kernel-ark/drivers/usb/host/xhci-plat.c
Sarah Sharp 52fb61250a xhci-plat: Don't enable legacy PCI interrupts.
The xHCI platform driver calls into usb_add_hcd to register the irq for
its platform device.  It does not want the xHCI generic driver to
register an interrupt for it at all.  The original code did that by
setting the XHCI_BROKEN_MSI quirk, which tells the xHCI driver to not
enable MSI or MSI-X for a PCI host.

Unfortunately, if CONFIG_PCI is enabled, and CONFIG_USB_DW3 is enabled,
the xHCI generic driver will attempt to register a legacy PCI interrupt
for the xHCI platform device in xhci_try_enable_msi().  This will result
in a bogus irq being registered, since the underlying device is a
platform_device, not a pci_device, and thus the pci_device->irq pointer
will be bogus.

Add a new quirk, XHCI_PLAT, so that the xHCI generic driver can
distinguish between a PCI device that can't handle MSI or MSI-X, and a
platform device that should not have its interrupts touched at all.
This quirk may be useful in the future, in case other corner cases like
this arise.

This patch should be backported to kernels as old as 3.9, that
contain the commit 00eed9c814 "USB: xhci:
correctly enable interrupts".

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Yu Y Wang <yu.y.wang@intel.com>
Tested-by: Yu Y Wang <yu.y.wang@intel.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Cc: stable@vger.kernel.org
2013-08-15 10:52:36 -07:00

207 lines
4.7 KiB
C

/*
* xhci-plat.c - xHCI host controller driver platform Bus Glue.
*
* Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com
* Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
*
* A lot of code borrowed from the Linux xHCI driver.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*/
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/slab.h>
#include "xhci.h"
static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci)
{
/*
* As of now platform drivers don't provide MSI support so we ensure
* here that the generic code does not try to make a pci_dev from our
* dev struct in order to setup MSI
*/
xhci->quirks |= XHCI_PLAT;
}
/* called during probe() after chip reset completes */
static int xhci_plat_setup(struct usb_hcd *hcd)
{
return xhci_gen_setup(hcd, xhci_plat_quirks);
}
static const struct hc_driver xhci_plat_xhci_driver = {
.description = "xhci-hcd",
.product_desc = "xHCI Host Controller",
.hcd_priv_size = sizeof(struct xhci_hcd *),
/*
* generic hardware linkage
*/
.irq = xhci_irq,
.flags = HCD_MEMORY | HCD_USB3 | HCD_SHARED,
/*
* basic lifecycle operations
*/
.reset = xhci_plat_setup,
.start = xhci_run,
.stop = xhci_stop,
.shutdown = xhci_shutdown,
/*
* managing i/o requests and associated device resources
*/
.urb_enqueue = xhci_urb_enqueue,
.urb_dequeue = xhci_urb_dequeue,
.alloc_dev = xhci_alloc_dev,
.free_dev = xhci_free_dev,
.alloc_streams = xhci_alloc_streams,
.free_streams = xhci_free_streams,
.add_endpoint = xhci_add_endpoint,
.drop_endpoint = xhci_drop_endpoint,
.endpoint_reset = xhci_endpoint_reset,
.check_bandwidth = xhci_check_bandwidth,
.reset_bandwidth = xhci_reset_bandwidth,
.address_device = xhci_address_device,
.update_hub_device = xhci_update_hub_device,
.reset_device = xhci_discover_or_reset_device,
/*
* scheduling support
*/
.get_frame_number = xhci_get_frame,
/* Root hub support */
.hub_control = xhci_hub_control,
.hub_status_data = xhci_hub_status_data,
.bus_suspend = xhci_bus_suspend,
.bus_resume = xhci_bus_resume,
};
static int xhci_plat_probe(struct platform_device *pdev)
{
const struct hc_driver *driver;
struct xhci_hcd *xhci;
struct resource *res;
struct usb_hcd *hcd;
int ret;
int irq;
if (usb_disabled())
return -ENODEV;
driver = &xhci_plat_xhci_driver;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return -ENODEV;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
if (!hcd)
return -ENOMEM;
hcd->rsrc_start = res->start;
hcd->rsrc_len = resource_size(res);
if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
driver->description)) {
dev_dbg(&pdev->dev, "controller already in use\n");
ret = -EBUSY;
goto put_hcd;
}
hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
if (!hcd->regs) {
dev_dbg(&pdev->dev, "error mapping memory\n");
ret = -EFAULT;
goto release_mem_region;
}
ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
if (ret)
goto unmap_registers;
/* USB 2.0 roothub is stored in the platform_device now. */
hcd = platform_get_drvdata(pdev);
xhci = hcd_to_xhci(hcd);
xhci->shared_hcd = usb_create_shared_hcd(driver, &pdev->dev,
dev_name(&pdev->dev), hcd);
if (!xhci->shared_hcd) {
ret = -ENOMEM;
goto dealloc_usb2_hcd;
}
/*
* Set the xHCI pointer before xhci_plat_setup() (aka hcd_driver.reset)
* is called by usb_add_hcd().
*/
*((struct xhci_hcd **) xhci->shared_hcd->hcd_priv) = xhci;
ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
if (ret)
goto put_usb3_hcd;
return 0;
put_usb3_hcd:
usb_put_hcd(xhci->shared_hcd);
dealloc_usb2_hcd:
usb_remove_hcd(hcd);
unmap_registers:
iounmap(hcd->regs);
release_mem_region:
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
put_hcd:
usb_put_hcd(hcd);
return ret;
}
static int xhci_plat_remove(struct platform_device *dev)
{
struct usb_hcd *hcd = platform_get_drvdata(dev);
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
usb_remove_hcd(xhci->shared_hcd);
usb_put_hcd(xhci->shared_hcd);
usb_remove_hcd(hcd);
iounmap(hcd->regs);
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
usb_put_hcd(hcd);
kfree(xhci);
return 0;
}
static struct platform_driver usb_xhci_driver = {
.probe = xhci_plat_probe,
.remove = xhci_plat_remove,
.driver = {
.name = "xhci-hcd",
},
};
MODULE_ALIAS("platform:xhci-hcd");
int xhci_register_plat(void)
{
return platform_driver_register(&usb_xhci_driver);
}
void xhci_unregister_plat(void)
{
platform_driver_unregister(&usb_xhci_driver);
}