLL1,
679 		NAU8540_FLL_RATIO_MASK | NAU8540_ICTRL_LATCH_MASK,
680 		fll_param->ratio | (0x6 << NAU8540_ICTRL_LATCH_SFT));
681 	/* FLL 16-bit fractional input */
682 	regmap_write(regmap, NAU8540_REG_FLL2, fll_param->fll_frac);
683 	/* FLL 10-bit integer input */
684 	regmap_update_bits(regmap, NAU8540_REG_FLL3,
685 		NAU8540_FLL_INTEGER_MASK, fll_param->fll_int);
686 	/* FLL pre-scaler */
687 	regmap_update_bits(regmap, NAU8540_REG_FLL4,
688 		NAU8540_FLL_REF_DIV_MASK,
689 		fll_param->clk_ref_div << NAU8540_FLL_REF_DIV_SFT);
690 	regmap_update_bits(regmap, NAU8540_REG_FLL5,
691 		NAU8540_FLL_CLK_SW_MASK, NAU8540_FLL_CLK_SW_REF);
692 	regmap_update_bits(regmap,
693 		NAU8540_REG_FLL6, NAU8540_DCO_EN, 0);
694 	if (fll_param->fll_frac) {
695 		regmap_update_bits(regmap, NAU8540_REG_FLL5,
696 			NAU8540_FLL_PDB_DAC_EN | NAU8540_FLL_LOOP_FTR_EN |
697 			NAU8540_FLL_FTR_SW_MASK,
698 			NAU8540_FLL_PDB_DAC_EN | NAU8540_FLL_LOOP_FTR_EN |
699 			NAU8540_FLL_FTR_SW_FILTER);
700 		regmap_update_bits(regmap, NAU8540_REG_FLL6,
701 			NAU8540_SDM_EN | NAU8540_CUTOFF500,
702 			NAU8540_SDM_EN | NAU8540_CUTOFF500);
703 	} else {
704 		regmap_update_bits(regmap, NAU8540_REG_FLL5,
705 			NAU8540_FLL_PDB_DAC_EN | NAU8540_FLL_LOOP_FTR_EN |
706 			NAU8540_FLL_FTR_SW_MASK, NAU8540_FLL_FTR_SW_ACCU);
707 		regmap_update_bits(regmap, NAU8540_REG_FLL6,
708 			NAU8540_SDM_EN | NAU8540_CUTOFF500, 0);
709 	}
710 }
711 
712 /* freq_out must be 256*Fs in order to achieve the best performance */
713 static int nau8540_set_pll(struct snd_soc_component *component, int pll_id, int source,
714 		unsigned int freq_in, unsigned int freq_out)
715 {
716 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
717 	struct nau8540_fll fll_param;
718 	int ret, fs;
719 
720 	switch (pll_id) {
721 	case NAU8540_CLK_FLL_MCLK:
722 		regmap_update_bits(nau8540->regmap, NAU8540_REG_FLL3,
723 			NAU8540_FLL_CLK_SRC_MASK | NAU8540_GAIN_ERR_MASK,
724 			NAU8540_FLL_CLK_SRC_MCLK | 0);
725 		break;
726 
727 	case NAU8540_CLK_FLL_BLK:
728 		regmap_update_bits(nau8540->regmap, NAU8540_REG_FLL3,
729 			NAU8540_FLL_CLK_SRC_MASK | NAU8540_GAIN_ERR_MASK,
730 			NAU8540_FLL_CLK_SRC_BLK |
731 			(0xf << NAU8540_GAIN_ERR_SFT));
732 		break;
733 
734 	case NAU8540_CLK_FLL_FS:
735 		regmap_update_bits(nau8540->regmap, NAU8540_REG_FLL3,
736 			NAU8540_FLL_CLK_SRC_MASK | NAU8540_GAIN_ERR_MASK,
737 			NAU8540_FLL_CLK_SRC_FS |
738 			(0xf << NAU8540_GAIN_ERR_SFT));
739 		break;
740 
741 	default:
742 		dev_err(nau8540->dev, "Invalid clock id (%d)\n", pll_id);
743 		return -EINVAL;
744 	}
745 	dev_dbg(nau8540->dev, "Sysclk is %dHz and clock id is %d\n",
746 		freq_out, pll_id);
747 
748 	fs = freq_out / 256;
749 	ret = nau8540_calc_fll_param(freq_in, fs, &fll_param);
750 	if (ret < 0) {
751 		dev_err(nau8540->dev, "Unsupported input clock %d\n", freq_in);
752 		return ret;
753 	}
754 	dev_dbg(nau8540->dev, "mclk_src=%x ratio=%x fll_frac=%x fll_int=%x clk_ref_div=%x\n",
755 		fll_param.mclk_src, fll_param.ratio, fll_param.fll_frac,
756 		fll_param.fll_int, fll_param.clk_ref_div);
757 
758 	nau8540_fll_apply(nau8540->regmap, &fll_param);
759 	mdelay(2);
760 	regmap_update_bits(nau8540->regmap, NAU8540_REG_CLOCK_SRC,
761 		NAU8540_CLK_SRC_MASK, NAU8540_CLK_SRC_VCO);
762 
763 	return 0;
764 }
765 
766 static int nau8540_set_sysclk(struct snd_soc_component *component,
767 	int clk_id, int source, unsigned int freq, int dir)
768 {
769 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
770 
771 	switch (clk_id) {
772 	case NAU8540_CLK_DIS:
773 	case NAU8540_CLK_MCLK:
774 		regmap_update_bits(nau8540->regmap, NAU8540_REG_CLOCK_SRC,
775 			NAU8540_CLK_SRC_MASK, NAU8540_CLK_SRC_MCLK);
776 		regmap_update_bits(nau8540->regmap, NAU8540_REG_FLL6,
777 			NAU8540_DCO_EN, 0);
778 		break;
779 
780 	case NAU8540_CLK_INTERNAL:
781 		regmap_update_bits(nau8540->regmap, NAU8540_REG_FLL6,
782 			NAU8540_DCO_EN, NAU8540_DCO_EN);
783 		regmap_update_bits(nau8540->regmap, NAU8540_REG_CLOCK_SRC,
784 			NAU8540_CLK_SRC_MASK, NAU8540_CLK_SRC_VCO);
785 		break;
786 
787 	default:
788 		dev_err(nau8540->dev, "Invalid clock id (%d)\n", clk_id);
789 		return -EINVAL;
790 	}
791 
792 	dev_dbg(nau8540->dev, "Sysclk is %dHz and clock id is %d\n",
793 		freq, clk_id);
794 
795 	return 0;
796 }
797 
798 static void nau8540_reset_chip(struct regmap *regmap)
799 {
800 	regmap_write(regmap, NAU8540_REG_SW_RESET, 0x00);
801 	regmap_write(regmap, NAU8540_REG_SW_RESET, 0x00);
802 }
803 
804 static void nau8540_init_regs(struct nau8540 *nau8540)
805 {
806 	struct regmap *regmap = nau8540->regmap;
807 
808 	/* Enable Bias/VMID/VMID Tieoff */
809 	regmap_update_bits(regmap, NAU8540_REG_VMID_CTRL,
810 		NAU8540_VMID_EN | NAU8540_VMID_SEL_MASK,
811 		NAU8540_VMID_EN | (0x2 << NAU8540_VMID_SEL_SFT));
812 	regmap_update_bits(regmap, NAU8540_REG_REFERENCE,
813 		NAU8540_PRECHARGE_DIS | NAU8540_GLOBAL_BIAS_EN,
814 		NAU8540_PRECHARGE_DIS | NAU8540_GLOBAL_BIAS_EN);
815 	mdelay(2);
816 	regmap_update_bits(regmap, NAU8540_REG_MIC_BIAS,
817 		NAU8540_PU_PRE, NAU8540_PU_PRE);
818 	regmap_update_bits(regmap, NAU8540_REG_CLOCK_CTRL,
819 		NAU8540_CLK_ADC_EN | NAU8540_CLK_I2S_EN,
820 		NAU8540_CLK_ADC_EN | NAU8540_CLK_I2S_EN);
821 	/* ADC OSR selection, CLK_ADC = Fs * OSR;
822 	 * Channel time alignment enable.
823 	 */
824 	regmap_update_bits(regmap, NAU8540_REG_ADC_SAMPLE_RATE,
825 		NAU8540_CH_SYNC | NAU8540_ADC_OSR_MASK,
826 		NAU8540_CH_SYNC | NAU8540_ADC_OSR_64);
827 	/* PGA input mode selection */
828 	regmap_update_bits(regmap, NAU8540_REG_FEPGA1,
829 		NAU8540_FEPGA1_MODCH2_SHT | NAU8540_FEPGA1_MODCH1_SHT,
830 		NAU8540_FEPGA1_MODCH2_SHT | NAU8540_FEPGA1_MODCH1_SHT);
831 	regmap_update_bits(regmap, NAU8540_REG_FEPGA2,
832 		NAU8540_FEPGA2_MODCH4_SHT | NAU8540_FEPGA2_MODCH3_SHT,
833 		NAU8540_FEPGA2_MODCH4_SHT | NAU8540_FEPGA2_MODCH3_SHT);
834 	/* DO12 and DO34 pad output disable */
835 	regmap_update_bits(regmap, NAU8540_REG_PCM_CTRL1,
836 		NAU8540_I2S_DO12_TRI, NAU8540_I2S_DO12_TRI);
837 	regmap_update_bits(regmap, NAU8540_REG_PCM_CTRL2,
838 		NAU8540_I2S_DO34_TRI, NAU8540_I2S_DO34_TRI);
839 }
840 
841 static int __maybe_unused nau8540_suspend(struct snd_soc_component *component)
842 {
843 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
844 
845 	regcache_cache_only(nau8540->regmap, true);
846 	regcache_mark_dirty(nau8540->regmap);
847 
848 	return 0;
849 }
850 
851 static int __maybe_unused nau8540_resume(struct snd_soc_component *component)
852 {
853 	struct nau8540 *nau8540 = snd_soc_component_get_drvdata(component);
854 
855 	regcache_cache_only(nau8540->regmap, false);
856 	regcache_sync(nau8540->regmap);
857 
858 	return 0;
859 }
860 
861 static const struct snd_soc_component_driver nau8540_component_driver = {
862 	.set_sysclk		= nau8540_set_sysclk,
863 	.set_pll		= nau8540_set_pll,
864 	.suspend		= nau8540_suspend,
865 	.resume			= nau8540_resume,
866 	.controls		= nau8540_snd_controls,
867 	.num_controls		= ARRAY_SIZE(nau8540_snd_controls),
868 	.dapm_widgets		= nau8540_dapm_widgets,
869 	.num_dapm_widgets	= ARRAY_SIZE(nau8540_dapm_widgets),
870 	.dapm_routes		= nau8540_dapm_routes,
871 	.num_dapm_routes	= ARRAY_SIZE(nau8540_dapm_routes),
872 	.suspend_bias_off	= 1,
873 	.idle_bias_on		= 1,
874 	.use_pmdown_time	= 1,
875 	.endianness		= 1,
876 };
877 
878 static const struct regmap_config nau8540_regmap_config = {
879 	.val_bits = 16,
880 	.reg_bits = 16,
881 
882 	.max_register = NAU8540_REG_MAX,
883 	.readable_reg = nau8540_readable_reg,
884 	.writeable_reg = nau8540_writeable_reg,
885 	.volatile_reg = nau8540_volatile_reg,
886 
887 	.cache_type = REGCACHE_RBTREE,
888 	.reg_defaults = nau8540_reg_defaults,
889 	.num_reg_defaults = ARRAY_SIZE(nau8540_reg_defaults),
890 };
891 
892 static int nau8540_i2c_probe(struct i2c_client *i2c)
893 {
894 	struct device *dev = &i2c->dev;
895 	struct nau8540 *nau8540 = dev_get_platdata(dev);
896 	int ret, value;
897 
898 	if (!nau8540) {
899 		nau8540 = devm_kzalloc(dev, sizeof(*nau8540), GFP_KERNEL);
900 		if (!nau8540)
901 			return -ENOMEM;
902 	}
903 	i2c_set_clientdata(i2c, nau8540);
904 
905 	nau8540->regmap = devm_regmap_init_i2c(i2c, &nau8540_regmap_config);
906 	if (IS_ERR(nau8540->regmap))
907 		return PTR_ERR(nau8540->regmap);
908 	ret = regmap_read(nau8540->regmap, NAU8540_REG_I2C_DEVICE_ID, &value);
909 	if (ret < 0) {
910 		dev_err(dev, "Failed to read device id from the NAU85L40: %d\n",
911 			ret);
912 		return ret;
913 	}
914 
915 	nau8540->dev = dev;
916 	nau8540_reset_chip(nau8540->regmap);
917 	nau8540_init_regs(nau8540);
918 
919 	return devm_snd_soc_register_component(dev,
920 		&nau8540_component_driver, &nau8540_dai, 1);
921 }
922 
923 static const struct i2c_device_id nau8540_i2c_ids[] = {
924 	{ "nau8540", 0 },
925 	{ }
926 };
927 MODULE_DEVICE_TABLE(i2c, nau8540_i2c_ids);
928 
929 #ifdef CONFIG_OF
930 static const struct of_device_id nau8540_of_ids[] = {
931 	{ .compatible = "nuvoton,nau8540", },
932 	{}
933 };
934 MODULE_DEVICE_TABLE(of, nau8540_of_ids);
935 #endif
936 
937 static struct i2c_driver nau8540_i2c_driver = {
938 	.driver = {
939 		.name = "nau8540",
940 		.of_match_table = of_match_ptr(nau8540_of_ids),
941 	},
942 	.probe = nau8540_i2c_probe,
943 	.id_table = nau8540_i2c_ids,
944 };
945 module_i2c_driver(nau8540_i2c_driver);
946 
947 MODULE_DESCRIPTION("ASoC NAU85L40 driver");
948 MODULE_AUTHOR("John Hsu <KCHSU0@nuvoton.com>");
949 MODULE_LICENSE("GPL v2");
950