diff mbox

[5/6,V2] I2C: Driver changes for FDT support

Message ID 1352884279-24067-6-git-send-email-rajeshwari.s@samsung.com
State New
Headers show

Commit Message

Rajeshwari Shinde Nov. 14, 2012, 9:11 a.m. UTC 
Functions added to get the I2C bus number and reset I2C bus using
FDT node.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
---
Changes in V2:
	- Added periph id to I2C bus structure.
	- Modified i2c_get_bus_num_fdt function to compare with node.
	- Board i2c init moved to driver in case of FDT.
 drivers/i2c/s3c24x0_i2c.c |   90 ++++++++++++++++++++++++++++++++++++++++++++-
 drivers/i2c/s3c24x0_i2c.h |    8 ++++
 include/i2c.h             |   26 +++++++++++++
 3 files changed, 123 insertions(+), 1 deletions(-)

Comments

Simon Glass Nov. 14, 2012, 6:45 p.m. UTC | #1 
Hi,

On Wed, Nov 14, 2012 at 1:11 AM, Rajeshwari Shinde
<rajeshwari.s@samsung.com> wrote:
> Functions added to get the I2C bus number and reset I2C bus using
> FDT node.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
> ---
> Changes in V2:
>         - Added periph id to I2C bus structure.
>         - Modified i2c_get_bus_num_fdt function to compare with node.
>         - Board i2c init moved to driver in case of FDT.

This looks good to me, apart from a small thing you can probably drop below.

>  drivers/i2c/s3c24x0_i2c.c |   90 ++++++++++++++++++++++++++++++++++++++++++++-
>  drivers/i2c/s3c24x0_i2c.h |    8 ++++
>  include/i2c.h             |   26 +++++++++++++
>  3 files changed, 123 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c
> index 9bc4c7f..840585d 100644
> --- a/drivers/i2c/s3c24x0_i2c.c
> +++ b/drivers/i2c/s3c24x0_i2c.c
> @@ -27,9 +27,11 @@
>   */
>
>  #include <common.h>
> +#include <fdtdec.h>
>  #ifdef CONFIG_EXYNOS5
>  #include <asm/arch/clk.h>
>  #include <asm/arch/cpu.h>
> +#include <asm/arch/pinmux.h>
>  #else
>  #include <asm/arch/s3c24x0_cpu.h>
>  #endif
> @@ -60,7 +62,14 @@
>  #define I2C_TIMEOUT 1          /* 1 second */
>
>
> -static unsigned int g_current_bus;     /* Stores Current I2C Bus */
> +/*
> + * For SPL boot some boards need i2c before SDRAM is initialised so force
> + * variables to live in SRAM
> + */
> +static unsigned int g_current_bus __attribute__((section(".data")));
> +static struct s3c24x0_i2c_bus i2c_bus[CONFIG_MAX_I2C_NUM]
> +                       __attribute__((section(".data")));
> +static int i2c_busses __attribute__((section(".data")));
>
>  #ifndef CONFIG_EXYNOS5
>  static int GetI2CSDA(void)
> @@ -507,4 +516,83 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
>                 (i2c, I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer,
>                  len) != 0);
>  }
> +
> +#ifdef CONFIG_OF_CONTROL
> +void board_i2c_init(const void *blob)
> +{
> +
> +       int node_list[CONFIG_MAX_I2C_NUM];
> +       int count, i;
> +
> +       count = fdtdec_find_aliases_for_id(blob, "i2c",
> +               COMPAT_SAMSUNG_S3C2440_I2C, node_list,
> +               CONFIG_MAX_I2C_NUM);
> +       for (i = 0; i < count; i++) {
> +               struct s3c24x0_i2c_bus *bus;
> +               int node = node_list[i];
> +
> +               if (node < 0)
> +                       continue;
> +               bus = &i2c_bus[i];
> +               bus->regs = (struct s3c24x0_i2c *)
> +                       fdtdec_get_addr(blob, node, "reg");
> +               bus->id = (enum periph_id)
> +                       fdtdec_get_int(blob, node, "samsung,periph-id", -1);
> +               bus->node = node;
> +               bus->bus_num = i2c_busses++;
> +               exynos_pinmux_config(bus->id, 0);
> +       }
> +
> +}
> +
> +static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx)
> +{
> +       if (bus_idx < i2c_busses)
> +               return &i2c_bus[bus_idx];
> +       debug("Undefined bus: %d\n", bus_idx);
> +       return NULL;
> +}
> +
> +int i2c_get_bus_num_fdt(const void *blob, int node)
> +{
> +       enum fdt_compat_id compat;
> +       int i;
> +
> +       compat = fdtdec_lookup(blob, node);
> +       if (compat != COMPAT_SAMSUNG_S3C2440_I2C) {
> +               debug("%s: Not a supported I2C node\n", __func__);
> +               return -1;
> +       }

I think you can drop this check, since your code immediately below
will handle a missing node.

> +       for (i = 0; i < i2c_busses; i++) {
> +               if (node == i2c_bus[i].node)
> +                       return i;
> +       }
> +
> +       debug("%s: Can't find any matched I2C bus\n", __func__);
> +       return -1;
> +}
> +
> +int i2c_reset_port_fdt(const void *blob, int node)
> +{
> +       struct s3c24x0_i2c_bus *i2c;
> +
> +       int bus;
> +
> +       bus = i2c_get_bus_num_fdt(blob, node);
> +       if (bus < 0) {
> +               debug("could not get bus for node %d\n", node);
> +               return -1;
> +       }
> +       i2c = get_bus(bus);
> +       if (!i2c) {
> +               debug("get_bus() failed for node node %d\n", node);
> +               return -1;
> +       }
> +
> +       i2c_ch_init(i2c->regs, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
> +
> +       return 0;
> +}
> +#endif
> +
>  #endif /* CONFIG_HARD_I2C */
> diff --git a/drivers/i2c/s3c24x0_i2c.h b/drivers/i2c/s3c24x0_i2c.h
> index 2dd4b06..1243bf1 100644
> --- a/drivers/i2c/s3c24x0_i2c.h
> +++ b/drivers/i2c/s3c24x0_i2c.h
> @@ -30,4 +30,12 @@ struct s3c24x0_i2c {
>         u32     iicds;
>         u32     iiclc;
>  };
> +
> +struct s3c24x0_i2c_bus {
> +       int node;       /* device tree node */
> +       int bus_num;    /* i2c bus number */
> +       struct s3c24x0_i2c *regs;
> +       enum periph_id id;
> +};
> +
>  #endif /* _S3C24X0_I2C_H */
> diff --git a/include/i2c.h b/include/i2c.h
> index 16f099d..efb097f 100644
> --- a/include/i2c.h
> +++ b/include/i2c.h
> @@ -262,4 +262,30 @@ extern int get_multi_scl_pin(void);
>  extern int get_multi_sda_pin(void);
>  extern int multi_i2c_init(void);
>  #endif
> +
> +/**
> + * Get FDT values for i2c bus.
> + *
> + * @param blob  Device tree blbo
> + * @return the number of I2C bus
> + */
> +void board_i2c_init(const void *blob);
> +
> +/**
> + * Find the I2C bus number by given a FDT I2C node.
> + *
> + * @param blob  Device tree blbo
> + * @param node  FDT I2C node to find
> + * @return the number of I2C bus (zero based), or -1 on error
> + */
> +int i2c_get_bus_num_fdt(const void *blob, int node);
> +
> +/**
> + * Reset the I2C bus represented by the given a FDT I2C node.
> + *
> + * @param blob  Device tree blbo
> + * @param node  FDT I2C node to find
> + * @return 0 if port was reset, -1 if not found
> + */
> +int i2c_reset_port_fdt(const void *blob, int node);
>  #endif /* _I2C_H_ */
> --
> 1.7.4.4
>

Regards,
Simon
Heiko Schocher Nov. 15, 2012, 6:59 a.m. UTC | #2 
Hello Rajeshwari,

On 14.11.2012 10:11, Rajeshwari Shinde wrote:
> Functions added to get the I2C bus number and reset I2C bus using
> FDT node.
>
> Signed-off-by: Simon Glass<sjg@chromium.org>
> Signed-off-by: Rajeshwari Shinde<rajeshwari.s@samsung.com>
> ---
> Changes in V2:
> 	- Added periph id to I2C bus structure.
> 	- Modified i2c_get_bus_num_fdt function to compare with node.
> 	- Board i2c init moved to driver in case of FDT.
>   drivers/i2c/s3c24x0_i2c.c |   90 ++++++++++++++++++++++++++++++++++++++++++++-
>   drivers/i2c/s3c24x0_i2c.h |    8 ++++
>   include/i2c.h             |   26 +++++++++++++
>   3 files changed, 123 insertions(+), 1 deletions(-)

patch looks good, just some nitpicking comments ...

> diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c
> index 9bc4c7f..840585d 100644
> --- a/drivers/i2c/s3c24x0_i2c.c
> +++ b/drivers/i2c/s3c24x0_i2c.c
[...]
> @@ -507,4 +516,83 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
>   		(i2c, I2C_WRITE, chip<<  1,&xaddr[4 - alen], alen, buffer,
>   		 len) != 0);
>   }
> +
> +#ifdef CONFIG_OF_CONTROL
> +void board_i2c_init(const void *blob)
> +{
> +
> +	int node_list[CONFIG_MAX_I2C_NUM];
> +	int count, i;
> +
> +	count = fdtdec_find_aliases_for_id(blob, "i2c",
> +		COMPAT_SAMSUNG_S3C2440_I2C, node_list,
> +		CONFIG_MAX_I2C_NUM);
> +	for (i = 0; i<  count; i++) {
> +		struct s3c24x0_i2c_bus *bus;
> +		int node = node_list[i];
> +
> +		if (node<  0)
> +			continue;
> +		bus =&i2c_bus[i];
                      ^
                      space please
> +		bus->regs = (struct s3c24x0_i2c *)
> +			fdtdec_get_addr(blob, node, "reg");
> +		bus->id = (enum periph_id)
> +			fdtdec_get_int(blob, node, "samsung,periph-id", -1);
> +		bus->node = node;
> +		bus->bus_num = i2c_busses++;
> +		exynos_pinmux_config(bus->id, 0);
> +	}
> +
> +}
> +
> +static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx)
> +{
> +	if (bus_idx<  i2c_busses)
                    ^
                    space please
> +		return&i2c_bus[bus_idx];
                       ^
                       space please
> +	debug("Undefined bus: %d\n", bus_idx);
> +	return NULL;
> +}
> +
> +int i2c_get_bus_num_fdt(const void *blob, int node)
> +{
> +	enum fdt_compat_id compat;
> +	int i;
> +
> +	compat = fdtdec_lookup(blob, node);
> +	if (compat != COMPAT_SAMSUNG_S3C2440_I2C) {
> +		debug("%s: Not a supported I2C node\n", __func__);
> +		return -1;
> +	}
> +	for (i = 0; i<  i2c_busses; i++) {
> +		if (node == i2c_bus[i].node)
> +			return i;
> +	}
> +
> +	debug("%s: Can't find any matched I2C bus\n", __func__);
> +	return -1;
> +}
> +
> +int i2c_reset_port_fdt(const void *blob, int node)
> +{
> +	struct s3c24x0_i2c_bus *i2c;
> +
> +	int bus;
> +
> +	bus = i2c_get_bus_num_fdt(blob, node);
> +	if (bus<  0) {
                ^
                space
> +		debug("could not get bus for node %d\n", node);
> +		return -1;
> +	}
> +	i2c = get_bus(bus);
> +	if (!i2c) {
> +		debug("get_bus() failed for node node %d\n", node);
> +		return -1;
> +	}
> +
> +	i2c_ch_init(i2c->regs, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
> +
> +	return 0;
> +}
> +#endif
> +
>   #endif /* CONFIG_HARD_I2C */
> diff --git a/drivers/i2c/s3c24x0_i2c.h b/drivers/i2c/s3c24x0_i2c.h
> index 2dd4b06..1243bf1 100644
> --- a/drivers/i2c/s3c24x0_i2c.h
> +++ b/drivers/i2c/s3c24x0_i2c.h
> @@ -30,4 +30,12 @@ struct s3c24x0_i2c {
>   	u32	iicds;
>   	u32	iiclc;
>   };
> +
> +struct s3c24x0_i2c_bus {
> +	int node;	/* device tree node */
> +	int bus_num;	/* i2c bus number */
> +	struct s3c24x0_i2c *regs;
> +	enum periph_id id;
> +};
> +
>   #endif /* _S3C24X0_I2C_H */
> diff --git a/include/i2c.h b/include/i2c.h
> index 16f099d..efb097f 100644
> --- a/include/i2c.h
> +++ b/include/i2c.h
> @@ -262,4 +262,30 @@ extern int get_multi_scl_pin(void);
>   extern int get_multi_sda_pin(void);
>   extern int multi_i2c_init(void);
>   #endif
> +
> +/**
> + * Get FDT values for i2c bus.
> + *
> + * @param blob  Device tree blbo
                                ^
                                blob
> + * @return the number of I2C bus
> + */
> +void board_i2c_init(const void *blob);
> +
> +/**
> + * Find the I2C bus number by given a FDT I2C node.
> + *
> + * @param blob  Device tree blbo
                                ^
                                blob
> + * @param node  FDT I2C node to find
> + * @return the number of I2C bus (zero based), or -1 on error
> + */
> +int i2c_get_bus_num_fdt(const void *blob, int node);
> +
> +/**
> + * Reset the I2C bus represented by the given a FDT I2C node.
> + *
> + * @param blob  Device tree blbo
> + * @param node  FDT I2C node to find
> + * @return 0 if port was reset, -1 if not found
> + */
> +int i2c_reset_port_fdt(const void *blob, int node);
>   #endif	/* _I2C_H_ */

Thanks!

Reviewed-by: Heiko Schocher <hs@denx.de>

bye,
Heiko
Rajeshwari Birje Nov. 15, 2012, 11 a.m. UTC | #3 
Hi Heiko,

Thank you for the comments will modify the same and resend the patch.

Regards,
Rajeshwari Shinde.

On Thu, Nov 15, 2012 at 12:29 PM, Heiko Schocher <hs@denx.de> wrote:
> Hello Rajeshwari,
>
>
> On 14.11.2012 10:11, Rajeshwari Shinde wrote:
>>
>> Functions added to get the I2C bus number and reset I2C bus using
>> FDT node.
>>
>> Signed-off-by: Simon Glass<sjg@chromium.org>
>> Signed-off-by: Rajeshwari Shinde<rajeshwari.s@samsung.com>
>> ---
>> Changes in V2:
>>         - Added periph id to I2C bus structure.
>>         - Modified i2c_get_bus_num_fdt function to compare with node.
>>         - Board i2c init moved to driver in case of FDT.
>>   drivers/i2c/s3c24x0_i2c.c |   90
>> ++++++++++++++++++++++++++++++++++++++++++++-
>>   drivers/i2c/s3c24x0_i2c.h |    8 ++++
>>   include/i2c.h             |   26 +++++++++++++
>>   3 files changed, 123 insertions(+), 1 deletions(-)
>
>
> patch looks good, just some nitpicking comments ...
>
>
>> diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c
>> index 9bc4c7f..840585d 100644
>> --- a/drivers/i2c/s3c24x0_i2c.c
>> +++ b/drivers/i2c/s3c24x0_i2c.c
>
> [...]
>>
>> @@ -507,4 +516,83 @@ int i2c_write(uchar chip, uint addr, int alen, uchar
>> *buffer, int len)
>>                 (i2c, I2C_WRITE, chip<<  1,&xaddr[4 - alen], alen, buffer,
>>
>>                  len) != 0);
>>   }
>> +
>> +#ifdef CONFIG_OF_CONTROL
>> +void board_i2c_init(const void *blob)
>> +{
>> +
>> +       int node_list[CONFIG_MAX_I2C_NUM];
>> +       int count, i;
>> +
>> +       count = fdtdec_find_aliases_for_id(blob, "i2c",
>> +               COMPAT_SAMSUNG_S3C2440_I2C, node_list,
>> +               CONFIG_MAX_I2C_NUM);
>> +       for (i = 0; i<  count; i++) {
>> +               struct s3c24x0_i2c_bus *bus;
>> +               int node = node_list[i];
>> +
>> +               if (node<  0)
>> +                       continue;
>> +               bus =&i2c_bus[i];
>
>                      ^
>                      space please
>
>> +               bus->regs = (struct s3c24x0_i2c *)
>> +                       fdtdec_get_addr(blob, node, "reg");
>> +               bus->id = (enum periph_id)
>> +                       fdtdec_get_int(blob, node, "samsung,periph-id",
>> -1);
>> +               bus->node = node;
>> +               bus->bus_num = i2c_busses++;
>> +               exynos_pinmux_config(bus->id, 0);
>> +       }
>> +
>> +}
>> +
>> +static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx)
>> +{
>> +       if (bus_idx<  i2c_busses)
>
>                    ^
>                    space please
>>
>> +               return&i2c_bus[bus_idx];
>
>                       ^
>                       space please
>
>> +       debug("Undefined bus: %d\n", bus_idx);
>> +       return NULL;
>> +}
>> +
>> +int i2c_get_bus_num_fdt(const void *blob, int node)
>> +{
>> +       enum fdt_compat_id compat;
>> +       int i;
>> +
>> +       compat = fdtdec_lookup(blob, node);
>> +       if (compat != COMPAT_SAMSUNG_S3C2440_I2C) {
>> +               debug("%s: Not a supported I2C node\n", __func__);
>> +               return -1;
>> +       }
>> +       for (i = 0; i<  i2c_busses; i++) {
>> +               if (node == i2c_bus[i].node)
>> +                       return i;
>> +       }
>> +
>> +       debug("%s: Can't find any matched I2C bus\n", __func__);
>> +       return -1;
>> +}
>> +
>> +int i2c_reset_port_fdt(const void *blob, int node)
>> +{
>> +       struct s3c24x0_i2c_bus *i2c;
>> +
>> +       int bus;
>> +
>> +       bus = i2c_get_bus_num_fdt(blob, node);
>> +       if (bus<  0) {
>
>                ^
>                space
>
>> +               debug("could not get bus for node %d\n", node);
>> +               return -1;
>> +       }
>> +       i2c = get_bus(bus);
>> +       if (!i2c) {
>> +               debug("get_bus() failed for node node %d\n", node);
>> +               return -1;
>> +       }
>> +
>> +       i2c_ch_init(i2c->regs, CONFIG_SYS_I2C_SPEED,
>> CONFIG_SYS_I2C_SLAVE);
>> +
>> +       return 0;
>> +}
>> +#endif
>> +
>>   #endif /* CONFIG_HARD_I2C */
>> diff --git a/drivers/i2c/s3c24x0_i2c.h b/drivers/i2c/s3c24x0_i2c.h
>> index 2dd4b06..1243bf1 100644
>> --- a/drivers/i2c/s3c24x0_i2c.h
>> +++ b/drivers/i2c/s3c24x0_i2c.h
>> @@ -30,4 +30,12 @@ struct s3c24x0_i2c {
>>         u32     iicds;
>>         u32     iiclc;
>>   };
>> +
>> +struct s3c24x0_i2c_bus {
>> +       int node;       /* device tree node */
>> +       int bus_num;    /* i2c bus number */
>> +       struct s3c24x0_i2c *regs;
>> +       enum periph_id id;
>> +};
>> +
>>   #endif /* _S3C24X0_I2C_H */
>> diff --git a/include/i2c.h b/include/i2c.h
>> index 16f099d..efb097f 100644
>> --- a/include/i2c.h
>> +++ b/include/i2c.h
>> @@ -262,4 +262,30 @@ extern int get_multi_scl_pin(void);
>>   extern int get_multi_sda_pin(void);
>>   extern int multi_i2c_init(void);
>>   #endif
>> +
>> +/**
>> + * Get FDT values for i2c bus.
>> + *
>> + * @param blob  Device tree blbo
>
>                                ^
>                                blob
>
>> + * @return the number of I2C bus
>> + */
>> +void board_i2c_init(const void *blob);
>> +
>> +/**
>> + * Find the I2C bus number by given a FDT I2C node.
>> + *
>> + * @param blob  Device tree blbo
>
>                                ^
>                                blob
>
>> + * @param node  FDT I2C node to find
>> + * @return the number of I2C bus (zero based), or -1 on error
>> + */
>> +int i2c_get_bus_num_fdt(const void *blob, int node);
>> +
>> +/**
>> + * Reset the I2C bus represented by the given a FDT I2C node.
>> + *
>> + * @param blob  Device tree blbo
>> + * @param node  FDT I2C node to find
>> + * @return 0 if port was reset, -1 if not found
>> + */
>> +int i2c_reset_port_fdt(const void *blob, int node);
>>   #endif        /* _I2C_H_ */
>
>
> Thanks!
>
> Reviewed-by: Heiko Schocher <hs@denx.de>
>
> bye,
> Heiko
> --
> DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
>
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Heiko Schocher Nov. 19, 2012, 8:54 a.m. UTC | #4 
Hello Rajeshwari,

On 14.11.2012 10:11, Rajeshwari Shinde:wrote
> Functions added to get the I2C bus number and reset I2C bus using
> FDT node.
>
> Signed-off-by: Simon Glass<sjg@chromium.org>
> Signed-off-by: Rajeshwari Shinde<rajeshwari.s@samsung.com>
> ---
> Changes in V2:
> 	- Added periph id to I2C bus structure.
> 	- Modified i2c_get_bus_num_fdt function to compare with node.
> 	- Board i2c init moved to driver in case of FDT.
>   drivers/i2c/s3c24x0_i2c.c |   90 ++++++++++++++++++++++++++++++++++++++++++++-
>   drivers/i2c/s3c24x0_i2c.h |    8 ++++
>   include/i2c.h             |   26 +++++++++++++
>   3 files changed, 123 insertions(+), 1 deletions(-)

Acked-by: Heiko Schocher <hs@denx.de>

bye,
Heiko
diff mbox

Patch

diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c
index 9bc4c7f..840585d 100644
--- a/drivers/i2c/s3c24x0_i2c.c
+++ b/drivers/i2c/s3c24x0_i2c.c
@@ -27,9 +27,11 @@ 
  */
 
 #include <common.h>
+#include <fdtdec.h>
 #ifdef CONFIG_EXYNOS5
 #include <asm/arch/clk.h>
 #include <asm/arch/cpu.h>
+#include <asm/arch/pinmux.h>
 #else
 #include <asm/arch/s3c24x0_cpu.h>
 #endif
@@ -60,7 +62,14 @@ 
 #define I2C_TIMEOUT 1		/* 1 second */
 
 
-static unsigned int g_current_bus;	/* Stores Current I2C Bus */
+/*
+ * For SPL boot some boards need i2c before SDRAM is initialised so force
+ * variables to live in SRAM
+ */
+static unsigned int g_current_bus __attribute__((section(".data")));
+static struct s3c24x0_i2c_bus i2c_bus[CONFIG_MAX_I2C_NUM]
+			__attribute__((section(".data")));
+static int i2c_busses __attribute__((section(".data")));
 
 #ifndef CONFIG_EXYNOS5
 static int GetI2CSDA(void)
@@ -507,4 +516,83 @@  int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
 		(i2c, I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer,
 		 len) != 0);
 }
+
+#ifdef CONFIG_OF_CONTROL
+void board_i2c_init(const void *blob)
+{
+
+	int node_list[CONFIG_MAX_I2C_NUM];
+	int count, i;
+
+	count = fdtdec_find_aliases_for_id(blob, "i2c",
+		COMPAT_SAMSUNG_S3C2440_I2C, node_list,
+		CONFIG_MAX_I2C_NUM);
+	for (i = 0; i < count; i++) {
+		struct s3c24x0_i2c_bus *bus;
+		int node = node_list[i];
+
+		if (node < 0)
+			continue;
+		bus = &i2c_bus[i];
+		bus->regs = (struct s3c24x0_i2c *)
+			fdtdec_get_addr(blob, node, "reg");
+		bus->id = (enum periph_id)
+			fdtdec_get_int(blob, node, "samsung,periph-id", -1);
+		bus->node = node;
+		bus->bus_num = i2c_busses++;
+		exynos_pinmux_config(bus->id, 0);
+	}
+
+}
+
+static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx)
+{
+	if (bus_idx < i2c_busses)
+		return &i2c_bus[bus_idx];
+	debug("Undefined bus: %d\n", bus_idx);
+	return NULL;
+}
+
+int i2c_get_bus_num_fdt(const void *blob, int node)
+{
+	enum fdt_compat_id compat;
+	int i;
+
+	compat = fdtdec_lookup(blob, node);
+	if (compat != COMPAT_SAMSUNG_S3C2440_I2C) {
+		debug("%s: Not a supported I2C node\n", __func__);
+		return -1;
+	}
+	for (i = 0; i < i2c_busses; i++) {
+		if (node == i2c_bus[i].node)
+			return i;
+	}
+
+	debug("%s: Can't find any matched I2C bus\n", __func__);
+	return -1;
+}
+
+int i2c_reset_port_fdt(const void *blob, int node)
+{
+	struct s3c24x0_i2c_bus *i2c;
+
+	int bus;
+
+	bus = i2c_get_bus_num_fdt(blob, node);
+	if (bus < 0) {
+		debug("could not get bus for node %d\n", node);
+		return -1;
+	}
+	i2c = get_bus(bus);
+	if (!i2c) {
+		debug("get_bus() failed for node node %d\n", node);
+		return -1;
+	}
+
+	i2c_ch_init(i2c->regs, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+
+	return 0;
+}
+#endif
+
 #endif /* CONFIG_HARD_I2C */
diff --git a/drivers/i2c/s3c24x0_i2c.h b/drivers/i2c/s3c24x0_i2c.h
index 2dd4b06..1243bf1 100644
--- a/drivers/i2c/s3c24x0_i2c.h
+++ b/drivers/i2c/s3c24x0_i2c.h
@@ -30,4 +30,12 @@  struct s3c24x0_i2c {
 	u32	iicds;
 	u32	iiclc;
 };
+
+struct s3c24x0_i2c_bus {
+	int node;	/* device tree node */
+	int bus_num;	/* i2c bus number */
+	struct s3c24x0_i2c *regs;
+	enum periph_id id;
+};
+
 #endif /* _S3C24X0_I2C_H */
diff --git a/include/i2c.h b/include/i2c.h
index 16f099d..efb097f 100644
--- a/include/i2c.h
+++ b/include/i2c.h
@@ -262,4 +262,30 @@  extern int get_multi_scl_pin(void);
 extern int get_multi_sda_pin(void);
 extern int multi_i2c_init(void);
 #endif
+
+/**
+ * Get FDT values for i2c bus.
+ *
+ * @param blob  Device tree blbo
+ * @return the number of I2C bus
+ */
+void board_i2c_init(const void *blob);
+
+/**
+ * Find the I2C bus number by given a FDT I2C node.
+ *
+ * @param blob  Device tree blbo
+ * @param node  FDT I2C node to find
+ * @return the number of I2C bus (zero based), or -1 on error
+ */
+int i2c_get_bus_num_fdt(const void *blob, int node);
+
+/**
+ * Reset the I2C bus represented by the given a FDT I2C node.
+ *
+ * @param blob  Device tree blbo
+ * @param node  FDT I2C node to find
+ * @return 0 if port was reset, -1 if not found
+ */
+int i2c_reset_port_fdt(const void *blob, int node);
 #endif	/* _I2C_H_ */