Hi, On 01/12/11 18:31, Johannes Reisinger wrote: > Hi Felipe, > > >> So you have an OTG transceiver to switch operation between host and >> device, right ? > > No, we have two distinct USB interfaces, one configured as host and > the other as device. No OTG at all. > >> Considering that, is the transceiver ULPI compliant ? if it is, then you >> can probably use the nop-xceiv driver for that. But you sure need a >> driver. > > Yes, the transceiver is ULPI compliant. > Within the kernel sources I found transceiver support only within the > 'otg' tree (but maybe I am missing something ...). Does this mean that > I need transceiver support only for OTG interfaces, but not for pure > host or device interfaces? > There is a drivers/usb/otg/ulpi.c generic driver. It has been put there a lot of time ago and I think by mistake. It can work with ULPI compliant transceivers and it does not care if the transceiver role is host or a device. ULPI transceivers are mostly autonomous in their nature and there are cases where no driver is required at all. ULPI transceivers can work with Host/Device/OTG ULPI Links (SoC interfaces). They do not require the Link to be OTG. Currently, to use the driver you will have to use OTG infrastructure in kernel, and also add some code to the platform support. -- Regards, Igor. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
