It sounds like u-boot already has basic xHCI support, and you should contact the u-boot developers for further support of interrupt transfers.
http://lists.denx.de/mailman/listinfo/u-boot or https://lists.sourceforge.net/lists/listinfo/u-boot-users Disregard my comments about bit-banging the EHCI interfaces. Sarah Sharp On Tue, Apr 09, 2013 at 09:38:17AM +0530, Puneet Sharma wrote: > Hello Sarah, > > Thanks a lot for the information. For your information i am successfully > able to enumerate USB device(USB keyboard) over XHCI port by the help of > XHCI Stack patch provided in u-boot and also able to do BULK transfer > over Mass storage device. > > After successfully able to do CONTROL and BULK transfer i decided to go > for INTERRUPT transfer which i dont know is possible or not. Definately > i dont have deep knowledge about Linux USB stack and so i posted the > query to get some understanding of it. > > Also, when you say EHCI can bit-bang the interface what do you mean by > that?? > > Thanks > Puneet > > On Tue, 2013-04-09 at 04:31 +0530, Sarah Sharp wrote: > > The Linux xHCI driver relies on the USB core for setup. You really > > don't want to attempt to to separate the two. You can't get "just" > > interrupts for transfers either -- you need to do a lot of xHCI host > > setup before you can even send a control transfer to the device (which > > is necessary to find out whether it *is* a keyboard). > > > > Also, xHCI is not like EHCI, where you can bit-bang the interface. You > > have to have MMIO and DMA set up before you can use the xHCI host. You > > might be able to get away without having interrupts and polling the > > event ring, but I've never tried using any xHCI hosts that way. > > > > Also, I don't know what the license is for uboot, but you should know > > that the xHCI driver is GPL v2 only, and we can't change that. > > > > If the license is ok, and you want to take a stab at using the code, > > it's in drivers/usb/host/xhci*, with some bits in > > drivers/usb/host/pci-quirks.c. > > > > I think you've got some serious yak-shaving ahead of you, so you should > > think about whether you actually want to add xHCI support to uboot. > > It's clear that you don't know much about the Linux USB stack, and I'm > > afraid porting the xHCI driver code over to uboot is going to be pretty > > painful for you. > > > > Sarah Sharp > > > > On Wed, Apr 03, 2013 at 11:23:56AM +0530, Puneet Sharma wrote: > > > Hello Sarah, > > > > > > > > > I want to test USB keyboard for XHCI in u-boot and to do that i need the > > > Interrupt transfer code in XHCI controller driver. If possible, can you > > > help me to give that piece of code or can you help me to figure out in > > > kernel where can i find it so that i can try to replicate it in u-boot > > > and make it work. > > > > > > > > > Thanks & Regards > > > -- > > > Puneet Sharma > > > <[email protected]<mailto:[email protected]>> > > > > > > ________________________________ > > > The information contained in this email and any attachments is > > > confidential and may be subject to copyright or other intellectual > > > property protection. If you are not the intended recipient, you are not > > > authorized to use or disclose this information, and we request that you > > > notify us by reply mail or telephone and delete the original message from > > > your mail system. > > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
