Merge tag 'usb-serial-5.2-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next

Johan writes:

USB-serial updates for 5.2-rc1

Here are the USB-serial updates for 5.2-rc1, including:

 - flow-control related fixes for pl2303
 - fix for an initial-termios issue
 - fix for a couple of unthrottle() races
 - fix for f81232 interrupt-handling issues
 - improved f81232 overrun handling
 - support for higher f81232 line speeds
 - support for f81232 break control

Included are also various clean ups.

All but the last four commits have been in linux-next and with no
reported issues.

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

* tag 'usb-serial-5.2-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial: (22 commits)
  USB: serial: f81232: implement break control
  USB: serial: f81232: add high baud rate support
  USB: serial: f81232: clear overrun flag
  USB: serial: f81232: fix interrupt worker not stop
  USB: serial: io_edgeport: fix up switch fall-through comments
  USB: serial: drop unused iflag macro
  USB: serial: drop unnecessary goto
  USB: serial: clean up throttle handling
  USB: serial: fix unthrottle races
  USB: serial: spcp8x5: simplify init_termios
  USB: serial: oti6858: simplify init_termios
  USB: serial: iuu_phoenix: simplify init_termios
  USB: serial: iuu_phoenix: drop bogus initial cflag
  USB: serial: cypress_m8: clean up initial-termios handling
  USB: serial: cypress_m8: drop unused termios
  USB: serial: cypress_m8: drop unused driver data flag
  USB: serial: ark3116: drop redundant init_termios
  USB: serial: fix initial-termios handling
  USB: serial: digi_acceleport: clean up set_termios
  USB: serial: digi_acceleport: clean up modem-control handling
  ...

11 files changed, 323 insertions, 172 deletions

diff --git a/drivers/usb/serial/ark3116.c b/drivers/usb/serial/ark3116.c
index ff38aa8963cf..71a9206ea1e2 100644
--- a/drivers/usb/serial/ark3116.c
+++ b/drivers/usb/serial/ark3116.c
@@ -189,16 +189,6 @@ static int ark3116_port_remove(struct usb_serial_port *port)
 	return 0;
 }
 
-static void ark3116_init_termios(struct tty_struct *tty)
-{
-	struct ktermios *termios = &tty->termios;
-	*termios = tty_std_termios;
-	termios->c_cflag = B9600 | CS8
-				      | CREAD | HUPCL | CLOCAL;
-	termios->c_ispeed = 9600;
-	termios->c_ospeed = 9600;
-}
-
 static void ark3116_set_termios(struct tty_struct *tty,
 				struct usb_serial_port *port,
 				struct ktermios *old_termios)
@@ -645,7 +635,6 @@ static struct usb_serial_driver ark3116_device = {
 	.port_probe =		ark3116_port_probe,
 	.port_remove =		ark3116_port_remove,
 	.set_termios =		ark3116_set_termios,
-	.init_termios =		ark3116_init_termios,
 	.get_serial =		ark3116_get_serial_info,
 	.tiocmget =		ark3116_tiocmget,
 	.tiocmset =		ark3116_tiocmset,
diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c
index ed51bc48eea6..72d3ae1ebc64 100644
--- a/drivers/usb/serial/cypress_m8.c
+++ b/drivers/usb/serial/cypress_m8.c
@@ -98,7 +98,6 @@ struct cypress_private {
 	int write_urb_interval;            /* interval to use for write urb */
 	int read_urb_interval;             /* interval to use for read urb */
 	int comm_is_ok;                    /* true if communication is (still) ok */
-	int termios_initialized;
 	__u8 line_control;	   	   /* holds dtr / rts value */
 	__u8 current_status;	   	   /* received from last read - info on dsr,cts,cd,ri,etc */
 	__u8 current_config;	   	   /* stores the current configuration byte */
@@ -107,11 +106,7 @@ struct cypress_private {
 	int get_cfg_unsafe;		   /* If true, the CYPRESS_GET_CONFIG is unsafe */
 	int baud_rate;			   /* stores current baud rate in
 					      integer form */
-	int isthrottled;		   /* if throttled, discard reads */
 	char prev_status;		   /* used for TIOCMIWAIT */
-	/* we pass a pointer to this as the argument sent to
-	   cypress_set_termios old_termios */
-	struct ktermios tmp_termios; 	   /* stores the old termios settings */
 };
 
 /* function prototypes for the Cypress USB to serial device */
@@ -126,6 +121,7 @@ static int  cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 			const unsigned char *buf, int count);
 static void cypress_send(struct usb_serial_port *port);
 static int  cypress_write_room(struct tty_struct *tty);
+static void cypress_earthmate_init_termios(struct tty_struct *tty);
 static void cypress_set_termios(struct tty_struct *tty,
 			struct usb_serial_port *port, struct ktermios *old);
 static int  cypress_tiocmget(struct tty_struct *tty);
@@ -153,6 +149,7 @@ static struct usb_serial_driver cypress_earthmate_device = {
 	.dtr_rts =			cypress_dtr_rts,
 	.write =			cypress_write,
 	.write_room =			cypress_write_room,
+	.init_termios =			cypress_earthmate_init_termios,
 	.set_termios =			cypress_set_termios,
 	.tiocmget =			cypress_tiocmget,
 	.tiocmset =			cypress_tiocmset,
@@ -467,7 +464,6 @@ static int cypress_generic_port_probe(struct usb_serial_port *port)
 
 	priv->cmd_ctrl = 0;
 	priv->line_control = 0;
-	priv->termios_initialized = 0;
 	priv->rx_flags = 0;
 	/* Default packet format setting is determined by packet size.
 	   Anything with a size larger then 9 must have a separate
@@ -604,7 +600,7 @@ static int cypress_open(struct tty_struct *tty, struct usb_serial_port *port)
 	cypress_send(port);
 
 	if (tty)
-		cypress_set_termios(tty, port, &priv->tmp_termios);
+		cypress_set_termios(tty, port, NULL);
 
 	/* setup the port and start reading from the device */
 	usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
@@ -857,6 +853,11 @@ static int cypress_tiocmset(struct tty_struct *tty,
 	return cypress_write(tty, port, NULL, 0);
 }
 
+static void cypress_earthmate_init_termios(struct tty_struct *tty)
+{
+	tty_encode_baud_rate(tty, 4800, 4800);
+}
+
 static void cypress_set_termios(struct tty_struct *tty,
 	struct usb_serial_port *port, struct ktermios *old_termios)
 {
@@ -868,45 +869,11 @@ static void cypress_set_termios(struct tty_struct *tty,
 	__u8 oldlines;
 	int linechange = 0;
 
-	spin_lock_irqsave(&priv->lock, flags);
-	/* We can't clean this one up as we don't know the device type
-	   early enough */
-	if (!priv->termios_initialized) {
-		if (priv->chiptype == CT_EARTHMATE) {
-			tty->termios = tty_std_termios;
-			tty->termios.c_cflag = B4800 | CS8 | CREAD | HUPCL |
-				CLOCAL;
-			tty->termios.c_ispeed = 4800;
-			tty->termios.c_ospeed = 4800;
-		} else if (priv->chiptype == CT_CYPHIDCOM) {
-			tty->termios = tty_std_termios;
-			tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
-				CLOCAL;
-			tty->termios.c_ispeed = 9600;
-			tty->termios.c_ospeed = 9600;
-		} else if (priv->chiptype == CT_CA42V2) {
-			tty->termios = tty_std_termios;
-			tty->termios.c_cflag = B9600 | CS8 | CREAD | HUPCL |
-				CLOCAL;
-			tty->termios.c_ispeed = 9600;
-			tty->termios.c_ospeed = 9600;
-		}
-		priv->termios_initialized = 1;
-	}
-	spin_unlock_irqrestore(&priv->lock, flags);
-
 	/* Unsupported features need clearing */
 	tty->termios.c_cflag &= ~(CMSPAR|CRTSCTS);
 
 	cflag = tty->termios.c_cflag;
 
-	/* check if there are new settings */
-	if (old_termios) {
-		spin_lock_irqsave(&priv->lock, flags);
-		priv->tmp_termios = tty->termios;
-		spin_unlock_irqrestore(&priv->lock, flags);
-	}
-
 	/* set number of data bits, parity, stop bits */
 	/* when parity is disabled the parity type bit is ignored */
 
diff --git a/drivers/usb/serial/digi_acceleport.c b/drivers/usb/serial/digi_acceleport.c
index e7f244cf2c07..578ebdd86520 100644
--- a/drivers/usb/serial/digi_acceleport.c
+++ b/drivers/usb/serial/digi_acceleport.c
@@ -569,9 +569,9 @@ static int digi_set_modem_signals(struct usb_serial_port *port,
 	ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
 	if (ret == 0) {
 		oob_priv->dp_write_urb_in_use = 1;
-		port_priv->dp_modem_signals =
-			(port_priv->dp_modem_signals&~(TIOCM_DTR|TIOCM_RTS))
-			| (modem_signals&(TIOCM_DTR|TIOCM_RTS));
+		port_priv->dp_modem_signals &= ~(TIOCM_DTR | TIOCM_RTS);
+		port_priv->dp_modem_signals |=
+				modem_signals & (TIOCM_DTR | TIOCM_RTS);
 	}
 	spin_unlock(&port_priv->dp_port_lock);
 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
@@ -740,9 +740,9 @@ static void digi_set_termios(struct tty_struct *tty,
 	/* set parity */
 	tty->termios.c_cflag &= ~CMSPAR;
 
-	if ((cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD))) {
-		if (cflag&PARENB) {
-			if (cflag&PARODD)
+	if ((cflag & (PARENB | PARODD)) != (old_cflag & (PARENB | PARODD))) {
+		if (cflag & PARENB) {
+			if (cflag & PARODD)
 				arg = DIGI_PARITY_ODD;
 			else
 				arg = DIGI_PARITY_EVEN;
@@ -755,9 +755,9 @@ static void digi_set_termios(struct tty_struct *tty,
 		buf[i++] = 0;
 	}
 	/* set word size */
-	if ((cflag&CSIZE) != (old_cflag&CSIZE)) {
+	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
 		arg = -1;
-		switch (cflag&CSIZE) {
+		switch (cflag & CSIZE) {
 		case CS5: arg = DIGI_WORD_SIZE_5; break;
 		case CS6: arg = DIGI_WORD_SIZE_6; break;
 		case CS7: arg = DIGI_WORD_SIZE_7; break;
@@ -765,7 +765,7 @@ static void digi_set_termios(struct tty_struct *tty,
 		default:
 			dev_dbg(dev,
 				"digi_set_termios: can't handle word size %d\n",
-				(cflag&CSIZE));
+				cflag & CSIZE);
 			break;
 		}
 
@@ -779,9 +779,9 @@ static void digi_set_termios(struct tty_struct *tty,
 	}
 
 	/* set stop bits */
-	if ((cflag&CSTOPB) != (old_cflag&CSTOPB)) {
+	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
 
-		if ((cflag&CSTOPB))
+		if ((cflag & CSTOPB))
 			arg = DIGI_STOP_BITS_2;
 		else
 			arg = DIGI_STOP_BITS_1;
@@ -794,15 +794,15 @@ static void digi_set_termios(struct tty_struct *tty,
 	}
 
 	/* set input flow control */
-	if ((iflag&IXOFF) != (old_iflag&IXOFF)
-	    || (cflag&CRTSCTS) != (old_cflag&CRTSCTS)) {
+	if ((iflag & IXOFF) != (old_iflag & IXOFF) ||
+			(cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
 		arg = 0;
-		if (iflag&IXOFF)
+		if (iflag & IXOFF)
 			arg |= DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
 		else
 			arg &= ~DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
 
-		if (cflag&CRTSCTS) {
+		if (cflag & CRTSCTS) {
 			arg |= DIGI_INPUT_FLOW_CONTROL_RTS;
 
 			/* On USB-4 it is necessary to assert RTS prior */
@@ -822,19 +822,18 @@ static void digi_set_termios(struct tty_struct *tty,
 	}
 
 	/* set output flow control */
-	if ((iflag & IXON) != (old_iflag & IXON)
-	    || (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
+	if ((iflag & IXON) != (old_iflag & IXON) ||
+			(cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
 		arg = 0;
 		if (iflag & IXON)
 			arg |= DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
 		else
 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
 
-		if (cflag & CRTSCTS) {
+		if (cflag & CRTSCTS)
 			arg |= DIGI_OUTPUT_FLOW_CONTROL_CTS;
-		} else {
+		else
 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_CTS;
-		}
 
 		buf[i++] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
 		buf[i++] = priv->dp_port_num;
@@ -1084,7 +1083,7 @@ static int digi_chars_in_buffer(struct tty_struct *tty)
 static void digi_dtr_rts(struct usb_serial_port *port, int on)
 {
 	/* Adjust DTR and RTS */
-	digi_set_modem_signals(port, on * (TIOCM_DTR|TIOCM_RTS), 1);
+	digi_set_modem_signals(port, on * (TIOCM_DTR | TIOCM_RTS), 1);
 }
 
 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c
index 0dcdcb4b2cde..43fa1f0716b7 100644
--- a/drivers/usb/serial/f81232.c
+++ b/drivers/usb/serial/f81232.c
@@ -28,7 +28,8 @@ static const struct usb_device_id id_table[] = {
 MODULE_DEVICE_TABLE(usb, id_table);
 
 /* Maximum baudrate for F81232 */
-#define F81232_MAX_BAUDRATE		115200
+#define F81232_MAX_BAUDRATE		1500000
+#define F81232_DEF_BAUDRATE		9600
 
 /* USB Control EP parameter */
 #define F81232_REGISTER_REQUEST		0xa0
@@ -41,19 +42,46 @@ MODULE_DEVICE_TABLE(usb, id_table);
 #define FIFO_CONTROL_REGISTER		(0x02 + SERIAL_BASE_ADDRESS)
 #define LINE_CONTROL_REGISTER		(0x03 + SERIAL_BASE_ADDRESS)
 #define MODEM_CONTROL_REGISTER		(0x04 + SERIAL_BASE_ADDRESS)
+#define LINE_STATUS_REGISTER		(0x05 + SERIAL_BASE_ADDRESS)
 #define MODEM_STATUS_REGISTER		(0x06 + SERIAL_BASE_ADDRESS)
 
+/*
+ * F81232 Clock registers (106h)
+ *
+ * Bit1-0:	Clock source selector
+ *			00: 1.846MHz.
+ *			01: 18.46MHz.
+ *			10: 24MHz.
+ *			11: 14.77MHz.
+ */
+#define F81232_CLK_REGISTER		0x106
+#define F81232_CLK_1_846_MHZ		0
+#define F81232_CLK_18_46_MHZ		BIT(0)
+#define F81232_CLK_24_MHZ		BIT(1)
+#define F81232_CLK_14_77_MHZ		(BIT(1) | BIT(0))
+#define F81232_CLK_MASK			GENMASK(1, 0)
+
 struct f81232_private {
 	struct mutex lock;
 	u8 modem_control;
 	u8 modem_status;
+	u8 shadow_lcr;
+	speed_t baud_base;
+	struct work_struct lsr_work;
 	struct work_struct interrupt_work;
 	struct usb_serial_port *port;
 };
 
-static int calc_baud_divisor(speed_t baudrate)
+static u32 const baudrate_table[] = { 115200, 921600, 1152000, 1500000 };
+static u8 const clock_table[] = { F81232_CLK_1_846_MHZ, F81232_CLK_14_77_MHZ,
+				F81232_CLK_18_46_MHZ, F81232_CLK_24_MHZ };
+
+static int calc_baud_divisor(speed_t baudrate, speed_t clockrate)
 {
-	return DIV_ROUND_CLOSEST(F81232_MAX_BAUDRATE, baudrate);
+	if (!baudrate)
+		return 0;
+
+	return DIV_ROUND_CLOSEST(clockrate, baudrate);
 }
 
 static int f81232_get_register(struct usb_serial_port *port, u16 reg, u8 *val)
@@ -127,6 +155,21 @@ static int f81232_set_register(struct usb_serial_port *port, u16 reg, u8 val)
 	return status;
 }
 
+static int f81232_set_mask_register(struct usb_serial_port *port, u16 reg,
+					u8 mask, u8 val)
+{
+	int status;
+	u8 tmp;
+
+	status = f81232_get_register(port, reg, &tmp);
+	if (status)
+		return status;
+
+	tmp = (tmp & ~mask) | (val & mask);
+
+	return f81232_set_register(port, reg, tmp);
+}
+
 static void f81232_read_msr(struct usb_serial_port *port)
 {
 	int status;
@@ -282,6 +325,7 @@ exit:
 static void f81232_process_read_urb(struct urb *urb)
 {
 	struct usb_serial_port *port = urb->context;
+	struct f81232_private *priv = usb_get_serial_port_data(port);
 	unsigned char *data = urb->transfer_buffer;
 	char tty_flag;
 	unsigned int i;
@@ -315,6 +359,7 @@ static void f81232_process_read_urb(struct urb *urb)
 
 			if (lsr & UART_LSR_OE) {
 				port->icount.overrun++;
+				schedule_work(&priv->lsr_work);
 				tty_insert_flip_char(&port->port, 0,
 						TTY_OVERRUN);
 			}
@@ -333,22 +378,72 @@ static void f81232_process_read_urb(struct urb *urb)
 
 static void f81232_break_ctl(struct tty_struct *tty, int break_state)
 {
-	/* FIXME - Stubbed out for now */
+	struct usb_serial_port *port = tty->driver_data;
+	struct f81232_private *priv = usb_get_serial_port_data(port);
+	int status;
 
-	/*
-	 * break_state = -1 to turn on break, and 0 to turn off break
-	 * see drivers/char/tty_io.c to see it used.
-	 * last_set_data_urb_value NEVER has the break bit set in it.
-	 */
+	mutex_lock(&priv->lock);
+
+	if (break_state)
+		priv->shadow_lcr |= UART_LCR_SBC;
+	else
+		priv->shadow_lcr &= ~UART_LCR_SBC;
+
+	status = f81232_set_register(port, LINE_CONTROL_REGISTER,
+					priv->shadow_lcr);
+	if (status)
+		dev_err(&port->dev, "set break failed: %d\n", status);
+
+	mutex_unlock(&priv->lock);
 }
 
-static void f81232_set_baudrate(struct usb_serial_port *port, speed_t baudrate)
+static int f81232_find_clk(speed_t baudrate)
 {
+	int idx;
+
+	for (idx = 0; idx < ARRAY_SIZE(baudrate_table); ++idx) {
+		if (baudrate <= baudrate_table[idx] &&
+				baudrate_table[idx] % baudrate == 0)
+			return idx;
+	}
+
+	return -EINVAL;
+}
+
+static void f81232_set_baudrate(struct tty_struct *tty,
+				struct usb_serial_port *port, speed_t baudrate,
+				speed_t old_baudrate)
+{
+	struct f81232_private *priv = usb_get_serial_port_data(port);
 	u8 lcr;
 	int divisor;
 	int status = 0;
+	int i;
+	int idx;
+	speed_t baud_list[] = { baudrate, old_baudrate, F81232_DEF_BAUDRATE };
+
+	for (i = 0; i < ARRAY_SIZE(baud_list); ++i) {
+		idx = f81232_find_clk(baud_list[i]);
+		if (idx >= 0) {
+			baudrate = baud_list[i];
+			tty_encode_baud_rate(tty, baudrate, baudrate);
+			break;
+		}
+	}
 
-	divisor = calc_baud_divisor(baudrate);
+	if (idx < 0)
+		return;
+
+	priv->baud_base = baudrate_table[idx];
+	divisor = calc_baud_divisor(baudrate, priv->baud_base);
+
+	status = f81232_set_mask_register(port, F81232_CLK_REGISTER,
+			F81232_CLK_MASK, clock_table[idx]);
+	if (status) {
+		dev_err(&port->dev, "%s failed to set CLK_REG: %d\n",
+			__func__, status);
+		return;
+	}
 
 	status = f81232_get_register(port, LINE_CONTROL_REGISTER,
 			 &lcr); /* get LCR */
@@ -435,9 +530,11 @@ static int f81232_port_disable(struct usb_serial_port *port)
 static void f81232_set_termios(struct tty_struct *tty,
 		struct usb_serial_port *port, struct ktermios *old_termios)
 {
+	struct f81232_private *priv = usb_get_serial_port_data(port);
 	u8 new_lcr = 0;
 	int status = 0;
 	speed_t baudrate;
+	speed_t old_baud;
 
 	/* Don't change anything if nothing has changed */
 	if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
@@ -450,11 +547,12 @@ static void f81232_set_termios(struct tty_struct *tty,
 
 	baudrate = tty_get_baud_rate(tty);
 	if (baudrate > 0) {
-		if (baudrate > F81232_MAX_BAUDRATE) {
-			baudrate = F81232_MAX_BAUDRATE;
-			tty_encode_baud_rate(tty, baudrate, baudrate);
-		}
-		f81232_set_baudrate(port, baudrate);
+		if (old_termios)
+			old_baud = tty_termios_baud_rate(old_termios);
+		else
+			old_baud = F81232_DEF_BAUDRATE;
+
+		f81232_set_baudrate(tty, port, baudrate, old_baud);
 	}
 
 	if (C_PARENB(tty)) {
@@ -486,11 +584,18 @@ static void f81232_set_termios(struct tty_struct *tty,
 		break;
 	}
 
+	mutex_lock(&priv->lock);
+
+	new_lcr |= (priv->shadow_lcr & UART_LCR_SBC);
 	status = f81232_set_register(port, LINE_CONTROL_REGISTER, new_lcr);
 	if (status) {
 		dev_err(&port->dev, "%s failed to set LCR: %d\n",
 			__func__, status);
 	}
+
+	priv->shadow_lcr = new_lcr;
+
+	mutex_unlock(&priv->lock);
 }
 
 static int f81232_tiocmget(struct tty_struct *tty)
@@ -556,9 +661,13 @@ static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port)
 
 static void f81232_close(struct usb_serial_port *port)
 {
+	struct f81232_private *port_priv = usb_get_serial_port_data(port);
+
 	f81232_port_disable(port);
 	usb_serial_generic_close(port);
 	usb_kill_urb(port->interrupt_in_urb);
+	flush_work(&port_priv->interrupt_work);
+	flush_work(&port_priv->lsr_work);
 }
 
 static void f81232_dtr_rts(struct usb_serial_port *port, int on)
@@ -587,11 +696,12 @@ static int f81232_get_serial_info(struct tty_struct *tty,
 		struct serial_struct *ss)
 {
 	struct usb_serial_port *port = tty->driver_data;
+	struct f81232_private *priv = usb_get_serial_port_data(port);
 
 	ss->type = PORT_16550A;
 	ss->line = port->minor;
 	ss->port = port->port_number;
-	ss->baud_base = F81232_MAX_BAUDRATE;
+	ss->baud_base = priv->baud_base;
 	return 0;
 }
 
@@ -603,6 +713,21 @@ static void  f81232_interrupt_work(struct work_struct *work)
 	f81232_read_msr(priv->port);
 }
 
+static void f81232_lsr_worker(struct work_struct *work)
+{
+	struct f81232_private *priv;
+	struct usb_serial_port *port;
+	int status;
+	u8 tmp;
+
+	priv = container_of(work, struct f81232_private, lsr_work);
+	port = priv->port;
+
+	status = f81232_get_register(port, LINE_STATUS_REGISTER, &tmp);
+	if (status)
+		dev_warn(&port->dev, "read LSR failed: %d\n", status);
+}
+
 static int f81232_port_probe(struct usb_serial_port *port)
 {
 	struct f81232_private *priv;
@@ -613,6 +738,7 @@ static int f81232_port_probe(struct usb_serial_port *port)
 
 	mutex_init(&priv->lock);
 	INIT_WORK(&priv->interrupt_work,  f81232_interrupt_work);
+	INIT_WORK(&priv->lsr_work, f81232_lsr_worker);
 
 	usb_set_serial_port_data(port, priv);
 
@@ -632,6 +758,42 @@ static int f81232_port_remove(struct usb_serial_port *port)
 	return 0;
 }
 
+static int f81232_suspend(struct usb_serial *serial, pm_message_t message)
+{
+	struct usb_serial_port *port = serial->port[0];
+	struct f81232_private *port_priv = usb_get_serial_port_data(port);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
+		usb_kill_urb(port->read_urbs[i]);
+
+	usb_kill_urb(port->interrupt_in_urb);
+
+	if (port_priv) {
+		flush_work(&port_priv->interrupt_work);
+		flush_work(&port_priv->lsr_work);
+	}
+
+	return 0;
+}
+
+static int f81232_resume(struct usb_serial *serial)
+{
+	struct usb_serial_port *port = serial->port[0];
+	int result;
+
+	if (tty_port_initialized(&port->port)) {
+		result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
+		if (result) {
+			dev_err(&port->dev, "submit interrupt urb failed: %d\n",
+					result);
+			return result;
+		}
+	}
+
+	return usb_serial_generic_resume(serial);
+}
+
 static struct usb_serial_driver f81232_device = {
 	.driver = {
 		.owner =	THIS_MODULE,
@@ -655,6 +817,8 @@ static struct usb_serial_driver f81232_device = {
 	.read_int_callback =	f81232_read_int_callback,
 	.port_probe =		f81232_port_probe,
 	.port_remove =		f81232_port_remove,
+	.suspend =		f81232_suspend,
+	.resume =		f81232_resume,
 };
 
 static struct usb_serial_driver * const serial_drivers[] = {
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c
index 2274d9625f63..1be8bea372a2 100644
--- a/drivers/usb/serial/generic.c
+++ b/drivers/usb/serial/generic.c
@@ -106,12 +106,8 @@ void usb_serial_generic_deregister(void)
 int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
 	int result = 0;
-	unsigned long flags;
 
-	spin_lock_irqsave(&port->lock, flags);
-	port->throttled = 0;
-	port->throttle_req = 0;
-	spin_unlock_irqrestore(&port->lock, flags);
+	clear_bit(USB_SERIAL_THROTTLED, &port->flags);
 
 	if (port->bulk_in_size)
 		result = usb_serial_generic_submit_read_urbs(port, GFP_KERNEL);
@@ -375,7 +371,7 @@ void usb_serial_generic_read_bulk_callback(struct urb *urb)
 {
 	struct usb_serial_port *port = urb->context;
 	unsigned char *data = urb->transfer_buffer;
-	unsigned long flags;
+	bool stopped = false;
 	int status = urb->status;
 	int i;
 
@@ -383,42 +379,55 @@ void usb_serial_generic_read_bulk_callback(struct urb *urb)
 		if (urb == port->read_urbs[i])
 			break;
 	}
-	set_bit(i, &port->read_urbs_free);
 
 	dev_dbg(&port->dev, "%s - urb %d, len %d\n", __func__, i,
 							urb->actual_length);
 	switch (status) {
 	case 0:
+		usb_serial_debug_data(&port->dev, __func__, urb->actual_length,
+							data);
+		port->serial->type->process_read_urb(urb);
 		break;
 	case -ENOENT:
 	case -ECONNRESET:
 	case -ESHUTDOWN:
 		dev_dbg(&port->dev, "%s - urb stopped: %d\n",
 							__func__, status);
-		return;
+		stopped = true;
+		break;
 	case -EPIPE:
 		dev_err(&port->dev, "%s - urb stopped: %d\n",
 							__func__, status);
-		return;
+		stopped = true;
+		break;
 	default:
 		dev_dbg(&port->dev, "%s - nonzero urb status: %d\n",
 							__func__, status);
-		goto resubmit;
+		break;
 	}
 
-	usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
-	port->serial->type->process_read_urb(urb);
+	/*
+	 * Make sure URB processing is done before marking as free to avoid
+	 * racing with unthrottle() on another CPU. Matches the barriers
+	 * implied by the test_and_clear_bit() in
+	 * usb_serial_generic_submit_read_urb().
+	 */
+	smp_mb__before_atomic();
+	set_bit(i, &port->read_urbs_free);
+	/*
+	 * Make sure URB is marked as free before checking the throttled flag
+	 * to avoid racing with unthrottle() on another CPU. Matches the
+	 * smp_mb() in unthrottle().
+	 */
+	smp_mb__after_atomic();
 
-resubmit:
-	/* Throttle the device if requested by tty */
-	spin_lock_irqsave(&port->lock, flags);
-	port->throttled = port->throttle_req;
-	if (!port->throttled) {
-		spin_unlock_irqrestore(&port->lock, flags);
-		usb_serial_generic_submit_read_urb(port, i, GFP_ATOMIC);
-	} else {
-		spin_unlock_irqrestore(&port->lock, flags);
-	}
+	if (stopped)
+		return;
+
+	if (test_bit(USB_SERIAL_THROTTLED, &port->flags))
+		return;
+
+	usb_serial_generic_submit_read_urb(port, i, GFP_ATOMIC);
 }
 EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback);
 
@@ -454,10 +463,9 @@ void usb_serial_generic_write_bulk_callback(struct urb *urb)
 	default:
 		dev_err_console(port, "%s - nonzero urb status: %d\n",
 							__func__, status);
-		goto resubmit;
+		break;
 	}
 
-resubmit:
 	usb_serial_generic_write_start(port, GFP_ATOMIC);
 	usb_serial_port_softint(port);
 }
@@ -466,26 +474,24 @@ EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
 void usb_serial_generic_throttle(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
-	unsigned long flags;
 
-	spin_lock_irqsave(&port->lock, flags);
-	port->throttle_req = 1;
-	spin_unlock_irqrestore(&port->lock, flags);
+	set_bit(USB_SERIAL_THROTTLED, &port->flags);
 }
 EXPORT_SYMBOL_GPL(usb_serial_generic_throttle);
 
 void usb_serial_generic_unthrottle(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
-	int was_throttled;
 
-	spin_lock_irq(&port->lock);
-	was_throttled = port->throttled;
-	port->throttled = port->throttle_req = 0;
-	spin_unlock_irq(&port->lock);
+	clear_bit(USB_SERIAL_THROTTLED, &port->flags);
+
+	/*
+	 * Matches the smp_mb__after_atomic() in
+	 * usb_serial_generic_read_bulk_callback().
+	 */
+	smp_mb();
 
-	if (was_throttled)
-		usb_serial_generic_submit_read_urbs(port, GFP_KERNEL);
+	usb_serial_generic_submit_read_urbs(port, GFP_KERNEL);
 }
 EXPORT_SYMBOL_GPL(usb_serial_generic_unthrottle);
 
diff --git a/drivers/usb/serial/io_edgeport.c b/drivers/usb/serial/io_edgeport.c
index 4ca31c0e4174..48a439298a68 100644
--- a/drivers/usb/serial/io_edgeport.c
+++ b/drivers/usb/serial/io_edgeport.c
@@ -1751,7 +1751,7 @@ static void process_rcvd_data(struct edgeport_serial *edge_serial,
 				edge_serial->rxState = EXPECT_HDR2;
 				break;
 			}
-			/* otherwise, drop on through */
+			/* Fall through */
 		case EXPECT_HDR2:
 			edge_serial->rxHeader2 = *buffer;
 			++buffer;
@@ -1790,29 +1790,20 @@ static void process_rcvd_data(struct edgeport_serial *edge_serial,
 						edge_serial->rxHeader2, 0);
 				edge_serial->rxState = EXPECT_HDR1;
 				break;
-			} else {
-				edge_serial->rxPort =
-				    IOSP_GET_HDR_PORT(edge_serial->rxHeader1);
-				edge_serial->rxBytesRemaining =
-				    IOSP_GET_HDR_DATA_LEN(
-						edge_serial->rxHeader1,
-						edge_serial->rxHeader2);
-				dev_dbg(dev, "%s - Data for Port %u Len %u\n",
-					__func__,
-					edge_serial->rxPort,
-					edge_serial->rxBytesRemaining);
-
-				/* ASSERT(DevExt->RxPort < DevExt->NumPorts);
-				 * ASSERT(DevExt->RxBytesRemaining <
-				 *		IOSP_MAX_DATA_LENGTH);
-				 */
-
-				if (bufferLength == 0) {
-					edge_serial->rxState = EXPECT_DATA;
-					break;
-				}
-				/* Else, drop through */
 			}
+
+			edge_serial->rxPort = IOSP_GET_HDR_PORT(edge_serial->rxHeader1);
+			edge_serial->rxBytesRemaining = IOSP_GET_HDR_DATA_LEN(edge_serial->rxHeader1,
+									      edge_serial->rxHeader2);
+			dev_dbg(dev, "%s - Data for Port %u Len %u\n", __func__,
+				edge_serial->rxPort,
+				edge_serial->rxBytesRemaining);
+
+			if (bufferLength == 0) {
+				edge_serial->rxState = EXPECT_DATA;
+				break;
+			}
+			/* Fall through */
 		case EXPECT_DATA: /* Expect data */
 			if (bufferLength < edge_serial->rxBytesRemaining) {
 				rxLen = bufferLength;
diff --git a/drivers/usb/serial/iuu_phoenix.c b/drivers/usb/serial/iuu_phoenix.c
index 449e89db9cea..d5bff69b1769 100644
--- a/drivers/usb/serial/iuu_phoenix.c
+++ b/drivers/usb/serial/iuu_phoenix.c
@@ -942,9 +942,7 @@ static void iuu_close(struct usb_serial_port *port)
 
 static void iuu_init_termios(struct tty_struct *tty)
 {
-	tty->termios = tty_std_termios;
-	tty->termios.c_cflag = CLOCAL | CREAD | CS8 | B9600
-				| TIOCM_CTS | CSTOPB | PARENB;
+	tty->termios.c_cflag = B9600 | CS8 | CSTOPB | CREAD | PARENB | CLOCAL;
 	tty->termios.c_ispeed = 9600;
 	tty->termios.c_ospeed = 9600;
 	tty->termios.c_lflag = 0;
diff --git a/drivers/usb/serial/oti6858.c b/drivers/usb/serial/oti6858.c
index ae9cb15ee02d..38ae0fc826cc 100644
--- a/drivers/usb/serial/oti6858.c
+++ b/drivers/usb/serial/oti6858.c
@@ -393,10 +393,7 @@ static int oti6858_chars_in_buffer(struct tty_struct *tty)
 
 static void oti6858_init_termios(struct tty_struct *tty)
 {
-	tty->termios = tty_std_termios;
-	tty->termios.c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
-	tty->termios.c_ispeed = 38400;
-	tty->termios.c_ospeed = 38400;
+	tty_encode_baud_rate(tty, 38400, 38400);
 }
 
 static void oti6858_set_termios(struct tty_struct *tty,
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index bb3f9aa4a909..55122ac84518 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -145,6 +145,8 @@ MODULE_DEVICE_TABLE(usb, id_table);
 #define UART_OVERRUN_ERROR		0x40
 #define UART_CTS			0x80
 
+#define PL2303_FLOWCTRL_MASK		0xf0
+
 static void pl2303_set_break(struct usb_serial_port *port, bool enable);
 
 enum pl2303_type {
@@ -156,6 +158,7 @@ enum pl2303_type {
 struct pl2303_type_data {
 	speed_t max_baud_rate;
 	unsigned long quirks;
+	unsigned int no_autoxonxoff:1;
 };
 
 struct pl2303_serial_private {
@@ -173,11 +176,12 @@ struct pl2303_private {
 
 static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
 	[TYPE_01] = {
-		.max_baud_rate =	1228800,
-		.quirks =		PL2303_QUIRK_LEGACY,
+		.max_baud_rate		= 1228800,
+		.quirks			= PL2303_QUIRK_LEGACY,
+		.no_autoxonxoff		= true,
 	},
 	[TYPE_HX] = {
-		.max_baud_rate =	12000000,
+		.max_baud_rate		= 12000000,
 	},
 };
 
@@ -223,6 +227,29 @@ static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
 	return 0;
 }
 
+static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val)
+{
+	int ret = 0;
+	u8 *buf;
+
+	buf = kmalloc(1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = pl2303_vendor_read(serial, reg | 0x80, buf);
+	if (ret)
+		goto out_free;
+
+	*buf &= ~mask;
+	*buf |= val & mask;
+
+	ret = pl2303_vendor_write(serial, reg, *buf);
+out_free:
+	kfree(buf);
+
+	return ret;
+}
+
 static int pl2303_probe(struct usb_serial *serial,
 					const struct usb_device_id *id)
 {
@@ -552,6 +579,20 @@ static bool pl2303_termios_change(const struct ktermios *a, const struct ktermio
 	return tty_termios_hw_change(a, b) || ixon_change;
 }
 
+static bool pl2303_enable_xonxoff(struct tty_struct *tty, const struct pl2303_type_data *type)
+{
+	if (!I_IXON(tty) || I_IXANY(tty))
+		return false;
+
+	if (START_CHAR(tty) != 0x11 || STOP_CHAR(tty) != 0x13)
+		return false;
+
+	if (type->no_autoxonxoff)
+		return false;
+
+	return true;
+}
+
 static void pl2303_set_termios(struct tty_struct *tty,
 		struct usb_serial_port *port, struct ktermios *old_termios)
 {
@@ -678,14 +719,13 @@ static void pl2303_set_termios(struct tty_struct *tty,
 
 	if (C_CRTSCTS(tty)) {
 		if (spriv->quirks & PL2303_QUIRK_LEGACY)
-			pl2303_vendor_write(serial, 0x0, 0x41);
+			pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40);
 		else
-			pl2303_vendor_write(serial, 0x0, 0x61);
-	} else if (I_IXON(tty) && !I_IXANY(tty) && START_CHAR(tty) == 0x11 &&
-			STOP_CHAR(tty) == 0x13) {
-		pl2303_vendor_write(serial, 0x0, 0xc0);
+			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);
 	} else {
-		pl2303_vendor_write(serial, 0x0, 0x0);
+		pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0);
 	}
 
 	kfree(buf);
diff --git a/drivers/usb/serial/spcp8x5.c b/drivers/usb/serial/spcp8x5.c
index b42714855364..3bac55bd9bd9 100644
--- a/drivers/usb/serial/spcp8x5.c
+++ b/drivers/usb/serial/spcp8x5.c
@@ -281,10 +281,7 @@ static void spcp8x5_dtr_rts(struct usb_serial_port *port, int on)
 
 static void spcp8x5_init_termios(struct tty_struct *tty)
 {
-	tty->termios = tty_std_termios;
-	tty->termios.c_cflag = B115200 | CS8 | CREAD | HUPCL | CLOCAL;
-	tty->termios.c_ispeed = 115200;
-	tty->termios.c_ospeed = 115200;
+	tty_encode_baud_rate(tty, 115200, 115200);
 }
 
 static void spcp8x5_set_termios(struct tty_struct *tty,
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 7e89efbf2c28..676c296103a2 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -164,9 +164,9 @@ void usb_serial_put(struct usb_serial *serial)
  * @driver: the driver (USB in our case)
  * @tty: the tty being created
  *
- * Create the termios objects for this tty.  We use the default
+ * Initialise the termios structure for this tty.  We use the default
  * USB serial settings but permit them to be overridden by
- * serial->type->init_termios.
+ * serial->type->init_termios on first open.
  *
  * This is the first place a new tty gets used.  Hence this is where we
  * acquire references to the usb_serial structure and the driver module,
@@ -178,6 +178,7 @@ static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
 	int idx = tty->index;
 	struct usb_serial *serial;
 	struct usb_serial_port *port;
+	bool init_termios;
 	int retval = -ENODEV;
 
 	port = usb_serial_port_get_by_minor(idx);
@@ -192,14 +193,16 @@ static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
 	if (retval)
 		goto error_get_interface;
 
+	init_termios = (driver->termios[idx] == NULL);
+
 	retval = tty_standard_install(driver, tty);
 	if (retval)
 		goto error_init_termios;
 
 	mutex_unlock(&serial->disc_mutex);
 
-	/* allow the driver to update the settings */
-	if (serial->type->init_termios)
+	/* allow the driver to update the initial settings */
+	if (init_termios && serial->type->init_termios)
 		serial->type->init_termios(tty);
 
 	tty->driver_data = port;