[U-Boot] [PATCH 0/3] usb: xhci: Add interrupt transfer support
Bin Meng
bmeng.cn at gmail.com
Thu Jun 29 09:16:59 UTC 2017
Hi Stefan,
On Thu, Jun 29, 2017 at 5:12 PM, Stefan Bruens
<stefan.bruens at rwth-aachen.de> wrote:
> On Donnerstag, 29. Juni 2017 08:13:41 CEST Stefan Roese wrote:
>> Hi Bin,
>>
>> On 29.06.2017 07:39, Bin Meng wrote:
>> > Hi Stefan,
>> >
>> > On Wed, Jun 28, 2017 at 8:47 PM, Stefan Roese <sr at denx.de> wrote:
> [...]
>> >>> I am more concerned about
>> >>> the "USB device descriptor short read (expected 18, got 8)". This
>> >>> message indicates U-Boot cannot get the device descriptor during set
>> >>> configuration process. So did you manage to get all USB devices that
>> >>> are connected on your board enumerated?
>> >>
>> >> Might be that I'm missing some keyboard / mouse, which I'm not
>> >> using and not really aware of. One USB port is connected to a
>> >> KVM switch, enumberating such devices. Here the log from U-Boot
>> >> and Linux again:
>> >>
>> >> => usb reset
>> >> resetting USB...
>> >> USB0: Register 7000820 NbrPorts 7
>> >> Starting the controller
>> >> USB XHCI 1.00
>> >> scanning bus 0 for devices... cannot reset port 1!?
>> >> USB device descriptor short read (expected 18, got 8)
>> >> 6 USB Device(s) found
>> >>
>> >> scanning usb for storage devices... 2 Storage Device(s) found
>> >>
>> >> => usb tree
>> >>
>> >> USB device tree:
>> >> 1 Hub (5 Gb/s, 0mA)
>> >>
>> >> | U-Boot XHCI Host Controller
>> >>
>> >> +-2 Hub (480 Mb/s, 100mA)
>> >>
>> >> +-3 Mass Storage (480 Mb/s, 98mA)
>> >>
>> >> | USBest Technology USB Mass Storage Device 09092207fbf0c4
>> >>
>> >> +-4 Hub (480 Mb/s, 2mA)
>> >>
>> >> | +-6 Mass Storage (480 Mb/s, 200mA)
>> >> |
>> >> | JetFlash Mass Storage Device 3281440601
>> >>
>> >> +-5 Vendor specific (5 Gb/s, 64mA)
>> >>
>> >> Realtek USB 10/100/1000 LAN 000002000000
>> >>
>> >> $ lsusb -t
>> >> /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/1p, 5000M
>> >>
>> >> |__ Port 1: Dev 2, If 0, Class=Vendor Specific Class, Driver=r8152,
>> >> |5000M
>> >>
>> >> /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 480M
>> >>
>> >> |__ Port 2: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
>> >> |
>> >> |__ Port 4: Dev 4, If 0, Class=Hub, Driver=hub/4p, 12M
>> >> |
>> >> |__ Port 1: Dev 6, If 1, Class=Human Interface Device,
>> >> |Driver=usbhid, 12M
>> >> |__ Port 1: Dev 6, If 2, Class=Human Interface Device,
>> >> |Driver=usbhid, 12M
>> >> |__ Port 1: Dev 6, If 0, Class=Human Interface Device,
>> >> |Driver=usbhid, 12M
>> >> |
>> >> |__ Port 4: Dev 3, If 0, Class=Mass Storage, Driver=usb-storage,
>> >> |480M
>> >> |__ Port 5: Dev 5, If 0, Class=Hub, Driver=hub/4p, 480M
>> >> |
>> >> |__ Port 1: Dev 7, If 0, Class=Mass Storage, Driver=usb-storage,
>> >> |480M
>> >>
>> >> Which event polling Kconfig option do I need to enable?
>> >
>> > The default one CONFIG_SYS_USB_EVENT_POLL should be OK. By comparing
>> > your U-Boot log and Linux one, I found the following devices were
>> >
>> > enumerated by Linux but not by U-Boot:
>> > |__ Port 1: Dev 6, If 1, Class=Human Interface Device,
>> >
>> > Driver=usbhid, 12M
>> >
>> > |__ Port 1: Dev 6, If 2, Class=Human Interface Device,
>> >
>> > Driver=usbhid, 12M
>> >
>> > |__ Port 1: Dev 6, If 0, Class=Human Interface Device,
>> >
>> > Driver=usbhid, 12M
>> >
>> > These devices are full speed devices. I believe the reason is that
>> > U-Boot encounters "USB device descriptor short read (expected 18, got
>> > 8)" so it does not continue the enumeration. As to why these full
>> > speed devices only return 8 bytes descriptors, this needs to be
>> > investigated. Which devices are they?
>>
>> This is my KVM switch with its USB keyboard and mouse. When I unplug
>> this USB cable, this message does not appear while running "usb reset".
>>
>> This also happen, when I only plug a USB mouse to this same USB
>> port:
>>
>> => usb reset
>> resetting USB...
>> USB0: Register 7000820 NbrPorts 7
>> Starting the controller
>> USB XHCI 1.00
>> scanning bus 0 for devices... USB device descriptor short read (expected 18,
>> got 8) 5 USB Device(s) found
>> scanning usb for storage devices... 2 Storage Device(s) found
>> => usb tree
>> USB device tree:
>> 1 Hub (5 Gb/s, 0mA)
>>
>> | U-Boot XHCI Host Controller
>>
>> +-2 Mass Storage (480 Mb/s, 98mA)
>>
>> | USBest Technology USB Mass Storage Device 09092207fbf0c4
>>
>> +-3 Hub (480 Mb/s, 2mA)
>>
>> | +-5 Mass Storage (480 Mb/s, 200mA)
>> |
>> | JetFlash Mass Storage Device 3281440601
>>
>> +-4 Vendor specific (5 Gb/s, 64mA)
>> Realtek USB 10/100/1000 LAN 000002000000
>>
>>
>> $ lsusb -t
>> /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/1p, 5000M
>>
>> |__ Port 1: Dev 2, If 0, Class=Vendor Specific Class, Driver=r8152,
>> |5000M
>>
>> /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 480M
>>
>> |__ Port 2: Dev 2, If 0, Class=Human Interface Device, Driver=usbhid,
>> |12M
>> |__ Port 2: Dev 2, If 1, Class=Human Interface Device, Driver=usbhid,
>> |12M
>> |__ Port 4: Dev 3, If 0, Class=Mass Storage, Driver=usb-storage, 480M
>> |__ Port 5: Dev 4, If 0, Class=Hub, Driver=hub/4p, 480M
>> |
>> |__ Port 1: Dev 5, If 0, Class=Mass Storage, Driver=usb-storage,
>> |480M
>
> U-Boot requests the whole USB Device descriptor, i.e. at least 18 bytes. *If*
> the devices bMaxPacketSize0 is 8, it will only return 8 bytes per IN transfer.
> If the driver fails to set the packet size according to the devices
> capabilities, the HC may only do one instead of multiple IN transfers, i.e.
> you end up with only 8 bytes.
>
> I you look at common/usb.c, usb_setup_descriptor(...), you can see it actually
> only requests *at least* 8 bytes. You should verify where you descriptor
> request is coming from. Either it failed to query the bMaxPacketSize0, or it
> somehow got reset, i.e. later requests are not split into multiple IN
> transfers.
>
Thanks for your information. Actually I suspect the same thing here. I
noticed the comment block in usb_setup_descriptor() before. Not like
other HCs, xHC does things differently (do_read is false in that
function).
Regards,
Bin
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