usb: storage: Only clear READY flag on error

Clear the USB_READY flag in the storage driver only in case there
is an error, otherwise usb_stor_BBB_transport() waits 5 mS before
doing anything every single time.

This is because the USB_READY flag is only ever set in
usb_test_unit_ready(), which is called only upon storage device
probe, not between each and every request. However, the device
cannot move out of USB_READY state once it was initialized.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Simon Glass <sjg@chromium.org>
diff --git a/common/usb_storage.c b/common/usb_storage.c
index 337c4e1..097b672 100644
--- a/common/usb_storage.c
+++ b/common/usb_storage.c
@@ -1180,6 +1180,7 @@
 		srb->pdata = (unsigned char *)buf_addr;
 		if (usb_read_10(srb, ss, start, smallblks)) {
 			debug("Read ERROR\n");
+			ss->flags &= ~USB_READY;
 			usb_request_sense(srb, ss);
 			if (retry--)
 				goto retry_it;
@@ -1190,7 +1191,6 @@
 		blks -= smallblks;
 		buf_addr += srb->datalen;
 	} while (blks != 0);
-	ss->flags &= ~USB_READY;
 
 	debug("usb_read: end startblk " LBAF ", blccnt %x buffer %lx\n",
 	      start, smallblks, buf_addr);
@@ -1265,6 +1265,7 @@
 		srb->pdata = (unsigned char *)buf_addr;
 		if (usb_write_10(srb, ss, start, smallblks)) {
 			debug("Write ERROR\n");
+			ss->flags &= ~USB_READY;
 			usb_request_sense(srb, ss);
 			if (retry--)
 				goto retry_it;
@@ -1275,7 +1276,6 @@
 		blks -= smallblks;
 		buf_addr += srb->datalen;
 	} while (blks != 0);
-	ss->flags &= ~USB_READY;
 
 	debug("usb_write: end startblk " LBAF ", blccnt %x buffer %lx\n",
 	      start, smallblks, buf_addr);
@@ -1470,10 +1470,10 @@
 	memset(pccb->pdata, 0, 8);
 	if (usb_read_capacity(pccb, ss) != 0) {
 		printf("READ_CAP ERROR\n");
+		ss->flags &= ~USB_READY;
 		cap[0] = 2880;
 		cap[1] = 0x200;
 	}
-	ss->flags &= ~USB_READY;
 	debug("Read Capacity returns: 0x%08x, 0x%08x\n", cap[0], cap[1]);
 #if 0
 	if (cap[0] > (0x200000 * 10)) /* greater than 10 GByte */