Patchwork [1/3] mfd: max8997: use regmap to access registers

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Submitter Robert Baldyga
Date March 11, 2014, 1:58 p.m.
Message ID <1394546304-15191-2-git-send-email-r.baldyga@samsung.com>
Download mbox | patch
Permalink /patch/329115/
State New
Headers show

Comments

Robert Baldyga - March 11, 2014, 1:58 p.m.
This patch modifies max8997 driver and each associated function driver,
to use regmap instead of operating directly on i2c bus. It will allow to
simplify IRQ handling using regmap-irq.

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
---
 drivers/extcon/extcon-max8997.c     |   31 ++++----
 drivers/input/misc/max8997_haptic.c |   34 +++++----
 drivers/leds/leds-max8997.c         |   13 ++--
 drivers/mfd/max8997-irq.c           |   64 ++++++----------
 drivers/mfd/max8997.c               |  143 ++++++++++++++++-------------------
 drivers/power/max8997_charger.c     |   33 ++++----
 drivers/regulator/max8997.c         |   87 ++++++++++-----------
 drivers/rtc/rtc-max8997.c           |   56 ++++++++------
 include/linux/mfd/max8997-private.h |   17 ++---
 9 files changed, 229 insertions(+), 249 deletions(-)
Krzysztof Kozlowski - March 11, 2014, 2:32 p.m.
On Tue, 2014-03-11 at 14:58 +0100, Robert Baldyga wrote:
> This patch modifies max8997 driver and each associated function driver,
> to use regmap instead of operating directly on i2c bus. It will allow to
> simplify IRQ handling using regmap-irq.
> 
> Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
> ---
>  drivers/extcon/extcon-max8997.c     |   31 ++++----
>  drivers/input/misc/max8997_haptic.c |   34 +++++----
>  drivers/leds/leds-max8997.c         |   13 ++--
>  drivers/mfd/max8997-irq.c           |   64 ++++++----------
>  drivers/mfd/max8997.c               |  143 ++++++++++++++++-------------------
>  drivers/power/max8997_charger.c     |   33 ++++----
>  drivers/regulator/max8997.c         |   87 ++++++++++-----------
>  drivers/rtc/rtc-max8997.c           |   56 ++++++++------
>  include/linux/mfd/max8997-private.h |   17 ++---
>  9 files changed, 229 insertions(+), 249 deletions(-)

I think you should also add "select REGMAP_I2C" to the main driver
config secion (drivers/mfd/Kconfig).


(...)

> diff --git a/drivers/mfd/max8997-irq.c b/drivers/mfd/max8997-irq.c
> index 43fa614..656d03b 100644
> --- a/drivers/mfd/max8997-irq.c
> +++ b/drivers/mfd/max8997-irq.c
> @@ -26,6 +26,7 @@
>  #include <linux/interrupt.h>
>  #include <linux/mfd/max8997.h>
>  #include <linux/mfd/max8997-private.h>
> +#include <linux/regmap.h>
>  
>  static const u8 max8997_mask_reg[] = {
>  	[PMIC_INT1] = MAX8997_REG_INT1MSK,
> @@ -41,25 +42,6 @@ static const u8 max8997_mask_reg[] = {
>  	[FLASH_STATUS] = MAX8997_REG_INVALID,
>  };
>  
> -static struct i2c_client *get_i2c(struct max8997_dev *max8997,
> -				enum max8997_irq_source src)
> -{
> -	switch (src) {
> -	case PMIC_INT1 ... PMIC_INT4:
> -		return max8997->i2c;
> -	case FUEL_GAUGE:
> -		return NULL;
> -	case MUIC_INT1 ... MUIC_INT3:
> -		return max8997->muic;
> -	case GPIO_LOW ... GPIO_HI:
> -		return max8997->i2c;
> -	case FLASH_STATUS:
> -		return max8997->i2c;
> -	default:
> -		return ERR_PTR(-EINVAL);
> -	}
> -}
> -
>  struct max8997_irq_data {
>  	int mask;
>  	enum max8997_irq_source group;
> @@ -124,15 +106,20 @@ static void max8997_irq_sync_unlock(struct irq_data *data)
>  	int i;
>  
>  	for (i = 0; i < MAX8997_IRQ_GROUP_NR; i++) {
> +		struct regmap *map;
>  		u8 mask_reg = max8997_mask_reg[i];
> -		struct i2c_client *i2c = get_i2c(max8997, i);
> +
> +		if (i >= MUIC_INT1 && i <= MUIC_INT3)
> +			map = max8997->regmap_muic;
> +		else
> +			map = max8997->regmap;
>  
>  		if (mask_reg == MAX8997_REG_INVALID ||
> -				IS_ERR_OR_NULL(i2c))
> +				IS_ERR_OR_NULL(map))
>  			continue;
>  		max8997->irq_masks_cache[i] = max8997->irq_masks_cur[i];
>  
> -		max8997_write_reg(i2c, max8997_mask_reg[i],
> +		regmap_write(map, max8997_mask_reg[i],
>  				max8997->irq_masks_cur[i]);
>  	}
>  
> @@ -180,12 +167,12 @@ static struct irq_chip max8997_irq_chip = {
>  static irqreturn_t max8997_irq_thread(int irq, void *data)
>  {
>  	struct max8997_dev *max8997 = data;
> -	u8 irq_reg[MAX8997_IRQ_GROUP_NR] = {};
> -	u8 irq_src;
> +	unsigned int irq_reg[MAX8997_IRQ_GROUP_NR] = {};
> +	unsigned int irq_src;
>  	int ret;
>  	int i, cur_irq;
>  
> -	ret = max8997_read_reg(max8997->i2c, MAX8997_REG_INTSRC, &irq_src);
> +	ret = regmap_read(max8997->regmap, MAX8997_REG_INTSRC, &irq_src);
>  	if (ret < 0) {
>  		dev_err(max8997->dev, "Failed to read interrupt source: %d\n",
>  				ret);
> @@ -194,8 +181,9 @@ static irqreturn_t max8997_irq_thread(int irq, void *data)
>  
>  	if (irq_src & MAX8997_IRQSRC_PMIC) {
>  		/* PMIC INT1 ~ INT4 */
> -		max8997_bulk_read(max8997->i2c, MAX8997_REG_INT1, 4,
> -				&irq_reg[PMIC_INT1]);
> +		for (i = 0; i < 4; ++i)
> +			regmap_read(max8997->regmap,
> +				MAX8997_REG_INT1+i, &irq_reg[PMIC_INT1+i]);

Can't you use here one bulk read instead of 4xregmap_read()?


>  	}
>  	if (irq_src & MAX8997_IRQSRC_FUELGAUGE) {
>  		/*
> @@ -215,8 +203,9 @@ static irqreturn_t max8997_irq_thread(int irq, void *data)
>  	}
>  	if (irq_src & MAX8997_IRQSRC_MUIC) {
>  		/* MUIC INT1 ~ INT3 */
> -		max8997_bulk_read(max8997->muic, MAX8997_MUIC_REG_INT1, 3,
> -				&irq_reg[MUIC_INT1]);
> +		for (i = 0; i < 3; ++i)
> +			regmap_read(max8997->regmap_muic,
> +				MAX8997_MUIC_REG_INT1+i, &irq_reg[MUIC_INT1+i]);

Same as above - bulk.

>  	}
>  	if (irq_src & MAX8997_IRQSRC_GPIO) {
>  		/* GPIO Interrupt */
> @@ -225,8 +214,8 @@ static irqreturn_t max8997_irq_thread(int irq, void *data)
>  		irq_reg[GPIO_LOW] = 0;
>  		irq_reg[GPIO_HI] = 0;
>  
> -		max8997_bulk_read(max8997->i2c, MAX8997_REG_GPIOCNTL1,
> -				MAX8997_NUM_GPIO, gpio_info);
> +		regmap_bulk_read(max8997->regmap, MAX8997_REG_GPIOCNTL1,
> +				gpio_info, MAX8997_NUM_GPIO);
>  		for (i = 0; i < MAX8997_NUM_GPIO; i++) {
>  			bool interrupt = false;
>  
> @@ -260,7 +249,7 @@ static irqreturn_t max8997_irq_thread(int irq, void *data)
>  	}
>  	if (irq_src & MAX8997_IRQSRC_FLASH) {
>  		/* Flash Status Interrupt */
> -		ret = max8997_read_reg(max8997->i2c, MAX8997_REG_FLASHSTATUS,
> +		ret = regmap_read(max8997->regmap, MAX8997_REG_FLASHSTATUS,
>  				&irq_reg[FLASH_STATUS]);
>  	}
>  
> @@ -312,7 +301,7 @@ int max8997_irq_init(struct max8997_dev *max8997)
>  	struct irq_domain *domain;
>  	int i;
>  	int ret;
> -	u8 val;
> +	unsigned int val;
>  
>  	if (!max8997->irq) {
>  		dev_warn(max8997->dev, "No interrupt specified.\n");
> @@ -323,22 +312,19 @@ int max8997_irq_init(struct max8997_dev *max8997)
>  
>  	/* Mask individual interrupt sources */
>  	for (i = 0; i < MAX8997_IRQ_GROUP_NR; i++) {
> -		struct i2c_client *i2c;
> -
>  		max8997->irq_masks_cur[i] = 0xff;
>  		max8997->irq_masks_cache[i] = 0xff;
> -		i2c = get_i2c(max8997, i);
>  
> -		if (IS_ERR_OR_NULL(i2c))
> +		if (IS_ERR_OR_NULL(max8997->regmap))
>  			continue;
>  		if (max8997_mask_reg[i] == MAX8997_REG_INVALID)
>  			continue;
>  
> -		max8997_write_reg(i2c, max8997_mask_reg[i], 0xff);
> +		regmap_write(max8997->regmap, max8997_mask_reg[i], 0xff);
>  	}
>  
>  	for (i = 0; i < MAX8997_NUM_GPIO; i++) {
> -		max8997->gpio_status[i] = (max8997_read_reg(max8997->i2c,
> +		max8997->gpio_status[i] = (regmap_read(max8997->regmap,
>  						MAX8997_REG_GPIOCNTL1 + i,
>  						&val)
>  					& MAX8997_GPIO_DATA_MASK) ?
> diff --git a/drivers/mfd/max8997.c b/drivers/mfd/max8997.c
> index 5adede0..ca6f310 100644
> --- a/drivers/mfd/max8997.c
> +++ b/drivers/mfd/max8997.c
> @@ -33,6 +33,7 @@
>  #include <linux/mfd/core.h>
>  #include <linux/mfd/max8997.h>
>  #include <linux/mfd/max8997-private.h>
> +#include <linux/regmap.h>
>  
>  #define I2C_ADDR_PMIC	(0xCC >> 1)
>  #define I2C_ADDR_MUIC	(0x4A >> 1)
> @@ -57,81 +58,29 @@ static struct of_device_id max8997_pmic_dt_match[] = {
>  };
>  #endif
>  
> -int max8997_read_reg(struct i2c_client *i2c, u8 reg, u8 *dest)
> -{
> -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
> -	int ret;
> -
> -	mutex_lock(&max8997->iolock);
> -	ret = i2c_smbus_read_byte_data(i2c, reg);
> -	mutex_unlock(&max8997->iolock);
> -	if (ret < 0)
> -		return ret;
> -
> -	ret &= 0xff;
> -	*dest = ret;
> -	return 0;
> -}
> -EXPORT_SYMBOL_GPL(max8997_read_reg);
> -
> -int max8997_bulk_read(struct i2c_client *i2c, u8 reg, int count, u8 *buf)
> -{
> -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
> -	int ret;
> -
> -	mutex_lock(&max8997->iolock);
> -	ret = i2c_smbus_read_i2c_block_data(i2c, reg, count, buf);
> -	mutex_unlock(&max8997->iolock);
> -	if (ret < 0)
> -		return ret;
> -
> -	return 0;
> -}
> -EXPORT_SYMBOL_GPL(max8997_bulk_read);
> -
> -int max8997_write_reg(struct i2c_client *i2c, u8 reg, u8 value)
> -{
> -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
> -	int ret;
> -
> -	mutex_lock(&max8997->iolock);
> -	ret = i2c_smbus_write_byte_data(i2c, reg, value);
> -	mutex_unlock(&max8997->iolock);
> -	return ret;
> -}
> -EXPORT_SYMBOL_GPL(max8997_write_reg);
> -
> -int max8997_bulk_write(struct i2c_client *i2c, u8 reg, int count, u8 *buf)
> -{
> -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
> -	int ret;
> +static const struct regmap_config max8997_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.max_register = MAX8997_REG_PMIC_END,
> +};
>  
> -	mutex_lock(&max8997->iolock);
> -	ret = i2c_smbus_write_i2c_block_data(i2c, reg, count, buf);
> -	mutex_unlock(&max8997->iolock);
> -	if (ret < 0)
> -		return ret;
> +static const struct regmap_config max8997_regmap_rtc_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.max_register = MAX8997_RTC_REG_END,
> +};
>  
> -	return 0;
> -}
> -EXPORT_SYMBOL_GPL(max8997_bulk_write);
> +static const struct regmap_config max8997_regmap_haptic_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.max_register = MAX8997_HAPTIC_REG_END,
> +};
>  
> -int max8997_update_reg(struct i2c_client *i2c, u8 reg, u8 val, u8 mask)
> -{
> -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
> -	int ret;
> -
> -	mutex_lock(&max8997->iolock);
> -	ret = i2c_smbus_read_byte_data(i2c, reg);
> -	if (ret >= 0) {
> -		u8 old_val = ret & 0xff;
> -		u8 new_val = (val & mask) | (old_val & (~mask));
> -		ret = i2c_smbus_write_byte_data(i2c, reg, new_val);
> -	}
> -	mutex_unlock(&max8997->iolock);
> -	return ret;
> -}
> -EXPORT_SYMBOL_GPL(max8997_update_reg);
> +static const struct regmap_config max8997_regmap_muic_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.max_register = MAX8997_MUIC_REG_END,
> +};
>  
>  /*
>   * Only the common platform data elements for max8997 are parsed here from the
> @@ -209,11 +158,48 @@ static int max8997_i2c_probe(struct i2c_client *i2c,
>  
>  	max8997->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC);
>  	i2c_set_clientdata(max8997->rtc, max8997);
> +
>  	max8997->haptic = i2c_new_dummy(i2c->adapter, I2C_ADDR_HAPTIC);
>  	i2c_set_clientdata(max8997->haptic, max8997);
> +
>  	max8997->muic = i2c_new_dummy(i2c->adapter, I2C_ADDR_MUIC);
>  	i2c_set_clientdata(max8997->muic, max8997);
>  
> +	max8997->regmap = devm_regmap_init_i2c(i2c, &max8997_regmap_config);
> +	if (IS_ERR(max8997->regmap)) {
> +		ret = PTR_ERR(max8997->regmap);
> +		dev_err(max8997->dev,
> +				"failed to allocate register map: %d\n", ret);
> +		return ret;
> +	}
> +
> +	max8997->regmap_rtc = devm_regmap_init_i2c(max8997->rtc,
> +					&max8997_regmap_rtc_config);
> +	if (IS_ERR(max8997->regmap_rtc)) {
> +		ret = PTR_ERR(max8997->regmap_rtc);
> +		dev_err(max8997->dev,
> +				"failed to allocate register map: %d\n", ret);
> +		goto err_regmap;
> +	}
> +
> +	max8997->regmap_haptic = devm_regmap_init_i2c(max8997->haptic,
> +					&max8997_regmap_haptic_config);
> +	if (IS_ERR(max8997->regmap_haptic)) {
> +		ret = PTR_ERR(max8997->regmap_haptic);
> +		dev_err(max8997->dev,
> +				"failed to allocate register map: %d\n", ret);
> +		goto err_regmap;
> +	}
> +
> +	max8997->regmap_muic = devm_regmap_init_i2c(max8997->muic,
> +					&max8997_regmap_muic_config);
> +	if (IS_ERR(max8997->regmap_muic)) {
> +		ret = PTR_ERR(max8997->regmap_muic);
> +		dev_err(max8997->dev,
> +				"failed to allocate register map: %d\n", ret);
> +		goto err_regmap;
> +	}
> +
>  	pm_runtime_set_active(max8997->dev);
>  
>  	max8997_irq_init(max8997);
> @@ -238,6 +224,7 @@ static int max8997_i2c_probe(struct i2c_client *i2c,
>  
>  err_mfd:
>  	mfd_remove_devices(max8997->dev);
> +err_regmap:
>  	i2c_unregister_device(max8997->muic);
>  	i2c_unregister_device(max8997->haptic);
>  	i2c_unregister_device(max8997->rtc);
> @@ -423,15 +410,15 @@ static int max8997_freeze(struct device *dev)
>  	int i;
>  
>  	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_pmic); i++)
> -		max8997_read_reg(i2c, max8997_dumpaddr_pmic[i],
> +		regmap_read(max8997->regmap, max8997_dumpaddr_pmic[i],
>  				&max8997->reg_dump[i]);
>  
>  	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_muic); i++)
> -		max8997_read_reg(i2c, max8997_dumpaddr_muic[i],
> +		regmap_read(max8997->regmap_muic, max8997_dumpaddr_muic[i],
>  				&max8997->reg_dump[i + MAX8997_REG_PMIC_END]);
>  
>  	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_haptic); i++)
> -		max8997_read_reg(i2c, max8997_dumpaddr_haptic[i],
> +		regmap_read(max8997->regmap_haptic, max8997_dumpaddr_haptic[i],
>  				&max8997->reg_dump[i + MAX8997_REG_PMIC_END +
>  				MAX8997_MUIC_REG_END]);

Code looks good. Idea for another patch: could bulk read be used here?
At least some of registers have continuous addresses so maybe its worth
to read them at once?

>  
> @@ -445,15 +432,15 @@ static int max8997_restore(struct device *dev)
>  	int i;
>  
>  	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_pmic); i++)
> -		max8997_write_reg(i2c, max8997_dumpaddr_pmic[i],
> +		regmap_write(max8997->regmap, max8997_dumpaddr_pmic[i],
>  				max8997->reg_dump[i]);
>  
>  	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_muic); i++)
> -		max8997_write_reg(i2c, max8997_dumpaddr_muic[i],
> +		regmap_write(max8997->regmap_muic, max8997_dumpaddr_muic[i],
>  				max8997->reg_dump[i + MAX8997_REG_PMIC_END]);
>  
>  	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_haptic); i++)
> -		max8997_write_reg(i2c, max8997_dumpaddr_haptic[i],
> +		regmap_write(max8997->regmap_haptic, max8997_dumpaddr_haptic[i],
>  				max8997->reg_dump[i + MAX8997_REG_PMIC_END +
>  				MAX8997_MUIC_REG_END]);

As above - bulk write (if you still would like to improve things in this
driver)?

Best regards,
Krzysztof
Robert Baldyga - March 11, 2014, 2:59 p.m.
On 03/11/2014 03:32 PM, Krzysztof Kozlowski wrote:
> On Tue, 2014-03-11 at 14:58 +0100, Robert Baldyga wrote:
>> This patch modifies max8997 driver and each associated function 
>> driver, to use regmap instead of operating directly on i2c bus. It 
>> will allow to simplify IRQ handling using regmap-irq.
>> 
>> Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> --- 
>> drivers/extcon/extcon-max8997.c     |   31 ++++---- 
>> drivers/input/misc/max8997_haptic.c |   34 +++++---- 
>> drivers/leds/leds-max8997.c         |   13 ++-- 
>> drivers/mfd/max8997-irq.c           |   64 ++++++---------- 
>> drivers/mfd/max8997.c               |  143 
>> ++++++++++++++++-------------------
>> drivers/power/max8997_charger.c |   33 ++++----
>> drivers/regulator/max8997.c         |   87 ++++++++++-----------
>> drivers/rtc/rtc-max8997.c           |   56 ++++++++------
>> include/linux/mfd/max8997-private.h |   17 ++--- 9 files changed,
>> 229 insertions(+), 249 deletions(-)
> 
> I think you should also add "select REGMAP_I2C" to the main driver 
> config secion (drivers/mfd/Kconfig).

Will be fixed.

> 
> (...)
> 
>> diff --git a/drivers/mfd/max8997-irq.c b/drivers/mfd/max8997-irq.c
>>  index 43fa614..656d03b 100644 --- a/drivers/mfd/max8997-irq.c +++
>>  b/drivers/mfd/max8997-irq.c @@ -26,6 +26,7 @@ #include 
>> <linux/interrupt.h> #include <linux/mfd/max8997.h> #include 
>> <linux/mfd/max8997-private.h> +#include <linux/regmap.h>
>> 
>> static const u8 max8997_mask_reg[] = { [PMIC_INT1] = 
>> MAX8997_REG_INT1MSK, @@ -41,25 +42,6 @@ static const u8 
>> max8997_mask_reg[] = { [FLASH_STATUS] = MAX8997_REG_INVALID, };
>> 
>> -static struct i2c_client *get_i2c(struct max8997_dev *max8997, - 
>> enum max8997_irq_source src) -{ -	switch (src) { -	case PMIC_INT1 
>> ... PMIC_INT4: -		return max8997->i2c; -	case FUEL_GAUGE: - return 
>> NULL; -	case MUIC_INT1 ... MUIC_INT3: -		return max8997->muic; - 
>> case GPIO_LOW ... GPIO_HI: -		return max8997->i2c; -	case 
>> FLASH_STATUS: -		return max8997->i2c; -	default: -		return 
>> ERR_PTR(-EINVAL); -	} -} - struct max8997_irq_data { int mask;
>> enum max8997_irq_source group; @@ -124,15 +106,20 @@ static void 
>> max8997_irq_sync_unlock(struct irq_data *data) int i;
>> 
>> for (i = 0; i < MAX8997_IRQ_GROUP_NR; i++) { +		struct regmap *map;
>> u8 mask_reg = max8997_mask_reg[i]; -		struct i2c_client *i2c =
>> get_i2c(max8997, i); + +		if (i >= MUIC_INT1 && i <= MUIC_INT3) + 
>> map = max8997->regmap_muic; +		else +			map = max8997->regmap;
>> 
>> if (mask_reg == MAX8997_REG_INVALID || -				IS_ERR_OR_NULL(i2c)) + 
>> IS_ERR_OR_NULL(map)) continue; max8997->irq_masks_cache[i] = 
>> max8997->irq_masks_cur[i];
>> 
>> -		max8997_write_reg(i2c, max8997_mask_reg[i], + regmap_write(map, 
>> max8997_mask_reg[i], max8997->irq_masks_cur[i]); }
>> 
>> @@ -180,12 +167,12 @@ static struct irq_chip max8997_irq_chip = { 
>> static irqreturn_t max8997_irq_thread(int irq, void *data) {
>> struct max8997_dev *max8997 = data; -	u8
>> irq_reg[MAX8997_IRQ_GROUP_NR] = {}; -	u8 irq_src; +	unsigned int
>> irq_reg[MAX8997_IRQ_GROUP_NR] = {}; +	unsigned int irq_src; int
>> ret; int i, cur_irq;
>> 
>> -	ret = max8997_read_reg(max8997->i2c, MAX8997_REG_INTSRC, 
>> &irq_src); +	ret = regmap_read(max8997->regmap,
>> MAX8997_REG_INTSRC, &irq_src); if (ret < 0) { dev_err(max8997->dev,
>> "Failed to read interrupt source: %d\n", ret); @@ -194,8 +181,9 @@
>> static irqreturn_t max8997_irq_thread(int irq, void *data)
>> 
>> if (irq_src & MAX8997_IRQSRC_PMIC) { /* PMIC INT1 ~ INT4 */ - 
>> max8997_bulk_read(max8997->i2c, MAX8997_REG_INT1, 4, - 
>> &irq_reg[PMIC_INT1]); +		for (i = 0; i < 4; ++i) + 
>> regmap_read(max8997->regmap, +				MAX8997_REG_INT1+i, 
>> &irq_reg[PMIC_INT1+i]);
> 
> Can't you use here one bulk read instead of 4xregmap_read()?

Mixing regmap_read and regmap_bulk_read is not good idea, because the
first function returns register value as unsigned int, but the second
returns reg value to each single byte. So it would need to do some
additional operations, and makes things more complicated.

> 
> 
>> } if (irq_src & MAX8997_IRQSRC_FUELGAUGE) { /* @@ -215,8 +203,9 @@ 
>> static irqreturn_t max8997_irq_thread(int irq, void *data) } if 
>> (irq_src & MAX8997_IRQSRC_MUIC) { /* MUIC INT1 ~ INT3 */ - 
>> max8997_bulk_read(max8997->muic, MAX8997_MUIC_REG_INT1, 3, - 
>> &irq_reg[MUIC_INT1]); +		for (i = 0; i < 3; ++i) + 
>> regmap_read(max8997->regmap_muic, +				MAX8997_MUIC_REG_INT1+i, 
>> &irq_reg[MUIC_INT1+i]);
> 
> Same as above - bulk.
> 
>> } if (irq_src & MAX8997_IRQSRC_GPIO) { /* GPIO Interrupt */ @@ 
>> -225,8 +214,8 @@ static irqreturn_t max8997_irq_thread(int irq, 
>> void *data) irq_reg[GPIO_LOW] = 0; irq_reg[GPIO_HI] = 0;
>> 
>> -		max8997_bulk_read(max8997->i2c, MAX8997_REG_GPIOCNTL1, - 
>> MAX8997_NUM_GPIO, gpio_info); +		regmap_bulk_read(max8997->regmap, 
>> MAX8997_REG_GPIOCNTL1, +				gpio_info, MAX8997_NUM_GPIO); for (i = 
>> 0; i < MAX8997_NUM_GPIO; i++) { bool interrupt = false;
>> 
>> @@ -260,7 +249,7 @@ static irqreturn_t max8997_irq_thread(int irq, 
>> void *data) } if (irq_src & MAX8997_IRQSRC_FLASH) { /* Flash Status
>> Interrupt */ -		ret = max8997_read_reg(max8997->i2c, 
>> MAX8997_REG_FLASHSTATUS, +		ret = regmap_read(max8997->regmap, 
>> MAX8997_REG_FLASHSTATUS, &irq_reg[FLASH_STATUS]); }
>> 
>> @@ -312,7 +301,7 @@ int max8997_irq_init(struct max8997_dev 
>> *max8997) struct irq_domain *domain; int i; int ret; -	u8 val; + 
>> unsigned int val;
>> 
>> if (!max8997->irq) { dev_warn(max8997->dev, "No interrupt 
>> specified.\n"); @@ -323,22 +312,19 @@ int max8997_irq_init(struct 
>> max8997_dev *max8997)
>> 
>> /* Mask individual interrupt sources */ for (i = 0; i < 
>> MAX8997_IRQ_GROUP_NR; i++) { -		struct i2c_client *i2c; - 
>> max8997->irq_masks_cur[i] = 0xff; max8997->irq_masks_cache[i] = 
>> 0xff; -		i2c = get_i2c(max8997, i);
>> 
>> -		if (IS_ERR_OR_NULL(i2c)) +		if (IS_ERR_OR_NULL(max8997->regmap))
>> continue; if (max8997_mask_reg[i] == MAX8997_REG_INVALID)
>> continue;
>> 
>> -		max8997_write_reg(i2c, max8997_mask_reg[i], 0xff); + 
>> regmap_write(max8997->regmap, max8997_mask_reg[i], 0xff); }
>> 
>> for (i = 0; i < MAX8997_NUM_GPIO; i++) { - max8997->gpio_status[i] 
>> = (max8997_read_reg(max8997->i2c, + max8997->gpio_status[i] = 
>> (regmap_read(max8997->regmap, MAX8997_REG_GPIOCNTL1 + i, &val) & 
>> MAX8997_GPIO_DATA_MASK) ? diff --git a/drivers/mfd/max8997.c 
>> b/drivers/mfd/max8997.c index 5adede0..ca6f310 100644 --- 
>> a/drivers/mfd/max8997.c +++ b/drivers/mfd/max8997.c @@ -33,6 +33,7 
>> @@ #include <linux/mfd/core.h> #include <linux/mfd/max8997.h> 
>> #include <linux/mfd/max8997-private.h> +#include <linux/regmap.h>
>> 
>> #define I2C_ADDR_PMIC	(0xCC >> 1) #define I2C_ADDR_MUIC	(0x4A >> 1)
>> @@ -57,81 +58,29 @@ static struct of_device_id 
>> max8997_pmic_dt_match[] = { }; #endif
>> 
>> -int max8997_read_reg(struct i2c_client *i2c, u8 reg, u8 *dest) -{
>>  -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c); -	int
>> ret; - -	mutex_lock(&max8997->iolock); -	ret = 
>> i2c_smbus_read_byte_data(i2c, reg); - 
>> mutex_unlock(&max8997->iolock); -	if (ret < 0) -		return ret; - - 
>> ret &= 0xff; -	*dest = ret; -	return 0; -} 
>> -EXPORT_SYMBOL_GPL(max8997_read_reg); - -int 
>> max8997_bulk_read(struct i2c_client *i2c, u8 reg, int count, u8 
>> *buf) -{ -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
>> - int ret; - -	mutex_lock(&max8997->iolock); -	ret = 
>> i2c_smbus_read_i2c_block_data(i2c, reg, count, buf); - 
>> mutex_unlock(&max8997->iolock); -	if (ret < 0) -		return ret; - - 
>> return 0; -} -EXPORT_SYMBOL_GPL(max8997_bulk_read); - -int 
>> max8997_write_reg(struct i2c_client *i2c, u8 reg, u8 value) -{ - 
>> struct max8997_dev *max8997 = i2c_get_clientdata(i2c); -	int ret; -
>> -	mutex_lock(&max8997->iolock); -	ret = 
>> i2c_smbus_write_byte_data(i2c, reg, value); - 
>> mutex_unlock(&max8997->iolock); -	return ret; -} 
>> -EXPORT_SYMBOL_GPL(max8997_write_reg); - -int 
>> max8997_bulk_write(struct i2c_client *i2c, u8 reg, int count, u8 
>> *buf) -{ -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
>> - int ret; +static const struct regmap_config max8997_regmap_config
>> = { +	.reg_bits = 8, +	.val_bits = 8, +	.max_register = 
>> MAX8997_REG_PMIC_END, +};
>> 
>> -	mutex_lock(&max8997->iolock); -	ret = 
>> i2c_smbus_write_i2c_block_data(i2c, reg, count, buf); - 
>> mutex_unlock(&max8997->iolock); -	if (ret < 0) -		return ret; 
>> +static const struct regmap_config max8997_regmap_rtc_config = { + 
>> .reg_bits = 8, +	.val_bits = 8, +	.max_register = 
>> MAX8997_RTC_REG_END, +};
>> 
>> -	return 0; -} -EXPORT_SYMBOL_GPL(max8997_bulk_write); +static 
>> const struct regmap_config max8997_regmap_haptic_config = { + 
>> .reg_bits = 8, +	.val_bits = 8, +	.max_register = 
>> MAX8997_HAPTIC_REG_END, +};
>> 
>> -int max8997_update_reg(struct i2c_client *i2c, u8 reg, u8 val, u8 
>> mask) -{ -	struct max8997_dev *max8997 = i2c_get_clientdata(i2c); -
>> int ret; - -	mutex_lock(&max8997->iolock); -	ret = 
>> i2c_smbus_read_byte_data(i2c, reg); -	if (ret >= 0) { -		u8
>> old_val = ret & 0xff; -		u8 new_val = (val & mask) | (old_val &
>> (~mask)); - ret = i2c_smbus_write_byte_data(i2c, reg, new_val); -	}
>> - mutex_unlock(&max8997->iolock); -	return ret; -} 
>> -EXPORT_SYMBOL_GPL(max8997_update_reg); +static const struct 
>> regmap_config max8997_regmap_muic_config = { +	.reg_bits = 8, + 
>> .val_bits = 8, +	.max_register = MAX8997_MUIC_REG_END, +};
>> 
>> /* * Only the common platform data elements for max8997 are parsed 
>> here from the @@ -209,11 +158,48 @@ static int 
>> max8997_i2c_probe(struct i2c_client *i2c,
>> 
>> max8997->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC); 
>> i2c_set_clientdata(max8997->rtc, max8997); + max8997->haptic = 
>> i2c_new_dummy(i2c->adapter, I2C_ADDR_HAPTIC); 
>> i2c_set_clientdata(max8997->haptic, max8997); + max8997->muic = 
>> i2c_new_dummy(i2c->adapter, I2C_ADDR_MUIC); 
>> i2c_set_clientdata(max8997->muic, max8997);
>> 
>> +	max8997->regmap = devm_regmap_init_i2c(i2c, 
>> &max8997_regmap_config); +	if (IS_ERR(max8997->regmap)) { +		ret = 
>> PTR_ERR(max8997->regmap); +		dev_err(max8997->dev, +				"failed to 
>> allocate register map: %d\n", ret); +		return ret; +	} + + 
>> max8997->regmap_rtc = devm_regmap_init_i2c(max8997->rtc, + 
>> &max8997_regmap_rtc_config); +	if (IS_ERR(max8997->regmap_rtc)) {
>> + ret = PTR_ERR(max8997->regmap_rtc); +		dev_err(max8997->dev, + 
>> "failed to allocate register map: %d\n", ret); +		goto err_regmap;
>>  +	} + +	max8997->regmap_haptic = 
>> devm_regmap_init_i2c(max8997->haptic, + 
>> &max8997_regmap_haptic_config); +	if 
>> (IS_ERR(max8997->regmap_haptic)) { +		ret = 
>> PTR_ERR(max8997->regmap_haptic); +		dev_err(max8997->dev, + "failed
>> to allocate register map: %d\n", ret); +		goto err_regmap; +	} + +
>> max8997->regmap_muic = devm_regmap_init_i2c(max8997->muic, +
>> &max8997_regmap_muic_config); +	if (IS_ERR(max8997->regmap_muic)) {
>> +		ret = PTR_ERR(max8997->regmap_muic); +		dev_err(max8997->dev, +
>> "failed to allocate register map: %d\n", ret); +		goto err_regmap;
>> +	} + pm_runtime_set_active(max8997->dev);
>> 
>> max8997_irq_init(max8997); @@ -238,6 +224,7 @@ static int 
>> max8997_i2c_probe(struct i2c_client *i2c,
>> 
>> err_mfd: mfd_remove_devices(max8997->dev); +err_regmap: 
>> i2c_unregister_device(max8997->muic); 
>> i2c_unregister_device(max8997->haptic); 
>> i2c_unregister_device(max8997->rtc); @@ -423,15 +410,15 @@ static 
>> int max8997_freeze(struct device *dev) int i;
>> 
>> for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_pmic); i++) - 
>> max8997_read_reg(i2c, max8997_dumpaddr_pmic[i], + 
>> regmap_read(max8997->regmap, max8997_dumpaddr_pmic[i], 
>> &max8997->reg_dump[i]);
>> 
>> for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_muic); i++) - 
>> max8997_read_reg(i2c, max8997_dumpaddr_muic[i], + 
>> regmap_read(max8997->regmap_muic, max8997_dumpaddr_muic[i], 
>> &max8997->reg_dump[i + MAX8997_REG_PMIC_END]);
>> 
>> for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_haptic); i++) - 
>> max8997_read_reg(i2c, max8997_dumpaddr_haptic[i], + 
>> regmap_read(max8997->regmap_haptic, max8997_dumpaddr_haptic[i], 
>> &max8997->reg_dump[i + MAX8997_REG_PMIC_END + 
>> MAX8997_MUIC_REG_END]);
> 
> Code looks good. Idea for another patch: could bulk read be used 
> here? At least some of registers have continuous addresses so maybe 
> its worth to read them at once?

It's problematic, because address ranges of dumped registers are not
continuous. So it would need to call regmap_bulk_read in loop, which
gives a small gain and complicates the code. I think there is no purpose
to do it. It's better and keep it simple.

>> 
>> @@ -445,15 +432,15 @@ static int max8997_restore(struct device 
>> *dev) int i;
>> 
>> for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_pmic); i++) - 
>> max8997_write_reg(i2c, max8997_dumpaddr_pmic[i], + 
>> regmap_write(max8997->regmap, max8997_dumpaddr_pmic[i], 
>> max8997->reg_dump[i]);
>> 
>> for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_muic); i++) - 
>> max8997_write_reg(i2c, max8997_dumpaddr_muic[i], + 
>> regmap_write(max8997->regmap_muic, max8997_dumpaddr_muic[i], 
>> max8997->reg_dump[i + MAX8997_REG_PMIC_END]);
>> 
>> for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_haptic); i++) - 
>> max8997_write_reg(i2c, max8997_dumpaddr_haptic[i], + 
>> regmap_write(max8997->regmap_haptic, max8997_dumpaddr_haptic[i], 
>> max8997->reg_dump[i + MAX8997_REG_PMIC_END + 
>> MAX8997_MUIC_REG_END]);
> 
> As above - bulk write (if you still would like to improve things in 
> this driver)?
> 

Thanks,
Robert
Krzysztof Kozlowski - March 11, 2014, 3:20 p.m.
On Tue, 2014-03-11 at 15:59 +0100, Robert Baldyga wrote:
> >> @@ -180,12 +167,12 @@ static struct irq_chip max8997_irq_chip = { 
> >> static irqreturn_t max8997_irq_thread(int irq, void *data) {
> >> struct max8997_dev *max8997 = data; -	u8
> >> irq_reg[MAX8997_IRQ_GROUP_NR] = {}; -	u8 irq_src; +	unsigned int
> >> irq_reg[MAX8997_IRQ_GROUP_NR] = {}; +	unsigned int irq_src; int
> >> ret; int i, cur_irq;
> >> 
> >> -	ret = max8997_read_reg(max8997->i2c, MAX8997_REG_INTSRC, 
> >> &irq_src); +	ret = regmap_read(max8997->regmap,
> >> MAX8997_REG_INTSRC, &irq_src); if (ret < 0) { dev_err(max8997->dev,
> >> "Failed to read interrupt source: %d\n", ret); @@ -194,8 +181,9 @@
> >> static irqreturn_t max8997_irq_thread(int irq, void *data)
> >> 
> >> if (irq_src & MAX8997_IRQSRC_PMIC) { /* PMIC INT1 ~ INT4 */ - 
> >> max8997_bulk_read(max8997->i2c, MAX8997_REG_INT1, 4, - 
> >> &irq_reg[PMIC_INT1]); +		for (i = 0; i < 4; ++i) + 
> >> regmap_read(max8997->regmap, +				MAX8997_REG_INT1+i, 
> >> &irq_reg[PMIC_INT1+i]);
> > 
> > Can't you use here one bulk read instead of 4xregmap_read()?
> 
> Mixing regmap_read and regmap_bulk_read is not good idea, because the
> first function returns register value as unsigned int, but the second
> returns reg value to each single byte. So it would need to do some
> additional operations, and makes things more complicated.

The only mixing I see would be in reading FLASHSTATUS register which
could be resolved with:

if (irq_src & MAX8997_IRQSRC_FLASH) {
       /* Flash Status Interrupt */
       unsigned int data;
       ret = regmap_read(max8997->regmap, MAX8997_REG_FLASHSTATUS,
		       &data);
       irq_reg[FLASH_STATUS] = data;
}

This isn't more complicated than replacing bulk read with a loop :).

Best regards,
Krzysztof

Patch

diff --git a/drivers/extcon/extcon-max8997.c b/drivers/extcon/extcon-max8997.c
index 6a00464..f258c08 100644
--- a/drivers/extcon/extcon-max8997.c
+++ b/drivers/extcon/extcon-max8997.c
@@ -27,6 +27,7 @@ 
 #include <linux/mfd/max8997-private.h>
 #include <linux/extcon.h>
 #include <linux/irqdomain.h>
+#include <linux/regmap.h>
 
 #define	DEV_NAME			"max8997-muic"
 #define	DELAY_MS_DEFAULT		20000		/* unit: millisecond */
@@ -116,7 +117,7 @@  enum max8997_muic_charger_type {
 
 struct max8997_muic_info {
 	struct device *dev;
-	struct i2c_client *muic;
+	struct max8997_dev *max8997;
 	struct extcon_dev *edev;
 	int prev_cable_type;
 	int prev_chg_type;
@@ -190,10 +191,10 @@  static int max8997_muic_set_debounce_time(struct max8997_muic_info *info,
 	case ADC_DEBOUNCE_TIME_10MS:
 	case ADC_DEBOUNCE_TIME_25MS:
 	case ADC_DEBOUNCE_TIME_38_62MS:
-		ret = max8997_update_reg(info->muic,
+		ret = regmap_update_bits(info->max8997->regmap_muic,
 					  MAX8997_MUIC_REG_CONTROL3,
-					  time << CONTROL3_ADCDBSET_SHIFT,
-					  CONTROL3_ADCDBSET_MASK);
+					  CONTROL3_ADCDBSET_MASK,
+					  time << CONTROL3_ADCDBSET_SHIFT);
 		if (ret) {
 			dev_err(info->dev, "failed to set ADC debounce time\n");
 			return ret;
@@ -228,8 +229,8 @@  static int max8997_muic_set_path(struct max8997_muic_info *info,
 	else
 		ctrl1 = CONTROL1_SW_OPEN;
 
-	ret = max8997_update_reg(info->muic,
-			MAX8997_MUIC_REG_CONTROL1, ctrl1, COMP_SW_MASK);
+	ret = regmap_update_bits(info->max8997->regmap_muic,
+			MAX8997_MUIC_REG_CONTROL1, COMP_SW_MASK, ctrl1);
 	if (ret < 0) {
 		dev_err(info->dev, "failed to update MUIC register\n");
 		return ret;
@@ -240,9 +241,9 @@  static int max8997_muic_set_path(struct max8997_muic_info *info,
 	else
 		ctrl2 |= CONTROL2_LOWPWR_MASK;	/* LowPwr=1, CPEn=0 */
 
-	ret = max8997_update_reg(info->muic,
-			MAX8997_MUIC_REG_CONTROL2, ctrl2,
-			CONTROL2_LOWPWR_MASK | CONTROL2_CPEN_MASK);
+	ret = regmap_update_bits(info->max8997->regmap_muic,
+			MAX8997_MUIC_REG_CONTROL2,
+			CONTROL2_LOWPWR_MASK | CONTROL2_CPEN_MASK, ctrl2);
 	if (ret < 0) {
 		dev_err(info->dev, "failed to update MUIC register\n");
 		return ret;
@@ -543,8 +544,8 @@  static void max8997_muic_irq_work(struct work_struct *work)
 		if (info->irq == muic_irqs[i].virq)
 			irq_type = muic_irqs[i].irq;
 
-	ret = max8997_bulk_read(info->muic, MAX8997_MUIC_REG_STATUS1,
-				2, info->status);
+	ret = regmap_bulk_read(info->max8997->regmap_muic,
+				MAX8997_MUIC_REG_STATUS1, info->status, 2);
 	if (ret) {
 		dev_err(info->dev, "failed to read muic register\n");
 		mutex_unlock(&info->mutex);
@@ -605,8 +606,8 @@  static int max8997_muic_detect_dev(struct max8997_muic_info *info)
 	mutex_lock(&info->mutex);
 
 	/* Read STATUSx register to detect accessory */
-	ret = max8997_bulk_read(info->muic,
-			MAX8997_MUIC_REG_STATUS1, 2, info->status);
+	ret = regmap_bulk_read(info->max8997->regmap_muic,
+			MAX8997_MUIC_REG_STATUS1, info->status, 2);
 	if (ret) {
 		dev_err(info->dev, "failed to read MUIC register\n");
 		mutex_unlock(&info->mutex);
@@ -667,7 +668,7 @@  static int max8997_muic_probe(struct platform_device *pdev)
 	}
 
 	info->dev = &pdev->dev;
-	info->muic = max8997->muic;
+	info->max8997 = max8997;
 
 	platform_set_drvdata(pdev, info);
 	mutex_init(&info->mutex);
@@ -721,7 +722,7 @@  static int max8997_muic_probe(struct platform_device *pdev)
 
 		/* Initialize registers according to platform data */
 		for (i = 0; i < muic_pdata->num_init_data; i++) {
-			max8997_write_reg(info->muic,
+			regmap_write(info->max8997->regmap_muic,
 					muic_pdata->init_data[i].addr,
 					muic_pdata->init_data[i].data);
 		}
diff --git a/drivers/input/misc/max8997_haptic.c b/drivers/input/misc/max8997_haptic.c
index 1fea548..d3f7079 100644
--- a/drivers/input/misc/max8997_haptic.c
+++ b/drivers/input/misc/max8997_haptic.c
@@ -31,6 +31,7 @@ 
 #include <linux/mfd/max8997-private.h>
 #include <linux/mfd/max8997.h>
 #include <linux/regulator/consumer.h>
+#include <linux/regmap.h>
 
 /* Haptic configuration 2 register */
 #define MAX8997_MOTOR_TYPE_SHIFT	7
@@ -45,7 +46,7 @@ 
 
 struct max8997_haptic {
 	struct device *dev;
-	struct i2c_client *client;
+	struct max8997_dev *max8997;
 	struct input_dev *input_dev;
 	struct regulator *regulator;
 
@@ -86,19 +87,19 @@  static int max8997_haptic_set_duty_cycle(struct max8997_haptic *chip)
 		}
 		switch (chip->internal_mode_pattern) {
 		case 0:
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_SIGPWMDC1, duty_index);
 			break;
 		case 1:
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_SIGPWMDC2, duty_index);
 			break;
 		case 2:
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_SIGPWMDC3, duty_index);
 			break;
 		case 3:
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_SIGPWMDC4, duty_index);
 			break;
 		default:
@@ -115,50 +116,51 @@  static void max8997_haptic_configure(struct max8997_haptic *chip)
 	value = chip->type << MAX8997_MOTOR_TYPE_SHIFT |
 		chip->enabled << MAX8997_ENABLE_SHIFT |
 		chip->mode << MAX8997_MODE_SHIFT | chip->pwm_divisor;
-	max8997_write_reg(chip->client, MAX8997_HAPTIC_REG_CONF2, value);
+	regmap_write(chip->max8997->regmap_haptic,
+		MAX8997_HAPTIC_REG_CONF2, value);
 
 	if (chip->mode == MAX8997_INTERNAL_MODE && chip->enabled) {
 		value = chip->internal_mode_pattern << MAX8997_CYCLE_SHIFT |
 			chip->internal_mode_pattern << MAX8997_SIG_PERIOD_SHIFT |
 			chip->internal_mode_pattern << MAX8997_SIG_DUTY_SHIFT |
 			chip->internal_mode_pattern << MAX8997_PWM_DUTY_SHIFT;
-		max8997_write_reg(chip->client,
+		regmap_write(chip->max8997->regmap_haptic,
 			MAX8997_HAPTIC_REG_DRVCONF, value);
 
 		switch (chip->internal_mode_pattern) {
 		case 0:
 			value = chip->pattern_cycle << 4;
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_CYCLECONF1, value);
 			value = chip->pattern_signal_period;
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_SIGCONF1, value);
 			break;
 
 		case 1:
 			value = chip->pattern_cycle;
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_CYCLECONF1, value);
 			value = chip->pattern_signal_period;
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_SIGCONF2, value);
 			break;
 
 		case 2:
 			value = chip->pattern_cycle << 4;
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_CYCLECONF2, value);
 			value = chip->pattern_signal_period;
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_SIGCONF3, value);
 			break;
 
 		case 3:
 			value = chip->pattern_cycle;
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_CYCLECONF2, value);
 			value = chip->pattern_signal_period;
-			max8997_write_reg(chip->client,
+			regmap_write(chip->max8997->regmap_haptic,
 				MAX8997_HAPTIC_REG_SIGCONF4, value);
 			break;
 
@@ -267,7 +269,7 @@  static int max8997_haptic_probe(struct platform_device *pdev)
 	INIT_WORK(&chip->work, max8997_haptic_play_effect_work);
 	mutex_init(&chip->mutex);
 
-	chip->client = iodev->haptic;
+	chip->max8997 = iodev;
 	chip->dev = &pdev->dev;
 	chip->input_dev = input_dev;
 	chip->pwm_period = haptic_pdata->pwm_period;
diff --git a/drivers/leds/leds-max8997.c b/drivers/leds/leds-max8997.c
index f449a8b..e2da8f2 100644
--- a/drivers/leds/leds-max8997.c
+++ b/drivers/leds/leds-max8997.c
@@ -18,6 +18,7 @@ 
 #include <linux/mfd/max8997.h>
 #include <linux/mfd/max8997-private.h>
 #include <linux/platform_device.h>
+#include <linux/regmap.h>
 
 #define MAX8997_LED_FLASH_SHIFT			3
 #define MAX8997_LED_FLASH_CUR_MASK		0xf8
@@ -53,7 +54,6 @@  static void max8997_led_set_mode(struct max8997_led *led,
 			enum max8997_led_mode mode)
 {
 	int ret;
-	struct i2c_client *client = led->iodev->i2c;
 	u8 mask = 0, val;
 
 	switch (mode) {
@@ -89,8 +89,8 @@  static void max8997_led_set_mode(struct max8997_led *led,
 	}
 
 	if (mask) {
-		ret = max8997_update_reg(client, MAX8997_REG_LEN_CNTL, val,
-					 mask);
+		ret = regmap_update_bits(led->iodev->regmap,
+					MAX8997_REG_LEN_CNTL, mask, val);
 		if (ret)
 			dev_err(led->iodev->dev,
 				"failed to update register(%d)\n", ret);
@@ -102,7 +102,6 @@  static void max8997_led_set_mode(struct max8997_led *led,
 static void max8997_led_enable(struct max8997_led *led, bool enable)
 {
 	int ret;
-	struct i2c_client *client = led->iodev->i2c;
 	u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
 
 	if (led->enabled == enable)
@@ -110,7 +109,8 @@  static void max8997_led_enable(struct max8997_led *led, bool enable)
 
 	val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
 
-	ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
+	ret = regmap_update_bits(led->iodev->regmap,
+				MAX8997_REG_BOOST_CNTL, mask, val);
 	if (ret)
 		dev_err(led->iodev->dev,
 			"failed to update register(%d)\n", ret);
@@ -122,7 +122,6 @@  static void max8997_led_set_current(struct max8997_led *led,
 				enum led_brightness value)
 {
 	int ret;
-	struct i2c_client *client = led->iodev->i2c;
 	u8 val = 0, mask = 0, reg = 0;
 
 	switch (led->led_mode) {
@@ -143,7 +142,7 @@  static void max8997_led_set_current(struct max8997_led *led,
 	}
 
 	if (mask) {
-		ret = max8997_update_reg(client, reg, val, mask);
+		ret = regmap_update_bits(led->iodev->regmap, reg, mask, val);
 		if (ret)
 			dev_err(led->iodev->dev,
 				"failed to update register(%d)\n", ret);
diff --git a/drivers/mfd/max8997-irq.c b/drivers/mfd/max8997-irq.c
index 43fa614..656d03b 100644
--- a/drivers/mfd/max8997-irq.c
+++ b/drivers/mfd/max8997-irq.c
@@ -26,6 +26,7 @@ 
 #include <linux/interrupt.h>
 #include <linux/mfd/max8997.h>
 #include <linux/mfd/max8997-private.h>
+#include <linux/regmap.h>
 
 static const u8 max8997_mask_reg[] = {
 	[PMIC_INT1] = MAX8997_REG_INT1MSK,
@@ -41,25 +42,6 @@  static const u8 max8997_mask_reg[] = {
 	[FLASH_STATUS] = MAX8997_REG_INVALID,
 };
 
-static struct i2c_client *get_i2c(struct max8997_dev *max8997,
-				enum max8997_irq_source src)
-{
-	switch (src) {
-	case PMIC_INT1 ... PMIC_INT4:
-		return max8997->i2c;
-	case FUEL_GAUGE:
-		return NULL;
-	case MUIC_INT1 ... MUIC_INT3:
-		return max8997->muic;
-	case GPIO_LOW ... GPIO_HI:
-		return max8997->i2c;
-	case FLASH_STATUS:
-		return max8997->i2c;
-	default:
-		return ERR_PTR(-EINVAL);
-	}
-}
-
 struct max8997_irq_data {
 	int mask;
 	enum max8997_irq_source group;
@@ -124,15 +106,20 @@  static void max8997_irq_sync_unlock(struct irq_data *data)
 	int i;
 
 	for (i = 0; i < MAX8997_IRQ_GROUP_NR; i++) {
+		struct regmap *map;
 		u8 mask_reg = max8997_mask_reg[i];
-		struct i2c_client *i2c = get_i2c(max8997, i);
+
+		if (i >= MUIC_INT1 && i <= MUIC_INT3)
+			map = max8997->regmap_muic;
+		else
+			map = max8997->regmap;
 
 		if (mask_reg == MAX8997_REG_INVALID ||
-				IS_ERR_OR_NULL(i2c))
+				IS_ERR_OR_NULL(map))
 			continue;
 		max8997->irq_masks_cache[i] = max8997->irq_masks_cur[i];
 
-		max8997_write_reg(i2c, max8997_mask_reg[i],
+		regmap_write(map, max8997_mask_reg[i],
 				max8997->irq_masks_cur[i]);
 	}
 
@@ -180,12 +167,12 @@  static struct irq_chip max8997_irq_chip = {
 static irqreturn_t max8997_irq_thread(int irq, void *data)
 {
 	struct max8997_dev *max8997 = data;
-	u8 irq_reg[MAX8997_IRQ_GROUP_NR] = {};
-	u8 irq_src;
+	unsigned int irq_reg[MAX8997_IRQ_GROUP_NR] = {};
+	unsigned int irq_src;
 	int ret;
 	int i, cur_irq;
 
-	ret = max8997_read_reg(max8997->i2c, MAX8997_REG_INTSRC, &irq_src);
+	ret = regmap_read(max8997->regmap, MAX8997_REG_INTSRC, &irq_src);
 	if (ret < 0) {
 		dev_err(max8997->dev, "Failed to read interrupt source: %d\n",
 				ret);
@@ -194,8 +181,9 @@  static irqreturn_t max8997_irq_thread(int irq, void *data)
 
 	if (irq_src & MAX8997_IRQSRC_PMIC) {
 		/* PMIC INT1 ~ INT4 */
-		max8997_bulk_read(max8997->i2c, MAX8997_REG_INT1, 4,
-				&irq_reg[PMIC_INT1]);
+		for (i = 0; i < 4; ++i)
+			regmap_read(max8997->regmap,
+				MAX8997_REG_INT1+i, &irq_reg[PMIC_INT1+i]);
 	}
 	if (irq_src & MAX8997_IRQSRC_FUELGAUGE) {
 		/*
@@ -215,8 +203,9 @@  static irqreturn_t max8997_irq_thread(int irq, void *data)
 	}
 	if (irq_src & MAX8997_IRQSRC_MUIC) {
 		/* MUIC INT1 ~ INT3 */
-		max8997_bulk_read(max8997->muic, MAX8997_MUIC_REG_INT1, 3,
-				&irq_reg[MUIC_INT1]);
+		for (i = 0; i < 3; ++i)
+			regmap_read(max8997->regmap_muic,
+				MAX8997_MUIC_REG_INT1+i, &irq_reg[MUIC_INT1+i]);
 	}
 	if (irq_src & MAX8997_IRQSRC_GPIO) {
 		/* GPIO Interrupt */
@@ -225,8 +214,8 @@  static irqreturn_t max8997_irq_thread(int irq, void *data)
 		irq_reg[GPIO_LOW] = 0;
 		irq_reg[GPIO_HI] = 0;
 
-		max8997_bulk_read(max8997->i2c, MAX8997_REG_GPIOCNTL1,
-				MAX8997_NUM_GPIO, gpio_info);
+		regmap_bulk_read(max8997->regmap, MAX8997_REG_GPIOCNTL1,
+				gpio_info, MAX8997_NUM_GPIO);
 		for (i = 0; i < MAX8997_NUM_GPIO; i++) {
 			bool interrupt = false;
 
@@ -260,7 +249,7 @@  static irqreturn_t max8997_irq_thread(int irq, void *data)
 	}
 	if (irq_src & MAX8997_IRQSRC_FLASH) {
 		/* Flash Status Interrupt */
-		ret = max8997_read_reg(max8997->i2c, MAX8997_REG_FLASHSTATUS,
+		ret = regmap_read(max8997->regmap, MAX8997_REG_FLASHSTATUS,
 				&irq_reg[FLASH_STATUS]);
 	}
 
@@ -312,7 +301,7 @@  int max8997_irq_init(struct max8997_dev *max8997)
 	struct irq_domain *domain;
 	int i;
 	int ret;
-	u8 val;
+	unsigned int val;
 
 	if (!max8997->irq) {
 		dev_warn(max8997->dev, "No interrupt specified.\n");
@@ -323,22 +312,19 @@  int max8997_irq_init(struct max8997_dev *max8997)
 
 	/* Mask individual interrupt sources */
 	for (i = 0; i < MAX8997_IRQ_GROUP_NR; i++) {
-		struct i2c_client *i2c;
-
 		max8997->irq_masks_cur[i] = 0xff;
 		max8997->irq_masks_cache[i] = 0xff;
-		i2c = get_i2c(max8997, i);
 
-		if (IS_ERR_OR_NULL(i2c))
+		if (IS_ERR_OR_NULL(max8997->regmap))
 			continue;
 		if (max8997_mask_reg[i] == MAX8997_REG_INVALID)
 			continue;
 
-		max8997_write_reg(i2c, max8997_mask_reg[i], 0xff);
+		regmap_write(max8997->regmap, max8997_mask_reg[i], 0xff);
 	}
 
 	for (i = 0; i < MAX8997_NUM_GPIO; i++) {
-		max8997->gpio_status[i] = (max8997_read_reg(max8997->i2c,
+		max8997->gpio_status[i] = (regmap_read(max8997->regmap,
 						MAX8997_REG_GPIOCNTL1 + i,
 						&val)
 					& MAX8997_GPIO_DATA_MASK) ?
diff --git a/drivers/mfd/max8997.c b/drivers/mfd/max8997.c
index 5adede0..ca6f310 100644
--- a/drivers/mfd/max8997.c
+++ b/drivers/mfd/max8997.c
@@ -33,6 +33,7 @@ 
 #include <linux/mfd/core.h>
 #include <linux/mfd/max8997.h>
 #include <linux/mfd/max8997-private.h>
+#include <linux/regmap.h>
 
 #define I2C_ADDR_PMIC	(0xCC >> 1)
 #define I2C_ADDR_MUIC	(0x4A >> 1)
@@ -57,81 +58,29 @@  static struct of_device_id max8997_pmic_dt_match[] = {
 };
 #endif
 
-int max8997_read_reg(struct i2c_client *i2c, u8 reg, u8 *dest)
-{
-	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
-	int ret;
-
-	mutex_lock(&max8997->iolock);
-	ret = i2c_smbus_read_byte_data(i2c, reg);
-	mutex_unlock(&max8997->iolock);
-	if (ret < 0)
-		return ret;
-
-	ret &= 0xff;
-	*dest = ret;
-	return 0;
-}
-EXPORT_SYMBOL_GPL(max8997_read_reg);
-
-int max8997_bulk_read(struct i2c_client *i2c, u8 reg, int count, u8 *buf)
-{
-	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
-	int ret;
-
-	mutex_lock(&max8997->iolock);
-	ret = i2c_smbus_read_i2c_block_data(i2c, reg, count, buf);
-	mutex_unlock(&max8997->iolock);
-	if (ret < 0)
-		return ret;
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(max8997_bulk_read);
-
-int max8997_write_reg(struct i2c_client *i2c, u8 reg, u8 value)
-{
-	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
-	int ret;
-
-	mutex_lock(&max8997->iolock);
-	ret = i2c_smbus_write_byte_data(i2c, reg, value);
-	mutex_unlock(&max8997->iolock);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(max8997_write_reg);
-
-int max8997_bulk_write(struct i2c_client *i2c, u8 reg, int count, u8 *buf)
-{
-	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
-	int ret;
+static const struct regmap_config max8997_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = MAX8997_REG_PMIC_END,
+};
 
-	mutex_lock(&max8997->iolock);
-	ret = i2c_smbus_write_i2c_block_data(i2c, reg, count, buf);
-	mutex_unlock(&max8997->iolock);
-	if (ret < 0)
-		return ret;
+static const struct regmap_config max8997_regmap_rtc_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = MAX8997_RTC_REG_END,
+};
 
-	return 0;
-}
-EXPORT_SYMBOL_GPL(max8997_bulk_write);
+static const struct regmap_config max8997_regmap_haptic_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = MAX8997_HAPTIC_REG_END,
+};
 
-int max8997_update_reg(struct i2c_client *i2c, u8 reg, u8 val, u8 mask)
-{
-	struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
-	int ret;
-
-	mutex_lock(&max8997->iolock);
-	ret = i2c_smbus_read_byte_data(i2c, reg);
-	if (ret >= 0) {
-		u8 old_val = ret & 0xff;
-		u8 new_val = (val & mask) | (old_val & (~mask));
-		ret = i2c_smbus_write_byte_data(i2c, reg, new_val);
-	}
-	mutex_unlock(&max8997->iolock);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(max8997_update_reg);
+static const struct regmap_config max8997_regmap_muic_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = MAX8997_MUIC_REG_END,
+};
 
 /*
  * Only the common platform data elements for max8997 are parsed here from the
@@ -209,11 +158,48 @@  static int max8997_i2c_probe(struct i2c_client *i2c,
 
 	max8997->rtc = i2c_new_dummy(i2c->adapter, I2C_ADDR_RTC);
 	i2c_set_clientdata(max8997->rtc, max8997);
+
 	max8997->haptic = i2c_new_dummy(i2c->adapter, I2C_ADDR_HAPTIC);
 	i2c_set_clientdata(max8997->haptic, max8997);
+
 	max8997->muic = i2c_new_dummy(i2c->adapter, I2C_ADDR_MUIC);
 	i2c_set_clientdata(max8997->muic, max8997);
 
+	max8997->regmap = devm_regmap_init_i2c(i2c, &max8997_regmap_config);
+	if (IS_ERR(max8997->regmap)) {
+		ret = PTR_ERR(max8997->regmap);
+		dev_err(max8997->dev,
+				"failed to allocate register map: %d\n", ret);
+		return ret;
+	}
+
+	max8997->regmap_rtc = devm_regmap_init_i2c(max8997->rtc,
+					&max8997_regmap_rtc_config);
+	if (IS_ERR(max8997->regmap_rtc)) {
+		ret = PTR_ERR(max8997->regmap_rtc);
+		dev_err(max8997->dev,
+				"failed to allocate register map: %d\n", ret);
+		goto err_regmap;
+	}
+
+	max8997->regmap_haptic = devm_regmap_init_i2c(max8997->haptic,
+					&max8997_regmap_haptic_config);
+	if (IS_ERR(max8997->regmap_haptic)) {
+		ret = PTR_ERR(max8997->regmap_haptic);
+		dev_err(max8997->dev,
+				"failed to allocate register map: %d\n", ret);
+		goto err_regmap;
+	}
+
+	max8997->regmap_muic = devm_regmap_init_i2c(max8997->muic,
+					&max8997_regmap_muic_config);
+	if (IS_ERR(max8997->regmap_muic)) {
+		ret = PTR_ERR(max8997->regmap_muic);
+		dev_err(max8997->dev,
+				"failed to allocate register map: %d\n", ret);
+		goto err_regmap;
+	}
+
 	pm_runtime_set_active(max8997->dev);
 
 	max8997_irq_init(max8997);
@@ -238,6 +224,7 @@  static int max8997_i2c_probe(struct i2c_client *i2c,
 
 err_mfd:
 	mfd_remove_devices(max8997->dev);
+err_regmap:
 	i2c_unregister_device(max8997->muic);
 	i2c_unregister_device(max8997->haptic);
 	i2c_unregister_device(max8997->rtc);
@@ -423,15 +410,15 @@  static int max8997_freeze(struct device *dev)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_pmic); i++)
-		max8997_read_reg(i2c, max8997_dumpaddr_pmic[i],
+		regmap_read(max8997->regmap, max8997_dumpaddr_pmic[i],
 				&max8997->reg_dump[i]);
 
 	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_muic); i++)
-		max8997_read_reg(i2c, max8997_dumpaddr_muic[i],
+		regmap_read(max8997->regmap_muic, max8997_dumpaddr_muic[i],
 				&max8997->reg_dump[i + MAX8997_REG_PMIC_END]);
 
 	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_haptic); i++)
-		max8997_read_reg(i2c, max8997_dumpaddr_haptic[i],
+		regmap_read(max8997->regmap_haptic, max8997_dumpaddr_haptic[i],
 				&max8997->reg_dump[i + MAX8997_REG_PMIC_END +
 				MAX8997_MUIC_REG_END]);
 
@@ -445,15 +432,15 @@  static int max8997_restore(struct device *dev)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_pmic); i++)
-		max8997_write_reg(i2c, max8997_dumpaddr_pmic[i],
+		regmap_write(max8997->regmap, max8997_dumpaddr_pmic[i],
 				max8997->reg_dump[i]);
 
 	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_muic); i++)
-		max8997_write_reg(i2c, max8997_dumpaddr_muic[i],
+		regmap_write(max8997->regmap_muic, max8997_dumpaddr_muic[i],
 				max8997->reg_dump[i + MAX8997_REG_PMIC_END]);
 
 	for (i = 0; i < ARRAY_SIZE(max8997_dumpaddr_haptic); i++)
-		max8997_write_reg(i2c, max8997_dumpaddr_haptic[i],
+		regmap_write(max8997->regmap_haptic, max8997_dumpaddr_haptic[i],
 				max8997->reg_dump[i + MAX8997_REG_PMIC_END +
 				MAX8997_MUIC_REG_END]);
 
diff --git a/drivers/power/max8997_charger.c b/drivers/power/max8997_charger.c
index 4bdedfe..43d8481 100644
--- a/drivers/power/max8997_charger.c
+++ b/drivers/power/max8997_charger.c
@@ -26,6 +26,7 @@ 
 #include <linux/power_supply.h>
 #include <linux/mfd/max8997.h>
 #include <linux/mfd/max8997-private.h>
+#include <linux/regmap.h>
 
 struct charger_data {
 	struct device *dev;
@@ -46,14 +47,14 @@  static int max8997_battery_get_property(struct power_supply *psy,
 {
 	struct charger_data *charger = container_of(psy,
 			struct charger_data, battery);
-	struct i2c_client *i2c = charger->iodev->i2c;
 	int ret;
-	u8 reg;
+	unsigned int reg;
 
 	switch (psp) {
 	case POWER_SUPPLY_PROP_STATUS:
 		val->intval = 0;
-		ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
+		ret = regmap_read(charger->iodev->regmap,
+				MAX8997_REG_STATUS4, &reg);
 		if (ret)
 			return ret;
 		if ((reg & (1 << 0)) == 0x1)
@@ -62,7 +63,8 @@  static int max8997_battery_get_property(struct power_supply *psy,
 		break;
 	case POWER_SUPPLY_PROP_PRESENT:
 		val->intval = 0;
-		ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
+		ret = regmap_read(charger->iodev->regmap,
+				MAX8997_REG_STATUS4, &reg);
 		if (ret)
 			return ret;
 		if ((reg & (1 << 2)) == 0x0)
@@ -71,7 +73,8 @@  static int max8997_battery_get_property(struct power_supply *psy,
 		break;
 	case POWER_SUPPLY_PROP_ONLINE:
 		val->intval = 0;
-		ret = max8997_read_reg(i2c, MAX8997_REG_STATUS4, &reg);
+		ret = regmap_read(charger->iodev->regmap,
+				MAX8997_REG_STATUS4, &reg);
 		if (ret)
 			return ret;
 		/* DCINOK */
@@ -103,8 +106,8 @@  static int max8997_battery_probe(struct platform_device *pdev)
 		if (val > 0xf)
 			val = 0xf;
 
-		ret = max8997_update_reg(iodev->i2c,
-				MAX8997_REG_MBCCTRL5, val, 0xf);
+		ret = regmap_update_bits(iodev->regmap,
+				MAX8997_REG_MBCCTRL5, 0xf, val);
 		if (ret < 0) {
 			dev_err(&pdev->dev, "Cannot use i2c bus.\n");
 			return ret;
@@ -113,20 +116,20 @@  static int max8997_battery_probe(struct platform_device *pdev)
 
 	switch (pdata->timeout) {
 	case 5:
-		ret = max8997_update_reg(iodev->i2c, MAX8997_REG_MBCCTRL1,
-				0x2 << 4, 0x7 << 4);
+		ret = regmap_update_bits(iodev->regmap,
+				MAX8997_REG_MBCCTRL1, 0x7 << 4, 0x2 << 4);
 		break;
 	case 6:
-		ret = max8997_update_reg(iodev->i2c, MAX8997_REG_MBCCTRL1,
-				0x3 << 4, 0x7 << 4);
+		ret = regmap_update_bits(iodev->regmap,
+				MAX8997_REG_MBCCTRL1, 0x7 << 4, 0x3 << 4);
 		break;
 	case 7:
-		ret = max8997_update_reg(iodev->i2c, MAX8997_REG_MBCCTRL1,
-				0x4 << 4, 0x7 << 4);
+		ret = regmap_update_bits(iodev->regmap,
+				MAX8997_REG_MBCCTRL1, 0x7 << 4, 0x4 << 4);
 		break;
 	case 0:
-		ret = max8997_update_reg(iodev->i2c, MAX8997_REG_MBCCTRL1,
-				0x7 << 4, 0x7 << 4);
+		ret = regmap_update_bits(iodev->regmap,
+				MAX8997_REG_MBCCTRL1, 0x7 << 4, 0x7 << 4);
 		break;
 	default:
 		dev_err(&pdev->dev, "incorrect timeout value (%d)\n",
diff --git a/drivers/regulator/max8997.c b/drivers/regulator/max8997.c
index 2d618fc..4001ed7 100644
--- a/drivers/regulator/max8997.c
+++ b/drivers/regulator/max8997.c
@@ -33,6 +33,7 @@ 
 #include <linux/mfd/max8997.h>
 #include <linux/mfd/max8997-private.h>
 #include <linux/regulator/of_regulator.h>
+#include <linux/regmap.h>
 
 struct max8997_data {
 	struct device *dev;
@@ -51,7 +52,7 @@  struct max8997_data {
 	int buck125_gpioindex;
 	bool ignore_gpiodvs_side_effect;
 
-	u8 saved_states[MAX8997_REG_MAX];
+	unsigned int saved_states[MAX8997_REG_MAX];
 };
 
 static const unsigned int safeoutvolt[] = {
@@ -258,15 +259,14 @@  static int max8997_get_enable_register(struct regulator_dev *rdev,
 static int max8997_reg_is_enabled(struct regulator_dev *rdev)
 {
 	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
-	struct i2c_client *i2c = max8997->iodev->i2c;
 	int ret, reg, mask, pattern;
-	u8 val;
+	unsigned int val;
 
 	ret = max8997_get_enable_register(rdev, &reg, &mask, &pattern);
 	if (ret)
 		return ret;
 
-	ret = max8997_read_reg(i2c, reg, &val);
+	ret = regmap_read(max8997->iodev->regmap, reg, &val);
 	if (ret)
 		return ret;
 
@@ -276,27 +276,25 @@  static int max8997_reg_is_enabled(struct regulator_dev *rdev)
 static int max8997_reg_enable(struct regulator_dev *rdev)
 {
 	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
-	struct i2c_client *i2c = max8997->iodev->i2c;
 	int ret, reg, mask, pattern;
 
 	ret = max8997_get_enable_register(rdev, &reg, &mask, &pattern);
 	if (ret)
 		return ret;
 
-	return max8997_update_reg(i2c, reg, pattern, mask);
+	return regmap_update_bits(max8997->iodev->regmap, reg, mask, pattern);
 }
 
 static int max8997_reg_disable(struct regulator_dev *rdev)
 {
 	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
-	struct i2c_client *i2c = max8997->iodev->i2c;
 	int ret, reg, mask, pattern;
 
 	ret = max8997_get_enable_register(rdev, &reg, &mask, &pattern);
 	if (ret)
 		return ret;
 
-	return max8997_update_reg(i2c, reg, ~pattern, mask);
+	return regmap_update_bits(max8997->iodev->regmap, reg, mask, ~pattern);
 }
 
 static int max8997_get_voltage_register(struct regulator_dev *rdev,
@@ -368,15 +366,14 @@  static int max8997_get_voltage_register(struct regulator_dev *rdev,
 static int max8997_get_voltage_sel(struct regulator_dev *rdev)
 {
 	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
-	struct i2c_client *i2c = max8997->iodev->i2c;
 	int reg, shift, mask, ret;
-	u8 val;
+	unsigned int val;
 
 	ret = max8997_get_voltage_register(rdev, &reg, &shift, &mask);
 	if (ret)
 		return ret;
 
-	ret = max8997_read_reg(i2c, reg, &val);
+	ret = regmap_read(max8997->iodev->regmap, reg, &val);
 	if (ret)
 		return ret;
 
@@ -413,7 +410,6 @@  static int max8997_set_voltage_charger_cv(struct regulator_dev *rdev,
 		int min_uV, int max_uV, unsigned *selector)
 {
 	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
-	struct i2c_client *i2c = max8997->iodev->i2c;
 	int rid = rdev_get_id(rdev);
 	int lb, ub;
 	int reg, shift = 0, mask, ret = 0;
@@ -455,7 +451,8 @@  static int max8997_set_voltage_charger_cv(struct regulator_dev *rdev,
 
 	*selector = val;
 
-	ret = max8997_update_reg(i2c, reg, val << shift, mask);
+	ret = regmap_update_bits(max8997->iodev->regmap,
+				reg, mask, val << shift);
 
 	return ret;
 }
@@ -468,7 +465,6 @@  static int max8997_set_voltage_ldobuck(struct regulator_dev *rdev,
 		int min_uV, int max_uV, unsigned *selector)
 {
 	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
-	struct i2c_client *i2c = max8997->iodev->i2c;
 	const struct voltage_map_desc *desc;
 	int rid = rdev_get_id(rdev);
 	int i, reg, shift, mask, ret;
@@ -500,7 +496,8 @@  static int max8997_set_voltage_ldobuck(struct regulator_dev *rdev,
 	if (ret)
 		return ret;
 
-	ret = max8997_update_reg(i2c, reg, i << shift, mask << shift);
+	ret = regmap_update_bits(max8997->iodev->regmap,
+				reg, mask << shift, i << shift);
 	*selector = i;
 
 	return ret;
@@ -710,7 +707,6 @@  static int max8997_set_voltage_safeout_sel(struct regulator_dev *rdev,
 					   unsigned selector)
 {
 	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
-	struct i2c_client *i2c = max8997->iodev->i2c;
 	int rid = rdev_get_id(rdev);
 	int reg, shift = 0, mask, ret;
 
@@ -721,13 +717,13 @@  static int max8997_set_voltage_safeout_sel(struct regulator_dev *rdev,
 	if (ret)
 		return ret;
 
-	return max8997_update_reg(i2c, reg, selector << shift, mask << shift);
+	return regmap_update_bits(max8997->iodev->regmap,
+				reg, mask << shift, selector << shift);
 }
 
 static int max8997_reg_disable_suspend(struct regulator_dev *rdev)
 {
 	struct max8997_data *max8997 = rdev_get_drvdata(rdev);
-	struct i2c_client *i2c = max8997->iodev->i2c;
 	int ret, reg, mask, pattern;
 	int rid = rdev_get_id(rdev);
 
@@ -735,20 +731,22 @@  static int max8997_reg_disable_suspend(struct regulator_dev *rdev)
 	if (ret)
 		return ret;
 
-	max8997_read_reg(i2c, reg, &max8997->saved_states[rid]);
+	regmap_read(max8997->iodev->regmap,
+			reg, &max8997->saved_states[rid]);
 
 	if (rid == MAX8997_LDO1 ||
 			rid == MAX8997_LDO10 ||
 			rid == MAX8997_LDO21) {
 		dev_dbg(&rdev->dev, "Conditional Power-Off for %s\n",
 				rdev->desc->name);
-		return max8997_update_reg(i2c, reg, 0x40, mask);
+		return regmap_update_bits(max8997->iodev->regmap,
+				reg, mask, 0x40);
 	}
 
 	dev_dbg(&rdev->dev, "Full Power-Off for %s (%xh -> %xh)\n",
 			rdev->desc->name, max8997->saved_states[rid] & mask,
 			(~pattern) & mask);
-	return max8997_update_reg(i2c, reg, ~pattern, mask);
+	return regmap_update_bits(max8997->iodev->regmap, reg, mask, ~pattern);
 }
 
 static struct regulator_ops max8997_ldo_ops = {
@@ -1032,7 +1030,6 @@  static int max8997_pmic_probe(struct platform_device *pdev)
 	struct regulator_config config = { };
 	struct regulator_dev **rdev;
 	struct max8997_data *max8997;
-	struct i2c_client *i2c;
 	int i, ret, size, nr_dvs;
 	u8 max_buck1 = 0, max_buck2 = 0, max_buck5 = 0;
 
@@ -1062,7 +1059,6 @@  static int max8997_pmic_probe(struct platform_device *pdev)
 	max8997->iodev = iodev;
 	max8997->num_regulators = pdata->num_regulators;
 	platform_set_drvdata(pdev, max8997);
-	i2c = max8997->iodev->i2c;
 
 	max8997->buck125_gpioindex = pdata->buck125_default_idx;
 	max8997->buck1_gpiodvs = pdata->buck1_gpiodvs;
@@ -1112,25 +1108,25 @@  static int max8997_pmic_probe(struct platform_device *pdev)
 
 	/* For the safety, set max voltage before setting up */
 	for (i = 0; i < 8; i++) {
-		max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS1 + i,
-				max_buck1, 0x3f);
-		max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS1 + i,
-				max_buck2, 0x3f);
-		max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS1 + i,
-				max_buck5, 0x3f);
+		regmap_update_bits(max8997->iodev->regmap,
+				MAX8997_REG_BUCK1DVS1 + i, 0x3f, max_buck1);
+		regmap_update_bits(max8997->iodev->regmap,
+				MAX8997_REG_BUCK2DVS1 + i, 0x3f, max_buck2);
+		regmap_update_bits(max8997->iodev->regmap,
+				MAX8997_REG_BUCK5DVS1 + i, 0x3f, max_buck5);
 	}
 
 	/* Initialize all the DVS related BUCK registers */
 	for (i = 0; i < nr_dvs; i++) {
-		max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS1 + i,
-				max8997->buck1_vol[i],
-				0x3f);
-		max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS1 + i,
-				max8997->buck2_vol[i],
-				0x3f);
-		max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS1 + i,
-				max8997->buck5_vol[i],
-				0x3f);
+		regmap_update_bits(max8997->iodev->regmap,
+				MAX8997_REG_BUCK1DVS1 + i,
+				0x3f, max8997->buck1_vol[i]);
+		regmap_update_bits(max8997->iodev->regmap,
+				MAX8997_REG_BUCK2DVS1 + i,
+				0x3f, max8997->buck2_vol[i]);
+		regmap_update_bits(max8997->iodev->regmap,
+				MAX8997_REG_BUCK5DVS1 + i,
+				0x3f, max8997->buck5_vol[i]);
 	}
 
 	/*
@@ -1174,16 +1170,17 @@  static int max8997_pmic_probe(struct platform_device *pdev)
 	}
 
 	/* DVS-GPIO disabled */
-	max8997_update_reg(i2c, MAX8997_REG_BUCK1CTRL, (pdata->buck1_gpiodvs) ?
-			(1 << 1) : (0 << 1), 1 << 1);
-	max8997_update_reg(i2c, MAX8997_REG_BUCK2CTRL, (pdata->buck2_gpiodvs) ?
-			(1 << 1) : (0 << 1), 1 << 1);
-	max8997_update_reg(i2c, MAX8997_REG_BUCK5CTRL, (pdata->buck5_gpiodvs) ?
-			(1 << 1) : (0 << 1), 1 << 1);
+	regmap_update_bits(max8997->iodev->regmap, MAX8997_REG_BUCK1CTRL,
+			1 << 1, (pdata->buck1_gpiodvs) ? (1 << 1) : (0 << 1));
+	regmap_update_bits(max8997->iodev->regmap, MAX8997_REG_BUCK2CTRL,
+			1 << 1, (pdata->buck2_gpiodvs) ? (1 << 1) : (0 << 1));
+	regmap_update_bits(max8997->iodev->regmap, MAX8997_REG_BUCK5CTRL,
+			1 << 1, (pdata->buck5_gpiodvs) ? (1 << 1) : (0 << 1));
 
 	/* Misc Settings */
 	max8997->ramp_delay = 10; /* set 10mV/us, which is the default */
-	max8997_write_reg(i2c, MAX8997_REG_BUCKRAMP, (0xf << 4) | 0x9);
+	regmap_write(max8997->iodev->regmap,
+			MAX8997_REG_BUCKRAMP, (0xf << 4) | 0x9);
 
 	for (i = 0; i < pdata->num_regulators; i++) {
 		const struct voltage_map_desc *desc;
diff --git a/drivers/rtc/rtc-max8997.c b/drivers/rtc/rtc-max8997.c
index 0777c01..b866f7d5 100644
--- a/drivers/rtc/rtc-max8997.c
+++ b/drivers/rtc/rtc-max8997.c
@@ -20,6 +20,7 @@ 
 #include <linux/platform_device.h>
 #include <linux/mfd/max8997-private.h>
 #include <linux/irqdomain.h>
+#include <linux/regmap.h>
 
 /* Module parameter for WTSR function control */
 static int wtsr_en = 1;
@@ -68,7 +69,6 @@  enum {
 struct max8997_rtc_info {
 	struct device		*dev;
 	struct max8997_dev	*max8997;
-	struct i2c_client	*rtc;
 	struct rtc_device	*rtc_dev;
 	struct mutex		lock;
 	int virq;
@@ -118,8 +118,8 @@  static inline int max8997_rtc_set_update_reg(struct max8997_rtc_info *info)
 {
 	int ret;
 
-	ret = max8997_write_reg(info->rtc, MAX8997_RTC_UPDATE1,
-						RTC_UDR_MASK);
+	ret = regmap_write(info->max8997->regmap_rtc,
+				MAX8997_RTC_UPDATE1, RTC_UDR_MASK);
 	if (ret < 0)
 		dev_err(info->dev, "%s: fail to write update reg(%d)\n",
 				__func__, ret);
@@ -140,7 +140,8 @@  static int max8997_rtc_read_time(struct device *dev, struct rtc_time *tm)
 	int ret;
 
 	mutex_lock(&info->lock);
-	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_SEC, RTC_NR_TIME, data);
+	ret = regmap_bulk_read(info->max8997->regmap_rtc,
+				MAX8997_RTC_SEC, data, RTC_NR_TIME);
 	mutex_unlock(&info->lock);
 
 	if (ret < 0) {
@@ -166,7 +167,8 @@  static int max8997_rtc_set_time(struct device *dev, struct rtc_time *tm)
 
 	mutex_lock(&info->lock);
 
-	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_SEC, RTC_NR_TIME, data);
+	ret = regmap_bulk_write(info->max8997->regmap_rtc,
+				MAX8997_RTC_SEC, data, RTC_NR_TIME);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write time reg(%d)\n", __func__,
 				ret);
@@ -183,13 +185,13 @@  static int max8997_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	struct max8997_rtc_info *info = dev_get_drvdata(dev);
 	u8 data[RTC_NR_TIME];
-	u8 val;
+	unsigned int val;
 	int i, ret;
 
 	mutex_lock(&info->lock);
 
-	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
-			data);
+	ret = regmap_bulk_read(info->max8997->regmap_rtc,
+				MAX8997_RTC_ALARM1_SEC, data, RTC_NR_TIME);
 	if (ret < 0) {
 		dev_err(info->dev, "%s:%d fail to read alarm reg(%d)\n",
 				__func__, __LINE__, ret);
@@ -207,7 +209,8 @@  static int max8997_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	}
 
 	alrm->pending = 0;
-	ret = max8997_read_reg(info->max8997->i2c, MAX8997_REG_STATUS1, &val);
+	ret = regmap_read(info->max8997->regmap_rtc,
+			       MAX8997_REG_STATUS1, &val);
 	if (ret < 0) {
 		dev_err(info->dev, "%s:%d fail to read status1 reg(%d)\n",
 				__func__, __LINE__, ret);
@@ -230,8 +233,8 @@  static int max8997_rtc_stop_alarm(struct max8997_rtc_info *info)
 	if (!mutex_is_locked(&info->lock))
 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
 
-	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
-				data);
+	ret = regmap_bulk_read(info->max8997->regmap_rtc,
+				MAX8997_RTC_ALARM1_SEC, data, RTC_NR_TIME);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
 				__func__, ret);
@@ -241,8 +244,8 @@  static int max8997_rtc_stop_alarm(struct max8997_rtc_info *info)
 	for (i = 0; i < RTC_NR_TIME; i++)
 		data[i] &= ~ALARM_ENABLE_MASK;
 
-	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
-				 data);
+	ret = regmap_bulk_write(info->max8997->regmap_rtc,
+				 MAX8997_RTC_ALARM1_SEC, data, RTC_NR_TIME);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
 				__func__, ret);
@@ -262,8 +265,8 @@  static int max8997_rtc_start_alarm(struct max8997_rtc_info *info)
 	if (!mutex_is_locked(&info->lock))
 		dev_warn(info->dev, "%s: should have mutex locked\n", __func__);
 
-	ret = max8997_bulk_read(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
-				data);
+	ret = regmap_bulk_read(info->max8997->regmap_rtc,
+				MAX8997_RTC_ALARM1_SEC, data, RTC_NR_TIME);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
 				__func__, ret);
@@ -281,8 +284,8 @@  static int max8997_rtc_start_alarm(struct max8997_rtc_info *info)
 	if (data[RTC_DATE] & 0x1f)
 		data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
 
-	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
-				 data);
+	ret = regmap_bulk_write(info->max8997->regmap_rtc,
+				 MAX8997_RTC_ALARM1_SEC, data, RTC_NR_TIME);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
 				__func__, ret);
@@ -313,8 +316,8 @@  static int max8997_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	if (ret < 0)
 		goto out;
 
-	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_ALARM1_SEC, RTC_NR_TIME,
-				data);
+	ret = regmap_bulk_write(info->max8997->regmap_rtc,
+				 MAX8997_RTC_ALARM1_SEC, data, RTC_NR_TIME);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
 				__func__, ret);
@@ -385,7 +388,8 @@  static void max8997_rtc_enable_wtsr(struct max8997_rtc_info *info, bool enable)
 	dev_info(info->dev, "%s: %s WTSR\n", __func__,
 			enable ? "enable" : "disable");
 
-	ret = max8997_update_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, val, mask);
+	ret = regmap_update_bits(info->max8997->regmap_rtc,
+				 MAX8997_RTC_WTSR_SMPL, mask, val);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to update WTSR reg(%d)\n",
 				__func__, ret);
@@ -398,7 +402,7 @@  static void max8997_rtc_enable_wtsr(struct max8997_rtc_info *info, bool enable)
 static void max8997_rtc_enable_smpl(struct max8997_rtc_info *info, bool enable)
 {
 	int ret;
-	u8 val, mask;
+	unsigned int val, mask;
 
 	if (!smpl_en)
 		return;
@@ -413,7 +417,8 @@  static void max8997_rtc_enable_smpl(struct max8997_rtc_info *info, bool enable)
 	dev_info(info->dev, "%s: %s SMPL\n", __func__,
 			enable ? "enable" : "disable");
 
-	ret = max8997_update_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, val, mask);
+	ret = regmap_update_bits(info->max8997->regmap_rtc,
+				 MAX8997_RTC_WTSR_SMPL, mask, val);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to update SMPL reg(%d)\n",
 				__func__, ret);
@@ -423,7 +428,8 @@  static void max8997_rtc_enable_smpl(struct max8997_rtc_info *info, bool enable)
 	max8997_rtc_set_update_reg(info);
 
 	val = 0;
-	max8997_read_reg(info->rtc, MAX8997_RTC_WTSR_SMPL, &val);
+	regmap_read(info->max8997->regmap_rtc,
+			 MAX8997_RTC_WTSR_SMPL, &val);
 	pr_info("%s: WTSR_SMPL(0x%02x)\n", __func__, val);
 }
 
@@ -438,7 +444,8 @@  static int max8997_rtc_init_reg(struct max8997_rtc_info *info)
 
 	info->rtc_24hr_mode = 1;
 
-	ret = max8997_bulk_write(info->rtc, MAX8997_RTC_CTRLMASK, 2, data);
+	ret = regmap_bulk_write(info->max8997->regmap_rtc,
+				 MAX8997_RTC_CTRLMASK, data, 2);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write controlm reg(%d)\n",
 				__func__, ret);
@@ -463,7 +470,6 @@  static int max8997_rtc_probe(struct platform_device *pdev)
 	mutex_init(&info->lock);
 	info->dev = &pdev->dev;
 	info->max8997 = max8997;
-	info->rtc = max8997->rtc;
 
 	platform_set_drvdata(pdev, info);
 
diff --git a/include/linux/mfd/max8997-private.h b/include/linux/mfd/max8997-private.h
index 78c76cd..ea80ef8 100644
--- a/include/linux/mfd/max8997-private.h
+++ b/include/linux/mfd/max8997-private.h
@@ -309,6 +309,8 @@  enum max8997_rtc_reg {
 	MAX8997_RTC_ALARM2_MONTH	= 0x22,
 	MAX8997_RTC_ALARM2_YEAR		= 0x23,
 	MAX8997_RTC_ALARM2_DAY_OF_MONTH	= 0x24,
+
+	MAX8997_RTC_REG_END		= 0x25,
 };
 
 enum max8997_irq_source {
@@ -390,6 +392,11 @@  struct max8997_dev {
 	unsigned long type;
 	struct platform_device *battery; /* battery control (not fuel gauge) */
 
+	struct regmap *regmap;
+	struct regmap *regmap_rtc;
+	struct regmap *regmap_haptic;
+	struct regmap *regmap_muic;
+
 	int irq;
 	int ono;
 	struct irq_domain *irq_domain;
@@ -398,7 +405,7 @@  struct max8997_dev {
 	int irq_masks_cache[MAX8997_IRQ_GROUP_NR];
 
 	/* For hibernation */
-	u8 reg_dump[MAX8997_REG_PMIC_END + MAX8997_MUIC_REG_END +
+	unsigned int reg_dump[MAX8997_REG_PMIC_END + MAX8997_MUIC_REG_END +
 		MAX8997_HAPTIC_REG_END];
 
 	bool gpio_status[MAX8997_NUM_GPIO];
@@ -413,14 +420,6 @@  extern int max8997_irq_init(struct max8997_dev *max8997);
 extern void max8997_irq_exit(struct max8997_dev *max8997);
 extern int max8997_irq_resume(struct max8997_dev *max8997);
 
-extern int max8997_read_reg(struct i2c_client *i2c, u8 reg, u8 *dest);
-extern int max8997_bulk_read(struct i2c_client *i2c, u8 reg, int count,
-				u8 *buf);
-extern int max8997_write_reg(struct i2c_client *i2c, u8 reg, u8 value);
-extern int max8997_bulk_write(struct i2c_client *i2c, u8 reg, int count,
-				u8 *buf);
-extern int max8997_update_reg(struct i2c_client *i2c, u8 reg, u8 val, u8 mask);
-
 #define MAX8997_GPIO_INT_BOTH	(0x3 << 4)
 #define MAX8997_GPIO_INT_RISE	(0x2 << 4)
 #define MAX8997_GPIO_INT_FALL	(0x1 << 4)