xref: /linux/sound/soc/codecs/ak4535.c (revision d524dac9279b6a41ffdf7ff7958c577f2e387db6)
1 /*
2  * ak4535.c  --  AK4535 ALSA Soc Audio driver
3  *
4  * Copyright 2005 Openedhand Ltd.
5  *
6  * Author: Richard Purdie <richard@openedhand.com>
7  *
8  * Based on wm8753.c by Liam Girdwood
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/moduleparam.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 
29 #include "ak4535.h"
30 
31 #define AK4535_VERSION "0.3"
32 
33 /* codec private data */
34 struct ak4535_priv {
35 	unsigned int sysclk;
36 	enum snd_soc_control_type control_type;
37 	void *control_data;
38 };
39 
40 /*
41  * ak4535 register cache
42  */
43 static const u16 ak4535_reg[AK4535_CACHEREGNUM] = {
44     0x0000, 0x0080, 0x0000, 0x0003,
45     0x0002, 0x0000, 0x0011, 0x0001,
46     0x0000, 0x0040, 0x0036, 0x0010,
47     0x0000, 0x0000, 0x0057, 0x0000,
48 };
49 
50 /*
51  * read ak4535 register cache
52  */
53 static inline unsigned int ak4535_read_reg_cache(struct snd_soc_codec *codec,
54 	unsigned int reg)
55 {
56 	u16 *cache = codec->reg_cache;
57 	if (reg >= AK4535_CACHEREGNUM)
58 		return -1;
59 	return cache[reg];
60 }
61 
62 /*
63  * write ak4535 register cache
64  */
65 static inline void ak4535_write_reg_cache(struct snd_soc_codec *codec,
66 	u16 reg, unsigned int value)
67 {
68 	u16 *cache = codec->reg_cache;
69 	if (reg >= AK4535_CACHEREGNUM)
70 		return;
71 	cache[reg] = value;
72 }
73 
74 /*
75  * write to the AK4535 register space
76  */
77 static int ak4535_write(struct snd_soc_codec *codec, unsigned int reg,
78 	unsigned int value)
79 {
80 	u8 data[2];
81 
82 	/* data is
83 	 *   D15..D8 AK4535 register offset
84 	 *   D7...D0 register data
85 	 */
86 	data[0] = reg & 0xff;
87 	data[1] = value & 0xff;
88 
89 	ak4535_write_reg_cache(codec, reg, value);
90 	if (codec->hw_write(codec->control_data, data, 2) == 2)
91 		return 0;
92 	else
93 		return -EIO;
94 }
95 
96 static int ak4535_sync(struct snd_soc_codec *codec)
97 {
98 	u16 *cache = codec->reg_cache;
99 	int i, r = 0;
100 
101 	for (i = 0; i < AK4535_CACHEREGNUM; i++)
102 		r |= ak4535_write(codec, i, cache[i]);
103 
104 	return r;
105 };
106 
107 static const char *ak4535_mono_gain[] = {"+6dB", "-17dB"};
108 static const char *ak4535_mono_out[] = {"(L + R)/2", "Hi-Z"};
109 static const char *ak4535_hp_out[] = {"Stereo", "Mono"};
110 static const char *ak4535_deemp[] = {"44.1kHz", "Off", "48kHz", "32kHz"};
111 static const char *ak4535_mic_select[] = {"Internal", "External"};
112 
113 static const struct soc_enum ak4535_enum[] = {
114 	SOC_ENUM_SINGLE(AK4535_SIG1, 7, 2, ak4535_mono_gain),
115 	SOC_ENUM_SINGLE(AK4535_SIG1, 6, 2, ak4535_mono_out),
116 	SOC_ENUM_SINGLE(AK4535_MODE2, 2, 2, ak4535_hp_out),
117 	SOC_ENUM_SINGLE(AK4535_DAC, 0, 4, ak4535_deemp),
118 	SOC_ENUM_SINGLE(AK4535_MIC, 1, 2, ak4535_mic_select),
119 };
120 
121 static const struct snd_kcontrol_new ak4535_snd_controls[] = {
122 	SOC_SINGLE("ALC2 Switch", AK4535_SIG1, 1, 1, 0),
123 	SOC_ENUM("Mono 1 Output", ak4535_enum[1]),
124 	SOC_ENUM("Mono 1 Gain", ak4535_enum[0]),
125 	SOC_ENUM("Headphone Output", ak4535_enum[2]),
126 	SOC_ENUM("Playback Deemphasis", ak4535_enum[3]),
127 	SOC_SINGLE("Bass Volume", AK4535_DAC, 2, 3, 0),
128 	SOC_SINGLE("Mic Boost (+20dB) Switch", AK4535_MIC, 0, 1, 0),
129 	SOC_ENUM("Mic Select", ak4535_enum[4]),
130 	SOC_SINGLE("ALC Operation Time", AK4535_TIMER, 0, 3, 0),
131 	SOC_SINGLE("ALC Recovery Time", AK4535_TIMER, 2, 3, 0),
132 	SOC_SINGLE("ALC ZC Time", AK4535_TIMER, 4, 3, 0),
133 	SOC_SINGLE("ALC 1 Switch", AK4535_ALC1, 5, 1, 0),
134 	SOC_SINGLE("ALC 2 Switch", AK4535_ALC1, 6, 1, 0),
135 	SOC_SINGLE("ALC Volume", AK4535_ALC2, 0, 127, 0),
136 	SOC_SINGLE("Capture Volume", AK4535_PGA, 0, 127, 0),
137 	SOC_SINGLE("Left Playback Volume", AK4535_LATT, 0, 127, 1),
138 	SOC_SINGLE("Right Playback Volume", AK4535_RATT, 0, 127, 1),
139 	SOC_SINGLE("AUX Bypass Volume", AK4535_VOL, 0, 15, 0),
140 	SOC_SINGLE("Mic Sidetone Volume", AK4535_VOL, 4, 7, 0),
141 };
142 
143 /* Mono 1 Mixer */
144 static const struct snd_kcontrol_new ak4535_mono1_mixer_controls[] = {
145 	SOC_DAPM_SINGLE("Mic Sidetone Switch", AK4535_SIG1, 4, 1, 0),
146 	SOC_DAPM_SINGLE("Mono Playback Switch", AK4535_SIG1, 5, 1, 0),
147 };
148 
149 /* Stereo Mixer */
150 static const struct snd_kcontrol_new ak4535_stereo_mixer_controls[] = {
151 	SOC_DAPM_SINGLE("Mic Sidetone Switch", AK4535_SIG2, 4, 1, 0),
152 	SOC_DAPM_SINGLE("Playback Switch", AK4535_SIG2, 7, 1, 0),
153 	SOC_DAPM_SINGLE("Aux Bypass Switch", AK4535_SIG2, 5, 1, 0),
154 };
155 
156 /* Input Mixer */
157 static const struct snd_kcontrol_new ak4535_input_mixer_controls[] = {
158 	SOC_DAPM_SINGLE("Mic Capture Switch", AK4535_MIC, 2, 1, 0),
159 	SOC_DAPM_SINGLE("Aux Capture Switch", AK4535_MIC, 5, 1, 0),
160 };
161 
162 /* Input mux */
163 static const struct snd_kcontrol_new ak4535_input_mux_control =
164 	SOC_DAPM_ENUM("Input Select", ak4535_enum[4]);
165 
166 /* HP L switch */
167 static const struct snd_kcontrol_new ak4535_hpl_control =
168 	SOC_DAPM_SINGLE("Switch", AK4535_SIG2, 1, 1, 1);
169 
170 /* HP R switch */
171 static const struct snd_kcontrol_new ak4535_hpr_control =
172 	SOC_DAPM_SINGLE("Switch", AK4535_SIG2, 0, 1, 1);
173 
174 /* mono 2 switch */
175 static const struct snd_kcontrol_new ak4535_mono2_control =
176 	SOC_DAPM_SINGLE("Switch", AK4535_SIG1, 0, 1, 0);
177 
178 /* Line out switch */
179 static const struct snd_kcontrol_new ak4535_line_control =
180 	SOC_DAPM_SINGLE("Switch", AK4535_SIG2, 6, 1, 0);
181 
182 /* ak4535 dapm widgets */
183 static const struct snd_soc_dapm_widget ak4535_dapm_widgets[] = {
184 	SND_SOC_DAPM_MIXER("Stereo Mixer", SND_SOC_NOPM, 0, 0,
185 		&ak4535_stereo_mixer_controls[0],
186 		ARRAY_SIZE(ak4535_stereo_mixer_controls)),
187 	SND_SOC_DAPM_MIXER("Mono1 Mixer", SND_SOC_NOPM, 0, 0,
188 		&ak4535_mono1_mixer_controls[0],
189 		ARRAY_SIZE(ak4535_mono1_mixer_controls)),
190 	SND_SOC_DAPM_MIXER("Input Mixer", SND_SOC_NOPM, 0, 0,
191 		&ak4535_input_mixer_controls[0],
192 		ARRAY_SIZE(ak4535_input_mixer_controls)),
193 	SND_SOC_DAPM_MUX("Input Mux", SND_SOC_NOPM, 0, 0,
194 		&ak4535_input_mux_control),
195 	SND_SOC_DAPM_DAC("DAC", "Playback", AK4535_PM2, 0, 0),
196 	SND_SOC_DAPM_SWITCH("Mono 2 Enable", SND_SOC_NOPM, 0, 0,
197 		&ak4535_mono2_control),
198 	/* speaker powersave bit */
199 	SND_SOC_DAPM_PGA("Speaker Enable", AK4535_MODE2, 0, 0, NULL, 0),
200 	SND_SOC_DAPM_SWITCH("Line Out Enable", SND_SOC_NOPM, 0, 0,
201 		&ak4535_line_control),
202 	SND_SOC_DAPM_SWITCH("Left HP Enable", SND_SOC_NOPM, 0, 0,
203 		&ak4535_hpl_control),
204 	SND_SOC_DAPM_SWITCH("Right HP Enable", SND_SOC_NOPM, 0, 0,
205 		&ak4535_hpr_control),
206 	SND_SOC_DAPM_OUTPUT("LOUT"),
207 	SND_SOC_DAPM_OUTPUT("HPL"),
208 	SND_SOC_DAPM_OUTPUT("ROUT"),
209 	SND_SOC_DAPM_OUTPUT("HPR"),
210 	SND_SOC_DAPM_OUTPUT("SPP"),
211 	SND_SOC_DAPM_OUTPUT("SPN"),
212 	SND_SOC_DAPM_OUTPUT("MOUT1"),
213 	SND_SOC_DAPM_OUTPUT("MOUT2"),
214 	SND_SOC_DAPM_OUTPUT("MICOUT"),
215 	SND_SOC_DAPM_ADC("ADC", "Capture", AK4535_PM1, 0, 0),
216 	SND_SOC_DAPM_PGA("Spk Amp", AK4535_PM2, 3, 0, NULL, 0),
217 	SND_SOC_DAPM_PGA("HP R Amp", AK4535_PM2, 1, 0, NULL, 0),
218 	SND_SOC_DAPM_PGA("HP L Amp", AK4535_PM2, 2, 0, NULL, 0),
219 	SND_SOC_DAPM_PGA("Mic", AK4535_PM1, 1, 0, NULL, 0),
220 	SND_SOC_DAPM_PGA("Line Out", AK4535_PM1, 4, 0, NULL, 0),
221 	SND_SOC_DAPM_PGA("Mono Out", AK4535_PM1, 3, 0, NULL, 0),
222 	SND_SOC_DAPM_PGA("AUX In", AK4535_PM1, 2, 0, NULL, 0),
223 
224 	SND_SOC_DAPM_MICBIAS("Mic Int Bias", AK4535_MIC, 3, 0),
225 	SND_SOC_DAPM_MICBIAS("Mic Ext Bias", AK4535_MIC, 4, 0),
226 	SND_SOC_DAPM_INPUT("MICIN"),
227 	SND_SOC_DAPM_INPUT("MICEXT"),
228 	SND_SOC_DAPM_INPUT("AUX"),
229 	SND_SOC_DAPM_INPUT("MIN"),
230 	SND_SOC_DAPM_INPUT("AIN"),
231 };
232 
233 static const struct snd_soc_dapm_route audio_map[] = {
234 	/*stereo mixer */
235 	{"Stereo Mixer", "Playback Switch", "DAC"},
236 	{"Stereo Mixer", "Mic Sidetone Switch", "Mic"},
237 	{"Stereo Mixer", "Aux Bypass Switch", "AUX In"},
238 
239 	/* mono1 mixer */
240 	{"Mono1 Mixer", "Mic Sidetone Switch", "Mic"},
241 	{"Mono1 Mixer", "Mono Playback Switch", "DAC"},
242 
243 	/* Mic */
244 	{"Mic", NULL, "AIN"},
245 	{"Input Mux", "Internal", "Mic Int Bias"},
246 	{"Input Mux", "External", "Mic Ext Bias"},
247 	{"Mic Int Bias", NULL, "MICIN"},
248 	{"Mic Ext Bias", NULL, "MICEXT"},
249 	{"MICOUT", NULL, "Input Mux"},
250 
251 	/* line out */
252 	{"LOUT", NULL, "Line Out Enable"},
253 	{"ROUT", NULL, "Line Out Enable"},
254 	{"Line Out Enable", "Switch", "Line Out"},
255 	{"Line Out", NULL, "Stereo Mixer"},
256 
257 	/* mono1 out */
258 	{"MOUT1", NULL, "Mono Out"},
259 	{"Mono Out", NULL, "Mono1 Mixer"},
260 
261 	/* left HP */
262 	{"HPL", NULL, "Left HP Enable"},
263 	{"Left HP Enable", "Switch", "HP L Amp"},
264 	{"HP L Amp", NULL, "Stereo Mixer"},
265 
266 	/* right HP */
267 	{"HPR", NULL, "Right HP Enable"},
268 	{"Right HP Enable", "Switch", "HP R Amp"},
269 	{"HP R Amp", NULL, "Stereo Mixer"},
270 
271 	/* speaker */
272 	{"SPP", NULL, "Speaker Enable"},
273 	{"SPN", NULL, "Speaker Enable"},
274 	{"Speaker Enable", "Switch", "Spk Amp"},
275 	{"Spk Amp", NULL, "MIN"},
276 
277 	/* mono 2 */
278 	{"MOUT2", NULL, "Mono 2 Enable"},
279 	{"Mono 2 Enable", "Switch", "Stereo Mixer"},
280 
281 	/* Aux In */
282 	{"Aux In", NULL, "AUX"},
283 
284 	/* ADC */
285 	{"ADC", NULL, "Input Mixer"},
286 	{"Input Mixer", "Mic Capture Switch", "Mic"},
287 	{"Input Mixer", "Aux Capture Switch", "Aux In"},
288 };
289 
290 static int ak4535_add_widgets(struct snd_soc_codec *codec)
291 {
292 	struct snd_soc_dapm_context *dapm = &codec->dapm;
293 
294 	snd_soc_dapm_new_controls(dapm, ak4535_dapm_widgets,
295 				  ARRAY_SIZE(ak4535_dapm_widgets));
296 	snd_soc_dapm_add_routes(dapm, audio_map, ARRAY_SIZE(audio_map));
297 
298 	return 0;
299 }
300 
301 static int ak4535_set_dai_sysclk(struct snd_soc_dai *codec_dai,
302 	int clk_id, unsigned int freq, int dir)
303 {
304 	struct snd_soc_codec *codec = codec_dai->codec;
305 	struct ak4535_priv *ak4535 = snd_soc_codec_get_drvdata(codec);
306 
307 	ak4535->sysclk = freq;
308 	return 0;
309 }
310 
311 static int ak4535_hw_params(struct snd_pcm_substream *substream,
312 			    struct snd_pcm_hw_params *params,
313 			    struct snd_soc_dai *dai)
314 {
315 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
316 	struct snd_soc_codec *codec = rtd->codec;
317 	struct ak4535_priv *ak4535 = snd_soc_codec_get_drvdata(codec);
318 	u8 mode2 = ak4535_read_reg_cache(codec, AK4535_MODE2) & ~(0x3 << 5);
319 	int rate = params_rate(params), fs = 256;
320 
321 	if (rate)
322 		fs = ak4535->sysclk / rate;
323 
324 	/* set fs */
325 	switch (fs) {
326 	case 1024:
327 		mode2 |= (0x2 << 5);
328 		break;
329 	case 512:
330 		mode2 |= (0x1 << 5);
331 		break;
332 	case 256:
333 		break;
334 	}
335 
336 	/* set rate */
337 	ak4535_write(codec, AK4535_MODE2, mode2);
338 	return 0;
339 }
340 
341 static int ak4535_set_dai_fmt(struct snd_soc_dai *codec_dai,
342 		unsigned int fmt)
343 {
344 	struct snd_soc_codec *codec = codec_dai->codec;
345 	u8 mode1 = 0;
346 
347 	/* interface format */
348 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
349 	case SND_SOC_DAIFMT_I2S:
350 		mode1 = 0x0002;
351 		break;
352 	case SND_SOC_DAIFMT_LEFT_J:
353 		mode1 = 0x0001;
354 		break;
355 	default:
356 		return -EINVAL;
357 	}
358 
359 	/* use 32 fs for BCLK to save power */
360 	mode1 |= 0x4;
361 
362 	ak4535_write(codec, AK4535_MODE1, mode1);
363 	return 0;
364 }
365 
366 static int ak4535_mute(struct snd_soc_dai *dai, int mute)
367 {
368 	struct snd_soc_codec *codec = dai->codec;
369 	u16 mute_reg = ak4535_read_reg_cache(codec, AK4535_DAC);
370 	if (!mute)
371 		ak4535_write(codec, AK4535_DAC, mute_reg & ~0x20);
372 	else
373 		ak4535_write(codec, AK4535_DAC, mute_reg | 0x20);
374 	return 0;
375 }
376 
377 static int ak4535_set_bias_level(struct snd_soc_codec *codec,
378 	enum snd_soc_bias_level level)
379 {
380 	u16 i, mute_reg;
381 
382 	switch (level) {
383 	case SND_SOC_BIAS_ON:
384 		mute_reg = ak4535_read_reg_cache(codec, AK4535_DAC);
385 		ak4535_write(codec, AK4535_DAC, mute_reg & ~0x20);
386 		break;
387 	case SND_SOC_BIAS_PREPARE:
388 		mute_reg = ak4535_read_reg_cache(codec, AK4535_DAC);
389 		ak4535_write(codec, AK4535_DAC, mute_reg | 0x20);
390 		break;
391 	case SND_SOC_BIAS_STANDBY:
392 		i = ak4535_read_reg_cache(codec, AK4535_PM1);
393 		ak4535_write(codec, AK4535_PM1, i | 0x80);
394 		i = ak4535_read_reg_cache(codec, AK4535_PM2);
395 		ak4535_write(codec, AK4535_PM2, i & (~0x80));
396 		break;
397 	case SND_SOC_BIAS_OFF:
398 		i = ak4535_read_reg_cache(codec, AK4535_PM1);
399 		ak4535_write(codec, AK4535_PM1, i & (~0x80));
400 		break;
401 	}
402 	codec->dapm.bias_level = level;
403 	return 0;
404 }
405 
406 #define AK4535_RATES (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |\
407 		SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 |\
408 		SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000)
409 
410 static struct snd_soc_dai_ops ak4535_dai_ops = {
411 	.hw_params	= ak4535_hw_params,
412 	.set_fmt	= ak4535_set_dai_fmt,
413 	.digital_mute	= ak4535_mute,
414 	.set_sysclk	= ak4535_set_dai_sysclk,
415 };
416 
417 static struct snd_soc_dai_driver ak4535_dai = {
418 	.name = "ak4535-hifi",
419 	.playback = {
420 		.stream_name = "Playback",
421 		.channels_min = 1,
422 		.channels_max = 2,
423 		.rates = AK4535_RATES,
424 		.formats = SNDRV_PCM_FMTBIT_S16_LE,},
425 	.capture = {
426 		.stream_name = "Capture",
427 		.channels_min = 1,
428 		.channels_max = 2,
429 		.rates = AK4535_RATES,
430 		.formats = SNDRV_PCM_FMTBIT_S16_LE,},
431 	.ops = &ak4535_dai_ops,
432 };
433 
434 static int ak4535_suspend(struct snd_soc_codec *codec, pm_message_t state)
435 {
436 	ak4535_set_bias_level(codec, SND_SOC_BIAS_OFF);
437 	return 0;
438 }
439 
440 static int ak4535_resume(struct snd_soc_codec *codec)
441 {
442 	ak4535_sync(codec);
443 	ak4535_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
444 	return 0;
445 }
446 
447 static int ak4535_probe(struct snd_soc_codec *codec)
448 {
449 	struct ak4535_priv *ak4535 = snd_soc_codec_get_drvdata(codec);
450 
451 	printk(KERN_INFO "AK4535 Audio Codec %s", AK4535_VERSION);
452 
453 	codec->control_data = ak4535->control_data;
454 
455 	/* power on device */
456 	ak4535_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
457 
458 	snd_soc_add_controls(codec, ak4535_snd_controls,
459 				ARRAY_SIZE(ak4535_snd_controls));
460 	ak4535_add_widgets(codec);
461 
462 	return 0;
463 }
464 
465 /* power down chip */
466 static int ak4535_remove(struct snd_soc_codec *codec)
467 {
468 	ak4535_set_bias_level(codec, SND_SOC_BIAS_OFF);
469 	return 0;
470 }
471 
472 static struct snd_soc_codec_driver soc_codec_dev_ak4535 = {
473 	.probe =	ak4535_probe,
474 	.remove =	ak4535_remove,
475 	.suspend =	ak4535_suspend,
476 	.resume =	ak4535_resume,
477 	.read = ak4535_read_reg_cache,
478 	.write = ak4535_write,
479 	.set_bias_level = ak4535_set_bias_level,
480 	.reg_cache_size = ARRAY_SIZE(ak4535_reg),
481 	.reg_word_size = sizeof(u8),
482 	.reg_cache_default = ak4535_reg,
483 };
484 
485 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
486 static __devinit int ak4535_i2c_probe(struct i2c_client *i2c,
487 				      const struct i2c_device_id *id)
488 {
489 	struct ak4535_priv *ak4535;
490 	int ret;
491 
492 	ak4535 = kzalloc(sizeof(struct ak4535_priv), GFP_KERNEL);
493 	if (ak4535 == NULL)
494 		return -ENOMEM;
495 
496 	i2c_set_clientdata(i2c, ak4535);
497 	ak4535->control_data = i2c;
498 	ak4535->control_type = SND_SOC_I2C;
499 
500 	ret = snd_soc_register_codec(&i2c->dev,
501 			&soc_codec_dev_ak4535, &ak4535_dai, 1);
502 	if (ret < 0)
503 		kfree(ak4535);
504 	return ret;
505 }
506 
507 static __devexit int ak4535_i2c_remove(struct i2c_client *client)
508 {
509 	snd_soc_unregister_codec(&client->dev);
510 	kfree(i2c_get_clientdata(client));
511 	return 0;
512 }
513 
514 static const struct i2c_device_id ak4535_i2c_id[] = {
515 	{ "ak4535", 0 },
516 	{ }
517 };
518 MODULE_DEVICE_TABLE(i2c, ak4535_i2c_id);
519 
520 static struct i2c_driver ak4535_i2c_driver = {
521 	.driver = {
522 		.name = "ak4535-codec",
523 		.owner = THIS_MODULE,
524 	},
525 	.probe =    ak4535_i2c_probe,
526 	.remove =   __devexit_p(ak4535_i2c_remove),
527 	.id_table = ak4535_i2c_id,
528 };
529 #endif
530 
531 static int __init ak4535_modinit(void)
532 {
533 	int ret = 0;
534 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
535 	ret = i2c_add_driver(&ak4535_i2c_driver);
536 	if (ret != 0) {
537 		printk(KERN_ERR "Failed to register AK4535 I2C driver: %d\n",
538 		       ret);
539 	}
540 #endif
541 	return ret;
542 }
543 module_init(ak4535_modinit);
544 
545 static void __exit ak4535_exit(void)
546 {
547 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
548 	i2c_del_driver(&ak4535_i2c_driver);
549 #endif
550 }
551 module_exit(ak4535_exit);
552 
553 MODULE_DESCRIPTION("Soc AK4535 driver");
554 MODULE_AUTHOR("Richard Purdie");
555 MODULE_LICENSE("GPL");
556