On Thu, Oct 10, 2013 at 11:26:47AM -0500, Felipe Balbi wrote: > HI, > > On Thu, Oct 10, 2013 at 11:45:47PM +0800, Huang Rui wrote: > > On Thu, Oct 10, 2013 at 10:10:52AM -0500, Felipe Balbi wrote: > > > On Tue, Oct 08, 2013 at 10:28:29AM -0400, Alan Stern wrote: > > > > I also have a question for host and device mode switch at DWC3 > > controller with on PCI bus. I saw omap glue get extcon cable state to > > identify ID pin, am I right? > > > > if (extcon_get_cable_state(edev, "USB-HOST") == true) > > dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_GROUND); > > > > But I don't find any similar identification on PCI glue. So how PCI > > glue execute this action? > > OMAP is peculiar. Long story short, IP team always gives us some "nice" > easter eggs heh. In this case, ID pin status doesn't go straight from > transceiver to dwc3. Transceiver doesn't even know about the ID pin (or > vbus) states, those two lines are routed to a discrete comparator and we > need to manually write those to that mailbox you see. > So do you mean omap is able to use any other external connector to identify ID pin status, not only use transceiver? > On PCI land I'm assuming this won't be the case and ID/VBUS lines are > routed directly to a PHY with internal VBUS and ID comparators. If you > want to *force* the IP into host mode, there's a debugfs for that. Just > write "host" to /sys/kernel/debug/dwc3*/mode. > So if PCI land, we can't use internal ID pin status to switch the roles between host and device. we only should configure the role at user space by ourseleves for role switch, am I right? :) Thanks, Rui -- 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
