usb: host: ehci-sys: delete useless bus_to_hcd conversion

commit 0521cfd0 upstream.

The ehci platform device's drvdata is the pointer of struct usb_hcd
already, so we doesn't need to call bus_to_hcd conversion again.
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: Unfortunately some EHCI platform sub-drivers 
 point drvdata to a private structure, so only create and remove the
 attributes if drvdata has been set as expected.]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/usb/host/ehci-sysfs.c

@@ -29,7 +29,7 @@ static ssize_t show_companion(struct device *dev,
 	int			count = PAGE_SIZE;
 	char			*ptr = buf;
 
-	ehci = hcd_to_ehci(bus_to_hcd(dev_get_drvdata(dev)));
+	ehci = hcd_to_ehci(dev_get_drvdata(dev));
 	nports = HCS_N_PORTS(ehci->hcs_params);
 
 	for (index = 0; index < nports; ++index) {
@@ -54,7 +54,7 @@ static ssize_t store_companion(struct device *dev,
 	struct ehci_hcd		*ehci;
 	int			portnum, new_owner;
 
-	ehci = hcd_to_ehci(bus_to_hcd(dev_get_drvdata(dev)));
+	ehci = hcd_to_ehci(dev_get_drvdata(dev));
 	new_owner = PORT_OWNER;		/* Owned by companion */
 	if (sscanf(buf, "%d", &portnum) != 1)
 		return -EINVAL;
@@ -85,7 +85,7 @@ static ssize_t show_uframe_periodic_max(struct device *dev,
 	struct ehci_hcd		*ehci;
 	int			n;
 
-	ehci = hcd_to_ehci(bus_to_hcd(dev_get_drvdata(dev)));
+	ehci = hcd_to_ehci(dev_get_drvdata(dev));
 	n = scnprintf(buf, PAGE_SIZE, "%d\n", ehci->uframe_periodic_max);
 	return n;
 }
@@ -102,7 +102,7 @@ static ssize_t store_uframe_periodic_max(struct device *dev,
 	unsigned long		flags;
 	ssize_t			ret;
 
-	ehci = hcd_to_ehci(bus_to_hcd(dev_get_drvdata(dev)));
+	ehci = hcd_to_ehci(dev_get_drvdata(dev));
 	if (kstrtouint(buf, 0, &uframe_periodic_max) < 0)
 		return -EINVAL;
 
@@ -167,6 +167,9 @@ static inline int create_sysfs_files(struct ehci_hcd *ehci)
 	struct device	*controller = ehci_to_hcd(ehci)->self.controller;
 	int	i = 0;
 
+	if (dev_get_drvdata(controller) != ehci_to_hcd(ehci))
+		return 0;
+
 	/* with integrated TT there is no companion! */
 	if (!ehci_is_TDI(ehci))
 		i = device_create_file(controller, &dev_attr_companion);
@@ -182,6 +185,9 @@ static inline void remove_sysfs_files(struct ehci_hcd *ehci)
 {
 	struct device	*controller = ehci_to_hcd(ehci)->self.controller;
 
+	if (dev_get_drvdata(controller) != ehci_to_hcd(ehci))
+		return;
+
 	/* with integrated TT there is no companion! */
 	if (!ehci_is_TDI(ehci))
 		device_remove_file(controller, &dev_attr_companion);