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linux/drivers/usb/host/ohci-ppc-of.c
Alan Stern b5fb454f69 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>
2008-08-21 10:26:38 -07:00

237 lines
4.9 KiB
C

/*
* OHCI HCD (Host Controller Driver) for USB.
*
* (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
* (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
* (C) Copyright 2002 Hewlett-Packard Company
* (C) Copyright 2006 Sylvain Munaut <tnt@246tNt.com>
*
* Bus glue for OHCI HC on the of_platform bus
*
* Modified for of_platform bus from ohci-sa1111.c
*
* This file is licenced under the GPL.
*/
#include <linux/signal.h>
#include <linux/of_platform.h>
#include <asm/prom.h>
static int __devinit
ohci_ppc_of_start(struct usb_hcd *hcd)
{
struct ohci_hcd *ohci = hcd_to_ohci(hcd);
int ret;
if ((ret = ohci_init(ohci)) < 0)
return ret;
if ((ret = ohci_run(ohci)) < 0) {
err("can't start %s", ohci_to_hcd(ohci)->self.bus_name);
ohci_stop(hcd);
return ret;
}
return 0;
}
static const struct hc_driver ohci_ppc_of_hc_driver = {
.description = hcd_name,
.product_desc = "OF OHCI",
.hcd_priv_size = sizeof(struct ohci_hcd),
/*
* generic hardware linkage
*/
.irq = ohci_irq,
.flags = HCD_USB11 | HCD_MEMORY,
/*
* basic lifecycle operations
*/
.start = ohci_ppc_of_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,
#ifdef CONFIG_PM
.bus_suspend = ohci_bus_suspend,
.bus_resume = ohci_bus_resume,
#endif
.start_port_reset = ohci_start_port_reset,
};
static int __devinit
ohci_hcd_ppc_of_probe(struct of_device *op, const struct of_device_id *match)
{
struct device_node *dn = op->node;
struct usb_hcd *hcd;
struct ohci_hcd *ohci;
struct resource res;
int irq;
int rv;
int is_bigendian;
if (usb_disabled())
return -ENODEV;
is_bigendian =
of_device_is_compatible(dn, "ohci-bigendian") ||
of_device_is_compatible(dn, "ohci-be");
dev_dbg(&op->dev, "initializing PPC-OF USB Controller\n");
rv = of_address_to_resource(dn, 0, &res);
if (rv)
return rv;
hcd = usb_create_hcd(&ohci_ppc_of_hc_driver, &op->dev, "PPC-OF USB");
if (!hcd)
return -ENOMEM;
hcd->rsrc_start = res.start;
hcd->rsrc_len = res.end - res.start + 1;
if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, hcd_name)) {
printk(KERN_ERR __FILE__ ": request_mem_region failed\n");
rv = -EBUSY;
goto err_rmr;
}
irq = irq_of_parse_and_map(dn, 0);
if (irq == NO_IRQ) {
printk(KERN_ERR __FILE__ ": irq_of_parse_and_map failed\n");
rv = -EBUSY;
goto err_irq;
}
hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
if (!hcd->regs) {
printk(KERN_ERR __FILE__ ": ioremap failed\n");
rv = -ENOMEM;
goto err_ioremap;
}
ohci = hcd_to_ohci(hcd);
if (is_bigendian) {
ohci->flags |= OHCI_QUIRK_BE_MMIO | OHCI_QUIRK_BE_DESC;
if (of_device_is_compatible(dn, "fsl,mpc5200-ohci"))
ohci->flags |= OHCI_QUIRK_FRAME_NO;
if (of_device_is_compatible(dn, "mpc5200-ohci"))
ohci->flags |= OHCI_QUIRK_FRAME_NO;
}
ohci_hcd_init(ohci);
rv = usb_add_hcd(hcd, irq, IRQF_DISABLED);
if (rv == 0)
return 0;
iounmap(hcd->regs);
err_ioremap:
irq_dispose_mapping(irq);
err_irq:
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
err_rmr:
usb_put_hcd(hcd);
return rv;
}
static int ohci_hcd_ppc_of_remove(struct of_device *op)
{
struct usb_hcd *hcd = dev_get_drvdata(&op->dev);
dev_set_drvdata(&op->dev, NULL);
dev_dbg(&op->dev, "stopping PPC-OF USB Controller\n");
usb_remove_hcd(hcd);
iounmap(hcd->regs);
irq_dispose_mapping(hcd->irq);
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
usb_put_hcd(hcd);
return 0;
}
static int ohci_hcd_ppc_of_shutdown(struct of_device *op)
{
struct usb_hcd *hcd = dev_get_drvdata(&op->dev);
if (hcd->driver->shutdown)
hcd->driver->shutdown(hcd);
return 0;
}
static struct of_device_id ohci_hcd_ppc_of_match[] = {
#ifdef CONFIG_USB_OHCI_HCD_PPC_OF_BE
{
.name = "usb",
.compatible = "ohci-bigendian",
},
{
.name = "usb",
.compatible = "ohci-be",
},
#endif
#ifdef CONFIG_USB_OHCI_HCD_PPC_OF_LE
{
.name = "usb",
.compatible = "ohci-littledian",
},
{
.name = "usb",
.compatible = "ohci-le",
},
#endif
{},
};
MODULE_DEVICE_TABLE(of, ohci_hcd_ppc_of_match);
#if !defined(CONFIG_USB_OHCI_HCD_PPC_OF_BE) && \
!defined(CONFIG_USB_OHCI_HCD_PPC_OF_LE)
#error "No endianess selected for ppc-of-ohci"
#endif
static struct of_platform_driver ohci_hcd_ppc_of_driver = {
.name = "ppc-of-ohci",
.match_table = ohci_hcd_ppc_of_match,
.probe = ohci_hcd_ppc_of_probe,
.remove = ohci_hcd_ppc_of_remove,
.shutdown = ohci_hcd_ppc_of_shutdown,
#ifdef CONFIG_PM
/*.suspend = ohci_hcd_ppc_soc_drv_suspend,*/
/*.resume = ohci_hcd_ppc_soc_drv_resume,*/
#endif
.driver = {
.name = "ppc-of-ohci",
.owner = THIS_MODULE,
},
};