Re: [U-Boot] [PATCH 1/8] Add simple hwconfig infrastructure

On Fri, May 01, 2009 at 12:31:54AM +0200, Wolfgang Denk wrote:

Dear Anton,

In message 20090429215000.GA1092@oksana.dev.rtsoft.ru you wrote:

...

This patch implements simple hwconfig infrastructure: an interface for software knobs to control a hardware.

Thanks a lot.

...

3. We support hwconfig options with arguments. For example,

   set hwconfig dr_usb,dr_usb_mode:peripheral,dr_usb_phy_type:ulpi

   There are three hwconfig options selected:

   1. dr_usb - enable Dual-Role USB controller;
   2. dr_usb_mode:peripheral - USB in Function mode;
   3. dr_usb_phy_type:ulpi - USB should work with ULPI PHYs.

That gives a lot of typing, which in turn results in lots of typing errors, which in this case are probably nasty to debug.

Suggestion: instead of

set hwconfig dr_usb,dr_usb_mode:peripheral,dr_usb_phy_type:ulpi

use:

set hwconfig dr_usb:mode=peripheral,phy_type=ulpi

What do you think?

At first sight this looks great. But where should we stop? I mean, technically that is

dr_usb { mode = peripheral; phy_type = ulpi; };

I wonder if we want multi-level nesting capability, i.e.

dr_usb { mode = peripheral; phy { type = ulpi; clock = 48; }; };

We'd type it this way:

=> set hwconfig "

dr_usb { mode = peripheral; phy { type = ulpi; speed = 48; } } "

:-)

Or we can stop at one nesting level capability, just as you describe. Your suggestion is quite easy to implement, but full fledged parser is needed for the most generic case.

Thanks,