From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: To: 9fans@cse.psu.edu Subject: Re: usbd - revision (Was: [9fans] USB developments) From: Fco.J.Ballesteros In-Reply-To: <20040115211012.K25947@cackle.proxima.alt.za> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Fri, 16 Jan 2004 08:34:15 +0100 Topicbox-Message-UUID: ba7bc85e-eacc-11e9-9e20-41e7f4b1d025 >> i was broadly happy with the kernel/user split, and >> the overall structure. the kernel device is essentially >> an IO multiplexor and i think that's about right. the kernel doesn't >> need to know about fancy hub trees or HID descriptors, >> and that also seems good to me. (for mouse and keyboard there >> are or were special boot-time modes one could use before usbd could run.) >> (in fact, usbd could probably devise/check the USB IO schedule too.) >> > Enter Nemo. I'll leave him to comment, I'm just a poorly informed > spectator. Regarding the hid, there's nothing special. It works in a back-compat mode (boot mode) while the system gets up, to allow you to type. Roughly, when usb gets up, it assumes that the system can speak its usb protocol and switches to it. The only special thing is that hid introduced the need to start usbd and usbhid at boot(8) time, since you must mount the new /dev/cons (fake) device before anyone opens it. But regarding this discussion, it's just another regular usb driver.