tree aa68acda039477c8d6411ed3e0fe78d3f9098071
parent 5096aedcd2eb70fbea83f09281f97f9ec973d9de
author Alan Stern <stern@rowland.harvard.edu> 1219267325 -0400
committer Greg Kroah-Hartman <gregkh@suse.de> 1219339598 -0700

USB: automatically enable RHSC interrupts

This patch (as1069c) changes the way OHCI root-hub status-change
interrupts are enabled.  Currently a special HCD method,
hub_irq_enable(), is called when the hub driver is finished using a
root hub.  This approach turns out to be subject to races, resulting
in unnecessary polling.

The patch does away with the method entirely.  Instead, the driver
automatically enables the RHSC interrupt when no more status changes
are present.  This scheme is safe with controllers using
level-triggered semantics for their interrupt flags.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>