linux/drivers/usb/host/ohci-sh.c
Linus Torvalds 09ca8adbe9 Revert "USB: don't explicitly reenable root-hub status interrupts"
This reverts commit e872154921.

Andrey Borzenkov reports that it resulted in a totally hung machine for
him when loading the OHCI driver.  Extensive netconsole capture with
SysRq output shows that modprobe gets stuck in ohci_hub_status_data()
when probing and enabling the OHCI controller, see for example

	http://lkml.org/lkml/2008/7/5/236

for an analysis.

The problem appears to be an interrupt flood triggered by the commit
that gets reverted, and Andrey confirmed that the revert makes things
work for him again.

Reported-and-tested-by: Andrey Borzenkov <arvidjaar@mail.ru>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <david-b@pacbell.net>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-06 10:27:25 -07:00

145 lines
3.3 KiB
C

/*
* OHCI HCD (Host Controller Driver) for USB.
*
* Copyright (C) 2008 Renesas Solutions Corp.
*
* Author : Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <linux/platform_device.h>
static int ohci_sh_start(struct usb_hcd *hcd)
{
struct ohci_hcd *ohci = hcd_to_ohci(hcd);
ohci_hcd_init(ohci);
ohci_init(ohci);
ohci_run(ohci);
hcd->state = HC_STATE_RUNNING;
return 0;
}
static const struct hc_driver ohci_sh_hc_driver = {
.description = hcd_name,
.product_desc = "SuperH OHCI",
.hcd_priv_size = sizeof(struct ohci_hcd),
/*
* generic hardware linkage
*/
.irq = ohci_irq,
.flags = HCD_USB11 | HCD_MEMORY,
/*
* basic lifecycle operations
*/
.start = ohci_sh_start,
.stop = ohci_stop,
.shutdown = ohci_shutdown,
/*
* managing i/o requests and associated device resources
*/
.urb_enqueue = ohci_urb_enqueue,
.urb_dequeue = ohci_urb_dequeue,
.endpoint_disable = ohci_endpoint_disable,
/*
* scheduling support
*/
.get_frame_number = ohci_get_frame,
/*
* root hub support
*/
.hub_status_data = ohci_hub_status_data,
.hub_control = ohci_hub_control,
.hub_irq_enable = ohci_rhsc_enable,
#ifdef CONFIG_PM
.bus_suspend = ohci_bus_suspend,
.bus_resume = ohci_bus_resume,
#endif
.start_port_reset = ohci_start_port_reset,
};
/*-------------------------------------------------------------------------*/
#define resource_len(r) (((r)->end - (r)->start) + 1)
static int ohci_hcd_sh_probe(struct platform_device *pdev)
{
struct resource *res = NULL;
struct usb_hcd *hcd = NULL;
int irq = -1;
int ret;
if (usb_disabled())
return -ENODEV;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
err("platform_get_resource error.");
return -ENODEV;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
err("platform_get_irq error.");
return -ENODEV;
}
/* initialize hcd */
hcd = usb_create_hcd(&ohci_sh_hc_driver, &pdev->dev, (char *)hcd_name);
if (!hcd) {
err("Failed to create hcd");
return -ENOMEM;
}
hcd->regs = (void __iomem *)res->start;
hcd->rsrc_start = res->start;
hcd->rsrc_len = resource_len(res);
ret = usb_add_hcd(hcd, irq, IRQF_DISABLED);
if (ret != 0) {
err("Failed to add hcd");
usb_put_hcd(hcd);
return ret;
}
return ret;
}
static int ohci_hcd_sh_remove(struct platform_device *pdev)
{
struct usb_hcd *hcd = platform_get_drvdata(pdev);
usb_remove_hcd(hcd);
usb_put_hcd(hcd);
return 0;
}
static struct platform_driver ohci_hcd_sh_driver = {
.probe = ohci_hcd_sh_probe,
.remove = ohci_hcd_sh_remove,
.shutdown = usb_hcd_platform_shutdown,
.driver = {
.name = "sh_ohci",
.owner = THIS_MODULE,
},
};
MODULE_ALIAS("platform:sh_ohci");