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linux-next/drivers/usb/host/xhci-mtk.c
Mathias Nyman f068090426 xhci: Fix leaking USB3 shared_hcd at xhci removal
Ensure that the shared_hcd pointer is valid when calling usb_put_hcd()

The shared_hcd is removed and freed in xhci by first calling
usb_remove_hcd(xhci->shared_hcd), and later
usb_put_hcd(xhci->shared_hcd)

Afer commit fe190ed0d6 ("xhci: Do not halt the host until both HCD have
disconnected their devices.") the shared_hcd was never properly put as
xhci->shared_hcd was set to NULL before usb_put_hcd(xhci->shared_hcd) was
called.

shared_hcd (USB3) is removed before primary hcd (USB2).
While removing the primary hcd we might need to handle xhci interrupts
to cleanly remove last USB2 devices, therefore we need to set
xhci->shared_hcd to NULL before removing the primary hcd to let xhci
interrupt handler know shared_hcd is no longer available.

xhci-plat.c, xhci-histb.c and xhci-mtk first create both their hcd's before
adding them. so to keep the correct reverse removal order use a temporary
shared_hcd variable for them.
For more details see commit 4ac53087d6 ("usb: xhci: plat: Create both
HCDs before adding them")

Fixes: fe190ed0d6 ("xhci: Do not halt the host until both HCD have disconnected their devices.")
Cc: Joel Stanley <joel@jms.id.au>
Cc: Chunfeng Yun <chunfeng.yun@mediatek.com>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Jianguo Sun <sunjianguo1@huawei.com>
Cc: <stable@vger.kernel.org>
Reported-by: Jack Pham <jackp@codeaurora.org>
Tested-by: Jack Pham <jackp@codeaurora.org>
Tested-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09 08:31:08 -08:00

695 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* MediaTek xHCI Host Controller Driver
*
* Copyright (c) 2015 MediaTek Inc.
* Author:
* Chunfeng Yun <chunfeng.yun@mediatek.com>
*/
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include "xhci.h"
#include "xhci-mtk.h"
/* ip_pw_ctrl0 register */
#define CTRL0_IP_SW_RST BIT(0)
/* ip_pw_ctrl1 register */
#define CTRL1_IP_HOST_PDN BIT(0)
/* ip_pw_ctrl2 register */
#define CTRL2_IP_DEV_PDN BIT(0)
/* ip_pw_sts1 register */
#define STS1_IP_SLEEP_STS BIT(30)
#define STS1_U3_MAC_RST BIT(16)
#define STS1_XHCI_RST BIT(11)
#define STS1_SYS125_RST BIT(10)
#define STS1_REF_RST BIT(8)
#define STS1_SYSPLL_STABLE BIT(0)
/* ip_xhci_cap register */
#define CAP_U3_PORT_NUM(p) ((p) & 0xff)
#define CAP_U2_PORT_NUM(p) (((p) >> 8) & 0xff)
/* u3_ctrl_p register */
#define CTRL_U3_PORT_HOST_SEL BIT(2)
#define CTRL_U3_PORT_PDN BIT(1)
#define CTRL_U3_PORT_DIS BIT(0)
/* u2_ctrl_p register */
#define CTRL_U2_PORT_HOST_SEL BIT(2)
#define CTRL_U2_PORT_PDN BIT(1)
#define CTRL_U2_PORT_DIS BIT(0)
/* u2_phy_pll register */
#define CTRL_U2_FORCE_PLL_STB BIT(28)
/* usb remote wakeup registers in syscon */
/* mt8173 etc */
#define PERI_WK_CTRL1 0x4
#define WC1_IS_C(x) (((x) & 0xf) << 26) /* cycle debounce */
#define WC1_IS_EN BIT(25)
#define WC1_IS_P BIT(6) /* polarity for ip sleep */
/* mt2712 etc */
#define PERI_SSUSB_SPM_CTRL 0x0
#define SSC_IP_SLEEP_EN BIT(4)
#define SSC_SPM_INT_EN BIT(1)
enum ssusb_uwk_vers {
SSUSB_UWK_V1 = 1,
SSUSB_UWK_V2,
};
static int xhci_mtk_host_enable(struct xhci_hcd_mtk *mtk)
{
struct mu3c_ippc_regs __iomem *ippc = mtk->ippc_regs;
u32 value, check_val;
int u3_ports_disabed = 0;
int ret;
int i;
if (!mtk->has_ippc)
return 0;
/* power on host ip */
value = readl(&ippc->ip_pw_ctr1);
value &= ~CTRL1_IP_HOST_PDN;
writel(value, &ippc->ip_pw_ctr1);
/* power on and enable u3 ports except skipped ones */
for (i = 0; i < mtk->num_u3_ports; i++) {
if ((0x1 << i) & mtk->u3p_dis_msk) {
u3_ports_disabed++;
continue;
}
value = readl(&ippc->u3_ctrl_p[i]);
value &= ~(CTRL_U3_PORT_PDN | CTRL_U3_PORT_DIS);
value |= CTRL_U3_PORT_HOST_SEL;
writel(value, &ippc->u3_ctrl_p[i]);
}
/* power on and enable all u2 ports */
for (i = 0; i < mtk->num_u2_ports; i++) {
value = readl(&ippc->u2_ctrl_p[i]);
value &= ~(CTRL_U2_PORT_PDN | CTRL_U2_PORT_DIS);
value |= CTRL_U2_PORT_HOST_SEL;
writel(value, &ippc->u2_ctrl_p[i]);
}
/*
* wait for clocks to be stable, and clock domains reset to
* be inactive after power on and enable ports
*/
check_val = STS1_SYSPLL_STABLE | STS1_REF_RST |
STS1_SYS125_RST | STS1_XHCI_RST;
if (mtk->num_u3_ports > u3_ports_disabed)
check_val |= STS1_U3_MAC_RST;
ret = readl_poll_timeout(&ippc->ip_pw_sts1, value,
(check_val == (value & check_val)), 100, 20000);
if (ret) {
dev_err(mtk->dev, "clocks are not stable (0x%x)\n", value);
return ret;
}
return 0;
}
static int xhci_mtk_host_disable(struct xhci_hcd_mtk *mtk)
{
struct mu3c_ippc_regs __iomem *ippc = mtk->ippc_regs;
u32 value;
int ret;
int i;
if (!mtk->has_ippc)
return 0;
/* power down u3 ports except skipped ones */
for (i = 0; i < mtk->num_u3_ports; i++) {
if ((0x1 << i) & mtk->u3p_dis_msk)
continue;
value = readl(&ippc->u3_ctrl_p[i]);
value |= CTRL_U3_PORT_PDN;
writel(value, &ippc->u3_ctrl_p[i]);
}
/* power down all u2 ports */
for (i = 0; i < mtk->num_u2_ports; i++) {
value = readl(&ippc->u2_ctrl_p[i]);
value |= CTRL_U2_PORT_PDN;
writel(value, &ippc->u2_ctrl_p[i]);
}
/* power down host ip */
value = readl(&ippc->ip_pw_ctr1);
value |= CTRL1_IP_HOST_PDN;
writel(value, &ippc->ip_pw_ctr1);
/* wait for host ip to sleep */
ret = readl_poll_timeout(&ippc->ip_pw_sts1, value,
(value & STS1_IP_SLEEP_STS), 100, 100000);
if (ret) {
dev_err(mtk->dev, "ip sleep failed!!!\n");
return ret;
}
return 0;
}
static int xhci_mtk_ssusb_config(struct xhci_hcd_mtk *mtk)
{
struct mu3c_ippc_regs __iomem *ippc = mtk->ippc_regs;
u32 value;
if (!mtk->has_ippc)
return 0;
/* reset whole ip */
value = readl(&ippc->ip_pw_ctr0);
value |= CTRL0_IP_SW_RST;
writel(value, &ippc->ip_pw_ctr0);
udelay(1);
value = readl(&ippc->ip_pw_ctr0);
value &= ~CTRL0_IP_SW_RST;
writel(value, &ippc->ip_pw_ctr0);
/*
* device ip is default power-on in fact
* power down device ip, otherwise ip-sleep will fail
*/
value = readl(&ippc->ip_pw_ctr2);
value |= CTRL2_IP_DEV_PDN;
writel(value, &ippc->ip_pw_ctr2);
value = readl(&ippc->ip_xhci_cap);
mtk->num_u3_ports = CAP_U3_PORT_NUM(value);
mtk->num_u2_ports = CAP_U2_PORT_NUM(value);
dev_dbg(mtk->dev, "%s u2p:%d, u3p:%d\n", __func__,
mtk->num_u2_ports, mtk->num_u3_ports);
return xhci_mtk_host_enable(mtk);
}
/* ignore the error if the clock does not exist */
static struct clk *optional_clk_get(struct device *dev, const char *id)
{
struct clk *opt_clk;
opt_clk = devm_clk_get(dev, id);
/* ignore error number except EPROBE_DEFER */
if (IS_ERR(opt_clk) && (PTR_ERR(opt_clk) != -EPROBE_DEFER))
opt_clk = NULL;
return opt_clk;
}
static int xhci_mtk_clks_get(struct xhci_hcd_mtk *mtk)
{
struct device *dev = mtk->dev;
mtk->sys_clk = devm_clk_get(dev, "sys_ck");
if (IS_ERR(mtk->sys_clk)) {
dev_err(dev, "fail to get sys_ck\n");
return PTR_ERR(mtk->sys_clk);
}
mtk->ref_clk = optional_clk_get(dev, "ref_ck");
if (IS_ERR(mtk->ref_clk))
return PTR_ERR(mtk->ref_clk);
mtk->mcu_clk = optional_clk_get(dev, "mcu_ck");
if (IS_ERR(mtk->mcu_clk))
return PTR_ERR(mtk->mcu_clk);
mtk->dma_clk = optional_clk_get(dev, "dma_ck");
return PTR_ERR_OR_ZERO(mtk->dma_clk);
}
static int xhci_mtk_clks_enable(struct xhci_hcd_mtk *mtk)
{
int ret;
ret = clk_prepare_enable(mtk->ref_clk);
if (ret) {
dev_err(mtk->dev, "failed to enable ref_clk\n");
goto ref_clk_err;
}
ret = clk_prepare_enable(mtk->sys_clk);
if (ret) {
dev_err(mtk->dev, "failed to enable sys_clk\n");
goto sys_clk_err;
}
ret = clk_prepare_enable(mtk->mcu_clk);
if (ret) {
dev_err(mtk->dev, "failed to enable mcu_clk\n");
goto mcu_clk_err;
}
ret = clk_prepare_enable(mtk->dma_clk);
if (ret) {
dev_err(mtk->dev, "failed to enable dma_clk\n");
goto dma_clk_err;
}
return 0;
dma_clk_err:
clk_disable_unprepare(mtk->mcu_clk);
mcu_clk_err:
clk_disable_unprepare(mtk->sys_clk);
sys_clk_err:
clk_disable_unprepare(mtk->ref_clk);
ref_clk_err:
return ret;
}
static void xhci_mtk_clks_disable(struct xhci_hcd_mtk *mtk)
{
clk_disable_unprepare(mtk->dma_clk);
clk_disable_unprepare(mtk->mcu_clk);
clk_disable_unprepare(mtk->sys_clk);
clk_disable_unprepare(mtk->ref_clk);
}
/* only clocks can be turn off for ip-sleep wakeup mode */
static void usb_wakeup_ip_sleep_set(struct xhci_hcd_mtk *mtk, bool enable)
{
u32 reg, msk, val;
switch (mtk->uwk_vers) {
case SSUSB_UWK_V1:
reg = mtk->uwk_reg_base + PERI_WK_CTRL1;
msk = WC1_IS_EN | WC1_IS_C(0xf) | WC1_IS_P;
val = enable ? (WC1_IS_EN | WC1_IS_C(0x8)) : 0;
break;
case SSUSB_UWK_V2:
reg = mtk->uwk_reg_base + PERI_SSUSB_SPM_CTRL;
msk = SSC_IP_SLEEP_EN | SSC_SPM_INT_EN;
val = enable ? msk : 0;
break;
default:
return;
}
regmap_update_bits(mtk->uwk, reg, msk, val);
}
static int usb_wakeup_of_property_parse(struct xhci_hcd_mtk *mtk,
struct device_node *dn)
{
struct of_phandle_args args;
int ret;
/* Wakeup function is optional */
mtk->uwk_en = of_property_read_bool(dn, "wakeup-source");
if (!mtk->uwk_en)
return 0;
ret = of_parse_phandle_with_fixed_args(dn,
"mediatek,syscon-wakeup", 2, 0, &args);
if (ret)
return ret;
mtk->uwk_reg_base = args.args[0];
mtk->uwk_vers = args.args[1];
mtk->uwk = syscon_node_to_regmap(args.np);
of_node_put(args.np);
dev_info(mtk->dev, "uwk - reg:0x%x, version:%d\n",
mtk->uwk_reg_base, mtk->uwk_vers);
return PTR_ERR_OR_ZERO(mtk->uwk);
}
static void usb_wakeup_set(struct xhci_hcd_mtk *mtk, bool enable)
{
if (mtk->uwk_en)
usb_wakeup_ip_sleep_set(mtk, enable);
}
static int xhci_mtk_setup(struct usb_hcd *hcd);
static const struct xhci_driver_overrides xhci_mtk_overrides __initconst = {
.reset = xhci_mtk_setup,
};
static struct hc_driver __read_mostly xhci_mtk_hc_driver;
static int xhci_mtk_ldos_enable(struct xhci_hcd_mtk *mtk)
{
int ret;
ret = regulator_enable(mtk->vbus);
if (ret) {
dev_err(mtk->dev, "failed to enable vbus\n");
return ret;
}
ret = regulator_enable(mtk->vusb33);
if (ret) {
dev_err(mtk->dev, "failed to enable vusb33\n");
regulator_disable(mtk->vbus);
return ret;
}
return 0;
}
static void xhci_mtk_ldos_disable(struct xhci_hcd_mtk *mtk)
{
regulator_disable(mtk->vbus);
regulator_disable(mtk->vusb33);
}
static void xhci_mtk_quirks(struct device *dev, struct xhci_hcd *xhci)
{
struct usb_hcd *hcd = xhci_to_hcd(xhci);
struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
/*
* 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;
xhci->quirks |= XHCI_MTK_HOST;
/*
* MTK host controller gives a spurious successful event after a
* short transfer. Ignore it.
*/
xhci->quirks |= XHCI_SPURIOUS_SUCCESS;
if (mtk->lpm_support)
xhci->quirks |= XHCI_LPM_SUPPORT;
}
/* called during probe() after chip reset completes */
static int xhci_mtk_setup(struct usb_hcd *hcd)
{
struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
int ret;
if (usb_hcd_is_primary_hcd(hcd)) {
ret = xhci_mtk_ssusb_config(mtk);
if (ret)
return ret;
}
ret = xhci_gen_setup(hcd, xhci_mtk_quirks);
if (ret)
return ret;
if (usb_hcd_is_primary_hcd(hcd)) {
ret = xhci_mtk_sch_init(mtk);
if (ret)
return ret;
}
return ret;
}
static int xhci_mtk_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
struct xhci_hcd_mtk *mtk;
const struct hc_driver *driver;
struct xhci_hcd *xhci;
struct resource *res;
struct usb_hcd *hcd;
int ret = -ENODEV;
int irq;
if (usb_disabled())
return -ENODEV;
driver = &xhci_mtk_hc_driver;
mtk = devm_kzalloc(dev, sizeof(*mtk), GFP_KERNEL);
if (!mtk)
return -ENOMEM;
mtk->dev = dev;
mtk->vbus = devm_regulator_get(dev, "vbus");
if (IS_ERR(mtk->vbus)) {
dev_err(dev, "fail to get vbus\n");
return PTR_ERR(mtk->vbus);
}
mtk->vusb33 = devm_regulator_get(dev, "vusb33");
if (IS_ERR(mtk->vusb33)) {
dev_err(dev, "fail to get vusb33\n");
return PTR_ERR(mtk->vusb33);
}
ret = xhci_mtk_clks_get(mtk);
if (ret)
return ret;
mtk->lpm_support = of_property_read_bool(node, "usb3-lpm-capable");
/* optional property, ignore the error if it does not exist */
of_property_read_u32(node, "mediatek,u3p-dis-msk",
&mtk->u3p_dis_msk);
ret = usb_wakeup_of_property_parse(mtk, node);
if (ret) {
dev_err(dev, "failed to parse uwk property\n");
return ret;
}
pm_runtime_enable(dev);
pm_runtime_get_sync(dev);
device_enable_async_suspend(dev);
ret = xhci_mtk_ldos_enable(mtk);
if (ret)
goto disable_pm;
ret = xhci_mtk_clks_enable(mtk);
if (ret)
goto disable_ldos;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = irq;
goto disable_clk;
}
/* Initialize dma_mask and coherent_dma_mask to 32-bits */
ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
if (ret)
goto disable_clk;
hcd = usb_create_hcd(driver, dev, dev_name(dev));
if (!hcd) {
ret = -ENOMEM;
goto disable_clk;
}
/*
* USB 2.0 roothub is stored in the platform_device.
* Swap it with mtk HCD.
*/
mtk->hcd = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, mtk);
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mac");
hcd->regs = devm_ioremap_resource(dev, res);
if (IS_ERR(hcd->regs)) {
ret = PTR_ERR(hcd->regs);
goto put_usb2_hcd;
}
hcd->rsrc_start = res->start;
hcd->rsrc_len = resource_size(res);
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ippc");
if (res) { /* ippc register is optional */
mtk->ippc_regs = devm_ioremap_resource(dev, res);
if (IS_ERR(mtk->ippc_regs)) {
ret = PTR_ERR(mtk->ippc_regs);
goto put_usb2_hcd;
}
mtk->has_ippc = true;
} else {
mtk->has_ippc = false;
}
device_init_wakeup(dev, true);
xhci = hcd_to_xhci(hcd);
xhci->main_hcd = hcd;
/*
* imod_interval is the interrupt moderation value in nanoseconds.
* The increment interval is 8 times as much as that defined in
* the xHCI spec on MTK's controller.
*/
xhci->imod_interval = 5000;
device_property_read_u32(dev, "imod-interval-ns", &xhci->imod_interval);
xhci->shared_hcd = usb_create_shared_hcd(driver, dev,
dev_name(dev), hcd);
if (!xhci->shared_hcd) {
ret = -ENOMEM;
goto disable_device_wakeup;
}
ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
if (ret)
goto put_usb3_hcd;
if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
xhci->shared_hcd->can_do_streams = 1;
ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
if (ret)
goto dealloc_usb2_hcd;
return 0;
dealloc_usb2_hcd:
usb_remove_hcd(hcd);
put_usb3_hcd:
xhci_mtk_sch_exit(mtk);
usb_put_hcd(xhci->shared_hcd);
disable_device_wakeup:
device_init_wakeup(dev, false);
put_usb2_hcd:
usb_put_hcd(hcd);
disable_clk:
xhci_mtk_clks_disable(mtk);
disable_ldos:
xhci_mtk_ldos_disable(mtk);
disable_pm:
pm_runtime_put_sync(dev);
pm_runtime_disable(dev);
return ret;
}
static int xhci_mtk_remove(struct platform_device *dev)
{
struct xhci_hcd_mtk *mtk = platform_get_drvdata(dev);
struct usb_hcd *hcd = mtk->hcd;
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
struct usb_hcd *shared_hcd = xhci->shared_hcd;
usb_remove_hcd(shared_hcd);
xhci->shared_hcd = NULL;
device_init_wakeup(&dev->dev, false);
usb_remove_hcd(hcd);
usb_put_hcd(shared_hcd);
usb_put_hcd(hcd);
xhci_mtk_sch_exit(mtk);
xhci_mtk_clks_disable(mtk);
xhci_mtk_ldos_disable(mtk);
pm_runtime_put_sync(&dev->dev);
pm_runtime_disable(&dev->dev);
return 0;
}
/*
* if ip sleep fails, and all clocks are disabled, access register will hang
* AHB bus, so stop polling roothubs to avoid regs access on bus suspend.
* and no need to check whether ip sleep failed or not; this will cause SPM
* to wake up system immediately after system suspend complete if ip sleep
* fails, it is what we wanted.
*/
static int __maybe_unused xhci_mtk_suspend(struct device *dev)
{
struct xhci_hcd_mtk *mtk = dev_get_drvdata(dev);
struct usb_hcd *hcd = mtk->hcd;
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
xhci_dbg(xhci, "%s: stop port polling\n", __func__);
clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
del_timer_sync(&hcd->rh_timer);
clear_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
del_timer_sync(&xhci->shared_hcd->rh_timer);
xhci_mtk_host_disable(mtk);
xhci_mtk_clks_disable(mtk);
usb_wakeup_set(mtk, true);
return 0;
}
static int __maybe_unused xhci_mtk_resume(struct device *dev)
{
struct xhci_hcd_mtk *mtk = dev_get_drvdata(dev);
struct usb_hcd *hcd = mtk->hcd;
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
usb_wakeup_set(mtk, false);
xhci_mtk_clks_enable(mtk);
xhci_mtk_host_enable(mtk);
xhci_dbg(xhci, "%s: restart port polling\n", __func__);
set_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
usb_hcd_poll_rh_status(xhci->shared_hcd);
set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
usb_hcd_poll_rh_status(hcd);
return 0;
}
static const struct dev_pm_ops xhci_mtk_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(xhci_mtk_suspend, xhci_mtk_resume)
};
#define DEV_PM_OPS IS_ENABLED(CONFIG_PM) ? &xhci_mtk_pm_ops : NULL
#ifdef CONFIG_OF
static const struct of_device_id mtk_xhci_of_match[] = {
{ .compatible = "mediatek,mt8173-xhci"},
{ .compatible = "mediatek,mtk-xhci"},
{ },
};
MODULE_DEVICE_TABLE(of, mtk_xhci_of_match);
#endif
static struct platform_driver mtk_xhci_driver = {
.probe = xhci_mtk_probe,
.remove = xhci_mtk_remove,
.driver = {
.name = "xhci-mtk",
.pm = DEV_PM_OPS,
.of_match_table = of_match_ptr(mtk_xhci_of_match),
},
};
MODULE_ALIAS("platform:xhci-mtk");
static int __init xhci_mtk_init(void)
{
xhci_init_driver(&xhci_mtk_hc_driver, &xhci_mtk_overrides);
return platform_driver_register(&mtk_xhci_driver);
}
module_init(xhci_mtk_init);
static void __exit xhci_mtk_exit(void)
{
platform_driver_unregister(&mtk_xhci_driver);
}
module_exit(xhci_mtk_exit);
MODULE_AUTHOR("Chunfeng Yun <chunfeng.yun@mediatek.com>");
MODULE_DESCRIPTION("MediaTek xHCI Host Controller Driver");
MODULE_LICENSE("GPL v2");