linux/drivers/usb/host/ehci-mxc.c
Daniel Mack f375fc520d usb: ehci-mxc: check for pdata before dereferencing
Commit 7e8d5cd93f ("USB: Add EHCI support for MX27 and MX31 based
boards") introduced code that could potentially lead to a NULL pointer
dereference on driver removal.

Fix this by checking for the value of pdata before dereferencing it.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org> # 2.6.33+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-23 10:46:03 -07:00

232 lines
5.6 KiB
C

/*
* Copyright (c) 2008 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
* Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/usb/otg.h>
#include <linux/usb/ulpi.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/platform_data/usb-ehci-mxc.h>
#include "ehci.h"
#define DRIVER_DESC "Freescale On-Chip EHCI Host driver"
static const char hcd_name[] = "ehci-mxc";
#define ULPI_VIEWPORT_OFFSET 0x170
struct ehci_mxc_priv {
struct clk *usbclk, *ahbclk, *phyclk;
};
static struct hc_driver __read_mostly ehci_mxc_hc_driver;
static const struct ehci_driver_overrides ehci_mxc_overrides __initconst = {
.extra_priv_size = sizeof(struct ehci_mxc_priv),
};
static int ehci_mxc_drv_probe(struct platform_device *pdev)
{
struct mxc_usbh_platform_data *pdata = dev_get_platdata(&pdev->dev);
struct usb_hcd *hcd;
struct resource *res;
int irq, ret;
struct ehci_mxc_priv *priv;
struct device *dev = &pdev->dev;
struct ehci_hcd *ehci;
if (!pdata) {
dev_err(dev, "No platform data given, bailing out.\n");
return -EINVAL;
}
irq = platform_get_irq(pdev, 0);
hcd = usb_create_hcd(&ehci_mxc_hc_driver, dev, dev_name(dev));
if (!hcd)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(dev, "Found HC with no register addr. Check setup!\n");
ret = -ENODEV;
goto err_alloc;
}
hcd->rsrc_start = res->start;
hcd->rsrc_len = resource_size(res);
hcd->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(hcd->regs)) {
ret = PTR_ERR(hcd->regs);
goto err_alloc;
}
hcd->has_tt = 1;
ehci = hcd_to_ehci(hcd);
priv = (struct ehci_mxc_priv *) ehci->priv;
/* enable clocks */
priv->usbclk = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(priv->usbclk)) {
ret = PTR_ERR(priv->usbclk);
goto err_alloc;
}
clk_prepare_enable(priv->usbclk);
priv->ahbclk = devm_clk_get(&pdev->dev, "ahb");
if (IS_ERR(priv->ahbclk)) {
ret = PTR_ERR(priv->ahbclk);
goto err_clk_ahb;
}
clk_prepare_enable(priv->ahbclk);
/* "dr" device has its own clock on i.MX51 */
priv->phyclk = devm_clk_get(&pdev->dev, "phy");
if (IS_ERR(priv->phyclk))
priv->phyclk = NULL;
if (priv->phyclk)
clk_prepare_enable(priv->phyclk);
/* call platform specific init function */
if (pdata->init) {
ret = pdata->init(pdev);
if (ret) {
dev_err(dev, "platform init failed\n");
goto err_init;
}
/* platforms need some time to settle changed IO settings */
mdelay(10);
}
/* EHCI registers start at offset 0x100 */
ehci->caps = hcd->regs + 0x100;
ehci->regs = hcd->regs + 0x100 +
HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
/* set up the PORTSCx register */
ehci_writel(ehci, pdata->portsc, &ehci->regs->port_status[0]);
/* is this really needed? */
msleep(10);
/* Initialize the transceiver */
if (pdata->otg) {
pdata->otg->io_priv = hcd->regs + ULPI_VIEWPORT_OFFSET;
ret = usb_phy_init(pdata->otg);
if (ret) {
dev_err(dev, "unable to init transceiver, probably missing\n");
ret = -ENODEV;
goto err_add;
}
ret = otg_set_vbus(pdata->otg->otg, 1);
if (ret) {
dev_err(dev, "unable to enable vbus on transceiver\n");
goto err_add;
}
}
platform_set_drvdata(pdev, hcd);
ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
if (ret)
goto err_add;
return 0;
err_add:
if (pdata && pdata->exit)
pdata->exit(pdev);
err_init:
if (priv->phyclk)
clk_disable_unprepare(priv->phyclk);
clk_disable_unprepare(priv->ahbclk);
err_clk_ahb:
clk_disable_unprepare(priv->usbclk);
err_alloc:
usb_put_hcd(hcd);
return ret;
}
static int ehci_mxc_drv_remove(struct platform_device *pdev)
{
struct mxc_usbh_platform_data *pdata = dev_get_platdata(&pdev->dev);
struct usb_hcd *hcd = platform_get_drvdata(pdev);
struct ehci_hcd *ehci = hcd_to_ehci(hcd);
struct ehci_mxc_priv *priv = (struct ehci_mxc_priv *) ehci->priv;
usb_remove_hcd(hcd);
if (pdata && pdata->exit)
pdata->exit(pdev);
if (pdata && pdata->otg)
usb_phy_shutdown(pdata->otg);
clk_disable_unprepare(priv->usbclk);
clk_disable_unprepare(priv->ahbclk);
if (priv->phyclk)
clk_disable_unprepare(priv->phyclk);
usb_put_hcd(hcd);
return 0;
}
MODULE_ALIAS("platform:mxc-ehci");
static struct platform_driver ehci_mxc_driver = {
.probe = ehci_mxc_drv_probe,
.remove = ehci_mxc_drv_remove,
.shutdown = usb_hcd_platform_shutdown,
.driver = {
.name = "mxc-ehci",
},
};
static int __init ehci_mxc_init(void)
{
if (usb_disabled())
return -ENODEV;
pr_info("%s: " DRIVER_DESC "\n", hcd_name);
ehci_init_driver(&ehci_mxc_hc_driver, &ehci_mxc_overrides);
return platform_driver_register(&ehci_mxc_driver);
}
module_init(ehci_mxc_init);
static void __exit ehci_mxc_cleanup(void)
{
platform_driver_unregister(&ehci_mxc_driver);
}
module_exit(ehci_mxc_cleanup);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Sascha Hauer");
MODULE_LICENSE("GPL");