xref: /openbmc/linux/sound/soc/codecs/wm8978.c (revision 565d76cb)
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 static const DECLARE_TLV_DB_SCALE(limiter_tlv, 0, 100, 0);
97 
98 static const struct snd_kcontrol_new wm8978_snd_controls[] = {
99 
100 	SOC_SINGLE("Digital Loopback Switch",
101 		WM8978_COMPANDING_CONTROL, 0, 1, 0),
102 
103 	SOC_ENUM("ADC Companding", adc_compand),
104 	SOC_ENUM("DAC Companding", dac_compand),
105 
106 	SOC_DOUBLE("DAC Inversion Switch", WM8978_DAC_CONTROL, 0, 1, 1, 0),
107 
108 	SOC_DOUBLE_R_TLV("PCM Volume",
109 		WM8978_LEFT_DAC_DIGITAL_VOLUME, WM8978_RIGHT_DAC_DIGITAL_VOLUME,
110 		0, 255, 0, digital_tlv),
111 
112 	SOC_SINGLE("High Pass Filter Switch", WM8978_ADC_CONTROL, 8, 1, 0),
113 	SOC_SINGLE("High Pass Cut Off", WM8978_ADC_CONTROL, 4, 7, 0),
114 	SOC_DOUBLE("ADC Inversion Switch", WM8978_ADC_CONTROL, 0, 1, 1, 0),
115 
116 	SOC_DOUBLE_R_TLV("ADC Volume",
117 		WM8978_LEFT_ADC_DIGITAL_VOLUME, WM8978_RIGHT_ADC_DIGITAL_VOLUME,
118 		0, 255, 0, digital_tlv),
119 
120 	SOC_ENUM("Equaliser Function", eqmode),
121 	SOC_ENUM("EQ1 Cut Off", eq1),
122 	SOC_SINGLE_TLV("EQ1 Volume", WM8978_EQ1,  0, 24, 1, eq_tlv),
123 
124 	SOC_ENUM("Equaliser EQ2 Bandwith", eq2bw),
125 	SOC_ENUM("EQ2 Cut Off", eq2),
126 	SOC_SINGLE_TLV("EQ2 Volume", WM8978_EQ2,  0, 24, 1, eq_tlv),
127 
128 	SOC_ENUM("Equaliser EQ3 Bandwith", eq3bw),
129 	SOC_ENUM("EQ3 Cut Off", eq3),
130 	SOC_SINGLE_TLV("EQ3 Volume", WM8978_EQ3,  0, 24, 1, eq_tlv),
131 
132 	SOC_ENUM("Equaliser EQ4 Bandwith", eq4bw),
133 	SOC_ENUM("EQ4 Cut Off", eq4),
134 	SOC_SINGLE_TLV("EQ4 Volume", WM8978_EQ4,  0, 24, 1, eq_tlv),
135 
136 	SOC_ENUM("EQ5 Cut Off", eq5),
137 	SOC_SINGLE_TLV("EQ5 Volume", WM8978_EQ5, 0, 24, 1, eq_tlv),
138 
139 	SOC_SINGLE("DAC Playback Limiter Switch",
140 		WM8978_DAC_LIMITER_1, 8, 1, 0),
141 	SOC_SINGLE("DAC Playback Limiter Decay",
142 		WM8978_DAC_LIMITER_1, 4, 15, 0),
143 	SOC_SINGLE("DAC Playback Limiter Attack",
144 		WM8978_DAC_LIMITER_1, 0, 15, 0),
145 
146 	SOC_SINGLE("DAC Playback Limiter Threshold",
147 		WM8978_DAC_LIMITER_2, 4, 7, 0),
148 	SOC_SINGLE_TLV("DAC Playback Limiter Volume",
149 		WM8978_DAC_LIMITER_2, 0, 12, 0, limiter_tlv),
150 
151 	SOC_ENUM("ALC Enable Switch", alc1),
152 	SOC_SINGLE("ALC Capture Min Gain", WM8978_ALC_CONTROL_1, 0, 7, 0),
153 	SOC_SINGLE("ALC Capture Max Gain", WM8978_ALC_CONTROL_1, 3, 7, 0),
154 
155 	SOC_SINGLE("ALC Capture Hold", WM8978_ALC_CONTROL_2, 4, 10, 0),
156 	SOC_SINGLE("ALC Capture Target", WM8978_ALC_CONTROL_2, 0, 15, 0),
157 
158 	SOC_ENUM("ALC Capture Mode", alc3),
159 	SOC_SINGLE("ALC Capture Decay", WM8978_ALC_CONTROL_3, 4, 10, 0),
160 	SOC_SINGLE("ALC Capture Attack", WM8978_ALC_CONTROL_3, 0, 10, 0),
161 
162 	SOC_SINGLE("ALC Capture Noise Gate Switch", WM8978_NOISE_GATE, 3, 1, 0),
163 	SOC_SINGLE("ALC Capture Noise Gate Threshold",
164 		WM8978_NOISE_GATE, 0, 7, 0),
165 
166 	SOC_DOUBLE_R("Capture PGA ZC Switch",
167 		WM8978_LEFT_INP_PGA_CONTROL, WM8978_RIGHT_INP_PGA_CONTROL,
168 		7, 1, 0),
169 
170 	/* OUT1 - Headphones */
171 	SOC_DOUBLE_R("Headphone Playback ZC Switch",
172 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL, 7, 1, 0),
173 
174 	SOC_DOUBLE_R_TLV("Headphone Playback Volume",
175 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL,
176 		0, 63, 0, spk_tlv),
177 
178 	/* OUT2 - Speakers */
179 	SOC_DOUBLE_R("Speaker Playback ZC Switch",
180 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL, 7, 1, 0),
181 
182 	SOC_DOUBLE_R_TLV("Speaker Playback Volume",
183 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL,
184 		0, 63, 0, spk_tlv),
185 
186 	/* OUT3/4 - Line Output */
187 	SOC_DOUBLE_R("Line Playback Switch",
188 		WM8978_OUT3_MIXER_CONTROL, WM8978_OUT4_MIXER_CONTROL, 6, 1, 1),
189 
190 	/* Mixer #3: Boost (Input) mixer */
191 	SOC_DOUBLE_R("PGA Boost (+20dB)",
192 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
193 		8, 1, 0),
194 	SOC_DOUBLE_R_TLV("L2/R2 Boost Volume",
195 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
196 		4, 7, 0, boost_tlv),
197 	SOC_DOUBLE_R_TLV("Aux Boost Volume",
198 		WM8978_LEFT_ADC_BOOST_CONTROL, WM8978_RIGHT_ADC_BOOST_CONTROL,
199 		0, 7, 0, boost_tlv),
200 
201 	/* Input PGA volume */
202 	SOC_DOUBLE_R_TLV("Input PGA Volume",
203 		WM8978_LEFT_INP_PGA_CONTROL, WM8978_RIGHT_INP_PGA_CONTROL,
204 		0, 63, 0, inpga_tlv),
205 
206 	/* Headphone */
207 	SOC_DOUBLE_R("Headphone Switch",
208 		WM8978_LOUT1_HP_CONTROL, WM8978_ROUT1_HP_CONTROL, 6, 1, 1),
209 
210 	/* Speaker */
211 	SOC_DOUBLE_R("Speaker Switch",
212 		WM8978_LOUT2_SPK_CONTROL, WM8978_ROUT2_SPK_CONTROL, 6, 1, 1),
213 
214 	/* DAC / ADC oversampling */
215 	SOC_SINGLE("DAC 128x Oversampling Switch", WM8978_DAC_CONTROL,
216 		   5, 1, 0),
217 	SOC_SINGLE("ADC 128x Oversampling Switch", WM8978_ADC_CONTROL,
218 		   5, 1, 0),
219 };
220 
221 /* Mixer #1: Output (OUT1, OUT2) Mixer: mix AUX, Input mixer output and DAC */
222 static const struct snd_kcontrol_new wm8978_left_out_mixer[] = {
223 	SOC_DAPM_SINGLE("Line Bypass Switch", WM8978_LEFT_MIXER_CONTROL, 1, 1, 0),
224 	SOC_DAPM_SINGLE("Aux Playback Switch", WM8978_LEFT_MIXER_CONTROL, 5, 1, 0),
225 	SOC_DAPM_SINGLE("PCM Playback Switch", WM8978_LEFT_MIXER_CONTROL, 0, 1, 0),
226 };
227 
228 static const struct snd_kcontrol_new wm8978_right_out_mixer[] = {
229 	SOC_DAPM_SINGLE("Line Bypass Switch", WM8978_RIGHT_MIXER_CONTROL, 1, 1, 0),
230 	SOC_DAPM_SINGLE("Aux Playback Switch", WM8978_RIGHT_MIXER_CONTROL, 5, 1, 0),
231 	SOC_DAPM_SINGLE("PCM Playback Switch", WM8978_RIGHT_MIXER_CONTROL, 0, 1, 0),
232 };
233 
234 /* OUT3/OUT4 Mixer not implemented */
235 
236 /* Mixer #2: Input PGA Mute */
237 static const struct snd_kcontrol_new wm8978_left_input_mixer[] = {
238 	SOC_DAPM_SINGLE("L2 Switch", WM8978_INPUT_CONTROL, 2, 1, 0),
239 	SOC_DAPM_SINGLE("MicN Switch", WM8978_INPUT_CONTROL, 1, 1, 0),
240 	SOC_DAPM_SINGLE("MicP Switch", WM8978_INPUT_CONTROL, 0, 1, 0),
241 };
242 static const struct snd_kcontrol_new wm8978_right_input_mixer[] = {
243 	SOC_DAPM_SINGLE("R2 Switch", WM8978_INPUT_CONTROL, 6, 1, 0),
244 	SOC_DAPM_SINGLE("MicN Switch", WM8978_INPUT_CONTROL, 5, 1, 0),
245 	SOC_DAPM_SINGLE("MicP Switch", WM8978_INPUT_CONTROL, 4, 1, 0),
246 };
247 
248 static const struct snd_soc_dapm_widget wm8978_dapm_widgets[] = {
249 	SND_SOC_DAPM_DAC("Left DAC", "Left HiFi Playback",
250 			 WM8978_POWER_MANAGEMENT_3, 0, 0),
251 	SND_SOC_DAPM_DAC("Right DAC", "Right HiFi Playback",
252 			 WM8978_POWER_MANAGEMENT_3, 1, 0),
253 	SND_SOC_DAPM_ADC("Left ADC", "Left HiFi Capture",
254 			 WM8978_POWER_MANAGEMENT_2, 0, 0),
255 	SND_SOC_DAPM_ADC("Right ADC", "Right HiFi Capture",
256 			 WM8978_POWER_MANAGEMENT_2, 1, 0),
257 
258 	/* Mixer #1: OUT1,2 */
259 	SOC_MIXER_ARRAY("Left Output Mixer", WM8978_POWER_MANAGEMENT_3,
260 			2, 0, wm8978_left_out_mixer),
261 	SOC_MIXER_ARRAY("Right Output Mixer", WM8978_POWER_MANAGEMENT_3,
262 			3, 0, wm8978_right_out_mixer),
263 
264 	SOC_MIXER_ARRAY("Left Input Mixer", WM8978_POWER_MANAGEMENT_2,
265 			2, 0, wm8978_left_input_mixer),
266 	SOC_MIXER_ARRAY("Right Input Mixer", WM8978_POWER_MANAGEMENT_2,
267 			3, 0, wm8978_right_input_mixer),
268 
269 	SND_SOC_DAPM_PGA("Left Boost Mixer", WM8978_POWER_MANAGEMENT_2,
270 			 4, 0, NULL, 0),
271 	SND_SOC_DAPM_PGA("Right Boost Mixer", WM8978_POWER_MANAGEMENT_2,
272 			 5, 0, NULL, 0),
273 
274 	SND_SOC_DAPM_PGA("Left Capture PGA", WM8978_LEFT_INP_PGA_CONTROL,
275 			 6, 1, NULL, 0),
276 	SND_SOC_DAPM_PGA("Right Capture PGA", WM8978_RIGHT_INP_PGA_CONTROL,
277 			 6, 1, NULL, 0),
278 
279 	SND_SOC_DAPM_PGA("Left Headphone Out", WM8978_POWER_MANAGEMENT_2,
280 			 7, 0, NULL, 0),
281 	SND_SOC_DAPM_PGA("Right Headphone Out", WM8978_POWER_MANAGEMENT_2,
282 			 8, 0, NULL, 0),
283 
284 	SND_SOC_DAPM_PGA("Left Speaker Out", WM8978_POWER_MANAGEMENT_3,
285 			 6, 0, NULL, 0),
286 	SND_SOC_DAPM_PGA("Right Speaker Out", WM8978_POWER_MANAGEMENT_3,
287 			 5, 0, NULL, 0),
288 
289 	SND_SOC_DAPM_MIXER("OUT4 VMID", WM8978_POWER_MANAGEMENT_3,
290 			   8, 0, NULL, 0),
291 
292 	SND_SOC_DAPM_MICBIAS("Mic Bias", WM8978_POWER_MANAGEMENT_1, 4, 0),
293 
294 	SND_SOC_DAPM_INPUT("LMICN"),
295 	SND_SOC_DAPM_INPUT("LMICP"),
296 	SND_SOC_DAPM_INPUT("RMICN"),
297 	SND_SOC_DAPM_INPUT("RMICP"),
298 	SND_SOC_DAPM_INPUT("LAUX"),
299 	SND_SOC_DAPM_INPUT("RAUX"),
300 	SND_SOC_DAPM_INPUT("L2"),
301 	SND_SOC_DAPM_INPUT("R2"),
302 	SND_SOC_DAPM_OUTPUT("LHP"),
303 	SND_SOC_DAPM_OUTPUT("RHP"),
304 	SND_SOC_DAPM_OUTPUT("LSPK"),
305 	SND_SOC_DAPM_OUTPUT("RSPK"),
306 };
307 
308 static const struct snd_soc_dapm_route audio_map[] = {
309 	/* Output mixer */
310 	{"Right Output Mixer", "PCM Playback Switch", "Right DAC"},
311 	{"Right Output Mixer", "Aux Playback Switch", "RAUX"},
312 	{"Right Output Mixer", "Line Bypass Switch", "Right Boost Mixer"},
313 
314 	{"Left Output Mixer", "PCM Playback Switch", "Left DAC"},
315 	{"Left Output Mixer", "Aux Playback Switch", "LAUX"},
316 	{"Left Output Mixer", "Line Bypass Switch", "Left Boost Mixer"},
317 
318 	/* Outputs */
319 	{"Right Headphone Out", NULL, "Right Output Mixer"},
320 	{"RHP", NULL, "Right Headphone Out"},
321 
322 	{"Left Headphone Out", NULL, "Left Output Mixer"},
323 	{"LHP", NULL, "Left Headphone Out"},
324 
325 	{"Right Speaker Out", NULL, "Right Output Mixer"},
326 	{"RSPK", NULL, "Right Speaker Out"},
327 
328 	{"Left Speaker Out", NULL, "Left Output Mixer"},
329 	{"LSPK", NULL, "Left Speaker Out"},
330 
331 	/* Boost Mixer */
332 	{"Right ADC", NULL, "Right Boost Mixer"},
333 
334 	{"Right Boost Mixer", NULL, "RAUX"},
335 	{"Right Boost Mixer", NULL, "Right Capture PGA"},
336 	{"Right Boost Mixer", NULL, "R2"},
337 
338 	{"Left ADC", NULL, "Left Boost Mixer"},
339 
340 	{"Left Boost Mixer", NULL, "LAUX"},
341 	{"Left Boost Mixer", NULL, "Left Capture PGA"},
342 	{"Left Boost Mixer", NULL, "L2"},
343 
344 	/* Input PGA */
345 	{"Right Capture PGA", NULL, "Right Input Mixer"},
346 	{"Left Capture PGA", NULL, "Left Input Mixer"},
347 
348 	{"Right Input Mixer", "R2 Switch", "R2"},
349 	{"Right Input Mixer", "MicN Switch", "RMICN"},
350 	{"Right Input Mixer", "MicP Switch", "RMICP"},
351 
352 	{"Left Input Mixer", "L2 Switch", "L2"},
353 	{"Left Input Mixer", "MicN Switch", "LMICN"},
354 	{"Left Input Mixer", "MicP Switch", "LMICP"},
355 };
356 
357 static int wm8978_add_widgets(struct snd_soc_codec *codec)
358 {
359 	struct snd_soc_dapm_context *dapm = &codec->dapm;
360 
361 	snd_soc_dapm_new_controls(dapm, wm8978_dapm_widgets,
362 				  ARRAY_SIZE(wm8978_dapm_widgets));
363 	/* set up the WM8978 audio map */
364 	snd_soc_dapm_add_routes(dapm, audio_map, ARRAY_SIZE(audio_map));
365 
366 	return 0;
367 }
368 
369 /* PLL divisors */
370 struct wm8978_pll_div {
371 	u32 k;
372 	u8 n;
373 	u8 div2;
374 };
375 
376 #define FIXED_PLL_SIZE (1 << 24)
377 
378 static void pll_factors(struct snd_soc_codec *codec,
379 		struct wm8978_pll_div *pll_div, unsigned int target, unsigned int source)
380 {
381 	u64 k_part;
382 	unsigned int k, n_div, n_mod;
383 
384 	n_div = target / source;
385 	if (n_div < 6) {
386 		source >>= 1;
387 		pll_div->div2 = 1;
388 		n_div = target / source;
389 	} else {
390 		pll_div->div2 = 0;
391 	}
392 
393 	if (n_div < 6 || n_div > 12)
394 		dev_warn(codec->dev,
395 			 "WM8978 N value exceeds recommended range! N = %u\n",
396 			 n_div);
397 
398 	pll_div->n = n_div;
399 	n_mod = target - source * n_div;
400 	k_part = FIXED_PLL_SIZE * (long long)n_mod + source / 2;
401 
402 	do_div(k_part, source);
403 
404 	k = k_part & 0xFFFFFFFF;
405 
406 	pll_div->k = k;
407 }
408 
409 /* MCLK dividers */
410 static const int mclk_numerator[]	= {1, 3, 2, 3, 4, 6, 8, 12};
411 static const int mclk_denominator[]	= {1, 2, 1, 1, 1, 1, 1, 1};
412 
413 /*
414  * find index >= idx, such that, for a given f_out,
415  * 3 * f_mclk / 4 <= f_PLLOUT < 13 * f_mclk / 4
416  * f_out can be f_256fs or f_opclk, currently only used for f_256fs. Can be
417  * generalised for f_opclk with suitable coefficient arrays, but currently
418  * the OPCLK divisor is calculated directly, not iteratively.
419  */
420 static int wm8978_enum_mclk(unsigned int f_out, unsigned int f_mclk,
421 			    unsigned int *f_pllout)
422 {
423 	int i;
424 
425 	for (i = 0; i < ARRAY_SIZE(mclk_numerator); i++) {
426 		unsigned int f_pllout_x4 = 4 * f_out * mclk_numerator[i] /
427 			mclk_denominator[i];
428 		if (3 * f_mclk <= f_pllout_x4 && f_pllout_x4 < 13 * f_mclk) {
429 			*f_pllout = f_pllout_x4 / 4;
430 			return i;
431 		}
432 	}
433 
434 	return -EINVAL;
435 }
436 
437 /*
438  * Calculate internal frequencies and dividers, according to Figure 40
439  * "PLL and Clock Select Circuit" in WM8978 datasheet Rev. 2.6
440  */
441 static int wm8978_configure_pll(struct snd_soc_codec *codec)
442 {
443 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
444 	struct wm8978_pll_div pll_div;
445 	unsigned int f_opclk = wm8978->f_opclk, f_mclk = wm8978->f_mclk,
446 		f_256fs = wm8978->f_256fs;
447 	unsigned int f2;
448 
449 	if (!f_mclk)
450 		return -EINVAL;
451 
452 	if (f_opclk) {
453 		unsigned int opclk_div;
454 		/* Cannot set up MCLK divider now, do later */
455 		wm8978->mclk_idx = -1;
456 
457 		/*
458 		 * The user needs OPCLK. Choose OPCLKDIV to put
459 		 * 6 <= R = f2 / f1 < 13, 1 <= OPCLKDIV <= 4.
460 		 * f_opclk = f_mclk * prescale * R / 4 / OPCLKDIV, where
461 		 * prescale = 1, or prescale = 2. Prescale is calculated inside
462 		 * pll_factors(). We have to select f_PLLOUT, such that
463 		 * f_mclk * 3 / 4 <= f_PLLOUT < f_mclk * 13 / 4. Must be
464 		 * f_mclk * 3 / 16 <= f_opclk < f_mclk * 13 / 4.
465 		 */
466 		if (16 * f_opclk < 3 * f_mclk || 4 * f_opclk >= 13 * f_mclk)
467 			return -EINVAL;
468 
469 		if (4 * f_opclk < 3 * f_mclk)
470 			/* Have to use OPCLKDIV */
471 			opclk_div = (3 * f_mclk / 4 + f_opclk - 1) / f_opclk;
472 		else
473 			opclk_div = 1;
474 
475 		dev_dbg(codec->dev, "%s: OPCLKDIV=%d\n", __func__, opclk_div);
476 
477 		snd_soc_update_bits(codec, WM8978_GPIO_CONTROL, 0x30,
478 				    (opclk_div - 1) << 4);
479 
480 		wm8978->f_pllout = f_opclk * opclk_div;
481 	} else if (f_256fs) {
482 		/*
483 		 * Not using OPCLK, but PLL is used for the codec, choose R:
484 		 * 6 <= R = f2 / f1 < 13, to put 1 <= MCLKDIV <= 12.
485 		 * f_256fs = f_mclk * prescale * R / 4 / MCLKDIV, where
486 		 * prescale = 1, or prescale = 2. Prescale is calculated inside
487 		 * pll_factors(). We have to select f_PLLOUT, such that
488 		 * f_mclk * 3 / 4 <= f_PLLOUT < f_mclk * 13 / 4. Must be
489 		 * f_mclk * 3 / 48 <= f_256fs < f_mclk * 13 / 4. This means MCLK
490 		 * must be 3.781MHz <= f_MCLK <= 32.768MHz
491 		 */
492 		int idx = wm8978_enum_mclk(f_256fs, f_mclk, &wm8978->f_pllout);
493 		if (idx < 0)
494 			return idx;
495 
496 		wm8978->mclk_idx = idx;
497 
498 		/* GPIO1 into default mode as input - before configuring PLL */
499 		snd_soc_update_bits(codec, WM8978_GPIO_CONTROL, 7, 0);
500 	} else {
501 		return -EINVAL;
502 	}
503 
504 	f2 = wm8978->f_pllout * 4;
505 
506 	dev_dbg(codec->dev, "%s: f_MCLK=%uHz, f_PLLOUT=%uHz\n", __func__,
507 		wm8978->f_mclk, wm8978->f_pllout);
508 
509 	pll_factors(codec, &pll_div, f2, wm8978->f_mclk);
510 
511 	dev_dbg(codec->dev, "%s: calculated PLL N=0x%x, K=0x%x, div2=%d\n",
512 		__func__, pll_div.n, pll_div.k, pll_div.div2);
513 
514 	/* Turn PLL off for configuration... */
515 	snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, 0x20, 0);
516 
517 	snd_soc_write(codec, WM8978_PLL_N, (pll_div.div2 << 4) | pll_div.n);
518 	snd_soc_write(codec, WM8978_PLL_K1, pll_div.k >> 18);
519 	snd_soc_write(codec, WM8978_PLL_K2, (pll_div.k >> 9) & 0x1ff);
520 	snd_soc_write(codec, WM8978_PLL_K3, pll_div.k & 0x1ff);
521 
522 	/* ...and on again */
523 	snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, 0x20, 0x20);
524 
525 	if (f_opclk)
526 		/* Output PLL (OPCLK) to GPIO1 */
527 		snd_soc_update_bits(codec, WM8978_GPIO_CONTROL, 7, 4);
528 
529 	return 0;
530 }
531 
532 /*
533  * Configure WM8978 clock dividers.
534  */
535 static int wm8978_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
536 				 int div_id, int div)
537 {
538 	struct snd_soc_codec *codec = codec_dai->codec;
539 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
540 	int ret = 0;
541 
542 	switch (div_id) {
543 	case WM8978_OPCLKRATE:
544 		wm8978->f_opclk = div;
545 
546 		if (wm8978->f_mclk)
547 			/*
548 			 * We know the MCLK frequency, the user has requested
549 			 * OPCLK, configure the PLL based on that and start it
550 			 * and OPCLK immediately. We will configure PLL to match
551 			 * user-requested OPCLK frquency as good as possible.
552 			 * In fact, it is likely, that matching the sampling
553 			 * rate, when it becomes known, is more important, and
554 			 * we will not be reconfiguring PLL then, because we
555 			 * must not interrupt OPCLK. But it should be fine,
556 			 * because typically the user will request OPCLK to run
557 			 * at 256fs or 512fs, and for these cases we will also
558 			 * find an exact MCLK divider configuration - it will
559 			 * be equal to or double the OPCLK divisor.
560 			 */
561 			ret = wm8978_configure_pll(codec);
562 		break;
563 	case WM8978_BCLKDIV:
564 		if (div & ~0x1c)
565 			return -EINVAL;
566 		snd_soc_update_bits(codec, WM8978_CLOCKING, 0x1c, div);
567 		break;
568 	default:
569 		return -EINVAL;
570 	}
571 
572 	dev_dbg(codec->dev, "%s: ID %d, value %u\n", __func__, div_id, div);
573 
574 	return ret;
575 }
576 
577 /*
578  * @freq:	when .set_pll() us not used, freq is codec MCLK input frequency
579  */
580 static int wm8978_set_dai_sysclk(struct snd_soc_dai *codec_dai, int clk_id,
581 				 unsigned int freq, int dir)
582 {
583 	struct snd_soc_codec *codec = codec_dai->codec;
584 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
585 	int ret = 0;
586 
587 	dev_dbg(codec->dev, "%s: ID %d, freq %u\n", __func__, clk_id, freq);
588 
589 	if (freq) {
590 		wm8978->f_mclk = freq;
591 
592 		/* Even if MCLK is used for system clock, might have to drive OPCLK */
593 		if (wm8978->f_opclk)
594 			ret = wm8978_configure_pll(codec);
595 
596 		/* Our sysclk is fixed to 256 * fs, will configure in .hw_params()  */
597 
598 		if (!ret)
599 			wm8978->sysclk = clk_id;
600 	}
601 
602 	if (wm8978->sysclk == WM8978_PLL && (!freq || clk_id == WM8978_MCLK)) {
603 		/* Clock CODEC directly from MCLK */
604 		snd_soc_update_bits(codec, WM8978_CLOCKING, 0x100, 0);
605 
606 		/* GPIO1 into default mode as input - before configuring PLL */
607 		snd_soc_update_bits(codec, WM8978_GPIO_CONTROL, 7, 0);
608 
609 		/* Turn off PLL */
610 		snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, 0x20, 0);
611 		wm8978->sysclk = WM8978_MCLK;
612 		wm8978->f_pllout = 0;
613 		wm8978->f_opclk = 0;
614 	}
615 
616 	return ret;
617 }
618 
619 /*
620  * Set ADC and Voice DAC format.
621  */
622 static int wm8978_set_dai_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
623 {
624 	struct snd_soc_codec *codec = codec_dai->codec;
625 	/*
626 	 * BCLK polarity mask = 0x100, LRC clock polarity mask = 0x80,
627 	 * Data Format mask = 0x18: all will be calculated anew
628 	 */
629 	u16 iface = snd_soc_read(codec, WM8978_AUDIO_INTERFACE) & ~0x198;
630 	u16 clk = snd_soc_read(codec, WM8978_CLOCKING);
631 
632 	dev_dbg(codec->dev, "%s\n", __func__);
633 
634 	/* set master/slave audio interface */
635 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
636 	case SND_SOC_DAIFMT_CBM_CFM:
637 		clk |= 1;
638 		break;
639 	case SND_SOC_DAIFMT_CBS_CFS:
640 		clk &= ~1;
641 		break;
642 	default:
643 		return -EINVAL;
644 	}
645 
646 	/* interface format */
647 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
648 	case SND_SOC_DAIFMT_I2S:
649 		iface |= 0x10;
650 		break;
651 	case SND_SOC_DAIFMT_RIGHT_J:
652 		break;
653 	case SND_SOC_DAIFMT_LEFT_J:
654 		iface |= 0x8;
655 		break;
656 	case SND_SOC_DAIFMT_DSP_A:
657 		iface |= 0x18;
658 		break;
659 	default:
660 		return -EINVAL;
661 	}
662 
663 	/* clock inversion */
664 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
665 	case SND_SOC_DAIFMT_NB_NF:
666 		break;
667 	case SND_SOC_DAIFMT_IB_IF:
668 		iface |= 0x180;
669 		break;
670 	case SND_SOC_DAIFMT_IB_NF:
671 		iface |= 0x100;
672 		break;
673 	case SND_SOC_DAIFMT_NB_IF:
674 		iface |= 0x80;
675 		break;
676 	default:
677 		return -EINVAL;
678 	}
679 
680 	snd_soc_write(codec, WM8978_AUDIO_INTERFACE, iface);
681 	snd_soc_write(codec, WM8978_CLOCKING, clk);
682 
683 	return 0;
684 }
685 
686 /*
687  * Set PCM DAI bit size and sample rate.
688  */
689 static int wm8978_hw_params(struct snd_pcm_substream *substream,
690 			    struct snd_pcm_hw_params *params,
691 			    struct snd_soc_dai *dai)
692 {
693 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
694 	struct snd_soc_codec *codec = rtd->codec;
695 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
696 	/* Word length mask = 0x60 */
697 	u16 iface_ctl = snd_soc_read(codec, WM8978_AUDIO_INTERFACE) & ~0x60;
698 	/* Sampling rate mask = 0xe (for filters) */
699 	u16 add_ctl = snd_soc_read(codec, WM8978_ADDITIONAL_CONTROL) & ~0xe;
700 	u16 clking = snd_soc_read(codec, WM8978_CLOCKING);
701 	enum wm8978_sysclk_src current_clk_id = clking & 0x100 ?
702 		WM8978_PLL : WM8978_MCLK;
703 	unsigned int f_sel, diff, diff_best = INT_MAX;
704 	int i, best = 0;
705 
706 	if (!wm8978->f_mclk)
707 		return -EINVAL;
708 
709 	/* bit size */
710 	switch (params_format(params)) {
711 	case SNDRV_PCM_FORMAT_S16_LE:
712 		break;
713 	case SNDRV_PCM_FORMAT_S20_3LE:
714 		iface_ctl |= 0x20;
715 		break;
716 	case SNDRV_PCM_FORMAT_S24_LE:
717 		iface_ctl |= 0x40;
718 		break;
719 	case SNDRV_PCM_FORMAT_S32_LE:
720 		iface_ctl |= 0x60;
721 		break;
722 	}
723 
724 	/* filter coefficient */
725 	switch (params_rate(params)) {
726 	case 8000:
727 		add_ctl |= 0x5 << 1;
728 		break;
729 	case 11025:
730 		add_ctl |= 0x4 << 1;
731 		break;
732 	case 16000:
733 		add_ctl |= 0x3 << 1;
734 		break;
735 	case 22050:
736 		add_ctl |= 0x2 << 1;
737 		break;
738 	case 32000:
739 		add_ctl |= 0x1 << 1;
740 		break;
741 	case 44100:
742 	case 48000:
743 		break;
744 	}
745 
746 	/* Sampling rate is known now, can configure the MCLK divider */
747 	wm8978->f_256fs = params_rate(params) * 256;
748 
749 	if (wm8978->sysclk == WM8978_MCLK) {
750 		wm8978->mclk_idx = -1;
751 		f_sel = wm8978->f_mclk;
752 	} else {
753 		if (!wm8978->f_pllout) {
754 			/* We only enter here, if OPCLK is not used */
755 			int ret = wm8978_configure_pll(codec);
756 			if (ret < 0)
757 				return ret;
758 		}
759 		f_sel = wm8978->f_pllout;
760 	}
761 
762 	if (wm8978->mclk_idx < 0) {
763 		/* Either MCLK is used directly, or OPCLK is used */
764 		if (f_sel < wm8978->f_256fs || f_sel > 12 * wm8978->f_256fs)
765 			return -EINVAL;
766 
767 		for (i = 0; i < ARRAY_SIZE(mclk_numerator); i++) {
768 			diff = abs(wm8978->f_256fs * 3 -
769 				   f_sel * 3 * mclk_denominator[i] / mclk_numerator[i]);
770 
771 			if (diff < diff_best) {
772 				diff_best = diff;
773 				best = i;
774 			}
775 
776 			if (!diff)
777 				break;
778 		}
779 	} else {
780 		/* OPCLK not used, codec driven by PLL */
781 		best = wm8978->mclk_idx;
782 		diff = 0;
783 	}
784 
785 	if (diff)
786 		dev_warn(codec->dev, "Imprecise sampling rate: %uHz%s\n",
787 			f_sel * mclk_denominator[best] / mclk_numerator[best] / 256,
788 			wm8978->sysclk == WM8978_MCLK ?
789 			", consider using PLL" : "");
790 
791 	dev_dbg(codec->dev, "%s: fmt %d, rate %u, MCLK divisor #%d\n", __func__,
792 		params_format(params), params_rate(params), best);
793 
794 	/* MCLK divisor mask = 0xe0 */
795 	snd_soc_update_bits(codec, WM8978_CLOCKING, 0xe0, best << 5);
796 
797 	snd_soc_write(codec, WM8978_AUDIO_INTERFACE, iface_ctl);
798 	snd_soc_write(codec, WM8978_ADDITIONAL_CONTROL, add_ctl);
799 
800 	if (wm8978->sysclk != current_clk_id) {
801 		if (wm8978->sysclk == WM8978_PLL)
802 			/* Run CODEC from PLL instead of MCLK */
803 			snd_soc_update_bits(codec, WM8978_CLOCKING,
804 					    0x100, 0x100);
805 		else
806 			/* Clock CODEC directly from MCLK */
807 			snd_soc_update_bits(codec, WM8978_CLOCKING, 0x100, 0);
808 	}
809 
810 	return 0;
811 }
812 
813 static int wm8978_mute(struct snd_soc_dai *dai, int mute)
814 {
815 	struct snd_soc_codec *codec = dai->codec;
816 
817 	dev_dbg(codec->dev, "%s: %d\n", __func__, mute);
818 
819 	if (mute)
820 		snd_soc_update_bits(codec, WM8978_DAC_CONTROL, 0x40, 0x40);
821 	else
822 		snd_soc_update_bits(codec, WM8978_DAC_CONTROL, 0x40, 0);
823 
824 	return 0;
825 }
826 
827 static int wm8978_set_bias_level(struct snd_soc_codec *codec,
828 				 enum snd_soc_bias_level level)
829 {
830 	u16 power1 = snd_soc_read(codec, WM8978_POWER_MANAGEMENT_1) & ~3;
831 
832 	switch (level) {
833 	case SND_SOC_BIAS_ON:
834 	case SND_SOC_BIAS_PREPARE:
835 		power1 |= 1;  /* VMID 75k */
836 		snd_soc_write(codec, WM8978_POWER_MANAGEMENT_1, power1);
837 		break;
838 	case SND_SOC_BIAS_STANDBY:
839 		/* bit 3: enable bias, bit 2: enable I/O tie off buffer */
840 		power1 |= 0xc;
841 
842 		if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
843 			/* Initial cap charge at VMID 5k */
844 			snd_soc_write(codec, WM8978_POWER_MANAGEMENT_1,
845 				      power1 | 0x3);
846 			mdelay(100);
847 		}
848 
849 		power1 |= 0x2;  /* VMID 500k */
850 		snd_soc_write(codec, WM8978_POWER_MANAGEMENT_1, power1);
851 		break;
852 	case SND_SOC_BIAS_OFF:
853 		/* Preserve PLL - OPCLK may be used by someone */
854 		snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, ~0x20, 0);
855 		snd_soc_write(codec, WM8978_POWER_MANAGEMENT_2, 0);
856 		snd_soc_write(codec, WM8978_POWER_MANAGEMENT_3, 0);
857 		break;
858 	}
859 
860 	dev_dbg(codec->dev, "%s: %d, %x\n", __func__, level, power1);
861 
862 	codec->dapm.bias_level = level;
863 	return 0;
864 }
865 
866 #define WM8978_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
867 	SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
868 
869 static struct snd_soc_dai_ops wm8978_dai_ops = {
870 	.hw_params	= wm8978_hw_params,
871 	.digital_mute	= wm8978_mute,
872 	.set_fmt	= wm8978_set_dai_fmt,
873 	.set_clkdiv	= wm8978_set_dai_clkdiv,
874 	.set_sysclk	= wm8978_set_dai_sysclk,
875 };
876 
877 /* Also supports 12kHz */
878 static struct snd_soc_dai_driver wm8978_dai = {
879 	.name = "wm8978-hifi",
880 	.playback = {
881 		.stream_name = "Playback",
882 		.channels_min = 1,
883 		.channels_max = 2,
884 		.rates = SNDRV_PCM_RATE_8000_48000,
885 		.formats = WM8978_FORMATS,
886 	},
887 	.capture = {
888 		.stream_name = "Capture",
889 		.channels_min = 1,
890 		.channels_max = 2,
891 		.rates = SNDRV_PCM_RATE_8000_48000,
892 		.formats = WM8978_FORMATS,
893 	},
894 	.ops = &wm8978_dai_ops,
895 };
896 
897 static int wm8978_suspend(struct snd_soc_codec *codec, pm_message_t state)
898 {
899 	wm8978_set_bias_level(codec, SND_SOC_BIAS_OFF);
900 	/* Also switch PLL off */
901 	snd_soc_write(codec, WM8978_POWER_MANAGEMENT_1, 0);
902 
903 	return 0;
904 }
905 
906 static int wm8978_resume(struct snd_soc_codec *codec)
907 {
908 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
909 	int i;
910 	u16 *cache = codec->reg_cache;
911 
912 	/* Sync reg_cache with the hardware */
913 	for (i = 0; i < ARRAY_SIZE(wm8978_reg); i++) {
914 		if (i == WM8978_RESET)
915 			continue;
916 		if (cache[i] != wm8978_reg[i])
917 			snd_soc_write(codec, i, cache[i]);
918 	}
919 
920 	wm8978_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
921 
922 	if (wm8978->f_pllout)
923 		/* Switch PLL on */
924 		snd_soc_update_bits(codec, WM8978_POWER_MANAGEMENT_1, 0x20, 0x20);
925 
926 	return 0;
927 }
928 
929 /*
930  * These registers contain an "update" bit - bit 8. This means, for example,
931  * that one can write new DAC digital volume for both channels, but only when
932  * the update bit is set, will also the volume be updated - simultaneously for
933  * both channels.
934  */
935 static const int update_reg[] = {
936 	WM8978_LEFT_DAC_DIGITAL_VOLUME,
937 	WM8978_RIGHT_DAC_DIGITAL_VOLUME,
938 	WM8978_LEFT_ADC_DIGITAL_VOLUME,
939 	WM8978_RIGHT_ADC_DIGITAL_VOLUME,
940 	WM8978_LEFT_INP_PGA_CONTROL,
941 	WM8978_RIGHT_INP_PGA_CONTROL,
942 	WM8978_LOUT1_HP_CONTROL,
943 	WM8978_ROUT1_HP_CONTROL,
944 	WM8978_LOUT2_SPK_CONTROL,
945 	WM8978_ROUT2_SPK_CONTROL,
946 };
947 
948 static int wm8978_probe(struct snd_soc_codec *codec)
949 {
950 	struct wm8978_priv *wm8978 = snd_soc_codec_get_drvdata(codec);
951 	int ret = 0, i;
952 
953 	/*
954 	 * Set default system clock to PLL, it is more precise, this is also the
955 	 * default hardware setting
956 	 */
957 	wm8978->sysclk = WM8978_PLL;
958 	codec->control_data = wm8978->control_data;
959 	ret = snd_soc_codec_set_cache_io(codec, 7, 9, SND_SOC_I2C);
960 	if (ret < 0) {
961 		dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
962 		return ret;
963 	}
964 
965 	/*
966 	 * Set the update bit in all registers, that have one. This way all
967 	 * writes to those registers will also cause the update bit to be
968 	 * written.
969 	 */
970 	for (i = 0; i < ARRAY_SIZE(update_reg); i++)
971 		snd_soc_update_bits(codec, update_reg[i], 0x100, 0x100);
972 
973 	/* Reset the codec */
974 	ret = snd_soc_write(codec, WM8978_RESET, 0);
975 	if (ret < 0) {
976 		dev_err(codec->dev, "Failed to issue reset\n");
977 		return ret;
978 	}
979 
980 	wm8978_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
981 
982 	snd_soc_add_controls(codec, wm8978_snd_controls,
983 			     ARRAY_SIZE(wm8978_snd_controls));
984 	wm8978_add_widgets(codec);
985 
986 	return 0;
987 }
988 
989 /* power down chip */
990 static int wm8978_remove(struct snd_soc_codec *codec)
991 {
992 	wm8978_set_bias_level(codec, SND_SOC_BIAS_OFF);
993 	return 0;
994 }
995 
996 static struct snd_soc_codec_driver soc_codec_dev_wm8978 = {
997 	.probe =	wm8978_probe,
998 	.remove =	wm8978_remove,
999 	.suspend =	wm8978_suspend,
1000 	.resume =	wm8978_resume,
1001 	.set_bias_level = wm8978_set_bias_level,
1002 	.reg_cache_size = ARRAY_SIZE(wm8978_reg),
1003 	.reg_word_size = sizeof(u16),
1004 	.reg_cache_default = wm8978_reg,
1005 };
1006 
1007 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
1008 static __devinit int wm8978_i2c_probe(struct i2c_client *i2c,
1009 				      const struct i2c_device_id *id)
1010 {
1011 	struct wm8978_priv *wm8978;
1012 	int ret;
1013 
1014 	wm8978 = kzalloc(sizeof(struct wm8978_priv), GFP_KERNEL);
1015 	if (wm8978 == NULL)
1016 		return -ENOMEM;
1017 
1018 	i2c_set_clientdata(i2c, wm8978);
1019 	wm8978->control_data = i2c;
1020 
1021 	ret = snd_soc_register_codec(&i2c->dev,
1022 			&soc_codec_dev_wm8978, &wm8978_dai, 1);
1023 	if (ret < 0)
1024 		kfree(wm8978);
1025 	return ret;
1026 }
1027 
1028 static __devexit int wm8978_i2c_remove(struct i2c_client *client)
1029 {
1030 	snd_soc_unregister_codec(&client->dev);
1031 	kfree(i2c_get_clientdata(client));
1032 	return 0;
1033 }
1034 
1035 static const struct i2c_device_id wm8978_i2c_id[] = {
1036 	{ "wm8978", 0 },
1037 	{ }
1038 };
1039 MODULE_DEVICE_TABLE(i2c, wm8978_i2c_id);
1040 
1041 static struct i2c_driver wm8978_i2c_driver = {
1042 	.driver = {
1043 		.name = "wm8978",
1044 		.owner = THIS_MODULE,
1045 	},
1046 	.probe =    wm8978_i2c_probe,
1047 	.remove =   __devexit_p(wm8978_i2c_remove),
1048 	.id_table = wm8978_i2c_id,
1049 };
1050 #endif
1051 
1052 static int __init wm8978_modinit(void)
1053 {
1054 	int ret = 0;
1055 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
1056 	ret = i2c_add_driver(&wm8978_i2c_driver);
1057 	if (ret != 0) {
1058 		printk(KERN_ERR "Failed to register WM8978 I2C driver: %d\n",
1059 		       ret);
1060 	}
1061 #endif
1062 	return ret;
1063 }
1064 module_init(wm8978_modinit);
1065 
1066 static void __exit wm8978_exit(void)
1067 {
1068 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
1069 	i2c_del_driver(&wm8978_i2c_driver);
1070 #endif
1071 }
1072 module_exit(wm8978_exit);
1073 
1074 MODULE_DESCRIPTION("ASoC WM8978 codec driver");
1075 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
1076 MODULE_LICENSE("GPL");
1077