USB: don't explicitly reenable root-hub status interrupts
authorAlan Stern <stern@rowland.harvard.edu>
Mon, 14 Apr 2008 16:17:56 +0000 (12:17 -0400)
committerGreg Kroah-Hartman <gregkh@suse.de>
Fri, 25 Apr 2008 04:16:53 +0000 (21:16 -0700)
commite872154921a6b5256a3c412dd69158ac0b135176
tree65c1ef7054d7c5ed3a94799e09db8036a7f9574c
parent5f47493cdf90b8afe5353e59de30e449e775ea8b
USB: don't explicitly reenable root-hub status interrupts

This patch (as1069b) 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>
22 files changed:
drivers/usb/core/hcd.c
drivers/usb/core/hcd.h
drivers/usb/core/hub.c
drivers/usb/host/ohci-at91.c
drivers/usb/host/ohci-au1xxx.c
drivers/usb/host/ohci-ep93xx.c
drivers/usb/host/ohci-hub.c
drivers/usb/host/ohci-lh7a404.c
drivers/usb/host/ohci-omap.c
drivers/usb/host/ohci-pci.c
drivers/usb/host/ohci-pnx4008.c
drivers/usb/host/ohci-pnx8550.c
drivers/usb/host/ohci-ppc-of.c
drivers/usb/host/ohci-ppc-soc.c
drivers/usb/host/ohci-ps3.c
drivers/usb/host/ohci-pxa27x.c
drivers/usb/host/ohci-s3c2410.c
drivers/usb/host/ohci-sa1111.c
drivers/usb/host/ohci-sh.c
drivers/usb/host/ohci-sm501.c
drivers/usb/host/ohci-ssb.c
drivers/usb/host/u132-hcd.c