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>

1 files changed, 0 insertions, 11 deletions

diff --git a/drivers/usb/host/u132-hcd.c b/drivers/usb/host/u132-hcd.c
index 20ad3c48fcb2..228f2b070f2b 100644
--- a/drivers/usb/host/u132-hcd.c
+++ b/drivers/usb/host/u132-hcd.c
@@ -2934,16 +2934,6 @@ static int u132_start_port_reset(struct usb_hcd *hcd, unsigned port_num)
                 return 0;
 }
 
-static void u132_hub_irq_enable(struct usb_hcd *hcd)
-{
-        struct u132 *u132 = hcd_to_u132(hcd);
-        if (u132->going > 1) {
-                dev_err(&u132->platform_dev->dev, "device has been removed %d\n"
-                        , u132->going);
-        } else if (u132->going > 0)
-                dev_err(&u132->platform_dev->dev, "device is being removed\n");
-}
-
 
 #ifdef CONFIG_PM
 static int u132_bus_suspend(struct usb_hcd *hcd)
@@ -2995,7 +2985,6 @@ static struct hc_driver u132_hc_driver = {
         .bus_suspend = u132_bus_suspend,
         .bus_resume = u132_bus_resume,
         .start_port_reset = u132_start_port_reset,
-        .hub_irq_enable = u132_hub_irq_enable,
 };
 
 /*