[U-Boot] [PATCH 1/3] misc:pmic: Support for voltage to register value conversion function

Lukasz Majewski l.majewski at samsung.com
Wed Mar 28 13:26:06 CEST 2012

Hi Stefano,

On Wed, 28 Mar 2012 12:26:46 +0200
Stefano Babic <sbabic at denx.de> wrote:

> On 28/03/2012 10:45, Lukasz Majewski wrote:
> > Support for voltage (in uV) to proper register value is added.
> > The function tied to this callback is often PMIC dependent
> > and shall be defined for each device.
> > 
> > Signed-off-by: Lukasz Majewski <l.majewski at samsung.com>
> > Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
> > Cc: Stefano Babic <sbabic at denx.de>
> > ---
> Hi Lukasz,
> >  
> > +int pmic_vol_to_reg(struct pmic *p, int uV)
> You added a new entry point to pmic, but you do not use it...I have
> not found in your patchset why it is necessary for you.

Rationale for this change is in commits following this one.
For trats Samsung target it is necessary to change the default voltage.

I think, that providing access to such a function as a pointer is the
best possible solution.

For example the MAX8997 and MAX8998 PMICs have different way of
calculating the value, which represents the LDO output value.

> I am not sure if we require to add this to the PMIC API or hide in the
> pmic specific code. Other PMICs has not a a register for different
> voltages, but only a bit inside the same register (this is the case
> for the Freescale's PMICs we currently support in u-boot).

I think, that it is easier to define function pointer in the pmic
structure, than separate functions and handling them in target platform

> Best regards,
> Stefano Babic

Best regards,

Lukasz Majewski

Samsung Poland R&D Center
Platform Group

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