PMIC: MAX77686: Add support for MAX77686

Message ID 1337610057-5777-1-git-send-email-rajeshwari.s@samsung.com
State New
Headers show

Commit Message

Rajeshwari Shinde May 21, 2012, 2:20 p.m.
This patch adds driver and register definitions for PMIC chip
MAX77686.

Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
---
 drivers/power/Makefile   |    1 +
 drivers/power/max77686.c |  225 ++++++++++++++++++++++++++++++++++++++++++++++
 include/max77686.h       |  115 +++++++++++++++++++++++
 3 files changed, 341 insertions(+), 0 deletions(-)
 create mode 100644 drivers/power/max77686.c
 create mode 100644 include/max77686.h

Comments

Lukasz Majewski May 22, 2012, 6:50 a.m. | #1
Hi Rajeshwari,

> This patch adds driver and register definitions for PMIC chip
> MAX77686.

Why don't use the PMIC framework? Please look into drivers/misc/pmic_*
for examples.

For now there is a support for MAX899{7|8} chips for Samsung platforms.

> 
> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
> Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
> ---
>  drivers/power/Makefile   |    1 +
>  drivers/power/max77686.c |  225
> ++++++++++++++++++++++++++++++++++++++++++++++
> include/max77686.h       |  115 +++++++++++++++++++++++ 3 files
> changed, 341 insertions(+), 0 deletions(-) create mode 100644
> drivers/power/max77686.c create mode 100644 include/max77686.h
> 
> diff --git a/drivers/power/Makefile b/drivers/power/Makefile
> index 6bf388c..b4ffc1d 100644
> --- a/drivers/power/Makefile
> +++ b/drivers/power/Makefile
> @@ -26,6 +26,7 @@ include $(TOPDIR)/config.mk
>  LIB 	:= $(obj)libpower.o
>  
>  COBJS-$(CONFIG_FTPMU010_POWER)	+= ftpmu010.o
> +COBJS-$(CONFIG_MAX77686_POWER)	+= max77686.o
>  COBJS-$(CONFIG_TPS6586X_POWER)	+= tps6586x.o
>  COBJS-$(CONFIG_TWL4030_POWER)	+= twl4030.o
>  COBJS-$(CONFIG_TWL6030_POWER)	+= twl6030.o
> diff --git a/drivers/power/max77686.c b/drivers/power/max77686.c
> new file mode 100644
> index 0000000..cf58611
> --- /dev/null
> +++ b/drivers/power/max77686.c
> @@ -0,0 +1,225 @@
> +/*
> + * Copyright (C) 2012 Samsung Electronics
> + * Alim Akhtar <alim.akhtar@samsung.com>
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +#include <common.h>
> +#include <i2c.h>
> +#include <max77686.h>
> +
> +/*
> + * Max77686 parameters values
> + * see max77686.h for parameters details
> + */
> +struct max77686_para max77686_param[] = {/*{regnum, vol_addr,
> vol_bitpos,
> +	vol_bitmask, reg_enaddr, reg_enbitpos, reg_enbitmask,
> reg_enbiton,
> +	reg_enbitoff, vol_min, vol_div}*/
> +	{PMIC_BUCK1, 0x11, 0x0, 0x3F, 0x10, 0x0, 0x3, 0x3, 0x0, 750,
> 50000},
> +	{PMIC_BUCK2, 0x14, 0x0, 0xFF, 0x12, 0x4, 0x3, 0x1, 0x0, 600,
> 12500},
> +	{PMIC_BUCK3, 0x1E, 0x0, 0xFF, 0x1C, 0x4, 0x3, 0x1, 0x0, 600,
> 12500},
> +	{PMIC_BUCK4, 0x28, 0x0, 0xFF, 0x26, 0x4, 0x3, 0x1, 0x0, 600,
> 12500},
> +	{PMIC_BUCK5, 0x31, 0x0, 0x3F, 0x30, 0x0, 0x3, 0x3, 0x0, 750,
> 50000},
> +	{PMIC_BUCK6, 0x33, 0x0, 0x3F, 0x32, 0x0, 0x3, 0x3, 0x0, 750,
> 50000},
> +	{PMIC_BUCK7, 0x35, 0x0, 0x3F, 0x34, 0x0, 0x3, 0x3, 0x0, 750,
> 50000},
> +	{PMIC_BUCK8, 0x37, 0x0, 0x3F, 0x36, 0x0, 0x3, 0x3, 0x0, 750,
> 50000},
> +	{PMIC_BUCK9, 0x39, 0x0, 0x3F, 0x38, 0x0, 0x3, 0x3, 0x0, 750,
> 50000},
> +	{PMIC_LDO1,  0x40, 0x0, 0x3F, 0x40, 0x6, 0x3, 0x3, 0x0, 800,
> 25000},
> +	{PMIC_LDO2,  0x41, 0x0, 0x3F, 0x41, 0x6, 0x3, 0x1, 0x0, 800,
> 25000},
> +	{PMIC_LDO3,  0x42, 0x0, 0x3F, 0x42, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO4,  0x43, 0x0, 0x3F, 0x43, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO5,  0x44, 0x0, 0x3F, 0x44, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO6,  0x45, 0x0, 0x3F, 0x45, 0x6, 0x3, 0x1, 0x0, 800,
> 25000},
> +	{PMIC_LDO7,  0x46, 0x0, 0x3F, 0x46, 0x6, 0x3, 0x1, 0x0, 800,
> 25000},
> +	{PMIC_LDO8,  0x47, 0x0, 0x3F, 0x47, 0x6, 0x3, 0x1, 0x0, 800,
> 25000},
> +	{PMIC_LDO9,  0x48, 0x0, 0x3F, 0x48, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO10, 0x49, 0x0, 0x3F, 0x49, 0x6, 0x3, 0x1, 0x0, 800,
> 50000},
> +	{PMIC_LDO11, 0x4A, 0x0, 0x3F, 0x4A, 0x6, 0x3, 0x1, 0x0, 800,
> 50000},
> +	{PMIC_LDO12, 0x4B, 0x0, 0x3F, 0x4B, 0x6, 0x3, 0x1, 0x0, 800,
> 50000},
> +	{PMIC_LDO13, 0x4C, 0x0, 0x3F, 0x4C, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO14, 0x4D, 0x0, 0x3F, 0x4D, 0x6, 0x3, 0x1, 0x0, 800,
> 50000},
> +	{PMIC_LDO15, 0x4E, 0x0, 0x3F, 0x4E, 0x6, 0x3, 0x1, 0x0, 800,
> 25000},
> +	{PMIC_LDO16, 0x4F, 0x0, 0x3F, 0x4F, 0x6, 0x3, 0x1, 0x0, 800,
> 50000},
> +	{PMIC_LDO17, 0x50, 0x0, 0x3F, 0x50, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO18, 0x51, 0x0, 0x3F, 0x51, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO19, 0x52, 0x0, 0x3F, 0x52, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO20, 0x53, 0x0, 0x3F, 0x53, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO21, 0x54, 0x0, 0x3F, 0x54, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO22, 0x55, 0x0, 0x3F, 0x55, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO23, 0x56, 0x0, 0x3F, 0x56, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO24, 0x57, 0x0, 0x3F, 0x57, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO25, 0x58, 0x0, 0x3F, 0x58, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_LDO26, 0x59, 0x0, 0x3F, 0x59, 0x6, 0x3, 0x3, 0x0, 800,
> 50000},
> +	{PMIC_EN32KHZ_CP, 0x0, 0x0, 0x0, 0x7F, 0x1, 0x1, 0x1, 0x0,
> 0x0, 0x0}, +};

Frankly speaking it looks a bit unreadable (especially without specs
attached).

> +
> +/*
> + * Write a value to a register
> + *
> + * @param chip_addr	i2c addr for max77686
> + * @param reg		reg number to write
> + * @param val		value to be written
> + *
> + */
> +static inline int max77686_i2c_write(unsigned char chip_addr,
> +					unsigned int reg, unsigned
> char val) +{
> +	return i2c_write(chip_addr, reg, 1, &val, 1);
> +}

This "write register" is also available in the PMIC framework.

> +
> +/*
> + * Read a value from a register
> + *
> + * @param chip_addr	i2c addr for max77686
> + * @param reg		reg number to write
> + * @param val		value to be written
> + *
> + */
> +static inline int max77686_i2c_read(unsigned char chip_addr,
> +					unsigned int reg, unsigned

It is also available on the PMIC framework.

> char *val) +{
> +	return i2c_read(chip_addr, reg, 1, val, 1);
> +}
> +
> +/*
> + * Enable the max77686 register
> + *
> + * @param reg		register number of buck/ldo to be
> enabled
> + * @param enable	enable or disable bit
> + *
> + *			REG_DISABLE = 0,
> +			needed to set the buck/ldo enable bit OFF
> + * @return		Return 0 if ok, else -1
> + */
> +static int max77686_enablereg(enum max77686_regnum reg, int enable)
> +{
> +	struct max77686_para *pmic;
> +	unsigned char read_data;
> +	int ret;
> +
> +	pmic = &max77686_param[reg];
> +
> +	ret = max77686_i2c_read(MAX77686_I2C_ADDR, pmic->vol_addr,
> &read_data);
> +	if (ret != 0) {
> +		debug("max77686 i2c read failed.\n");
> +		return -1;
> +	}
> +
> +	if (enable == REG_DISABLE) {
> +		clrbits_8(&read_data,
> +				pmic->reg_enbitmask <<
> pmic->reg_enbitpos);
> +	} else {
> +		clrsetbits_8(&read_data,
> +				pmic->reg_enbitmask <<
> pmic->reg_enbitpos,
> +				pmic->reg_enbiton <<
> pmic->reg_enbitpos);
> +	}
> +
> +	ret = max77686_i2c_write(MAX77686_I2C_ADDR,
> +				 pmic->reg_enaddr, read_data);
> +	if (ret != 0) {
> +		debug("max77686 i2c write failed.\n");
> +		return -1;
> +	}
> +
> +	return 0;
> +}

Please look into the PMIC section of ./board/samsung/trats/trats.c for
reference. Moreover changing/enabling regulator function is already
available at pmic_core.c

> +
> +/* Set the required voltage level of pmic
> + *
> + * @param reg		register number of buck/ldo to be set
> + * @param volt		voltage level to be set
> + * @param enable	enable or disable bit
> + *
> + * @return		Return 0 if ok, else -1
> + */
> +static int max77686_volsetting(enum max77686_regnum reg, unsigned
> int volt,
> +			       int enable)
> +{
> +	struct max77686_para *pmic;
> +	unsigned char read_data;
> +	unsigned int vol_level = 0;
> +	int ret;
> +
> +	pmic = &max77686_param[reg];
> +
> +	if (pmic->vol_addr == 0) {
> +		debug("not a voltage register.\n");
> +		return -1;
> +	}
> +
> +	ret = max77686_i2c_read(MAX77686_I2C_ADDR, pmic->vol_addr,
> &read_data);
> +	if (ret != 0) {
> +		debug("max77686 i2c read failed.\n");
> +		return -1;
> +	}
> +
> +	if (volt - pmic->vol_min > 0)
> +		vol_level = ((volt - pmic->vol_min) * 1000) /
> pmic->vol_div; +
> +	clrsetbits_8(&read_data, pmic->vol_bitmask <<
> pmic->vol_bitpos,
> +			vol_level << pmic->vol_bitpos);
> +
> +	ret = max77686_i2c_write(MAX77686_I2C_ADDR, pmic->vol_addr,
> read_data);
> +	if (ret != 0) {
> +		debug("max77686 i2c write failed.\n");
> +		return -1;
> +	}
> +
> +	ret = max77686_enablereg(reg, enable);
> +	if (ret != 0) {
> +		debug("Failed to enable buck/ldo.\n");
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +

I believe,that it would be better to further develop PMIC
framework, than writing your own "special" driver.


> +int max77686_enable_32khz_cp(void)
> +{
> +	return max77686_enablereg(PMIC_EN32KHZ_CP, REG_ENABLE);
> +}
> +
> +/**
> + * Initialize the pmic voltages to power up the system
> + * This also calls i2c_init so that we can program the pmic
> + *
> + * REG_ENABLE = 0, needed to set the buck/ldo enable bit ON
> + *
> + * @return	Return 0 if ok, else -1
> + */
> +int power_init(void)
> +{
> +	int error = 0;
> +
> +	/* init the i2c so that we can program pmic chip */
> +	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
> +
> +	error = max77686_volsetting(PMIC_BUCK2, CONFIG_VDD_ARM,
> REG_ENABLE);
> +	error |= max77686_volsetting(PMIC_BUCK3, CONFIG_VDD_INT,
> REG_ENABLE);
> +	error |= max77686_volsetting(PMIC_BUCK1, CONFIG_VDD_MIF,
> REG_ENABLE);
> +	error |= max77686_volsetting(PMIC_LDO2, CONFIG_VDD_LDO2,
> REG_ENABLE);
> +	error |= max77686_volsetting(PMIC_LDO3, CONFIG_VDD_LDO3,
> REG_ENABLE);
> +	error |= max77686_volsetting(PMIC_LDO5, CONFIG_VDD_LDO5,
> REG_ENABLE);
> +	error |= max77686_volsetting(PMIC_LDO10, CONFIG_VDD_LDO10,
> REG_ENABLE);
> +	if (error != 0)
> +		debug("power init failed\n");
> +
> +	return error;
> +}
> diff --git a/include/max77686.h b/include/max77686.h
> new file mode 100644
> index 0000000..e630ed8
> --- /dev/null
> +++ b/include/max77686.h
> @@ -0,0 +1,115 @@
> +/*
> + *  Copyright (C) 2012 Samsung Electronics
> + *  Alim Akhtar <alim.akhtar@samsung.com>
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License as
> + * published by the Free Software Foundation; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +#ifndef __MAX77686_H_
> +#define __MAX77686_H_
> +
> +enum max77686_regnum {
> +	PMIC_BUCK1 = 0,
> +	PMIC_BUCK2,
> +	PMIC_BUCK3,
> +	PMIC_BUCK4,
> +	PMIC_BUCK5,
> +	PMIC_BUCK6,
> +	PMIC_BUCK7,
> +	PMIC_BUCK8,
> +	PMIC_BUCK9,
> +	PMIC_LDO1,
> +	PMIC_LDO2,
> +	PMIC_LDO3,
> +	PMIC_LDO4,
> +	PMIC_LDO5,
> +	PMIC_LDO6,
> +	PMIC_LDO7,
> +	PMIC_LDO8,
> +	PMIC_LDO9,
> +	PMIC_LDO10,
> +	PMIC_LDO11,
> +	PMIC_LDO12,
> +	PMIC_LDO13,
> +	PMIC_LDO14,
> +	PMIC_LDO15,
> +	PMIC_LDO16,
> +	PMIC_LDO17,
> +	PMIC_LDO18,
> +	PMIC_LDO19,
> +	PMIC_LDO20,
> +	PMIC_LDO21,
> +	PMIC_LDO22,
> +	PMIC_LDO23,
> +	PMIC_LDO24,
> +	PMIC_LDO25,
> +	PMIC_LDO26,
> +	PMIC_EN32KHZ_CP
> +};
> +
> +/**
> + * struct max77686_para - max77686 register parameters
> + * @param vol_addr	i2c address of the given buck/ldo register
> + * @param vol_bitpos	bit position to be set or clear within
> register
> + * @param vol_bitmask	bit mask value
> + * @param reg_enaddr	control register address, which enable
> the given
> + *			given buck/ldo.
> + * @param reg_enbitpos	bit position to be enabled
> + * @param reg_enbiton	value to be written to buck/ldo to make
> it ON
> + * @param reg_enbitoff	value to be written to buck/ldo to
> make it OFF
> + * @param vol_min	minimum voltage level supported by given
> buck/ldo
> + * @param vol_div	voltage division value of given buck/ldo
> + */
> +struct max77686_para {
> +	enum max77686_regnum regnum;
> +	u8	vol_addr;
> +	u8	vol_bitpos;
> +	u8	vol_bitmask;
> +	u8	reg_enaddr;
> +	u8	reg_enbitpos;
> +	u8	reg_enbitmask;
> +	u8	reg_enbiton;
> +	u8	reg_enbitoff;
> +	u32	vol_min;
> +	u32	vol_div;
> +};
> +
> +/* I2C device address for pmic max77686 */
> +#define MAX77686_I2C_ADDR (0x12 >> 1)
> +
> +enum {
> +	REG_DISABLE = 0,
> +	REG_ENABLE
> +};
> +
> +/**
> + * This function enables the 32KHz coprocessor clock.
> + *
> + * Return 0 if ok, else -1
> + */
> +int max77686_enable_32khz_cp(void);
> +
> +/**
> + * This function sets the BUCK's/LDO's voltages of pmic
> + *
> + * Return 0 if ok, else -1
> + */
> +int power_init(void);
> +
> +#endif /* __MAX77686_PMIC_H_ */

It looks like the max77686.h file is already written in a similar way
to e.g. max8998.h file and stick to the PMIC framework.

I'd really encourage you to look into the PMIC driver and adjust your
driver to the PMIC framework.
Rajeshwari Birje May 23, 2012, 5:27 a.m. | #2
Hi Lukasz Majewski,

Thank you for the coments.

On Tue, May 22, 2012 at 12:20 PM, Lukasz Majewski
<l.majewski@samsung.com> wrote:
> Hi Rajeshwari,
>
>> This patch adds driver and register definitions for PMIC chip
>> MAX77686.
>
> Why don't use the PMIC framework? Please look into drivers/misc/pmic_*
> for examples.
Will implement the same and resend the patch.
>
> For now there is a support for MAX899{7|8} chips for Samsung platforms.
>
>>
>> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
>> Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
>> ---
>>  drivers/power/Makefile   |    1 +
>>  drivers/power/max77686.c |  225
>> ++++++++++++++++++++++++++++++++++++++++++++++
>> include/max77686.h       |  115 +++++++++++++++++++++++ 3 files
>> changed, 341 insertions(+), 0 deletions(-) create mode 100644
>> drivers/power/max77686.c create mode 100644 include/max77686.h
>>
>> diff --git a/drivers/power/Makefile b/drivers/power/Makefile
>> index 6bf388c..b4ffc1d 100644
>> --- a/drivers/power/Makefile
>> +++ b/drivers/power/Makefile
>> @@ -26,6 +26,7 @@ include $(TOPDIR)/config.mk
>>  LIB  := $(obj)libpower.o
>>
>>  COBJS-$(CONFIG_FTPMU010_POWER)       += ftpmu010.o
>> +COBJS-$(CONFIG_MAX77686_POWER)       += max77686.o
>>  COBJS-$(CONFIG_TPS6586X_POWER)       += tps6586x.o
>>  COBJS-$(CONFIG_TWL4030_POWER)        += twl4030.o
>>  COBJS-$(CONFIG_TWL6030_POWER)        += twl6030.o
>> diff --git a/drivers/power/max77686.c b/drivers/power/max77686.c
>> new file mode 100644
>> index 0000000..cf58611
>> --- /dev/null
>> +++ b/drivers/power/max77686.c
>> @@ -0,0 +1,225 @@
>> +/*
>> + * Copyright (C) 2012 Samsung Electronics
>> + * Alim Akhtar <alim.akhtar@samsung.com>
>> + *
>> + * See file CREDITS for list of people who contributed to this
>> + * project.
>> + *
>> + * This program is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU General Public License as
>> + * published by the Free Software Foundation; either version 2 of
>> + * the License, or (at your option) any later version.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> + * GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program; if not, write to the Free Software
>> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
>> + * MA 02111-1307 USA
>> + */
>> +
>> +#include <common.h>
>> +#include <i2c.h>
>> +#include <max77686.h>
>> +
>> +/*
>> + * Max77686 parameters values
>> + * see max77686.h for parameters details
>> + */
>> +struct max77686_para max77686_param[] = {/*{regnum, vol_addr,
>> vol_bitpos,
>> +     vol_bitmask, reg_enaddr, reg_enbitpos, reg_enbitmask,
>> reg_enbiton,
>> +     reg_enbitoff, vol_min, vol_div}*/
>> +     {PMIC_BUCK1, 0x11, 0x0, 0x3F, 0x10, 0x0, 0x3, 0x3, 0x0, 750,
>> 50000},
>> +     {PMIC_BUCK2, 0x14, 0x0, 0xFF, 0x12, 0x4, 0x3, 0x1, 0x0, 600,
>> 12500},
>> +     {PMIC_BUCK3, 0x1E, 0x0, 0xFF, 0x1C, 0x4, 0x3, 0x1, 0x0, 600,
>> 12500},
>> +     {PMIC_BUCK4, 0x28, 0x0, 0xFF, 0x26, 0x4, 0x3, 0x1, 0x0, 600,
>> 12500},
>> +     {PMIC_BUCK5, 0x31, 0x0, 0x3F, 0x30, 0x0, 0x3, 0x3, 0x0, 750,
>> 50000},
>> +     {PMIC_BUCK6, 0x33, 0x0, 0x3F, 0x32, 0x0, 0x3, 0x3, 0x0, 750,
>> 50000},
>> +     {PMIC_BUCK7, 0x35, 0x0, 0x3F, 0x34, 0x0, 0x3, 0x3, 0x0, 750,
>> 50000},
>> +     {PMIC_BUCK8, 0x37, 0x0, 0x3F, 0x36, 0x0, 0x3, 0x3, 0x0, 750,
>> 50000},
>> +     {PMIC_BUCK9, 0x39, 0x0, 0x3F, 0x38, 0x0, 0x3, 0x3, 0x0, 750,
>> 50000},
>> +     {PMIC_LDO1,  0x40, 0x0, 0x3F, 0x40, 0x6, 0x3, 0x3, 0x0, 800,
>> 25000},
>> +     {PMIC_LDO2,  0x41, 0x0, 0x3F, 0x41, 0x6, 0x3, 0x1, 0x0, 800,
>> 25000},
>> +     {PMIC_LDO3,  0x42, 0x0, 0x3F, 0x42, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO4,  0x43, 0x0, 0x3F, 0x43, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO5,  0x44, 0x0, 0x3F, 0x44, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO6,  0x45, 0x0, 0x3F, 0x45, 0x6, 0x3, 0x1, 0x0, 800,
>> 25000},
>> +     {PMIC_LDO7,  0x46, 0x0, 0x3F, 0x46, 0x6, 0x3, 0x1, 0x0, 800,
>> 25000},
>> +     {PMIC_LDO8,  0x47, 0x0, 0x3F, 0x47, 0x6, 0x3, 0x1, 0x0, 800,
>> 25000},
>> +     {PMIC_LDO9,  0x48, 0x0, 0x3F, 0x48, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO10, 0x49, 0x0, 0x3F, 0x49, 0x6, 0x3, 0x1, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO11, 0x4A, 0x0, 0x3F, 0x4A, 0x6, 0x3, 0x1, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO12, 0x4B, 0x0, 0x3F, 0x4B, 0x6, 0x3, 0x1, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO13, 0x4C, 0x0, 0x3F, 0x4C, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO14, 0x4D, 0x0, 0x3F, 0x4D, 0x6, 0x3, 0x1, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO15, 0x4E, 0x0, 0x3F, 0x4E, 0x6, 0x3, 0x1, 0x0, 800,
>> 25000},
>> +     {PMIC_LDO16, 0x4F, 0x0, 0x3F, 0x4F, 0x6, 0x3, 0x1, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO17, 0x50, 0x0, 0x3F, 0x50, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO18, 0x51, 0x0, 0x3F, 0x51, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO19, 0x52, 0x0, 0x3F, 0x52, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO20, 0x53, 0x0, 0x3F, 0x53, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO21, 0x54, 0x0, 0x3F, 0x54, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO22, 0x55, 0x0, 0x3F, 0x55, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO23, 0x56, 0x0, 0x3F, 0x56, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO24, 0x57, 0x0, 0x3F, 0x57, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO25, 0x58, 0x0, 0x3F, 0x58, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_LDO26, 0x59, 0x0, 0x3F, 0x59, 0x6, 0x3, 0x3, 0x0, 800,
>> 50000},
>> +     {PMIC_EN32KHZ_CP, 0x0, 0x0, 0x0, 0x7F, 0x1, 0x1, 0x1, 0x0,
>> 0x0, 0x0}, +};
>
> Frankly speaking it looks a bit unreadable (especially without specs
> attached).
>
- ok
>> +
>> +/*
>> + * Write a value to a register
>> + *
>> + * @param chip_addr  i2c addr for max77686
>> + * @param reg                reg number to write
>> + * @param val                value to be written
>> + *
>> + */
>> +static inline int max77686_i2c_write(unsigned char chip_addr,
>> +                                     unsigned int reg, unsigned
>> char val) +{
>> +     return i2c_write(chip_addr, reg, 1, &val, 1);
>> +}
>
> This "write register" is also available in the PMIC framework.
- will reuse the same.
>
>> +
>> +/*
>> + * Read a value from a register
>> + *
>> + * @param chip_addr  i2c addr for max77686
>> + * @param reg                reg number to write
>> + * @param val                value to be written
>> + *
>> + */
>> +static inline int max77686_i2c_read(unsigned char chip_addr,
>> +                                     unsigned int reg, unsigned
>
> It is also available on the PMIC framework.
>
>> char *val) +{
>> +     return i2c_read(chip_addr, reg, 1, val, 1);
>> +}
>> +
>> +/*
>> + * Enable the max77686 register
>> + *
>> + * @param reg                register number of buck/ldo to be
>> enabled
>> + * @param enable     enable or disable bit
>> + *
>> + *                   REG_DISABLE = 0,
>> +                     needed to set the buck/ldo enable bit OFF
>> + * @return           Return 0 if ok, else -1
>> + */
>> +static int max77686_enablereg(enum max77686_regnum reg, int enable)
>> +{
>> +     struct max77686_para *pmic;
>> +     unsigned char read_data;
>> +     int ret;
>> +
>> +     pmic = &max77686_param[reg];
>> +
>> +     ret = max77686_i2c_read(MAX77686_I2C_ADDR, pmic->vol_addr,
>> &read_data);
>> +     if (ret != 0) {
>> +             debug("max77686 i2c read failed.\n");
>> +             return -1;
>> +     }
>> +
>> +     if (enable == REG_DISABLE) {
>> +             clrbits_8(&read_data,
>> +                             pmic->reg_enbitmask <<
>> pmic->reg_enbitpos);
>> +     } else {
>> +             clrsetbits_8(&read_data,
>> +                             pmic->reg_enbitmask <<
>> pmic->reg_enbitpos,
>> +                             pmic->reg_enbiton <<
>> pmic->reg_enbitpos);
>> +     }
>> +
>> +     ret = max77686_i2c_write(MAX77686_I2C_ADDR,
>> +                              pmic->reg_enaddr, read_data);
>> +     if (ret != 0) {
>> +             debug("max77686 i2c write failed.\n");
>> +             return -1;
>> +     }
>> +
>> +     return 0;
>> +}
>
> Please look into the PMIC section of ./board/samsung/trats/trats.c for
> reference. Moreover changing/enabling regulator function is already
> available at pmic_core.c
- Ok
>
>> +
>> +/* Set the required voltage level of pmic
>> + *
>> + * @param reg                register number of buck/ldo to be set
>> + * @param volt               voltage level to be set
>> + * @param enable     enable or disable bit
>> + *
>> + * @return           Return 0 if ok, else -1
>> + */
>> +static int max77686_volsetting(enum max77686_regnum reg, unsigned
>> int volt,
>> +                            int enable)
>> +{
>> +     struct max77686_para *pmic;
>> +     unsigned char read_data;
>> +     unsigned int vol_level = 0;
>> +     int ret;
>> +
>> +     pmic = &max77686_param[reg];
>> +
>> +     if (pmic->vol_addr == 0) {
>> +             debug("not a voltage register.\n");
>> +             return -1;
>> +     }
>> +
>> +     ret = max77686_i2c_read(MAX77686_I2C_ADDR, pmic->vol_addr,
>> &read_data);
>> +     if (ret != 0) {
>> +             debug("max77686 i2c read failed.\n");
>> +             return -1;
>> +     }
>> +
>> +     if (volt - pmic->vol_min > 0)
>> +             vol_level = ((volt - pmic->vol_min) * 1000) /
>> pmic->vol_div; +
>> +     clrsetbits_8(&read_data, pmic->vol_bitmask <<
>> pmic->vol_bitpos,
>> +                     vol_level << pmic->vol_bitpos);
>> +
>> +     ret = max77686_i2c_write(MAX77686_I2C_ADDR, pmic->vol_addr,
>> read_data);
>> +     if (ret != 0) {
>> +             debug("max77686 i2c write failed.\n");
>> +             return -1;
>> +     }
>> +
>> +     ret = max77686_enablereg(reg, enable);
>> +     if (ret != 0) {
>> +             debug("Failed to enable buck/ldo.\n");
>> +             return -1;
>> +     }
>> +
>> +     return 0;
>> +}
>> +
>
> I believe,that it would be better to further develop PMIC
> framework, than writing your own "special" driver.
Will rework on the same.
>
>
>> +int max77686_enable_32khz_cp(void)
>> +{
>> +     return max77686_enablereg(PMIC_EN32KHZ_CP, REG_ENABLE);
>> +}
>> +
>> +/**
>> + * Initialize the pmic voltages to power up the system
>> + * This also calls i2c_init so that we can program the pmic
>> + *
>> + * REG_ENABLE = 0, needed to set the buck/ldo enable bit ON
>> + *
>> + * @return   Return 0 if ok, else -1
>> + */
>> +int power_init(void)
>> +{
>> +     int error = 0;
>> +
>> +     /* init the i2c so that we can program pmic chip */
>> +     i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
>> +
>> +     error = max77686_volsetting(PMIC_BUCK2, CONFIG_VDD_ARM,
>> REG_ENABLE);
>> +     error |= max77686_volsetting(PMIC_BUCK3, CONFIG_VDD_INT,
>> REG_ENABLE);
>> +     error |= max77686_volsetting(PMIC_BUCK1, CONFIG_VDD_MIF,
>> REG_ENABLE);
>> +     error |= max77686_volsetting(PMIC_LDO2, CONFIG_VDD_LDO2,
>> REG_ENABLE);
>> +     error |= max77686_volsetting(PMIC_LDO3, CONFIG_VDD_LDO3,
>> REG_ENABLE);
>> +     error |= max77686_volsetting(PMIC_LDO5, CONFIG_VDD_LDO5,
>> REG_ENABLE);
>> +     error |= max77686_volsetting(PMIC_LDO10, CONFIG_VDD_LDO10,
>> REG_ENABLE);
>> +     if (error != 0)
>> +             debug("power init failed\n");
>> +
>> +     return error;
>> +}
>> diff --git a/include/max77686.h b/include/max77686.h
>> new file mode 100644
>> index 0000000..e630ed8
>> --- /dev/null
>> +++ b/include/max77686.h
>> @@ -0,0 +1,115 @@
>> +/*
>> + *  Copyright (C) 2012 Samsung Electronics
>> + *  Alim Akhtar <alim.akhtar@samsung.com>
>> + *
>> + * See file CREDITS for list of people who contributed to this
>> + * project.
>> + *
>> + * This program is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU General Public License as
>> + * published by the Free Software Foundation; either version 2 of
>> + * the License, or (at your option) any later version.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program; if not, write to the Free Software
>> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
>> + * MA 02111-1307 USA
>> + */
>> +
>> +#ifndef __MAX77686_H_
>> +#define __MAX77686_H_
>> +
>> +enum max77686_regnum {
>> +     PMIC_BUCK1 = 0,
>> +     PMIC_BUCK2,
>> +     PMIC_BUCK3,
>> +     PMIC_BUCK4,
>> +     PMIC_BUCK5,
>> +     PMIC_BUCK6,
>> +     PMIC_BUCK7,
>> +     PMIC_BUCK8,
>> +     PMIC_BUCK9,
>> +     PMIC_LDO1,
>> +     PMIC_LDO2,
>> +     PMIC_LDO3,
>> +     PMIC_LDO4,
>> +     PMIC_LDO5,
>> +     PMIC_LDO6,
>> +     PMIC_LDO7,
>> +     PMIC_LDO8,
>> +     PMIC_LDO9,
>> +     PMIC_LDO10,
>> +     PMIC_LDO11,
>> +     PMIC_LDO12,
>> +     PMIC_LDO13,
>> +     PMIC_LDO14,
>> +     PMIC_LDO15,
>> +     PMIC_LDO16,
>> +     PMIC_LDO17,
>> +     PMIC_LDO18,
>> +     PMIC_LDO19,
>> +     PMIC_LDO20,
>> +     PMIC_LDO21,
>> +     PMIC_LDO22,
>> +     PMIC_LDO23,
>> +     PMIC_LDO24,
>> +     PMIC_LDO25,
>> +     PMIC_LDO26,
>> +     PMIC_EN32KHZ_CP
>> +};
>> +
>> +/**
>> + * struct max77686_para - max77686 register parameters
>> + * @param vol_addr   i2c address of the given buck/ldo register
>> + * @param vol_bitpos bit position to be set or clear within
>> register
>> + * @param vol_bitmask        bit mask value
>> + * @param reg_enaddr control register address, which enable
>> the given
>> + *                   given buck/ldo.
>> + * @param reg_enbitpos       bit position to be enabled
>> + * @param reg_enbiton        value to be written to buck/ldo to make
>> it ON
>> + * @param reg_enbitoff       value to be written to buck/ldo to
>> make it OFF
>> + * @param vol_min    minimum voltage level supported by given
>> buck/ldo
>> + * @param vol_div    voltage division value of given buck/ldo
>> + */
>> +struct max77686_para {
>> +     enum max77686_regnum regnum;
>> +     u8      vol_addr;
>> +     u8      vol_bitpos;
>> +     u8      vol_bitmask;
>> +     u8      reg_enaddr;
>> +     u8      reg_enbitpos;
>> +     u8      reg_enbitmask;
>> +     u8      reg_enbiton;
>> +     u8      reg_enbitoff;
>> +     u32     vol_min;
>> +     u32     vol_div;
>> +};
>> +
>> +/* I2C device address for pmic max77686 */
>> +#define MAX77686_I2C_ADDR (0x12 >> 1)
>> +
>> +enum {
>> +     REG_DISABLE = 0,
>> +     REG_ENABLE
>> +};
>> +
>> +/**
>> + * This function enables the 32KHz coprocessor clock.
>> + *
>> + * Return 0 if ok, else -1
>> + */
>> +int max77686_enable_32khz_cp(void);
>> +
>> +/**
>> + * This function sets the BUCK's/LDO's voltages of pmic
>> + *
>> + * Return 0 if ok, else -1
>> + */
>> +int power_init(void);
>> +
>> +#endif /* __MAX77686_PMIC_H_ */
>
> It looks like the max77686.h file is already written in a similar way
> to e.g. max8998.h file and stick to the PMIC framework.
>
> I'd really encourage you to look into the PMIC driver and adjust your
> driver to the PMIC framework.
>
> --
> Best regards,
>
> Lukasz Majewski
>
> Samsung Poland R&D Center | Linux Platform Group
> _______________________________________________
> U-Boot mailing list
> U-Boot@lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot

Regards
Rajeshwari Shinde.

Patch

diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index 6bf388c..b4ffc1d 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -26,6 +26,7 @@  include $(TOPDIR)/config.mk
 LIB 	:= $(obj)libpower.o
 
 COBJS-$(CONFIG_FTPMU010_POWER)	+= ftpmu010.o
+COBJS-$(CONFIG_MAX77686_POWER)	+= max77686.o
 COBJS-$(CONFIG_TPS6586X_POWER)	+= tps6586x.o
 COBJS-$(CONFIG_TWL4030_POWER)	+= twl4030.o
 COBJS-$(CONFIG_TWL6030_POWER)	+= twl6030.o
diff --git a/drivers/power/max77686.c b/drivers/power/max77686.c
new file mode 100644
index 0000000..cf58611
--- /dev/null
+++ b/drivers/power/max77686.c
@@ -0,0 +1,225 @@ 
+/*
+ * Copyright (C) 2012 Samsung Electronics
+ * Alim Akhtar <alim.akhtar@samsung.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <max77686.h>
+
+/*
+ * Max77686 parameters values
+ * see max77686.h for parameters details
+ */
+struct max77686_para max77686_param[] = {/*{regnum, vol_addr, vol_bitpos,
+	vol_bitmask, reg_enaddr, reg_enbitpos, reg_enbitmask, reg_enbiton,
+	reg_enbitoff, vol_min, vol_div}*/
+	{PMIC_BUCK1, 0x11, 0x0, 0x3F, 0x10, 0x0, 0x3, 0x3, 0x0, 750, 50000},
+	{PMIC_BUCK2, 0x14, 0x0, 0xFF, 0x12, 0x4, 0x3, 0x1, 0x0, 600, 12500},
+	{PMIC_BUCK3, 0x1E, 0x0, 0xFF, 0x1C, 0x4, 0x3, 0x1, 0x0, 600, 12500},
+	{PMIC_BUCK4, 0x28, 0x0, 0xFF, 0x26, 0x4, 0x3, 0x1, 0x0, 600, 12500},
+	{PMIC_BUCK5, 0x31, 0x0, 0x3F, 0x30, 0x0, 0x3, 0x3, 0x0, 750, 50000},
+	{PMIC_BUCK6, 0x33, 0x0, 0x3F, 0x32, 0x0, 0x3, 0x3, 0x0, 750, 50000},
+	{PMIC_BUCK7, 0x35, 0x0, 0x3F, 0x34, 0x0, 0x3, 0x3, 0x0, 750, 50000},
+	{PMIC_BUCK8, 0x37, 0x0, 0x3F, 0x36, 0x0, 0x3, 0x3, 0x0, 750, 50000},
+	{PMIC_BUCK9, 0x39, 0x0, 0x3F, 0x38, 0x0, 0x3, 0x3, 0x0, 750, 50000},
+	{PMIC_LDO1,  0x40, 0x0, 0x3F, 0x40, 0x6, 0x3, 0x3, 0x0, 800, 25000},
+	{PMIC_LDO2,  0x41, 0x0, 0x3F, 0x41, 0x6, 0x3, 0x1, 0x0, 800, 25000},
+	{PMIC_LDO3,  0x42, 0x0, 0x3F, 0x42, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO4,  0x43, 0x0, 0x3F, 0x43, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO5,  0x44, 0x0, 0x3F, 0x44, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO6,  0x45, 0x0, 0x3F, 0x45, 0x6, 0x3, 0x1, 0x0, 800, 25000},
+	{PMIC_LDO7,  0x46, 0x0, 0x3F, 0x46, 0x6, 0x3, 0x1, 0x0, 800, 25000},
+	{PMIC_LDO8,  0x47, 0x0, 0x3F, 0x47, 0x6, 0x3, 0x1, 0x0, 800, 25000},
+	{PMIC_LDO9,  0x48, 0x0, 0x3F, 0x48, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO10, 0x49, 0x0, 0x3F, 0x49, 0x6, 0x3, 0x1, 0x0, 800, 50000},
+	{PMIC_LDO11, 0x4A, 0x0, 0x3F, 0x4A, 0x6, 0x3, 0x1, 0x0, 800, 50000},
+	{PMIC_LDO12, 0x4B, 0x0, 0x3F, 0x4B, 0x6, 0x3, 0x1, 0x0, 800, 50000},
+	{PMIC_LDO13, 0x4C, 0x0, 0x3F, 0x4C, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO14, 0x4D, 0x0, 0x3F, 0x4D, 0x6, 0x3, 0x1, 0x0, 800, 50000},
+	{PMIC_LDO15, 0x4E, 0x0, 0x3F, 0x4E, 0x6, 0x3, 0x1, 0x0, 800, 25000},
+	{PMIC_LDO16, 0x4F, 0x0, 0x3F, 0x4F, 0x6, 0x3, 0x1, 0x0, 800, 50000},
+	{PMIC_LDO17, 0x50, 0x0, 0x3F, 0x50, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO18, 0x51, 0x0, 0x3F, 0x51, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO19, 0x52, 0x0, 0x3F, 0x52, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO20, 0x53, 0x0, 0x3F, 0x53, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO21, 0x54, 0x0, 0x3F, 0x54, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO22, 0x55, 0x0, 0x3F, 0x55, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO23, 0x56, 0x0, 0x3F, 0x56, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO24, 0x57, 0x0, 0x3F, 0x57, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO25, 0x58, 0x0, 0x3F, 0x58, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_LDO26, 0x59, 0x0, 0x3F, 0x59, 0x6, 0x3, 0x3, 0x0, 800, 50000},
+	{PMIC_EN32KHZ_CP, 0x0, 0x0, 0x0, 0x7F, 0x1, 0x1, 0x1, 0x0, 0x0, 0x0},
+};
+
+/*
+ * Write a value to a register
+ *
+ * @param chip_addr	i2c addr for max77686
+ * @param reg		reg number to write
+ * @param val		value to be written
+ *
+ */
+static inline int max77686_i2c_write(unsigned char chip_addr,
+					unsigned int reg, unsigned char val)
+{
+	return i2c_write(chip_addr, reg, 1, &val, 1);
+}
+
+/*
+ * Read a value from a register
+ *
+ * @param chip_addr	i2c addr for max77686
+ * @param reg		reg number to write
+ * @param val		value to be written
+ *
+ */
+static inline int max77686_i2c_read(unsigned char chip_addr,
+					unsigned int reg, unsigned char *val)
+{
+	return i2c_read(chip_addr, reg, 1, val, 1);
+}
+
+/*
+ * Enable the max77686 register
+ *
+ * @param reg		register number of buck/ldo to be enabled
+ * @param enable	enable or disable bit
+ *
+ *			REG_DISABLE = 0,
+			needed to set the buck/ldo enable bit OFF
+ * @return		Return 0 if ok, else -1
+ */
+static int max77686_enablereg(enum max77686_regnum reg, int enable)
+{
+	struct max77686_para *pmic;
+	unsigned char read_data;
+	int ret;
+
+	pmic = &max77686_param[reg];
+
+	ret = max77686_i2c_read(MAX77686_I2C_ADDR, pmic->vol_addr, &read_data);
+	if (ret != 0) {
+		debug("max77686 i2c read failed.\n");
+		return -1;
+	}
+
+	if (enable == REG_DISABLE) {
+		clrbits_8(&read_data,
+				pmic->reg_enbitmask << pmic->reg_enbitpos);
+	} else {
+		clrsetbits_8(&read_data,
+				pmic->reg_enbitmask << pmic->reg_enbitpos,
+				pmic->reg_enbiton << pmic->reg_enbitpos);
+	}
+
+	ret = max77686_i2c_write(MAX77686_I2C_ADDR,
+				 pmic->reg_enaddr, read_data);
+	if (ret != 0) {
+		debug("max77686 i2c write failed.\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+/* Set the required voltage level of pmic
+ *
+ * @param reg		register number of buck/ldo to be set
+ * @param volt		voltage level to be set
+ * @param enable	enable or disable bit
+ *
+ * @return		Return 0 if ok, else -1
+ */
+static int max77686_volsetting(enum max77686_regnum reg, unsigned int volt,
+			       int enable)
+{
+	struct max77686_para *pmic;
+	unsigned char read_data;
+	unsigned int vol_level = 0;
+	int ret;
+
+	pmic = &max77686_param[reg];
+
+	if (pmic->vol_addr == 0) {
+		debug("not a voltage register.\n");
+		return -1;
+	}
+
+	ret = max77686_i2c_read(MAX77686_I2C_ADDR, pmic->vol_addr, &read_data);
+	if (ret != 0) {
+		debug("max77686 i2c read failed.\n");
+		return -1;
+	}
+
+	if (volt - pmic->vol_min > 0)
+		vol_level = ((volt - pmic->vol_min) * 1000) / pmic->vol_div;
+
+	clrsetbits_8(&read_data, pmic->vol_bitmask << pmic->vol_bitpos,
+			vol_level << pmic->vol_bitpos);
+
+	ret = max77686_i2c_write(MAX77686_I2C_ADDR, pmic->vol_addr, read_data);
+	if (ret != 0) {
+		debug("max77686 i2c write failed.\n");
+		return -1;
+	}
+
+	ret = max77686_enablereg(reg, enable);
+	if (ret != 0) {
+		debug("Failed to enable buck/ldo.\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+int max77686_enable_32khz_cp(void)
+{
+	return max77686_enablereg(PMIC_EN32KHZ_CP, REG_ENABLE);
+}
+
+/**
+ * Initialize the pmic voltages to power up the system
+ * This also calls i2c_init so that we can program the pmic
+ *
+ * REG_ENABLE = 0, needed to set the buck/ldo enable bit ON
+ *
+ * @return	Return 0 if ok, else -1
+ */
+int power_init(void)
+{
+	int error = 0;
+
+	/* init the i2c so that we can program pmic chip */
+	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+
+	error = max77686_volsetting(PMIC_BUCK2, CONFIG_VDD_ARM, REG_ENABLE);
+	error |= max77686_volsetting(PMIC_BUCK3, CONFIG_VDD_INT, REG_ENABLE);
+	error |= max77686_volsetting(PMIC_BUCK1, CONFIG_VDD_MIF, REG_ENABLE);
+	error |= max77686_volsetting(PMIC_LDO2, CONFIG_VDD_LDO2, REG_ENABLE);
+	error |= max77686_volsetting(PMIC_LDO3, CONFIG_VDD_LDO3, REG_ENABLE);
+	error |= max77686_volsetting(PMIC_LDO5, CONFIG_VDD_LDO5, REG_ENABLE);
+	error |= max77686_volsetting(PMIC_LDO10, CONFIG_VDD_LDO10, REG_ENABLE);
+	if (error != 0)
+		debug("power init failed\n");
+
+	return error;
+}
diff --git a/include/max77686.h b/include/max77686.h
new file mode 100644
index 0000000..e630ed8
--- /dev/null
+++ b/include/max77686.h
@@ -0,0 +1,115 @@ 
+/*
+ *  Copyright (C) 2012 Samsung Electronics
+ *  Alim Akhtar <alim.akhtar@samsung.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef __MAX77686_H_
+#define __MAX77686_H_
+
+enum max77686_regnum {
+	PMIC_BUCK1 = 0,
+	PMIC_BUCK2,
+	PMIC_BUCK3,
+	PMIC_BUCK4,
+	PMIC_BUCK5,
+	PMIC_BUCK6,
+	PMIC_BUCK7,
+	PMIC_BUCK8,
+	PMIC_BUCK9,
+	PMIC_LDO1,
+	PMIC_LDO2,
+	PMIC_LDO3,
+	PMIC_LDO4,
+	PMIC_LDO5,
+	PMIC_LDO6,
+	PMIC_LDO7,
+	PMIC_LDO8,
+	PMIC_LDO9,
+	PMIC_LDO10,
+	PMIC_LDO11,
+	PMIC_LDO12,
+	PMIC_LDO13,
+	PMIC_LDO14,
+	PMIC_LDO15,
+	PMIC_LDO16,
+	PMIC_LDO17,
+	PMIC_LDO18,
+	PMIC_LDO19,
+	PMIC_LDO20,
+	PMIC_LDO21,
+	PMIC_LDO22,
+	PMIC_LDO23,
+	PMIC_LDO24,
+	PMIC_LDO25,
+	PMIC_LDO26,
+	PMIC_EN32KHZ_CP
+};
+
+/**
+ * struct max77686_para - max77686 register parameters
+ * @param vol_addr	i2c address of the given buck/ldo register
+ * @param vol_bitpos	bit position to be set or clear within register
+ * @param vol_bitmask	bit mask value
+ * @param reg_enaddr	control register address, which enable the given
+ *			given buck/ldo.
+ * @param reg_enbitpos	bit position to be enabled
+ * @param reg_enbiton	value to be written to buck/ldo to make it ON
+ * @param reg_enbitoff	value to be written to buck/ldo to make it OFF
+ * @param vol_min	minimum voltage level supported by given buck/ldo
+ * @param vol_div	voltage division value of given buck/ldo
+ */
+struct max77686_para {
+	enum max77686_regnum regnum;
+	u8	vol_addr;
+	u8	vol_bitpos;
+	u8	vol_bitmask;
+	u8	reg_enaddr;
+	u8	reg_enbitpos;
+	u8	reg_enbitmask;
+	u8	reg_enbiton;
+	u8	reg_enbitoff;
+	u32	vol_min;
+	u32	vol_div;
+};
+
+/* I2C device address for pmic max77686 */
+#define MAX77686_I2C_ADDR (0x12 >> 1)
+
+enum {
+	REG_DISABLE = 0,
+	REG_ENABLE
+};
+
+/**
+ * This function enables the 32KHz coprocessor clock.
+ *
+ * Return 0 if ok, else -1
+ */
+int max77686_enable_32khz_cp(void);
+
+/**
+ * This function sets the BUCK's/LDO's voltages of pmic
+ *
+ * Return 0 if ok, else -1
+ */
+int power_init(void);
+
+#endif /* __MAX77686_PMIC_H_ */