[U-Boot] [PATCH v2 3/5] pmic_fsl: Introduce CONFIG_SYS_FSL_PMIC_I2C_LENGTH

[Lukasz Majewski]

Hi Stefano,

> Am 16/10/2012 01:32, schrieb Fabio Estevam:
> > From: Fabio Estevam <fabio.estevam at freescale.com>
> > 
> > Introduce CONFIG_SYS_FSL_PMIC_I2C_LENGTH to configure the number of
> > bytes that are used to communicate with the PMIC via I2C.
> > 
> > Instead of hardcoding the value, pass the number via a config
> > option.
> > 
> > This will be useful for adding support for PMIC MC34704 from
> > Freescale, which uses only one byte in its I2C protocol.
> > 
> > Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
> > ---
> 
> Hi Fabio,
> 
> > Changes since v2:
> > - No changes. Newly introduced in this series
> > 
> >  drivers/misc/pmic_fsl.c    |    2 +-
> >  include/configs/mx35pdk.h  |    1 +
> >  include/configs/mx53evk.h  |    1 +
> >  include/configs/mx53loco.h |    1 +
> >  4 files changed, 4 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/misc/pmic_fsl.c b/drivers/misc/pmic_fsl.c
> > index 0ff75ed..40c448b 100644
> > --- a/drivers/misc/pmic_fsl.c
> > +++ b/drivers/misc/pmic_fsl.c
> > @@ -53,7 +53,7 @@ int pmic_init(void)
> >  #elif defined(CONFIG_PMIC_I2C)
> >  	p->interface = PMIC_I2C;
> >  	p->hw.i2c.addr = CONFIG_SYS_FSL_PMIC_I2C_ADDR;
> > -	p->hw.i2c.tx_num = 3;
> > +	p->hw.i2c.tx_num = CONFIG_SYS_FSL_PMIC_I2C_LENGTH;
> 
> The bad thing with it is that it seems that each board can have a
> different value. However, this is bound to the selected pmic and not
> to the board. So IMHO it should not go into the board configuration
> file, but in the pmic specific initialization.
> 
> We share the same general code for all FSL PMIcs, so I am not sure
> which is the best way to do.  Maybe at the pmic initialization ?
> 
> I added Lucasz in CC, because he is working on the PMIC framework
> making it more flexible and with the possibility to have multiple
> PMIC (he has a board with more as one PMIC, even if they are
> integrated in teh same chip).
> 
> Lucasz changed (not yet merged) the pmic startup passing the number of
> I2C bus. So with the new interface, we could have something like:

I'm going to post another version of the patch in a few days.

> 
> 	pmic_init(I2C_PMIC);
>  	if (pmic_detect()) {
> 		p = pmic_get("FSL_PMIC");
> 
> The question is if it makes sense to pass also the tx_num to the init
> function, and moving to a
> 	pmic_init(i2cbus, txnum);

I'd like to avoid passing more data than necessary for the pmic_init.
I will investigate how it can be solved.

> 
> or is there a more elegant way ?
> 
> Best regards,
> Stefano
> 



-- 
Best regards,

Lukasz Majewski

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