USB device question - Linux

This is a discussion on USB device question - Linux ; Hi, I am debugging s3c2410's usb device driver for linux, I have connect the VCC, GND, D+, D- and the usb device end can detect the insert/plug of usb cable. I installed a IRQ handler for the usb device and ...

+ Reply to Thread
Results 1 to 4 of 4

Thread: USB device question

  1. USB device question

    Hi,

    I am debugging s3c2410's usb device driver for linux, I have connect
    the VCC, GND, D+, D- and the usb device end can detect the insert/plug
    of usb cable. I installed a IRQ handler for the usb device and it can
    recieve some interrupt of reset when I insert the USB to host.

    But after the reset, no further interrupt happen. Even in the host
    side there are nothing displayed. I want to know how can I debug it?

    According the USB spec, after the HOST hub send Reset to device, the
    device need to pull up/down a data line to indicate the existence of
    the device, can I measure this signal on the four lines? Which line
    should I measure?

    I think the host didn't begin to enumerate the device because the
    device didn't send ACK of the reset to indicate the attach.

    Thanks.
    Bin


  2. Re: USB device question

    On Nov 2, 4:49 pm, Bin Chen wrote:
    > Hi,
    >
    > I am debugging s3c2410's usb device driver for linux, I have connect
    > the VCC, GND, D+, D- and the usb device end can detect the insert/plug
    > of usb cable. I installed a IRQ handler for the usb device and it can
    > recieve some interrupt of reset when I insert the USB to host.
    >
    > But after the reset, no further interrupt happen. Even in the host
    > side there are nothing displayed. I want to know how can I debug it?
    >
    > According the USB spec, after the HOST hub send Reset to device, the
    > device need to pull up/down a data line to indicate the existence of
    > the device, can I measure this signal on the four lines? Which line
    > should I measure?
    >
    > I think the host didn't begin to enumerate the device because the
    > device didn't send ACK of the reset to indicate the attach.
    >


    Which version of USB are you using ? USB 1.1/USB 2.0.

    Karthik Balaguru


  3. Re: USB device question

    Bin Chen wrote:

    >Hi,
    >
    >I am debugging s3c2410's usb device driver for linux, I have connect
    >the VCC, GND, D+, D- and the usb device end can detect the insert/plug
    >of usb cable. I installed a IRQ handler for the usb device and it can
    >recieve some interrupt of reset when I insert the USB to host.
    >
    >But after the reset, no further interrupt happen. Even in the host
    >side there are nothing displayed. I want to know how can I debug it?
    >
    >According the USB spec, after the HOST hub send Reset to device, the
    >device need to pull up/down a data line to indicate the existence of
    >the device, can I measure this signal on the four lines? Which line
    >should I measure?
    >
    >I think the host didn't begin to enumerate the device because the
    >device didn't send ACK of the reset to indicate the attach.


    There are flow charts in appendix C of the USB spec that show the reset
    handling, and the text is in section 7.1.7.5.
    --
    Tim Roberts, timr@probo.com
    Providenza & Boekelheide, Inc.

  4. Re: USB device question

    On 11 4 , 2 23 , karthikbalaguru
    wrote:
    > On Nov 2, 4:49 pm, Bin Chen wrote:
    >
    >
    >
    > > Hi,

    >
    > > I am debugging s3c2410's usb device driver for linux, I have connect
    > > the VCC, GND, D+, D- and the usb device end can detect the insert/plug
    > > of usb cable. I installed a IRQ handler for the usb device and it can
    > > recieve some interrupt of reset when I insert the USB to host.

    >
    > > But after the reset, no further interrupt happen. Even in the host
    > > side there are nothing displayed. I want to know how can I debug it?

    >
    > > According the USB spec, after the HOST hub send Reset to device, the
    > > device need to pull up/down a data line to indicate the existence of
    > > the device, can I measure this signal on the four lines? Which line
    > > should I measure?

    >
    > > I think the host didn't begin to enumerate the device because the
    > > device didn't send ACK of the reset to indicate the attach.

    >
    > Which version of USB are you using ? USB 1.1/USB 2.0.
    >

    1.1



+ Reply to Thread