usb: do explicit unaligned accesses

usb_hub_descriptor has to be packed as it's used for
communication with the device. Member wHubCharacteristics
violates the natural alignment rules.

Use explicit unaligned access functions for this member.
Fixes ARMv7 traping while using USB.

v2: fix typo found by Thomas Langer

v3: rebased on top of u-boot-usb/master

Signed-off-by: Lucas Stach <dev@lynxeye.de>

common/usb_hub.c

@@ -43,6 +43,7 @@
 #include <common.h>
 #include <command.h>
 #include <asm/processor.h>
+#include <asm/unaligned.h>
 #include <linux/ctype.h>
 #include <asm/byteorder.h>
 #include <asm/unaligned.h>
@@ -269,6 +270,7 @@ static int usb_hub_configure(struct usb_device *dev)
 	int i;
 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, USB_BUFSIZ);
 	unsigned char *bitmap;
+	short hubCharacteristics;
 	struct usb_hub_descriptor *descriptor;
 	struct usb_hub_device *hub;
 #ifdef USB_HUB_DEBUG
@@ -304,8 +306,9 @@ static int usb_hub_configure(struct usb_device *dev)
 	}
 	memcpy((unsigned char *)&hub->desc, buffer, descriptor->bLength);
 	/* adjust 16bit values */
-	hub->desc.wHubCharacteristics =
-				le16_to_cpu(descriptor->wHubCharacteristics);
+	put_unaligned(le16_to_cpu(get_unaligned(
+			&descriptor->wHubCharacteristics)),
+			&hub->desc.wHubCharacteristics);
 	/* set the bitmap */
 	bitmap = (unsigned char *)&hub->desc.DeviceRemovable[0];
 	/* devices not removable by default */
@@ -322,7 +325,8 @@ static int usb_hub_configure(struct usb_device *dev)
 	dev->maxchild = descriptor->bNbrPorts;
 	USB_HUB_PRINTF("%d ports detected\n", dev->maxchild);
 
-	switch (hub->desc.wHubCharacteristics & HUB_CHAR_LPSM) {
+	hubCharacteristics = get_unaligned(&hub->desc.wHubCharacteristics);
+	switch (hubCharacteristics & HUB_CHAR_LPSM) {
 	case 0x00:
 		USB_HUB_PRINTF("ganged power switching\n");
 		break;
@@ -335,12 +339,12 @@ static int usb_hub_configure(struct usb_device *dev)
 		break;
 	}
 
-	if (hub->desc.wHubCharacteristics & HUB_CHAR_COMPOUND)
+	if (hubCharacteristics & HUB_CHAR_COMPOUND)
 		USB_HUB_PRINTF("part of a compound device\n");
 	else
 		USB_HUB_PRINTF("standalone hub\n");
 
-	switch (hub->desc.wHubCharacteristics & HUB_CHAR_OCPM) {
+	switch (hubCharacteristics & HUB_CHAR_OCPM) {
 	case 0x00:
 		USB_HUB_PRINTF("global over-current protection\n");
 		break;

drivers/usb/host/ehci-hcd.c

@@ -22,6 +22,7 @@
  */
 #include <common.h>
 #include <asm/byteorder.h>
+#include <asm/unaligned.h>
 #include <usb.h>
 #include <asm/io.h>
 #include <malloc.h>
@@ -866,10 +867,12 @@ int usb_lowlevel_init(void)
 	printf("Register %x NbrPorts %d\n", reg, descriptor.hub.bNbrPorts);
 	/* Port Indicators */
 	if (HCS_INDICATOR(reg))
-		descriptor.hub.wHubCharacteristics |= 0x80;
+		put_unaligned(get_unaligned(&descriptor.hub.wHubCharacteristics)
+				| 0x80, &descriptor.hub.wHubCharacteristics);
 	/* Port Power Control */
 	if (HCS_PPC(reg))
-		descriptor.hub.wHubCharacteristics |= 0x01;
+		put_unaligned(get_unaligned(&descriptor.hub.wHubCharacteristics)
+				| 0x01, &descriptor.hub.wHubCharacteristics);
 
 	/* Start the host controller. */
 	cmd = ehci_readl(&hcor->or_usbcmd);