sound/hda/hdac_regmap.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Regmap support for HD-audio verbs
  *
  * A virtual register is translated to one or more hda verbs for write,
  * vice versa for read.
  *
  * A few limitations:
  * - Provided for not all verbs but only subset standard non-volatile verbs.
  * - For reading, only AC_VERB_GET_* variants can be used.
  * - For writing, mapped to the *corresponding* AC_VERB_SET_* variants,
  *   so can't handle asymmetric verbs for read and write
  */

 #include <linux/slab.h>
 #include <linux/device.h>
 #include <linux/regmap.h>
 #include <linux/export.h>
 #include <linux/pm.h>
 #include <sound/core.h>
 #include <sound/hdaudio.h>
 #include <sound/hda_regmap.h>
 #include "local.h"

 static int codec_pm_lock(struct hdac_device *codec)
 {
 	return snd_hdac_keep_power_up(codec);
 }

 static void codec_pm_unlock(struct hdac_device *codec, int lock)
 {
 	if (lock == 1)
 		snd_hdac_power_down_pm(codec);
 }

 #define get_verb(reg)	(((reg) >> 8) & 0xfff)

 static bool hda_volatile_reg(struct device *dev, unsigned int reg)
 {
 	struct hdac_device *codec = dev_to_hdac_dev(dev);
 	unsigned int verb = get_verb(reg);

 	switch (verb) {
 	case AC_VERB_GET_PROC_COEF:
 		return !codec->cache_coef;
 	case AC_VERB_GET_COEF_INDEX:
 	case AC_VERB_GET_PROC_STATE:
 	case AC_VERB_GET_POWER_STATE:
 	case AC_VERB_GET_PIN_SENSE:
 	case AC_VERB_GET_HDMI_DIP_SIZE:
 	case AC_VERB_GET_HDMI_ELDD:
 	case AC_VERB_GET_HDMI_DIP_INDEX:
 	case AC_VERB_GET_HDMI_DIP_DATA:
 	case AC_VERB_GET_HDMI_DIP_XMIT:
 	case AC_VERB_GET_HDMI_CP_CTRL:
 	case AC_VERB_GET_HDMI_CHAN_SLOT:
 	case AC_VERB_GET_DEVICE_SEL:
 	case AC_VERB_GET_DEVICE_LIST:	/* read-only volatile */
 		return true;
 	}

 	return false;
 }

 static bool hda_writeable_reg(struct device *dev, unsigned int reg)
 {
 	struct hdac_device *codec = dev_to_hdac_dev(dev);
 	unsigned int verb = get_verb(reg);
 	const unsigned int *v;
 	int i;

 	snd_array_for_each(&codec->vendor_verbs, i, v) {
 		if (verb == *v)
 			return true;
 	}

 	if (codec->caps_overwriting)
 		return true;

 	switch (verb & 0xf00) {
 	case AC_VERB_GET_STREAM_FORMAT:
 	case AC_VERB_GET_AMP_GAIN_MUTE:
 		return true;
 	case AC_VERB_GET_PROC_COEF:
 		return codec->cache_coef;
 	case 0xf00:
 		break;
 	default:
 		return false;
 	}

 	switch (verb) {
 	case AC_VERB_GET_CONNECT_SEL:
 	case AC_VERB_GET_SDI_SELECT:
 	case AC_VERB_GET_PIN_WIDGET_CONTROL:
 	case AC_VERB_GET_UNSOLICITED_RESPONSE: /* only as SET_UNSOLICITED_ENABLE */
 	case AC_VERB_GET_BEEP_CONTROL:
 	case AC_VERB_GET_EAPD_BTLENABLE:
 	case AC_VERB_GET_DIGI_CONVERT_1:
 	case AC_VERB_GET_DIGI_CONVERT_2: /* only for beep control */
 	case AC_VERB_GET_VOLUME_KNOB_CONTROL:
 	case AC_VERB_GET_GPIO_MASK:
 	case AC_VERB_GET_GPIO_DIRECTION:
 	case AC_VERB_GET_GPIO_DATA: /* not for volatile read */
 	case AC_VERB_GET_GPIO_WAKE_MASK:
 	case AC_VERB_GET_GPIO_UNSOLICITED_RSP_MASK:
 	case AC_VERB_GET_GPIO_STICKY_MASK:
 		return true;
 	}

 	return false;
 }

 static bool hda_readable_reg(struct device *dev, unsigned int reg)
 {
 	struct hdac_device *codec = dev_to_hdac_dev(dev);
 	unsigned int verb = get_verb(reg);

 	if (codec->caps_overwriting)
 		return true;

 	switch (verb) {
 	case AC_VERB_PARAMETERS:
 	case AC_VERB_GET_CONNECT_LIST:
 	case AC_VERB_GET_SUBSYSTEM_ID:
 		return true;
 	/* below are basically writable, but disabled for reducing unnecessary
 	 * writes at sync
 	 */
 	case AC_VERB_GET_CONFIG_DEFAULT: /* usually just read */
 	case AC_VERB_GET_CONV: /* managed in PCM code */
 	case AC_VERB_GET_CVT_CHAN_COUNT: /* managed in HDMI CA code */
 		return true;
 	}

 	return hda_writeable_reg(dev, reg);
 }

 /*
  * Stereo amp pseudo register:
  * for making easier to handle the stereo volume control, we provide a
  * fake register to deal both left and right channels by a single
  * (pseudo) register access.  A verb consisting of SET_AMP_GAIN with
  * *both* SET_LEFT and SET_RIGHT bits takes a 16bit value, the lower 8bit
  * for the left and the upper 8bit for the right channel.
  */
 static bool is_stereo_amp_verb(unsigned int reg)
 {
 	if (((reg >> 8) & 0x700) != AC_VERB_SET_AMP_GAIN_MUTE)
 		return false;
 	return (reg & (AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT)) ==
 		(AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT);
 }

 /* read a pseudo stereo amp register (16bit left+right) */
 static int hda_reg_read_stereo_amp(struct hdac_device *codec,
 				   unsigned int reg, unsigned int *val)
 {
 	unsigned int left, right;
 	int err;

 	reg &= ~(AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT);
 	err = snd_hdac_exec_verb(codec, reg | AC_AMP_GET_LEFT, 0, &left);
 	if (err < 0)
 		return err;
 	err = snd_hdac_exec_verb(codec, reg | AC_AMP_GET_RIGHT, 0, &right);
 	if (err < 0)
 		return err;
 	*val = left | (right << 8);
 	return 0;
 }

 /* write a pseudo stereo amp register (16bit left+right) */
 static int hda_reg_write_stereo_amp(struct hdac_device *codec,
 				    unsigned int reg, unsigned int val)
 {
 	int err;
 	unsigned int verb, left, right;

 	verb = AC_VERB_SET_AMP_GAIN_MUTE << 8;
 	if (reg & AC_AMP_GET_OUTPUT)
 		verb |= AC_AMP_SET_OUTPUT;
 	else
 		verb |= AC_AMP_SET_INPUT | ((reg & 0xf) << 8);
 	reg = (reg & ~0xfffff) | verb;

 	left = val & 0xff;
 	right = (val >> 8) & 0xff;
 	if (left == right) {
 		reg |= AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT;
 		return snd_hdac_exec_verb(codec, reg | left, 0, NULL);
 	}

 	err = snd_hdac_exec_verb(codec, reg | AC_AMP_SET_LEFT | left, 0, NULL);
 	if (err < 0)
 		return err;
 	err = snd_hdac_exec_verb(codec, reg | AC_AMP_SET_RIGHT | right, 0, NULL);
 	if (err < 0)
 		return err;
 	return 0;
 }

 /* read a pseudo coef register (16bit) */
 static int hda_reg_read_coef(struct hdac_device *codec, unsigned int reg,
 			     unsigned int *val)
 {
 	unsigned int verb;
 	int err;

 	if (!codec->cache_coef)
 		return -EINVAL;
 	/* LSB 8bit = coef index */
 	verb = (reg & ~0xfff00) | (AC_VERB_SET_COEF_INDEX << 8);
 	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
 	if (err < 0)
 		return err;
 	verb = (reg & ~0xfffff) | (AC_VERB_GET_COEF_INDEX << 8);
 	return snd_hdac_exec_verb(codec, verb, 0, val);
 }

 /* write a pseudo coef register (16bit) */
 static int hda_reg_write_coef(struct hdac_device *codec, unsigned int reg,
 			      unsigned int val)
 {
 	unsigned int verb;
 	int err;

 	if (!codec->cache_coef)
 		return -EINVAL;
 	/* LSB 8bit = coef index */
 	verb = (reg & ~0xfff00) | (AC_VERB_SET_COEF_INDEX << 8);
 	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
 	if (err < 0)
 		return err;
 	verb = (reg & ~0xfffff) | (AC_VERB_GET_COEF_INDEX << 8) |
 		(val & 0xffff);
 	return snd_hdac_exec_verb(codec, verb, 0, NULL);
 }

 static int hda_reg_read(void *context, unsigned int reg, unsigned int *val)
 {
 	struct hdac_device *codec = context;
 	int verb = get_verb(reg);
 	int err;
 	int pm_lock = 0;

 	if (verb != AC_VERB_GET_POWER_STATE) {
 		pm_lock = codec_pm_lock(codec);
 		if (pm_lock < 0)
 			return -EAGAIN;
 	}
 	reg |= (codec->addr << 28);
 	if (is_stereo_amp_verb(reg)) {
 		err = hda_reg_read_stereo_amp(codec, reg, val);
 		goto out;
 	}
 	if (verb == AC_VERB_GET_PROC_COEF) {
 		err = hda_reg_read_coef(codec, reg, val);
 		goto out;
 	}
 	if ((verb & 0x700) == AC_VERB_SET_AMP_GAIN_MUTE)
 		reg &= ~AC_AMP_FAKE_MUTE;

 	err = snd_hdac_exec_verb(codec, reg, 0, val);
 	if (err < 0)
 		goto out;
 	/* special handling for asymmetric reads */
 	if (verb == AC_VERB_GET_POWER_STATE) {
 		if (*val & AC_PWRST_ERROR)
 			*val = -1;
 		else /* take only the actual state */
 			*val = (*val >> 4) & 0x0f;
 	}
  out:
 	codec_pm_unlock(codec, pm_lock);
 	return err;
 }

 static int hda_reg_write(void *context, unsigned int reg, unsigned int val)
 {
 	struct hdac_device *codec = context;
 	unsigned int verb;
 	int i, bytes, err;
 	int pm_lock = 0;

 	if (codec->caps_overwriting)
 		return 0;

 	reg &= ~0x00080000U; /* drop GET bit */
 	reg |= (codec->addr << 28);
 	verb = get_verb(reg);

 	if (verb != AC_VERB_SET_POWER_STATE) {
 		pm_lock = codec_pm_lock(codec);
 		if (pm_lock < 0)
 			return codec->lazy_cache ? 0 : -EAGAIN;
 	}

 	if (is_stereo_amp_verb(reg)) {
 		err = hda_reg_write_stereo_amp(codec, reg, val);
 		goto out;
 	}

 	if (verb == AC_VERB_SET_PROC_COEF) {
 		err = hda_reg_write_coef(codec, reg, val);
 		goto out;
 	}

 	switch (verb & 0xf00) {
 	case AC_VERB_SET_AMP_GAIN_MUTE:
 		if ((reg & AC_AMP_FAKE_MUTE) && (val & AC_AMP_MUTE))
 			val = 0;
 		verb = AC_VERB_SET_AMP_GAIN_MUTE;
 		if (reg & AC_AMP_GET_LEFT)
 			verb |= AC_AMP_SET_LEFT >> 8;
 		else
 			verb |= AC_AMP_SET_RIGHT >> 8;
 		if (reg & AC_AMP_GET_OUTPUT) {
 			verb |= AC_AMP_SET_OUTPUT >> 8;
 		} else {
 			verb |= AC_AMP_SET_INPUT >> 8;
 			verb |= reg & 0xf;
 		}
 		break;
 	}

 	switch (verb) {
 	case AC_VERB_SET_DIGI_CONVERT_1:
 		bytes = 2;
 		break;
 	case AC_VERB_SET_CONFIG_DEFAULT_BYTES_0:
 		bytes = 4;
 		break;
 	default:
 		bytes = 1;
 		break;
 	}

 	for (i = 0; i < bytes; i++) {
 		reg &= ~0xfffff;
 		reg |= (verb + i) << 8 | ((val >> (8 * i)) & 0xff);
 		err = snd_hdac_exec_verb(codec, reg, 0, NULL);
 		if (err < 0)
 			goto out;
 	}

  out:
 	codec_pm_unlock(codec, pm_lock);
 	return err;
 }

 static const struct regmap_config hda_regmap_cfg = {
 	.name = "hdaudio",
 	.reg_bits = 32,
 	.val_bits = 32,
 	.max_register = 0xfffffff,
 	.writeable_reg = hda_writeable_reg,
 	.readable_reg = hda_readable_reg,
 	.volatile_reg = hda_volatile_reg,
 	.cache_type = REGCACHE_MAPLE,
 	.reg_read = hda_reg_read,
 	.reg_write = hda_reg_write,
 	.use_single_read = true,
 	.use_single_write = true,
 	.disable_locking = true,
 };

 /**
  * snd_hdac_regmap_init - Initialize regmap for HDA register accesses
  * @codec: the codec object
  *
  * Returns zero for success or a negative error code.
  */
 int snd_hdac_regmap_init(struct hdac_device *codec)
 {
 	struct regmap *regmap;

 	regmap = regmap_init(&codec->dev, NULL, codec, &hda_regmap_cfg);
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);
 	codec->regmap = regmap;
 	snd_array_init(&codec->vendor_verbs, sizeof(unsigned int), 8);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(snd_hdac_regmap_init);

 /**
  * snd_hdac_regmap_exit - Release the regmap from HDA codec
  * @codec: the codec object
  */
 void snd_hdac_regmap_exit(struct hdac_device *codec)
 {
 	if (codec->regmap) {
 		regmap_exit(codec->regmap);
 		codec->regmap = NULL;
 		snd_array_free(&codec->vendor_verbs);
 	}
 }
 EXPORT_SYMBOL_GPL(snd_hdac_regmap_exit);

 /**
  * snd_hdac_regmap_add_vendor_verb - add a vendor-specific verb to regmap
  * @codec: the codec object
  * @verb: verb to allow accessing via regmap
  *
  * Returns zero for success or a negative error code.
  */
 int snd_hdac_regmap_add_vendor_verb(struct hdac_device *codec,
 				    unsigned int verb)
 {
 	unsigned int *p = snd_array_new(&codec->vendor_verbs);

 	if (!p)
 		return -ENOMEM;
 	*p = verb | 0x800; /* set GET bit */
 	return 0;
 }
 EXPORT_SYMBOL_GPL(snd_hdac_regmap_add_vendor_verb);

 /*
  * helper functions
  */

 /* write a pseudo-register value (w/o power sequence) */
 static int reg_raw_write(struct hdac_device *codec, unsigned int reg,
 			 unsigned int val)
 {
 	int err;

 	mutex_lock(&codec->regmap_lock);
 	if (!codec->regmap)
 		err = hda_reg_write(codec, reg, val);
 	else
 		err = regmap_write(codec->regmap, reg, val);
 	mutex_unlock(&codec->regmap_lock);
 	return err;
 }

 /* a helper macro to call @func_call; retry with power-up if failed */
 #define CALL_RAW_FUNC(codec, func_call)				\
 	({							\
 		int _err = func_call;				\
 		if (_err == -EAGAIN) {				\
 			_err = snd_hdac_power_up_pm(codec);	\
 			if (_err >= 0)				\
 				_err = func_call;		\
 			snd_hdac_power_down_pm(codec);		\
 		}						\
 		_err;})

 /**
  * snd_hdac_regmap_write_raw - write a pseudo register with power mgmt
  * @codec: the codec object
  * @reg: pseudo register
  * @val: value to write
  *
  * Returns zero if successful or a negative error code.
  */
 int snd_hdac_regmap_write_raw(struct hdac_device *codec, unsigned int reg,
 			      unsigned int val)
 {
 	return CALL_RAW_FUNC(codec, reg_raw_write(codec, reg, val));
 }
 EXPORT_SYMBOL_GPL(snd_hdac_regmap_write_raw);

 static int reg_raw_read(struct hdac_device *codec, unsigned int reg,
 			unsigned int *val, bool uncached)
 {
 	int err;

 	mutex_lock(&codec->regmap_lock);
 	if (uncached || !codec->regmap)
 		err = hda_reg_read(codec, reg, val);
 	else
 		err = regmap_read(codec->regmap, reg, val);
 	mutex_unlock(&codec->regmap_lock);
 	return err;
 }

 static int __snd_hdac_regmap_read_raw(struct hdac_device *codec,
 				      unsigned int reg, unsigned int *val,
 				      bool uncached)
 {
 	return CALL_RAW_FUNC(codec, reg_raw_read(codec, reg, val, uncached));
 }

 /**
  * snd_hdac_regmap_read_raw - read a pseudo register with power mgmt
  * @codec: the codec object
  * @reg: pseudo register
  * @val: pointer to store the read value
  *
  * Returns zero if successful or a negative error code.
  */
 int snd_hdac_regmap_read_raw(struct hdac_device *codec, unsigned int reg,
 			     unsigned int *val)
 {
 	return __snd_hdac_regmap_read_raw(codec, reg, val, false);
 }
 EXPORT_SYMBOL_GPL(snd_hdac_regmap_read_raw);

 /* Works like snd_hdac_regmap_read_raw(), but this doesn't read from the
  * cache but always via hda verbs.
  */
 int snd_hdac_regmap_read_raw_uncached(struct hdac_device *codec,
 				      unsigned int reg, unsigned int *val)
 {
 	return __snd_hdac_regmap_read_raw(codec, reg, val, true);
 }

 static int reg_raw_update(struct hdac_device *codec, unsigned int reg,
 			  unsigned int mask, unsigned int val)
 {
 	unsigned int orig;
 	bool change;
 	int err;

 	mutex_lock(&codec->regmap_lock);
 	if (codec->regmap) {
 		err = regmap_update_bits_check(codec->regmap, reg, mask, val,
 					       &change);
 		if (!err)
 			err = change ? 1 : 0;
 	} else {
 		err = hda_reg_read(codec, reg, &orig);
 		if (!err) {
 			val &= mask;
 			val |= orig & ~mask;
 			if (val != orig) {
 				err = hda_reg_write(codec, reg, val);
 				if (!err)
 					err = 1;
 			}
 		}
 	}
 	mutex_unlock(&codec->regmap_lock);
 	return err;
 }

 /**
  * snd_hdac_regmap_update_raw - update a pseudo register with power mgmt
  * @codec: the codec object
  * @reg: pseudo register
  * @mask: bit mask to update
  * @val: value to update
  *
  * Returns zero if successful or a negative error code.
  */
 int snd_hdac_regmap_update_raw(struct hdac_device *codec, unsigned int reg,
 			       unsigned int mask, unsigned int val)
 {
 	return CALL_RAW_FUNC(codec, reg_raw_update(codec, reg, mask, val));
 }
 EXPORT_SYMBOL_GPL(snd_hdac_regmap_update_raw);

 static int reg_raw_update_once(struct hdac_device *codec, unsigned int reg,
 			       unsigned int mask, unsigned int val)
 {
 	unsigned int orig;
 	int err;

 	if (!codec->regmap)
 		return reg_raw_update(codec, reg, mask, val);

 	mutex_lock(&codec->regmap_lock);
 	regcache_cache_only(codec->regmap, true);
 	err = regmap_read(codec->regmap, reg, &orig);
 	regcache_cache_only(codec->regmap, false);
 	if (err < 0)
 		err = regmap_update_bits(codec->regmap, reg, mask, val);
 	mutex_unlock(&codec->regmap_lock);
 	return err;
 }

 /**
  * snd_hdac_regmap_update_raw_once - initialize the register value only once
  * @codec: the codec object
  * @reg: pseudo register
  * @mask: bit mask to update
  * @val: value to update
  *
  * Performs the update of the register bits only once when the register
  * hasn't been initialized yet.  Used in HD-audio legacy driver.
  * Returns zero if successful or a negative error code
  */
 int snd_hdac_regmap_update_raw_once(struct hdac_device *codec, unsigned int reg,
 				    unsigned int mask, unsigned int val)
 {
 	return CALL_RAW_FUNC(codec, reg_raw_update_once(codec, reg, mask, val));
 }
 EXPORT_SYMBOL_GPL(snd_hdac_regmap_update_raw_once);

 /**
  * snd_hdac_regmap_sync - sync out the cached values for PM resume
  * @codec: the codec object
  */
 void snd_hdac_regmap_sync(struct hdac_device *codec)
 {
 	if (codec->regmap) {
 		mutex_lock(&codec->regmap_lock);
 		regcache_sync(codec->regmap);
 		mutex_unlock(&codec->regmap_lock);
 	}
 }
 EXPORT_SYMBOL_GPL(snd_hdac_regmap_sync);
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Regmap support for HD-audio verbs
	*
	* A virtual register is translated to one or more hda verbs for write,
	* vice versa for read.
	*
	* A few limitations:
	* - Provided for not all verbs but only subset standard non-volatile verbs.
	* - For reading, only AC_VERB_GET_* variants can be used.
	* - For writing, mapped to the corresponding AC_VERB_SET_* variants,
	* so can't handle asymmetric verbs for read and write
	*/

	#include <linux/slab.h>
	#include <linux/device.h>
	#include <linux/regmap.h>
	#include <linux/export.h>
	#include <linux/pm.h>
	#include <sound/core.h>
	#include <sound/hdaudio.h>
	#include <sound/hda_regmap.h>
	#include "local.h"

	static int codec_pm_lock(struct hdac_device *codec)
	{
	return snd_hdac_keep_power_up(codec);
	}

	static void codec_pm_unlock(struct hdac_device *codec, int lock)
	{
	if (lock == 1)
	snd_hdac_power_down_pm(codec);
	}

	#define get_verb(reg) (((reg) >> 8) & 0xfff)

	static bool hda_volatile_reg(struct device *dev, unsigned int reg)
	{
	struct hdac_device *codec = dev_to_hdac_dev(dev);
	unsigned int verb = get_verb(reg);

	switch (verb) {
	case AC_VERB_GET_PROC_COEF:
	return !codec->cache_coef;
	case AC_VERB_GET_COEF_INDEX:
	case AC_VERB_GET_PROC_STATE:
	case AC_VERB_GET_POWER_STATE:
	case AC_VERB_GET_PIN_SENSE:
	case AC_VERB_GET_HDMI_DIP_SIZE:
	case AC_VERB_GET_HDMI_ELDD:
	case AC_VERB_GET_HDMI_DIP_INDEX:
	case AC_VERB_GET_HDMI_DIP_DATA:
	case AC_VERB_GET_HDMI_DIP_XMIT:
	case AC_VERB_GET_HDMI_CP_CTRL:
	case AC_VERB_GET_HDMI_CHAN_SLOT:
	case AC_VERB_GET_DEVICE_SEL:
	case AC_VERB_GET_DEVICE_LIST: /* read-only volatile */
	return true;
	}

	return false;
	}

	static bool hda_writeable_reg(struct device *dev, unsigned int reg)
	{
	struct hdac_device *codec = dev_to_hdac_dev(dev);
	unsigned int verb = get_verb(reg);
	const unsigned int *v;
	int i;

	snd_array_for_each(&codec->vendor_verbs, i, v) {
	if (verb == *v)
	return true;
	}

	if (codec->caps_overwriting)
	return true;

	switch (verb & 0xf00) {
	case AC_VERB_GET_STREAM_FORMAT:
	case AC_VERB_GET_AMP_GAIN_MUTE:
	return true;
	case AC_VERB_GET_PROC_COEF:
	return codec->cache_coef;
	case 0xf00:
	break;
	default:
	return false;
	}

	switch (verb) {
	case AC_VERB_GET_CONNECT_SEL:
	case AC_VERB_GET_SDI_SELECT:
	case AC_VERB_GET_PIN_WIDGET_CONTROL:
	case AC_VERB_GET_UNSOLICITED_RESPONSE: /* only as SET_UNSOLICITED_ENABLE */
	case AC_VERB_GET_BEEP_CONTROL:
	case AC_VERB_GET_EAPD_BTLENABLE:
	case AC_VERB_GET_DIGI_CONVERT_1:
	case AC_VERB_GET_DIGI_CONVERT_2: /* only for beep control */
	case AC_VERB_GET_VOLUME_KNOB_CONTROL:
	case AC_VERB_GET_GPIO_MASK:
	case AC_VERB_GET_GPIO_DIRECTION:
	case AC_VERB_GET_GPIO_DATA: /* not for volatile read */
	case AC_VERB_GET_GPIO_WAKE_MASK:
	case AC_VERB_GET_GPIO_UNSOLICITED_RSP_MASK:
	case AC_VERB_GET_GPIO_STICKY_MASK:
	return true;
	}

	return false;
	}

	static bool hda_readable_reg(struct device *dev, unsigned int reg)
	{
	struct hdac_device *codec = dev_to_hdac_dev(dev);
	unsigned int verb = get_verb(reg);

	if (codec->caps_overwriting)
	return true;

	switch (verb) {
	case AC_VERB_PARAMETERS:
	case AC_VERB_GET_CONNECT_LIST:
	case AC_VERB_GET_SUBSYSTEM_ID:
	return true;
	/* below are basically writable, but disabled for reducing unnecessary
	* writes at sync
	*/
	case AC_VERB_GET_CONFIG_DEFAULT: /* usually just read */
	case AC_VERB_GET_CONV: /* managed in PCM code */
	case AC_VERB_GET_CVT_CHAN_COUNT: /* managed in HDMI CA code */
	return true;
	}

	return hda_writeable_reg(dev, reg);
	}

	/*
	* Stereo amp pseudo register:
	* for making easier to handle the stereo volume control, we provide a
	* fake register to deal both left and right channels by a single
	* (pseudo) register access. A verb consisting of SET_AMP_GAIN with
	* both SET_LEFT and SET_RIGHT bits takes a 16bit value, the lower 8bit
	* for the left and the upper 8bit for the right channel.
	*/
	static bool is_stereo_amp_verb(unsigned int reg)
	{
	if (((reg >> 8) & 0x700) != AC_VERB_SET_AMP_GAIN_MUTE)
	return false;
	return (reg & (AC_AMP_SET_LEFT \| AC_AMP_SET_RIGHT)) ==
	(AC_AMP_SET_LEFT \| AC_AMP_SET_RIGHT);
	}

	/* read a pseudo stereo amp register (16bit left+right) */
	static int hda_reg_read_stereo_amp(struct hdac_device *codec,
	unsigned int reg, unsigned int *val)
	{
	unsigned int left, right;
	int err;

	reg &= ~(AC_AMP_SET_LEFT \| AC_AMP_SET_RIGHT);
	err = snd_hdac_exec_verb(codec, reg \| AC_AMP_GET_LEFT, 0, &left);
	if (err < 0)
	return err;
	err = snd_hdac_exec_verb(codec, reg \| AC_AMP_GET_RIGHT, 0, &right);
	if (err < 0)
	return err;
	*val = left \| (right << 8);
	return 0;
	}

	/* write a pseudo stereo amp register (16bit left+right) */
	static int hda_reg_write_stereo_amp(struct hdac_device *codec,
	unsigned int reg, unsigned int val)
	{
	int err;
	unsigned int verb, left, right;

	verb = AC_VERB_SET_AMP_GAIN_MUTE << 8;
	if (reg & AC_AMP_GET_OUTPUT)
	verb \|= AC_AMP_SET_OUTPUT;
	else
	verb \|= AC_AMP_SET_INPUT \| ((reg & 0xf) << 8);
	reg = (reg & ~0xfffff) \| verb;

	left = val & 0xff;
	right = (val >> 8) & 0xff;
	if (left == right) {
	reg \|= AC_AMP_SET_LEFT \| AC_AMP_SET_RIGHT;
	return snd_hdac_exec_verb(codec, reg \| left, 0, NULL);
	}

	err = snd_hdac_exec_verb(codec, reg \| AC_AMP_SET_LEFT \| left, 0, NULL);
	if (err < 0)
	return err;
	err = snd_hdac_exec_verb(codec, reg \| AC_AMP_SET_RIGHT \| right, 0, NULL);
	if (err < 0)
	return err;
	return 0;
	}

	/* read a pseudo coef register (16bit) */
	static int hda_reg_read_coef(struct hdac_device *codec, unsigned int reg,
	unsigned int *val)
	{
	unsigned int verb;
	int err;

	if (!codec->cache_coef)
	return -EINVAL;
	/* LSB 8bit = coef index */
	verb = (reg & ~0xfff00) \| (AC_VERB_SET_COEF_INDEX << 8);
	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
	if (err < 0)
	return err;
	verb = (reg & ~0xfffff) \| (AC_VERB_GET_COEF_INDEX << 8);
	return snd_hdac_exec_verb(codec, verb, 0, val);
	}

	/* write a pseudo coef register (16bit) */
	static int hda_reg_write_coef(struct hdac_device *codec, unsigned int reg,
	unsigned int val)
	{
	unsigned int verb;
	int err;

	if (!codec->cache_coef)
	return -EINVAL;
	/* LSB 8bit = coef index */
	verb = (reg & ~0xfff00) \| (AC_VERB_SET_COEF_INDEX << 8);
	err = snd_hdac_exec_verb(codec, verb, 0, NULL);
	if (err < 0)
	return err;
	verb = (reg & ~0xfffff) \| (AC_VERB_GET_COEF_INDEX << 8) \|
	(val & 0xffff);
	return snd_hdac_exec_verb(codec, verb, 0, NULL);
	}

	static int hda_reg_read(void context, unsigned int reg, unsigned int val)
	{
	struct hdac_device *codec = context;
	int verb = get_verb(reg);
	int err;
	int pm_lock = 0;

	if (verb != AC_VERB_GET_POWER_STATE) {
	pm_lock = codec_pm_lock(codec);
	if (pm_lock < 0)
	return -EAGAIN;
	}
	reg \|= (codec->addr << 28);
	if (is_stereo_amp_verb(reg)) {
	err = hda_reg_read_stereo_amp(codec, reg, val);
	goto out;
	}
	if (verb == AC_VERB_GET_PROC_COEF) {
	err = hda_reg_read_coef(codec, reg, val);
	goto out;
	}
	if ((verb & 0x700) == AC_VERB_SET_AMP_GAIN_MUTE)
	reg &= ~AC_AMP_FAKE_MUTE;

	err = snd_hdac_exec_verb(codec, reg, 0, val);
	if (err < 0)
	goto out;
	/* special handling for asymmetric reads */
	if (verb == AC_VERB_GET_POWER_STATE) {
	if (*val & AC_PWRST_ERROR)
	*val = -1;
	else /* take only the actual state */
	val = (val >> 4) & 0x0f;
	}
	out:
	codec_pm_unlock(codec, pm_lock);
	return err;
	}

	static int hda_reg_write(void *context, unsigned int reg, unsigned int val)
	{
	struct hdac_device *codec = context;
	unsigned int verb;
	int i, bytes, err;
	int pm_lock = 0;

	if (codec->caps_overwriting)
	return 0;

	reg &= ~0x00080000U; /* drop GET bit */
	reg \|= (codec->addr << 28);
	verb = get_verb(reg);

	if (verb != AC_VERB_SET_POWER_STATE) {
	pm_lock = codec_pm_lock(codec);
	if (pm_lock < 0)
	return codec->lazy_cache ? 0 : -EAGAIN;
	}

	if (is_stereo_amp_verb(reg)) {
	err = hda_reg_write_stereo_amp(codec, reg, val);
	goto out;
	}

	if (verb == AC_VERB_SET_PROC_COEF) {
	err = hda_reg_write_coef(codec, reg, val);
	goto out;
	}

	switch (verb & 0xf00) {
	case AC_VERB_SET_AMP_GAIN_MUTE:
	if ((reg & AC_AMP_FAKE_MUTE) && (val & AC_AMP_MUTE))
	val = 0;
	verb = AC_VERB_SET_AMP_GAIN_MUTE;
	if (reg & AC_AMP_GET_LEFT)
	verb \|= AC_AMP_SET_LEFT >> 8;
	else
	verb \|= AC_AMP_SET_RIGHT >> 8;
	if (reg & AC_AMP_GET_OUTPUT) {
	verb \|= AC_AMP_SET_OUTPUT >> 8;
	} else {
	verb \|= AC_AMP_SET_INPUT >> 8;
	verb \|= reg & 0xf;
	}
	break;
	}

	switch (verb) {
	case AC_VERB_SET_DIGI_CONVERT_1:
	bytes = 2;
	break;
	case AC_VERB_SET_CONFIG_DEFAULT_BYTES_0:
	bytes = 4;
	break;
	default:
	bytes = 1;
	break;
	}

	for (i = 0; i < bytes; i++) {
	reg &= ~0xfffff;
	reg \|= (verb + i) << 8 \| ((val >> (8 * i)) & 0xff);
	err = snd_hdac_exec_verb(codec, reg, 0, NULL);
	if (err < 0)
	goto out;
	}

	out:
	codec_pm_unlock(codec, pm_lock);
	return err;
	}

	static const struct regmap_config hda_regmap_cfg = {
	.name = "hdaudio",
	.reg_bits = 32,
	.val_bits = 32,
	.max_register = 0xfffffff,
	.writeable_reg = hda_writeable_reg,
	.readable_reg = hda_readable_reg,
	.volatile_reg = hda_volatile_reg,
	.cache_type = REGCACHE_MAPLE,
	.reg_read = hda_reg_read,
	.reg_write = hda_reg_write,
	.use_single_read = true,
	.use_single_write = true,
	.disable_locking = true,
	};

	/**
	* snd_hdac_regmap_init - Initialize regmap for HDA register accesses
	* @codec: the codec object
	*
	* Returns zero for success or a negative error code.
	*/
	int snd_hdac_regmap_init(struct hdac_device *codec)
	{
	struct regmap *regmap;

	regmap = regmap_init(&codec->dev, NULL, codec, &hda_regmap_cfg);
	if (IS_ERR(regmap))
	return PTR_ERR(regmap);
	codec->regmap = regmap;
	snd_array_init(&codec->vendor_verbs, sizeof(unsigned int), 8);
	return 0;
	}
	EXPORT_SYMBOL_GPL(snd_hdac_regmap_init);

	/**
	* snd_hdac_regmap_exit - Release the regmap from HDA codec
	* @codec: the codec object
	*/
	void snd_hdac_regmap_exit(struct hdac_device *codec)
	{
	if (codec->regmap) {
	regmap_exit(codec->regmap);
	codec->regmap = NULL;
	snd_array_free(&codec->vendor_verbs);
	}
	}
	EXPORT_SYMBOL_GPL(snd_hdac_regmap_exit);

	/**
	* snd_hdac_regmap_add_vendor_verb - add a vendor-specific verb to regmap
	* @codec: the codec object
	* @verb: verb to allow accessing via regmap
	*
	* Returns zero for success or a negative error code.
	*/
	int snd_hdac_regmap_add_vendor_verb(struct hdac_device *codec,
	unsigned int verb)
	{
	unsigned int *p = snd_array_new(&codec->vendor_verbs);

	if (!p)
	return -ENOMEM;
	p = verb \| 0x800; / set GET bit */
	return 0;
	}
	EXPORT_SYMBOL_GPL(snd_hdac_regmap_add_vendor_verb);

	/*
	* helper functions
	*/

	/* write a pseudo-register value (w/o power sequence) */
	static int reg_raw_write(struct hdac_device *codec, unsigned int reg,
	unsigned int val)
	{
	int err;

	mutex_lock(&codec->regmap_lock);
	if (!codec->regmap)
	err = hda_reg_write(codec, reg, val);
	else
	err = regmap_write(codec->regmap, reg, val);
	mutex_unlock(&codec->regmap_lock);
	return err;
	}

	/* a helper macro to call @func_call; retry with power-up if failed */
	#define CALL_RAW_FUNC(codec, func_call) \
	({ \
	int _err = func_call; \
	if (_err == -EAGAIN) { \
	_err = snd_hdac_power_up_pm(codec); \
	if (_err >= 0) \
	_err = func_call; \
	snd_hdac_power_down_pm(codec); \
	} \
	_err;})

	/**
	* snd_hdac_regmap_write_raw - write a pseudo register with power mgmt
	* @codec: the codec object
	* @reg: pseudo register
	* @val: value to write
	*
	* Returns zero if successful or a negative error code.
	*/
	int snd_hdac_regmap_write_raw(struct hdac_device *codec, unsigned int reg,
	unsigned int val)
	{
	return CALL_RAW_FUNC(codec, reg_raw_write(codec, reg, val));
	}
	EXPORT_SYMBOL_GPL(snd_hdac_regmap_write_raw);

	static int reg_raw_read(struct hdac_device *codec, unsigned int reg,
	unsigned int *val, bool uncached)
	{
	int err;

	mutex_lock(&codec->regmap_lock);
	if (uncached \|\| !codec->regmap)
	err = hda_reg_read(codec, reg, val);
	else
	err = regmap_read(codec->regmap, reg, val);
	mutex_unlock(&codec->regmap_lock);
	return err;
	}

	static int __snd_hdac_regmap_read_raw(struct hdac_device *codec,
	unsigned int reg, unsigned int *val,
	bool uncached)
	{
	return CALL_RAW_FUNC(codec, reg_raw_read(codec, reg, val, uncached));
	}

	/**
	* snd_hdac_regmap_read_raw - read a pseudo register with power mgmt
	* @codec: the codec object
	* @reg: pseudo register
	* @val: pointer to store the read value
	*
	* Returns zero if successful or a negative error code.
	*/
	int snd_hdac_regmap_read_raw(struct hdac_device *codec, unsigned int reg,
	unsigned int *val)
	{
	return __snd_hdac_regmap_read_raw(codec, reg, val, false);
	}
	EXPORT_SYMBOL_GPL(snd_hdac_regmap_read_raw);

	/* Works like snd_hdac_regmap_read_raw(), but this doesn't read from the
	* cache but always via hda verbs.
	*/
	int snd_hdac_regmap_read_raw_uncached(struct hdac_device *codec,
	unsigned int reg, unsigned int *val)
	{
	return __snd_hdac_regmap_read_raw(codec, reg, val, true);
	}

	static int reg_raw_update(struct hdac_device *codec, unsigned int reg,
	unsigned int mask, unsigned int val)
	{
	unsigned int orig;
	bool change;
	int err;

	mutex_lock(&codec->regmap_lock);
	if (codec->regmap) {
	err = regmap_update_bits_check(codec->regmap, reg, mask, val,
	&change);
	if (!err)
	err = change ? 1 : 0;
	} else {
	err = hda_reg_read(codec, reg, &orig);
	if (!err) {
	val &= mask;
	val \|= orig & ~mask;
	if (val != orig) {
	err = hda_reg_write(codec, reg, val);
	if (!err)
	err = 1;
	}
	}
	}
	mutex_unlock(&codec->regmap_lock);
	return err;
	}

	/**
	* snd_hdac_regmap_update_raw - update a pseudo register with power mgmt
	* @codec: the codec object
	* @reg: pseudo register
	* @mask: bit mask to update
	* @val: value to update
	*
	* Returns zero if successful or a negative error code.
	*/
	int snd_hdac_regmap_update_raw(struct hdac_device *codec, unsigned int reg,
	unsigned int mask, unsigned int val)
	{
	return CALL_RAW_FUNC(codec, reg_raw_update(codec, reg, mask, val));
	}
	EXPORT_SYMBOL_GPL(snd_hdac_regmap_update_raw);

	static int reg_raw_update_once(struct hdac_device *codec, unsigned int reg,
	unsigned int mask, unsigned int val)
	{
	unsigned int orig;
	int err;

	if (!codec->regmap)
	return reg_raw_update(codec, reg, mask, val);

	mutex_lock(&codec->regmap_lock);
	regcache_cache_only(codec->regmap, true);
	err = regmap_read(codec->regmap, reg, &orig);
	regcache_cache_only(codec->regmap, false);
	if (err < 0)
	err = regmap_update_bits(codec->regmap, reg, mask, val);
	mutex_unlock(&codec->regmap_lock);
	return err;
	}

	/**
	* snd_hdac_regmap_update_raw_once - initialize the register value only once
	* @codec: the codec object
	* @reg: pseudo register
	* @mask: bit mask to update
	* @val: value to update
	*
	* Performs the update of the register bits only once when the register
	* hasn't been initialized yet. Used in HD-audio legacy driver.
	* Returns zero if successful or a negative error code
	*/
	int snd_hdac_regmap_update_raw_once(struct hdac_device *codec, unsigned int reg,
	unsigned int mask, unsigned int val)
	{
	return CALL_RAW_FUNC(codec, reg_raw_update_once(codec, reg, mask, val));
	}
	EXPORT_SYMBOL_GPL(snd_hdac_regmap_update_raw_once);

	/**
	* snd_hdac_regmap_sync - sync out the cached values for PM resume
	* @codec: the codec object
	*/
	void snd_hdac_regmap_sync(struct hdac_device *codec)
	{
	if (codec->regmap) {
	mutex_lock(&codec->regmap_lock);
	regcache_sync(codec->regmap);
	mutex_unlock(&codec->regmap_lock);
	}
	}
	EXPORT_SYMBOL_GPL(snd_hdac_regmap_sync);