On Mon, 19 Mar 2012, Lan Tianyu wrote: > Add struct usb_hub_port pointer port_data in the struct usb_hub and allocate > struct usb_hub_port perspectively for each ports to store private data. You might as well add the child device pointer into your new data structure. This will require changes to at least three other files in addition to hub.c: devices.c, host/r8a66597-hcd.c, drivers/staging/usbip/usbip_common.c Maybe some others; I didn't look through the entire kernel source. It also means you will have to export a function to get a pointer to the child device, given the port number. > @@ -1451,13 +1456,12 @@ void usb_hub_release_all_ports(struct usb_device *hdev, void *owner) > int n; > void **powner; > > - n = find_port_owner(hdev, 1, &powner); > - if (n == 0) { > - for (; n < hdev->maxchild; (++n, ++powner)) { > - if (*powner == owner) > - *powner = NULL; > - } > + for (n = 1; n <= hdev->maxchild; n++) { > + find_port_owner(hdev, n, &powner); > + if (*powner == owner) > + *powner = NULL; > } This is wrong; find_port_owner() doesn't set powner to anything if an error occurs. You can just set the pointer field directly to NULL, instead of looking it up in find_port_owner(). I don't remember why it was written that way originally. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html