USB storage count

Here's another USB storage patch. Currently U-Boot handles storage
devices #0 - #4 as valid devices, even if there is none connected. This
patch fixes usb_stor_get_dev() to check detected device count instead
of MAX-define.

This is very important for ill behaving devices. usb_dev_desc[] can be
partially initialized if device probe fails.

After fixing get_dev() it was easy to fix "usb part" etc commands.
Previously it outputed "Unknown partition table" five times, now it's
"no USB devices available".

Signed-off-by: Kim B. Heino <Kim.Heino@bluegiga.com>

common/cmd_usb.c

@@ -387,7 +387,7 @@ int do_usbboot(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 
 	dev = simple_strtoul(boot_device, &ep, 16);
 	stor_dev = usb_stor_get_dev(dev);
-	if (stor_dev->type == DEV_TYPE_UNKNOWN) {
+	if (stor_dev == NULL || stor_dev->type == DEV_TYPE_UNKNOWN) {
 		printf("\n** Device %d not available\n", dev);
 		return 1;
 	}
@@ -595,8 +595,10 @@ int do_usb(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 	if (strncmp(argv[1], "part", 4) == 0) {
 		int devno, ok = 0;
 		if (argc == 2) {
-			for (devno = 0; devno < USB_MAX_STOR_DEV; ++devno) {
+			for (devno = 0; ; ++devno) {
 				stor_dev = usb_stor_get_dev(devno);
+				if (stor_dev == NULL)
+					break;
 				if (stor_dev->type != DEV_TYPE_UNKNOWN) {
 					ok++;
 					if (devno)
@@ -608,7 +610,8 @@ int do_usb(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 		} else {
 			devno = simple_strtoul(argv[2], NULL, 16);
 			stor_dev = usb_stor_get_dev(devno);
-			if (stor_dev->type != DEV_TYPE_UNKNOWN) {
+			if (stor_dev != NULL &&
+			    stor_dev->type != DEV_TYPE_UNKNOWN) {
 				ok++;
 				debug("print_part of %x\n", devno);
 				print_part(stor_dev);
@@ -668,12 +671,12 @@ int do_usb(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 		if (argc == 3) {
 			int dev = (int)simple_strtoul(argv[2], NULL, 10);
 			printf("\nUSB device %d: ", dev);
-			if (dev >= USB_MAX_STOR_DEV) {
+			stor_dev = usb_stor_get_dev(dev);
+			if (stor_dev == NULL) {
 				printf("unknown device\n");
 				return 1;
 			}
 			printf("\n    Device %d: ", dev);
-			stor_dev = usb_stor_get_dev(dev);
 			dev_print(stor_dev);
 			if (stor_dev->type == DEV_TYPE_UNKNOWN)
 				return 1;

common/usb_storage.c

@@ -175,7 +175,7 @@ void uhci_show_temp_int_td(void);
 
 block_dev_desc_t *usb_stor_get_dev(int index)
 {
-	return (index < USB_MAX_STOR_DEV) ? &usb_dev_desc[index] : NULL;
+	return (index < usb_max_devs) ? &usb_dev_desc[index] : NULL;
 }