On Wed, Feb 23, 2005 at 05:11:16PM -0500, Alan Stern wrote: > lsusb does make the queries (going through usbfs). lsusb _has_ to use > libusb; sysfs only includes information for active configurations whereas > lsusb wants to print out information for all configurations.
Is there a design reason for this, or is "expose information about inactive configurations in sysfs" a reasonable wishlist item, too? It might be useful, for example, for my trawl-sysfs-looking-for-pen-drives code to be able to include (in diagnostic output) descriptions of alternative configurations that the kernel didn't choose. For example, my Shuffle appears to have a 100mA configuration and a 500mA one; the kernel always chooses the 500mA one, even though it's attached to a bus-powered hub. If somebody is reporting problems with a device, the existance of the other configuration might be important. (I'm not sure what the difference is between the configurations--perhaps the 100mA configuration doesn't charge the device while it's plugged in.) By the way, would it be likely to cause problems (self-inflicted bugs aside) if I hacked up the configuration selection code to prefer lower- power configurations? hub.c:choose_configuration has a comment, "this should interact with hub power budgeting"; my case is specifically "two USB pen drives attached to a bus-powered hub". -- Glenn Maynard ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
