On Thu, 30 Apr 2009 01:50:00 +0400 Anton Vorontsov avorontsov@ru.mvista.com wrote:
This patch implements simple hwconfig infrastructure: an interface for software knobs to control a hardware.
This is very simple implementation, i.e. it is implemented via `hwconfig' environment variable. Later we could write some "hwconfig <enable|disable|list>" commands, ncurses interface for Award BIOS-like interface, and frame-buffer interface for AMI GUI[1] BIOS-like interface with mouse support[2].
Current implementation details/limitations:
Doesn't support options dependencies and mutual exclusion. We can implement this by integrating apt-get[3] into the u-boot. But I didn't bother yet.
Since we don't implement hwconfig command, i.e. we're working with the environement directly, there is no way to tell that toggling a particular option will need a reboot to take an effect. So, for now it's advised to always reboot the target after modifying hwconfig variable.
We support hwconfig options with arguments. For example,
set hwconfig dr_usb,dr_usb_mode:peripheral,dr_usb_phy_type:ulpi
so a newbie displays his board's environment and sees the above line for the first time. It's not clear whether they will interpret the above as how you would have them:
There are three hwconfig options selected:
- dr_usb - enable Dual-Role USB controller;
- dr_usb_mode:peripheral - USB in Function mode;
- dr_usb_phy_type:ulpi - USB should work with ULPI PHYs.
or as something starting along the lines of "dr_usb and/or dr_usb_mode acquire the 'peripheral' setting,..." and then realize "peripheral,dr_usb_phy_type" doesn't make much sense, and have to revert to applying different 'weights' to the comma (,) and colon (:) token separator characters (to a native English speaker, a colon has a higher separation weight than the comma).
May I suggest something more clearer on the outset, such as:
set hwconfig "dr_usb=enable; dr_usb_mode=peripheral; dr_usb_phy_type=ulpi"
or
set hwconfig "usb=dr; dr_usb_mode=peripheral; dr_usb_phy_type=ulpi"
The purpose of this simple implementation is to define some internal API and then we can continue improving user experience by adding more mature interface, like hwconfig command with bells and whistles. Or not adding, if we feel that current interface fits its needs.
[1] http://en.wikipedia.org/wiki/American_Megatrends [2] Regarding ncurses and GUI with mouse support -- I'm just kidding.
phew, you had me for a second there :).
Kim