xref: /linux/sound/soc/codecs/wm8978.c (revision 962fad301c33dec69324dc2d9320fd84a119a24c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * wm8978.c  --  WM8978 ALSA SoC Audio Codec driver
4  *
5  * Copyright (C) 2009-2010 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
6  * Copyright (C) 2007 Carlos Munoz <carlos@kenati.com>
7  * Copyright 2006-2009 Wolfson Microelectronics PLC.
8  * Based on wm8974 and wm8990 by Liam Girdwood <lrg@slimlogic.co.uk>
9  */
10 
11 #include <linux/module.h>
12 #include <linux/moduleparam.h>
13 #include <linux/kernel.h>
14 #include <linux/init.h>
15 #include <linux/delay.h>
16 #include <linux/pm.h>
17 #include <linux/i2c.h>
18 #include <linux/regmap.h>
19 #include <linux/slab.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/initval.h>
25 #include <sound/tlv.h>
26 #include <asm/div64.h>
27 
28 #include "wm8978.h"
29 
30 static const struct reg_default wm8978_reg_defaults[] = {
31 	{ 1, 0x0000 },
32 	{ 2, 0x0000 },
33 	{ 3, 0x0000 },
34 	{ 4, 0x0050 },
35 	{ 5, 0x0000 },
36 	{ 6, 0x0140 },
37 	{ 7, 0x0000 },
38 	{ 8, 0x0000 },
39 	{ 9, 0x0000 },
40 	{ 10, 0x0000 },
41 	{ 11, 0x00ff },
42 	{ 12, 0x00ff },
43 	{ 13, 0x0000 },
44 	{ 14, 0x0100 },
45 	{ 15, 0x00ff },
46 	{ 16, 0x00ff },
47 	{ 17, 0x0000 },
48 	{ 18, 0x012c },
49 	{ 19, 0x002c },
50 	{ 20, 0x002c },
51 	{ 21, 0x002c },
52 	{ 22, 0x002c },
53 	{ 23, 0x0000 },
54 	{ 24, 0x0032 },
55 	{ 25, 0x0000 },
56 	{ 26, 0x0000 },
57 	{ 27, 0x0000 },
58 	{ 28, 0x0000 },
59 	{ 29, 0x0000 },
60 	{ 30, 0x0000 },
61 	{ 31, 0x0000 },
62 	{ 32, 0x0038 },
63 	{ 33, 0x000b },
64 	{ 34, 0x0032 },
65 	{ 35, 0x0000 },
66 	{ 36, 0x0008 },
67 	{ 37, 0x000c },
68 	{ 38, 0x0093 },
69 	{ 39, 0x00e9 },
70 	{ 40, 0x0000 },
71 	{ 41, 0x0000 },
72 	{ 42, 0x0000 },
73 	{ 43, 0x0000 },
74 	{ 44, 0x0033 },
75 	{ 45, 0x0010 },
76 	{ 46, 0x0010 },
77 	{ 47, 0x0100 },
78 	{ 48, 0x0100 },
79 	{ 49, 0x0002 },
80 	{ 50, 0x0001 },
81 	{ 51, 0x0001 },
82 	{ 52, 0x0039 },
83 	{ 53, 0x0039 },
84 	{ 54, 0x0039 },
85 	{ 55, 0x0039 },
86 	{ 56, 0x0001 },
87 	{ 57, 0x0001 },
88 };
89 
90 static bool wm8978_volatile(struct device *dev, unsigned int reg)
91 {
92 	return reg == WM8978_RESET;
93 }
94 
95 /* codec private data */
96 struct wm8978_priv {
97 	struct regmap *regmap;
98 	unsigned int f_pllout;
99 	unsigned int f_mclk;
100 	unsigned int f_256fs;
101 	unsigned int f_opclk;
102 	int mclk_idx;
103 	enum wm8978_sysclk_src sysclk;
104 };
105 
106 static const char *wm8978_companding[] = {"Off", "NC", "u-law", "A-law"};
107 static const char *wm8978_eqmode[] = {"Capture", "Playback"};
108 static const char *wm8978_bw[] = {"Narrow", "Wide"};
109 static const char *wm8978_eq1[] = {"80Hz", "105Hz", "135Hz", "175Hz"};
110 static const char *wm8978_eq2[] = {"230Hz", "300Hz", "385Hz", "500Hz"};
111 static const char *wm8978_eq3[] = {"650Hz", "850Hz", "1.1kHz", "1.4kHz"};
112 static const char *wm8978_eq4[] = {"1.8kHz", "2.4kHz", "3.2kHz", "4.1kHz"};
113 static const char *wm8978_eq5[] = {"5.3kHz", "6.9kHz", "9kHz", "11.7kHz"};
114 static const char *wm8978_alc3[] = {"ALC", "Limiter"};
115 static const char *wm8978_alc1[] = {"Off", "Right", "Left", "Both"};
116 
117 static SOC_ENUM_SINGLE_DECL(adc_compand, WM8978_COMPANDING_CONTROL, 1,
118 			    wm8978_companding);
119 static SOC_ENUM_SINGLE_DECL(dac_compand, WM8978_COMPANDING_CONTROL, 3,
120 			    wm8978_companding);
121 static SOC_ENUM_SINGLE_DECL(eqmode, WM8978_EQ1, 8, wm8978_eqmode);
122 static SOC_ENUM_SINGLE_DECL(eq1, WM8978_EQ1, 5, wm8978_eq1);
123 static SOC_ENUM_SINGLE_DECL(eq2bw, WM8978_EQ2, 8, wm8978_bw);
124 static SOC_ENUM_SINGLE_DECL(eq2, WM8978_EQ2, 5, wm8978_eq2);
125 static SOC_ENUM_SINGLE_DECL(eq3bw, WM8978_EQ3, 8, wm8978_bw);
126 static SOC_ENUM_SINGLE_DECL(eq3, WM8978_EQ3, 5, wm8978_eq3);
127 static SOC_ENUM_SINGLE_DECL(eq4bw, WM8978_EQ4, 8, wm8978_bw);
128 static SOC_ENUM_SINGLE_DECL(eq4, WM8978_EQ4, 5, wm8978_eq4);
129 static SOC_ENUM_SINGLE_DECL(eq5, WM8978_EQ5, 5, wm8978_eq5);
130 static SOC_ENUM_SINGLE_DECL(alc3, WM8978_ALC_CONTROL_3, 8, wm8978_alc3);
131 static SOC_ENUM_SINGLE_DECL(alc1, WM8978_ALC_CONTROL_1, 7, wm8978_alc1);
132 
133 static const DECLARE_TLV_DB_SCALE(digital_tlv, -12750, 50, 1);
134 static const DECLARE_TLV_DB_SCALE(eq_tlv, -1200, 100, 0);
135 static const DECLARE_TLV_DB_SCALE(inpga_tlv, -1200, 75, 0);
136 static const DECLARE_TLV_DB_SCALE(spk_tlv, -5700, 100, 0);
137 static const DECLARE_TLV_DB_SCALE(boost_tlv, -1500, 300, 1);
138 static const DECLARE_TLV_DB_SCALE(limiter_tlv, 0, 100, 0);
139 
140 static const struct snd_kcontrol_new wm8978_snd_controls[] = {
141 
142 	SOC_SINGLE("Digital Loopback Switch",
143 		WM8978_COMPANDING_CONTROL, 0, 1, 0),
144 
145 	SOC_ENUM("ADC Companding", adc_compand),
146 	SOC_ENUM("DAC Companding", dac_compand),
147 
148 	SOC_DOUBLE("DAC Inversion Switch", WM8978_DAC_CONTROL, 0, 1, 1, 0),
149 
150 	SOC_DOUBLE_R_TLV("PCM Volume",
151 		WM8978_LEFT_DAC_DIGITAL_VOLUME, WM8978_RIGHT_DAC_DIGITAL_VOLUME,
152 		0, 255, 0, digital_tlv),
153 
154 	SOC_SINGLE("High Pass Filter Switch", WM8978_ADC_CONTROL, 8, 1, 0),
155 	SOC_SINGLE("High Pass Cut Off", WM8978_ADC_CONTROL, 4, 7, 0),
156 	SOC_DOUBLE("ADC Inversion Switch", WM8978_ADC_CONTROL, 0, 1, 1, 0),
157 
158 	SOC_DOUBLE_R_TLV("ADC Volume",
159 		WM8978_LEFT_ADC_DIGITAL_VOLUME, WM8978_RIGHT_ADC_DIGITAL_VOLUME,
160 		0, 255, 0, digital_tlv),
161 
162 	SOC_ENUM("Equaliser Function", eqmode),
163 	SOC_ENUM("EQ1 Cut Off", eq1),
164 	SOC_SINGLE_TLV("EQ1 Volume", WM8978_EQ1,  0, 24, 1, eq_tlv),
165 
166 	SOC_ENUM("Equaliser EQ2 Bandwidth", eq2bw),
167 	SOC_ENUM("EQ2 Cut Off", eq2),
168 	SOC_SINGLE_TLV("EQ2 Volume", WM8978_EQ2,  0, 24, 1, eq_tlv),
169 
170 	SOC_ENUM("Equaliser EQ3 Bandwidth", eq3bw),
171 	SOC_ENUM("EQ3 Cut Off", eq3),
172 	SOC_SINGLE_TLV("EQ3 Volume", WM8978_EQ3,  0, 24, 1, eq_tlv),
173 
174 	SOC_ENUM("Equaliser EQ4 Bandwidth", eq4bw),
175 	SOC_ENUM("EQ4 Cut Off", eq4),
176 	SOC_SINGLE_TLV("EQ4 Volume", WM8978_EQ4,  0, 24, 1, eq_tlv),
177 
178 	SOC_ENUM("EQ5 Cut Off", eq5),
179 	SOC_SINGLE_TLV("EQ5 Volume", WM8978_EQ5, 0, 24, 1, eq_tlv),
180 
181 	SOC_SINGLE("DAC Playback Limiter Switch",
182 		WM8978_DAC_LIMITER_1, 8, 1, 0),
183 	SOC_SINGLE("DAC Playback Limiter Decay",
184 		WM8978_DAC_LIMITER_1, 4, 15, 0),
185 	SOC_SINGLE("DAC Playback Limiter Attack",
186 		WM8978_DAC_LIMITER_1, 0, 15, 0),
187 
188 	SOC_SINGLE("DAC Playback Limiter Threshold",
189 		WM8978_DAC_LIMITER_2, 4, 7, 0),
190 	SOC_SINGLE_TLV("DAC Playback Limiter Volume",
191 		WM8978_DAC_LIMITER_2, 0, 12, 0, limiter_tlv),
192 
193 	SOC_ENUM("ALC Enable Switch", alc1),
194 	SOC_SINGLE("ALC Capture Min Gain", WM8978_ALC_CONTROL_1, 0, 7, 0),
195 	SOC_SINGLE("ALC Capture Max Gain", WM8978_ALC_CONTROL_1, 3, 7, 0),
196 
197 	SOC_SINGLE("ALC Capture Hold", WM8978_ALC_CONTROL_2, 4, 10, 0),
198 	SOC_SINGLE("ALC Capture Target", WM8978_ALC_CONTROL_2, 0, 15, 0),
199 
200 	SOC_ENUM("ALC Capture Mode", alc3),
201 	SOC_SINGLE("ALC Capture Decay", WM8978_ALC_CONTROL_3, 4, 10, 0),
202 	SOC_SINGLE("ALC Capture Attack", WM8978_ALC_CONTROL_3, 0, 10, 0),
203 
204 	SOC_SINGLE("ALC Capture Noise Gate Switch", WM8978_NOISE_GATE, 3, 1, 0),
205 	SOC_SINGLE("ALC Capture Noise Gate Threshold",
206 		WM8978_NOISE_GATE, 0, 7, 0),
207 
208 	SOC_DOUBLE_R("Capture PGA ZC Switch",
209 		WM8978_LEFT_INP_PGA_CONTROL, WM8978_RIGHT_INP_PGA_CONTROL,
210 		7, 1, 0),
211 
212 	/* OUT1 - Headphones */
213 	SOC_DOUBLE_R("Headphone Playback ZC Switch",
214 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL, 7, 1, 0),
215 
216 	SOC_DOUBLE_R_TLV("Headphone Playback Volume",
217 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL,
218 		0, 63, 0, spk_tlv),
219 
220 	/* OUT2 - Speakers */
221 	SOC_DOUBLE_R("Speaker Playback ZC Switch",
222 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL, 7, 1, 0),
223 
224 	SOC_DOUBLE_R_TLV("Speaker Playback Volume",
225 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL,
226 		0, 63, 0, spk_tlv),
227 
228 	/* OUT3/4 - Line Output */
229 	SOC_DOUBLE_R("Line Playback Switch",
230 		WM8978_OUT3_MIXER_CONTROL, WM8978_OUT4_MIXER_CONTROL, 6, 1, 1),
231 
232 	/* Mixer #3: Boost (Input) mixer */
233 	SOC_DOUBLE_R("PGA Boost (+20dB)",
234 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
235 		8, 1, 0),
236 	SOC_DOUBLE_R_TLV("L2/R2 Boost Volume",
237 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
238 		4, 7, 0, boost_tlv),
239 	SOC_DOUBLE_R_TLV("Aux Boost Volume",
240 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
241 		0, 7, 0, boost_tlv),
242 
243 	/* Input PGA volume */
244 	SOC_DOUBLE_R_TLV("Input PGA Volume",
245 		WM8978_LEFT_INP_PGA_CONTROL, WM8978_RIGHT_INP_PGA_CONTROL,
246 		0, 63, 0, inpga_tlv),
247 
248 	/* Headphone */
249 	SOC_DOUBLE_R("Headphone Switch",
250 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL, 6, 1, 1),
251 
252 	/* Speaker */
253 	SOC_DOUBLE_R("Speaker Switch",
254 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL, 6, 1, 1),
255 
256 	/* DAC / ADC oversampling */
257 	SOC_SINGLE("DAC 128x Oversampling Switch", WM8978_DAC_CONTROL,
258 		   5, 1, 0),
259 	SOC_SINGLE("ADC 128x Oversampling Switch", WM8978_ADC_CONTROL,
260 		   5, 1, 0),
261 };
262 
263 /* Mixer #1: Output (OUT1, OUT2) Mixer: mix AUX, Input mixer output and DAC */
264 static const struct snd_kcontrol_new wm8978_left_out_mixer[] = {
265 	SOC_DAPM_SINGLE("Line Bypass Switch", WM8978_LEFT_MIXER_CONTROL, 1, 1, 0),
266 	SOC_DAPM_SINGLE("Aux Playback Switch", WM8978_LEFT_MIXER_CONTROL, 5, 1, 0),
267 	SOC_DAPM_SINGLE("PCM Playback Switch", WM8978_LEFT_MIXER_CONTROL, 0, 1, 0),
268 };
269 
270 static const struct snd_kcontrol_new wm8978_right_out_mixer[] = {
271 	SOC_DAPM_SINGLE("Line Bypass Switch", WM8978_RIGHT_MIXER_CONTROL, 1, 1, 0),
272 	SOC_DAPM_SINGLE("Aux Playback Switch", WM8978_RIGHT_MIXER_CONTROL, 5, 1, 0),
273 	SOC_DAPM_SINGLE("PCM Playback Switch", WM8978_RIGHT_MIXER_CONTROL, 0, 1, 0),
274 };
275 
276 /* OUT3/OUT4 Mixer not implemented */
277 
278 /* Mixer #2: Input PGA Mute */
279 static const struct snd_kcontrol_new wm8978_left_input_mixer[] = {
280 	SOC_DAPM_SINGLE("L2 Switch", WM8978_INPUT_CONTROL, 2, 1, 0),
281 	SOC_DAPM_SINGLE("MicN Switch", WM8978_INPUT_CONTROL, 1, 1, 0),
282 	SOC_DAPM_SINGLE("MicP Switch", WM8978_INPUT_CONTROL, 0, 1, 0),
283 };
284 static const struct snd_kcontrol_new wm8978_right_input_mixer[] = {
285 	SOC_DAPM_SINGLE("R2 Switch", WM8978_INPUT_CONTROL, 6, 1, 0),
286 	SOC_DAPM_SINGLE("MicN Switch", WM8978_INPUT_CONTROL, 5, 1, 0),
287 	SOC_DAPM_SINGLE("MicP Switch", WM8978_INPUT_CONTROL, 4, 1, 0),
288 };
289 
290 static const struct snd_soc_dapm_widget wm8978_dapm_widgets[] = {
291 	SND_SOC_DAPM_DAC("Left DAC", "Left HiFi Playback",
292 			 WM8978_POWER_MANAGEMENT_3, 0, 0),
293 	SND_SOC_DAPM_DAC("Right DAC", "Right HiFi Playback",
294 			 WM8978_POWER_MANAGEMENT_3, 1, 0),
295 	SND_SOC_DAPM_ADC("Left ADC", "Left HiFi Capture",
296 			 WM8978_POWER_MANAGEMENT_2, 0, 0),
297 	SND_SOC_DAPM_ADC("Right ADC", "Right HiFi Capture",
298 			 WM8978_POWER_MANAGEMENT_2, 1, 0),
299 
300 	/* Mixer #1: OUT1,2 */
301 	SOC_MIXER_ARRAY("Left Output Mixer", WM8978_POWER_MANAGEMENT_3,
302 			2, 0, wm8978_left_out_mixer),
303 	SOC_MIXER_ARRAY("Right Output Mixer", WM8978_POWER_MANAGEMENT_3,
304 			3, 0, wm8978_right_out_mixer),
305 
306 	SOC_MIXER_ARRAY("Left Input Mixer", WM8978_POWER_MANAGEMENT_2,
307 			2, 0, wm8978_left_input_mixer),
308 	SOC_MIXER_ARRAY("Right Input Mixer", WM8978_POWER_MANAGEMENT_2,
309 			3, 0, wm8978_right_input_mixer),
310 
311 	SND_SOC_DAPM_PGA("Left Boost Mixer", WM8978_POWER_MANAGEMENT_2,
312 			 4, 0, NULL, 0),
313 	SND_SOC_DAPM_PGA("Right Boost Mixer", WM8978_POWER_MANAGEMENT_2,
314 			 5, 0, NULL, 0),
315 
316 	SND_SOC_DAPM_PGA("Left Capture PGA", WM8978_LEFT_INP_PGA_CONTROL,
317 			 6, 1, NULL, 0),
318 	SND_SOC_DAPM_PGA("Right Capture PGA", WM8978_RIGHT_INP_PGA_CONTROL,
319 			 6, 1, NULL, 0),
320 
321 	SND_SOC_DAPM_PGA("Left Headphone Out", WM8978_POWER_MANAGEMENT_2,
322 			 7, 0, NULL, 0),
323 	SND_SOC_DAPM_PGA("Right Headphone Out", WM8978_POWER_MANAGEMENT_2,
324 			 8, 0, NULL, 0),
325 
326 	SND_SOC_DAPM_PGA("Left Speaker Out", WM8978_POWER_MANAGEMENT_3,
327 			 6, 0, NULL, 0),
328 	SND_SOC_DAPM_PGA("Right Speaker Out", WM8978_POWER_MANAGEMENT_3,
329 			 5, 0, NULL, 0),
330 
331 	SND_SOC_DAPM_MIXER("OUT4 VMID", WM8978_POWER_MANAGEMENT_3,
332 			   8, 0, NULL, 0),
333 
334 	SND_SOC_DAPM_MICBIAS("Mic Bias", WM8978_POWER_MANAGEMENT_1, 4, 0),
335 
336 	SND_SOC_DAPM_INPUT("LMICN"),
337 	SND_SOC_DAPM_INPUT("LMICP"),
338 	SND_SOC_DAPM_INPUT("RMICN"),
339 	SND_SOC_DAPM_INPUT("RMICP"),
340 	SND_SOC_DAPM_INPUT("LAUX"),
341 	SND_SOC_DAPM_INPUT("RAUX"),
342 	SND_SOC_DAPM_INPUT("L2"),
343 	SND_SOC_DAPM_INPUT("R2"),
344 	SND_SOC_DAPM_OUTPUT("LHP"),
345 	SND_SOC_DAPM_OUTPUT("RHP"),
346 	SND_SOC_DAPM_OUTPUT("LSPK"),
347 	SND_SOC_DAPM_OUTPUT("RSPK"),
348 };
349 
350 static const struct snd_soc_dapm_route wm8978_dapm_routes[] = {
351 	/* Output mixer */
352 	{"Right Output Mixer", "PCM Playback Switch", "Right DAC"},
353 	{"Right Output Mixer", "Aux Playback Switch", "RAUX"},
354 	{"Right Output Mixer", "Line Bypass Switch", "Right Boost Mixer"},
355 
356 	{"Left Output Mixer", "PCM Playback Switch", "Left DAC"},
357 	{"Left Output Mixer", "Aux Playback Switch", "LAUX"},
358 	{"Left Output Mixer", "Line Bypass Switch", "Left Boost Mixer"},
359 
360 	/* Outputs */
361 	{"Right Headphone Out", NULL, "Right Output Mixer"},
362 	{"RHP", NULL, "Right Headphone Out"},
363 
364 	{"Left Headphone Out", NULL, "Left Output Mixer"},
365 	{"LHP", NULL, "Left Headphone Out"},
366 
367 	{"Right Speaker Out", NULL, "Right Output Mixer"},
368 	{"RSPK", NULL, "Right Speaker Out"},
369 
370 	{"Left Speaker Out", NULL, "Left Output Mixer"},
371 	{"LSPK", NULL, "Left Speaker Out"},
372 
373 	/* Boost Mixer */
374 	{"Right ADC", NULL, "Right Boost Mixer"},
375 
376 	{"Right Boost Mixer", NULL, "RAUX"},
377 	{"Right Boost Mixer", NULL, "Right Capture PGA"},
378 	{"Right Boost Mixer", NULL, "R2"},
379 
380 	{"Left ADC", NULL, "Left Boost Mixer"},
381 
382 	{"Left Boost Mixer", NULL, "LAUX"},
383 	{"Left Boost Mixer", NULL, "Left Capture PGA"},
384 	{"Left Boost Mixer", NULL, "L2"},
385 
386 	/* Input PGA */
387 	{"Right Capture PGA", NULL, "Right Input Mixer"},
388 	{"Left Capture PGA", NULL, "Left Input Mixer"},
389 
390 	{"Right Input Mixer", "R2 Switch", "R2"},
391 	{"Right Input Mixer", "MicN Switch", "RMICN"},
392 	{"Right Input Mixer", "MicP Switch", "RMICP"},
393 
394 	{"Left Input Mixer", "L2 Switch", "L2"},
395 	{"Left Input Mixer", "MicN Switch", "LMICN"},
396 	{"Left Input Mixer", "MicP Switch", "LMICP"},
397 };
398 
399 /* PLL divisors */
400 struct wm8978_pll_div {
401 	u32 k;
402 	u8 n;
403 	u8 div2;
404 };
405 
406 #define FIXED_PLL_SIZE (1 << 24)
407 
408 static void pll_factors(struct snd_soc_component *component,
409 		struct wm8978_pll_div *pll_div, unsigned int target, unsigned int source)
410 {
411 	u64 k_part;
412 	unsigned int k, n_div, n_mod;
413 
414 	n_div = target / source;
415 	if (n_div < 6) {
416 		source >>= 1;
417 		pll_div->div2 = 1;
418 		n_div = target / source;
419 	} else {
420 		pll_div->div2 = 0;
421 	}
422 
423 	if (n_div < 6 || n_div > 12)
424 		dev_warn(component->dev,
425 			 "WM8978 N value exceeds recommended range! N = %u\n",
426 			 n_div);
427 
428 	pll_div->n = n_div;
429 	n_mod = target - source * n_div;
430 	k_part = FIXED_PLL_SIZE * (long long)n_mod + source / 2;
431 
432 	do_div(k_part, source);
433 
434 	k = k_part & 0xFFFFFFFF;
435 
436 	pll_div->k = k;
437 }
438 
439 /* MCLK dividers */
440 static const int mclk_numerator[]	= {1, 3, 2, 3, 4, 6, 8, 12};
441 static const int mclk_denominator[]	= {1, 2, 1, 1, 1, 1, 1, 1};
442 
443 /*
444  * find index >= idx, such that, for a given f_out,
445  * 3 * f_mclk / 4 <= f_PLLOUT < 13 * f_mclk / 4
446  * f_out can be f_256fs or f_opclk, currently only used for f_256fs. Can be
447  * generalised for f_opclk with suitable coefficient arrays, but currently
448  * the OPCLK divisor is calculated directly, not iteratively.
449  */
450 static int wm8978_enum_mclk(unsigned int f_out, unsigned int f_mclk,
451 			    unsigned int *f_pllout)
452 {
453 	int i;
454 
455 	for (i = 0; i < ARRAY_SIZE(mclk_numerator); i++) {
456 		unsigned int f_pllout_x4 = 4 * f_out * mclk_numerator[i] /
457 			mclk_denominator[i];
458 		if (3 * f_mclk <= f_pllout_x4 && f_pllout_x4 < 13 * f_mclk) {
459 			*f_pllout = f_pllout_x4 / 4;
460 			return i;
461 		}
462 	}
463 
464 	return -EINVAL;
465 }
466 
467 /*
468  * Calculate internal frequencies and dividers, according to Figure 40
469  * "PLL and Clock Select Circuit" in WM8978 datasheet Rev. 2.6
470  */
471 static int wm8978_configure_pll(struct snd_soc_component *component)
472 {
473 	struct wm8978_priv *wm8978 = snd_soc_component_get_drvdata(component);
474 	struct wm8978_pll_div pll_div;
475 	unsigned int f_opclk = wm8978->f_opclk, f_mclk = wm8978->f_mclk,
476 		f_256fs = wm8978->f_256fs;
477 	unsigned int f2;
478 
479 	if (!f_mclk)
480 		return -EINVAL;
481 
482 	if (f_opclk) {
483 		unsigned int opclk_div;
484 		/* Cannot set up MCLK divider now, do later */
485 		wm8978->mclk_idx = -1;
486 
487 		/*
488 		 * The user needs OPCLK. Choose OPCLKDIV to put
489 		 * 6 <= R = f2 / f1 < 13, 1 <= OPCLKDIV <= 4.
490 		 * f_opclk = f_mclk * prescale * R / 4 / OPCLKDIV, where
491 		 * prescale = 1, or prescale = 2. Prescale is calculated inside
492 		 * pll_factors(). We have to select f_PLLOUT, such that
493 		 * f_mclk * 3 / 4 <= f_PLLOUT < f_mclk * 13 / 4. Must be
494 		 * f_mclk * 3 / 16 <= f_opclk < f_mclk * 13 / 4.
495 		 */
496 		if (16 * f_opclk < 3 * f_mclk || 4 * f_opclk >= 13 * f_mclk)
497 			return -EINVAL;
498 
499 		if (4 * f_opclk < 3 * f_mclk)
500 			/* Have to use OPCLKDIV */
501 			opclk_div = (3 * f_mclk / 4 + f_opclk - 1) / f_opclk;
502 		else
503 			opclk_div = 1;
504 
505 		dev_dbg(component->dev, "%s: OPCLKDIV=%d\n", __func__, opclk_div);
506 
507 		snd_soc_component_update_bits(component, WM8978_GPIO_CONTROL, 0x30,
508 				    (opclk_div - 1) << 4);
509 
510 		wm8978->f_pllout = f_opclk * opclk_div;
511 	} else if (f_256fs) {
512 		/*
513 		 * Not using OPCLK, but PLL is used for the codec, choose R:
514 		 * 6 <= R = f2 / f1 < 13, to put 1 <= MCLKDIV <= 12.
515 		 * f_256fs = f_mclk * prescale * R / 4 / MCLKDIV, where
516 		 * prescale = 1, or prescale = 2. Prescale is calculated inside
517 		 * pll_factors(). We have to select f_PLLOUT, such that
518 		 * f_mclk * 3 / 4 <= f_PLLOUT < f_mclk * 13 / 4. Must be
519 		 * f_mclk * 3 / 48 <= f_256fs < f_mclk * 13 / 4. This means MCLK
520 		 * must be 3.781MHz <= f_MCLK <= 32.768MHz
521 		 */
522 		int idx = wm8978_enum_mclk(f_256fs, f_mclk, &wm8978->f_pllout);
523 		if (idx < 0)
524 			return idx;
525 
526 		wm8978->mclk_idx = idx;
527 	} else {
528 		return -EINVAL;
529 	}
530 
531 	f2 = wm8978->f_pllout * 4;
532 
533 	dev_dbg(component->dev, "%s: f_MCLK=%uHz, f_PLLOUT=%uHz\n", __func__,
534 		wm8978->f_mclk, wm8978->f_pllout);
535 
536 	pll_factors(component, &pll_div, f2, wm8978->f_mclk);
537 
538 	dev_dbg(component->dev, "%s: calculated PLL N=0x%x, K=0x%x, div2=%d\n",
539 		__func__, pll_div.n, pll_div.k, pll_div.div2);
540 
541 	/* Turn PLL off for configuration... */
542 	snd_soc_component_update_bits(component, WM8978_POWER_MANAGEMENT_1, 0x20, 0);
543 
544 	snd_soc_component_write(component, WM8978_PLL_N, (pll_div.div2 << 4) | pll_div.n);
545 	snd_soc_component_write(component, WM8978_PLL_K1, pll_div.k >> 18);
546 	snd_soc_component_write(component, WM8978_PLL_K2, (pll_div.k >> 9) & 0x1ff);
547 	snd_soc_component_write(component, WM8978_PLL_K3, pll_div.k & 0x1ff);
548 
549 	/* ...and on again */
550 	snd_soc_component_update_bits(component, WM8978_POWER_MANAGEMENT_1, 0x20, 0x20);
551 
552 	if (f_opclk)
553 		/* Output PLL (OPCLK) to GPIO1 */
554 		snd_soc_component_update_bits(component, WM8978_GPIO_CONTROL, 7, 4);
555 
556 	return 0;
557 }
558 
559 /*
560  * Configure WM8978 clock dividers.
561  */
562 static int wm8978_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
563 				 int div_id, int div)
564 {
565 	struct snd_soc_component *component = codec_dai->component;
566 	struct wm8978_priv *wm8978 = snd_soc_component_get_drvdata(component);
567 	int ret = 0;
568 
569 	switch (div_id) {
570 	case WM8978_OPCLKRATE:
571 		wm8978->f_opclk = div;
572 
573 		if (wm8978->f_mclk)
574 			/*
575 			 * We know the MCLK frequency, the user has requested
576 			 * OPCLK, configure the PLL based on that and start it
577 			 * and OPCLK immediately. We will configure PLL to match
578 			 * user-requested OPCLK frquency as good as possible.
579 			 * In fact, it is likely, that matching the sampling
580 			 * rate, when it becomes known, is more important, and
581 			 * we will not be reconfiguring PLL then, because we
582 			 * must not interrupt OPCLK. But it should be fine,
583 			 * because typically the user will request OPCLK to run
584 			 * at 256fs or 512fs, and for these cases we will also
585 			 * find an exact MCLK divider configuration - it will
586 			 * be equal to or double the OPCLK divisor.
587 			 */
588 			ret = wm8978_configure_pll(component);
589 		break;
590 	case WM8978_BCLKDIV:
591 		if (div & ~0x1c)
592 			return -EINVAL;
593 		snd_soc_component_update_bits(component, WM8978_CLOCKING, 0x1c, div);
594 		break;
595 	default:
596 		return -EINVAL;
597 	}
598 
599 	dev_dbg(component->dev, "%s: ID %d, value %u\n", __func__, div_id, div);
600 
601 	return ret;
602 }
603 
604 /*
605  * @freq:	when .set_pll() us not used, freq is codec MCLK input frequency
606  */
607 static int wm8978_set_dai_sysclk(struct snd_soc_dai *codec_dai, int clk_id,
608 				 unsigned int freq, int dir)
609 {
610 	struct snd_soc_component *component = codec_dai->component;
611 	struct wm8978_priv *wm8978 = snd_soc_component_get_drvdata(component);
612 	int ret = 0;
613 
614 	dev_dbg(component->dev, "%s: ID %d, freq %u\n", __func__, clk_id, freq);
615 
616 	if (freq) {
617 		wm8978->f_mclk = freq;
618 
619 		/* Even if MCLK is used for system clock, might have to drive OPCLK */
620 		if (wm8978->f_opclk)
621 			ret = wm8978_configure_pll(component);
622 
623 		/* Our sysclk is fixed to 256 * fs, will configure in .hw_params()  */
624 
625 		if (!ret)
626 			wm8978->sysclk = clk_id;
627 	}
628 
629 	if (wm8978->sysclk == WM8978_PLL && (!freq || clk_id == WM8978_MCLK)) {
630 		/* Clock CODEC directly from MCLK */
631 		snd_soc_component_update_bits(component, WM8978_CLOCKING, 0x100, 0);
632 
633 		/* GPIO1 into default mode as input - before configuring PLL */
634 		snd_soc_component_update_bits(component, WM8978_GPIO_CONTROL, 7, 0);
635 
636 		/* Turn off PLL */
637 		snd_soc_component_update_bits(component, WM8978_POWER_MANAGEMENT_1, 0x20, 0);
638 		wm8978->sysclk = WM8978_MCLK;
639 		wm8978->f_pllout = 0;
640 		wm8978->f_opclk = 0;
641 	}
642 
643 	return ret;
644 }
645 
646 /*
647  * Set ADC and Voice DAC format.
648  */
649 static int wm8978_set_dai_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
650 {
651 	struct snd_soc_component *component = codec_dai->component;
652 	/*
653 	 * BCLK polarity mask = 0x100, LRC clock polarity mask = 0x80,
654 	 * Data Format mask = 0x18: all will be calculated anew
655 	 */
656 	u16 iface = snd_soc_component_read(component, WM8978_AUDIO_INTERFACE) & ~0x198;
657 	u16 clk = snd_soc_component_read(component, WM8978_CLOCKING);
658 
659 	dev_dbg(component->dev, "%s\n", __func__);
660 
661 	/* set master/slave audio interface */
662 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
663 	case SND_SOC_DAIFMT_CBM_CFM:
664 		clk |= 1;
665 		break;
666 	case SND_SOC_DAIFMT_CBS_CFS:
667 		clk &= ~1;
668 		break;
669 	default:
670 		return -EINVAL;
671 	}
672 
673 	/* interface format */
674 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
675 	case SND_SOC_DAIFMT_I2S:
676 		iface |= 0x10;
677 		break;
678 	case SND_SOC_DAIFMT_RIGHT_J:
679 		break;
680 	case SND_SOC_DAIFMT_LEFT_J:
681 		iface |= 0x8;
682 		break;
683 	case SND_SOC_DAIFMT_DSP_A:
684 		iface |= 0x18;
685 		break;
686 	default:
687 		return -EINVAL;
688 	}
689 
690 	/* clock inversion */
691 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
692 	case SND_SOC_DAIFMT_NB_NF:
693 		break;
694 	case SND_SOC_DAIFMT_IB_IF:
695 		iface |= 0x180;
696 		break;
697 	case SND_SOC_DAIFMT_IB_NF:
698 		iface |= 0x100;
699 		break;
700 	case SND_SOC_DAIFMT_NB_IF:
701 		iface |= 0x80;
702 		break;
703 	default:
704 		return -EINVAL;
705 	}
706 
707 	snd_soc_component_write(component, WM8978_AUDIO_INTERFACE, iface);
708 	snd_soc_component_write(component, WM8978_CLOCKING, clk);
709 
710 	return 0;
711 }
712 
713 /*
714  * Set PCM DAI bit size and sample rate.
715  */
716 static int wm8978_hw_params(struct snd_pcm_substream *substream,
717 			    struct snd_pcm_hw_params *params,
718 			    struct snd_soc_dai *dai)
719 {
720 	struct snd_soc_component *component = dai->component;
721 	struct wm8978_priv *wm8978 = snd_soc_component_get_drvdata(component);
722 	/* Word length mask = 0x60 */
723 	u16 iface_ctl = snd_soc_component_read(component, WM8978_AUDIO_INTERFACE) & ~0x60;
724 	/* Sampling rate mask = 0xe (for filters) */
725 	u16 add_ctl = snd_soc_component_read(component, WM8978_ADDITIONAL_CONTROL) & ~0xe;
726 	u16 clking = snd_soc_component_read(component, WM8978_CLOCKING);
727 	enum wm8978_sysclk_src current_clk_id = clking & 0x100 ?
728 		WM8978_PLL : WM8978_MCLK;
729 	unsigned int f_sel, diff, diff_best = INT_MAX;
730 	int i, best = 0;
731 
732 	if (!wm8978->f_mclk)
733 		return -EINVAL;
734 
735 	/* bit size */
736 	switch (params_width(params)) {
737 	case 16:
738 		break;
739 	case 20:
740 		iface_ctl |= 0x20;
741 		break;
742 	case 24:
743 		iface_ctl |= 0x40;
744 		break;
745 	case 32:
746 		iface_ctl |= 0x60;
747 		break;
748 	}
749 
750 	/* filter coefficient */
751 	switch (params_rate(params)) {
752 	case 8000:
753 		add_ctl |= 0x5 << 1;
754 		break;
755 	case 11025:
756 		add_ctl |= 0x4 << 1;
757 		break;
758 	case 16000:
759 		add_ctl |= 0x3 << 1;
760 		break;
761 	case 22050:
762 		add_ctl |= 0x2 << 1;
763 		break;
764 	case 32000:
765 		add_ctl |= 0x1 << 1;
766 		break;
767 	case 44100:
768 	case 48000:
769 		break;
770 	}
771 
772 	/* Sampling rate is known now, can configure the MCLK divider */
773 	wm8978->f_256fs = params_rate(params) * 256;
774 
775 	if (wm8978->sysclk == WM8978_MCLK) {
776 		wm8978->mclk_idx = -1;
777 		f_sel = wm8978->f_mclk;
778 	} else {
779 		if (!wm8978->f_opclk) {
780 			/* We only enter here, if OPCLK is not used */
781 			int ret = wm8978_configure_pll(component);
782 			if (ret < 0)
783 				return ret;
784 		}
785 		f_sel = wm8978->f_pllout;
786 	}
787 
788 	if (wm8978->mclk_idx < 0) {
789 		/* Either MCLK is used directly, or OPCLK is used */
790 		if (f_sel < wm8978->f_256fs || f_sel > 12 * wm8978->f_256fs)
791 			return -EINVAL;
792 
793 		for (i = 0; i < ARRAY_SIZE(mclk_numerator); i++) {
794 			diff = abs(wm8978->f_256fs * 3 -
795 				   f_sel * 3 * mclk_denominator[i] / mclk_numerator[i]);
796 
797 			if (diff < diff_best) {
798 				diff_best = diff;
799 				best = i;
800 			}
801 
802 			if (!diff)
803 				break;
804 		}
805 	} else {
806 		/* OPCLK not used, codec driven by PLL */
807 		best = wm8978->mclk_idx;
808 		diff = 0;
809 	}
810 
811 	if (diff)
812 		dev_warn(component->dev, "Imprecise sampling rate: %uHz%s\n",
813 			f_sel * mclk_denominator[best] / mclk_numerator[best] / 256,
814 			wm8978->sysclk == WM8978_MCLK ?
815 			", consider using PLL" : "");
816 
817 	dev_dbg(component->dev, "%s: width %d, rate %u, MCLK divisor #%d\n", __func__,
818 		params_width(params), params_rate(params), best);
819 
820 	/* MCLK divisor mask = 0xe0 */
821 	snd_soc_component_update_bits(component, WM8978_CLOCKING, 0xe0, best << 5);
822 
823 	snd_soc_component_write(component, WM8978_AUDIO_INTERFACE, iface_ctl);
824 	snd_soc_component_write(component, WM8978_ADDITIONAL_CONTROL, add_ctl);
825 
826 	if (wm8978->sysclk != current_clk_id) {
827 		if (wm8978->sysclk == WM8978_PLL)
828 			/* Run CODEC from PLL instead of MCLK */
829 			snd_soc_component_update_bits(component, WM8978_CLOCKING,
830 					    0x100, 0x100);
831 		else
832 			/* Clock CODEC directly from MCLK */
833 			snd_soc_component_update_bits(component, WM8978_CLOCKING, 0x100, 0);
834 	}
835 
836 	return 0;
837 }
838 
839 static int wm8978_mute(struct snd_soc_dai *dai, int mute, int direction)
840 {
841 	struct snd_soc_component *component = dai->component;
842 
843 	dev_dbg(component->dev, "%s: %d\n", __func__, mute);
844 
845 	if (mute)
846 		snd_soc_component_update_bits(component, WM8978_DAC_CONTROL, 0x40, 0x40);
847 	else
848 		snd_soc_component_update_bits(component, WM8978_DAC_CONTROL, 0x40, 0);
849 
850 	return 0;
851 }
852 
853 static int wm8978_set_bias_level(struct snd_soc_component *component,
854 				 enum snd_soc_bias_level level)
855 {
856 	u16 power1 = snd_soc_component_read(component, WM8978_POWER_MANAGEMENT_1) & ~3;
857 
858 	switch (level) {
859 	case SND_SOC_BIAS_ON:
860 	case SND_SOC_BIAS_PREPARE:
861 		power1 |= 1;  /* VMID 75k */
862 		snd_soc_component_write(component, WM8978_POWER_MANAGEMENT_1, power1);
863 		break;
864 	case SND_SOC_BIAS_STANDBY:
865 		/* bit 3: enable bias, bit 2: enable I/O tie off buffer */
866 		power1 |= 0xc;
867 
868 		if (snd_soc_component_get_bias_level(component) == SND_SOC_BIAS_OFF) {
869 			/* Initial cap charge at VMID 5k */
870 			snd_soc_component_write(component, WM8978_POWER_MANAGEMENT_1,
871 				      power1 | 0x3);
872 			mdelay(100);
873 		}
874 
875 		power1 |= 0x2;  /* VMID 500k */
876 		snd_soc_component_write(component, WM8978_POWER_MANAGEMENT_1, power1);
877 		break;
878 	case SND_SOC_BIAS_OFF:
879 		/* Preserve PLL - OPCLK may be used by someone */
880 		snd_soc_component_update_bits(component, WM8978_POWER_MANAGEMENT_1, ~0x20, 0);
881 		snd_soc_component_write(component, WM8978_POWER_MANAGEMENT_2, 0);
882 		snd_soc_component_write(component, WM8978_POWER_MANAGEMENT_3, 0);
883 		break;
884 	}
885 
886 	dev_dbg(component->dev, "%s: %d, %x\n", __func__, level, power1);
887 
888 	return 0;
889 }
890 
891 #define WM8978_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
892 	SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
893 
894 static const struct snd_soc_dai_ops wm8978_dai_ops = {
895 	.hw_params	= wm8978_hw_params,
896 	.mute_stream	= wm8978_mute,
897 	.set_fmt	= wm8978_set_dai_fmt,
898 	.set_clkdiv	= wm8978_set_dai_clkdiv,
899 	.set_sysclk	= wm8978_set_dai_sysclk,
900 	.no_capture_mute = 1,
901 };
902 
903 /* Also supports 12kHz */
904 static struct snd_soc_dai_driver wm8978_dai = {
905 	.name = "wm8978-hifi",
906 	.playback = {
907 		.stream_name = "Playback",
908 		.channels_min = 1,
909 		.channels_max = 2,
910 		.rates = SNDRV_PCM_RATE_8000_48000,
911 		.formats = WM8978_FORMATS,
912 	},
913 	.capture = {
914 		.stream_name = "Capture",
915 		.channels_min = 1,
916 		.channels_max = 2,
917 		.rates = SNDRV_PCM_RATE_8000_48000,
918 		.formats = WM8978_FORMATS,
919 	},
920 	.ops = &wm8978_dai_ops,
921 	.symmetric_rates = 1,
922 };
923 
924 static int wm8978_suspend(struct snd_soc_component *component)
925 {
926 	struct wm8978_priv *wm8978 = snd_soc_component_get_drvdata(component);
927 
928 	snd_soc_component_force_bias_level(component, SND_SOC_BIAS_OFF);
929 	/* Also switch PLL off */
930 	snd_soc_component_write(component, WM8978_POWER_MANAGEMENT_1, 0);
931 
932 	regcache_mark_dirty(wm8978->regmap);
933 
934 	return 0;
935 }
936 
937 static int wm8978_resume(struct snd_soc_component *component)
938 {
939 	struct wm8978_priv *wm8978 = snd_soc_component_get_drvdata(component);
940 
941 	/* Sync reg_cache with the hardware */
942 	regcache_sync(wm8978->regmap);
943 
944 	snd_soc_component_force_bias_level(component, SND_SOC_BIAS_STANDBY);
945 
946 	if (wm8978->f_pllout)
947 		/* Switch PLL on */
948 		snd_soc_component_update_bits(component, WM8978_POWER_MANAGEMENT_1, 0x20, 0x20);
949 
950 	return 0;
951 }
952 
953 /*
954  * These registers contain an "update" bit - bit 8. This means, for example,
955  * that one can write new DAC digital volume for both channels, but only when
956  * the update bit is set, will also the volume be updated - simultaneously for
957  * both channels.
958  */
959 static const int update_reg[] = {
960 	WM8978_LEFT_DAC_DIGITAL_VOLUME,
961 	WM8978_RIGHT_DAC_DIGITAL_VOLUME,
962 	WM8978_LEFT_ADC_DIGITAL_VOLUME,
963 	WM8978_RIGHT_ADC_DIGITAL_VOLUME,
964 	WM8978_LEFT_INP_PGA_CONTROL,
965 	WM8978_RIGHT_INP_PGA_CONTROL,
966 	WM8978_LOUT1_HP_CONTROL,
967 	WM8978_ROUT1_HP_CONTROL,
968 	WM8978_LOUT2_SPK_CONTROL,
969 	WM8978_ROUT2_SPK_CONTROL,
970 };
971 
972 static int wm8978_probe(struct snd_soc_component *component)
973 {
974 	struct wm8978_priv *wm8978 = snd_soc_component_get_drvdata(component);
975 	int i;
976 
977 	/*
978 	 * Set default system clock to PLL, it is more precise, this is also the
979 	 * default hardware setting
980 	 */
981 	wm8978->sysclk = WM8978_PLL;
982 
983 	/*
984 	 * Set the update bit in all registers, that have one. This way all
985 	 * writes to those registers will also cause the update bit to be
986 	 * written.
987 	 */
988 	for (i = 0; i < ARRAY_SIZE(update_reg); i++)
989 		snd_soc_component_update_bits(component, update_reg[i], 0x100, 0x100);
990 
991 	return 0;
992 }
993 
994 static const struct snd_soc_component_driver soc_component_dev_wm8978 = {
995 	.probe			= wm8978_probe,
996 	.suspend		= wm8978_suspend,
997 	.resume			= wm8978_resume,
998 	.set_bias_level		= wm8978_set_bias_level,
999 	.controls		= wm8978_snd_controls,
1000 	.num_controls		= ARRAY_SIZE(wm8978_snd_controls),
1001 	.dapm_widgets		= wm8978_dapm_widgets,
1002 	.num_dapm_widgets	= ARRAY_SIZE(wm8978_dapm_widgets),
1003 	.dapm_routes		= wm8978_dapm_routes,
1004 	.num_dapm_routes	= ARRAY_SIZE(wm8978_dapm_routes),
1005 	.idle_bias_on		= 1,
1006 	.use_pmdown_time	= 1,
1007 	.endianness		= 1,
1008 	.non_legacy_dai_naming	= 1,
1009 };
1010 
1011 static const struct regmap_config wm8978_regmap_config = {
1012 	.reg_bits = 7,
1013 	.val_bits = 9,
1014 
1015 	.max_register = WM8978_MAX_REGISTER,
1016 	.volatile_reg = wm8978_volatile,
1017 
1018 	.cache_type = REGCACHE_RBTREE,
1019 	.reg_defaults = wm8978_reg_defaults,
1020 	.num_reg_defaults = ARRAY_SIZE(wm8978_reg_defaults),
1021 };
1022 
1023 static int wm8978_i2c_probe(struct i2c_client *i2c,
1024 			    const struct i2c_device_id *id)
1025 {
1026 	struct wm8978_priv *wm8978;
1027 	int ret;
1028 
1029 	wm8978 = devm_kzalloc(&i2c->dev, sizeof(struct wm8978_priv),
1030 			      GFP_KERNEL);
1031 	if (wm8978 == NULL)
1032 		return -ENOMEM;
1033 
1034 	wm8978->regmap = devm_regmap_init_i2c(i2c, &wm8978_regmap_config);
1035 	if (IS_ERR(wm8978->regmap)) {
1036 		ret = PTR_ERR(wm8978->regmap);
1037 		dev_err(&i2c->dev, "Failed to allocate regmap: %d\n", ret);
1038 		return ret;
1039 	}
1040 
1041 	i2c_set_clientdata(i2c, wm8978);
1042 
1043 	/* Reset the codec */
1044 	ret = regmap_write(wm8978->regmap, WM8978_RESET, 0);
1045 	if (ret != 0) {
1046 		dev_err(&i2c->dev, "Failed to issue reset: %d\n", ret);
1047 		return ret;
1048 	}
1049 
1050 	ret = devm_snd_soc_register_component(&i2c->dev,
1051 			&soc_component_dev_wm8978, &wm8978_dai, 1);
1052 	if (ret != 0) {
1053 		dev_err(&i2c->dev, "Failed to register CODEC: %d\n", ret);
1054 		return ret;
1055 	}
1056 
1057 	return 0;
1058 }
1059 
1060 static const struct i2c_device_id wm8978_i2c_id[] = {
1061 	{ "wm8978", 0 },
1062 	{ }
1063 };
1064 MODULE_DEVICE_TABLE(i2c, wm8978_i2c_id);
1065 
1066 static const struct of_device_id wm8978_of_match[] = {
1067 	{ .compatible = "wlf,wm8978", },
1068 	{ }
1069 };
1070 MODULE_DEVICE_TABLE(of, wm8978_of_match);
1071 
1072 static struct i2c_driver wm8978_i2c_driver = {
1073 	.driver = {
1074 		.name = "wm8978",
1075 		.of_match_table = wm8978_of_match,
1076 	},
1077 	.probe =    wm8978_i2c_probe,
1078 	.id_table = wm8978_i2c_id,
1079 };
1080 
1081 module_i2c_driver(wm8978_i2c_driver);
1082 
1083 MODULE_DESCRIPTION("ASoC WM8978 codec driver");
1084 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
1085 MODULE_LICENSE("GPL");
1086