Hi Alan: 2009/10/8 Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>: > On Thu, 8 Oct 2009, vichy wrote: > >> Dear all: >> I am looking the source code of ehci-irq, but I cannot see any >> information which it will pass to "port_connect_change" when it >> receive PCD interrupt. >> if someone is familiar with this part of flow, please let me know. >> appreciate your help, > > When ehci_irq() receives a PCD interrupt, it sets pcd_status and > therefore calls usb_hcd_poll_rh_status(). That routine calls > ehci_hub_status_data(), which reads the port status registers from the > controller. The value is masked with PORT_CSC (Connect Status Change) > causing a bit to be set in buf[0] or buf[1]. This bit tells the hub > driver that a status change has occurred. > Thanks for your kind help :) I did see what you mention in source code. But the mechanism seems different in older version driver, which ehci-irq doesn't set any flag but later time I can see someone wake up hub driver to continue. appreciate your help, vichy -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
