[U-Boot] [PATCH 13/17] post/i2c: Add ability to ignore I2C devices

Peter Tyser
2010-09-30T06:35:43Z

On Thu, 2010-09-30 at 08:10 +0200, Heiko Schocher wrote:
> Hello Peter,
>
> Peter Tyser wrote:
> > Add the ability to not report an I2C POST error for a set of given I2C
> > addresses on bootup. This is useful for the following cases:
> >
> > - Some form factors such as XMC and Compact PCI Express have an I2C
> > EEPROM whose address changes based on geographical address. Eg
> > installed in one slot its EEPROM address is, 0x50, in another its
> > 0x51, etc. This allows multiple devices to have their EEPROMs present
> > on the same I2C bus. Thus the I2C devices present for an XMC or
> > CPCIe card depend on if and where other cards are installed in the
> > same system.
> >
> > - Some cards have optional I2C devices. Eg one hardware build
> > configuration has different I2C devices than another.
> >
> > - Some cards have optional daughtercards with I2C devices on them.
> >
> > - I2C EEPROMs address range depends on their size. Its possible to
> > support differently size EEPROMs by only probing the EEPROM's base
> > address and ignoring the other addresses that are impacted by its
> > size.
> >
> > A new I2C_ADDR_IGNORE_LIST define has been added which specifies a list
> > of I2C addresses for the I2C POST to ignore.
> >
> > Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
> > CC: hs at denx.de
> > ---
> > post/drivers/i2c.c | 16 ++++++++++++++++
> > 1 files changed, 16 insertions(+), 0 deletions(-)
>
> Maybe you can add a little info in the README?

The existing I2C_ADDR_LIST isn't documented, so I didn't document this
addition. I'll mention them both in doc/README.POST.

> > diff --git a/post/drivers/i2c.c b/post/drivers/i2c.c
> > index 2dd128e..9e1fd50 100644
> > --- a/post/drivers/i2c.c
> > +++ b/post/drivers/i2c.c
> > @@ -40,6 +40,20 @@
> >
> > #if CONFIG_POST & CONFIG_SYS_POST_I2C
> >
> > +static int i2c_ignore_device(unsigned int chip)
> > +{
> > +#ifdef I2C_ADDR_IGNORE_LIST
>
> Hmm.. as this is only used in post code, this should be visible
> in the defines name, what with:
>
> I2C_POST_ADDR_IGNORE_LIST

I was following the lead of the existing I2C_ADDR_LIST define. Agreed
it should be named differently. I'll go with CONFIG_SYS_POST_I2C_ADDRS
and CONFIG_SYS_POST_I2C_IGNORES unless someone else chimes in.

Thanks for the review,
Peter