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Dear All, We are looking into the EHCI driver source code in Linux
kernel 2.6.14 version. Actually we want to know the function flow at the time
of the device connection (i.e. at the time of enumeration phase). For this, we built
the Linux image by including the debug statements through printks in EHCI
related files in Linux source code (drivers/usb/host). We found that the
ehci_start callback method is invoked from usb_hcd_pci_probe method at the time
of initialization (when we run modprobe / insmod command). The same we tried to
know the name of the method which invokes the ehci_urb_enqueue callback method
of the EHCI. We have noticed the following function flow in the
/var/log/messages file / through dmesg command after inserting the device into
a USB port. ehci_urb_enqueueàqh_urb_transaction
à qtd_fill àsubmit async à qtd_append_tds à qh_link_async. We have also noticed that qh_link_async moves filled qheads
into asynchronous list by writing the command into the EHCI operational
register’s command register. We are not able to find the function name that which invokes
the ehci_urb_enqueue method. So, could any one please tell/suggest us the
function name OR procedure to find out. Thanks and Regards, Srinivas G |
