Fix for USB sticks not working on ARM while using GCC 4.x compilers

[platform/kernel/u-boot.git] / common / usb.c

diff --git a/common/usb.c b/common/usb.c
index a45d113..4d64ccb 100644 (file)
--- a/common/usb.c
+++ b/common/usb.c
@@ -50,8 +50,6 @@
 #include <linux/ctype.h>
 #include <asm/byteorder.h>
 
-#if defined(CONFIG_CMD_USB)
-
 #include <usb.h>
 #ifdef CONFIG_4xx
 #include <asm/4xx_pci.h>
@@ -128,10 +126,15 @@ int usb_init(void)
  */
 int usb_stop(void)
 {
-       asynch_allowed=1;
-       usb_started = 0;
-       usb_hub_reset();
-       return usb_lowlevel_stop();
+       int res = 0;
+
+       if (usb_started) {
+               asynch_allowed = 1;
+               usb_started = 0;
+               usb_hub_reset();
+               res = usb_lowlevel_stop();
+       }
+       return res;
 }
 
 /*
@@ -242,40 +245,59 @@ int usb_maxpacket(struct usb_device *dev,unsigned long pipe)
                return(dev->epmaxpacketin[((pipe>>15) & 0xf)]);
 }
 
+/* The routine usb_set_maxpacket_ep() is extracted from the loop of routine
+ * usb_set_maxpacket(), because the optimizer of GCC 4.x chokes on this routine
+ * when it is inlined in 1 single routine. What happens is that the register r3
+ * is used as loop-count 'i', but gets overwritten later on.
+ * This is clearly a compiler bug, but it is easier to workaround it here than
+ * to update the compiler (Occurs with at least several GCC 4.{1,2},x
+ * CodeSourcery compilers like e.g. 2007q3, 2008q1, 2008q3 lite editions on ARM)
+ */
+static void  __attribute__((noinline))
+usb_set_maxpacket_ep(struct usb_device *dev, struct usb_endpoint_descriptor *ep)
+{
+       int b;
+
+       b = ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
+
+       if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
+                                               USB_ENDPOINT_XFER_CONTROL) {
+               /* Control => bidirectional */
+               dev->epmaxpacketout[b] = ep->wMaxPacketSize;
+               dev->epmaxpacketin [b] = ep->wMaxPacketSize;
+               USB_PRINTF("##Control EP epmaxpacketout/in[%d] = %d\n",
+                          b, dev->epmaxpacketin[b]);
+       } else {
+               if ((ep->bEndpointAddress & 0x80) == 0) {
+                       /* OUT Endpoint */
+                       if (ep->wMaxPacketSize > dev->epmaxpacketout[b]) {
+                               dev->epmaxpacketout[b] = ep->wMaxPacketSize;
+                               USB_PRINTF("##EP epmaxpacketout[%d] = %d\n",
+                                          b, dev->epmaxpacketout[b]);
+                       }
+               } else {
+                       /* IN Endpoint */
+                       if (ep->wMaxPacketSize > dev->epmaxpacketin[b]) {
+                               dev->epmaxpacketin[b] = ep->wMaxPacketSize;
+                               USB_PRINTF("##EP epmaxpacketin[%d] = %d\n",
+                                          b, dev->epmaxpacketin[b]);
+                       }
+               } /* if out */
+       } /* if control */
+}
+
 /*
  * set the max packed value of all endpoints in the given configuration
  */
 int usb_set_maxpacket(struct usb_device *dev)
 {
-       int i,ii,b;
-       struct usb_endpoint_descriptor *ep;
+       int i, ii;
 
-       for(i=0; i<dev->config.bNumInterfaces;i++) {
-               for(ii=0; ii<dev->config.if_desc[i].bNumEndpoints; ii++) {
-                       ep = &dev->config.if_desc[i].ep_desc[ii];
-                       b=ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
+       for (i = 0; i < dev->config.bNumInterfaces; i++)
+               for (ii = 0; ii < dev->config.if_desc[i].bNumEndpoints; ii++)
+                       usb_set_maxpacket_ep(dev,
+                                         &dev->config.if_desc[i].ep_desc[ii]);
 
-                       if((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)==USB_ENDPOINT_XFER_CONTROL) {        /* Control => bidirectional */
-                               dev->epmaxpacketout[b] = ep->wMaxPacketSize;
-                               dev->epmaxpacketin [b] = ep->wMaxPacketSize;
-                               USB_PRINTF("##Control EP epmaxpacketout/in[%d] = %d\n",b,dev->epmaxpacketin[b]);
-                       }
-                       else {
-                               if ((ep->bEndpointAddress & 0x80)==0) { /* OUT Endpoint */
-                                       if(ep->wMaxPacketSize > dev->epmaxpacketout[b]) {
-                                               dev->epmaxpacketout[b] = ep->wMaxPacketSize;
-                                               USB_PRINTF("##EP epmaxpacketout[%d] = %d\n",b,dev->epmaxpacketout[b]);
-                                       }
-                               }
-                               else  { /* IN Endpoint */
-                                       if(ep->wMaxPacketSize > dev->epmaxpacketin[b]) {
-                                               dev->epmaxpacketin[b] = ep->wMaxPacketSize;
-                                               USB_PRINTF("##EP epmaxpacketin[%d] = %d\n",b,dev->epmaxpacketin[b]);
-                                       }
-                               } /* if out */
-                       } /* if control */
-               } /* for each endpoint */
-       }
        return 0;
 }
 
@@ -1247,6 +1269,4 @@ int usb_hub_probe(struct usb_device *dev, int ifnum)
        return ret;
 }
 
-#endif
-
 /* EOF */