svn commit: r271897 - stable/9/sys/dev/usb/serial

[Hans Petter Selasky]

Author: hselasky
Date: Sat Sep 20 08:01:50 2014
New Revision: 271897
URL: http://svnweb.freebsd.org/changeset/base/271897

Log:
  MFC r271492:
  Workaround for receiving Voice Calls using the E1750 dongle from
  Huawei. It might appear as if the firmware is allocating memory blocks
  according to the USB transfer size and if there is initially a lot of
  data, like at the answering machine prompt, it simply dies without any
  apparent reason. The simple workaround for this is to force a zero
  length packet at hardware level after every 512 bytes of data. This
  will force the other side to use smaller memory blocks aswell.

Modified:
  stable/9/sys/dev/usb/serial/u3g.c
Directory Properties:
  stable/9/sys/   (props changed)
  stable/9/sys/dev/   (props changed)

Modified: stable/9/sys/dev/usb/serial/u3g.c
==============================================================================
--- stable/9/sys/dev/usb/serial/u3g.c	Sat Sep 20 07:59:34 2014	(r271896)
+++ stable/9/sys/dev/usb/serial/u3g.c	Sat Sep 20 08:01:50 2014	(r271897)
@@ -75,6 +75,8 @@ SYSCTL_INT(_hw_usb_u3g, OID_AUTO, debug,
 #define	U3G_MAXPORTS		12
 #define	U3G_CONFIG_INDEX	0
 #define	U3G_BSIZE		2048
+#define	U3G_TXSIZE		(U3G_BSIZE / U3G_TXFRAMES)
+#define	U3G_TXFRAMES		4
 
 #define	U3GSP_GPRS		0
 #define	U3GSP_EDGE		1
@@ -153,6 +155,7 @@ static const struct usb_config u3g_confi
 		.endpoint = UE_ADDR_ANY,
 		.direction = UE_DIR_OUT,
 		.bufsize = U3G_BSIZE,/* bytes */
+		.frames = U3G_TXFRAMES,
 		.flags = {.pipe_bof = 1,.force_short_xfer = 1,},
 		.callback = &u3g_write_callback,
 	},
@@ -1013,14 +1016,22 @@ u3g_write_callback(struct usb_xfer *xfer
 	struct ucom_softc *ucom = usbd_xfer_softc(xfer);
 	struct usb_page_cache *pc;
 	uint32_t actlen;
+	uint32_t frame;
 
 	switch (USB_GET_STATE(xfer)) {
 	case USB_ST_TRANSFERRED:
 	case USB_ST_SETUP:
 tr_setup:
-		pc = usbd_xfer_get_frame(xfer, 0);
-		if (ucom_get_data(ucom, pc, 0, U3G_BSIZE, &actlen)) {
-			usbd_xfer_set_frame_len(xfer, 0, actlen);
+		for (frame = 0; frame != U3G_TXFRAMES; frame++) {
+			usbd_xfer_set_frame_offset(xfer, frame * U3G_TXSIZE, frame);
+
+			pc = usbd_xfer_get_frame(xfer, frame);
+			if (ucom_get_data(ucom, pc, 0, U3G_TXSIZE, &actlen) == 0)
+				break;
+			usbd_xfer_set_frame_len(xfer, frame, actlen);
+		}
+		if (frame != 0) {
+			usbd_xfer_set_frames(xfer, frame);
 			usbd_transfer_submit(xfer);
 		}
 		break;