usb_storage: Remove EHCI constraints

Now that the EHCI driver allocates its qTDs from the heap, the MSC driver is
only limited by the SCSI commands it uses.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Ilya Yanok <ilya.yanok@cogentembedded.com>
Cc: Stefan Herbrechtsmeier <stefan@herbrechtsmeier.net>

diff --git a/common/usb_storage.c b/common/usb_storage.c
index 0cd6399a3c42a228a71c28290a649efc0864cdd4..099edd3fa6c74f47992158360f9366e81f45b0ce 100644 (file)
--- a/common/usb_storage.c
+++ b/common/usb_storage.c
@@ -157,12 +157,13 @@ struct us_data {
 
 #ifdef CONFIG_USB_EHCI
 /*
- * The U-Boot EHCI driver cannot handle more than 5 page aligned buffers
- * of 4096 bytes in a transfer without running itself out of qt_buffers
+ * The U-Boot EHCI driver can handle any transfer length as long as there is
+ * enough free heap space left, but the SCSI READ(10) and WRITE(10) commands are
+ * limited to 65535 blocks.
  */
-#define USB_MAX_XFER_BLK(start, blksz) (((4096 * 5) - (start % 4096)) / blksz)
+#define USB_MAX_XFER_BLK       65535
 #else
-#define USB_MAX_XFER_BLK(start, blksz) 20
+#define USB_MAX_XFER_BLK       20
 #endif
 
 static struct us_data usb_stor[USB_MAX_STOR_DEV];
@@ -1050,7 +1051,7 @@ static void usb_bin_fixup(struct usb_device_descriptor descriptor,
 unsigned long usb_stor_read(int device, unsigned long blknr,
                            unsigned long blkcnt, void *buffer)
 {
-       unsigned long start, blks, buf_addr, max_xfer_blk;
+       unsigned long start, blks, buf_addr;
        unsigned short smallblks;
        struct usb_device *dev;
        struct us_data *ss;
@@ -1092,14 +1093,12 @@ unsigned long usb_stor_read(int device, unsigned long blknr,
                /* XXX need some comment here */
                retry = 2;
                srb->pdata = (unsigned char *)buf_addr;
-               max_xfer_blk = USB_MAX_XFER_BLK(buf_addr,
-                                               usb_dev_desc[device].blksz);
-               if (blks > max_xfer_blk)
-                       smallblks = (unsigned short) max_xfer_blk;
+               if (blks > USB_MAX_XFER_BLK)
+                       smallblks = USB_MAX_XFER_BLK;
                else
                        smallblks = (unsigned short) blks;
 retry_it:
-               if (smallblks == max_xfer_blk)
+               if (smallblks == USB_MAX_XFER_BLK)
                        usb_show_progress();
                srb->datalen = usb_dev_desc[device].blksz * smallblks;
                srb->pdata = (unsigned char *)buf_addr;
@@ -1120,7 +1119,7 @@ retry_it:
                        start, smallblks, buf_addr);
 
        usb_disable_asynch(0); /* asynch transfer allowed */
-       if (blkcnt >= max_xfer_blk)
+       if (blkcnt >= USB_MAX_XFER_BLK)
                debug("\n");
        return blkcnt;
 }
@@ -1128,7 +1127,7 @@ retry_it:
 unsigned long usb_stor_write(int device, unsigned long blknr,
                                unsigned long blkcnt, const void *buffer)
 {
-       unsigned long start, blks, buf_addr, max_xfer_blk;
+       unsigned long start, blks, buf_addr;
        unsigned short smallblks;
        struct usb_device *dev;
        struct us_data *ss;
@@ -1173,14 +1172,12 @@ unsigned long usb_stor_write(int device, unsigned long blknr,
                 */
                retry = 2;
                srb->pdata = (unsigned char *)buf_addr;
-               max_xfer_blk = USB_MAX_XFER_BLK(buf_addr,
-                                               usb_dev_desc[device].blksz);
-               if (blks > max_xfer_blk)
-                       smallblks = (unsigned short) max_xfer_blk;
+               if (blks > USB_MAX_XFER_BLK)
+                       smallblks = USB_MAX_XFER_BLK;
                else
                        smallblks = (unsigned short) blks;
 retry_it:
-               if (smallblks == max_xfer_blk)
+               if (smallblks == USB_MAX_XFER_BLK)
                        usb_show_progress();
                srb->datalen = usb_dev_desc[device].blksz * smallblks;
                srb->pdata = (unsigned char *)buf_addr;
@@ -1201,7 +1198,7 @@ retry_it:
                        start, smallblks, buf_addr);
 
        usb_disable_asynch(0); /* asynch transfer allowed */
-       if (blkcnt >= max_xfer_blk)
+       if (blkcnt >= USB_MAX_XFER_BLK)
                debug("\n");
        return blkcnt;