1
linux/drivers/usb/host/ohci-ssb.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

215 lines
4.7 KiB
C

/*
* Sonics Silicon Backplane
* Broadcom USB-core OHCI driver
*
* Copyright 2007 Michael Buesch <mb@bu3sch.de>
*
* Derived from the OHCI-PCI driver
* Copyright 1999 Roman Weissgaerber
* Copyright 2000-2002 David Brownell
* Copyright 1999 Linus Torvalds
* Copyright 1999 Gregory P. Smith
*
* Derived from the USBcore related parts of Broadcom-SB
* Copyright 2005 Broadcom Corporation
*
* Licensed under the GNU/GPL. See COPYING for details.
*/
#include <linux/ssb/ssb.h>
#define SSB_OHCI_TMSLOW_HOSTMODE (1 << 29)
struct ssb_ohci_device {
struct ohci_hcd ohci; /* _must_ be at the beginning. */
u32 enable_flags;
};
static inline
struct ssb_ohci_device *hcd_to_ssb_ohci(struct usb_hcd *hcd)
{
return (struct ssb_ohci_device *)(hcd->hcd_priv);
}
static int ssb_ohci_reset(struct usb_hcd *hcd)
{
struct ssb_ohci_device *ohcidev = hcd_to_ssb_ohci(hcd);
struct ohci_hcd *ohci = &ohcidev->ohci;
int err;
ohci_hcd_init(ohci);
err = ohci_init(ohci);
return err;
}
static int ssb_ohci_start(struct usb_hcd *hcd)
{
struct ssb_ohci_device *ohcidev = hcd_to_ssb_ohci(hcd);
struct ohci_hcd *ohci = &ohcidev->ohci;
int err;
err = ohci_run(ohci);
if (err < 0) {
ohci_err(ohci, "can't start\n");
ohci_stop(hcd);
}
return err;
}
static const struct hc_driver ssb_ohci_hc_driver = {
.description = "ssb-usb-ohci",
.product_desc = "SSB OHCI Controller",
.hcd_priv_size = sizeof(struct ssb_ohci_device),
.irq = ohci_irq,
.flags = HCD_MEMORY | HCD_USB11,
.reset = ssb_ohci_reset,
.start = ssb_ohci_start,
.stop = ohci_stop,
.shutdown = ohci_shutdown,
.urb_enqueue = ohci_urb_enqueue,
.urb_dequeue = ohci_urb_dequeue,
.endpoint_disable = ohci_endpoint_disable,
.get_frame_number = ohci_get_frame,
.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 void ssb_ohci_detach(struct ssb_device *dev)
{
struct usb_hcd *hcd = ssb_get_drvdata(dev);
usb_remove_hcd(hcd);
iounmap(hcd->regs);
usb_put_hcd(hcd);
ssb_device_disable(dev, 0);
}
static int ssb_ohci_attach(struct ssb_device *dev)
{
struct ssb_ohci_device *ohcidev;
struct usb_hcd *hcd;
int err = -ENOMEM;
u32 tmp, flags = 0;
if (dev->id.coreid == SSB_DEV_USB11_HOSTDEV)
flags |= SSB_OHCI_TMSLOW_HOSTMODE;
ssb_device_enable(dev, flags);
hcd = usb_create_hcd(&ssb_ohci_hc_driver, dev->dev,
dev_name(dev->dev));
if (!hcd)
goto err_dev_disable;
ohcidev = hcd_to_ssb_ohci(hcd);
ohcidev->enable_flags = flags;
tmp = ssb_read32(dev, SSB_ADMATCH0);
hcd->rsrc_start = ssb_admatch_base(tmp);
hcd->rsrc_len = ssb_admatch_size(tmp);
hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
if (!hcd->regs)
goto err_put_hcd;
err = usb_add_hcd(hcd, dev->irq, IRQF_DISABLED | IRQF_SHARED);
if (err)
goto err_iounmap;
ssb_set_drvdata(dev, hcd);
return err;
err_iounmap:
iounmap(hcd->regs);
err_put_hcd:
usb_put_hcd(hcd);
err_dev_disable:
ssb_device_disable(dev, flags);
return err;
}
static int ssb_ohci_probe(struct ssb_device *dev,
const struct ssb_device_id *id)
{
int err;
u16 chipid_top;
/* USBcores are only connected on embedded devices. */
chipid_top = (dev->bus->chip_id & 0xFF00);
if (chipid_top != 0x4700 && chipid_top != 0x5300)
return -ENODEV;
/* TODO: Probably need checks here; is the core connected? */
if (usb_disabled())
return -ENODEV;
/* We currently always attach SSB_DEV_USB11_HOSTDEV
* as HOST OHCI. If we want to attach it as Client device,
* we must branch here and call into the (yet to
* be written) Client mode driver. Same for remove(). */
err = ssb_ohci_attach(dev);
return err;
}
static void ssb_ohci_remove(struct ssb_device *dev)
{
ssb_ohci_detach(dev);
}
#ifdef CONFIG_PM
static int ssb_ohci_suspend(struct ssb_device *dev, pm_message_t state)
{
ssb_device_disable(dev, 0);
return 0;
}
static int ssb_ohci_resume(struct ssb_device *dev)
{
struct usb_hcd *hcd = ssb_get_drvdata(dev);
struct ssb_ohci_device *ohcidev = hcd_to_ssb_ohci(hcd);
ssb_device_enable(dev, ohcidev->enable_flags);
ohci_finish_controller_resume(hcd);
return 0;
}
#else /* !CONFIG_PM */
#define ssb_ohci_suspend NULL
#define ssb_ohci_resume NULL
#endif /* CONFIG_PM */
static const struct ssb_device_id ssb_ohci_table[] = {
SSB_DEVICE(SSB_VENDOR_BROADCOM, SSB_DEV_USB11_HOSTDEV, SSB_ANY_REV),
SSB_DEVICE(SSB_VENDOR_BROADCOM, SSB_DEV_USB11_HOST, SSB_ANY_REV),
SSB_DEVTABLE_END
};
MODULE_DEVICE_TABLE(ssb, ssb_ohci_table);
static struct ssb_driver ssb_ohci_driver = {
.name = KBUILD_MODNAME,
.id_table = ssb_ohci_table,
.probe = ssb_ohci_probe,
.remove = ssb_ohci_remove,
.suspend = ssb_ohci_suspend,
.resume = ssb_ohci_resume,
};