usb: isp1760: fix qtd fill length

[ Upstream commit cbfa3ef ]

When trying to send bulks bigger than the biggest block size
we need to split them over several qtd. Fix this limiting the
maximum qtd size to largest block size.

Reported-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
Link: https://lore.kernel.org/r/20210827131154.4151862-3-rui.silva@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/usb/isp1760/isp1760-hcd.c

@@ -1826,9 +1826,11 @@ static void packetize_urb(struct usb_hcd *hcd,
 			goto cleanup;
 
 		if (len > mem->blocks_size[ISP176x_BLOCK_NUM - 1])
-			len = mem->blocks_size[ISP176x_BLOCK_NUM - 1];
+			this_qtd_len = mem->blocks_size[ISP176x_BLOCK_NUM - 1];
+		else
+			this_qtd_len = len;
 
-		this_qtd_len = qtd_fill(qtd, buf, len);
+		this_qtd_len = qtd_fill(qtd, buf, this_qtd_len);
 		list_add_tail(&qtd->qtd_list, head);
 
 		len -= this_qtd_len;