Re: [PATCH 2/4] of: DT quirks infrastructure

From: Maxime Bizon
Date: Thu Feb 19 2015 - 13:23:00 EST



On Thu, 2015-02-19 at 19:12 +0100, Sylvain Rochet wrote:

> Or use a 1-wire or I2C EEPROM to store your board information.

no, you don't reduce the human error probability.

eeprom needs to be preprogrammed, factory will at some point have a lot
of eeprom with different version, and will potentially equip the wrong
one.

much more error prone than them putting the resistor at the wrong place.

> Or, even better, if you have an I2C device, just chose a different
> address on each board for this device and then probe I2C devices in your
> boot loader until you found one you are looking for, this way, you don't
> need spare GPIO at all. You don't even need to populate the same I2C
> device on all boards, you can actually probe anything.

I'm not a fan of schemes where not probing something is not a definitive
sign of hardware failure.

--
Maxime


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