USB: serial: rename cp2101 driver to cp210x

Lots of users are getting confused about the cp2101 driver.  It really
does support more than just the cp2101 device, so rename it to cp210x to
try to prevent confusion.

Cc: Craig Shelley <craig@microtron.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 788 insertions, 0 deletions

diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
new file mode 100644
index 000000000000..2f23d0643624
--- /dev/null
+++ b/drivers/usb/serial/cp210x.c
@@ -0,0 +1,788 @@
+/*
+ * Silicon Laboratories CP2101/CP2102 USB to RS232 serial adaptor driver
+ *
+ * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License version
+ *      2 as published by the Free Software Foundation.
+ *
+ * Support to set flow control line levels using TIOCMGET and TIOCMSET
+ * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
+ * control thanks to Munir Nassar nassarmu@real-time.com
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/usb.h>
+#include <linux/uaccess.h>
+#include <linux/usb/serial.h>
+
+/*
+ * Version Information
+ */
+#define DRIVER_VERSION "v0.08"
+#define DRIVER_DESC "Silicon Labs CP2101/CP2102 RS232 serial adaptor driver"
+
+/*
+ * Function Prototypes
+ */
+static int cp2101_open(struct tty_struct *, struct usb_serial_port *,
+                                                        struct file *);
+static void cp2101_cleanup(struct usb_serial_port *);
+static void cp2101_close(struct tty_struct *, struct usb_serial_port *,
+                                                        struct file*);
+static void cp2101_get_termios(struct tty_struct *);
+static void cp2101_set_termios(struct tty_struct *, struct usb_serial_port *,
+                                                        struct ktermios*);
+static int cp2101_tiocmget(struct tty_struct *, struct file *);
+static int cp2101_tiocmset(struct tty_struct *, struct file *,
+                unsigned int, unsigned int);
+static void cp2101_break_ctl(struct tty_struct *, int);
+static int cp2101_startup(struct usb_serial *);
+static void cp2101_shutdown(struct usb_serial *);
+
+
+static int debug;
+
+static struct usb_device_id id_table [] = {
+        { USB_DEVICE(0x0471, 0x066A) }, /* AKTAKOM ACE-1001 cable */
+        { USB_DEVICE(0x0489, 0xE000) }, /* Pirelli Broadband S.p.A, DP-L10 SIP/GSM Mobile */
+        { USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
+        { USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
+        { USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
+        { USB_DEVICE(0x0FCF, 0x1006) }, /* Dynastream ANT development board */
+        { USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
+        { USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
+        { USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
+        { USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
+        { USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
+        { USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
+        { USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
+        { USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
+        { USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
+        { USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
+        { USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
+        { USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
+        { USB_DEVICE(0x10C4, 0x8115) }, /* Arygon NFC/Mifare Reader */
+        { USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
+        { USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
+        { USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
+        { USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
+        { USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
+        { USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
+        { USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
+        { USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
+        { USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
+        { USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
+        { USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
+        { USB_DEVICE(0x10C4, 0x822B) }, /* Modem EDGE(GSM) Comander 2 */
+        { USB_DEVICE(0x10C4, 0x826B) }, /* Cygnal Integrated Products, Inc., Fasttrax GPS demostration module */
+        { USB_DEVICE(0x10c4, 0x8293) }, /* Telegesys ETRX2USB */
+        { USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
+        { USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
+        { USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
+        { USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
+        { USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
+        { USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
+        { USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
+        { USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
+        { USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
+        { USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
+        { USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
+        { USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
+        { USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
+        { } /* Terminating Entry */
+};
+
+MODULE_DEVICE_TABLE(usb, id_table);
+
+static struct usb_driver cp2101_driver = {
+        .name           = "cp2101",
+        .probe          = usb_serial_probe,
+        .disconnect     = usb_serial_disconnect,
+        .id_table       = id_table,
+        .no_dynamic_id  =       1,
+};
+
+static struct usb_serial_driver cp2101_device = {
+        .driver = {
+                .owner =        THIS_MODULE,
+                .name =         "cp2101",
+        },
+        .usb_driver             = &cp2101_driver,
+        .id_table               = id_table,
+        .num_ports              = 1,
+        .open                   = cp2101_open,
+        .close                  = cp2101_close,
+        .break_ctl              = cp2101_break_ctl,
+        .set_termios            = cp2101_set_termios,
+        .tiocmget               = cp2101_tiocmget,
+        .tiocmset               = cp2101_tiocmset,
+        .attach                 = cp2101_startup,
+        .shutdown               = cp2101_shutdown,
+};
+
+/* Config request types */
+#define REQTYPE_HOST_TO_DEVICE  0x41
+#define REQTYPE_DEVICE_TO_HOST  0xc1
+
+/* Config SET requests. To GET, add 1 to the request number */
+#define CP2101_UART             0x00    /* Enable / Disable */
+#define CP2101_BAUDRATE         0x01    /* (BAUD_RATE_GEN_FREQ / baudrate) */
+#define CP2101_BITS             0x03    /* 0x(0)(databits)(parity)(stopbits) */
+#define CP2101_BREAK            0x05    /* On / Off */
+#define CP2101_CONTROL          0x07    /* Flow control line states */
+#define CP2101_MODEMCTL         0x13    /* Modem controls */
+#define CP2101_CONFIG_6         0x19    /* 6 bytes of config data ??? */
+
+/* CP2101_UART */
+#define UART_ENABLE             0x0001
+#define UART_DISABLE            0x0000
+
+/* CP2101_BAUDRATE */
+#define BAUD_RATE_GEN_FREQ      0x384000
+
+/* CP2101_BITS */
+#define BITS_DATA_MASK          0X0f00
+#define BITS_DATA_5             0X0500
+#define BITS_DATA_6             0X0600
+#define BITS_DATA_7             0X0700
+#define BITS_DATA_8             0X0800
+#define BITS_DATA_9             0X0900
+
+#define BITS_PARITY_MASK        0x00f0
+#define BITS_PARITY_NONE        0x0000
+#define BITS_PARITY_ODD         0x0010
+#define BITS_PARITY_EVEN        0x0020
+#define BITS_PARITY_MARK        0x0030
+#define BITS_PARITY_SPACE       0x0040
+
+#define BITS_STOP_MASK          0x000f
+#define BITS_STOP_1             0x0000
+#define BITS_STOP_1_5           0x0001
+#define BITS_STOP_2             0x0002
+
+/* CP2101_BREAK */
+#define BREAK_ON                0x0000
+#define BREAK_OFF               0x0001
+
+/* CP2101_CONTROL */
+#define CONTROL_DTR             0x0001
+#define CONTROL_RTS             0x0002
+#define CONTROL_CTS             0x0010
+#define CONTROL_DSR             0x0020
+#define CONTROL_RING            0x0040
+#define CONTROL_DCD             0x0080
+#define CONTROL_WRITE_DTR       0x0100
+#define CONTROL_WRITE_RTS       0x0200
+
+/*
+ * cp2101_get_config
+ * Reads from the CP2101 configuration registers
+ * 'size' is specified in bytes.
+ * 'data' is a pointer to a pre-allocated array of integers large
+ * enough to hold 'size' bytes (with 4 bytes to each integer)
+ */
+static int cp2101_get_config(struct usb_serial_port *port, u8 request,
+                unsigned int *data, int size)
+{
+        struct usb_serial *serial = port->serial;
+        __le32 *buf;
+        int result, i, length;
+
+        /* Number of integers required to contain the array */
+        length = (((size - 1) | 3) + 1)/4;
+
+        buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
+        if (!buf) {
+                dev_err(&port->dev, "%s - out of memory.\n", __func__);
+                return -ENOMEM;
+        }
+
+        /* For get requests, the request number must be incremented */
+        request++;
+
+        /* Issue the request, attempting to read 'size' bytes */
+        result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
+                                request, REQTYPE_DEVICE_TO_HOST, 0x0000,
+                                0, buf, size, 300);
+
+        /* Convert data into an array of integers */
+        for (i = 0; i < length; i++)
+                data[i] = le32_to_cpu(buf[i]);
+
+        kfree(buf);
+
+        if (result != size) {
+                dbg("%s - Unable to send config request, "
+                                "request=0x%x size=%d result=%d\n",
+                                __func__, request, size, result);
+                return -EPROTO;
+        }
+
+        return 0;
+}
+
+/*
+ * cp2101_set_config
+ * Writes to the CP2101 configuration registers
+ * Values less than 16 bits wide are sent directly
+ * 'size' is specified in bytes.
+ */
+static int cp2101_set_config(struct usb_serial_port *port, u8 request,
+                unsigned int *data, int size)
+{
+        struct usb_serial *serial = port->serial;
+        __le32 *buf;
+        int result, i, length;
+
+        /* Number of integers required to contain the array */
+        length = (((size - 1) | 3) + 1)/4;
+
+        buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
+        if (!buf) {
+                dev_err(&port->dev, "%s - out of memory.\n",
+                                __func__);
+                return -ENOMEM;
+        }
+
+        /* Array of integers into bytes */
+        for (i = 0; i < length; i++)
+                buf[i] = cpu_to_le32(data[i]);
+
+        if (size > 2) {
+                result = usb_control_msg(serial->dev,
+                                usb_sndctrlpipe(serial->dev, 0),
+                                request, REQTYPE_HOST_TO_DEVICE, 0x0000,
+                                0, buf, size, 300);
+        } else {
+                result = usb_control_msg(serial->dev,
+                                usb_sndctrlpipe(serial->dev, 0),
+                                request, REQTYPE_HOST_TO_DEVICE, data[0],
+                                0, NULL, 0, 300);
+        }
+
+        kfree(buf);
+
+        if ((size > 2 && result != size) || result < 0) {
+                dbg("%s - Unable to send request, "
+                                "request=0x%x size=%d result=%d\n",
+                                __func__, request, size, result);
+                return -EPROTO;
+        }
+
+        /* Single data value */
+        result = usb_control_msg(serial->dev,
+                        usb_sndctrlpipe(serial->dev, 0),
+                        request, REQTYPE_HOST_TO_DEVICE, data[0],
+                        0, NULL, 0, 300);
+        return 0;
+}
+
+/*
+ * cp2101_set_config_single
+ * Convenience function for calling cp2101_set_config on single data values
+ * without requiring an integer pointer
+ */
+static inline int cp2101_set_config_single(struct usb_serial_port *port,
+                u8 request, unsigned int data)
+{
+        return cp2101_set_config(port, request, &data, 2);
+}
+
+/*
+ * cp2101_quantise_baudrate
+ * Quantises the baud rate as per AN205 Table 1
+ */
+static unsigned int cp2101_quantise_baudrate(unsigned int baud) {
+        if      (baud <= 56)       baud = 0;
+        else if (baud <= 300)      baud = 300;
+        else if (baud <= 600)      baud = 600;
+        else if (baud <= 1200)     baud = 1200;
+        else if (baud <= 1800)     baud = 1800;
+        else if (baud <= 2400)     baud = 2400;
+        else if (baud <= 4000)     baud = 4000;
+        else if (baud <= 4803)     baud = 4800;
+        else if (baud <= 7207)     baud = 7200;
+        else if (baud <= 9612)     baud = 9600;
+        else if (baud <= 14428)    baud = 14400;
+        else if (baud <= 16062)    baud = 16000;
+        else if (baud <= 19250)    baud = 19200;
+        else if (baud <= 28912)    baud = 28800;
+        else if (baud <= 38601)    baud = 38400;
+        else if (baud <= 51558)    baud = 51200;
+        else if (baud <= 56280)    baud = 56000;
+        else if (baud <= 58053)    baud = 57600;
+        else if (baud <= 64111)    baud = 64000;
+        else if (baud <= 77608)    baud = 76800;
+        else if (baud <= 117028)   baud = 115200;
+        else if (baud <= 129347)   baud = 128000;
+        else if (baud <= 156868)   baud = 153600;
+        else if (baud <= 237832)   baud = 230400;
+        else if (baud <= 254234)   baud = 250000;
+        else if (baud <= 273066)   baud = 256000;
+        else if (baud <= 491520)   baud = 460800;
+        else if (baud <= 567138)   baud = 500000;
+        else if (baud <= 670254)   baud = 576000;
+        else if (baud <= 1053257)  baud = 921600;
+        else if (baud <= 1474560)  baud = 1228800;
+        else if (baud <= 2457600)  baud = 1843200;
+        else                       baud = 3686400;
+        return baud;
+}
+
+static int cp2101_open(struct tty_struct *tty, struct usb_serial_port *port,
+                                struct file *filp)
+{
+        struct usb_serial *serial = port->serial;
+        int result;
+
+        dbg("%s - port %d", __func__, port->number);
+
+        if (cp2101_set_config_single(port, CP2101_UART, UART_ENABLE)) {
+                dev_err(&port->dev, "%s - Unable to enable UART\n",
+                                __func__);
+                return -EPROTO;
+        }
+
+        /* Start reading from the device */
+        usb_fill_bulk_urb(port->read_urb, serial->dev,
+                        usb_rcvbulkpipe(serial->dev,
+                        port->bulk_in_endpointAddress),
+                        port->read_urb->transfer_buffer,
+                        port->read_urb->transfer_buffer_length,
+                        serial->type->read_bulk_callback,
+                        port);
+        result = usb_submit_urb(port->read_urb, GFP_KERNEL);
+        if (result) {
+                dev_err(&port->dev, "%s - failed resubmitting read urb, "
+                                "error %d\n", __func__, result);
+                return result;
+        }
+
+        /* Configure the termios structure */
+        cp2101_get_termios(tty);
+
+        /* Set the DTR and RTS pins low */
+        cp2101_tiocmset(tty, NULL, TIOCM_DTR | TIOCM_RTS, 0);
+
+        return 0;
+}
+
+static void cp2101_cleanup(struct usb_serial_port *port)
+{
+        struct usb_serial *serial = port->serial;
+
+        dbg("%s - port %d", __func__, port->number);
+
+        if (serial->dev) {
+                /* shutdown any bulk reads that might be going on */
+                if (serial->num_bulk_out)
+                        usb_kill_urb(port->write_urb);
+                if (serial->num_bulk_in)
+                        usb_kill_urb(port->read_urb);
+        }
+}
+
+static void cp2101_close(struct tty_struct *tty, struct usb_serial_port *port,
+                                        struct file *filp)
+{
+        dbg("%s - port %d", __func__, port->number);
+
+        /* shutdown our urbs */
+        dbg("%s - shutting down urbs", __func__);
+        usb_kill_urb(port->write_urb);
+        usb_kill_urb(port->read_urb);
+
+        mutex_lock(&port->serial->disc_mutex);
+        if (!port->serial->disconnected)
+                cp2101_set_config_single(port, CP2101_UART, UART_DISABLE);
+        mutex_unlock(&port->serial->disc_mutex);
+}
+
+/*
+ * cp2101_get_termios
+ * Reads the baud rate, data bits, parity, stop bits and flow control mode
+ * from the device, corrects any unsupported values, and configures the
+ * termios structure to reflect the state of the device
+ */
+static void cp2101_get_termios (struct tty_struct *tty)
+{
+        struct usb_serial_port *port = tty->driver_data;
+        unsigned int cflag, modem_ctl[4];
+        unsigned int baud;
+        unsigned int bits;
+
+        dbg("%s - port %d", __func__, port->number);
+
+        cp2101_get_config(port, CP2101_BAUDRATE, &baud, 2);
+        /* Convert to baudrate */
+        if (baud)
+                baud = cp2101_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud);
+
+        dbg("%s - baud rate = %d", __func__, baud);
+
+        tty_encode_baud_rate(tty, baud, baud);
+        cflag = tty->termios->c_cflag;
+
+        cp2101_get_config(port, CP2101_BITS, &bits, 2);
+        cflag &= ~CSIZE;
+        switch (bits & BITS_DATA_MASK) {
+        case BITS_DATA_5:
+                dbg("%s - data bits = 5", __func__);
+                cflag |= CS5;
+                break;
+        case BITS_DATA_6:
+                dbg("%s - data bits = 6", __func__);
+                cflag |= CS6;
+                break;
+        case BITS_DATA_7:
+                dbg("%s - data bits = 7", __func__);
+                cflag |= CS7;
+                break;
+        case BITS_DATA_8:
+                dbg("%s - data bits = 8", __func__);
+                cflag |= CS8;
+                break;
+        case BITS_DATA_9:
+                dbg("%s - data bits = 9 (not supported, using 8 data bits)",
+                                                                __func__);
+                cflag |= CS8;
+                bits &= ~BITS_DATA_MASK;
+                bits |= BITS_DATA_8;
+                cp2101_set_config(port, CP2101_BITS, &bits, 2);
+                break;
+        default:
+                dbg("%s - Unknown number of data bits, using 8", __func__);
+                cflag |= CS8;
+                bits &= ~BITS_DATA_MASK;
+                bits |= BITS_DATA_8;
+                cp2101_set_config(port, CP2101_BITS, &bits, 2);
+                break;
+        }
+
+        switch (bits & BITS_PARITY_MASK) {
+        case BITS_PARITY_NONE:
+                dbg("%s - parity = NONE", __func__);
+                cflag &= ~PARENB;
+                break;
+        case BITS_PARITY_ODD:
+                dbg("%s - parity = ODD", __func__);
+                cflag |= (PARENB|PARODD);
+                break;
+        case BITS_PARITY_EVEN:
+                dbg("%s - parity = EVEN", __func__);
+                cflag &= ~PARODD;
+                cflag |= PARENB;
+                break;
+        case BITS_PARITY_MARK:
+                dbg("%s - parity = MARK (not supported, disabling parity)",
+                                __func__);
+                cflag &= ~PARENB;
+                bits &= ~BITS_PARITY_MASK;
+                cp2101_set_config(port, CP2101_BITS, &bits, 2);
+                break;
+        case BITS_PARITY_SPACE:
+                dbg("%s - parity = SPACE (not supported, disabling parity)",
+                                __func__);
+                cflag &= ~PARENB;
+                bits &= ~BITS_PARITY_MASK;
+                cp2101_set_config(port, CP2101_BITS, &bits, 2);
+                break;
+        default:
+                dbg("%s - Unknown parity mode, disabling parity", __func__);
+                cflag &= ~PARENB;
+                bits &= ~BITS_PARITY_MASK;
+                cp2101_set_config(port, CP2101_BITS, &bits, 2);
+                break;
+        }
+
+        cflag &= ~CSTOPB;
+        switch (bits & BITS_STOP_MASK) {
+        case BITS_STOP_1:
+                dbg("%s - stop bits = 1", __func__);
+                break;
+        case BITS_STOP_1_5:
+                dbg("%s - stop bits = 1.5 (not supported, using 1 stop bit)",
+                                                                __func__);
+                bits &= ~BITS_STOP_MASK;
+                cp2101_set_config(port, CP2101_BITS, &bits, 2);
+                break;
+        case BITS_STOP_2:
+                dbg("%s - stop bits = 2", __func__);
+                cflag |= CSTOPB;
+                break;
+        default:
+                dbg("%s - Unknown number of stop bits, using 1 stop bit",
+                                                                __func__);
+                bits &= ~BITS_STOP_MASK;
+                cp2101_set_config(port, CP2101_BITS, &bits, 2);
+                break;
+        }
+
+        cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
+        if (modem_ctl[0] & 0x0008) {
+                dbg("%s - flow control = CRTSCTS", __func__);
+                cflag |= CRTSCTS;
+        } else {
+                dbg("%s - flow control = NONE", __func__);
+                cflag &= ~CRTSCTS;
+        }
+
+        tty->termios->c_cflag = cflag;
+}
+
+static void cp2101_set_termios(struct tty_struct *tty,
+                struct usb_serial_port *port, struct ktermios *old_termios)
+{
+        unsigned int cflag, old_cflag;
+        unsigned int baud = 0, bits;
+        unsigned int modem_ctl[4];
+
+        dbg("%s - port %d", __func__, port->number);
+
+        if (!tty)
+                return;
+
+        tty->termios->c_cflag &= ~CMSPAR;
+        cflag = tty->termios->c_cflag;
+        old_cflag = old_termios->c_cflag;
+        baud = cp2101_quantise_baudrate(tty_get_baud_rate(tty));
+
+        /* If the baud rate is to be updated*/
+        if (baud != tty_termios_baud_rate(old_termios) && baud != 0) {
+                dbg("%s - Setting baud rate to %d baud", __func__,
+                                baud);
+                if (cp2101_set_config_single(port, CP2101_BAUDRATE,
+                                        ((BAUD_RATE_GEN_FREQ + baud/2) / baud))) {
+                        dbg("Baud rate requested not supported by device\n");
+                        baud = tty_termios_baud_rate(old_termios);
+                }
+        }
+        /* Report back the resulting baud rate */
+        tty_encode_baud_rate(tty, baud, baud);
+
+        /* If the number of data bits is to be updated */
+        if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
+                cp2101_get_config(port, CP2101_BITS, &bits, 2);
+                bits &= ~BITS_DATA_MASK;
+                switch (cflag & CSIZE) {
+                case CS5:
+                        bits |= BITS_DATA_5;
+                        dbg("%s - data bits = 5", __func__);
+                        break;
+                case CS6:
+                        bits |= BITS_DATA_6;
+                        dbg("%s - data bits = 6", __func__);
+                        break;
+                case CS7:
+                        bits |= BITS_DATA_7;
+                        dbg("%s - data bits = 7", __func__);
+                        break;
+                case CS8:
+                        bits |= BITS_DATA_8;
+                        dbg("%s - data bits = 8", __func__);
+                        break;
+                /*case CS9:
+                        bits |= BITS_DATA_9;
+                        dbg("%s - data bits = 9", __func__);
+                        break;*/
+                default:
+                        dbg("cp2101 driver does not "
+                                        "support the number of bits requested,"
+                                        " using 8 bit mode\n");
+                                bits |= BITS_DATA_8;
+                                break;
+                }
+                if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
+                        dbg("Number of data bits requested "
+                                        "not supported by device\n");
+        }
+
+        if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
+                cp2101_get_config(port, CP2101_BITS, &bits, 2);
+                bits &= ~BITS_PARITY_MASK;
+                if (cflag & PARENB) {
+                        if (cflag & PARODD) {
+                                bits |= BITS_PARITY_ODD;
+                                dbg("%s - parity = ODD", __func__);
+                        } else {
+                                bits |= BITS_PARITY_EVEN;
+                                dbg("%s - parity = EVEN", __func__);
+                        }
+                }
+                if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
+                        dbg("Parity mode not supported "
+                                        "by device\n");
+        }
+
+        if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
+                cp2101_get_config(port, CP2101_BITS, &bits, 2);
+                bits &= ~BITS_STOP_MASK;
+                if (cflag & CSTOPB) {
+                        bits |= BITS_STOP_2;
+                        dbg("%s - stop bits = 2", __func__);
+                } else {
+                        bits |= BITS_STOP_1;
+                        dbg("%s - stop bits = 1", __func__);
+                }
+                if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
+                        dbg("Number of stop bits requested "
+                                        "not supported by device\n");
+        }
+
+        if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
+                cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
+                dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
+                                __func__, modem_ctl[0], modem_ctl[1],
+                                modem_ctl[2], modem_ctl[3]);
+
+                if (cflag & CRTSCTS) {
+                        modem_ctl[0] &= ~0x7B;
+                        modem_ctl[0] |= 0x09;
+                        modem_ctl[1] = 0x80;
+                        dbg("%s - flow control = CRTSCTS", __func__);
+                } else {
+                        modem_ctl[0] &= ~0x7B;
+                        modem_ctl[0] |= 0x01;
+                        modem_ctl[1] |= 0x40;
+                        dbg("%s - flow control = NONE", __func__);
+                }
+
+                dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
+                                __func__, modem_ctl[0], modem_ctl[1],
+                                modem_ctl[2], modem_ctl[3]);
+                cp2101_set_config(port, CP2101_MODEMCTL, modem_ctl, 16);
+        }
+
+}
+
+static int cp2101_tiocmset (struct tty_struct *tty, struct file *file,
+                unsigned int set, unsigned int clear)
+{
+        struct usb_serial_port *port = tty->driver_data;
+        unsigned int control = 0;
+
+        dbg("%s - port %d", __func__, port->number);
+
+        if (set & TIOCM_RTS) {
+                control |= CONTROL_RTS;
+                control |= CONTROL_WRITE_RTS;
+        }
+        if (set & TIOCM_DTR) {
+                control |= CONTROL_DTR;
+                control |= CONTROL_WRITE_DTR;
+        }
+        if (clear & TIOCM_RTS) {
+                control &= ~CONTROL_RTS;
+                control |= CONTROL_WRITE_RTS;
+        }
+        if (clear & TIOCM_DTR) {
+                control &= ~CONTROL_DTR;
+                control |= CONTROL_WRITE_DTR;
+        }
+
+        dbg("%s - control = 0x%.4x", __func__, control);
+
+        return cp2101_set_config(port, CP2101_CONTROL, &control, 2);
+
+}
+
+static int cp2101_tiocmget (struct tty_struct *tty, struct file *file)
+{
+        struct usb_serial_port *port = tty->driver_data;
+        unsigned int control;
+        int result;
+
+        dbg("%s - port %d", __func__, port->number);
+
+        cp2101_get_config(port, CP2101_CONTROL, &control, 1);
+
+        result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
+                |((control & CONTROL_RTS) ? TIOCM_RTS : 0)
+                |((control & CONTROL_CTS) ? TIOCM_CTS : 0)
+                |((control & CONTROL_DSR) ? TIOCM_DSR : 0)
+                |((control & CONTROL_RING)? TIOCM_RI  : 0)
+                |((control & CONTROL_DCD) ? TIOCM_CD  : 0);
+
+        dbg("%s - control = 0x%.2x", __func__, control);
+
+        return result;
+}
+
+static void cp2101_break_ctl (struct tty_struct *tty, int break_state)
+{
+        struct usb_serial_port *port = tty->driver_data;
+        unsigned int state;
+
+        dbg("%s - port %d", __func__, port->number);
+        if (break_state == 0)
+                state = BREAK_OFF;
+        else
+                state = BREAK_ON;
+        dbg("%s - turning break %s", __func__,
+                        state == BREAK_OFF ? "off" : "on");
+        cp2101_set_config(port, CP2101_BREAK, &state, 2);
+}
+
+static int cp2101_startup(struct usb_serial *serial)
+{
+        /* CP2101 buffers behave strangely unless device is reset */
+        usb_reset_device(serial->dev);
+        return 0;
+}
+
+static void cp2101_shutdown(struct usb_serial *serial)
+{
+        int i;
+
+        dbg("%s", __func__);
+
+        /* Stop reads and writes on all ports */
+        for (i = 0; i < serial->num_ports; ++i)
+                cp2101_cleanup(serial->port[i]);
+}
+
+static int __init cp2101_init(void)
+{
+        int retval;
+
+        retval = usb_serial_register(&cp2101_device);
+        if (retval)
+                return retval; /* Failed to register */
+
+        retval = usb_register(&cp2101_driver);
+        if (retval) {
+                /* Failed to register */
+                usb_serial_deregister(&cp2101_device);
+                return retval;
+        }
+
+        /* Success */
+        printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
+               DRIVER_DESC "\n");
+        return 0;
+}
+
+static void __exit cp2101_exit(void)
+{
+        usb_deregister(&cp2101_driver);
+        usb_serial_deregister(&cp2101_device);
+}
+
+module_init(cp2101_init);
+module_exit(cp2101_exit);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+
+module_param(debug, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Enable verbose debugging messages");