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linux/drivers/usb/host/ehci-platform.c
Vivek Gautam e155b5b8d2 usb: ehci-platform: Return immediately from suspend if ehci_suspend fails
Patch 'b8efdaf USB: EHCI: add check for wakeup/suspend race'
adds a check for possible race between suspend and wakeup interrupt,
and thereby it returns -EBUSY as error code if there's a wakeup
interrupt.
So the platform host controller should not proceed further with
its suspend callback, rather should return immediately to avoid
powering down the essential things, like phy.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16 13:59:13 -07:00

391 lines
9.0 KiB
C

/*
* Generic platform ehci driver
*
* Copyright 2007 Steven Brown <sbrown@cortland.com>
* Copyright 2010-2012 Hauke Mehrtens <hauke@hauke-m.de>
* Copyright 2014 Hans de Goede <hdegoede@redhat.com>
*
* Derived from the ohci-ssb driver
* Copyright 2007 Michael Buesch <m@bues.ch>
*
* Derived from the EHCI-PCI driver
* Copyright (c) 2000-2004 by David Brownell
*
* Derived from the ohci-pci driver
* Copyright 1999 Roman Weissgaerber
* Copyright 2000-2002 David Brownell
* Copyright 1999 Linus Torvalds
* Copyright 1999 Gregory P. Smith
*
* Licensed under the GNU/GPL. See COPYING for details.
*/
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/hrtimer.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/usb/ehci_pdriver.h>
#include "ehci.h"
#define DRIVER_DESC "EHCI generic platform driver"
#define EHCI_MAX_CLKS 3
#define hcd_to_ehci_priv(h) ((struct ehci_platform_priv *)hcd_to_ehci(h)->priv)
struct ehci_platform_priv {
struct clk *clks[EHCI_MAX_CLKS];
struct phy *phy;
};
static const char hcd_name[] = "ehci-platform";
static int ehci_platform_reset(struct usb_hcd *hcd)
{
struct platform_device *pdev = to_platform_device(hcd->self.controller);
struct usb_ehci_pdata *pdata = dev_get_platdata(&pdev->dev);
struct ehci_hcd *ehci = hcd_to_ehci(hcd);
int retval;
hcd->has_tt = pdata->has_tt;
ehci->has_synopsys_hc_bug = pdata->has_synopsys_hc_bug;
if (pdata->pre_setup) {
retval = pdata->pre_setup(hcd);
if (retval < 0)
return retval;
}
ehci->caps = hcd->regs + pdata->caps_offset;
retval = ehci_setup(hcd);
if (retval)
return retval;
if (pdata->no_io_watchdog)
ehci->need_io_watchdog = 0;
return 0;
}
static int ehci_platform_power_on(struct platform_device *dev)
{
struct usb_hcd *hcd = platform_get_drvdata(dev);
struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
int clk, ret;
for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++) {
ret = clk_prepare_enable(priv->clks[clk]);
if (ret)
goto err_disable_clks;
}
if (priv->phy) {
ret = phy_init(priv->phy);
if (ret)
goto err_disable_clks;
ret = phy_power_on(priv->phy);
if (ret)
goto err_exit_phy;
}
return 0;
err_exit_phy:
phy_exit(priv->phy);
err_disable_clks:
while (--clk >= 0)
clk_disable_unprepare(priv->clks[clk]);
return ret;
}
static void ehci_platform_power_off(struct platform_device *dev)
{
struct usb_hcd *hcd = platform_get_drvdata(dev);
struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
int clk;
if (priv->phy) {
phy_power_off(priv->phy);
phy_exit(priv->phy);
}
for (clk = EHCI_MAX_CLKS - 1; clk >= 0; clk--)
if (priv->clks[clk])
clk_disable_unprepare(priv->clks[clk]);
}
static struct hc_driver __read_mostly ehci_platform_hc_driver;
static const struct ehci_driver_overrides platform_overrides __initconst = {
.reset = ehci_platform_reset,
.extra_priv_size = sizeof(struct ehci_platform_priv),
};
static struct usb_ehci_pdata ehci_platform_defaults = {
.power_on = ehci_platform_power_on,
.power_suspend = ehci_platform_power_off,
.power_off = ehci_platform_power_off,
};
static int ehci_platform_probe(struct platform_device *dev)
{
struct usb_hcd *hcd;
struct resource *res_mem;
struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
struct ehci_platform_priv *priv;
struct ehci_hcd *ehci;
int err, irq, clk = 0;
if (usb_disabled())
return -ENODEV;
/*
* Use reasonable defaults so platforms don't have to provide these
* with DT probing on ARM.
*/
if (!pdata)
pdata = &ehci_platform_defaults;
err = dma_coerce_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32));
if (err)
return err;
irq = platform_get_irq(dev, 0);
if (irq < 0) {
dev_err(&dev->dev, "no irq provided");
return irq;
}
res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
if (!res_mem) {
dev_err(&dev->dev, "no memory resource provided");
return -ENXIO;
}
hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
dev_name(&dev->dev));
if (!hcd)
return -ENOMEM;
platform_set_drvdata(dev, hcd);
dev->dev.platform_data = pdata;
priv = hcd_to_ehci_priv(hcd);
ehci = hcd_to_ehci(hcd);
if (pdata == &ehci_platform_defaults && dev->dev.of_node) {
if (of_property_read_bool(dev->dev.of_node, "big-endian-regs"))
ehci->big_endian_mmio = 1;
if (of_property_read_bool(dev->dev.of_node, "big-endian-desc"))
ehci->big_endian_desc = 1;
if (of_property_read_bool(dev->dev.of_node, "big-endian"))
ehci->big_endian_mmio = ehci->big_endian_desc = 1;
priv->phy = devm_phy_get(&dev->dev, "usb");
if (IS_ERR(priv->phy)) {
err = PTR_ERR(priv->phy);
if (err == -EPROBE_DEFER)
goto err_put_hcd;
priv->phy = NULL;
}
for (clk = 0; clk < EHCI_MAX_CLKS; clk++) {
priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
if (IS_ERR(priv->clks[clk])) {
err = PTR_ERR(priv->clks[clk]);
if (err == -EPROBE_DEFER)
goto err_put_clks;
priv->clks[clk] = NULL;
break;
}
}
}
if (pdata->big_endian_desc)
ehci->big_endian_desc = 1;
if (pdata->big_endian_mmio)
ehci->big_endian_mmio = 1;
#ifndef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
if (ehci->big_endian_mmio) {
dev_err(&dev->dev,
"Error: CONFIG_USB_EHCI_BIG_ENDIAN_MMIO not set\n");
err = -EINVAL;
goto err_put_clks;
}
#endif
#ifndef CONFIG_USB_EHCI_BIG_ENDIAN_DESC
if (ehci->big_endian_desc) {
dev_err(&dev->dev,
"Error: CONFIG_USB_EHCI_BIG_ENDIAN_DESC not set\n");
err = -EINVAL;
goto err_put_clks;
}
#endif
if (pdata->power_on) {
err = pdata->power_on(dev);
if (err < 0)
goto err_put_clks;
}
hcd->rsrc_start = res_mem->start;
hcd->rsrc_len = resource_size(res_mem);
hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
if (IS_ERR(hcd->regs)) {
err = PTR_ERR(hcd->regs);
goto err_power;
}
err = usb_add_hcd(hcd, irq, IRQF_SHARED);
if (err)
goto err_power;
device_wakeup_enable(hcd->self.controller);
platform_set_drvdata(dev, hcd);
return err;
err_power:
if (pdata->power_off)
pdata->power_off(dev);
err_put_clks:
while (--clk >= 0)
clk_put(priv->clks[clk]);
err_put_hcd:
if (pdata == &ehci_platform_defaults)
dev->dev.platform_data = NULL;
usb_put_hcd(hcd);
return err;
}
static int ehci_platform_remove(struct platform_device *dev)
{
struct usb_hcd *hcd = platform_get_drvdata(dev);
struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
int clk;
usb_remove_hcd(hcd);
if (pdata->power_off)
pdata->power_off(dev);
for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++)
clk_put(priv->clks[clk]);
usb_put_hcd(hcd);
if (pdata == &ehci_platform_defaults)
dev->dev.platform_data = NULL;
return 0;
}
#ifdef CONFIG_PM
static int ehci_platform_suspend(struct device *dev)
{
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
struct platform_device *pdev =
container_of(dev, struct platform_device, dev);
bool do_wakeup = device_may_wakeup(dev);
int ret;
ret = ehci_suspend(hcd, do_wakeup);
if (ret)
return ret;
if (pdata->power_suspend)
pdata->power_suspend(pdev);
return ret;
}
static int ehci_platform_resume(struct device *dev)
{
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
struct platform_device *pdev =
container_of(dev, struct platform_device, dev);
if (pdata->power_on) {
int err = pdata->power_on(pdev);
if (err < 0)
return err;
}
ehci_resume(hcd, false);
return 0;
}
#else /* !CONFIG_PM */
#define ehci_platform_suspend NULL
#define ehci_platform_resume NULL
#endif /* CONFIG_PM */
static const struct of_device_id vt8500_ehci_ids[] = {
{ .compatible = "via,vt8500-ehci", },
{ .compatible = "wm,prizm-ehci", },
{ .compatible = "generic-ehci", },
{}
};
MODULE_DEVICE_TABLE(of, vt8500_ehci_ids);
static const struct platform_device_id ehci_platform_table[] = {
{ "ehci-platform", 0 },
{ }
};
MODULE_DEVICE_TABLE(platform, ehci_platform_table);
static const struct dev_pm_ops ehci_platform_pm_ops = {
.suspend = ehci_platform_suspend,
.resume = ehci_platform_resume,
};
static struct platform_driver ehci_platform_driver = {
.id_table = ehci_platform_table,
.probe = ehci_platform_probe,
.remove = ehci_platform_remove,
.shutdown = usb_hcd_platform_shutdown,
.driver = {
.owner = THIS_MODULE,
.name = "ehci-platform",
.pm = &ehci_platform_pm_ops,
.of_match_table = vt8500_ehci_ids,
}
};
static int __init ehci_platform_init(void)
{
if (usb_disabled())
return -ENODEV;
pr_info("%s: " DRIVER_DESC "\n", hcd_name);
ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
return platform_driver_register(&ehci_platform_driver);
}
module_init(ehci_platform_init);
static void __exit ehci_platform_cleanup(void)
{
platform_driver_unregister(&ehci_platform_driver);
}
module_exit(ehci_platform_cleanup);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Hauke Mehrtens");
MODULE_AUTHOR("Alan Stern");
MODULE_LICENSE("GPL");