1 files changed, 304 insertions, 355 deletions

diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index e7a84f0f517..b3d5a35c0d4 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -4,11 +4,6 @@
  * Copyright (C) 2001-2007 Greg Kroah-Hartman (greg@kroah.com)
  * Copyright (C) 2003 IBM Corp.
  *
- * Copyright (C) 2009, 2013 Frank Schäfer <fschaefer.oss@googlemail.com>
- *  - fixes, improvements and documentation for the baud rate encoding methods
- * Copyright (C) 2013 Reinhard Max <max@suse.de>
- *  - fixes and improvements for the divisor based baud rate encoding method
- *
  * Original driver for 2.2.x by anonymous
  *
  *	This program is free software; you can redistribute it and/or
@@ -17,12 +12,10 @@
  *
  * See Documentation/usb/usb-serial.txt for more information on using this
  * driver
- *
  */
 
 #include <linux/kernel.h>
 #include <linux/errno.h>
-#include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/tty.h>
 #include <linux/tty_driver.h>
@@ -37,10 +30,9 @@
 #include <asm/unaligned.h>
 #include "pl2303.h"
 
-/*
- * Version Information
- */
-#define DRIVER_DESC "Prolific PL2303 USB to serial adaptor driver"
+
+#define PL2303_QUIRK_UART_STATE_IDX0		BIT(0)
+#define PL2303_QUIRK_LEGACY			BIT(1)
 
 static const struct usb_device_id id_table[] = {
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },
@@ -69,9 +61,12 @@ static const struct usb_device_id id_table[] = {
 	{ USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
 	{ USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
 	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_PRODUCT_ID) },
-	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1) },
-	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65) },
-	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75) },
+	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1),
+		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
+	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65),
+		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
+	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75),
+		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81) },
 	{ USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
 	{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
@@ -88,6 +83,9 @@ static const struct usb_device_id id_table[] = {
 	{ USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
 	{ USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
+	{ USB_DEVICE(HP_VENDOR_ID, HP_LD960_PRODUCT_ID) },
+	{ USB_DEVICE(HP_VENDOR_ID, HP_LCM220_PRODUCT_ID) },
+	{ USB_DEVICE(HP_VENDOR_ID, HP_LCM960_PRODUCT_ID) },
 	{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
 	{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
 	{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
@@ -121,7 +119,8 @@ MODULE_DEVICE_TABLE(usb, id_table);
 #define VENDOR_READ_REQUEST_TYPE	0xc0
 #define VENDOR_READ_REQUEST		0x01
 
-#define UART_STATE			0x08
+#define UART_STATE_INDEX		8
+#define UART_STATE_MSR_MASK		0x8b
 #define UART_STATE_TRANSIENT_MASK	0x74
 #define UART_DCD			0x01
 #define UART_DSR			0x02
@@ -134,129 +133,142 @@ MODULE_DEVICE_TABLE(usb, id_table);
 
 
 enum pl2303_type {
-	type_0,		/* H version ? */
-	type_1,		/* H version ? */
-	HX_TA,		/* HX(A) / X(A) / TA version  */ /* TODO: improve */
-	HXD_EA_RA_SA,	/* HXD / EA / RA / SA version */ /* TODO: improve */
-	TB,		/* TB version */
+	TYPE_01,	/* Type 0 and 1 (difference unknown) */
+	TYPE_HX,	/* HX version of the pl2303 chip */
+	TYPE_COUNT
+};
+
+struct pl2303_type_data {
+	speed_t max_baud_rate;
+	unsigned long quirks;
 };
-/*
- * NOTE: don't know the difference between type 0 and type 1,
- * until someone from Prolific tells us...
- * TODO: distinguish between X/HX, TA and HXD, EA, RA, SA variants
- */
 
 struct pl2303_serial_private {
-	enum pl2303_type type;
+	const struct pl2303_type_data *type;
+	unsigned long quirks;
 };
 
 struct pl2303_private {
 	spinlock_t lock;
 	u8 line_control;
 	u8 line_status;
+
+	u8 line_settings[7];
 };
 
-static int pl2303_vendor_read(__u16 value, __u16 index,
-		struct usb_serial *serial, unsigned char *buf)
+static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
+	[TYPE_01] = {
+		.max_baud_rate =	1228800,
+		.quirks =		PL2303_QUIRK_LEGACY,
+	},
+};
+
+static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
+							unsigned char buf[1])
 {
-	int res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
+	struct device *dev = &serial->interface->dev;
+	int res;
+
+	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 			VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
-			value, index, buf, 1, 100);
-	dev_dbg(&serial->interface->dev, "0x%x:0x%x:0x%x:0x%x  %d - %x\n",
-		VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, value, index,
-		res, buf[0]);
-	return res;
+			value, 0, buf, 1, 100);
+	if (res != 1) {
+		dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
+								value, res);
+		if (res >= 0)
+			res = -EIO;
+
+		return res;
+	}
+
+	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
+
+	return 0;
 }
 
-static int pl2303_vendor_write(__u16 value, __u16 index,
-		struct usb_serial *serial)
+static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
 {
-	int res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+	struct device *dev = &serial->interface->dev;
+	int res;
+
+	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
+
+	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 			VENDOR_WRITE_REQUEST, VENDOR_WRITE_REQUEST_TYPE,
 			value, index, NULL, 0, 100);
-	dev_dbg(&serial->interface->dev, "0x%x:0x%x:0x%x:0x%x  %d\n",
-		VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, value, index,
-		res);
-	return res;
+	if (res) {
+		dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
+								value, res);
+		return res;
+	}
+
+	return 0;
+}
+
+static int pl2303_probe(struct usb_serial *serial,
+					const struct usb_device_id *id)
+{
+	usb_set_serial_data(serial, (void *)id->driver_info);
+
+	return 0;
 }
 
 static int pl2303_startup(struct usb_serial *serial)
 {
 	struct pl2303_serial_private *spriv;
-	enum pl2303_type type = type_0;
-	char *type_str = "unknown (treating as type_0)";
+	enum pl2303_type type = TYPE_01;
 	unsigned char *buf;
 
 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
 	if (!spriv)
 		return -ENOMEM;
 
-	buf = kmalloc(10, GFP_KERNEL);
+	buf = kmalloc(1, GFP_KERNEL);
 	if (!buf) {
 		kfree(spriv);
 		return -ENOMEM;
 	}
 
-	if (serial->dev->descriptor.bDeviceClass == 0x02) {
-		type = type_0;
-		type_str = "type_0";
-	} else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40) {
-		/*
-		 * NOTE: The bcdDevice version is the only difference between
-		 * the device descriptors of the X/HX, HXD, EA, RA, SA, TA, TB
-		 */
-		if (le16_to_cpu(serial->dev->descriptor.bcdDevice) == 0x300) {
-			type = HX_TA;
-			type_str = "X/HX/TA";
-		} else if (le16_to_cpu(serial->dev->descriptor.bcdDevice)
-								     == 0x400) {
-			type = HXD_EA_RA_SA;
-			type_str = "HXD/EA/RA/SA";
-		} else if (le16_to_cpu(serial->dev->descriptor.bcdDevice)
-								     == 0x500) {
-			type = TB;
-			type_str = "TB";
-		} else {
-			dev_info(&serial->interface->dev,
-					   "unknown/unsupported device type\n");
-			kfree(spriv);
-			kfree(buf);
-			return -ENODEV;
-		}
-	} else if (serial->dev->descriptor.bDeviceClass == 0x00
-		   || serial->dev->descriptor.bDeviceClass == 0xFF) {
-		type = type_1;
-		type_str = "type_1";
-	}
-	dev_dbg(&serial->interface->dev, "device type: %s\n", type_str);
+	if (serial->dev->descriptor.bDeviceClass == 0x02)
+		type = TYPE_01;		/* type 0 */
+	else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
+		type = TYPE_HX;
+	else if (serial->dev->descriptor.bDeviceClass == 0x00)
+		type = TYPE_01;		/* type 1 */
+	else if (serial->dev->descriptor.bDeviceClass == 0xFF)
+		type = TYPE_01;		/* type 1 */
+	dev_dbg(&serial->interface->dev, "device type: %d\n", type);
+
+	spriv->type = &pl2303_type_data[type];
+	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
+	spriv->quirks |= spriv->type->quirks;
 
-	spriv->type = type;
 	usb_set_serial_data(serial, spriv);
 
-	pl2303_vendor_read(0x8484, 0, serial, buf);
-	pl2303_vendor_write(0x0404, 0, serial);
-	pl2303_vendor_read(0x8484, 0, serial, buf);
-	pl2303_vendor_read(0x8383, 0, serial, buf);
-	pl2303_vendor_read(0x8484, 0, serial, buf);
-	pl2303_vendor_write(0x0404, 1, serial);
-	pl2303_vendor_read(0x8484, 0, serial, buf);
-	pl2303_vendor_read(0x8383, 0, serial, buf);
-	pl2303_vendor_write(0, 1, serial);
-	pl2303_vendor_write(1, 0, serial);
-	if (type == type_0 || type == type_1)
-		pl2303_vendor_write(2, 0x24, serial);
+	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(2, 0x44, serial);
+		pl2303_vendor_write(serial, 2, 0x44);
 
 	kfree(buf);
+
 	return 0;
 }
 
 static void pl2303_release(struct usb_serial *serial)
 {
-	struct pl2303_serial_private *spriv;
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 
-	spriv = usb_get_serial_data(serial);
 	kfree(spriv);
 }
 
@@ -279,9 +291,8 @@ static int pl2303_port_probe(struct usb_serial_port *port)
 
 static int pl2303_port_remove(struct usb_serial_port *port)
 {
-	struct pl2303_private *priv;
+	struct pl2303_private *priv = usb_get_serial_port_data(port);
 
-	priv = usb_get_serial_port_data(port);
 	kfree(priv);
 
 	return 0;
@@ -292,181 +303,157 @@ static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
 	struct usb_device *dev = port->serial->dev;
 	int retval;
 
+	dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
+
 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
 				 value, 0, NULL, 0, 100);
-	dev_dbg(&port->dev, "%s - value = %d, retval = %d\n", __func__,
-		value, retval);
+	if (retval)
+		dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
+
 	return retval;
 }
 
-static int pl2303_baudrate_encode_direct(int baud, enum pl2303_type type,
-								      u8 buf[4])
+/*
+ * Returns the nearest supported baud rate that can be set directly without
+ * using divisors.
+ */
+static speed_t pl2303_get_supported_baud_rate(speed_t baud)
 {
-	/*
-	 * NOTE: Only the values defined in baud_sup are supported !
-	 *       => if unsupported values are set, the PL2303 seems to
-	 *	    use 9600 baud (at least my PL2303X always does)
-	 */
-	const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400, 3600,
-				 4800, 7200, 9600, 14400, 19200, 28800, 38400,
-				 57600, 115200, 230400, 460800, 614400, 921600,
-				 1228800, 2457600, 3000000, 6000000, 12000000 };
-	/*
-	 * NOTE: With the exception of type_0/1 devices, the following
-	 * additional baud rates are supported (tested with HX rev. 3A only):
-	 * 110*, 56000*, 128000, 134400, 161280, 201600, 256000*, 268800,
-	 * 403200, 806400.	(*: not HX)
-	 *
-	 * Maximum values: HXD, TB: 12000000; HX, TA: 6000000;
-	 *                 type_0+1: 1228800; RA: 921600; SA: 115200
-	 *
-	 * As long as we are not using this encoding method for anything else
-	 * than the type_0+1 and HX chips, there is no point in complicating
-	 * the code to support them.
-	 */
-	int i;
+	static const speed_t baud_sup[] = {
+		75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
+		14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
+		614400, 921600, 1228800, 2457600, 3000000, 6000000
+	};
+
+	unsigned i;
 
-	/* Set baudrate to nearest supported value */
 	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
 		if (baud_sup[i] > baud)
 			break;
 	}
+
 	if (i == ARRAY_SIZE(baud_sup))
 		baud = baud_sup[i - 1];
 	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
 		baud = baud_sup[i - 1];
 	else
 		baud = baud_sup[i];
-	/* Respect the chip type specific baud rate limits */
-	/*
-	 * FIXME: as long as we don't know how to distinguish between the
-	 * HXD, EA, RA, and SA chip variants, allow the max. value of 12M.
-	 */
-	if (type == HX_TA)
-		baud = min_t(int, baud, 6000000);
-	else if (type == type_0 || type == type_1)
-		baud = min_t(int, baud, 1228800);
-	/* Direct (standard) baud rate encoding method */
+
+	return baud;
+}
+
+/*
+ * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
+ *       use 9600 baud.
+ */
+static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
+								speed_t baud)
+{
 	put_unaligned_le32(baud, buf);
 
 	return baud;
 }
 
-static int pl2303_baudrate_encode_divisor(int baud, enum pl2303_type type,
-								      u8 buf[4])
+static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
+								speed_t baud)
 {
-	/*
-	 * Divisor based baud rate encoding method
-	 *
-	 * NOTE: it's not clear if the type_0/1 chips support this method
-	 *
-	 * divisor = 12MHz * 32 / baudrate = 2^A * B
-	 *
-	 * with
-	 *
-	 * A = buf[1] & 0x0e
-	 * B = buf[0]  +  (buf[1] & 0x01) << 8
-	 *
-	 * Special cases:
-	 * => 8 < B < 16: device seems to work not properly
-	 * => B <= 8: device uses the max. value B = 512 instead
-	 */
-	unsigned int A, B;
+	unsigned int tmp;
 
 	/*
-	 * NOTE: The Windows driver allows maximum baud rates of 110% of the
-	 * specified maximium value.
-	 * Quick tests with early (2004) HX (rev. A) chips suggest, that even
-	 * higher baud rates (up to the maximum of 24M baud !) are working fine,
-	 * but that should really be tested carefully in "real life" scenarios
-	 * before removing the upper limit completely.
-	 * Baud rates smaller than the specified 75 baud are definitely working
-	 * fine.
+	 * Apparently the formula is:
+	 * baudrate = 12M * 32 / (2^buf[1]) / buf[0]
 	 */
-	if (type == type_0 || type == type_1)
-		baud = min_t(int, baud, 1228800 * 1.1);
-	else if (type == HX_TA)
-		baud = min_t(int, baud, 6000000 * 1.1);
-	else if (type == HXD_EA_RA_SA)
-		/* HXD, EA: 12Mbps; RA: 1Mbps; SA: 115200 bps */
-		/*
-		 * FIXME: as long as we don't know how to distinguish between
-		 * these chip variants, allow the max. of these values
-		 */
-		baud = min_t(int, baud, 12000000 * 1.1);
-	else if (type == TB)
-		baud = min_t(int, baud, 12000000 * 1.1);
-	/* Determine factors A and B */
-	A = 0;
-	B = 12000000 * 32 / baud;  /* 12MHz */
-	B <<= 1; /* Add one bit for rounding */
-	while (B > (512 << 1) && A <= 14) {
-		A += 2;
-		B >>= 2;
-	}
-	if (A > 14) { /* max. divisor = min. baudrate reached */
-		A = 14;
-		B = 512;
-		/* => ~45.78 baud */
-	} else {
-		B = (B + 1) >> 1; /* Round the last bit */
-	}
-	/* Handle special cases */
-	if (B == 512)
-		B = 0; /* also: 1 to 8 */
-	else if (B < 16)
-		/*
-		 * NOTE: With the current algorithm this happens
-		 * only for A=0 and means that the min. divisor
-		 * (respectively: the max. baudrate) is reached.
-		 */
-		B = 16;		/* => 24 MBaud */
-	/* Encode the baud rate */
-	buf[3] = 0x80;     /* Select divisor encoding method */
+	tmp = 12000000 * 32 / baud;
+	buf[3] = 0x80;
 	buf[2] = 0;
-	buf[1] = (A & 0x0e);		/* A */
-	buf[1] |= ((B & 0x100) >> 8);	/* MSB of B */
-	buf[0] = B & 0xff;		/* 8 LSBs of B */
-	/* Calculate the actual/resulting baud rate */
-	if (B <= 8)
-		B = 512;
-	baud = 12000000 * 32 / ((1 << A) * B);
+	buf[1] = (tmp >= 256);
+	while (tmp >= 256) {
+		tmp >>= 2;
+		buf[1] <<= 1;
+	}
+	buf[0] = tmp;
 
 	return baud;
 }
 
-static void pl2303_encode_baudrate(struct tty_struct *tty,
+static void pl2303_encode_baud_rate(struct tty_struct *tty,
 					struct usb_serial_port *port,
-					enum pl2303_type type,
 					u8 buf[4])
 {
-	int baud;
+	struct usb_serial *serial = port->serial;
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
+	speed_t	baud_sup;
+	speed_t baud;
 
 	baud = tty_get_baud_rate(tty);
-	dev_dbg(&port->dev, "baud requested = %d\n", baud);
+	dev_dbg(&port->dev, "baud requested = %u\n", baud);
 	if (!baud)
 		return;
+
+	if (spriv->type->max_baud_rate)
+		baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
 	/*
-	 * There are two methods for setting/encoding the baud rate
-	 * 1) Direct method: encodes the baud rate value directly
-	 *    => supported by all chip types
-	 * 2) Divisor based method: encodes a divisor to a base value (12MHz*32)
-	 *    => supported by HX chips (and likely not by type_0/1 chips)
+	 * Set baud rate to nearest supported value.
 	 *
-	 * NOTE: Although the divisor based baud rate encoding method is much
-	 * more flexible, some of the standard baud rate values can not be
-	 * realized exactly. But the difference is very small (max. 0.2%) and
-	 * the device likely uses the same baud rate generator for both methods
-	 * so that there is likley no difference.
+	 * NOTE: Baud rate 500k can only be set using divisors.
 	 */
-	if (type == type_0 || type == type_1)
-		baud = pl2303_baudrate_encode_direct(baud, type, buf);
+	baud_sup = pl2303_get_supported_baud_rate(baud);
+
+	if (baud == 500000)
+		baud = pl2303_encode_baud_rate_divisor(buf, baud);
 	else
-		baud = pl2303_baudrate_encode_divisor(baud, type, buf);
+		baud = pl2303_encode_baud_rate_direct(buf, baud_sup);
+
 	/* Save resulting baud rate */
 	tty_encode_baud_rate(tty, baud, baud);
-	dev_dbg(&port->dev, "baud set = %d\n", baud);
+	dev_dbg(&port->dev, "baud set = %u\n", baud);
+}
+
+static int pl2303_get_line_request(struct usb_serial_port *port,
+							unsigned char buf[7])
+{
+	struct usb_device *udev = port->serial->dev;
+	int ret;
+
+	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
+				GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
+				0, 0, buf, 7, 100);
+	if (ret != 7) {
+		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
+
+		if (ret > 0)
+			ret = -EIO;
+
+		return ret;
+	}
+
+	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
+
+	return 0;
+}
+
+static int pl2303_set_line_request(struct usb_serial_port *port,
+							unsigned char buf[7])
+{
+	struct usb_device *udev = port->serial->dev;
+	int ret;
+
+	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+				SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
+				0, 0, buf, 7, 100);
+	if (ret != 7) {
+		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
+
+		if (ret > 0)
+			ret = -EIO;
+
+		return ret;
+	}
+
+	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
+
+	return 0;
 }
 
 static void pl2303_set_termios(struct tty_struct *tty,
@@ -477,51 +464,40 @@ static void pl2303_set_termios(struct tty_struct *tty,
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;
 	unsigned char *buf;
-	int i;
+	int ret;
 	u8 control;
 
-	/*
-	 * The PL2303 is reported to lose bytes if you change serial settings
-	 * even to the same values as before. Thus we actually need to filter
-	 * in this specific case.
-	 */
 	if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
 		return;
 
 	buf = kzalloc(7, GFP_KERNEL);
 	if (!buf) {
-		dev_err(&port->dev, "%s - out of memory.\n", __func__);
 		/* Report back no change occurred */
 		if (old_termios)
 			tty->termios = *old_termios;
 		return;
 	}
 
-	i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
-			    GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
-			    0, 0, buf, 7, 100);
-	dev_dbg(&port->dev, "0xa1:0x21:0:0  %d - %7ph\n", i, buf);
+	pl2303_get_line_request(port, buf);
 
-	if (C_CSIZE(tty)) {
-		switch (C_CSIZE(tty)) {
-		case CS5:
-			buf[6] = 5;
-			break;
-		case CS6:
-			buf[6] = 6;
-			break;
-		case CS7:
-			buf[6] = 7;
-			break;
-		default:
-		case CS8:
-			buf[6] = 8;
-		}
-		dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
+	switch (C_CSIZE(tty)) {
+	case CS5:
+		buf[6] = 5;
+		break;
+	case CS6:
+		buf[6] = 6;
+		break;
+	case CS7:
+		buf[6] = 7;
+		break;
+	default:
+	case CS8:
+		buf[6] = 8;
 	}
+	dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
 
-	/* For reference:   buf[0]:buf[3] baud rate value */
-	pl2303_encode_baudrate(tty, port, spriv->type, buf);
+	/* For reference buf[0]:buf[3] baud rate value */
+	pl2303_encode_baud_rate(tty, port, &buf[0]);
 
 	/* For reference buf[4]=0 is 1 stop bits */
 	/* For reference buf[4]=1 is 1.5 stop bits */
@@ -550,7 +526,7 @@ static void pl2303_set_termios(struct tty_struct *tty,
 		/* For reference buf[5]=3 is mark parity */
 		/* For reference buf[5]=4 is space parity */
 		if (C_PARODD(tty)) {
-			if (tty->termios.c_cflag & CMSPAR) {
+			if (C_CMSPAR(tty)) {
 				buf[5] = 3;
 				dev_dbg(&port->dev, "parity = mark\n");
 			} else {
@@ -558,7 +534,7 @@ static void pl2303_set_termios(struct tty_struct *tty,
 				dev_dbg(&port->dev, "parity = odd\n");
 			}
 		} else {
-			if (tty->termios.c_cflag & CMSPAR) {
+			if (C_CMSPAR(tty)) {
 				buf[5] = 4;
 				dev_dbg(&port->dev, "parity = space\n");
 			} else {
@@ -571,10 +547,23 @@ static void pl2303_set_termios(struct tty_struct *tty,
 		dev_dbg(&port->dev, "parity = none\n");
 	}
 
-	i = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-			    SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
-			    0, 0, buf, 7, 100);
-	dev_dbg(&port->dev, "0x21:0x20:0:0  %d\n", i);
+	/*
+	 * Some PL2303 are known to lose bytes if you change serial settings
+	 * even to the same values as before. Thus we actually need to filter
+	 * in this specific case.
+	 *
+	 * Note that the tty_termios_hw_change check above is not sufficient
+	 * as a previously requested baud rate may differ from the one
+	 * actually used (and stored in old_termios).
+	 *
+	 * NOTE: No additional locking needed for line_settings as it is
+	 *       only used in set_termios, which is serialised against itself.
+	 */
+	if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
+		ret = pl2303_set_line_request(port, buf);
+		if (!ret)
+			memcpy(priv->line_settings, buf, 7);
+	}
 
 	/* change control lines if we are switching to or from B0 */
 	spin_lock_irqsave(&priv->lock, flags);
@@ -591,19 +580,13 @@ static void pl2303_set_termios(struct tty_struct *tty,
 		spin_unlock_irqrestore(&priv->lock, flags);
 	}
 
-	memset(buf, 0, 7);
-	i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
-			    GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
-			    0, 0, buf, 7, 100);
-	dev_dbg(&port->dev, "0xa1:0x21:0:0  %d - %7ph\n", i, buf);
-
 	if (C_CRTSCTS(tty)) {
-		if (spriv->type == type_0 || spriv->type == type_1)
-			pl2303_vendor_write(0x0, 0x41, serial);
+		if (spriv->quirks & PL2303_QUIRK_LEGACY)
+			pl2303_vendor_write(serial, 0x0, 0x41);
 		else
-			pl2303_vendor_write(0x0, 0x61, serial);
+			pl2303_vendor_write(serial, 0x0, 0x61);
 	} else {
-		pl2303_vendor_write(0x0, 0x0, serial);
+		pl2303_vendor_write(serial, 0x0, 0x0);
 	}
 
 	kfree(buf);
@@ -616,13 +599,13 @@ static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
 	u8 control;
 
 	spin_lock_irqsave(&priv->lock, flags);
-	/* Change DTR and RTS */
 	if (on)
 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 	else
 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 	control = priv->line_control;
 	spin_unlock_irqrestore(&priv->lock, flags);
+
 	pl2303_set_control_lines(port, control);
 }
 
@@ -638,13 +621,13 @@ static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 	int result;
 
-	if (spriv->type == type_0 || spriv->type == type_1) {
+	if (spriv->quirks & PL2303_QUIRK_LEGACY) {
 		usb_clear_halt(serial->dev, port->write_urb->pipe);
 		usb_clear_halt(serial->dev, port->read_urb->pipe);
 	} else {
 		/* reset upstream data pipes */
-		pl2303_vendor_write(8, 0, serial);
-		pl2303_vendor_write(9, 0, serial);
+		pl2303_vendor_write(serial, 8, 0);
+		pl2303_vendor_write(serial, 9, 0);
 	}
 
 	/* Setup termios */
@@ -653,8 +636,8 @@ static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 
 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 	if (result) {
-		dev_err(&port->dev, "%s - failed submitting interrupt urb,"
-			" error %d\n", __func__, result);
+		dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
+			result);
 		return result;
 	}
 
@@ -724,48 +707,10 @@ static int pl2303_tiocmget(struct tty_struct *tty)
 static int pl2303_carrier_raised(struct usb_serial_port *port)
 {
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
+
 	if (priv->line_status & UART_DCD)
 		return 1;
-	return 0;
-}
 
-static int pl2303_tiocmiwait(struct tty_struct *tty, unsigned long arg)
-{
-	struct usb_serial_port *port = tty->driver_data;
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	unsigned long flags;
-	unsigned int prevstatus;
-	unsigned int status;
-	unsigned int changed;
-
-	spin_lock_irqsave(&priv->lock, flags);
-	prevstatus = priv->line_status;
-	spin_unlock_irqrestore(&priv->lock, flags);
-
-	while (1) {
-		interruptible_sleep_on(&port->port.delta_msr_wait);
-		/* see if a signal did it */
-		if (signal_pending(current))
-			return -ERESTARTSYS;
-
-		if (port->serial->disconnected)
-			return -EIO;
-
-		spin_lock_irqsave(&priv->lock, flags);
-		status = priv->line_status;
-		spin_unlock_irqrestore(&priv->lock, flags);
-
-		changed = prevstatus ^ status;
-
-		if (((arg & TIOCM_RNG) && (changed & UART_RING)) ||
-		    ((arg & TIOCM_DSR) && (changed & UART_DSR)) ||
-		    ((arg & TIOCM_CD)  && (changed & UART_DCD)) ||
-		    ((arg & TIOCM_CTS) && (changed & UART_CTS))) {
-			return 0;
-		}
-		prevstatus = status;
-	}
-	/* NOTREACHED */
 	return 0;
 }
 
@@ -775,8 +720,6 @@ static int pl2303_ioctl(struct tty_struct *tty,
 	struct serial_struct ser;
 	struct usb_serial_port *port = tty->driver_data;
 
-	dev_dbg(&port->dev, "%s cmd = 0x%04x\n", __func__, cmd);
-
 	switch (cmd) {
 	case TIOCGSERIAL:
 		memset(&ser, 0, sizeof ser);
@@ -790,9 +733,9 @@ static int pl2303_ioctl(struct tty_struct *tty,
 
 		return 0;
 	default:
-		dev_dbg(&port->dev, "%s not supported = 0x%04x\n", __func__, cmd);
 		break;
 	}
+
 	return -ENOIOCTLCMD;
 }
 
@@ -807,6 +750,7 @@ static void pl2303_break_ctl(struct tty_struct *tty, int break_state)
 		state = BREAK_OFF;
 	else
 		state = BREAK_ON;
+
 	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
 			state == BREAK_OFF ? "off" : "on");
 
@@ -821,48 +765,51 @@ static void pl2303_update_line_status(struct usb_serial_port *port,
 				      unsigned char *data,
 				      unsigned int actual_length)
 {
-
+	struct usb_serial *serial = port->serial;
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
 	struct tty_struct *tty;
 	unsigned long flags;
-	u8 status_idx = UART_STATE;
-	u8 length = UART_STATE + 1;
-	u8 prev_line_status;
-	u16 idv, idp;
-
-	idv = le16_to_cpu(port->serial->dev->descriptor.idVendor);
-	idp = le16_to_cpu(port->serial->dev->descriptor.idProduct);
+	unsigned int status_idx = UART_STATE_INDEX;
+	u8 status;
+	u8 delta;
 
+	if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
+		status_idx = 0;
 
-	if (idv == SIEMENS_VENDOR_ID) {
-		if (idp == SIEMENS_PRODUCT_ID_X65 ||
-		    idp == SIEMENS_PRODUCT_ID_SX1 ||
-		    idp == SIEMENS_PRODUCT_ID_X75) {
-
-			length = 1;
-			status_idx = 0;
-		}
-	}
-
-	if (actual_length < length)
+	if (actual_length < status_idx + 1)
 		return;
 
+	status = data[status_idx];
+
 	/* Save off the uart status for others to look at */
 	spin_lock_irqsave(&priv->lock, flags);
-	prev_line_status = priv->line_status;
-	priv->line_status = data[status_idx];
+	delta = priv->line_status ^ status;
+	priv->line_status = status;
 	spin_unlock_irqrestore(&priv->lock, flags);
-	if (priv->line_status & UART_BREAK_ERROR)
+
+	if (status & UART_BREAK_ERROR)
 		usb_serial_handle_break(port);
-	wake_up_interruptible(&port->port.delta_msr_wait);
 
-	tty = tty_port_tty_get(&port->port);
-	if (!tty)
-		return;
-	if ((priv->line_status ^ prev_line_status) & UART_DCD)
-		usb_serial_handle_dcd_change(port, tty,
-				priv->line_status & UART_DCD);
-	tty_kref_put(tty);
+	if (delta & UART_STATE_MSR_MASK) {
+		if (delta & UART_CTS)
+			port->icount.cts++;
+		if (delta & UART_DSR)
+			port->icount.dsr++;
+		if (delta & UART_RING)
+			port->icount.rng++;
+		if (delta & UART_DCD) {
+			port->icount.dcd++;
+			tty = tty_port_tty_get(&port->port);
+			if (tty) {
+				usb_serial_handle_dcd_change(port, tty,
+							status & UART_DCD);
+				tty_kref_put(tty);
+			}
+		}
+
+		wake_up_interruptible(&port->port.delta_msr_wait);
+	}
 }
 
 static void pl2303_read_int_callback(struct urb *urb)
@@ -897,10 +844,11 @@ static void pl2303_read_int_callback(struct urb *urb)
 
 exit:
 	retval = usb_submit_urb(urb, GFP_ATOMIC);
-	if (retval)
+	if (retval) {
 		dev_err(&port->dev,
 			"%s - usb_submit_urb failed with result %d\n",
 			__func__, retval);
+	}
 }
 
 static void pl2303_process_read_urb(struct urb *urb)
@@ -918,13 +866,14 @@ static void pl2303_process_read_urb(struct urb *urb)
 	line_status = priv->line_status;
 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
 	spin_unlock_irqrestore(&priv->lock, flags);
-	wake_up_interruptible(&port->port.delta_msr_wait);
 
 	if (!urb->actual_length)
 		return;
 
-	/* break takes precedence over parity, */
-	/* which takes precedence over framing errors */
+	/*
+	 * Break takes precedence over parity, which takes precedence over
+	 * framing errors.
+	 */
 	if (line_status & UART_BREAK_ERROR)
 		tty_flag = TTY_BREAK;
 	else if (line_status & UART_PARITY_ERROR)
@@ -952,7 +901,6 @@ static void pl2303_process_read_urb(struct urb *urb)
 	tty_flip_buffer_push(&port->port);
 }
 
-/* All of the device info needed for the PL2303 SIO serial converter */
 static struct usb_serial_driver pl2303_device = {
 	.driver = {
 		.owner =	THIS_MODULE,
@@ -964,16 +912,17 @@ static struct usb_serial_driver pl2303_device = {
 	.bulk_out_size =	256,
 	.open =			pl2303_open,
 	.close =		pl2303_close,
-	.dtr_rts = 		pl2303_dtr_rts,
+	.dtr_rts =		pl2303_dtr_rts,
 	.carrier_raised =	pl2303_carrier_raised,
 	.ioctl =		pl2303_ioctl,
 	.break_ctl =		pl2303_break_ctl,
 	.set_termios =		pl2303_set_termios,
 	.tiocmget =		pl2303_tiocmget,
 	.tiocmset =		pl2303_tiocmset,
-	.tiocmiwait =		pl2303_tiocmiwait,
+	.tiocmiwait =		usb_serial_generic_tiocmiwait,
 	.process_read_urb =	pl2303_process_read_urb,
 	.read_int_callback =	pl2303_read_int_callback,
+	.probe =		pl2303_probe,
 	.attach =		pl2303_startup,
 	.release =		pl2303_release,
 	.port_probe =		pl2303_port_probe,
@@ -986,5 +935,5 @@ static struct usb_serial_driver * const serial_drivers[] = {
 
 module_usb_serial_driver(serial_drivers, id_table);
 
-MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
 MODULE_LICENSE("GPL");