[U-Boot] [PATCH 0/2] arm nomadik: gpio and i2c

Alessandro Rubini rubini-list at gnudd.com
Mon Jul 20 11:31:02 CEST 2009


> what with deinit_pin(pin, function)? That would be in shape with init_pin()?

No, it's not clear what it is. I'd rename "init" to "setup", adding an AF
argument. So I can setup it as AF2, or as GPIO-OUT, or whatever.

> (There, we could also unset the marker, that this pin is no longer used
> for gpio ...)

No, I wouldn't like the marker. It's a boot loader, it shouldn't
overdo sanity checks.  Most of the times it runs the same "bootcmd"
over and over. In the rare but important case it's a debugging tool, it
shouldn't force policy, in my opinion (I already have problems with the
kernel gpiolib, that doesn't let me fix mishaps at will).

> Also, a board can have more then one gpio adapter, how we address
> such a case?

As Wolfgang suggested, we don't.  If atmel calls it PORTC-12 I have no
problem calling it gpio-76 by concatentating the ports as 0..31,
32..64, ...  It's still better to have a gpio command than doing "mw
<addr> <val>" over and over.

In my old-fashioned way, it should be as simple as possible, but no simpler.

/alessandro


More information about the U-Boot mailing list