On Thu, Jan 22, 2009 at 03:46:28PM -0600, david.hagood@xxxxxxxxx wrote: > I've spend the day tracking down a weird behavior on a Beagleboard with > 2.6.29-rc2-omap1. > > If you select the mode for the musb to operate in OnTheGo mode > (CONFIG_USB_MUSB_OTG), and if you compile the gadget drivers as modules, > the the USB port will NOT be brought up at system boot, even if it has a > USB mini-A cable plugged in (and thus should be in host mode, not gadget > mode). > > If you then modprobe an appropriate gadget driver, then the interface will > be brought up in host mode. that's expected. When you have otg selected, you can only let musb work when it's fully functional on both roles ;-) > If you DON'T modprobe a gadget driver, AND you attempt to force the port > to host mode by > echo host > /sys/devices/platform/musb_hdrc/mode > > Then we get a kernel page fault trying to change modes, even though we are > changing to host mode, which should be valid. > > It seems to me that either the port should be brought up in host mode if > no gadget drivers are loaded, and an attempt to switch to gadget mode > should fail if no driver is loaded, OR there should be a config options to > set what the default gadget driver is in the absence of one being loaded > by the system. not really, imagine what would happen, for example, if when you don't have a gadget driver loaded, the other side tries HNP... -- balbi -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
