Merge tag 'usb-serial-5.5-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next

Johan writes:

USB-serial updates for 5.5-rc1

Here are the USB-serial updates for 5.5-rc1, including:

 - support for a new class of pl2303 devices
 - improved divisor calculations for ch341
 - fixes for a remote-wakeup bug in the moschip drivers
 - improved device-type handling in mos7840
 - various cleanups of mos7840

Included are also some new device ids.

All have been in linux-next with no reported issues.

Signed-off-by: Johan Hovold <johan@kernel.org>

* tag 'usb-serial-5.5-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
  USB: serial: ftdi_sio: add device IDs for U-Blox C099-F9P
  USB: serial: option: add support for Foxconn T77W968 LTE modules
  USB: serial: mos7840: drop port open flag
  USB: serial: mos7840: drop read-urb check
  USB: serial: mos7840: drop port driver data accessors
  USB: serial: mos7840: drop serial struct accessor
  USB: serial: mos7840: drop paranoid serial checks
  USB: serial: mos7840: drop paranoid port checks
  USB: serial: mos7840: drop redundant urb context check
  USB: serial: mos7840: rip out broken interrupt handling
  USB: serial: mos7840: fix probe error handling
  USB: serial: mos7840: document MCS7810 detection hack
  USB: serial: mos7840: clean up device-type handling
  USB: serial: mos7840: fix remote wakeup
  USB: serial: mos7720: fix remote wakeup
  USB: serial: option: add support for DW5821e with eSIM support
  USB: serial: mos7840: add USB ID to support Moxa UPort 2210
  USB: serial: ch341: reimplement line-speed handling
  USB: serial: pl2303: add support for PL2303HXN

8 files changed, 300 insertions, 710 deletions

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index 3bb1fff02bed..df582fe855f0 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -48,12 +48,6 @@
 #define CH341_BIT_DCD 0x08
 #define CH341_BITS_MODEM_STAT 0x0f /* all bits */
 
-/*******************************/
-/* baudrate calculation factor */
-/*******************************/
-#define CH341_BAUDBASE_FACTOR 1532620800
-#define CH341_BAUDBASE_DIVMAX 3
-
 /* Break support - the information used to implement this was gleaned from
  * the Net/FreeBSD uchcom.c driver by Takanori Watanabe.  Domo arigato.
  */
@@ -144,37 +138,96 @@ static int ch341_control_in(struct usb_device *dev,
 	return 0;
 }
 
+#define CH341_CLKRATE		48000000
+#define CH341_CLK_DIV(ps, fact)	(1 << (12 - 3 * (ps) - (fact)))
+#define CH341_MIN_RATE(ps)	(CH341_CLKRATE / (CH341_CLK_DIV((ps), 1) * 512))
+
+static const speed_t ch341_min_rates[] = {
+	CH341_MIN_RATE(0),
+	CH341_MIN_RATE(1),
+	CH341_MIN_RATE(2),
+	CH341_MIN_RATE(3),
+};
+
+/*
+ * The device line speed is given by the following equation:
+ *
+ *	baudrate = 48000000 / (2^(12 - 3 * ps - fact) * div), where
+ *
+ *		0 <= ps <= 3,
+ *		0 <= fact <= 1,
+ *		2 <= div <= 256 if fact = 0, or
+ *		9 <= div <= 256 if fact = 1
+ */
+static int ch341_get_divisor(speed_t speed)
+{
+	unsigned int fact, div, clk_div;
+	int ps;
+
+	/*
+	 * Clamp to supported range, this makes the (ps < 0) and (div < 2)
+	 * sanity checks below redundant.
+	 */
+	speed = clamp(speed, 46U, 3000000U);
+
+	/*
+	 * Start with highest possible base clock (fact = 1) that will give a
+	 * divisor strictly less than 512.
+	 */
+	fact = 1;
+	for (ps = 3; ps >= 0; ps--) {
+		if (speed > ch341_min_rates[ps])
+			break;
+	}
+
+	if (ps < 0)
+		return -EINVAL;
+
+	/* Determine corresponding divisor, rounding down. */
+	clk_div = CH341_CLK_DIV(ps, fact);
+	div = CH341_CLKRATE / (clk_div * speed);
+
+	/* Halve base clock (fact = 0) if required. */
+	if (div < 9 || div > 255) {
+		div /= 2;
+		clk_div *= 2;
+		fact = 0;
+	}
+
+	if (div < 2)
+		return -EINVAL;
+
+	/*
+	 * Pick next divisor if resulting rate is closer to the requested one,
+	 * scale up to avoid rounding errors on low rates.
+	 */
+	if (16 * CH341_CLKRATE / (clk_div * div) - 16 * speed >=
+			16 * speed - 16 * CH341_CLKRATE / (clk_div * (div + 1)))
+		div++;
+
+	return (0x100 - div) << 8 | fact << 2 | ps;
+}
+
 static int ch341_set_baudrate_lcr(struct usb_device *dev,
 				  struct ch341_private *priv, u8 lcr)
 {
-	short a;
+	int val;
 	int r;
-	unsigned long factor;
-	short divisor;
 
 	if (!priv->baud_rate)
 		return -EINVAL;
-	factor = (CH341_BAUDBASE_FACTOR / priv->baud_rate);
-	divisor = CH341_BAUDBASE_DIVMAX;
-
-	while ((factor > 0xfff0) && divisor) {
-		factor >>= 3;
-		divisor--;
-	}
 
-	if (factor > 0xfff0)
+	val = ch341_get_divisor(priv->baud_rate);
+	if (val < 0)
 		return -EINVAL;
 
-	factor = 0x10000 - factor;
-	a = (factor & 0xff00) | divisor;
-
 	/*
 	 * CH341A buffers data until a full endpoint-size packet (32 bytes)
 	 * has been received unless bit 7 is set.
 	 */
-	a |= BIT(7);
+	val |= BIT(7);
 
-	r = ch341_control_out(dev, CH341_REQ_WRITE_REG, 0x1312, a);
+	r = ch341_control_out(dev, CH341_REQ_WRITE_REG, 0x1312, val);
 	if (r)
 		return r;
 
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 25e81faf4c24..9ad44a96dfe3 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1033,6 +1033,9 @@ static const struct usb_device_id id_table_combined[] = {
 	/* Sienna devices */
 	{ USB_DEVICE(FTDI_VID, FTDI_SIENNA_PID) },
 	{ USB_DEVICE(ECHELON_VID, ECHELON_U20_PID) },
+	/* U-Blox devices */
+	{ USB_DEVICE(UBLOX_VID, UBLOX_C099F9P_ZED_PID) },
+	{ USB_DEVICE(UBLOX_VID, UBLOX_C099F9P_ODIN_PID) },
 	{ }					/* Terminating entry */
 };
 
diff --git a/drivers/usb/serial/ftdi_sio_ids.h b/drivers/usb/serial/ftdi_sio_ids.h
index 22d66217cb41..e8373528264c 100644
--- a/drivers/usb/serial/ftdi_sio_ids.h
+++ b/drivers/usb/serial/ftdi_sio_ids.h
@@ -1558,3 +1558,10 @@
  */
 #define UNJO_VID			0x22B7
 #define UNJO_ISODEBUG_V1_PID		0x150D
+
+/*
+ * U-Blox products (http://www.u-blox.com).
+ */
+#define UBLOX_VID			0x1546
+#define UBLOX_C099F9P_ZED_PID		0x0502
+#define UBLOX_C099F9P_ODIN_PID		0x0503
diff --git a/drivers/usb/serial/mos7720.c b/drivers/usb/serial/mos7720.c
index 18110225d506..2ec4eeacebc7 100644
--- a/drivers/usb/serial/mos7720.c
+++ b/drivers/usb/serial/mos7720.c
@@ -1833,10 +1833,6 @@ static int mos7720_startup(struct usb_serial *serial)
 	product = le16_to_cpu(serial->dev->descriptor.idProduct);
 	dev = serial->dev;
 
-	/* setting configuration feature to one */
-	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-			(__u8)0x03, 0x00, 0x01, 0x00, NULL, 0x00, 5000);
-
 	if (product == MOSCHIP_DEVICE_ID_7715) {
 		struct urb *urb = serial->port[0]->interrupt_in_urb;
 
diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index a698d46ba773..23f91d658cb4 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -89,17 +89,10 @@
 /* For higher baud Rates use TIOCEXBAUD */
 #define TIOCEXBAUD     0x5462
 
-/* vendor id and device id defines */
-
-/* The native mos7840/7820 component */
-#define USB_VENDOR_ID_MOSCHIP           0x9710
-#define MOSCHIP_DEVICE_ID_7840          0x7840
-#define MOSCHIP_DEVICE_ID_7843          0x7843
-#define MOSCHIP_DEVICE_ID_7820          0x7820
-#define MOSCHIP_DEVICE_ID_7810          0x7810
-/* The native component can have its vendor/device id's overridden
- * in vendor-specific implementations.  Such devices can be handled
- * by making a change here, in id_table.
+/*
+ * Vendor id and device id defines
+ *
+ * NOTE: Do not add new defines, add entries directly to the id_table instead.
  */
 #define USB_VENDOR_ID_BANDB              0x0856
 #define BANDB_DEVICE_ID_USO9ML2_2        0xAC22
@@ -116,14 +109,6 @@
 #define BANDB_DEVICE_ID_USOPTL4_4P       0xBC03
 #define BANDB_DEVICE_ID_USOPTL2_4        0xAC24
 
-/* This driver also supports
- * ATEN UC2324 device using Moschip MCS7840
- * ATEN UC2322 device using Moschip MCS7820
- */
-#define USB_VENDOR_ID_ATENINTL		0x0557
-#define ATENINTL_DEVICE_ID_UC2324	0x2011
-#define ATENINTL_DEVICE_ID_UC2322	0x7820
-
 /* Interrupt Routine Defines    */
 
 #define SERIAL_IIR_RLS      0x06
@@ -171,30 +156,37 @@
 #define LED_OFF_MS	500
 
 enum mos7840_flag {
-	MOS7840_FLAG_CTRL_BUSY,
 	MOS7840_FLAG_LED_BUSY,
 };
 
+#define MCS_PORT_MASK	GENMASK(2, 0)
+#define MCS_PORTS(nr)	((nr) & MCS_PORT_MASK)
+#define MCS_LED		BIT(3)
+
+#define MCS_DEVICE(vid, pid, flags) \
+		USB_DEVICE((vid), (pid)), .driver_info = (flags)
+
 static const struct usb_device_id id_table[] = {
-	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7840)},
-	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7843)},
-	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7820)},
-	{USB_DEVICE(USB_VENDOR_ID_MOSCHIP, MOSCHIP_DEVICE_ID_7810)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2P)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4P)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_2)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_4)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_2)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_4)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2P)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4P)},
-	{USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL2_4)},
-	{USB_DEVICE(USB_VENDOR_ID_ATENINTL, ATENINTL_DEVICE_ID_UC2324)},
-	{USB_DEVICE(USB_VENDOR_ID_ATENINTL, ATENINTL_DEVICE_ID_UC2322)},
+	{ MCS_DEVICE(0x0557, 0x2011, MCS_PORTS(4)) },	/* ATEN UC2324 */
+	{ MCS_DEVICE(0x0557, 0x7820, MCS_PORTS(2)) },	/* ATEN UC2322 */
+	{ MCS_DEVICE(0x110a, 0x2210, MCS_PORTS(2)) },	/* Moxa UPort 2210 */
+	{ MCS_DEVICE(0x9710, 0x7810, MCS_PORTS(1) | MCS_LED) }, /* ASIX MCS7810 */
+	{ MCS_DEVICE(0x9710, 0x7820, MCS_PORTS(2)) },	/* MosChip MCS7820 */
+	{ MCS_DEVICE(0x9710, 0x7840, MCS_PORTS(4)) },	/* MosChip MCS7840 */
+	{ MCS_DEVICE(0x9710, 0x7843, MCS_PORTS(3)) },	/* ASIX MCS7840 3 port */
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_2P) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USO9ML2_4P) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_2) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_US9ML2_4) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_2) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USPTL4_4) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_2P) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL4_4P) },
+	{ USB_DEVICE(USB_VENDOR_ID_BANDB, BANDB_DEVICE_ID_USOPTL2_4) },
 	{}			/* terminating entry */
 };
 MODULE_DEVICE_TABLE(usb, id_table);
@@ -206,19 +198,12 @@ struct moschip_port {
 	struct urb *read_urb;	/* read URB for this port */
 	__u8 shadowLCR;		/* last LCR value received */
 	__u8 shadowMCR;		/* last MCR value received */
-	char open;
-	char open_ports;
 	struct usb_serial_port *port;	/* loop back to the owner of this object */
 
 	/* Offsets */
 	__u8 SpRegOffset;
 	__u8 ControlRegOffset;
 	__u8 DcrRegOffset;
-	/* for processing control URBS in interrupt context */
-	struct urb *control_urb;
-	struct usb_ctrlrequest *dr;
-	char *ctrl_buf;
-	int MsrLsr;
 
 	spinlock_t pool_lock;
 	struct urb *write_urb_pool[NUM_URBS];
@@ -360,150 +345,11 @@ static void mos7840_dump_serial_port(struct usb_serial_port *port,
 
 /************************************************************************/
 /************************************************************************/
-/*             I N T E R F A C E   F U N C T I O N S			*/
-/*             I N T E R F A C E   F U N C T I O N S			*/
-/************************************************************************/
-/************************************************************************/
-
-static inline void mos7840_set_port_private(struct usb_serial_port *port,
-					    struct moschip_port *data)
-{
-	usb_set_serial_port_data(port, (void *)data);
-}
-
-static inline struct moschip_port *mos7840_get_port_private(struct
-							    usb_serial_port
-							    *port)
-{
-	return (struct moschip_port *)usb_get_serial_port_data(port);
-}
-
-static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr)
-{
-	struct moschip_port *mos7840_port;
-	struct async_icount *icount;
-	mos7840_port = port;
-	if (new_msr &
-	    (MOS_MSR_DELTA_CTS | MOS_MSR_DELTA_DSR | MOS_MSR_DELTA_RI |
-	     MOS_MSR_DELTA_CD)) {
-		icount = &mos7840_port->port->icount;
-
-		/* update input line counters */
-		if (new_msr & MOS_MSR_DELTA_CTS)
-			icount->cts++;
-		if (new_msr & MOS_MSR_DELTA_DSR)
-			icount->dsr++;
-		if (new_msr & MOS_MSR_DELTA_CD)
-			icount->dcd++;
-		if (new_msr & MOS_MSR_DELTA_RI)
-			icount->rng++;
-
-		wake_up_interruptible(&port->port->port.delta_msr_wait);
-	}
-}
-
-static void mos7840_handle_new_lsr(struct moschip_port *port, __u8 new_lsr)
-{
-	struct async_icount *icount;
-
-	if (new_lsr & SERIAL_LSR_BI) {
-		/*
-		 * Parity and Framing errors only count if they
-		 * occur exclusive of a break being
-		 * received.
-		 */
-		new_lsr &= (__u8) (SERIAL_LSR_OE | SERIAL_LSR_BI);
-	}
-
-	/* update input line counters */
-	icount = &port->port->icount;
-	if (new_lsr & SERIAL_LSR_BI)
-		icount->brk++;
-	if (new_lsr & SERIAL_LSR_OE)
-		icount->overrun++;
-	if (new_lsr & SERIAL_LSR_PE)
-		icount->parity++;
-	if (new_lsr & SERIAL_LSR_FE)
-		icount->frame++;
-}
-
-/************************************************************************/
-/************************************************************************/
 /*            U S B  C A L L B A C K   F U N C T I O N S                */
 /*            U S B  C A L L B A C K   F U N C T I O N S                */
 /************************************************************************/
 /************************************************************************/
 
-static void mos7840_control_callback(struct urb *urb)
-{
-	unsigned char *data;
-	struct moschip_port *mos7840_port;
-	struct device *dev = &urb->dev->dev;
-	__u8 regval = 0x0;
-	int status = urb->status;
-
-	mos7840_port = urb->context;
-
-	switch (status) {
-	case 0:
-		/* success */
-		break;
-	case -ECONNRESET:
-	case -ENOENT:
-	case -ESHUTDOWN:
-		/* this urb is terminated, clean up */
-		dev_dbg(dev, "%s - urb shutting down with status: %d\n", __func__, status);
-		goto out;
-	default:
-		dev_dbg(dev, "%s - nonzero urb status received: %d\n", __func__, status);
-		goto out;
-	}
-
-	dev_dbg(dev, "%s urb buffer size is %d\n", __func__, urb->actual_length);
-	if (urb->actual_length < 1)
-		goto out;
-
-	dev_dbg(dev, "%s mos7840_port->MsrLsr is %d port %d\n", __func__,
-		mos7840_port->MsrLsr, mos7840_port->port_num);
-	data = urb->transfer_buffer;
-	regval = (__u8) data[0];
-	dev_dbg(dev, "%s data is %x\n", __func__, regval);
-	if (mos7840_port->MsrLsr == 0)
-		mos7840_handle_new_msr(mos7840_port, regval);
-	else if (mos7840_port->MsrLsr == 1)
-		mos7840_handle_new_lsr(mos7840_port, regval);
-out:
-	clear_bit_unlock(MOS7840_FLAG_CTRL_BUSY, &mos7840_port->flags);
-}
-
-static int mos7840_get_reg(struct moschip_port *mcs, __u16 Wval, __u16 reg,
-			   __u16 *val)
-{
-	struct usb_device *dev = mcs->port->serial->dev;
-	struct usb_ctrlrequest *dr = mcs->dr;
-	unsigned char *buffer = mcs->ctrl_buf;
-	int ret;
-
-	if (test_and_set_bit_lock(MOS7840_FLAG_CTRL_BUSY, &mcs->flags))
-		return -EBUSY;
-
-	dr->bRequestType = MCS_RD_RTYPE;
-	dr->bRequest = MCS_RDREQ;
-	dr->wValue = cpu_to_le16(Wval);	/* 0 */
-	dr->wIndex = cpu_to_le16(reg);
-	dr->wLength = cpu_to_le16(2);
-
-	usb_fill_control_urb(mcs->control_urb, dev, usb_rcvctrlpipe(dev, 0),
-			     (unsigned char *)dr, buffer, 2,
-			     mos7840_control_callback, mcs);
-	mcs->control_urb->transfer_buffer_length = 2;
-	ret = usb_submit_urb(mcs->control_urb, GFP_ATOMIC);
-	if (ret)
-		clear_bit_unlock(MOS7840_FLAG_CTRL_BUSY, &mcs->flags);
-
-	return ret;
-}
-
 static void mos7840_set_led_callback(struct urb *urb)
 {
 	switch (urb->status) {
@@ -580,146 +426,6 @@ static void mos7840_led_activity(struct usb_serial_port *port)
 }
 
 /*****************************************************************************
- * mos7840_interrupt_callback
- *	this is the callback function for when we have received data on the
- *	interrupt endpoint.
- *****************************************************************************/
-
-static void mos7840_interrupt_callback(struct urb *urb)
-{
-	int result;
-	int length;
-	struct moschip_port *mos7840_port;
-	struct usb_serial *serial;
-	__u16 Data;
-	unsigned char *data;
-	__u8 sp[5];
-	int i, rv = 0;
-	__u16 wval, wreg = 0;
-	int status = urb->status;
-
-	switch (status) {
-	case 0:
-		/* success */
-		break;
-	case -ECONNRESET:
-	case -ENOENT:
-	case -ESHUTDOWN:
-		/* this urb is terminated, clean up */
-		dev_dbg(&urb->dev->dev, "%s - urb shutting down with status: %d\n",
-			__func__, status);
-		return;
-	default:
-		dev_dbg(&urb->dev->dev, "%s - nonzero urb status received: %d\n",
-			__func__, status);
-		goto exit;
-	}
-
-	length = urb->actual_length;
-	data = urb->transfer_buffer;
-
-	serial = urb->context;
-
-	/* Moschip get 5 bytes
-	 * Byte 1 IIR Port 1 (port.number is 0)
-	 * Byte 2 IIR Port 2 (port.number is 1)
-	 * Byte 3 IIR Port 3 (port.number is 2)
-	 * Byte 4 IIR Port 4 (port.number is 3)
-	 * Byte 5 FIFO status for both */
-
-	if (length > 5) {
-		dev_dbg(&urb->dev->dev, "%s", "Wrong data !!!\n");
-		return;
-	}
-
-	sp[0] = (__u8) data[0];
-	sp[1] = (__u8) data[1];
-	sp[2] = (__u8) data[2];
-	sp[3] = (__u8) data[3];
-
-	for (i = 0; i < serial->num_ports; i++) {
-		mos7840_port = mos7840_get_port_private(serial->port[i]);
-		wval = ((__u16)serial->port[i]->port_number + 1) << 8;
-		if (mos7840_port->open) {
-			if (sp[i] & 0x01) {
-				dev_dbg(&urb->dev->dev, "SP%d No Interrupt !!!\n", i);
-			} else {
-				switch (sp[i] & 0x0f) {
-				case SERIAL_IIR_RLS:
-					dev_dbg(&urb->dev->dev, "Serial Port %d: Receiver status error or \n", i);
-					dev_dbg(&urb->dev->dev, "address bit detected in 9-bit mode\n");
-					mos7840_port->MsrLsr = 1;
-					wreg = LINE_STATUS_REGISTER;
-					break;
-				case SERIAL_IIR_MS:
-					dev_dbg(&urb->dev->dev, "Serial Port %d: Modem status change\n", i);
-					mos7840_port->MsrLsr = 0;
-					wreg = MODEM_STATUS_REGISTER;
-					break;
-				}
-				rv = mos7840_get_reg(mos7840_port, wval, wreg, &Data);
-			}
-		}
-	}
-	if (!(rv < 0))
-		/* the completion handler for the control urb will resubmit */
-		return;
-exit:
-	result = usb_submit_urb(urb, GFP_ATOMIC);
-	if (result) {
-		dev_err(&urb->dev->dev,
-			"%s - Error %d submitting interrupt urb\n",
-			__func__, result);
-	}
-}
-
-static int mos7840_port_paranoia_check(struct usb_serial_port *port,
-				       const char *function)
-{
-	if (!port) {
-		pr_debug("%s - port == NULL\n", function);
-		return -1;
-	}
-	if (!port->serial) {
-		pr_debug("%s - port->serial == NULL\n", function);
-		return -1;
-	}
-
-	return 0;
-}
-
-/* Inline functions to check the sanity of a pointer that is passed to us */
-static int mos7840_serial_paranoia_check(struct usb_serial *serial,
-					 const char *function)
-{
-	if (!serial) {
-		pr_debug("%s - serial == NULL\n", function);
-		return -1;
-	}
-	if (!serial->type) {
-		pr_debug("%s - serial->type == NULL!\n", function);
-		return -1;
-	}
-
-	return 0;
-}
-
-static struct usb_serial *mos7840_get_usb_serial(struct usb_serial_port *port,
-						 const char *function)
-{
-	/* if no port was specified, or it fails a paranoia check */
-	if (!port ||
-	    mos7840_port_paranoia_check(port, function) ||
-	    mos7840_serial_paranoia_check(port->serial, function)) {
-		/* then say that we don't have a valid usb_serial thing,
-		 * which will end up genrating -ENODEV return values */
-		return NULL;
-	}
-
-	return port->serial;
-}
-
-/*****************************************************************************
  * mos7840_bulk_in_callback
  *	this is the callback function for when we have received data on the
  *	bulk in endpoint.
@@ -727,35 +433,18 @@ static struct usb_serial *mos7840_get_usb_serial(struct usb_serial_port *port,
 
 static void mos7840_bulk_in_callback(struct urb *urb)
 {
+	struct moschip_port *mos7840_port = urb->context;
+	struct usb_serial_port *port = mos7840_port->port;
 	int retval;
 	unsigned char *data;
-	struct usb_serial *serial;
-	struct usb_serial_port *port;
-	struct moschip_port *mos7840_port;
 	int status = urb->status;
 
-	mos7840_port = urb->context;
-	if (!mos7840_port)
-		return;
-
 	if (status) {
 		dev_dbg(&urb->dev->dev, "nonzero read bulk status received: %d\n", status);
 		mos7840_port->read_urb_busy = false;
 		return;
 	}
 
-	port = mos7840_port->port;
-	if (mos7840_port_paranoia_check(port, __func__)) {
-		mos7840_port->read_urb_busy = false;
-		return;
-	}
-
-	serial = mos7840_get_usb_serial(port, __func__);
-	if (!serial) {
-		mos7840_port->read_urb_busy = false;
-		return;
-	}
-
 	data = urb->transfer_buffer;
 	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
 
@@ -767,12 +456,6 @@ static void mos7840_bulk_in_callback(struct urb *urb)
 		dev_dbg(&port->dev, "icount.rx is %d:\n", port->icount.rx);
 	}
 
-	if (!mos7840_port->read_urb) {
-		dev_dbg(&port->dev, "%s", "URB KILLED !!!\n");
-		mos7840_port->read_urb_busy = false;
-		return;
-	}
-
 	if (mos7840_port->has_led)
 		mos7840_led_activity(port);
 
@@ -793,14 +476,12 @@ static void mos7840_bulk_in_callback(struct urb *urb)
 
 static void mos7840_bulk_out_data_callback(struct urb *urb)
 {
-	struct moschip_port *mos7840_port;
-	struct usb_serial_port *port;
+	struct moschip_port *mos7840_port = urb->context;
+	struct usb_serial_port *port = mos7840_port->port;
 	int status = urb->status;
 	unsigned long flags;
 	int i;
 
-	mos7840_port = urb->context;
-	port = mos7840_port->port;
 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
 	for (i = 0; i < NUM_URBS; i++) {
 		if (urb == mos7840_port->write_urb_pool[i]) {
@@ -815,11 +496,7 @@ static void mos7840_bulk_out_data_callback(struct urb *urb)
 		return;
 	}
 
-	if (mos7840_port_paranoia_check(port, __func__))
-		return;
-
-	if (mos7840_port->open)
-		tty_port_tty_wakeup(&port->port);
+	tty_port_tty_wakeup(&port->port);
 
 }
 
@@ -836,32 +513,16 @@ static void mos7840_bulk_out_data_callback(struct urb *urb)
 
 static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
+	struct usb_serial *serial = port->serial;
 	int response;
 	int j;
-	struct usb_serial *serial;
 	struct urb *urb;
 	__u16 Data;
 	int status;
-	struct moschip_port *mos7840_port;
-	struct moschip_port *port0;
-
-	if (mos7840_port_paranoia_check(port, __func__))
-		return -ENODEV;
-
-	serial = port->serial;
-
-	if (mos7840_serial_paranoia_check(serial, __func__))
-		return -ENODEV;
-
-	mos7840_port = mos7840_get_port_private(port);
-	port0 = mos7840_get_port_private(serial->port[0]);
-
-	if (mos7840_port == NULL || port0 == NULL)
-		return -ENODEV;
 
 	usb_clear_halt(serial->dev, port->write_urb->pipe);
 	usb_clear_halt(serial->dev, port->read_urb->pipe);
-	port0->open_ports++;
 
 	/* Initialising the write urb pool */
 	for (j = 0; j < NUM_URBS; ++j) {
@@ -1012,41 +673,6 @@ static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
 	status = mos7840_set_reg_sync(port, mos7840_port->ControlRegOffset,
 									Data);
 
-	/* Check to see if we've set up our endpoint info yet    *
-	 * (can't set it up in mos7840_startup as the structures *
-	 * were not set up at that time.)                        */
-	if (port0->open_ports == 1) {
-		/* FIXME: Buffer never NULL, so URB is not submitted. */
-		if (serial->port[0]->interrupt_in_buffer == NULL) {
-			/* set up interrupt urb */
-			usb_fill_int_urb(serial->port[0]->interrupt_in_urb,
-				serial->dev,
-				usb_rcvintpipe(serial->dev,
-				serial->port[0]->interrupt_in_endpointAddress),
-				serial->port[0]->interrupt_in_buffer,
-				serial->port[0]->interrupt_in_urb->
-				transfer_buffer_length,
-				mos7840_interrupt_callback,
-				serial,
-				serial->port[0]->interrupt_in_urb->interval);
-
-			/* start interrupt read for mos7840 */
-			response =
-			    usb_submit_urb(serial->port[0]->interrupt_in_urb,
-					   GFP_KERNEL);
-			if (response) {
-				dev_err(&port->dev, "%s - Error %d submitting "
-					"interrupt urb\n", __func__, response);
-			}
-
-		}
-
-	}
-
-	/* see if we've set up our endpoint info yet   *
-	 * (can't set it up in mos7840_startup as the  *
-	 * structures were not set up at that time.)   */
-
 	dev_dbg(&port->dev, "port number is %d\n", port->port_number);
 	dev_dbg(&port->dev, "minor number is %d\n", port->minor);
 	dev_dbg(&port->dev, "Bulkin endpoint is %d\n", port->bulk_in_endpointAddress);
@@ -1086,9 +712,6 @@ static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port)
 	/* initialize our port settings */
 	/* Must set to enable ints! */
 	mos7840_port->shadowMCR = MCR_MASTER_IE;
-	/* send a open port command */
-	mos7840_port->open = 1;
-	/* mos7840_change_port_settings(mos7840_port,old_termios); */
 
 	return 0;
 err:
@@ -1115,17 +738,10 @@ err:
 static int mos7840_chars_in_buffer(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 	int i;
 	int chars = 0;
 	unsigned long flags;
-	struct moschip_port *mos7840_port;
-
-	if (mos7840_port_paranoia_check(port, __func__))
-		return 0;
-
-	mos7840_port = mos7840_get_port_private(port);
-	if (mos7840_port == NULL)
-		return 0;
 
 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
 	for (i = 0; i < NUM_URBS; ++i) {
@@ -1147,25 +763,10 @@ static int mos7840_chars_in_buffer(struct tty_struct *tty)
 
 static void mos7840_close(struct usb_serial_port *port)
 {
-	struct usb_serial *serial;
-	struct moschip_port *mos7840_port;
-	struct moschip_port *port0;
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 	int j;
 	__u16 Data;
 
-	if (mos7840_port_paranoia_check(port, __func__))
-		return;
-
-	serial = mos7840_get_usb_serial(port, __func__);
-	if (!serial)
-		return;
-
-	mos7840_port = mos7840_get_port_private(port);
-	port0 = mos7840_get_port_private(serial->port[0]);
-
-	if (mos7840_port == NULL || port0 == NULL)
-		return;
-
 	for (j = 0; j < NUM_URBS; ++j)
 		usb_kill_urb(mos7840_port->write_urb_pool[j]);
 
@@ -1180,22 +781,11 @@ static void mos7840_close(struct usb_serial_port *port)
 	usb_kill_urb(mos7840_port->read_urb);
 	mos7840_port->read_urb_busy = false;
 
-	port0->open_ports--;
-	dev_dbg(&port->dev, "%s in close%d\n", __func__, port0->open_ports);
-	if (port0->open_ports == 0) {
-		if (serial->port[0]->interrupt_in_urb) {
-			dev_dbg(&port->dev, "Shutdown interrupt_in_urb\n");
-			usb_kill_urb(serial->port[0]->interrupt_in_urb);
-		}
-	}
-
 	Data = 0x0;
 	mos7840_set_uart_reg(port, MODEM_CONTROL_REGISTER, Data);
 
 	Data = 0x00;
 	mos7840_set_uart_reg(port, INTERRUPT_ENABLE_REGISTER, Data);
-
-	mos7840_port->open = 0;
 }
 
 /*****************************************************************************
@@ -1205,21 +795,8 @@ static void mos7840_close(struct usb_serial_port *port)
 static void mos7840_break(struct tty_struct *tty, int break_state)
 {
 	struct usb_serial_port *port = tty->driver_data;
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 	unsigned char data;
-	struct usb_serial *serial;
-	struct moschip_port *mos7840_port;
-
-	if (mos7840_port_paranoia_check(port, __func__))
-		return;
-
-	serial = mos7840_get_usb_serial(port, __func__);
-	if (!serial)
-		return;
-
-	mos7840_port = mos7840_get_port_private(port);
-
-	if (mos7840_port == NULL)
-		return;
 
 	if (break_state == -1)
 		data = mos7840_port->shadowLCR | LCR_SET_BREAK;
@@ -1244,17 +821,10 @@ static void mos7840_break(struct tty_struct *tty, int break_state)
 static int mos7840_write_room(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 	int i;
 	int room = 0;
 	unsigned long flags;
-	struct moschip_port *mos7840_port;
-
-	if (mos7840_port_paranoia_check(port, __func__))
-		return -1;
-
-	mos7840_port = mos7840_get_port_private(port);
-	if (mos7840_port == NULL)
-		return -1;
 
 	spin_lock_irqsave(&mos7840_port->pool_lock, flags);
 	for (i = 0; i < NUM_URBS; ++i) {
@@ -1280,29 +850,17 @@ static int mos7840_write_room(struct tty_struct *tty)
 static int mos7840_write(struct tty_struct *tty, struct usb_serial_port *port,
 			 const unsigned char *data, int count)
 {
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
+	struct usb_serial *serial = port->serial;
 	int status;
 	int i;
 	int bytes_sent = 0;
 	int transfer_size;
 	unsigned long flags;
-
-	struct moschip_port *mos7840_port;
-	struct usb_serial *serial;
 	struct urb *urb;
 	/* __u16 Data; */
 	const unsigned char *current_position = data;
 
-	if (mos7840_port_paranoia_check(port, __func__))
-		return -1;
-
-	serial = port->serial;
-	if (mos7840_serial_paranoia_check(serial, __func__))
-		return -1;
-
-	mos7840_port = mos7840_get_port_private(port);
-	if (mos7840_port == NULL)
-		return -1;
-
 	/* try to find a free urb in the list */
 	urb = NULL;
 
@@ -1383,22 +941,9 @@ exit:
 static void mos7840_throttle(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
-	struct moschip_port *mos7840_port;
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 	int status;
 
-	if (mos7840_port_paranoia_check(port, __func__))
-		return;
-
-	mos7840_port = mos7840_get_port_private(port);
-
-	if (mos7840_port == NULL)
-		return;
-
-	if (!mos7840_port->open) {
-		dev_dbg(&port->dev, "%s", "port not opened\n");
-		return;
-	}
-
 	/* if we are implementing XON/XOFF, send the stop character */
 	if (I_IXOFF(tty)) {
 		unsigned char stop_char = STOP_CHAR(tty);
@@ -1425,19 +970,8 @@ static void mos7840_throttle(struct tty_struct *tty)
 static void mos7840_unthrottle(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 	int status;
-	struct moschip_port *mos7840_port = mos7840_get_port_private(port);
-
-	if (mos7840_port_paranoia_check(port, __func__))
-		return;
-
-	if (mos7840_port == NULL)
-		return;
-
-	if (!mos7840_port->open) {
-		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
-		return;
-	}
 
 	/* if we are implementing XON/XOFF, send the start character */
 	if (I_IXOFF(tty)) {
@@ -1460,15 +994,10 @@ static void mos7840_unthrottle(struct tty_struct *tty)
 static int mos7840_tiocmget(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
-	struct moschip_port *mos7840_port;
 	unsigned int result;
 	__u16 msr;
 	__u16 mcr;
 	int status;
-	mos7840_port = mos7840_get_port_private(port);
-
-	if (mos7840_port == NULL)
-		return -ENODEV;
 
 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
 	if (status < 0)
@@ -1493,15 +1022,10 @@ static int mos7840_tiocmset(struct tty_struct *tty,
 			    unsigned int set, unsigned int clear)
 {
 	struct usb_serial_port *port = tty->driver_data;
-	struct moschip_port *mos7840_port;
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 	unsigned int mcr;
 	int status;
 
-	mos7840_port = mos7840_get_port_private(port);
-
-	if (mos7840_port == NULL)
-		return -ENODEV;
-
 	/* FIXME: What locks the port registers ? */
 	mcr = mos7840_port->shadowMCR;
 	if (clear & TIOCM_RTS)
@@ -1578,21 +1102,11 @@ static int mos7840_calc_baud_rate_divisor(struct usb_serial_port *port,
 static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
 					    int baudRate)
 {
+	struct usb_serial_port *port = mos7840_port->port;
 	int divisor = 0;
 	int status;
 	__u16 Data;
 	__u16 clk_sel_val;
-	struct usb_serial_port *port;
-
-	if (mos7840_port == NULL)
-		return -1;
-
-	port = mos7840_port->port;
-	if (mos7840_port_paranoia_check(port, __func__))
-		return -1;
-
-	if (mos7840_serial_paranoia_check(port->serial, __func__))
-		return -1;
 
 	dev_dbg(&port->dev, "%s - baud = %d\n", __func__, baudRate);
 	/* reset clk_uart_sel in spregOffset */
@@ -1681,6 +1195,7 @@ static int mos7840_send_cmd_write_baud_rate(struct moschip_port *mos7840_port,
 static void mos7840_change_port_settings(struct tty_struct *tty,
 	struct moschip_port *mos7840_port, struct ktermios *old_termios)
 {
+	struct usb_serial_port *port = mos7840_port->port;
 	int baud;
 	unsigned cflag;
 	__u8 lData;
@@ -1688,23 +1203,6 @@ static void mos7840_change_port_settings(struct tty_struct *tty,
 	__u8 lStop;
 	int status;
 	__u16 Data;
-	struct usb_serial_port *port;
-
-	if (mos7840_port == NULL)
-		return;
-
-	port = mos7840_port->port;
-
-	if (mos7840_port_paranoia_check(port, __func__))
-		return;
-
-	if (mos7840_serial_paranoia_check(port->serial, __func__))
-		return;
-
-	if (!mos7840_port->open) {
-		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
-		return;
-	}
 
 	lData = LCR_BITS_8;
 	lStop = LCR_STOP_1;
@@ -1839,37 +1337,13 @@ static void mos7840_set_termios(struct tty_struct *tty,
 				struct usb_serial_port *port,
 				struct ktermios *old_termios)
 {
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 	int status;
-	struct usb_serial *serial;
-	struct moschip_port *mos7840_port;
-
-	if (mos7840_port_paranoia_check(port, __func__))
-		return;
-
-	serial = port->serial;
-
-	if (mos7840_serial_paranoia_check(serial, __func__))
-		return;
-
-	mos7840_port = mos7840_get_port_private(port);
-
-	if (mos7840_port == NULL)
-		return;
-
-	if (!mos7840_port->open) {
-		dev_dbg(&port->dev, "%s - port not opened\n", __func__);
-		return;
-	}
 
 	/* change the port settings to the new ones specified */
 
 	mos7840_change_port_settings(tty, mos7840_port, old_termios);
 
-	if (!mos7840_port->read_urb) {
-		dev_dbg(&port->dev, "%s", "URB KILLED !!!!!\n");
-		return;
-	}
-
 	if (!mos7840_port->read_urb_busy) {
 		mos7840_port->read_urb_busy = true;
 		status = usb_submit_urb(mos7840_port->read_urb, GFP_KERNEL);
@@ -1916,7 +1390,7 @@ static int mos7840_get_serial_info(struct tty_struct *tty,
 				   struct serial_struct *ss)
 {
 	struct usb_serial_port *port = tty->driver_data;
-	struct moschip_port *mos7840_port = mos7840_get_port_private(port);
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 
 	ss->type = PORT_16550A;
 	ss->line = mos7840_port->port->minor;
@@ -1939,15 +1413,6 @@ static int mos7840_ioctl(struct tty_struct *tty,
 {
 	struct usb_serial_port *port = tty->driver_data;
 	void __user *argp = (void __user *)arg;
-	struct moschip_port *mos7840_port;
-
-	if (mos7840_port_paranoia_check(port, __func__))
-		return -1;
-
-	mos7840_port = mos7840_get_port_private(port);
-
-	if (mos7840_port == NULL)
-		return -1;
 
 	switch (cmd) {
 		/* return number of bytes available */
@@ -1962,6 +1427,13 @@ static int mos7840_ioctl(struct tty_struct *tty,
 	return -ENOIOCTLCMD;
 }
 
+/*
+ * Check if GPO (pin 42) is connected to GPI (pin 33) as recommended by ASIX
+ * for MCS7810 by bit-banging a 16-bit word.
+ *
+ * Note that GPO is really RTS of the third port so this will toggle RTS of
+ * port two or three on two- and four-port devices.
+ */
 static int mos7810_check(struct usb_serial *serial)
 {
 	int i, pass_count = 0;
@@ -2019,16 +1491,12 @@ static int mos7810_check(struct usb_serial *serial)
 static int mos7840_probe(struct usb_serial *serial,
 				const struct usb_device_id *id)
 {
-	u16 product = le16_to_cpu(serial->dev->descriptor.idProduct);
+	unsigned long device_flags = id->driver_info;
 	u8 *buf;
-	int device_type;
 
-	if (product == MOSCHIP_DEVICE_ID_7810 ||
-		product == MOSCHIP_DEVICE_ID_7820 ||
-		product == MOSCHIP_DEVICE_ID_7843) {
-		device_type = product;
+	/* Skip device-type detection if we already have device flags. */
+	if (device_flags)
 		goto out;
-	}
 
 	buf = kzalloc(VENDOR_READ_LENGTH, GFP_KERNEL);
 	if (!buf)
@@ -2040,15 +1508,15 @@ static int mos7840_probe(struct usb_serial *serial,
 
 	/* For a MCS7840 device GPIO0 must be set to 1 */
 	if (buf[0] & 0x01)
-		device_type = MOSCHIP_DEVICE_ID_7840;
+		device_flags = MCS_PORTS(4);
 	else if (mos7810_check(serial))
-		device_type = MOSCHIP_DEVICE_ID_7810;
+		device_flags = MCS_PORTS(1) | MCS_LED;
 	else
-		device_type = MOSCHIP_DEVICE_ID_7820;
+		device_flags = MCS_PORTS(2);
 
 	kfree(buf);
 out:
-	usb_set_serial_data(serial, (void *)(unsigned long)device_type);
+	usb_set_serial_data(serial, (void *)device_flags);
 
 	return 0;
 }
@@ -2056,19 +1524,10 @@ out:
 static int mos7840_calc_num_ports(struct usb_serial *serial,
 					struct usb_serial_endpoints *epds)
 {
-	int device_type = (unsigned long)usb_get_serial_data(serial);
-	int num_ports;
+	unsigned long device_flags = (unsigned long)usb_get_serial_data(serial);
+	int num_ports = MCS_PORTS(device_flags);
 
-	if (device_type == MOSCHIP_DEVICE_ID_7843)
-		num_ports = 3;
-	else
-		num_ports = (device_type >> 4) & 0x000F;
-
-	/*
-	 * num_ports is currently never zero as device_type is one of
-	 * MOSCHIP_DEVICE_ID_78{1,2,4}0.
-	 */
-	if (num_ports == 0)
+	if (num_ports == 0 || num_ports > 4)
 		return -ENODEV;
 
 	if (epds->num_bulk_in < num_ports || epds->num_bulk_out < num_ports) {
@@ -2079,10 +1538,27 @@ static int mos7840_calc_num_ports(struct usb_serial *serial,
 	return num_ports;
 }
 
+static int mos7840_attach(struct usb_serial *serial)
+{
+	struct device *dev = &serial->interface->dev;
+	int status;
+	u16 val;
+
+	/* Zero Length flag enable */
+	val = 0x0f;
+	status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, val);
+	if (status < 0)
+		dev_dbg(dev, "Writing ZLP_REG5 failed status-0x%x\n", status);
+	else
+		dev_dbg(dev, "ZLP_REG5 Writing success status%d\n", status);
+
+	return status;
+}
+
 static int mos7840_port_probe(struct usb_serial_port *port)
 {
 	struct usb_serial *serial = port->serial;
-	int device_type = (unsigned long)usb_get_serial_data(serial);
+	unsigned long device_flags = (unsigned long)usb_get_serial_data(serial);
 	struct moschip_port *mos7840_port;
 	int status;
 	int pnum;
@@ -2103,7 +1579,6 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 	 * common to all port */
 
 	mos7840_port->port = port;
-	mos7840_set_port_private(port, mos7840_port);
 	spin_lock_init(&mos7840_port->pool_lock);
 
 	/* minor is not initialised until later by
@@ -2129,14 +1604,14 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 		mos7840_port->DcrRegOffset = 0x16 + 3 * (phy_num - 2);
 	}
 	mos7840_dump_serial_port(port, mos7840_port);
-	mos7840_set_port_private(port, mos7840_port);
+	usb_set_serial_port_data(port, mos7840_port);
 
 	/* enable rx_disable bit in control register */
 	status = mos7840_get_reg_sync(port,
 			mos7840_port->ControlRegOffset, &Data);
 	if (status < 0) {
 		dev_dbg(&port->dev, "Reading ControlReg failed status-0x%x\n", status);
-		goto out;
+		goto error;
 	} else
 		dev_dbg(&port->dev, "ControlReg Reading success val is %x, status%d\n", Data, status);
 	Data |= 0x08;	/* setting driver done bit */
@@ -2148,7 +1623,7 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 			mos7840_port->ControlRegOffset, Data);
 	if (status < 0) {
 		dev_dbg(&port->dev, "Writing ControlReg failed(rx_disable) status-0x%x\n", status);
-		goto out;
+		goto error;
 	} else
 		dev_dbg(&port->dev, "ControlReg Writing success(rx_disable) status%d\n", status);
 
@@ -2159,7 +1634,7 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 			(__u16) (mos7840_port->DcrRegOffset + 0), Data);
 	if (status < 0) {
 		dev_dbg(&port->dev, "Writing DCR0 failed status-0x%x\n", status);
-		goto out;
+		goto error;
 	} else
 		dev_dbg(&port->dev, "DCR0 Writing success status%d\n", status);
 
@@ -2168,7 +1643,7 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 			(__u16) (mos7840_port->DcrRegOffset + 1), Data);
 	if (status < 0) {
 		dev_dbg(&port->dev, "Writing DCR1 failed status-0x%x\n", status);
-		goto out;
+		goto error;
 	} else
 		dev_dbg(&port->dev, "DCR1 Writing success status%d\n", status);
 
@@ -2177,7 +1652,7 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 			(__u16) (mos7840_port->DcrRegOffset + 2), Data);
 	if (status < 0) {
 		dev_dbg(&port->dev, "Writing DCR2 failed status-0x%x\n", status);
-		goto out;
+		goto error;
 	} else
 		dev_dbg(&port->dev, "DCR2 Writing success status%d\n", status);
 
@@ -2186,7 +1661,7 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 	status = mos7840_set_reg_sync(port, CLK_START_VALUE_REGISTER, Data);
 	if (status < 0) {
 		dev_dbg(&port->dev, "Writing CLK_START_VALUE_REGISTER failed status-0x%x\n", status);
-		goto out;
+		goto error;
 	} else
 		dev_dbg(&port->dev, "CLK_START_VALUE_REGISTER Writing success status%d\n", status);
 
@@ -2203,7 +1678,7 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 	status = mos7840_set_uart_reg(port, SCRATCH_PAD_REGISTER, Data);
 	if (status < 0) {
 		dev_dbg(&port->dev, "Writing SCRATCH_PAD_REGISTER failed status-0x%x\n", status);
-		goto out;
+		goto error;
 	} else
 		dev_dbg(&port->dev, "SCRATCH_PAD_REGISTER Writing success status%d\n", status);
 
@@ -2217,7 +1692,7 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num)));
 		if (status < 0) {
 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 2, status);
-			goto out;
+			goto error;
 		} else
 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 2, status);
 	} else {
@@ -2229,27 +1704,16 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 				(__u16)(ZLP_REG1 + ((__u16) mos7840_port->port_num) - 0x1));
 		if (status < 0) {
 			dev_dbg(&port->dev, "Writing ZLP_REG%d failed status-0x%x\n", pnum + 1, status);
-			goto out;
+			goto error;
 		} else
 			dev_dbg(&port->dev, "ZLP_REG%d Writing success status%d\n", pnum + 1, status);
 
 	}
-	mos7840_port->control_urb = usb_alloc_urb(0, GFP_KERNEL);
-	mos7840_port->ctrl_buf = kmalloc(16, GFP_KERNEL);
-	mos7840_port->dr = kmalloc(sizeof(struct usb_ctrlrequest),
-			GFP_KERNEL);
-	if (!mos7840_port->control_urb || !mos7840_port->ctrl_buf ||
-			!mos7840_port->dr) {
-		status = -ENOMEM;
-		goto error;
-	}
 
-	mos7840_port->has_led = false;
+	mos7840_port->has_led = device_flags & MCS_LED;
 
 	/* Initialize LED timers */
-	if (device_type == MOSCHIP_DEVICE_ID_7810) {
-		mos7840_port->has_led = true;
-
+	if (mos7840_port->has_led) {
 		mos7840_port->led_urb = usb_alloc_urb(0, GFP_KERNEL);
 		mos7840_port->led_dr = kmalloc(sizeof(*mos7840_port->led_dr),
 								GFP_KERNEL);
@@ -2269,29 +1733,11 @@ static int mos7840_port_probe(struct usb_serial_port *port)
 		/* Turn off LED */
 		mos7840_set_led_sync(port, MODEM_CONTROL_REGISTER, 0x0300);
 	}
-out:
-	if (pnum == serial->num_ports - 1) {
-		/* Zero Length flag enable */
-		Data = 0x0f;
-		status = mos7840_set_reg_sync(serial->port[0], ZLP_REG5, Data);
-		if (status < 0) {
-			dev_dbg(&port->dev, "Writing ZLP_REG5 failed status-0x%x\n", status);
-			goto error;
-		} else
-			dev_dbg(&port->dev, "ZLP_REG5 Writing success status%d\n", status);
 
-		/* setting configuration feature to one */
-		usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-				0x03, 0x00, 0x01, 0x00, NULL, 0x00,
-				MOS_WDR_TIMEOUT);
-	}
 	return 0;
 error:
 	kfree(mos7840_port->led_dr);
 	usb_free_urb(mos7840_port->led_urb);
-	kfree(mos7840_port->dr);
-	kfree(mos7840_port->ctrl_buf);
-	usb_free_urb(mos7840_port->control_urb);
 	kfree(mos7840_port);
 
 	return status;
@@ -2299,9 +1745,7 @@ error:
 
 static int mos7840_port_remove(struct usb_serial_port *port)
 {
-	struct moschip_port *mos7840_port;
-
-	mos7840_port = mos7840_get_port_private(port);
+	struct moschip_port *mos7840_port = usb_get_serial_port_data(port);
 
 	if (mos7840_port->has_led) {
 		/* Turn off LED */
@@ -2314,10 +1758,7 @@ static int mos7840_port_remove(struct usb_serial_port *port)
 		usb_free_urb(mos7840_port->led_urb);
 		kfree(mos7840_port->led_dr);
 	}
-	usb_kill_urb(mos7840_port->control_urb);
-	usb_free_urb(mos7840_port->control_urb);
-	kfree(mos7840_port->ctrl_buf);
-	kfree(mos7840_port->dr);
+
 	kfree(mos7840_port);
 
 	return 0;
@@ -2340,18 +1781,17 @@ static struct usb_serial_driver moschip7840_4port_device = {
 	.unthrottle = mos7840_unthrottle,
 	.calc_num_ports = mos7840_calc_num_ports,
 	.probe = mos7840_probe,
+	.attach = mos7840_attach,
 	.ioctl = mos7840_ioctl,
 	.get_serial = mos7840_get_serial_info,
 	.set_termios = mos7840_set_termios,
 	.break_ctl = mos7840_break,
 	.tiocmget = mos7840_tiocmget,
 	.tiocmset = mos7840_tiocmset,
-	.tiocmiwait = usb_serial_generic_tiocmiwait,
 	.get_icount = usb_serial_generic_get_icount,
 	.port_probe = mos7840_port_probe,
 	.port_remove = mos7840_port_remove,
 	.read_bulk_callback = mos7840_bulk_in_callback,
-	.read_int_callback = mos7840_interrupt_callback,
 };
 
 static struct usb_serial_driver * const serial_drivers[] = {
diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index 06ab016be0b6..e9491d400a24 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -197,6 +197,7 @@ static void option_instat_callback(struct urb *urb);
 #define DELL_PRODUCT_5804_MINICARD_ATT		0x819b  /* Novatel E371 */
 
 #define DELL_PRODUCT_5821E			0x81d7
+#define DELL_PRODUCT_5821E_ESIM			0x81e0
 
 #define KYOCERA_VENDOR_ID			0x0c88
 #define KYOCERA_PRODUCT_KPC650			0x17da
@@ -1044,6 +1045,8 @@ static const struct usb_device_id option_ids[] = {
 	{ USB_DEVICE_AND_INTERFACE_INFO(DELL_VENDOR_ID, DELL_PRODUCT_5804_MINICARD_ATT, 0xff, 0xff, 0xff) },
 	{ USB_DEVICE(DELL_VENDOR_ID, DELL_PRODUCT_5821E),
 	  .driver_info = RSVD(0) | RSVD(1) | RSVD(6) },
+	{ USB_DEVICE(DELL_VENDOR_ID, DELL_PRODUCT_5821E_ESIM),
+	  .driver_info = RSVD(0) | RSVD(1) | RSVD(6) },
 	{ USB_DEVICE(ANYDATA_VENDOR_ID, ANYDATA_PRODUCT_ADU_E100A) },	/* ADU-E100, ADU-310 */
 	{ USB_DEVICE(ANYDATA_VENDOR_ID, ANYDATA_PRODUCT_ADU_500A) },
 	{ USB_DEVICE(ANYDATA_VENDOR_ID, ANYDATA_PRODUCT_ADU_620UW) },
@@ -1990,6 +1993,10 @@ static const struct usb_device_id option_ids[] = {
 	{ USB_DEVICE_AND_INTERFACE_INFO(0x03f0, 0xa31d, 0xff, 0x06, 0x13) },
 	{ USB_DEVICE_AND_INTERFACE_INFO(0x03f0, 0xa31d, 0xff, 0x06, 0x14) },
 	{ USB_DEVICE_AND_INTERFACE_INFO(0x03f0, 0xa31d, 0xff, 0x06, 0x1b) },
+	{ USB_DEVICE(0x0489, 0xe0b4),						/* Foxconn T77W968 */
+	  .driver_info = RSVD(0) | RSVD(1) | RSVD(6) },
+	{ USB_DEVICE(0x0489, 0xe0b5),						/* Foxconn T77W968 ESIM */
+	  .driver_info = RSVD(0) | RSVD(1) | RSVD(6) },
 	{ USB_DEVICE(0x1508, 0x1001),						/* Fibocom NL668 */
 	  .driver_info = RSVD(4) | RSVD(5) | RSVD(6) },
 	{ USB_DEVICE(0x2cb7, 0x0104),						/* Fibocom NL678 series */
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 9d27b76c5c6e..aab737e1e7b6 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -47,6 +47,12 @@ static const struct usb_device_id id_table[] = {
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MOTOROLA) },
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ZTEK) },
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_TB) },
+	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GC) },
+	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GB) },
+	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GT) },
+	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GL) },
+	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GE) },
+	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GS) },
 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID_RSAQ5) },
 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID),
@@ -130,9 +136,11 @@ MODULE_DEVICE_TABLE(usb, id_table);
 
 #define VENDOR_WRITE_REQUEST_TYPE	0x40
 #define VENDOR_WRITE_REQUEST		0x01
+#define VENDOR_WRITE_NREQUEST		0x80
 
 #define VENDOR_READ_REQUEST_TYPE	0xc0
 #define VENDOR_READ_REQUEST		0x01
+#define VENDOR_READ_NREQUEST		0x81
 
 #define UART_STATE_INDEX		8
 #define UART_STATE_MSR_MASK		0x8b
@@ -148,11 +156,24 @@ MODULE_DEVICE_TABLE(usb, id_table);
 
 #define PL2303_FLOWCTRL_MASK		0xf0
 
+#define PL2303_READ_TYPE_HX_STATUS	0x8080
+
+#define PL2303_HXN_RESET_REG		0x07
+#define PL2303_HXN_RESET_UPSTREAM_PIPE	0x02
+#define PL2303_HXN_RESET_DOWNSTREAM_PIPE	0x01
+
+#define PL2303_HXN_FLOWCTRL_REG		0x0a
+#define PL2303_HXN_FLOWCTRL_MASK	0x1c
+#define PL2303_HXN_FLOWCTRL_NONE	0x1c
+#define PL2303_HXN_FLOWCTRL_RTS_CTS	0x18
+#define PL2303_HXN_FLOWCTRL_XON_XOFF	0x0c
+
 static void pl2303_set_break(struct usb_serial_port *port, bool enable);
 
 enum pl2303_type {
 	TYPE_01,	/* Type 0 and 1 (difference unknown) */
 	TYPE_HX,	/* HX version of the pl2303 chip */
+	TYPE_HXN,	/* HXN version of the pl2303 chip */
 	TYPE_COUNT
 };
 
@@ -184,16 +205,26 @@ static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
 	[TYPE_HX] = {
 		.max_baud_rate		= 12000000,
 	},
+	[TYPE_HXN] = {
+		.max_baud_rate		= 12000000,
+	},
 };
 
 static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
 							unsigned char buf[1])
 {
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 	struct device *dev = &serial->interface->dev;
+	u8 request;
 	int res;
 
+	if (spriv->type == &pl2303_type_data[TYPE_HXN])
+		request = VENDOR_READ_NREQUEST;
+	else
+		request = VENDOR_READ_REQUEST;
+
 	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
-			VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
+			request, VENDOR_READ_REQUEST_TYPE,
 			value, 0, buf, 1, 100);
 	if (res != 1) {
 		dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
@@ -211,13 +242,20 @@ static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
 
 static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
 {
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 	struct device *dev = &serial->interface->dev;
+	u8 request;
 	int res;
 
 	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
 
+	if (spriv->type == &pl2303_type_data[TYPE_HXN])
+		request = VENDOR_WRITE_NREQUEST;
+	else
+		request = VENDOR_WRITE_REQUEST;
+
 	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-			VENDOR_WRITE_REQUEST, VENDOR_WRITE_REQUEST_TYPE,
+			request, VENDOR_WRITE_REQUEST_TYPE,
 			value, index, NULL, 0, 100);
 	if (res) {
 		dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
@@ -230,6 +268,7 @@ static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
 
 static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val)
 {
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 	int ret = 0;
 	u8 *buf;
 
@@ -237,7 +276,11 @@ static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val)
 	if (!buf)
 		return -ENOMEM;
 
-	ret = pl2303_vendor_read(serial, reg | 0x80, buf);
+	if (spriv->type == &pl2303_type_data[TYPE_HXN])
+		ret = pl2303_vendor_read(serial, reg, buf);
+	else
+		ret = pl2303_vendor_read(serial, reg | 0x80, buf);
+
 	if (ret)
 		goto out_free;
 
@@ -320,6 +363,7 @@ static int pl2303_startup(struct usb_serial *serial)
 	struct pl2303_serial_private *spriv;
 	enum pl2303_type type = TYPE_01;
 	unsigned char *buf;
+	int res;
 
 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
 	if (!spriv)
@@ -341,26 +385,37 @@ static int pl2303_startup(struct usb_serial *serial)
 		type = TYPE_01;		/* type 1 */
 	dev_dbg(&serial->interface->dev, "device type: %d\n", type);
 
+	if (type == TYPE_HX) {
+		res = usb_control_msg(serial->dev,
+				usb_rcvctrlpipe(serial->dev, 0),
+				VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
+				PL2303_READ_TYPE_HX_STATUS, 0, buf, 1, 100);
+		if (res != 1)
+			type = TYPE_HXN;
+	}
+
 	spriv->type = &pl2303_type_data[type];
 	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
 	spriv->quirks |= spriv->type->quirks;
 
 	usb_set_serial_data(serial, spriv);
 
-	pl2303_vendor_read(serial, 0x8484, buf);
-	pl2303_vendor_write(serial, 0x0404, 0);
-	pl2303_vendor_read(serial, 0x8484, buf);
-	pl2303_vendor_read(serial, 0x8383, buf);
-	pl2303_vendor_read(serial, 0x8484, buf);
-	pl2303_vendor_write(serial, 0x0404, 1);
-	pl2303_vendor_read(serial, 0x8484, buf);
-	pl2303_vendor_read(serial, 0x8383, buf);
-	pl2303_vendor_write(serial, 0, 1);
-	pl2303_vendor_write(serial, 1, 0);
-	if (spriv->quirks & PL2303_QUIRK_LEGACY)
-		pl2303_vendor_write(serial, 2, 0x24);
-	else
-		pl2303_vendor_write(serial, 2, 0x44);
+	if (type != TYPE_HXN) {
+		pl2303_vendor_read(serial, 0x8484, buf);
+		pl2303_vendor_write(serial, 0x0404, 0);
+		pl2303_vendor_read(serial, 0x8484, buf);
+		pl2303_vendor_read(serial, 0x8383, buf);
+		pl2303_vendor_read(serial, 0x8484, buf);
+		pl2303_vendor_write(serial, 0x0404, 1);
+		pl2303_vendor_read(serial, 0x8484, buf);
+		pl2303_vendor_read(serial, 0x8383, buf);
+		pl2303_vendor_write(serial, 0, 1);
+		pl2303_vendor_write(serial, 1, 0);
+		if (spriv->quirks & PL2303_QUIRK_LEGACY)
+			pl2303_vendor_write(serial, 2, 0x24);
+		else
+			pl2303_vendor_write(serial, 2, 0x44);
+	}
 
 	kfree(buf);
 
@@ -719,14 +774,31 @@ static void pl2303_set_termios(struct tty_struct *tty,
 	}
 
 	if (C_CRTSCTS(tty)) {
-		if (spriv->quirks & PL2303_QUIRK_LEGACY)
+		if (spriv->quirks & PL2303_QUIRK_LEGACY) {
 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40);
-		else
+		} else if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
+			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
+					PL2303_HXN_FLOWCTRL_MASK,
+					PL2303_HXN_FLOWCTRL_RTS_CTS);
+		} else {
 			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x60);
+		}
 	} else if (pl2303_enable_xonxoff(tty, spriv->type)) {
-		pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0);
+		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
+			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
+					PL2303_HXN_FLOWCTRL_MASK,
+					PL2303_HXN_FLOWCTRL_XON_XOFF);
+		} else {
+			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0);
+		}
 	} else {
-		pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
+		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
+			pl2303_update_reg(serial, PL2303_HXN_FLOWCTRL_REG,
+					PL2303_HXN_FLOWCTRL_MASK,
+					PL2303_HXN_FLOWCTRL_NONE);
+		} else {
+			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
+		}
 	}
 
 	kfree(buf);
@@ -767,8 +839,14 @@ static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 		usb_clear_halt(serial->dev, port->read_urb->pipe);
 	} else {
 		/* reset upstream data pipes */
-		pl2303_vendor_write(serial, 8, 0);
-		pl2303_vendor_write(serial, 9, 0);
+		if (spriv->type == &pl2303_type_data[TYPE_HXN]) {
+			pl2303_vendor_write(serial, PL2303_HXN_RESET_REG,
+					PL2303_HXN_RESET_UPSTREAM_PIPE |
+					PL2303_HXN_RESET_DOWNSTREAM_PIPE);
+		} else {
+			pl2303_vendor_write(serial, 8, 0);
+			pl2303_vendor_write(serial, 9, 0);
+		}
 	}
 
 	/* Setup termios */
diff --git a/drivers/usb/serial/pl2303.h b/drivers/usb/serial/pl2303.h
index b0175f17d1a2..a019ea7e6e0e 100644
--- a/drivers/usb/serial/pl2303.h
+++ b/drivers/usb/serial/pl2303.h
@@ -9,6 +9,12 @@
 #define PL2303_VENDOR_ID	0x067b
 #define PL2303_PRODUCT_ID	0x2303
 #define PL2303_PRODUCT_ID_TB		0x2304
+#define PL2303_PRODUCT_ID_GC		0x23a3
+#define PL2303_PRODUCT_ID_GB		0x23b3
+#define PL2303_PRODUCT_ID_GT		0x23c3
+#define PL2303_PRODUCT_ID_GL		0x23d3
+#define PL2303_PRODUCT_ID_GE		0x23e3
+#define PL2303_PRODUCT_ID_GS		0x23f3
 #define PL2303_PRODUCT_ID_RSAQ2		0x04bb
 #define PL2303_PRODUCT_ID_DCU11		0x1234
 #define PL2303_PRODUCT_ID_PHAROS	0xaaa0