On 01/26/2016 03:36 PM, Greg Kroah-Hartman wrote: > On Tue, Jan 26, 2016 at 12:14:16PM +0800, Lu Baolu wrote: >> xHCI debug capability (DbC) is an optional functionality provided >> by an xHCI host controller. Software learns this capability by >> walking through the extended capability list in mmio of the host. >> >> This patch introduces the code to probe and initialize the debug >> capability hardware during early boot. With hardware initialization >> done, the debug target (system under debug which has DbC enabled) >> will present a debug device through the debug port. The debug device >> is fully compliant with the USB framework and provides the equivalent >> of a very high performance (USB3) full-duplex serial link between the >> debug host and target. >> >> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> >> --- >> MAINTAINERS | 7 + >> arch/x86/Kconfig.debug | 12 + >> drivers/usb/early/Makefile | 1 + > Why did you make a whole new subdirectory, just for your one driver? > Please don't do that, just put it in the host controller directory where > it belongs... I am sorry, but driver/usb/early is an existing subdirectory. $ ls drivers/usb/early/ ehci-dbgp.c Makefile If I understand it correctly, the "early" subdirectory is used to keep drivers which should be loaded during early boot stage. We already have code for EHCI debug port there with the filename ehci-dbgp.c. It is used to aid the developer to get kernel messages during early boot through EHCI debug port. What I have done is to implement the same thing with xHCI debug port. It's not part of xHCI host controller driver and it is executed even before xHCI driver is loaded. Thanks, Baolu > > -- 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
