Re: Full speed device support for dwc_otg host controller.

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Hello Alan,


On 5/28/2012 8:55 PM, Alan Stern wrote:
2. Is there any flag available which will solve my limitation ? (start
>  supporting full speed as well as high speed)
This has nothing to do with flags.  Adding a flag to your driver won't
magically enable it to handle full speed communications.


Just for curiosity,
I have passed USB1 from this flag and it starts supporting full speed device.

When I passed USB2 flag from this and connect a full speed hub, it reflect "parent hub has no TT". The print is coming from

 /* Set up TT records, if needed  */
        if (hdev->tt) {
                udev->tt = hdev->tt;
                udev->ttport = hdev->ttport;
        } else if (udev->speed != USB_SPEED_HIGH
                        && hdev->speed == USB_SPEED_HIGH) {
                if (!hub->tt.hub) {
                        dev_err(&udev->dev, "parent hub has no TT\n");
                        retval = -EINVAL;
                        goto fail;
                }
	}
My debugging says that
1. hdev->speed == USB_SPEED_HIGH comparison is true, but why when I am attaching a full speed device.

2. The print "parent hub has no TT\n" will only come when there is no tt.hub. Now this is only possible when hdev->descriptor.bDeviceProtocol == 0. Could you please guide me from where this field is getting updated?

Best Regards
Rajeev






Alan Stern

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