xref: /openbmc/linux/sound/soc/codecs/wm8978.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /*
2  * wm8978.c  --  WM8978 ALSA SoC Audio Codec driver
3  *
4  * Copyright (C) 2009-2010 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
5  * Copyright (C) 2007 Carlos Munoz <carlos@kenati.com>
6  * Copyright 2006-2009 Wolfson Microelectronics PLC.
7  * Based on wm8974 and wm8990 by Liam Girdwood <lrg@slimlogic.co.uk>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/delay.h>
19 #include <linux/pm.h>
20 #include <linux/i2c.h>
21 #include <linux/platform_device.h>
22 #include <linux/slab.h>
23 #include <sound/core.h>
24 #include <sound/pcm.h>
25 #include <sound/pcm_params.h>
26 #include <sound/soc.h>
27 #include <sound/initval.h>
28 #include <sound/tlv.h>
29 #include <asm/div64.h>
30 
31 #include "wm8978.h"
32 
33 /* wm8978 register cache. Note that register 0 is not included in the cache. */
34 static const u16 wm8978_reg[WM8978_CACHEREGNUM] = {
35 	0x0000, 0x0000, 0x0000, 0x0000,	/* 0x00...0x03 */
36 	0x0050, 0x0000, 0x0140, 0x0000,	/* 0x04...0x07 */
37 	0x0000, 0x0000, 0x0000, 0x00ff,	/* 0x08...0x0b */
38 	0x00ff, 0x0000, 0x0100, 0x00ff,	/* 0x0c...0x0f */
39 	0x00ff, 0x0000, 0x012c, 0x002c,	/* 0x10...0x13 */
40 	0x002c, 0x002c, 0x002c, 0x0000,	/* 0x14...0x17 */
41 	0x0032, 0x0000, 0x0000, 0x0000,	/* 0x18...0x1b */
42 	0x0000, 0x0000, 0x0000, 0x0000,	/* 0x1c...0x1f */
43 	0x0038, 0x000b, 0x0032, 0x0000,	/* 0x20...0x23 */
44 	0x0008, 0x000c, 0x0093, 0x00e9,	/* 0x24...0x27 */
45 	0x0000, 0x0000, 0x0000, 0x0000,	/* 0x28...0x2b */
46 	0x0033, 0x0010, 0x0010, 0x0100,	/* 0x2c...0x2f */
47 	0x0100, 0x0002, 0x0001, 0x0001,	/* 0x30...0x33 */
48 	0x0039, 0x0039, 0x0039, 0x0039,	/* 0x34...0x37 */
49 	0x0001,	0x0001,			/* 0x38...0x3b */
50 };
51 
52 /* codec private data */
53 struct wm8978_priv {
54 	enum snd_soc_control_type control_type;
55 	void *control_data;
56 	unsigned int f_pllout;
57 	unsigned int f_mclk;
58 	unsigned int f_256fs;
59 	unsigned int f_opclk;
60 	int mclk_idx;
61 	enum wm8978_sysclk_src sysclk;
62 };
63 
64 static const char *wm8978_companding[] = {"Off", "NC", "u-law", "A-law"};
65 static const char *wm8978_eqmode[] = {"Capture", "Playback"};
66 static const char *wm8978_bw[] = {"Narrow", "Wide"};
67 static const char *wm8978_eq1[] = {"80Hz", "105Hz", "135Hz", "175Hz"};
68 static const char *wm8978_eq2[] = {"230Hz", "300Hz", "385Hz", "500Hz"};
69 static const char *wm8978_eq3[] = {"650Hz", "850Hz", "1.1kHz", "1.4kHz"};
70 static const char *wm8978_eq4[] = {"1.8kHz", "2.4kHz", "3.2kHz", "4.1kHz"};
71 static const char *wm8978_eq5[] = {"5.3kHz", "6.9kHz", "9kHz", "11.7kHz"};
72 static const char *wm8978_alc3[] = {"ALC", "Limiter"};
73 static const char *wm8978_alc1[] = {"Off", "Right", "Left", "Both"};
74 
75 static const SOC_ENUM_SINGLE_DECL(adc_compand, WM8978_COMPANDING_CONTROL, 1,
76 				  wm8978_companding);
77 static const SOC_ENUM_SINGLE_DECL(dac_compand, WM8978_COMPANDING_CONTROL, 3,
78 				  wm8978_companding);
79 static const SOC_ENUM_SINGLE_DECL(eqmode, WM8978_EQ1, 8, wm8978_eqmode);
80 static const SOC_ENUM_SINGLE_DECL(eq1, WM8978_EQ1, 5, wm8978_eq1);
81 static const SOC_ENUM_SINGLE_DECL(eq2bw, WM8978_EQ2, 8, wm8978_bw);
82 static const SOC_ENUM_SINGLE_DECL(eq2, WM8978_EQ2, 5, wm8978_eq2);
83 static const SOC_ENUM_SINGLE_DECL(eq3bw, WM8978_EQ3, 8, wm8978_bw);
84 static const SOC_ENUM_SINGLE_DECL(eq3, WM8978_EQ3, 5, wm8978_eq3);
85 static const SOC_ENUM_SINGLE_DECL(eq4bw, WM8978_EQ4, 8, wm8978_bw);
86 static const SOC_ENUM_SINGLE_DECL(eq4, WM8978_EQ4, 5, wm8978_eq4);
87 static const SOC_ENUM_SINGLE_DECL(eq5, WM8978_EQ5, 5, wm8978_eq5);
88 static const SOC_ENUM_SINGLE_DECL(alc3, WM8978_ALC_CONTROL_3, 8, wm8978_alc3);
89 static const SOC_ENUM_SINGLE_DECL(alc1, WM8978_ALC_CONTROL_1, 7, wm8978_alc1);
90 
91 static const DECLARE_TLV_DB_SCALE(digital_tlv, -12750, 50, 1);
92 static const DECLARE_TLV_DB_SCALE(eq_tlv, -1200, 100, 0);
93 static const DECLARE_TLV_DB_SCALE(inpga_tlv, -1200, 75, 0);
94 static const DECLARE_TLV_DB_SCALE(spk_tlv, -5700, 100, 0);
95 static const DECLARE_TLV_DB_SCALE(boost_tlv, -1500, 300, 1);
96 
97 static const struct snd_kcontrol_new wm8978_snd_controls[] = {
98 
99 	SOC_SINGLE("Digital Loopback Switch",
100 		WM8978_COMPANDING_CONTROL, 0, 1, 0),
101 
102 	SOC_ENUM("ADC Companding", adc_compand),
103 	SOC_ENUM("DAC Companding", dac_compand),
104 
105 	SOC_DOUBLE("DAC Inversion Switch", WM8978_DAC_CONTROL, 0, 1, 1, 0),
106 
107 	SOC_DOUBLE_R_TLV("PCM Volume",
108 		WM8978_LEFT_DAC_DIGITAL_VOLUME, WM8978_RIGHT_DAC_DIGITAL_VOLUME,
109 		0, 255, 0, digital_tlv),
110 
111 	SOC_SINGLE("High Pass Filter Switch", WM8978_ADC_CONTROL, 8, 1, 0),
112 	SOC_SINGLE("High Pass Cut Off", WM8978_ADC_CONTROL, 4, 7, 0),
113 	SOC_DOUBLE("ADC Inversion Switch", WM8978_ADC_CONTROL, 0, 1, 1, 0),
114 
115 	SOC_DOUBLE_R_TLV("ADC Volume",
116 		WM8978_LEFT_ADC_DIGITAL_VOLUME, WM8978_RIGHT_ADC_DIGITAL_VOLUME,
117 		0, 255, 0, digital_tlv),
118 
119 	SOC_ENUM("Equaliser Function", eqmode),
120 	SOC_ENUM("EQ1 Cut Off", eq1),
121 	SOC_SINGLE_TLV("EQ1 Volume", WM8978_EQ1,  0, 24, 1, eq_tlv),
122 
123 	SOC_ENUM("Equaliser EQ2 Bandwith", eq2bw),
124 	SOC_ENUM("EQ2 Cut Off", eq2),
125 	SOC_SINGLE_TLV("EQ2 Volume", WM8978_EQ2,  0, 24, 1, eq_tlv),
126 
127 	SOC_ENUM("Equaliser EQ3 Bandwith", eq3bw),
128 	SOC_ENUM("EQ3 Cut Off", eq3),
129 	SOC_SINGLE_TLV("EQ3 Volume", WM8978_EQ3,  0, 24, 1, eq_tlv),
130 
131 	SOC_ENUM("Equaliser EQ4 Bandwith", eq4bw),
132 	SOC_ENUM("EQ4 Cut Off", eq4),
133 	SOC_SINGLE_TLV("EQ4 Volume", WM8978_EQ4,  0, 24, 1, eq_tlv),
134 
135 	SOC_ENUM("EQ5 Cut Off", eq5),
136 	SOC_SINGLE_TLV("EQ5 Volume", WM8978_EQ5, 0, 24, 1, eq_tlv),
137 
138 	SOC_SINGLE("DAC Playback Limiter Switch",
139 		WM8978_DAC_LIMITER_1, 8, 1, 0),
140 	SOC_SINGLE("DAC Playback Limiter Decay",
141 		WM8978_DAC_LIMITER_1, 4, 15, 0),
142 	SOC_SINGLE("DAC Playback Limiter Attack",
143 		WM8978_DAC_LIMITER_1, 0, 15, 0),
144 
145 	SOC_SINGLE("DAC Playback Limiter Threshold",
146 		WM8978_DAC_LIMITER_2, 4, 7, 0),
147 	SOC_SINGLE("DAC Playback Limiter Boost",
148 		WM8978_DAC_LIMITER_2, 0, 15, 0),
149 
150 	SOC_ENUM("ALC Enable Switch", alc1),
151 	SOC_SINGLE("ALC Capture Min Gain", WM8978_ALC_CONTROL_1, 0, 7, 0),
152 	SOC_SINGLE("ALC Capture Max Gain", WM8978_ALC_CONTROL_1, 3, 7, 0),
153 
154 	SOC_SINGLE("ALC Capture Hold", WM8978_ALC_CONTROL_2, 4, 7, 0),
155 	SOC_SINGLE("ALC Capture Target", WM8978_ALC_CONTROL_2, 0, 15, 0),
156 
157 	SOC_ENUM("ALC Capture Mode", alc3),
158 	SOC_SINGLE("ALC Capture Decay", WM8978_ALC_CONTROL_3, 4, 15, 0),
159 	SOC_SINGLE("ALC Capture Attack", WM8978_ALC_CONTROL_3, 0, 15, 0),
160 
161 	SOC_SINGLE("ALC Capture Noise Gate Switch", WM8978_NOISE_GATE, 3, 1, 0),
162 	SOC_SINGLE("ALC Capture Noise Gate Threshold",
163 		WM8978_NOISE_GATE, 0, 7, 0),
164 
165 	SOC_DOUBLE_R("Capture PGA ZC Switch",
166 		WM8978_LEFT_INP_PGA_CONTROL, WM8978_RIGHT_INP_PGA_CONTROL,
167 		7, 1, 0),
168 
169 	/* OUT1 - Headphones */
170 	SOC_DOUBLE_R("Headphone Playback ZC Switch",
171 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL, 7, 1, 0),
172 
173 	SOC_DOUBLE_R_TLV("Headphone Playback Volume",
174 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL,
175 		0, 63, 0, spk_tlv),
176 
177 	/* OUT2 - Speakers */
178 	SOC_DOUBLE_R("Speaker Playback ZC Switch",
179 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL, 7, 1, 0),
180 
181 	SOC_DOUBLE_R_TLV("Speaker Playback Volume",
182 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL,
183 		0, 63, 0, spk_tlv),
184 
185 	/* OUT3/4 - Line Output */
186 	SOC_DOUBLE_R("Line Playback Switch",
187 		WM8978_OUT3_MIXER_CONTROL, WM8978_OUT4_MIXER_CONTROL, 6, 1, 1),
188 
189 	/* Mixer #3: Boost (Input) mixer */
190 	SOC_DOUBLE_R("PGA Boost (+20dB)",
191 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
192 		8, 1, 0),
193 	SOC_DOUBLE_R_TLV("L2/R2 Boost Volume",
194 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
195 		4, 7, 0, boost_tlv),
196 	SOC_DOUBLE_R_TLV("Aux Boost Volume",
197 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
198 		0, 7, 0, boost_tlv),
199 
200 	/* Input PGA volume */
201 	SOC_DOUBLE_R_TLV("Input PGA Volume",
202 		WM8978_LEFT_INP_PGA_CONTROL, WM8978_RIGHT_INP_PGA_CONTROL,
203 		0, 63, 0, inpga_tlv),
204 
205 	/* Headphone */
206 	SOC_DOUBLE_R("Headphone Switch",
207 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL, 6, 1, 1),
208 
209 	/* Speaker */
210 	SOC_DOUBLE_R("Speaker Switch",
211 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL, 6, 1, 1),
212 
213 	/* DAC / ADC oversampling */
214 	SOC_SINGLE("DAC 128x Oversampling Switch", WM8978_DAC_CONTROL, 8, 1, 0),
215 	SOC_SINGLE("ADC 128x Oversampling Switch", WM8978_ADC_CONTROL, 8, 1, 0),
216 };
217 
218 /* Mixer #1: Output (OUT1, OUT2) Mixer: mix AUX, Input mixer output and DAC */
219 static const struct snd_kcontrol_new wm8978_left_out_mixer[] = {
220 	SOC_DAPM_SINGLE("Line Bypass Switch", WM8978_LEFT_MIXER_CONTROL, 1, 1, 0),
221 	SOC_DAPM_SINGLE("Aux Playback Switch", WM8978_LEFT_MIXER_CONTROL, 5, 1, 0),
222 	SOC_DAPM_SINGLE("PCM Playback Switch", WM8978_LEFT_MIXER_CONTROL, 0, 1, 0),
223 };
224 
225 static const struct snd_kcontrol_new wm8978_right_out_mixer[] = {
226 	SOC_DAPM_SINGLE("Line Bypass Switch", WM8978_RIGHT_MIXER_CONTROL, 1, 1, 0),
227 	SOC_DAPM_SINGLE("Aux Playback Switch", WM8978_RIGHT_MIXER_CONTROL, 5, 1, 0),
228 	SOC_DAPM_SINGLE("PCM Playback Switch", WM8978_RIGHT_MIXER_CONTROL, 0, 1, 0),
229 };
230 
231 /* OUT3/OUT4 Mixer not implemented */
232 
233 /* Mixer #2: Input PGA Mute */
234 static const struct snd_kcontrol_new wm8978_left_input_mixer[] = {
235 	SOC_DAPM_SINGLE("L2 Switch", WM8978_INPUT_CONTROL, 2, 1, 0),
236 	SOC_DAPM_SINGLE("MicN Switch", WM8978_INPUT_CONTROL, 1, 1, 0),
237 	SOC_DAPM_SINGLE("MicP Switch", WM8978_INPUT_CONTROL, 0, 1, 0),
238 };
239 static const struct snd_kcontrol_new wm8978_right_input_mixer[] = {
240 	SOC_DAPM_SINGLE("R2 Switch", WM8978_INPUT_CONTROL, 6, 1, 0),
241 	SOC_DAPM_SINGLE("MicN Switch", WM8978_INPUT_CONTROL, 5, 1, 0),
242 	SOC_DAPM_SINGLE("MicP Switch", WM8978_INPUT_CONTROL, 4, 1, 0),
243 };
244 
245 static const struct snd_soc_dapm_widget wm8978_dapm_widgets[] = {
246 	SND_SOC_DAPM_DAC("Left DAC", "Left HiFi Playback",
247 			 WM8978_POWER_MANAGEMENT_3, 0, 0),
248 	SND_SOC_DAPM_DAC("Right DAC", "Right HiFi Playback",
249 			 WM8978_POWER_MANAGEMENT_3, 1, 0),
250 	SND_SOC_DAPM_ADC("Left ADC", "Left HiFi Capture",
251 			 WM8978_POWER_MANAGEMENT_2, 0, 0),
252 	SND_SOC_DAPM_ADC("Right ADC", "Right HiFi Capture",
253 			 WM8978_POWER_MANAGEMENT_2, 1, 0),
254 
255 	/* Mixer #1: OUT1,2 */
256 	SOC_MIXER_ARRAY("Left Output Mixer", WM8978_POWER_MANAGEMENT_3,
257 			2, 0, wm8978_left_out_mixer),
258 	SOC_MIXER_ARRAY("Right Output Mixer", WM8978_POWER_MANAGEMENT_3,
259 			3, 0, wm8978_right_out_mixer),
260 
261 	SOC_MIXER_ARRAY("Left Input Mixer", WM8978_POWER_MANAGEMENT_2,
262 			2, 0, wm8978_left_input_mixer),
263 	SOC_MIXER_ARRAY("Right Input Mixer", WM8978_POWER_MANAGEMENT_2,
264 			3, 0, wm8978_right_input_mixer),
265 
266 	SND_SOC_DAPM_PGA("Left Boost Mixer", WM8978_POWER_MANAGEMENT_2,
267 			 4, 0, NULL, 0),
268 	SND_SOC_DAPM_PGA("Right Boost Mixer", WM8978_POWER_MANAGEMENT_2,
269 			 5, 0, NULL, 0),
270 
271 	SND_SOC_DAPM_PGA("Left Capture PGA", WM8978_LEFT_INP_PGA_CONTROL,
272 			 6, 1, NULL, 0),
273 	SND_SOC_DAPM_PGA("Right Capture PGA", WM8978_RIGHT_INP_PGA_CONTROL,
274 			 6, 1, NULL, 0),
275 
276 	SND_SOC_DAPM_PGA("Left Headphone Out", WM8978_POWER_MANAGEMENT_2,
277 			 7, 0, NULL, 0),
278 	SND_SOC_DAPM_PGA("Right Headphone Out", WM8978_POWER_MANAGEMENT_2,
279 			 8, 0, NULL, 0),
280 
281 	SND_SOC_DAPM_PGA("Left Speaker Out", WM8978_POWER_MANAGEMENT_3,
282 			 6, 0, NULL, 0),
283 	SND_SOC_DAPM_PGA("Right Speaker Out", WM8978_POWER_MANAGEMENT_3,
284 			 5, 0, NULL, 0),
285 
286 	SND_SOC_DAPM_MIXER("OUT4 VMID", WM8978_POWER_MANAGEMENT_3,
287 			   8, 0, NULL, 0),
288 
289 	SND_SOC_DAPM_MICBIAS("Mic Bias", WM8978_POWER_MANAGEMENT_1, 4, 0),
290 
291 	SND_SOC_DAPM_INPUT("LMICN"),
292 	SND_SOC_DAPM_INPUT("LMICP"),
293 	SND_SOC_DAPM_INPUT("RMICN"),
294 	SND_SOC_DAPM_INPUT("RMICP"),
295 	SND_SOC_DAPM_INPUT("LAUX"),
296 	SND_SOC_DAPM_INPUT("RAUX"),
297 	SND_SOC_DAPM_INPUT("L2"),
298 	SND_SOC_DAPM_INPUT("R2"),
299 	SND_SOC_DAPM_OUTPUT("LHP"),
300 	SND_SOC_DAPM_OUTPUT("RHP"),
301 	SND_SOC_DAPM_OUTPUT("LSPK"),
302 	SND_SOC_DAPM_OUTPUT("RSPK"),
303 };
304 
305 static const struct snd_soc_dapm_route audio_map[] = {
306 	/* Output mixer */
307 	{"Right Output Mixer", "PCM Playback Switch", "Right DAC"},
308 	{"Right Output Mixer", "Aux Playback Switch", "RAUX"},
309 	{"Right Output Mixer", "Line Bypass Switch", "Right Boost Mixer"},
310 
311 	{"Left Output Mixer", "PCM Playback Switch", "Left DAC"},
312 	{"Left Output Mixer", "Aux Playback Switch", "LAUX"},
313 	{"Left Output Mixer", "Line Bypass Switch", "Left Boost Mixer"},
314 
315 	/* Outputs */
316 	{"Right Headphone Out", NULL, "Right Output Mixer"},
317 	{"RHP", NULL, "Right Headphone Out"},
318 
319 	{"Left Headphone Out", NULL, "Left Output Mixer"},
320 	{"LHP", NULL, "Left Headphone Out"},
321 
322 	{"Right Speaker Out", NULL, "Right Output Mixer"},
323 	{"RSPK", NULL, "Right Speaker Out"},
324 
325 	{"Left Speaker Out", NULL, "Left Output Mixer"},
326 	{"LSPK", NULL, "Left Speaker Out"},
327 
328 	/* Boost Mixer */
329 	{"Right ADC", NULL, "Right Boost Mixer"},
330 
331 	{"Right Boost Mixer", NULL, "RAUX"},
332 	{"Right Boost Mixer", NULL, "Right Capture PGA"},
333 	{"Right Boost Mixer", NULL, "R2"},
334 
335 	{"Left ADC", NULL, "Left Boost Mixer"},
336 
337 	{"Left Boost Mixer", NULL, "LAUX"},
338 	{"Left Boost Mixer", NULL, "Left Capture PGA"},
339 	{"Left Boost Mixer", NULL, "L2"},
340 
341 	/* Input PGA */
342 	{"Right Capture PGA", NULL, "Right Input Mixer"},
343 	{"Left Capture PGA", NULL, "Left Input Mixer"},
344 
345 	{"Right Input Mixer", "R2 Switch", "R2"},
346 	{"Right Input Mixer", "MicN Switch", "RMICN"},
347 	{"Right Input Mixer", "MicP Switch", "RMICP"},
348 
349 	{"Left Input Mixer", "L2 Switch", "L2"},
350 	{"Left Input Mixer", "MicN Switch", "LMICN"},
351 	{"Left Input Mixer", "MicP Switch", "LMICP"},
352 };
353 
354 static int wm8978_add_widgets(struct snd_soc_codec *codec)
355 {
356 	struct snd_soc_dapm_context *dapm = &codec->dapm;
357 
358 	snd_soc_dapm_new_controls(dapm, wm8978_dapm_widgets,
359 				  ARRAY_SIZE(wm8978_dapm_widgets));
360 	/* set up the WM8978 audio map */
361 	snd_soc_dapm_add_routes(dapm, audio_map, ARRAY_SIZE(audio_map));
362 
363 	return 0;
364 }
365 
366 /* PLL divisors */
367 struct wm8978_pll_div {
368 	u32 k;
369 	u8 n;
370 	u8 div2;
371 };
372 
373 #define FIXED_PLL_SIZE (1 << 24)
374 
375 static void pll_factors(struct snd_soc_codec *codec,
376 		struct wm8978_pll_div *pll_div, unsigned int target, unsigned int source)
377 {
378 	u64 k_part;
379 	unsigned int k, n_div, n_mod;
380 
381 	n_div = target / source;
382 	if (n_div < 6) {
383 		source >>= 1;
384 		pll_div->div2 = 1;
385 		n_div = target / source;
386 	} else {
387 		pll_div->div2 = 0;
388 	}
389 
390 	if (n_div < 6 || n_div > 12)
391 		dev_warn(codec->dev,
392 			 "WM8978 N value exceeds recommended range! N = %u\n",
393 			 n_div);
394 
395 	pll_div->n = n_div;
396 	n_mod = target - source * n_div;
397 	k_part = FIXED_PLL_SIZE * (long long)n_mod + source / 2;
398 
399 	do_div(k_part, source);
400 
401 	k = k_part & 0xFFFFFFFF;
402 
403 	pll_div->k = k;
404 }
405 
406 /* MCLK dividers */
407 static const int mclk_numerator[]	= {1, 3, 2, 3, 4, 6, 8, 12};
408 static const int mclk_denominator[]	= {1, 2, 1, 1, 1, 1, 1, 1};
409 
410 /*
411  * find index >= idx, such that, for a given f_out,
412  * 3 * f_mclk / 4 <= f_PLLOUT < 13 * f_mclk / 4
413  * f_out can be f_256fs or f_opclk, currently only used for f_256fs. Can be
414  * generalised for f_opclk with suitable coefficient arrays, but currently
415  * the OPCLK divisor is calculated directly, not iteratively.
416  */
417 static int wm8978_enum_mclk(unsigned int f_out, unsigned int f_mclk,
418 			    unsigned int *f_pllout)
419 {
420 	int i;
421 
422 	for (i = 0; i < ARRAY_SIZE(mclk_numerator); i++) {
423 		unsigned int f_pllout_x4 = 4 * f_out * mclk_numerator[i] /
424 			mclk_denominator[i];
425 		if (3 * f_mclk <= f_pllout_x4 && f_pllout_x4 < 13 * f_mclk) {
426 			*f_pllout = f_pllout_x4 / 4;
427 			return i;
428 		}
429 	}
430 
431 	return -EINVAL;
432 }
433 
434 /*
435  * Calculate internal frequencies and dividers, according to Figure 40
436  * "PLL and Clock Select Circuit" in WM8978 datasheet Rev. 2.6
437  */
438 static int wm8978_configure_pll(struct snd_soc_codec *codec)
439 {
440 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
441 	struct wm8978_pll_div pll_div;
442 	unsigned int f_opclk = wm8978->f_opclk, f_mclk = wm8978->f_mclk,
443 		f_256fs = wm8978->f_256fs;
444 	unsigned int f2;
445 
446 	if (!f_mclk)
447 		return -EINVAL;
448 
449 	if (f_opclk) {
450 		unsigned int opclk_div;
451 		/* Cannot set up MCLK divider now, do later */
452 		wm8978->mclk_idx = -1;
453 
454 		/*
455 		 * The user needs OPCLK. Choose OPCLKDIV to put
456 		 * 6 <= R = f2 / f1 < 13, 1 <= OPCLKDIV <= 4.
457 		 * f_opclk = f_mclk * prescale * R / 4 / OPCLKDIV, where
458 		 * prescale = 1, or prescale = 2. Prescale is calculated inside
459 		 * pll_factors(). We have to select f_PLLOUT, such that
460 		 * f_mclk * 3 / 4 <= f_PLLOUT < f_mclk * 13 / 4. Must be
461 		 * f_mclk * 3 / 16 <= f_opclk < f_mclk * 13 / 4.
462 		 */
463 		if (16 * f_opclk < 3 * f_mclk || 4 * f_opclk >= 13 * f_mclk)
464 			return -EINVAL;
465 
466 		if (4 * f_opclk < 3 * f_mclk)
467 			/* Have to use OPCLKDIV */
468 			opclk_div = (3 * f_mclk / 4 + f_opclk - 1) / f_opclk;
469 		else
470 			opclk_div = 1;
471 
472 		dev_dbg(codec->dev, "%s: OPCLKDIV=%d\n", __func__, opclk_div);
473 
474 		snd_soc_update_bits(codec, WM8978_GPIO_CONTROL, 0x30,
475 				    (opclk_div - 1) << 4);
476 
477 		wm8978->f_pllout = f_opclk * opclk_div;
478 	} else if (f_256fs) {
479 		/*
480 		 * Not using OPCLK, but PLL is used for the codec, choose R:
481 		 * 6 <= R = f2 / f1 < 13, to put 1 <= MCLKDIV <= 12.
482 		 * f_256fs = f_mclk * prescale * R / 4 / MCLKDIV, where
483 		 * prescale = 1, or prescale = 2. Prescale is calculated inside
484 		 * pll_factors(). We have to select f_PLLOUT, such that
485 		 * f_mclk * 3 / 4 <= f_PLLOUT < f_mclk * 13 / 4. Must be
486 		 * f_mclk * 3 / 48 <= f_256fs < f_mclk * 13 / 4. This means MCLK
487 		 * must be 3.781MHz <= f_MCLK <= 32.768MHz
488 		 */
489 		int idx = wm8978_enum_mclk(f_256fs, f_mclk, &wm8978->f_pllout);
490 		if (idx < 0)
491 			return idx;
492 
493 		wm8978->mclk_idx = idx;
494 
495 		/* GPIO1 into default mode as input - before configuring PLL */
496 		snd_soc_update_bits(codec, WM8978_GPIO_CONTROL, 7, 0);
497 	} else {
498 		return -EINVAL;
499 	}
500 
501 	f2 = wm8978->f_pllout * 4;
502 
503 	dev_dbg(codec->dev, "%s: f_MCLK=%uHz, f_PLLOUT=%uHz\n", __func__,
504 		wm8978->f_mclk, wm8978->f_pllout);
505 
506 	pll_factors(codec, &pll_div, f2, wm8978->f_mclk);
507 
508 	dev_dbg(codec->dev, "%s: calculated PLL N=0x%x, K=0x%x, div2=%d\n",
509 		__func__, pll_div.n, pll_div.k, pll_div.div2);
510 
511 	/* Turn PLL off for configuration... */
512 	snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, 0x20, 0);
513 
514 	snd_soc_write(codec, WM8978_PLL_N, (pll_div.div2 << 4) | pll_div.n);
515 	snd_soc_write(codec, WM8978_PLL_K1, pll_div.k >> 18);
516 	snd_soc_write(codec, WM8978_PLL_K2, (pll_div.k >> 9) & 0x1ff);
517 	snd_soc_write(codec, WM8978_PLL_K3, pll_div.k & 0x1ff);
518 
519 	/* ...and on again */
520 	snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, 0x20, 0x20);
521 
522 	if (f_opclk)
523 		/* Output PLL (OPCLK) to GPIO1 */
524 		snd_soc_update_bits(codec, WM8978_GPIO_CONTROL, 7, 4);
525 
526 	return 0;
527 }
528 
529 /*
530  * Configure WM8978 clock dividers.
531  */
532 static int wm8978_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
533 				 int div_id, int div)
534 {
535 	struct snd_soc_codec *codec = codec_dai->codec;
536 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
537 	int ret = 0;
538 
539 	switch (div_id) {
540 	case WM8978_OPCLKRATE:
541 		wm8978->f_opclk = div;
542 
543 		if (wm8978->f_mclk)
544 			/*
545 			 * We know the MCLK frequency, the user has requested
546 			 * OPCLK, configure the PLL based on that and start it
547 			 * and OPCLK immediately. We will configure PLL to match
548 			 * user-requested OPCLK frquency as good as possible.
549 			 * In fact, it is likely, that matching the sampling
550 			 * rate, when it becomes known, is more important, and
551 			 * we will not be reconfiguring PLL then, because we
552 			 * must not interrupt OPCLK. But it should be fine,
553 			 * because typically the user will request OPCLK to run
554 			 * at 256fs or 512fs, and for these cases we will also
555 			 * find an exact MCLK divider configuration - it will
556 			 * be equal to or double the OPCLK divisor.
557 			 */
558 			ret = wm8978_configure_pll(codec);
559 		break;
560 	case WM8978_BCLKDIV:
561 		if (div & ~0x1c)
562 			return -EINVAL;
563 		snd_soc_update_bits(codec, WM8978_CLOCKING, 0x1c, div);
564 		break;
565 	default:
566 		return -EINVAL;
567 	}
568 
569 	dev_dbg(codec->dev, "%s: ID %d, value %u\n", __func__, div_id, div);
570 
571 	return ret;
572 }
573 
574 /*
575  * @freq:	when .set_pll() us not used, freq is codec MCLK input frequency
576  */
577 static int wm8978_set_dai_sysclk(struct snd_soc_dai *codec_dai, int clk_id,
578 				 unsigned int freq, int dir)
579 {
580 	struct snd_soc_codec *codec = codec_dai->codec;
581 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
582 	int ret = 0;
583 
584 	dev_dbg(codec->dev, "%s: ID %d, freq %u\n", __func__, clk_id, freq);
585 
586 	if (freq) {
587 		wm8978->f_mclk = freq;
588 
589 		/* Even if MCLK is used for system clock, might have to drive OPCLK */
590 		if (wm8978->f_opclk)
591 			ret = wm8978_configure_pll(codec);
592 
593 		/* Our sysclk is fixed to 256 * fs, will configure in .hw_params()  */
594 
595 		if (!ret)
596 			wm8978->sysclk = clk_id;
597 	}
598 
599 	if (wm8978->sysclk == WM8978_PLL && (!freq || clk_id == WM8978_MCLK)) {
600 		/* Clock CODEC directly from MCLK */
601 		snd_soc_update_bits(codec, WM8978_CLOCKING, 0x100, 0);
602 
603 		/* GPIO1 into default mode as input - before configuring PLL */
604 		snd_soc_update_bits(codec, WM8978_GPIO_CONTROL, 7, 0);
605 
606 		/* Turn off PLL */
607 		snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, 0x20, 0);
608 		wm8978->sysclk = WM8978_MCLK;
609 		wm8978->f_pllout = 0;
610 		wm8978->f_opclk = 0;
611 	}
612 
613 	return ret;
614 }
615 
616 /*
617  * Set ADC and Voice DAC format.
618  */
619 static int wm8978_set_dai_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
620 {
621 	struct snd_soc_codec *codec = codec_dai->codec;
622 	/*
623 	 * BCLK polarity mask = 0x100, LRC clock polarity mask = 0x80,
624 	 * Data Format mask = 0x18: all will be calculated anew
625 	 */
626 	u16 iface = snd_soc_read(codec, WM8978_AUDIO_INTERFACE) & ~0x198;
627 	u16 clk = snd_soc_read(codec, WM8978_CLOCKING);
628 
629 	dev_dbg(codec->dev, "%s\n", __func__);
630 
631 	/* set master/slave audio interface */
632 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
633 	case SND_SOC_DAIFMT_CBM_CFM:
634 		clk |= 1;
635 		break;
636 	case SND_SOC_DAIFMT_CBS_CFS:
637 		clk &= ~1;
638 		break;
639 	default:
640 		return -EINVAL;
641 	}
642 
643 	/* interface format */
644 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
645 	case SND_SOC_DAIFMT_I2S:
646 		iface |= 0x10;
647 		break;
648 	case SND_SOC_DAIFMT_RIGHT_J:
649 		break;
650 	case SND_SOC_DAIFMT_LEFT_J:
651 		iface |= 0x8;
652 		break;
653 	case SND_SOC_DAIFMT_DSP_A:
654 		iface |= 0x18;
655 		break;
656 	default:
657 		return -EINVAL;
658 	}
659 
660 	/* clock inversion */
661 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
662 	case SND_SOC_DAIFMT_NB_NF:
663 		break;
664 	case SND_SOC_DAIFMT_IB_IF:
665 		iface |= 0x180;
666 		break;
667 	case SND_SOC_DAIFMT_IB_NF:
668 		iface |= 0x100;
669 		break;
670 	case SND_SOC_DAIFMT_NB_IF:
671 		iface |= 0x80;
672 		break;
673 	default:
674 		return -EINVAL;
675 	}
676 
677 	snd_soc_write(codec, WM8978_AUDIO_INTERFACE, iface);
678 	snd_soc_write(codec, WM8978_CLOCKING, clk);
679 
680 	return 0;
681 }
682 
683 /*
684  * Set PCM DAI bit size and sample rate.
685  */
686 static int wm8978_hw_params(struct snd_pcm_substream *substream,
687 			    struct snd_pcm_hw_params *params,
688 			    struct snd_soc_dai *dai)
689 {
690 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
691 	struct snd_soc_codec *codec = rtd->codec;
692 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
693 	/* Word length mask = 0x60 */
694 	u16 iface_ctl = snd_soc_read(codec, WM8978_AUDIO_INTERFACE) & ~0x60;
695 	/* Sampling rate mask = 0xe (for filters) */
696 	u16 add_ctl = snd_soc_read(codec, WM8978_ADDITIONAL_CONTROL) & ~0xe;
697 	u16 clking = snd_soc_read(codec, WM8978_CLOCKING);
698 	enum wm8978_sysclk_src current_clk_id = clking & 0x100 ?
699 		WM8978_PLL : WM8978_MCLK;
700 	unsigned int f_sel, diff, diff_best = INT_MAX;
701 	int i, best = 0;
702 
703 	if (!wm8978->f_mclk)
704 		return -EINVAL;
705 
706 	/* bit size */
707 	switch (params_format(params)) {
708 	case SNDRV_PCM_FORMAT_S16_LE:
709 		break;
710 	case SNDRV_PCM_FORMAT_S20_3LE:
711 		iface_ctl |= 0x20;
712 		break;
713 	case SNDRV_PCM_FORMAT_S24_LE:
714 		iface_ctl |= 0x40;
715 		break;
716 	case SNDRV_PCM_FORMAT_S32_LE:
717 		iface_ctl |= 0x60;
718 		break;
719 	}
720 
721 	/* filter coefficient */
722 	switch (params_rate(params)) {
723 	case 8000:
724 		add_ctl |= 0x5 << 1;
725 		break;
726 	case 11025:
727 		add_ctl |= 0x4 << 1;
728 		break;
729 	case 16000:
730 		add_ctl |= 0x3 << 1;
731 		break;
732 	case 22050:
733 		add_ctl |= 0x2 << 1;
734 		break;
735 	case 32000:
736 		add_ctl |= 0x1 << 1;
737 		break;
738 	case 44100:
739 	case 48000:
740 		break;
741 	}
742 
743 	/* Sampling rate is known now, can configure the MCLK divider */
744 	wm8978->f_256fs = params_rate(params) * 256;
745 
746 	if (wm8978->sysclk == WM8978_MCLK) {
747 		wm8978->mclk_idx = -1;
748 		f_sel = wm8978->f_mclk;
749 	} else {
750 		if (!wm8978->f_pllout) {
751 			/* We only enter here, if OPCLK is not used */
752 			int ret = wm8978_configure_pll(codec);
753 			if (ret < 0)
754 				return ret;
755 		}
756 		f_sel = wm8978->f_pllout;
757 	}
758 
759 	if (wm8978->mclk_idx < 0) {
760 		/* Either MCLK is used directly, or OPCLK is used */
761 		if (f_sel < wm8978->f_256fs || f_sel > 12 * wm8978->f_256fs)
762 			return -EINVAL;
763 
764 		for (i = 0; i < ARRAY_SIZE(mclk_numerator); i++) {
765 			diff = abs(wm8978->f_256fs * 3 -
766 				   f_sel * 3 * mclk_denominator[i] / mclk_numerator[i]);
767 
768 			if (diff < diff_best) {
769 				diff_best = diff;
770 				best = i;
771 			}
772 
773 			if (!diff)
774 				break;
775 		}
776 	} else {
777 		/* OPCLK not used, codec driven by PLL */
778 		best = wm8978->mclk_idx;
779 		diff = 0;
780 	}
781 
782 	if (diff)
783 		dev_warn(codec->dev, "Imprecise sampling rate: %uHz%s\n",
784 			f_sel * mclk_denominator[best] / mclk_numerator[best] / 256,
785 			wm8978->sysclk == WM8978_MCLK ?
786 			", consider using PLL" : "");
787 
788 	dev_dbg(codec->dev, "%s: fmt %d, rate %u, MCLK divisor #%d\n", __func__,
789 		params_format(params), params_rate(params), best);
790 
791 	/* MCLK divisor mask = 0xe0 */
792 	snd_soc_update_bits(codec, WM8978_CLOCKING, 0xe0, best << 5);
793 
794 	snd_soc_write(codec, WM8978_AUDIO_INTERFACE, iface_ctl);
795 	snd_soc_write(codec, WM8978_ADDITIONAL_CONTROL, add_ctl);
796 
797 	if (wm8978->sysclk != current_clk_id) {
798 		if (wm8978->sysclk == WM8978_PLL)
799 			/* Run CODEC from PLL instead of MCLK */
800 			snd_soc_update_bits(codec, WM8978_CLOCKING,
801 					    0x100, 0x100);
802 		else
803 			/* Clock CODEC directly from MCLK */
804 			snd_soc_update_bits(codec, WM8978_CLOCKING, 0x100, 0);
805 	}
806 
807 	return 0;
808 }
809 
810 static int wm8978_mute(struct snd_soc_dai *dai, int mute)
811 {
812 	struct snd_soc_codec *codec = dai->codec;
813 
814 	dev_dbg(codec->dev, "%s: %d\n", __func__, mute);
815 
816 	if (mute)
817 		snd_soc_update_bits(codec, WM8978_DAC_CONTROL, 0x40, 0x40);
818 	else
819 		snd_soc_update_bits(codec, WM8978_DAC_CONTROL, 0x40, 0);
820 
821 	return 0;
822 }
823 
824 static int wm8978_set_bias_level(struct snd_soc_codec *codec,
825 				 enum snd_soc_bias_level level)
826 {
827 	u16 power1 = snd_soc_read(codec, WM8978_POWER_MANAGEMENT_1) & ~3;
828 
829 	switch (level) {
830 	case SND_SOC_BIAS_ON:
831 	case SND_SOC_BIAS_PREPARE:
832 		power1 |= 1;  /* VMID 75k */
833 		snd_soc_write(codec, WM8978_POWER_MANAGEMENT_1, power1);
834 		break;
835 	case SND_SOC_BIAS_STANDBY:
836 		/* bit 3: enable bias, bit 2: enable I/O tie off buffer */
837 		power1 |= 0xc;
838 
839 		if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
840 			/* Initial cap charge at VMID 5k */
841 			snd_soc_write(codec, WM8978_POWER_MANAGEMENT_1,
842 				      power1 | 0x3);
843 			mdelay(100);
844 		}
845 
846 		power1 |= 0x2;  /* VMID 500k */
847 		snd_soc_write(codec, WM8978_POWER_MANAGEMENT_1, power1);
848 		break;
849 	case SND_SOC_BIAS_OFF:
850 		/* Preserve PLL - OPCLK may be used by someone */
851 		snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, ~0x20, 0);
852 		snd_soc_write(codec, WM8978_POWER_MANAGEMENT_2, 0);
853 		snd_soc_write(codec, WM8978_POWER_MANAGEMENT_3, 0);
854 		break;
855 	}
856 
857 	dev_dbg(codec->dev, "%s: %d, %x\n", __func__, level, power1);
858 
859 	codec->dapm.bias_level = level;
860 	return 0;
861 }
862 
863 #define WM8978_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
864 	SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
865 
866 static struct snd_soc_dai_ops wm8978_dai_ops = {
867 	.hw_params	= wm8978_hw_params,
868 	.digital_mute	= wm8978_mute,
869 	.set_fmt	= wm8978_set_dai_fmt,
870 	.set_clkdiv	= wm8978_set_dai_clkdiv,
871 	.set_sysclk	= wm8978_set_dai_sysclk,
872 };
873 
874 /* Also supports 12kHz */
875 static struct snd_soc_dai_driver wm8978_dai = {
876 	.name = "wm8978-hifi",
877 	.playback = {
878 		.stream_name = "Playback",
879 		.channels_min = 1,
880 		.channels_max = 2,
881 		.rates = SNDRV_PCM_RATE_8000_48000,
882 		.formats = WM8978_FORMATS,
883 	},
884 	.capture = {
885 		.stream_name = "Capture",
886 		.channels_min = 1,
887 		.channels_max = 2,
888 		.rates = SNDRV_PCM_RATE_8000_48000,
889 		.formats = WM8978_FORMATS,
890 	},
891 	.ops = &wm8978_dai_ops,
892 };
893 
894 static int wm8978_suspend(struct snd_soc_codec *codec, pm_message_t state)
895 {
896 	wm8978_set_bias_level(codec, SND_SOC_BIAS_OFF);
897 	/* Also switch PLL off */
898 	snd_soc_write(codec, WM8978_POWER_MANAGEMENT_1, 0);
899 
900 	return 0;
901 }
902 
903 static int wm8978_resume(struct snd_soc_codec *codec)
904 {
905 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
906 	int i;
907 	u16 *cache = codec->reg_cache;
908 
909 	/* Sync reg_cache with the hardware */
910 	for (i = 0; i < ARRAY_SIZE(wm8978_reg); i++) {
911 		if (i == WM8978_RESET)
912 			continue;
913 		if (cache[i] != wm8978_reg[i])
914 			snd_soc_write(codec, i, cache[i]);
915 	}
916 
917 	wm8978_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
918 
919 	if (wm8978->f_pllout)
920 		/* Switch PLL on */
921 		snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, 0x20, 0x20);
922 
923 	return 0;
924 }
925 
926 /*
927  * These registers contain an "update" bit - bit 8. This means, for example,
928  * that one can write new DAC digital volume for both channels, but only when
929  * the update bit is set, will also the volume be updated - simultaneously for
930  * both channels.
931  */
932 static const int update_reg[] = {
933 	WM8978_LEFT_DAC_DIGITAL_VOLUME,
934 	WM8978_RIGHT_DAC_DIGITAL_VOLUME,
935 	WM8978_LEFT_ADC_DIGITAL_VOLUME,
936 	WM8978_RIGHT_ADC_DIGITAL_VOLUME,
937 	WM8978_LEFT_INP_PGA_CONTROL,
938 	WM8978_RIGHT_INP_PGA_CONTROL,
939 	WM8978_LOUT1_HP_CONTROL,
940 	WM8978_ROUT1_HP_CONTROL,
941 	WM8978_LOUT2_SPK_CONTROL,
942 	WM8978_ROUT2_SPK_CONTROL,
943 };
944 
945 static int wm8978_probe(struct snd_soc_codec *codec)
946 {
947 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
948 	int ret = 0, i;
949 
950 	/*
951 	 * Set default system clock to PLL, it is more precise, this is also the
952 	 * default hardware setting
953 	 */
954 	wm8978->sysclk = WM8978_PLL;
955 	codec->control_data = wm8978->control_data;
956 	ret = snd_soc_codec_set_cache_io(codec, 7, 9, SND_SOC_I2C);
957 	if (ret < 0) {
958 		dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
959 		return ret;
960 	}
961 
962 	/*
963 	 * Set the update bit in all registers, that have one. This way all
964 	 * writes to those registers will also cause the update bit to be
965 	 * written.
966 	 */
967 	for (i = 0; i < ARRAY_SIZE(update_reg); i++)
968 		((u16 *)codec->reg_cache)[update_reg[i]] |= 0x100;
969 
970 	/* Reset the codec */
971 	ret = snd_soc_write(codec, WM8978_RESET, 0);
972 	if (ret < 0) {
973 		dev_err(codec->dev, "Failed to issue reset\n");
974 		return ret;
975 	}
976 
977 	wm8978_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
978 
979 	snd_soc_add_controls(codec, wm8978_snd_controls,
980 			     ARRAY_SIZE(wm8978_snd_controls));
981 	wm8978_add_widgets(codec);
982 
983 	return 0;
984 }
985 
986 /* power down chip */
987 static int wm8978_remove(struct snd_soc_codec *codec)
988 {
989 	wm8978_set_bias_level(codec, SND_SOC_BIAS_OFF);
990 	return 0;
991 }
992 
993 static struct snd_soc_codec_driver soc_codec_dev_wm8978 = {
994 	.probe =	wm8978_probe,
995 	.remove =	wm8978_remove,
996 	.suspend =	wm8978_suspend,
997 	.resume =	wm8978_resume,
998 	.set_bias_level = wm8978_set_bias_level,
999 	.reg_cache_size = ARRAY_SIZE(wm8978_reg),
1000 	.reg_word_size = sizeof(u16),
1001 	.reg_cache_default = wm8978_reg,
1002 };
1003 
1004 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
1005 static __devinit int wm8978_i2c_probe(struct i2c_client *i2c,
1006 				      const struct i2c_device_id *id)
1007 {
1008 	struct wm8978_priv *wm8978;
1009 	int ret;
1010 
1011 	wm8978 = kzalloc(sizeof(struct wm8978_priv), GFP_KERNEL);
1012 	if (wm8978 == NULL)
1013 		return -ENOMEM;
1014 
1015 	i2c_set_clientdata(i2c, wm8978);
1016 	wm8978->control_data = i2c;
1017 
1018 	ret = snd_soc_register_codec(&i2c->dev,
1019 			&soc_codec_dev_wm8978, &wm8978_dai, 1);
1020 	if (ret < 0)
1021 		kfree(wm8978);
1022 	return ret;
1023 }
1024 
1025 static __devexit int wm8978_i2c_remove(struct i2c_client *client)
1026 {
1027 	snd_soc_unregister_codec(&client->dev);
1028 	kfree(i2c_get_clientdata(client));
1029 	return 0;
1030 }
1031 
1032 static const struct i2c_device_id wm8978_i2c_id[] = {
1033 	{ "wm8978", 0 },
1034 	{ }
1035 };
1036 MODULE_DEVICE_TABLE(i2c, wm8978_i2c_id);
1037 
1038 static struct i2c_driver wm8978_i2c_driver = {
1039 	.driver = {
1040 		.name = "wm8978",
1041 		.owner = THIS_MODULE,
1042 	},
1043 	.probe =    wm8978_i2c_probe,
1044 	.remove =   __devexit_p(wm8978_i2c_remove),
1045 	.id_table = wm8978_i2c_id,
1046 };
1047 #endif
1048 
1049 static int __init wm8978_modinit(void)
1050 {
1051 	int ret = 0;
1052 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
1053 	ret = i2c_add_driver(&wm8978_i2c_driver);
1054 	if (ret != 0) {
1055 		printk(KERN_ERR "Failed to register WM8978 I2C driver: %d\n",
1056 		       ret);
1057 	}
1058 #endif
1059 	return ret;
1060 }
1061 module_init(wm8978_modinit);
1062 
1063 static void __exit wm8978_exit(void)
1064 {
1065 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
1066 	i2c_del_driver(&wm8978_i2c_driver);
1067 #endif
1068 }
1069 module_exit(wm8978_exit);
1070 
1071 MODULE_DESCRIPTION("ASoC WM8978 codec driver");
1072 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
1073 MODULE_LICENSE("GPL");
1074