On Fri, Dec 08, 2017 at 05:59:10PM +0200, Mathias Nyman wrote: > From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> > > xHCI compatible USB host controllers(i.e. super-speed USB3 controllers) > can be implemented with the Debug Capability(DbC). It presents a debug > device which is fully compliant with the USB framework and provides the > equivalent of a very high performance full-duplex serial link. The debug > capability operation model and registers interface are defined in 7.6.8 > of the xHCI specification, revision 1.1. > > The DbC debug device shares a root port with the xHCI host. By default, > the debug capability is disabled and the root port is assigned to xHCI. > When the DbC is enabled, the root port will be assigned to the DbC debug > device, and the xHCI sees nothing on this port. This implementation uses > a sysfs node named <dbc> under the xHCI device to manage the enabling > and disabling of the debug capability. > > When the debug capability is enabled, it will present a debug device > through the debug port. This debug device is fully compliant with the > USB3 framework, and it can be enumerated by a debug host on the other > end of the USB link. As soon as the debug device is configured, a TTY > serial device named /dev/ttyDBC0 will be created. > > Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> > Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx> This patch produces the following build warning for me: drivers/usb/host/xhci-dbgcap.c: In function ‘xhci_dbc_eps_exit’: drivers/usb/host/xhci-dbgcap.c:369:2: warning: ‘memset’ used with length equal to number of elements without multiplication by element size [-Wmemset-elt-size] memset(dbc->eps, 0, ARRAY_SIZE(dbc->eps)); ^~~~~~ Can you send a follow-on patch to fix it up? And you might want to update to a newer version of gcc :) thanks, greg k-h -- 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
