usb: gadget: storage: fix mass storage gadgets to work with Synopsys UDC
The Synopsys USB device controller requires all OUT transfer request
lengths to be aligned to max packet size. The mass storage gadgets do
not meet this requirement for Super Speed. The gadgets already have a
function which performs this alignment for CBW packets, so use it for
data packets too.
The alternative would be to implement bounce buffers in the DWC3
driver, but that could have a significant impact on performance.
This version is based upon a more-correct patch written by Alan
Stern.
Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c
index 12ac30b..a230009 100644
--- a/drivers/usb/gadget/file_storage.c
+++ b/drivers/usb/gadget/file_storage.c
@@ -1335,9 +1335,7 @@
* equal to the buffer size, which is divisible by
* the bulk-out maxpacket size.
*/
- bh->outreq->length = bh->bulk_out_intended_length =
- amount;
- bh->outreq->short_not_ok = 1;
+ set_bulk_out_req_length(fsg, bh, amount);
start_transfer(fsg, fsg->bulk_out, bh->outreq,
&bh->outreq_busy, &bh->state);
fsg->next_buffhd_to_fill = bh->next;
@@ -1370,6 +1368,11 @@
amount = curlun->file_length - file_offset;
}
+ /* Don't accept excess data. The spec doesn't say
+ * what to do in this case. We'll ignore the error.
+ */
+ amount = min(amount, bh->bulk_out_intended_length);
+
/* Don't write a partial block */
amount = round_down(amount, curlun->blksize);
if (amount == 0)
@@ -1409,7 +1412,7 @@
empty_write:
/* Did the host decide to stop early? */
- if (bh->outreq->actual != bh->outreq->length) {
+ if (bh->outreq->actual < bh->bulk_out_intended_length) {
fsg->short_packet_received = 1;
break;
}
@@ -1953,7 +1956,7 @@
fsg->next_buffhd_to_drain = bh->next;
/* A short packet or an error ends everything */
- if (bh->outreq->actual != bh->outreq->length ||
+ if (bh->outreq->actual < bh->bulk_out_intended_length ||
bh->outreq->status != 0) {
raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
return -EINTR;
@@ -1971,9 +1974,7 @@
* equal to the buffer size, which is divisible by
* the bulk-out maxpacket size.
*/
- bh->outreq->length = bh->bulk_out_intended_length =
- amount;
- bh->outreq->short_not_ok = 1;
+ set_bulk_out_req_length(fsg, bh, amount);
start_transfer(fsg, fsg->bulk_out, bh->outreq,
&bh->outreq_busy, &bh->state);
fsg->next_buffhd_to_fill = bh->next;
@@ -2652,7 +2653,6 @@
/* Queue a request to read a Bulk-only CBW */
set_bulk_out_req_length(fsg, bh, USB_BULK_CB_WRAP_LEN);
- bh->outreq->short_not_ok = 1;
start_transfer(fsg, fsg->bulk_out, bh->outreq,
&bh->outreq_busy, &bh->state);