On Fri, Feb 26, 2010 at 4:22 AM, Greg KH <gre...@suse.de> wrote: > On Thu, Feb 25, 2010 at 08:31:43PM +0100, Kees Jongenburger wrote: > > On Thu, Feb 25, 2010 at 5:07 PM, Greg KH <gre...@suse.de> wrote: > > > On Thu, Feb 25, 2010 at 09:29:33PM +0530, Sriram Chadalavada wrote: > > >> The reason I ask about Linux USB OTG support is that it appears to be > > >> somewhat leading edge. > > > > > > Why do you say that? Linux has had OTG support for _many_ years, and > is > > > shipped in many devices. Actually most OTG devices you see in the > > > market are running Linux inside of them. > > > > I learned that most people when talking about OTG are actually talking > > about the ability for a device to act in either host or function mode. > > They don't care about the specs > > or special cables needed. I think the only kernel to support such > > feature without to much hassle is the omap kernel (using the > > tranciever API see > > http://www.linux-usb.org/gadget/h2-otg.html ). For portable device > > depending on the size I think it is only fair to have booth host and > > function mode. If the device is large > > a host and device port can be placed and for smaller devices like the > > N800 for example it's only fair to allow switching and while in > > usb-host mode provide at least 100ma. > > > > > > > > The problem is, OTG itself really isn't a good idea, and is difficult > to > > > handle on both the host and device side for a variety of reasons. I > > > would recommend not doing it if at all possible and just stick to a > > > "normal" type device interface instead. > > > > So what would normal be on something like the N900 or the EEE? I > > consider emptying a camera to the N900 is a real life senario ,to bad > > it doesn't support usb-host. > > Something "normal" would be what you describe above, the ability to be > either host or guest, but not necessarily the whole OTG mess of cabling > and negotiation that makes a device really a OTG one. Just use 2 plugs, > and switch the functionality depending on which is plugged in. Most > hardware supports this quite well these days. > > thanks, > > greg k-h >
Keene: You may already know that the Nokia 810 internet tablet supports USB-host. Correct me if I am wrong, what you are saying is that a portable device should provide 2 separate USB ports - host and slave but smaller devices such as the Nokia n900 could provide only one OTG (micro-AB) USB port ( that can switch between host or slave depending on whether a micro-A or micro-B plug is attached. Greg, You refer to the second option that does not require software support? Thanks, Ram _______________________________________________ Moblin dev Mailing List dev@moblin.org To manage or unsubscribe from this mailing list visit: http://lists.moblin.org/listinfo/dev or your user account on http://moblin.org once logged in. For more information on the Moblin Developer Mailing lists visit: http://moblin.org/community/mailing-lists
