On Mon, Feb 09, 2015 at 10:27:53AM -0600, Felipe Balbi wrote: > Hi, Hi, > > On Sun, Feb 08, 2015 at 02:51:16PM -0700, Joseph Kogut wrote: > > I have an Intel Valleyview/Baytrail based device (specifically a Dell > > Venue 8 Pro 5830) that I'd like to be able to use the Linux Gadget > > subsystem on, but it seems that the controller isn't currently > > supported. I'm running the 3.19rc7 mainline release. > > > > The device has a micro AB connector. Based on my experiences with a > > similar (Merrifield) platform using Intel's own out of tree patchset > > that had working DRD support using a modified DWC3 driver, I suspected > > that the Baytrail platform I'm working on would also use the DWC3 > > driver. > > > > The output of "lspci -nn" shows: > > > > > 00:14.0 USB controller [0c03]: Intel Corporation Atom Processor > > > Z36xxx/Z37xxx Series USB xHCI [8086:0f35] (rev 09) > > hmm... looking at what we support today we for PCI, we support Baytrail, > Merrifield, SPTLP, SPTH, BSW (whatever these last three are) and AMD NL. > > However Baytrail is reported as 0x0f37, not 0x0f35. If you have a > micro-AB and then it ought to support peripheral mode. > > I have a feeling the problem you're having is the same David Cohen (in > Cc) has been trying to support upstream. The SoC has two controllers > inside, one is peripheral only while the other is host only; there's > discrete mux in front of them to mux the data lines to one or the other > controller. > > David, is this what's going on ? I don't have deep knowledge about this hardware, but after a quick look at internet it seems to be in similar case of Asus T100: The micro AB connector is used for charging only. Since it's BYT SoC, it sure has DWC3 controller. But it doesn't mean the micro AB connector reaches it. Br, David > > > Also, a string in the ACPI table tells me that the device uses a > > Synopsys XHCI core, though I'm not sure if it's DRD capable, or host > > only. > > > > > _DDN.Baytrail XHCI controller (Synopsys core/OTG) > > > > > > I tried adding the controller's PCI ID to drivers/usb/dwc3/dwc3-pci.c, > > and upon rebooting, the DWC3 module loaded, but reported: > > > > > [ 5.962605] dwc3 dwc3.0.auto: this is not a DesignWare USB3 DRD Core > > > > > > I don't know if this is the result of Dell messing with the ACPI > > table, as they seem prone to do, making the otherwise compatible > > hardware undetected by the proper driver, or if I'm just barking up > > the wrong tree. I think it's premature to file a bug report, > > considering the fact that I'm not yet sure this controller uses the > > DWC3 core. > > > > Attached is the acpi dump from the device in question. > > > > Thank you for your time, > > Joseph > > > > -- > balbi -- 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
