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/of_device.h>
33 #include <linux/of_gpio.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 */
116 static 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
126 static const char *supply_names[] = {
127 "va", "vd", "vlc"
128 };
129
130 /* Private data for the CS4270 */
131 struct 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
142 static const struct snd_soc_dapm_widget cs4270_dapm_widgets[] = {
143 SND_SOC_DAPM_INPUT("AINL"),
144 SND_SOC_DAPM_INPUT("AINR"),
145
146 SND_SOC_DAPM_OUTPUT("AOUTL"),
147 SND_SOC_DAPM_OUTPUT("AOUTR"),
148 };
149
150 static const struct snd_soc_dapm_route cs4270_dapm_routes[] = {
151 { "Capture", NULL, "AINL" },
152 { "Capture", NULL, "AINR" },
153
154 { "AOUTL", NULL, "Playback" },
155 { "AOUTR", NULL, "Playback" },
156 };
157
158 /**
159 * struct cs4270_mode_ratios - clock ratio tables
160 * @ratio: the ratio of MCLK to the sample rate
161 * @speed_mode: the Speed Mode bits to set in the Mode Control register for
162 * this ratio
163 * @mclk: the Ratio Select bits to set in the Mode Control register for this
164 * ratio
165 *
166 * The data for this chart is taken from Table 5 of the CS4270 reference
167 * manual.
168 *
169 * This table is used to determine how to program the Mode Control register.
170 * It is also used by cs4270_set_dai_sysclk() to tell ALSA which sampling
171 * rates the CS4270 currently supports.
172 *
173 * @speed_mode is the corresponding bit pattern to be written to the
174 * MODE bits of the Mode Control Register
175 *
176 * @mclk is the corresponding bit pattern to be wirten to the MCLK bits of
177 * the Mode Control Register.
178 *
179 * In situations where a single ratio is represented by multiple speed
180 * modes, we favor the slowest speed. E.g, for a ratio of 128, we pick
181 * double-speed instead of quad-speed. However, the CS4270 errata states
182 * that divide-By-1.5 can cause failures, so we avoid that mode where
183 * possible.
184 *
185 * Errata: There is an errata for the CS4270 where divide-by-1.5 does not
186 * work if Vd is 3.3V. If this effects you, select the
187 * CONFIG_SND_SOC_CS4270_VD33_ERRATA Kconfig option, and the driver will
188 * never select any sample rates that require divide-by-1.5.
189 */
190 struct cs4270_mode_ratios {
191 unsigned int ratio;
192 u8 speed_mode;
193 u8 mclk;
194 };
195
196 static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
197 {64, CS4270_MODE_4X, CS4270_MODE_DIV1},
198 #ifndef CONFIG_SND_SOC_CS4270_VD33_ERRATA
199 {96, CS4270_MODE_4X, CS4270_MODE_DIV15},
200 #endif
201 {128, CS4270_MODE_2X, CS4270_MODE_DIV1},
202 {192, CS4270_MODE_4X, CS4270_MODE_DIV3},
203 {256, CS4270_MODE_1X, CS4270_MODE_DIV1},
204 {384, CS4270_MODE_2X, CS4270_MODE_DIV3},
205 {512, CS4270_MODE_1X, CS4270_MODE_DIV2},
206 {768, CS4270_MODE_1X, CS4270_MODE_DIV3},
207 {1024, CS4270_MODE_1X, CS4270_MODE_DIV4}
208 };
209
210 /* The number of MCLK/LRCK ratios supported by the CS4270 */
211 #define NUM_MCLK_RATIOS ARRAY_SIZE(cs4270_mode_ratios)
212
cs4270_reg_is_readable(struct device * dev,unsigned int reg)213 static bool cs4270_reg_is_readable(struct device *dev, unsigned int reg)
214 {
215 return (reg >= CS4270_FIRSTREG) && (reg <= CS4270_LASTREG);
216 }
217
cs4270_reg_is_volatile(struct device * dev,unsigned int reg)218 static bool cs4270_reg_is_volatile(struct device *dev, unsigned int reg)
219 {
220 /* Unreadable registers are considered volatile */
221 if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
222 return 1;
223
224 return reg == CS4270_CHIPID;
225 }
226
227 /**
228 * cs4270_set_dai_sysclk - determine the CS4270 samples rates.
229 * @codec_dai: the codec DAI
230 * @clk_id: the clock ID (ignored)
231 * @freq: the MCLK input frequency
232 * @dir: the clock direction (ignored)
233 *
234 * This function is used to tell the codec driver what the input MCLK
235 * frequency is.
236 *
237 * The value of MCLK is used to determine which sample rates are supported
238 * by the CS4270. The ratio of MCLK / Fs must be equal to one of nine
239 * supported values - 64, 96, 128, 192, 256, 384, 512, 768, and 1024.
240 *
241 * This function calculates the nine ratios and determines which ones match
242 * a standard sample rate. If there's a match, then it is added to the list
243 * of supported sample rates.
244 *
245 * This function must be called by the machine driver's 'startup' function,
246 * otherwise the list of supported sample rates will not be available in
247 * time for ALSA.
248 *
249 * For setups with variable MCLKs, pass 0 as 'freq' argument. This will cause
250 * theoretically possible sample rates to be enabled. Call it again with a
251 * proper value set one the external clock is set (most probably you would do
252 * that from a machine's driver 'hw_param' hook.
253 */
cs4270_set_dai_sysclk(struct snd_soc_dai * codec_dai,int clk_id,unsigned int freq,int dir)254 static int cs4270_set_dai_sysclk(struct snd_soc_dai *codec_dai,
255 int clk_id, unsigned int freq, int dir)
256 {
257 struct snd_soc_codec *codec = codec_dai->codec;
258 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
259
260 cs4270->mclk = freq;
261 return 0;
262 }
263
264 /**
265 * cs4270_set_dai_fmt - configure the codec for the selected audio format
266 * @codec_dai: the codec DAI
267 * @format: a SND_SOC_DAIFMT_x value indicating the data format
268 *
269 * This function takes a bitmask of SND_SOC_DAIFMT_x bits and programs the
270 * codec accordingly.
271 *
272 * Currently, this function only supports SND_SOC_DAIFMT_I2S and
273 * SND_SOC_DAIFMT_LEFT_J. The CS4270 codec also supports right-justified
274 * data for playback only, but ASoC currently does not support different
275 * formats for playback vs. record.
276 */
cs4270_set_dai_fmt(struct snd_soc_dai * codec_dai,unsigned int format)277 static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
278 unsigned int format)
279 {
280 struct snd_soc_codec *codec = codec_dai->codec;
281 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
282
283 /* set DAI format */
284 switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
285 case SND_SOC_DAIFMT_I2S:
286 case SND_SOC_DAIFMT_LEFT_J:
287 cs4270->mode = format & SND_SOC_DAIFMT_FORMAT_MASK;
288 break;
289 default:
290 dev_err(codec->dev, "invalid dai format\n");
291 return -EINVAL;
292 }
293
294 /* set master/slave audio interface */
295 switch (format & SND_SOC_DAIFMT_MASTER_MASK) {
296 case SND_SOC_DAIFMT_CBS_CFS:
297 cs4270->slave_mode = 1;
298 break;
299 case SND_SOC_DAIFMT_CBM_CFM:
300 cs4270->slave_mode = 0;
301 break;
302 default:
303 /* all other modes are unsupported by the hardware */
304 dev_err(codec->dev, "Unknown master/slave configuration\n");
305 return -EINVAL;
306 }
307
308 return 0;
309 }
310
311 /**
312 * cs4270_hw_params - program the CS4270 with the given hardware parameters.
313 * @substream: the audio stream
314 * @params: the hardware parameters to set
315 * @dai: the SOC DAI (ignored)
316 *
317 * This function programs the hardware with the values provided.
318 * Specifically, the sample rate and the data format.
319 *
320 * The .ops functions are used to provide board-specific data, like input
321 * frequencies, to this driver. This function takes that information,
322 * combines it with the hardware parameters provided, and programs the
323 * hardware accordingly.
324 */
cs4270_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * dai)325 static int cs4270_hw_params(struct snd_pcm_substream *substream,
326 struct snd_pcm_hw_params *params,
327 struct snd_soc_dai *dai)
328 {
329 struct snd_soc_codec *codec = dai->codec;
330 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
331 int ret;
332 unsigned int i;
333 unsigned int rate;
334 unsigned int ratio;
335 int reg;
336
337 /* Figure out which MCLK/LRCK ratio to use */
338
339 rate = params_rate(params); /* Sampling rate, in Hz */
340 ratio = cs4270->mclk / rate; /* MCLK/LRCK ratio */
341
342 for (i = 0; i < NUM_MCLK_RATIOS; i++) {
343 if (cs4270_mode_ratios[i].ratio == ratio)
344 break;
345 }
346
347 if (i == NUM_MCLK_RATIOS) {
348 /* We did not find a matching ratio */
349 dev_err(codec->dev, "could not find matching ratio\n");
350 return -EINVAL;
351 }
352
353 /* Set the sample rate */
354
355 reg = snd_soc_read(codec, CS4270_MODE);
356 reg &= ~(CS4270_MODE_SPEED_MASK | CS4270_MODE_DIV_MASK);
357 reg |= cs4270_mode_ratios[i].mclk;
358
359 if (cs4270->slave_mode)
360 reg |= CS4270_MODE_SLAVE;
361 else
362 reg |= cs4270_mode_ratios[i].speed_mode;
363
364 ret = snd_soc_write(codec, CS4270_MODE, reg);
365 if (ret < 0) {
366 dev_err(codec->dev, "i2c write failed\n");
367 return ret;
368 }
369
370 /* Set the DAI format */
371
372 reg = snd_soc_read(codec, CS4270_FORMAT);
373 reg &= ~(CS4270_FORMAT_DAC_MASK | CS4270_FORMAT_ADC_MASK);
374
375 switch (cs4270->mode) {
376 case SND_SOC_DAIFMT_I2S:
377 reg |= CS4270_FORMAT_DAC_I2S | CS4270_FORMAT_ADC_I2S;
378 break;
379 case SND_SOC_DAIFMT_LEFT_J:
380 reg |= CS4270_FORMAT_DAC_LJ | CS4270_FORMAT_ADC_LJ;
381 break;
382 default:
383 dev_err(codec->dev, "unknown dai format\n");
384 return -EINVAL;
385 }
386
387 ret = snd_soc_write(codec, CS4270_FORMAT, reg);
388 if (ret < 0) {
389 dev_err(codec->dev, "i2c write failed\n");
390 return ret;
391 }
392
393 return ret;
394 }
395
396 /**
397 * cs4270_dai_mute - enable/disable the CS4270 external mute
398 * @dai: the SOC DAI
399 * @mute: 0 = disable mute, 1 = enable mute
400 *
401 * This function toggles the mute bits in the MUTE register. The CS4270's
402 * mute capability is intended for external muting circuitry, so if the
403 * board does not have the MUTEA or MUTEB pins connected to such circuitry,
404 * then this function will do nothing.
405 */
cs4270_dai_mute(struct snd_soc_dai * dai,int mute)406 static int cs4270_dai_mute(struct snd_soc_dai *dai, int mute)
407 {
408 struct snd_soc_codec *codec = dai->codec;
409 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
410 int reg6;
411
412 reg6 = snd_soc_read(codec, CS4270_MUTE);
413
414 if (mute)
415 reg6 |= CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B;
416 else {
417 reg6 &= ~(CS4270_MUTE_DAC_A | CS4270_MUTE_DAC_B);
418 reg6 |= cs4270->manual_mute;
419 }
420
421 return snd_soc_write(codec, CS4270_MUTE, reg6);
422 }
423
424 /**
425 * cs4270_soc_put_mute - put callback for the 'Master Playback switch'
426 * alsa control.
427 * @kcontrol: mixer control
428 * @ucontrol: control element information
429 *
430 * This function basically passes the arguments on to the generic
431 * snd_soc_put_volsw() function and saves the mute information in
432 * our private data structure. This is because we want to prevent
433 * cs4270_dai_mute() neglecting the user's decision to manually
434 * mute the codec's output.
435 *
436 * Returns 0 for success.
437 */
cs4270_soc_put_mute(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_value * ucontrol)438 static int cs4270_soc_put_mute(struct snd_kcontrol *kcontrol,
439 struct snd_ctl_elem_value *ucontrol)
440 {
441 struct snd_soc_codec *codec = snd_soc_kcontrol_codec(kcontrol);
442 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
443 int left = !ucontrol->value.integer.value[0];
444 int right = !ucontrol->value.integer.value[1];
445
446 cs4270->manual_mute = (left ? CS4270_MUTE_DAC_A : 0) |
447 (right ? CS4270_MUTE_DAC_B : 0);
448
449 return snd_soc_put_volsw(kcontrol, ucontrol);
450 }
451
452 /* A list of non-DAPM controls that the CS4270 supports */
453 static const struct snd_kcontrol_new cs4270_snd_controls[] = {
454 SOC_DOUBLE_R("Master Playback Volume",
455 CS4270_VOLA, CS4270_VOLB, 0, 0xFF, 1),
456 SOC_SINGLE("Digital Sidetone Switch", CS4270_FORMAT, 5, 1, 0),
457 SOC_SINGLE("Soft Ramp Switch", CS4270_TRANS, 6, 1, 0),
458 SOC_SINGLE("Zero Cross Switch", CS4270_TRANS, 5, 1, 0),
459 SOC_SINGLE("De-emphasis filter", CS4270_TRANS, 0, 1, 0),
460 SOC_SINGLE("Popguard Switch", CS4270_MODE, 0, 1, 1),
461 SOC_SINGLE("Auto-Mute Switch", CS4270_MUTE, 5, 1, 0),
462 SOC_DOUBLE("Master Capture Switch", CS4270_MUTE, 3, 4, 1, 1),
463 SOC_DOUBLE_EXT("Master Playback Switch", CS4270_MUTE, 0, 1, 1, 1,
464 snd_soc_get_volsw, cs4270_soc_put_mute),
465 };
466
467 static const struct snd_soc_dai_ops cs4270_dai_ops = {
468 .hw_params = cs4270_hw_params,
469 .set_sysclk = cs4270_set_dai_sysclk,
470 .set_fmt = cs4270_set_dai_fmt,
471 .digital_mute = cs4270_dai_mute,
472 };
473
474 static struct snd_soc_dai_driver cs4270_dai = {
475 .name = "cs4270-hifi",
476 .playback = {
477 .stream_name = "Playback",
478 .channels_min = 2,
479 .channels_max = 2,
480 .rates = SNDRV_PCM_RATE_CONTINUOUS,
481 .rate_min = 4000,
482 .rate_max = 216000,
483 .formats = CS4270_FORMATS,
484 },
485 .capture = {
486 .stream_name = "Capture",
487 .channels_min = 2,
488 .channels_max = 2,
489 .rates = SNDRV_PCM_RATE_CONTINUOUS,
490 .rate_min = 4000,
491 .rate_max = 216000,
492 .formats = CS4270_FORMATS,
493 },
494 .ops = &cs4270_dai_ops,
495 };
496
497 /**
498 * cs4270_probe - ASoC probe function
499 * @pdev: platform device
500 *
501 * This function is called when ASoC has all the pieces it needs to
502 * instantiate a sound driver.
503 */
cs4270_probe(struct snd_soc_codec * codec)504 static int cs4270_probe(struct snd_soc_codec *codec)
505 {
506 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
507 int ret;
508
509 /* Disable auto-mute. This feature appears to be buggy. In some
510 * situations, auto-mute will not deactivate when it should, so we want
511 * this feature disabled by default. An application (e.g. alsactl) can
512 * re-enabled it by using the controls.
513 */
514 ret = snd_soc_update_bits(codec, CS4270_MUTE, CS4270_MUTE_AUTO, 0);
515 if (ret < 0) {
516 dev_err(codec->dev, "i2c write failed\n");
517 return ret;
518 }
519
520 /* Disable automatic volume control. The hardware enables, and it
521 * causes volume change commands to be delayed, sometimes until after
522 * playback has started. An application (e.g. alsactl) can
523 * re-enabled it by using the controls.
524 */
525 ret = snd_soc_update_bits(codec, CS4270_TRANS,
526 CS4270_TRANS_SOFT | CS4270_TRANS_ZERO, 0);
527 if (ret < 0) {
528 dev_err(codec->dev, "i2c write failed\n");
529 return ret;
530 }
531
532 ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
533 cs4270->supplies);
534
535 return ret;
536 }
537
538 /**
539 * cs4270_remove - ASoC remove function
540 * @pdev: platform device
541 *
542 * This function is the counterpart to cs4270_probe().
543 */
cs4270_remove(struct snd_soc_codec * codec)544 static int cs4270_remove(struct snd_soc_codec *codec)
545 {
546 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
547
548 regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies), cs4270->supplies);
549
550 return 0;
551 };
552
553 #ifdef CONFIG_PM
554
555 /* This suspend/resume implementation can handle both - a simple standby
556 * where the codec remains powered, and a full suspend, where the voltage
557 * domain the codec is connected to is teared down and/or any other hardware
558 * reset condition is asserted.
559 *
560 * The codec's own power saving features are enabled in the suspend callback,
561 * and all registers are written back to the hardware when resuming.
562 */
563
cs4270_soc_suspend(struct snd_soc_codec * codec)564 static int cs4270_soc_suspend(struct snd_soc_codec *codec)
565 {
566 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
567 int reg, ret;
568
569 reg = snd_soc_read(codec, CS4270_PWRCTL) | CS4270_PWRCTL_PDN_ALL;
570 if (reg < 0)
571 return reg;
572
573 ret = snd_soc_write(codec, CS4270_PWRCTL, reg);
574 if (ret < 0)
575 return ret;
576
577 regulator_bulk_disable(ARRAY_SIZE(cs4270->supplies),
578 cs4270->supplies);
579
580 return 0;
581 }
582
cs4270_soc_resume(struct snd_soc_codec * codec)583 static int cs4270_soc_resume(struct snd_soc_codec *codec)
584 {
585 struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
586 int reg, ret;
587
588 ret = regulator_bulk_enable(ARRAY_SIZE(cs4270->supplies),
589 cs4270->supplies);
590 if (ret != 0)
591 return ret;
592
593 /* In case the device was put to hard reset during sleep, we need to
594 * wait 500ns here before any I2C communication. */
595 ndelay(500);
596
597 /* first restore the entire register cache ... */
598 regcache_sync(cs4270->regmap);
599
600 /* ... then disable the power-down bits */
601 reg = snd_soc_read(codec, CS4270_PWRCTL);
602 reg &= ~CS4270_PWRCTL_PDN_ALL;
603
604 return snd_soc_write(codec, CS4270_PWRCTL, reg);
605 }
606 #else
607 #define cs4270_soc_suspend NULL
608 #define cs4270_soc_resume NULL
609 #endif /* CONFIG_PM */
610
611 /*
612 * ASoC codec driver structure
613 */
614 static const struct snd_soc_codec_driver soc_codec_device_cs4270 = {
615 .probe = cs4270_probe,
616 .remove = cs4270_remove,
617 .suspend = cs4270_soc_suspend,
618 .resume = cs4270_soc_resume,
619
620 .controls = cs4270_snd_controls,
621 .num_controls = ARRAY_SIZE(cs4270_snd_controls),
622 .dapm_widgets = cs4270_dapm_widgets,
623 .num_dapm_widgets = ARRAY_SIZE(cs4270_dapm_widgets),
624 .dapm_routes = cs4270_dapm_routes,
625 .num_dapm_routes = ARRAY_SIZE(cs4270_dapm_routes),
626 };
627
628 /*
629 * cs4270_of_match - the device tree bindings
630 */
631 static const struct of_device_id cs4270_of_match[] = {
632 { .compatible = "cirrus,cs4270", },
633 { }
634 };
635 MODULE_DEVICE_TABLE(of, cs4270_of_match);
636
637 static const struct regmap_config cs4270_regmap = {
638 .reg_bits = 8,
639 .val_bits = 8,
640 .max_register = CS4270_LASTREG,
641 .reg_defaults = cs4270_reg_defaults,
642 .num_reg_defaults = ARRAY_SIZE(cs4270_reg_defaults),
643 .cache_type = REGCACHE_RBTREE,
644
645 .readable_reg = cs4270_reg_is_readable,
646 .volatile_reg = cs4270_reg_is_volatile,
647 };
648
649 /**
650 * cs4270_i2c_probe - initialize the I2C interface of the CS4270
651 * @i2c_client: the I2C client object
652 * @id: the I2C device ID (ignored)
653 *
654 * This function is called whenever the I2C subsystem finds a device that
655 * matches the device ID given via a prior call to i2c_add_driver().
656 */
cs4270_i2c_probe(struct i2c_client * i2c_client,const struct i2c_device_id * id)657 static int cs4270_i2c_probe(struct i2c_client *i2c_client,
658 const struct i2c_device_id *id)
659 {
660 struct device_node *np = i2c_client->dev.of_node;
661 struct cs4270_private *cs4270;
662 unsigned int val;
663 int ret, i;
664
665 cs4270 = devm_kzalloc(&i2c_client->dev, sizeof(struct cs4270_private),
666 GFP_KERNEL);
667 if (!cs4270)
668 return -ENOMEM;
669
670 /* get the power supply regulators */
671 for (i = 0; i < ARRAY_SIZE(supply_names); i++)
672 cs4270->supplies[i].supply = supply_names[i];
673
674 ret = devm_regulator_bulk_get(&i2c_client->dev,
675 ARRAY_SIZE(cs4270->supplies),
676 cs4270->supplies);
677 if (ret < 0)
678 return ret;
679
680 /* See if we have a way to bring the codec out of reset */
681 if (np) {
682 enum of_gpio_flags flags;
683 int gpio = of_get_named_gpio_flags(np, "reset-gpio", 0, &flags);
684
685 if (gpio_is_valid(gpio)) {
686 ret = devm_gpio_request_one(&i2c_client->dev, gpio,
687 flags & OF_GPIO_ACTIVE_LOW ?
688 GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH,
689 "cs4270 reset");
690 if (ret < 0)
691 return ret;
692 }
693 }
694
695 cs4270->regmap = devm_regmap_init_i2c(i2c_client, &cs4270_regmap);
696 if (IS_ERR(cs4270->regmap))
697 return PTR_ERR(cs4270->regmap);
698
699 /* Verify that we have a CS4270 */
700 ret = regmap_read(cs4270->regmap, CS4270_CHIPID, &val);
701 if (ret < 0) {
702 dev_err(&i2c_client->dev, "failed to read i2c at addr %X\n",
703 i2c_client->addr);
704 return ret;
705 }
706 /* The top four bits of the chip ID should be 1100. */
707 if ((val & 0xF0) != 0xC0) {
708 dev_err(&i2c_client->dev, "device at addr %X is not a CS4270\n",
709 i2c_client->addr);
710 return -ENODEV;
711 }
712
713 dev_info(&i2c_client->dev, "found device at i2c address %X\n",
714 i2c_client->addr);
715 dev_info(&i2c_client->dev, "hardware revision %X\n", val & 0xF);
716
717 i2c_set_clientdata(i2c_client, cs4270);
718
719 ret = snd_soc_register_codec(&i2c_client->dev,
720 &soc_codec_device_cs4270, &cs4270_dai, 1);
721 return ret;
722 }
723
724 /**
725 * cs4270_i2c_remove - remove an I2C device
726 * @i2c_client: the I2C client object
727 *
728 * This function is the counterpart to cs4270_i2c_probe().
729 */
cs4270_i2c_remove(struct i2c_client * i2c_client)730 static int cs4270_i2c_remove(struct i2c_client *i2c_client)
731 {
732 snd_soc_unregister_codec(&i2c_client->dev);
733 return 0;
734 }
735
736 /*
737 * cs4270_id - I2C device IDs supported by this driver
738 */
739 static const struct i2c_device_id cs4270_id[] = {
740 {"cs4270", 0},
741 {}
742 };
743 MODULE_DEVICE_TABLE(i2c, cs4270_id);
744
745 /*
746 * cs4270_i2c_driver - I2C device identification
747 *
748 * This structure tells the I2C subsystem how to identify and support a
749 * given I2C device type.
750 */
751 static struct i2c_driver cs4270_i2c_driver = {
752 .driver = {
753 .name = "cs4270",
754 .owner = THIS_MODULE,
755 .of_match_table = cs4270_of_match,
756 },
757 .id_table = cs4270_id,
758 .probe = cs4270_i2c_probe,
759 .remove = cs4270_i2c_remove,
760 };
761
762 module_i2c_driver(cs4270_i2c_driver);
763
764 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
765 MODULE_DESCRIPTION("Cirrus Logic CS4270 ALSA SoC Codec Driver");
766 MODULE_LICENSE("GPL");
767