* OHCI: USB webcam works, but not on USB Hub
@ 2007-04-03 12:02 Michael Bueker
0 siblings, 0 replies; 5+ messages in thread
From: Michael Bueker @ 2007-04-03 12:02 UTC (permalink / raw)
To: linux-kernel
[please CC me on this thread]
Hi everyone,
My system has an nForce4 motherboard with an OHCI USB controller.
I'm using a USB Webcam with the gspca driver (from
http://mxhaard.free.fr/download.html), which has been working fine with the
latest kernels.
Today, I connected a USB Hub and the camera to it, after which it stopped
working with the error message:
> ERROR opening V4L interface
> : Function not implemented
However, it works fine when not connected to the Hub, but a motherboard's own
USB port. The Hub also works fine with any other USB device.
I googled around for a solution and found one for an older version of my
driver, where the (apparently very ugly) fix was to manually set a fixed
bandwidth for the USB device, instead of using a somehow other determined
value. See this posting for a more elaborate description:
http://lists.zerezo.com/spca50x-devs/msg00664.html
Now, I'm writing to this list because one of the followups to that post
(http://lists.zerezo.com/spca50x-devs/msg00665.html) states that this is due
to a problem with the Linux USB layer:
> pls file a bug "ohci driver can't handle low+fullspeed devices on the same
> root hub" to linux usb devel list.
That's about all I can tell you for now. I've attached two outputs of
lsusb -vv, one with the hub attached, with the camera and a USB stick
connected (notice the error message), and one without the hub and the
camera connected directly (which is the setup where it works fine).
Many thanks in advance for any responses,
Michael
--- lsusb -vv follows: camera and a USB stick connected to the hub
> can't get debug descriptor: Connection timed out
> ptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 1.10
> bDeviceClass 9 Hub
> bDeviceSubClass 0 Unused
> bDeviceProtocol 0 Full speed hub
> bMaxPacketSize0 64
> idVendor 0x0000
> idProduct 0x0000
> bcdDevice 2.06
> iManufacturer 3 Linux 2.6.19.7-mb6 ohci_hcd
> iProduct 2 OHCI Host Controller
> iSerial 1 0000:00:02.0
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 25
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0xe0
> Self Powered
> Remote Wakeup
> MaxPower 0mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 1
> bInterfaceClass 9 Hub
> bInterfaceSubClass 0 Unused
> bInterfaceProtocol 0 Full speed hub
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0002 1x 2 bytes
> bInterval 255
> Hub Descriptor:
> bLength 11
> bDescriptorType 41
> nNbrPorts 10
> wHubCharacteristic 0x0002
> No power switching (usb 1.0)
> Ganged overcurrent protection
> bPwrOn2PwrGood 1 * 2 milli seconds
> bHubContrCurrent 0 milli Ampere
> DeviceRemovable 0x00 0x00
> PortPwrCtrlMask 0xff 0xc3
> Hub Port Status:
> Port 1: 0000.0100 power
> Port 2: 0000.0100 power
> Port 3: 0000.0100 power
> Port 4: 0000.0100 power
> Port 5: 0000.0100 power
> Port 6: 0000.0100 power
> Port 7: 0000.0100 power
> Port 8: 0000.0100 power
> Port 9: 0000.0100 power
> Port 10: 0000.0100 power
> Device Status: 0x0003
> Self Powered
> Remote Wakeup Enabled
>
> Bus 001 Device 010: ID 0204:6025
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.00
> bDeviceClass 0 (Defined at Interface level)
> bDeviceSubClass 0
> bDeviceProtocol 0
> bMaxPacketSize0 64
> idVendor 0x0204
> idProduct 0x6025
> bcdDevice 1.00
> iManufacturer 1 ChipsBnk
> iProduct 2 Flash Disk
> iSerial 3 334011500461
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 32
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0x80
> (Bus Powered)
> MaxPower 100mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 2
> bInterfaceClass 8 Mass Storage
> bInterfaceSubClass 6 SCSI
> bInterfaceProtocol 80 Bulk (Zip)
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x01 EP 1 OUT
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0200 1x 512 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0200 1x 512 bytes
> bInterval 0
> Device Qualifier (for other device speed):
> bLength 10
> bDescriptorType 6
> bcdUSB 2.00
> bDeviceClass 0 (Defined at Interface level)
> bDeviceSubClass 0
> bDeviceProtocol 0
> bMaxPacketSize0 64
> bNumConfigurations 1
> Device Status: 0x0000
> (Bus Powered)
>
> Bus 001 Device 009: ID 0c45:613c Microdia
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 1.10
> bDeviceClass 0 (Defined at Interface level)
> bDeviceSubClass 0
> bDeviceProtocol 0
> bMaxPacketSize0 64
> idVendor 0x0c45 Microdia
> idProduct 0x613c
> bcdDevice 1.01
> iManufacturer 0
> iProduct 1 USB camera
> iSerial 0
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 279
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0x80
> (Bus Powered)
> MaxPower 100mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0000 1x 0 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 1
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0080 1x 128 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 2
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0100 1x 256 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 3
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0180 1x 384 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 4
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0200 1x 512 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 5
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x02a8 1x 680 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 6
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0320 1x 800 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 7
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0384 1x 900 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 8
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x03ff 1x 1023 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Device Status: 0x0000
> (Bus Powered)
>
> Bus 001 Device 006: ID 05e3:0606 Genesys Logic, Inc.
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.00
> bDeviceClass 9 Hub
> bDeviceSubClass 0 Unused
> bDeviceProtocol 1 Single TT
> bMaxPacketSize0 64
> idVendor 0x05e3 Genesys Logic, Inc.
> idProduct 0x0606
> bcdDevice 7.02
> iManufacturer 0
> iProduct 1 USB2.0 Hub
> iSerial 0
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 25
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0xe0
> Self Powered
> Remote Wakeup
> MaxPower 100mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 1
> bInterfaceClass 9 Hub
> bInterfaceSubClass 0 Unused
> bInterfaceProtocol 0 Full speed hub
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 12
> Hub Descriptor:
> bLength 9
> bDescriptorType 41
> nNbrPorts 4
> wHubCharacteristic 0x00e0
> Ganged power switching
> Ganged overcurrent protection
> TT think time 32 FS bits
> Port indicators
> bPwrOn2PwrGood 50 * 2 milli seconds
> bHubContrCurrent 100 milli Ampere
> DeviceRemovable 0x00
> PortPwrCtrlMask 0xff
> Hub Port Status:
> Port 1: 0000.0503 highspeed power enable connect
> Port 2: 0000.0100 power
> Port 3: 0000.0103 power enable connect
> Port 4: 0000.0100 power
> Device Qualifier (for other device speed):
> bLength 10
> bDescriptorType 6
> bcdUSB 2.00
> bDeviceClass 9 Hub
> bDeviceSubClass 0 Unused
> bDeviceProtocol 0 Full speed hub
> bMaxPacketSize0 64
> bNumConfigurations 1
> Device Status: 0x0003
> Self Powered
> Remote Wakeup Enabled
>
> Bus 001 Device 003: ID 05e3:0710 Genesys Logic, Inc. USB 2.0 33-in-1 Card
> Reader Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.00
> bDeviceClass 0 (Defined at Interface level)
> bDeviceSubClass 0
> bDeviceProtocol 0
> bMaxPacketSize0 64
> idVendor 0x05e3 Genesys Logic, Inc.
> idProduct 0x0710 USB 2.0 33-in-1 Card Reader
> bcdDevice 91.32
> iManufacturer 0
> iProduct 3 USB2.0 card Reader
> iSerial 4 00183
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 32
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0x80
> (Bus Powered)
> MaxPower 500mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 2
> bInterfaceClass 8 Mass Storage
> bInterfaceSubClass 6 SCSI
> bInterfaceProtocol 80 Bulk (Zip)
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0200 1x 512 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x02 EP 2 OUT
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0200 1x 512 bytes
> bInterval 0
> Device Qualifier (for other device speed):
> bLength 10
> bDescriptorType 6
> bcdUSB 2.00
> bDeviceClass 0 (Defined at Interface level)
> bDeviceSubClass 0
> bDeviceProtocol 0
> bMaxPacketSize0 64
> bNumConfigurations 1
> Device Status: 0x0000
> (Bus Powered)
>
> Bus 001 Device 001: ID 0000:0000
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.00
> bDeviceClass 9 Hub
> bDeviceSubClass 0 Unused
> bDeviceProtocol 1 Single TT
> bMaxPacketSize0 64
> idVendor 0x0000
> idProduct 0x0000
> bcdDevice 2.06
> iManufacturer 3 Linux 2.6.19.7-mb6 ehci_hcd
> iProduct 2 EHCI Host Controller
> iSerial 1 0000:00:02.1
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 25
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0xe0
> Self Powered
> Remote Wakeup
> MaxPower 0mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 1
> bInterfaceClass 9 Hub
> bInterfaceSubClass 0 Unused
> bInterfaceProtocol 0 Full speed hub
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0002 1x 2 bytes
> bInterval 12
> Hub Descriptor:
> bLength 11
> bDescriptorType 41
> nNbrPorts 10
> wHubCharacteristic 0x000a
> No power switching (usb 1.0)
> Per-port overcurrent protection
> TT think time 8 FS bits
> bPwrOn2PwrGood 10 * 2 milli seconds
> bHubContrCurrent 0 milli Ampere
> DeviceRemovable 0x00 0x00
> PortPwrCtrlMask 0xff 0xff
> Hub Port Status:
> Port 1: 0000.0100 power
> Port 2: 0000.0100 power
> Port 3: 0000.0100 power
> Port 4: 0000.0100 power
> Port 5: 0000.0100 power
> Port 6: 0000.0100 power
> Port 7: 0000.0503 highspeed power enable connect
> Port 8: 0000.0503 highspeed power enable connect
> Port 9: 0000.0100 power
> Port 10: 0000.0100 power
> Device Status: 0x0003
> Self Powered
> Remote Wakeup Enabled
--- lsusb -vv follows: only the camera, connected directly
> Bus 002 Device 004: ID 0c45:613c Microdia
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 1.10
> bDeviceClass 0 (Defined at Interface level)
> bDeviceSubClass 0
> bDeviceProtocol 0
> bMaxPacketSize0 64
> idVendor 0x0c45 Microdia
> idProduct 0x613c
> bcdDevice 1.01
> iManufacturer 0
> iProduct 1 USB camera
> iSerial 0
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 279
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0x80
> (Bus Powered)
> MaxPower 100mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0000 1x 0 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 1
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0080 1x 128 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 2
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0100 1x 256 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 3
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0180 1x 384 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 4
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0200 1x 512 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 5
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x02a8 1x 680 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 6
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0320 1x 800 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 7
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0384 1x 900 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 8
> bNumEndpoints 3
> bInterfaceClass 255 Vendor Specific Class
> bInterfaceSubClass 255 Vendor Specific Subclass
> bInterfaceProtocol 255 Vendor Specific Protocol
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 1
> Transfer Type Isochronous
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x03ff 1x 1023 bytes
> bInterval 1
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x82 EP 2 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0040 1x 64 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x83 EP 3 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0001 1x 1 bytes
> bInterval 100
> Device Status: 0x0000
> (Bus Powered)
>
> Bus 002 Device 001: ID 0000:0000
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 1.10
> bDeviceClass 9 Hub
> bDeviceSubClass 0 Unused
> bDeviceProtocol 0 Full speed hub
> bMaxPacketSize0 64
> idVendor 0x0000
> idProduct 0x0000
> bcdDevice 2.06
> iManufacturer 3 Linux 2.6.19.7-mb6 ohci_hcd
> iProduct 2 OHCI Host Controller
> iSerial 1 0000:00:02.0
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 25
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0xe0
> Self Powered
> Remote Wakeup
> MaxPower 0mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 1
> bInterfaceClass 9 Hub
> bInterfaceSubClass 0 Unused
> bInterfaceProtocol 0 Full speed hub
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0002 1x 2 bytes
> bInterval 255
> Hub Descriptor:
> bLength 11
> bDescriptorType 41
> nNbrPorts 10
> wHubCharacteristic 0x0002
> No power switching (usb 1.0)
> Ganged overcurrent protection
> bPwrOn2PwrGood 1 * 2 milli seconds
> bHubContrCurrent 0 milli Ampere
> DeviceRemovable 0x00 0x00
> PortPwrCtrlMask 0xff 0x85
> Hub Port Status:
> Port 1: 0000.0100 power
> Port 2: 0000.0100 power
> Port 3: 0000.0100 power
> Port 4: 0000.0100 power
> Port 5: 0000.0100 power
> Port 6: 0000.0100 power
> Port 7: 0000.0103 power enable connect
> Port 8: 0000.0100 power
> Port 9: 0000.0100 power
> Port 10: 0000.0100 power
> Device Status: 0x0003
> Self Powered
> Remote Wakeup Enabled
>
> Bus 001 Device 003: ID 05e3:0710 Genesys Logic, Inc. USB 2.0 33-in-1 Card
> Reader Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.00
> bDeviceClass 0 (Defined at Interface level)
> bDeviceSubClass 0
> bDeviceProtocol 0
> bMaxPacketSize0 64
> idVendor 0x05e3 Genesys Logic, Inc.
> idProduct 0x0710 USB 2.0 33-in-1 Card Reader
> bcdDevice 91.32
> iManufacturer 0
> iProduct 3 USB2.0 card Reader
> iSerial 4 00183
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 32
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0x80
> (Bus Powered)
> MaxPower 500mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 2
> bInterfaceClass 8 Mass Storage
> bInterfaceSubClass 6 SCSI
> bInterfaceProtocol 80 Bulk (Zip)
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0200 1x 512 bytes
> bInterval 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x02 EP 2 OUT
> bmAttributes 2
> Transfer Type Bulk
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0200 1x 512 bytes
> bInterval 0
> Device Qualifier (for other device speed):
> bLength 10
> bDescriptorType 6
> bcdUSB 2.00
> bDeviceClass 0 (Defined at Interface level)
> bDeviceSubClass 0
> bDeviceProtocol 0
> bMaxPacketSize0 64
> bNumConfigurations 1
> Device Status: 0x0000
> (Bus Powered)
>
> Bus 001 Device 001: ID 0000:0000
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.00
> bDeviceClass 9 Hub
> bDeviceSubClass 0 Unused
> bDeviceProtocol 1 Single TT
> bMaxPacketSize0 64
> idVendor 0x0000
> idProduct 0x0000
> bcdDevice 2.06
> iManufacturer 3 Linux 2.6.19.7-mb6 ehci_hcd
> iProduct 2 EHCI Host Controller
> iSerial 1 0000:00:02.1
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 25
> bNumInterfaces 1
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0xe0
> Self Powered
> Remote Wakeup
> MaxPower 0mA
> Interface Descriptor:
> bLength 9
> bDescriptorType 4
> bInterfaceNumber 0
> bAlternateSetting 0
> bNumEndpoints 1
> bInterfaceClass 9 Hub
> bInterfaceSubClass 0 Unused
> bInterfaceProtocol 0 Full speed hub
> iInterface 0
> Endpoint Descriptor:
> bLength 7
> bDescriptorType 5
> bEndpointAddress 0x81 EP 1 IN
> bmAttributes 3
> Transfer Type Interrupt
> Synch Type None
> Usage Type Data
> wMaxPacketSize 0x0002 1x 2 bytes
> bInterval 12
> Hub Descriptor:
> bLength 11
> bDescriptorType 41
> nNbrPorts 10
> wHubCharacteristic 0x000a
> No power switching (usb 1.0)
> Per-port overcurrent protection
> TT think time 8 FS bits
> bPwrOn2PwrGood 10 * 2 milli seconds
> bHubContrCurrent 0 milli Ampere
> DeviceRemovable 0x00 0x00
> PortPwrCtrlMask 0xff 0xff
> Hub Port Status:
> Port 1: 0000.0100 power
> Port 2: 0000.0100 power
> Port 3: 0000.0100 power
> Port 4: 0000.0100 power
> Port 5: 0000.0100 power
> Port 6: 0000.0100 power
> Port 7: 0000.0000
> Port 8: 0000.0503 highspeed power enable connect
> Port 9: 0000.0100 power
> Port 10: 0000.0100 power
> Device Status: 0x0003
> Self Powered
> Remote Wakeup Enabled
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: OHCI: USB webcam works, but not on USB Hub
[not found] <fa.R4OJEk76c3blNmi9oUs1xDRZGis@ifi.uio.no>
@ 2007-04-03 14:33 ` Robert Hancock
0 siblings, 0 replies; 5+ messages in thread
From: Robert Hancock @ 2007-04-03 14:33 UTC (permalink / raw)
To: Michael Bueker; +Cc: linux-kernel
Michael Bueker wrote:
> [please CC me on this thread]
>
> Hi everyone,
>
> My system has an nForce4 motherboard with an OHCI USB controller.
>
> I'm using a USB Webcam with the gspca driver (from
> http://mxhaard.free.fr/download.html), which has been working fine with the
> latest kernels.
>
> Today, I connected a USB Hub and the camera to it, after which it stopped
> working with the error message:
>> ERROR opening V4L interface
>> : Function not implemented
> However, it works fine when not connected to the Hub, but a motherboard's own
> USB port. The Hub also works fine with any other USB device.
>
> I googled around for a solution and found one for an older version of my
> driver, where the (apparently very ugly) fix was to manually set a fixed
> bandwidth for the USB device, instead of using a somehow other determined
> value. See this posting for a more elaborate description:
> http://lists.zerezo.com/spca50x-devs/msg00664.html
>
> Now, I'm writing to this list because one of the followups to that post
> (http://lists.zerezo.com/spca50x-devs/msg00665.html) states that this is due
> to a problem with the Linux USB layer:
>> pls file a bug "ohci driver can't handle low+fullspeed devices on the same
>> root hub" to linux usb devel list.
>
> That's about all I can tell you for now. I've attached two outputs of
> lsusb -vv, one with the hub attached, with the camera and a USB stick
> connected (notice the error message), and one without the hub and the
> camera connected directly (which is the setup where it works fine).
I looked into this at one point previously with spca5xx. Certainly in my
case it was no fault of the kernel. The isochronous descriptor that the
driver was deciding to use required so much bandwidth that it couldn't
be accomodated if anything else was using timeslots on the bus - even a
USB keyboard/mouse on the same hub would prevent it from getting enough
bandwidth.
Essentially the driver should fallback to a lower-bandwidth descriptor
if the one it tries to use fails rather than just bailing out.
--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: OHCI: USB webcam works, but not on USB Hub
@ 2007-04-03 14:41 Nicolas Mailhot
2007-04-03 15:22 ` Kok, Auke
0 siblings, 1 reply; 5+ messages in thread
From: Nicolas Mailhot @ 2007-04-03 14:41 UTC (permalink / raw)
To: linux-kernel, linux-usb-devel, video4linux-list; +Cc: Michael Bueker
Michael Bueker wrote :
> I'm using a USB Webcam with the gspca driver (from
> http://mxhaard.free.fr/download.html), which has been working fine with the
> latest kernels.
...
> Now, I'm writing to this list because one of the followups to that post
> (http://lists.zerezo.com/spca50x-devs/msg00665.html) states that this is
due
> to a problem with the Linux USB layer:
>> pls file a bug "ohci driver can't handle low+fullspeed devices on the same
>> root hub" to linux usb devel list.
Do the gspca driver authors even intend to merge their module in mainline
anytime soon? This kind of problem if typical of out-of-tree development.
--
Nicolas Mailhot
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: OHCI: USB webcam works, but not on USB Hub
2007-04-03 14:41 Nicolas Mailhot
@ 2007-04-03 15:22 ` Kok, Auke
2007-04-03 15:48 ` Pete Zaitcev
0 siblings, 1 reply; 5+ messages in thread
From: Kok, Auke @ 2007-04-03 15:22 UTC (permalink / raw)
To: Nicolas Mailhot
Cc: linux-kernel, linux-usb-devel, video4linux-list, Michael Bueker
Nicolas Mailhot wrote:
> Michael Bueker wrote :
>
>> I'm using a USB Webcam with the gspca driver (from
>> http://mxhaard.free.fr/download.html), which has been working fine with the
>> latest kernels.
>
> ...
>
>> Now, I'm writing to this list because one of the followups to that post
>> (http://lists.zerezo.com/spca50x-devs/msg00665.html) states that this is
> due
>> to a problem with the Linux USB layer:
>>> pls file a bug "ohci driver can't handle low+fullspeed devices on the same
>>> root hub" to linux usb devel list.
>
> Do the gspca driver authors even intend to merge their module in mainline
> anytime soon? This kind of problem if typical of out-of-tree development.
even plugging a gspca-device in a UHCI hub has issues - it doesn't work together
with any other device on the HUB the last time I checked.
Having the gspca driver move into the main tree would help a lot though.
Cheers,
Auke
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: OHCI: USB webcam works, but not on USB Hub
2007-04-03 15:22 ` Kok, Auke
@ 2007-04-03 15:48 ` Pete Zaitcev
0 siblings, 0 replies; 5+ messages in thread
From: Pete Zaitcev @ 2007-04-03 15:48 UTC (permalink / raw)
To: Kok, Auke
Cc: Nicolas Mailhot, video4linux-list, Michael Bueker, linux-kernel,
linux-usb-devel, zaitcev
On Tue, 03 Apr 2007 08:22:28 -0700, "Kok, Auke" <sofar@foo-projects.org> wrote:
> Having the gspca driver move into the main tree would help a lot though.
I think we need to articulate better why this is an issue and not just
an excuse. We know that scheduling issues with ISO transfers exist, but
with the driver outside we can't find a specific issue let alone fix it.
These things are hard to fix as it is.
For example, an external 2.0 hub with TT moves all transactions from OHCI
to EHCI, and adds an interrupt transfer which eats into your schedule.
I'm completely unsurprised that this fails. Wanna bet that Michael's
issue is something like that?
Another thing, requiring them to make the effort comes with an implicit
promise to fix whatever the user's problem is once they have moved gspca
in-tree. I'm not ready to tackle Michael's case, so I pretended not to
see his original mail.
-- Pete
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2007-04-03 15:49 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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[not found] <fa.R4OJEk76c3blNmi9oUs1xDRZGis@ifi.uio.no>
2007-04-03 14:33 ` OHCI: USB webcam works, but not on USB Hub Robert Hancock
2007-04-03 14:41 Nicolas Mailhot
2007-04-03 15:22 ` Kok, Auke
2007-04-03 15:48 ` Pete Zaitcev
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2007-04-03 12:02 Michael Bueker
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