1/*
2 * CS4270 ALSA SoC (ASoC) codec driver
3 *
4 * Author: Timur Tabi <timur@freescale.com>
5 *
6 * Copyright 2007-2009 Freescale Semiconductor, Inc.  This file is licensed
7 * under the terms of the GNU General Public License version 2.  This
8 * program is licensed "as is" without any warranty of any kind, whether
9 * express or implied.
10 *
11 * This is an ASoC device driver for the Cirrus Logic CS4270 codec.
12 *
13 * Current features/limitations:
14 *
15 * - Software mode is supported.  Stand-alone mode is not supported.
16 * - Only I2C is supported, not SPI
17 * - Support for master and slave mode
18 * - The machine driver's 'startup' function must call
19 *   cs4270_set_dai_sysclk() with the value of MCLK.
20 * - Only I2S and left-justified modes are supported
21 * - Power management is supported
22 */
23
24#include <linux/module.h>
25#include <linux/slab.h>
26#include <sound/core.h>
27#include <sound/soc.h>
28#include <sound/initval.h>
29#include <linux/i2c.h>
30#include <linux/delay.h>
31#include <linux/regulator/consumer.h>
32#include <linux/gpio/consumer.h>
33#include <linux/of_device.h>
34
35/*
36 * The codec isn't really big-endian or little-endian, since the I2S
37 * interface requires data to be sent serially with the MSbit first.
38 * However, to support BE and LE I2S devices, we specify both here.  That
39 * way, ALSA will always match the bit patterns.
40 */
41#define CS4270_FORMATS (SNDRV_PCM_FMTBIT_S8      | \
42			SNDRV_PCM_FMTBIT_S16_LE  | SNDRV_PCM_FMTBIT_S16_BE  | \
43			SNDRV_PCM_FMTBIT_S18_3LE | SNDRV_PCM_FMTBIT_S18_3BE | \
44			SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S20_3BE | \
45			SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S24_3BE | \
46			SNDRV_PCM_FMTBIT_S24_LE  | SNDRV_PCM_FMTBIT_S24_BE)
47
48/* CS4270 registers addresses */
49#define CS4270_CHIPID	0x01	/* Chip ID */
50#define CS4270_PWRCTL	0x02	/* Power Control */
51#define CS4270_MODE	0x03	/* Mode Control */
52#define CS4270_FORMAT	0x04	/* Serial Format, ADC/DAC Control */
53#define CS4270_TRANS	0x05	/* Transition Control */
54#define CS4270_MUTE	0x06	/* Mute Control */
55#define CS4270_VOLA	0x07	/* DAC Channel A Volume Control */
56#define CS4270_VOLB	0x08	/* DAC Channel B Volume Control */
57
58#define CS4270_FIRSTREG	0x01
59#define CS4270_LASTREG	0x08
60#define CS4270_NUMREGS	(CS4270_LASTREG - CS4270_FIRSTREG + 1)
61#define CS4270_I2C_INCR	0x80
62
63/* Bit masks for the CS4270 registers */
64#define CS4270_CHIPID_ID	0xF0
65#define CS4270_CHIPID_REV	0x0F
66#define CS4270_PWRCTL_FREEZE	0x80
67#define CS4270_PWRCTL_PDN_ADC	0x20
68#define CS4270_PWRCTL_PDN_DAC	0x02
69#define CS4270_PWRCTL_PDN	0x01
70#define CS4270_PWRCTL_PDN_ALL	\
71	(CS4270_PWRCTL_PDN_ADC | CS4270_PWRCTL_PDN_DAC | CS4270_PWRCTL_PDN)
72#define CS4270_MODE_SPEED_MASK	0x30
73#define CS4270_MODE_1X		0x00
74#define CS4270_MODE_2X		0x10
75#define CS4270_MODE_4X		0x20
76#define CS4270_MODE_SLAVE	0x30
77#define CS4270_MODE_DIV_MASK	0x0E
78#define CS4270_MODE_DIV1	0x00
79#define CS4270_MODE_DIV15	0x02
80#define CS4270_MODE_DIV2	0x04
81#define CS4270_MODE_DIV3	0x06
82#define CS4270_MODE_DIV4	0x08
83#define CS4270_MODE_POPGUARD	0x01
84#define CS4270_FORMAT_FREEZE_A	0x80
85#define CS4270_FORMAT_FREEZE_B	0x40
86#define CS4270_FORMAT_LOOPBACK	0x20
87#define CS4270_FORMAT_DAC_MASK	0x18
88#define CS4270_FORMAT_DAC_LJ	0x00
89#define CS4270_FORMAT_DAC_I2S	0x08
90#define CS4270_FORMAT_DAC_RJ16	0x18
91#define CS4270_FORMAT_DAC_RJ24	0x10
92#define CS4270_FORMAT_ADC_MASK	0x01
93#define CS4270_FORMAT_ADC_LJ	0x00
94#define CS4270_FORMAT_ADC_I2S	0x01
95#define CS4270_TRANS_ONE_VOL	0x80
96#define CS4270_TRANS_SOFT	0x40
97#define CS4270_TRANS_ZERO	0x20
98#define CS4270_TRANS_INV_ADC_A	0x08
99#define CS4270_TRANS_INV_ADC_B	0x10
100#define CS4270_TRANS_INV_DAC_A	0x02
101#define CS4270_TRANS_INV_DAC_B	0x04
102#define CS4270_TRANS_DEEMPH	0x01
103#define CS4270_MUTE_AUTO	0x20
104#define CS4270_MUTE_ADC_A	0x08
105#define CS4270_MUTE_ADC_B	0x10
106#define CS4270_MUTE_POLARITY	0x04
107#define CS4270_MUTE_DAC_A	0x01
108#define CS4270_MUTE_DAC_B	0x02
109
110/* Power-on default values for the registers
111 *
112 * This array contains the power-on default values of the registers, with the
113 * exception of the "CHIPID" register (01h).  The lower four bits of that
114 * register contain the hardware revision, so it is treated as volatile.
115 */
116static const struct reg_default cs4270_reg_defaults[] = {
117	{ 2, 0x00 },
118	{ 3, 0x30 },
119	{ 4, 0x00 },
120	{ 5, 0x60 },
121	{ 6, 0x20 },
122	{ 7, 0x00 },
123	{ 8, 0x00 },
124};
125
126static const char *supply_names[] = {
127	"va", "vd", "vlc"
128};
129
130/* Private data for the CS4270 */
131struct cs4270_private {
132	struct regmap *regmap;
133	unsigned int mclk; /* Input frequency of the MCLK pin */
134	unsigned int mode; /* The mode (I2S or left-justified) */
135	unsigned int slave_mode;
136	unsigned int manual_mute;
137
138	/* power domain regulators */
139	struct regulator_bulk_data supplies[ARRAY_SIZE(supply_names)];
140
141	/* reset gpio */
142	struct gpio_desc *reset_gpio;
143};
144
145static const struct snd_soc_dapm_widget cs4270_dapm_widgets[] = {
146SND_SOC_DAPM_INPUT("AINL"),
147SND_SOC_DAPM_INPUT("AINR"),
148
149SND_SOC_DAPM_OUTPUT("AOUTL"),
150SND_SOC_DAPM_OUTPUT("AOUTR"),
151};
152
153static const struct snd_soc_dapm_route cs4270_dapm_routes[] = {
154	{ "Capture", NULL, "AINL" },
155	{ "Capture", NULL, "AINR" },
156
157	{ "AOUTL", NULL, "Playback" },
158	{ "AOUTR", NULL, "Playback" },
159};
160
161/**
162 * struct cs4270_mode_ratios - clock ratio tables
163 * @ratio: the ratio of MCLK to the sample rate
164 * @speed_mode: the Speed Mode bits to set in the Mode Control register for
165 *              this ratio
166 * @mclk: the Ratio Select bits to set in the Mode Control register for this
167 *        ratio
168 *
169 * The data for this chart is taken from Table 5 of the CS4270 reference
170 * manual.
171 *
172 * This table is used to determine how to program the Mode Control register.
173 * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
174 * rates the CS4270 currently supports.
175 *
176 * @speed_mode is the corresponding bit pattern to be written to the
177 * MODE bits of the Mode Control Register
178 *
179 * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
180 * the Mode Control Register.
181 *
182 * In situations where a single ratio is represented by multiple speed
183 * modes, we favor the slowest speed.  E.g, for a ratio of 128, we pick
184 * double-speed instead of quad-speed.  However, the CS4270 errata states
185 * that divide-By-1.5 can cause failures, so we avoid that mode where
186 * possible.
187 *
188 * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
189 * work if Vd is 3.3V.  If this effects you, select the
190 * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
191 * never select any sample rates that require divide-by-1.5.
192 */
193struct cs4270_mode_ratios {
194	unsigned int ratio;
195	u8 speed_mode;
196	u8 mclk;
197};
198
199static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
200	{64, CS4270_MODE_4X, CS4270_MODE_DIV1},
201#ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
202	{96, CS4270_MODE_4X, CS4270_MODE_DIV15},
203#endif
204	{128, CS4270_MODE_2X, CS4270_MODE_DIV1},
205	{192, CS4270_MODE_4X, CS4270_MODE_DIV3},
206	{256, CS4270_MODE_1X, CS4270_MODE_DIV1},
207	{384, CS4270_MODE_2X, CS4270_MODE_DIV3},
208	{512, CS4270_MODE_1X, CS4270_MODE_DIV2},
209	{768, CS4270_MODE_1X, CS4270_MODE_DIV3},
210	{1024, CS4270_MODE_1X, CS4270_MODE_DIV4}
211};
212
213/* The number of MCLK/LRCK ratios supported by the CS4270 */
214#define NUM_MCLK_RATIOS		ARRAY_SIZE(cs4270_mode_ratios)
215
216static bool cs4270_reg_is_readable(struct device *dev, unsigned int reg)
217{
218	return (reg >= CS4270_FIRSTREG) && (reg <= CS4270_LASTREG);
219}
220
221static bool cs4270_reg_is_volatile(struct device *dev, unsigned int reg)
222{
223	/* Unreadable registers are considered volatile */
224	if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
225		return true;
226
227	return reg == CS4270_CHIPID;
228}
229
230/**
231 * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
232 * @codec_dai: the codec DAI
233 * @clk_id: the clock ID (ignored)
234 * @freq: the MCLK input frequency
235 * @dir: the clock direction (ignored)
236 *
237 * This function is used to tell the codec driver what the input MCLK
238 * frequency is.
239 *
240 * The value of MCLK is used to determine which sample rates are supported
241 * by the CS4270.  The ratio of MCLK / Fs must be equal to one of nine
242 * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
243 *
244 * This function calculates the nine ratios and determines which ones match
245 * a standard sample rate.  If there's a match, then it is added to the list
246 * of supported sample rates.
247 *
248 * This function must be called by the machine driver's 'startup' function,
249 * otherwise the list of supported sample rates will not be available in
250 * time for ALSA.
251 *
252 * For setups with variable MCLKs, pass 0 as 'freq' argument. This will cause
253 * theoretically possible sample rates to be enabled. Call it again with a
254 * proper value set one the external clock is set (most probably you would do
255 * that from a machine's driver 'hw_param' hook.
256 */
257static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
258				 int clk_id, unsigned int freq, int dir)
259{
260	struct snd_soc_component *component = codec_dai->component;
261	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
262
263	cs4270->mclk = freq;
264	return 0;
265}
266
267/**
268 * cs4270_set_dai_fmt - configure the codec for the selected audio format
269 * @codec_dai: the codec DAI
270 * @format: a SND_SOC_DAIFMT_x value indicating the data format
271 *
272 * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
273 * codec accordingly.
274 *
275 * Currently, this function only supports SND_SOC_DAIFMT_I2S and
276 * SND_SOC_DAIFMT_LEFT_J.  The CS4270 codec also supports right-justified
277 * data for playback only, but ASoC currently does not support different
278 * formats for playback vs. record.
279 */
280static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
281			      unsigned int format)
282{
283	struct snd_soc_component *component = codec_dai->component;
284	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
285
286	/* set DAI format */
287	switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
288	case SND_SOC_DAIFMT_I2S:
289	case SND_SOC_DAIFMT_LEFT_J:
290		cs4270->mode = format & SND_SOC_DAIFMT_FORMAT_MASK;
291		break;
292	default:
293		dev_err(component->dev, "invalid dai format\n");
294		return -EINVAL;
295	}
296
297	/* set master/slave audio interface */
298	switch (format & SND_SOC_DAIFMT_MASTER_MASK) {
299	case SND_SOC_DAIFMT_CBS_CFS:
300		cs4270->slave_mode = 1;
301		break;
302	case SND_SOC_DAIFMT_CBM_CFM:
303		cs4270->slave_mode = 0;
304		break;
305	default:
306		/* all other modes are unsupported by the hardware */
307		dev_err(component->dev, "Unknown master/slave configuration\n");
308		return -EINVAL;
309	}
310
311	return 0;
312}
313
314/**
315 * cs4270_hw_params - program the CS4270 with the given hardware parameters.
316 * @substream: the audio stream
317 * @params: the hardware parameters to set
318 * @dai: the SOC DAI (ignored)
319 *
320 * This function programs the hardware with the values provided.
321 * Specifically, the sample rate and the data format.
322 *
323 * The .ops functions are used to provide board-specific data, like input
324 * frequencies, to this driver.  This function takes that information,
325 * combines it with the hardware parameters provided, and programs the
326 * hardware accordingly.
327 */
328static int cs4270_hw_params(struct snd_pcm_substream *substream,
329			    struct snd_pcm_hw_params *params,
330			    struct snd_soc_dai *dai)
331{
332	struct snd_soc_component *component = dai->component;
333	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
334	int ret;
335	unsigned int i;
336	unsigned int rate;
337	unsigned int ratio;
338	int reg;
339
340	/* Figure out which MCLK/LRCK ratio to use */
341
342	rate = params_rate(params);	/* Sampling rate, in Hz */
343	ratio = cs4270->mclk / rate;	/* MCLK/LRCK ratio */
344
345	for (i = 0; i < NUM_MCLK_RATIOS; i++) {
346		if (cs4270_mode_ratios[i].ratio == ratio)
347			break;
348	}
349
350	if (i == NUM_MCLK_RATIOS) {
351		/* We did not find a matching ratio */
352		dev_err(component->dev, "could not find matching ratio\n");
353		return -EINVAL;
354	}
355
356	/* Set the sample rate */
357
358	reg = snd_soc_component_read(component, CS4270_MODE);
359	reg &= ~(CS4270_MODE_SPEED_MASK | CS4270_MODE_DIV_MASK);
360	reg |= cs4270_mode_ratios[i].mclk;
361
362	if (cs4270->slave_mode)
363		reg |= CS4270_MODE_SLAVE;
364	else
365		reg |= cs4270_mode_ratios[i].speed_mode;
366
367	ret = snd_soc_component_write(component, CS4270_MODE, reg);
368	if (ret < 0) {
369		dev_err(component->dev, "i2c write failed\n");
370		return ret;
371	}
372
373	/* Set the DAI format */
374
375	reg = snd_soc_component_read(component, CS4270_FORMAT);
376	reg &= ~(CS4270_FORMAT_DAC_MASK | CS4270_FORMAT_ADC_MASK);
377
378	switch (cs4270->mode) {
379	case SND_SOC_DAIFMT_I2S:
380		reg |= CS4270_FORMAT_DAC_I2S | CS4270_FORMAT_ADC_I2S;
381		break;
382	case SND_SOC_DAIFMT_LEFT_J:
383		reg |= CS4270_FORMAT_DAC_LJ | CS4270_FORMAT_ADC_LJ;
384		break;
385	default:
386		dev_err(component->dev, "unknown dai format\n");
387		return -EINVAL;
388	}
389
390	ret = snd_soc_component_write(component, CS4270_FORMAT, reg);
391	if (ret < 0) {
392		dev_err(component->dev, "i2c write failed\n");
393		return ret;
394	}
395
396	return ret;
397}
398
399/**
400 * cs4270_dai_mute - enable/disable the CS4270 external mute
401 * @dai: the SOC DAI
402 * @mute: 0 = disable mute, 1 = enable mute
403 *
404 * This function toggles the mute bits in the MUTE register.  The CS4270's
405 * mute capability is intended for external muting circuitry, so if the
406 * board does not have the MUTEA or MUTEB pins connected to such circuitry,
407 * then this function will do nothing.
408 */
409static int cs4270_dai_mute(struct snd_soc_dai *dai, int mute, int direction)
410{
411	struct snd_soc_component *component = dai->component;
412	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
413	int reg6;
414
415	reg6 = snd_soc_component_read(component, CS4270_MUTE);
416
417	if (mute)
418		reg6 |= CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B;
419	else {
420		reg6 &= ~(CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B);
421		reg6 |= cs4270->manual_mute;
422	}
423
424	return snd_soc_component_write(component, CS4270_MUTE, reg6);
425}
426
427/**
428 * cs4270_soc_put_mute - put callback for the 'Master Playback switch'
429 * 			 alsa control.
430 * @kcontrol: mixer control
431 * @ucontrol: control element information
432 *
433 * This function basically passes the arguments on to the generic
434 * snd_soc_put_volsw() function and saves the mute information in
435 * our private data structure. This is because we want to prevent
436 * cs4270_dai_mute() neglecting the user's decision to manually
437 * mute the codec's output.
438 *
439 * Returns 0 for success.
440 */
441static int cs4270_soc_put_mute(struct snd_kcontrol *kcontrol,
442				struct snd_ctl_elem_value *ucontrol)
443{
444	struct snd_soc_component *component = snd_soc_kcontrol_component(kcontrol);
445	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
446	int left = !ucontrol->value.integer.value[0];
447	int right = !ucontrol->value.integer.value[1];
448
449	cs4270->manual_mute = (left ? CS4270_MUTE_DAC_A : 0) |
450			      (right ? CS4270_MUTE_DAC_B : 0);
451
452	return snd_soc_put_volsw(kcontrol, ucontrol);
453}
454
455/* A list of non-DAPM controls that the CS4270 supports */
456static const struct snd_kcontrol_new cs4270_snd_controls[] = {
457	SOC_DOUBLE_R("Master Playback Volume",
458		CS4270_VOLA, CS4270_VOLB, 0, 0xFF, 1),
459	SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
460	SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
461	SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
462	SOC_SINGLE("De-emphasis filter", CS4270_TRANS, 0, 1, 0),
463	SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
464	SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
465	SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),
466	SOC_DOUBLE_EXT("Master Playback Switch", CS4270_MUTE, 0, 1, 1, 1,
467		snd_soc_get_volsw, cs4270_soc_put_mute),
468};
469
470static const struct snd_soc_dai_ops cs4270_dai_ops = {
471	.hw_params	= cs4270_hw_params,
472	.set_sysclk	= cs4270_set_dai_sysclk,
473	.set_fmt	= cs4270_set_dai_fmt,
474	.mute_stream	= cs4270_dai_mute,
475	.no_capture_mute = 1,
476};
477
478static struct snd_soc_dai_driver cs4270_dai = {
479	.name = "cs4270-hifi",
480	.playback = {
481		.stream_name = "Playback",
482		.channels_min = 2,
483		.channels_max = 2,
484		.rates = SNDRV_PCM_RATE_CONTINUOUS,
485		.rate_min = 4000,
486		.rate_max = 216000,
487		.formats = CS4270_FORMATS,
488	},
489	.capture = {
490		.stream_name = "Capture",
491		.channels_min = 2,
492		.channels_max = 2,
493		.rates = SNDRV_PCM_RATE_CONTINUOUS,
494		.rate_min = 4000,
495		.rate_max = 216000,
496		.formats = CS4270_FORMATS,
497	},
498	.ops = &cs4270_dai_ops,
499};
500
501/**
502 * cs4270_probe - ASoC probe function
503 * @component: ASoC component
504 *
505 * This function is called when ASoC has all the pieces it needs to
506 * instantiate a sound driver.
507 */
508static int cs4270_probe(struct snd_soc_component *component)
509{
510	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
511	int ret;
512
513	/* Disable auto-mute.  This feature appears to be buggy.  In some
514	 * situations, auto-mute will not deactivate when it should, so we want
515	 * this feature disabled by default.  An application (e.g. alsactl) can
516	 * re-enabled it by using the controls.
517	 */
518	ret = snd_soc_component_update_bits(component, CS4270_MUTE, CS4270_MUTE_AUTO, 0);
519	if (ret < 0) {
520		dev_err(component->dev, "i2c write failed\n");
521		return ret;
522	}
523
524	/* Disable automatic volume control.  The hardware enables, and it
525	 * causes volume change commands to be delayed, sometimes until after
526	 * playback has started.  An application (e.g. alsactl) can
527	 * re-enabled it by using the controls.
528	 */
529	ret = snd_soc_component_update_bits(component, CS4270_TRANS,
530		CS4270_TRANS_SOFT | CS4270_TRANS_ZERO, 0);
531	if (ret < 0) {
532		dev_err(component->dev, "i2c write failed\n");
533		return ret;
534	}
535
536	ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
537				    cs4270->supplies);
538
539	return ret;
540}
541
542/**
543 * cs4270_remove - ASoC remove function
544 * @component: ASoC component
545 *
546 * This function is the counterpart to cs4270_probe().
547 */
548static void cs4270_remove(struct snd_soc_component *component)
549{
550	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
551
552	regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
553};
554
555#ifdef CONFIG_PM
556
557/* This suspend/resume implementation can handle both - a simple standby
558 * where the codec remains powered, and a full suspend, where the voltage
559 * domain the codec is connected to is teared down and/or any other hardware
560 * reset condition is asserted.
561 *
562 * The codec's own power saving features are enabled in the suspend callback,
563 * and all registers are written back to the hardware when resuming.
564 */
565
566static int cs4270_soc_suspend(struct snd_soc_component *component)
567{
568	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
569	int reg, ret;
570
571	reg = snd_soc_component_read(component, CS4270_PWRCTL) | CS4270_PWRCTL_PDN_ALL;
572	if (reg < 0)
573		return reg;
574
575	ret = snd_soc_component_write(component, CS4270_PWRCTL, reg);
576	if (ret < 0)
577		return ret;
578
579	regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies),
580			       cs4270->supplies);
581
582	return 0;
583}
584
585static int cs4270_soc_resume(struct snd_soc_component *component)
586{
587	struct cs4270_private *cs4270 = snd_soc_component_get_drvdata(component);
588	int reg, ret;
589
590	ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
591				    cs4270->supplies);
592	if (ret != 0)
593		return ret;
594
595	/* In case the device was put to hard reset during sleep, we need to
596	 * wait 500ns here before any I2C communication. */
597	ndelay(500);
598
599	/* first restore the entire register cache ... */
600	regcache_sync(cs4270->regmap);
601
602	/* ... then disable the power-down bits */
603	reg = snd_soc_component_read(component, CS4270_PWRCTL);
604	reg &= ~CS4270_PWRCTL_PDN_ALL;
605
606	return snd_soc_component_write(component, CS4270_PWRCTL, reg);
607}
608#else
609#define cs4270_soc_suspend	NULL
610#define cs4270_soc_resume	NULL
611#endif /* CONFIG_PM */
612
613/*
614 * ASoC codec driver structure
615 */
616static const struct snd_soc_component_driver soc_component_device_cs4270 = {
617	.probe			= cs4270_probe,
618	.remove			= cs4270_remove,
619	.suspend		= cs4270_soc_suspend,
620	.resume			= cs4270_soc_resume,
621	.controls		= cs4270_snd_controls,
622	.num_controls		= ARRAY_SIZE(cs4270_snd_controls),
623	.dapm_widgets		= cs4270_dapm_widgets,
624	.num_dapm_widgets	= ARRAY_SIZE(cs4270_dapm_widgets),
625	.dapm_routes		= cs4270_dapm_routes,
626	.num_dapm_routes	= ARRAY_SIZE(cs4270_dapm_routes),
627	.idle_bias_on		= 1,
628	.use_pmdown_time	= 1,
629	.endianness		= 1,
630	.non_legacy_dai_naming	= 1,
631};
632
633/*
634 * cs4270_of_match - the device tree bindings
635 */
636static const struct of_device_id cs4270_of_match[] = {
637	{ .compatible = "cirrus,cs4270", },
638	{ }
639};
640MODULE_DEVICE_TABLE(of, cs4270_of_match);
641
642static const struct regmap_config cs4270_regmap = {
643	.reg_bits =		8,
644	.val_bits =		8,
645	.max_register =		CS4270_LASTREG,
646	.reg_defaults =		cs4270_reg_defaults,
647	.num_reg_defaults =	ARRAY_SIZE(cs4270_reg_defaults),
648	.cache_type =		REGCACHE_RBTREE,
649	.write_flag_mask =	CS4270_I2C_INCR,
650
651	.readable_reg =		cs4270_reg_is_readable,
652	.volatile_reg =		cs4270_reg_is_volatile,
653};
654
655/**
656 * cs4270_i2c_remove - deinitialize the I2C interface of the CS4270
657 * @i2c_client: the I2C client object
658 *
659 * This function puts the chip into low power mode when the i2c device
660 * is removed.
661 */
662static int cs4270_i2c_remove(struct i2c_client *i2c_client)
663{
664	struct cs4270_private *cs4270 = i2c_get_clientdata(i2c_client);
665
666	gpiod_set_value_cansleep(cs4270->reset_gpio, 0);
667
668	return 0;
669}
670
671/**
672 * cs4270_i2c_probe - initialize the I2C interface of the CS4270
673 * @i2c_client: the I2C client object
674 * @id: the I2C device ID (ignored)
675 *
676 * This function is called whenever the I2C subsystem finds a device that
677 * matches the device ID given via a prior call to i2c_add_driver().
678 */
679static int cs4270_i2c_probe(struct i2c_client *i2c_client,
680	const struct i2c_device_id *id)
681{
682	struct cs4270_private *cs4270;
683	unsigned int val;
684	int ret, i;
685
686	cs4270 = devm_kzalloc(&i2c_client->dev, sizeof(struct cs4270_private),
687			      GFP_KERNEL);
688	if (!cs4270)
689		return -ENOMEM;
690
691	/* get the power supply regulators */
692	for (i = 0; i < ARRAY_SIZE(supply_names); i++)
693		cs4270->supplies[i].supply = supply_names[i];
694
695	ret = devm_regulator_bulk_get(&i2c_client->dev,
696				      ARRAY_SIZE(cs4270->supplies),
697				      cs4270->supplies);
698	if (ret < 0)
699		return ret;
700
701	/* reset the device */
702	cs4270->reset_gpio = devm_gpiod_get_optional(&i2c_client->dev, "reset",
703						     GPIOD_OUT_LOW);
704	if (IS_ERR(cs4270->reset_gpio)) {
705		dev_dbg(&i2c_client->dev, "Error getting CS4270 reset GPIO\n");
706		return PTR_ERR(cs4270->reset_gpio);
707	}
708
709	if (cs4270->reset_gpio) {
710		dev_dbg(&i2c_client->dev, "Found reset GPIO\n");
711		gpiod_set_value_cansleep(cs4270->reset_gpio, 1);
712	}
713
714	/* Sleep 500ns before i2c communications */
715	ndelay(500);
716
717	cs4270->regmap = devm_regmap_init_i2c(i2c_client, &cs4270_regmap);
718	if (IS_ERR(cs4270->regmap))
719		return PTR_ERR(cs4270->regmap);
720
721	/* Verify that we have a CS4270 */
722	ret = regmap_read(cs4270->regmap, CS4270_CHIPID, &val);
723	if (ret < 0) {
724		dev_err(&i2c_client->dev, "failed to read i2c at addr %X\n",
725		       i2c_client->addr);
726		return ret;
727	}
728	/* The top four bits of the chip ID should be 1100. */
729	if ((val & 0xF0) != 0xC0) {
730		dev_err(&i2c_client->dev, "device at addr %X is not a CS4270\n",
731		       i2c_client->addr);
732		return -ENODEV;
733	}
734
735	dev_info(&i2c_client->dev, "found device at i2c address %X\n",
736		i2c_client->addr);
737	dev_info(&i2c_client->dev, "hardware revision %X\n", val & 0xF);
738
739	i2c_set_clientdata(i2c_client, cs4270);
740
741	ret = devm_snd_soc_register_component(&i2c_client->dev,
742			&soc_component_device_cs4270, &cs4270_dai, 1);
743	return ret;
744}
745
746/*
747 * cs4270_id - I2C device IDs supported by this driver
748 */
749static const struct i2c_device_id cs4270_id[] = {
750	{"cs4270", 0},
751	{}
752};
753MODULE_DEVICE_TABLE(i2c, cs4270_id);
754
755/*
756 * cs4270_i2c_driver - I2C device identification
757 *
758 * This structure tells the I2C subsystem how to identify and support a
759 * given I2C device type.
760 */
761static struct i2c_driver cs4270_i2c_driver = {
762	.driver = {
763		.name = "cs4270",
764		.of_match_table = cs4270_of_match,
765	},
766	.id_table = cs4270_id,
767	.probe = cs4270_i2c_probe,
768	.remove = cs4270_i2c_remove,
769};
770
771module_i2c_driver(cs4270_i2c_driver);
772
773MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
774MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
775MODULE_LICENSE("GPL");
776