On Tue, Oct 14, 2003 at 03:31:34PM -0400, G. Del Merritt wrote: > I've read Matthew Dharm's info/intro on USB Mass Storage: > > http://www2.one-eyed-alien.net/~mdharm/linux-usb/ > > I'm looking for a similar document that can help me answer more generic > USB-and-Linux questions, like these: > > - How much specific knowledge does the kernel need about a device? From > looking at kernel changelogs, I see a lot of "add support for device blah"; > it seems a waste of time to mod the kernel for each new device.
It all depends on the type of the device. For example, a USB keyboard almost always just works, no new support needed, while video cameras all need new drivers, as the protocol is different for every device. > - How can user-mode USB apps acquire reasonable access to a specific device > without compromising other USB devices also connected to the > system/hub? Is this purely a function of hotplugging and appropriate > agents, or does the kernel itself get in to the picture? There is a usbfs call to disconnect any existing usb driver from the device so that usbfs can talk to it. That is done from userspace. > - Is libusb the only API extant for user-mode applications? If not, what > else is there, and what are some of the trade-offs for using libusb vs. > other APIs? libusb is just a wrapper on top of usbfs. You can write raw usbfs calls if you want to. > - Is there USB support outside of the kernel? http://www.linux-usb.org/ > implies to me that there are other alternatives, based on a heading there, > "Kernel USB stack (aka Linus' Alternative USB stack)" Not that I know of. > I'm looking for something of a comprehensive USB-and-Linux roadmap, since I > feel I have a hole or two in my understanding that needs to be filled, and > my Google searches to date haven't helped. What do you need this information for? thanks, greg k-h ------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. SourceForge.net hosts over 70,000 Open Source Projects. See the people who have HELPED US provide better services: Click here: http://sourceforge.net/supporters.php _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
