]> oss.titaniummirror.com Git - cp210x.git/commitdiff
Support for natty
authorR. Steve McKown <rsmckown@gmail.com>
Thu, 8 Sep 2011 15:25:02 +0000 (09:25 -0600)
committerR. Steve McKown <rsmckown@gmail.com>
Thu, 8 Sep 2011 15:36:12 +0000 (09:36 -0600)
There's no change, but to ensure that the same module code used in Maverick
is used in natty.

src/cp210x.c.natty [new file with mode: 0644]

diff --git a/src/cp210x.c.natty b/src/cp210x.c.natty
new file mode 100644 (file)
index 0000000..d88d980
--- /dev/null
@@ -0,0 +1,1309 @@
+/*
+ * Silicon Laboratories CP210x 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>
+#include "cp210x.h"
+
+/*
+ * Version Information
+ */
+#define DRIVER_VERSION "vxxDEBVERxx"
+#define DRIVER_DESC "Silicon Labs CP210x RS232 serial adaptor driver"
+
+/*
+ * Function Prototypes
+ */
+static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *);
+static void cp210x_close(struct usb_serial_port *);
+static void cp210x_get_termios(struct tty_struct *,
+       struct usb_serial_port *port);
+static void cp210x_get_termios_port(struct usb_serial_port *port,
+       unsigned int *cflagp, unsigned int *baudp);
+static void cp210x_set_termios(struct tty_struct *, struct usb_serial_port *,
+                                                       struct ktermios*);
+static int cp210x_tiocmget(struct tty_struct *, struct file *);
+static int cp210x_tiocmset(struct tty_struct *, struct file *,
+               unsigned int, unsigned int);
+static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *,
+               unsigned int, unsigned int);
+static void cp210x_break_ctl(struct tty_struct *, int);
+static int cp210x_startup(struct usb_serial *);
+static int cp210x_ioctl(struct tty_struct *, struct file *,
+               unsigned int, unsigned long);
+static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
+static int cp210x_carrier_raised(struct usb_serial_port *p);
+
+static int debug;
+
+static const 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(0x0745, 0x1000) }, /* CipherLab USB CCD Barcode Scanner 1000 */
+       { USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
+       { USB_DEVICE(0x08FD, 0x000A) }, /* Digianswer A/S , ZigBee/802.15.4 MAC Device */
+       { USB_DEVICE(0x0BED, 0x1100) }, /* MEI (TM) Cashflow-SC Bill/Voucher Acceptor */
+       { USB_DEVICE(0x0BED, 0x1101) }, /* MEI series 2000 Combo Acceptor */
+       { 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, 0x0F91) }, /* Vstabi */
+       { USB_DEVICE(0x10C4, 0x1101) }, /* Arkham Technology DS101 Bus Monitor */
+       { USB_DEVICE(0x10C4, 0x1601) }, /* Arkham Technology DS101 Adapter */
+       { USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
+       { USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
+       { USB_DEVICE(0x10C4, 0x8044) }, /* Cygnal Debug Adapter */
+       { USB_DEVICE(0x10C4, 0x804E) }, /* Software Bisque Paramount ME build-in converter */
+       { USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
+       { USB_DEVICE(0x10C4, 0x8054) }, /* Enfora GSM2228 */
+       { USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
+       { USB_DEVICE(0x10C4, 0x806F) }, /* IMS USB to RS422 Converter Cable */
+       { 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, 0x813F) }, /* Tams Master Easy Control */
+       { USB_DEVICE(0x10C4, 0x8149) }, /* West Mountain Radio Computerized Battery Analyzer */
+       { 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, 0x818B) }, /* AVIT Research USB to TTL */
+       { USB_DEVICE(0x10C4, 0x819F) }, /* MJS USB Toslink Switcher */
+       { USB_DEVICE(0x10C4, 0x81A6) }, /* ThinkOptics WavIt */
+       { USB_DEVICE(0x10C4, 0x81AC) }, /* MSD Dash Hawk */
+       { USB_DEVICE(0x10C4, 0x81AD) }, /* INSYS USB Modem */
+       { 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, 0x81E8) }, /* Zephyr Bioharness */
+       { USB_DEVICE(0x10C4, 0x81F2) }, /* C1007 HF band RFID controller */
+       { 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, 0x82F9) }, /* Procyon AVS */
+       { USB_DEVICE(0x10C4, 0x8341) }, /* Siemens MC35PU GPRS Modem */
+       { USB_DEVICE(0x10C4, 0x8382) }, /* Cygnal Integrated Products, Inc. */
+       { USB_DEVICE(0x10C4, 0x83A8) }, /* Amber Wireless AMB2560 */
+       { USB_DEVICE(0x10C4, 0x8411) }, /* Kyocera GPS Module */
+       { USB_DEVICE(0x10C4, 0x846E) }, /* BEI USB Sensor Interface (VCP) */
+       { USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
+       { USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
+       { USB_DEVICE(0x10C4, 0xEA71) }, /* Infinity GPS-MIC-1 Radio Monophone */
+       { 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(0x10CE, 0xEA6A) }, /* Silicon Labs MobiData GPRS USB Modem 100EU */
+       { USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
+       { USB_DEVICE(0x1555, 0x0004) }, /* Owen AC4 USB-RS485 Converter */
+       { USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
+       { USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
+       { USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
+       { USB_DEVICE(0x1843, 0x0200) }, /* Vaisala USB Instrument Cable */
+       { USB_DEVICE(0x18EF, 0xE00F) }, /* ELV USB-I2C-Interface */
+       { USB_DEVICE(0x413C, 0x9500) }, /* DW700 GPS USB interface */
+       { } /* Terminating Entry */
+};
+
+MODULE_DEVICE_TABLE(usb, id_table);
+
+static struct usb_driver cp210x_driver = {
+       .name           = "cp210x",
+       .probe          = usb_serial_probe,
+       .disconnect     = usb_serial_disconnect,
+       .id_table       = id_table,
+       .no_dynamic_id  =       1,
+};
+
+static struct usb_serial_driver cp210x_device = {
+       .driver = {
+               .owner =        THIS_MODULE,
+               .name =         "cp210x",
+       },
+       .usb_driver             = &cp210x_driver,
+       .id_table               = id_table,
+       .num_ports              = 1,
+       .bulk_in_size           = 256,
+       .bulk_out_size          = 256,
+       .open                   = cp210x_open,
+       .close                  = cp210x_close,
+       .ioctl                  = cp210x_ioctl,
+       .break_ctl              = cp210x_break_ctl,
+       .set_termios            = cp210x_set_termios,
+       .tiocmget               = cp210x_tiocmget,
+       .tiocmset               = cp210x_tiocmset,
+       .attach                 = cp210x_startup,
+       .dtr_rts                = cp210x_dtr_rts,
+       .carrier_raised         = cp210x_carrier_raised
+};
+
+/* Config request codes */
+#define CP210X_IFC_ENABLE      0x00
+#define CP210X_SET_BAUDDIV     0x01
+#define CP210X_GET_BAUDDIV     0x02
+#define CP210X_SET_LINE_CTL    0x03
+#define CP210X_GET_LINE_CTL    0x04
+#define CP210X_SET_BREAK       0x05
+#define CP210X_IMM_CHAR                0x06
+#define CP210X_SET_MHS         0x07
+#define CP210X_GET_MDMSTS      0x08
+#define CP210X_SET_XON         0x09
+#define CP210X_SET_XOFF                0x0A
+#define CP210X_SET_EVENTMASK   0x0B
+#define CP210X_GET_EVENTMASK   0x0C
+#define CP210X_SET_CHAR                0x0D
+#define CP210X_GET_CHARS       0x0E
+#define CP210X_GET_PROPS       0x0F
+#define CP210X_GET_COMM_STATUS 0x10
+#define CP210X_RESET           0x11
+#define CP210X_PURGE           0x12
+#define CP210X_SET_FLOW                0x13
+#define CP210X_GET_FLOW                0x14
+#define CP210X_EMBED_EVENTS    0x15
+#define CP210X_GET_EVENTSTATE  0x16
+#define CP210X_SET_CHARS       0x19
+
+/* CP210X_IFC_ENABLE */
+#define UART_ENABLE            0x0001
+#define UART_DISABLE           0x0000
+
+/* CP210X_(SET|GET)_BAUDDIV */
+#define BAUD_RATE_GEN_FREQ     0x384000
+
+/* CP210X_(SET|GET)_LINE_CTL */
+#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
+
+/* CP210X_SET_BREAK */
+#define BREAK_ON               0x0000
+#define BREAK_OFF              0x0001
+
+/* CP210X_(SET_MHS|GET_MDMSTS) */
+#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
+
+/* cp210x_get_partnum() return codes */
+#define CP210x_PART_UNKNOWN    0x00
+#define CP210x_PART_CP2101     0x01
+#define CP210x_PART_CP2102     0x02
+#define CP210x_PART_CP2103     0x03
+
+/* Taken from drivers/usb/gadget/usbstring.c */
+static int utf8_to_utf16le(const char *s, __le16 *cp, unsigned len)
+{
+       int     count = 0;
+       u8      c;
+       u16     uchar;
+
+       /* this insists on correct encodings, though not minimal ones.
+        * BUT it currently rejects legit 4-byte UTF-8 code points,
+        * which need surrogate pairs.  (Unicode 3.1 can use them.)
+        */
+       while (len != 0 && (c = (u8) *s++) != 0) {
+               if (unlikely(c & 0x80)) {
+                       // 2-byte sequence:
+                       // 00000yyyyyxxxxxx = 110yyyyy 10xxxxxx
+                       if ((c & 0xe0) == 0xc0) {
+                               uchar = (c & 0x1f) << 6;
+
+                               c = (u8) *s++;
+                               if ((c & 0xc0) != 0x80)
+                                       goto fail;
+                               c &= 0x3f;
+                               uchar |= c;
+
+                       // 3-byte sequence (most CJKV characters):
+                       // zzzzyyyyyyxxxxxx = 1110zzzz 10yyyyyy 10xxxxxx
+                       } else if ((c & 0xf0) == 0xe0) {
+                               uchar = (c & 0x0f) << 12;
+
+                               c = (u8) *s++;
+                               if ((c & 0xc0) != 0x80)
+                                       goto fail;
+                               c &= 0x3f;
+                               uchar |= c << 6;
+
+                               c = (u8) *s++;
+                               if ((c & 0xc0) != 0x80)
+                                       goto fail;
+                               c &= 0x3f;
+                               uchar |= c;
+
+                               /* no bogus surrogates */
+                               if (0xd800 <= uchar && uchar <= 0xdfff)
+                                       goto fail;
+
+                       // 4-byte sequence (surrogate pairs, currently rare):
+                       // 11101110wwwwzzzzyy + 110111yyyyxxxxxx
+                       //     = 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx
+                       // (uuuuu = wwww + 1)
+                       // FIXME accept the surrogate code points (only)
+
+                       } else
+                               goto fail;
+               } else
+                       uchar = c;
+               *cp++ = uchar;
+               count++;
+               len--;
+       }
+       return count;
+fail:
+       return -1;
+}
+
+
+/*
+ * make_usb_string
+ * Populates usbstr with: (len) + (USB_DT_STRING) + unicode(str).  Each char in
+ * usbstr consumes two bytes in unicode (__le16) format.
+ * Returns the resulting length of usbstr in bytes.
+ * This function can accept overlapping usbstr and str as long as the overlap
+ * does not cause data written to usbstr to overwrite data not yet read from
+ * str.
+ */
+static int make_usb_string(__le16* usbstr, size_t usblen, const char *src,
+               size_t srclen)
+{
+       int len;
+
+       /* string descriptors have length, type, then UTF16-LE text */
+       if (usblen > 254)
+               usblen = 254;
+       len = min(usblen / 2 - 1, srclen);
+       len = utf8_to_utf16le(src, usbstr + 1, len);
+       if (len >= 0) {
+               len = (len + 1) * 2;
+               ((u8 *)usbstr)[0] = len;
+               ((u8 *)usbstr)[1] = USB_DT_STRING;
+       }
+       return len;
+}
+
+/*
+ * cp210x_usbstr_from_user
+ * Populate kbuf with a usb string derived from a user space variable.  klen
+ * is the size of the buffer at kbuf.
+ * Returns the number of bytes used in kbuf.
+ */
+static size_t cp210x_usbstr_from_user(__le16 *kbuf,
+               struct cp210x_buffer __user *ubuf, size_t klen)
+{
+       struct cp210x_buffer t;
+       char *str;
+       size_t slen;
+
+       if (copy_from_user(&t, ubuf, sizeof(t)))
+               return -EINVAL;
+       slen = klen / 2 - 1;
+       if (!t.buf || !t.len || t.len > slen)
+               return -EINVAL;
+       if (t.len < slen)
+               slen = t.len;
+       str = (char *)kbuf + klen - slen;
+       if (copy_from_user(str, (__u8 __user *)t.buf, slen))
+               return -EINVAL;
+       return make_usb_string(kbuf, klen, str, slen);
+}
+
+/*
+ * cp210x_ctlmsg
+ * A generic usb control message interface.
+ * Returns the actual size of the data read or written within the message, 0
+ * if no data were read or written, or a negative value to indicate an error.
+ */
+static int cp210x_ctlmsg(struct usb_serial_port *port, u8 request,
+               u8 requestype, u16 value, u16 index, void *data, u16 size)
+{
+       struct usb_device *dev = port->serial->dev;
+       u8 *tbuf;
+       int ret;
+
+       tbuf = kmalloc(size, GFP_KERNEL);
+       if (!tbuf)
+               return -ENOMEM;
+       if (requestype & USB_DIR_IN) {
+               ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), request,
+                               requestype, value, index, tbuf, size, 300);
+               if (ret > 0 && size)
+                       memcpy(data, tbuf, size);
+       } else {
+               if (size)
+                       memcpy(tbuf, data, size);
+               ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), request,
+                               requestype, value, index, tbuf, size, 300);
+       }
+       kfree(tbuf);
+       if (ret < 0 && ret != -EPIPE) {
+               dev_printk(KERN_DEBUG, &dev->dev,
+                       "cp210x: ctl failed cmd rqt %u rq %u len %u ret %d\n",
+                       requestype, request, size, ret);
+       }
+       return ret;
+}
+
+static int cp210x_reset(struct usb_serial_port *port)
+{
+       dbg("%s", __func__);
+
+       /* Instructing the CP210X to reset seems to work more reliably than
+        * calling usb_reset_device().
+        */
+       cp210x_ctlmsg(port, 0xff, USB_TYPE_VENDOR,
+                       0x0008, 0x00, NULL, 0);
+       return 0;
+}
+
+static int cp210x_get_partnum(struct usb_serial_port *port)
+{
+       static u8 _partnum = CP210x_PART_UNKNOWN;
+
+       if (_partnum == CP210x_PART_UNKNOWN) {
+               u8 addr = port->serial->dev->actconfig->interface[0]->
+                       cur_altsetting->endpoint[0].desc.bEndpointAddress &
+                       USB_ENDPOINT_NUMBER_MASK;
+
+               if (addr == 0x03 || addr == 0x02)
+                       _partnum = CP210x_PART_CP2101;
+               else if (addr == 0x01) {
+                       /* Must query part to determine part number */
+                       if (cp210x_ctlmsg(port, 0xff,
+                                       USB_DIR_IN|USB_TYPE_VENDOR,
+                                       0x370b, 0x00, &_partnum, 1) != 1)
+                               _partnum = CP210x_PART_UNKNOWN;
+               }
+       }
+       dbg("%s - partnum %u", __func__, _partnum);
+       return _partnum;
+}
+
+static inline int cp210x_setu16(struct usb_serial_port *port, int cmd,
+               unsigned int value)
+{
+       return cp210x_ctlmsg(port, 0xff, USB_TYPE_VENDOR,
+                       0x3700 | (cmd & 0xff), value, NULL, 0);
+}
+
+/*
+ * cp210x_setstr
+ *
+ * Set a USB string descriptor using proprietary cp210x control messages.
+ * Return the number of characters actually written.
+ */
+static int cp210x_setstr(struct usb_serial_port *port, int cmd, __le16 *usbstr)
+{
+       int len = ((u8 *)usbstr)[0];
+       int ret = cp210x_ctlmsg(port, 0xff, USB_TYPE_VENDOR,
+                       0x3700 | (cmd & 0xff), 0, usbstr, len);
+       dbg("%s - cmd 0x%02x len %d ret %d", __func__, cmd, len, ret);
+       return ret;
+}
+
+/* Set all gpio simultaneously */
+static int cp210x_gpioset(struct usb_serial_port *port, u8 gpio)
+{
+       dbg("%s - port %d, gpio = 0x%.2x", __func__, port->number, gpio);
+
+       return cp210x_ctlmsg(port, 0xff, USB_TYPE_VENDOR,
+                       0x37e1, ((uint16_t)gpio << 8) | GPIO_MASK, NULL, 0);
+}
+
+/* Set select gpio bits */
+static int cp210x_gpiosetb(struct usb_serial_port *port, u8 set, u8 clear)
+{
+       u16 gpio = 0;
+
+       /* The bitmask is in the LSB, the values in the MSB */
+       if (set & GPIO_0)
+               gpio |= (GPIO_0 << 8)|GPIO_0;
+       if (set & GPIO_1)
+               gpio |= (GPIO_1 << 8)|GPIO_1;
+       if (set & GPIO_2)
+               gpio |= (GPIO_2 << 8)|GPIO_2;
+       if (set & GPIO_3)
+               gpio |= (GPIO_3 << 8)|GPIO_3;
+       if (clear & GPIO_0)
+               gpio = (gpio & ~(GPIO_0 << 8))|GPIO_0;
+       if (clear & GPIO_1)
+               gpio = (gpio & ~(GPIO_1 << 8))|GPIO_1;
+       if (clear & GPIO_2)
+               gpio = (gpio & ~(GPIO_2 << 8))|GPIO_2;
+       if (clear & GPIO_3)
+               gpio = (gpio & ~(GPIO_3 << 8))|GPIO_3;
+
+       dbg("%s - port %d, gpiob = 0x%.4x", __func__, port->number, gpio);
+
+       return cp210x_ctlmsg(port, 0xff, USB_TYPE_VENDOR,
+                       0x37e1, gpio, NULL, 0);
+}
+
+static int cp210x_gpioget(struct usb_serial_port *port, u8 *gpio)
+{
+       int ret;
+
+       dbg("%s - port %d", __func__, port->number);
+
+       ret = cp210x_ctlmsg(port, 0xff, USB_DIR_IN|USB_TYPE_VENDOR,
+                       0x00c2, 0, gpio, 1);
+
+       dbg("%s - gpio = 0x%.2x (%d)", __func__, *gpio, ret);
+
+       return (ret == 1) ? 0 : -1;
+}
+
+static int cp210x_portconfset(struct usb_serial_port *port,
+               struct cp210x_port_config *config)
+{
+       struct cp210x_port_config lconfig;
+       int ret;
+
+       dbg("%s", __func__);
+
+       memcpy(&lconfig, config, sizeof(lconfig));
+
+       /* Words from cp210x are MSB */
+       lconfig.reset.mode = cpu_to_be16(config->reset.mode);
+       lconfig.reset.latch = cpu_to_be16(config->reset.latch);
+       lconfig.suspend.mode = cpu_to_be16(config->suspend.mode);
+       lconfig.suspend.latch = cpu_to_be16(config->suspend.latch);
+       /* apparently not implemented by CP210X firmware */
+       lconfig.suspend.lowPower = 0;
+       lconfig.reset.lowPower = 0;
+
+       ret = cp210x_ctlmsg(port, 0xff, USB_TYPE_VENDOR, 0x370c,
+                       0, &lconfig, sizeof(struct cp210x_port_config));
+       if (ret == sizeof(struct cp210x_port_config))
+               return 0;
+       else if (ret >= 0)
+               return -1;
+       else
+               return ret;
+}
+
+static int cp210x_portconfget(struct usb_serial_port *port,
+               struct cp210x_port_config *config)
+{
+       int ret;
+
+       dbg("%s", __func__);
+
+       ret = cp210x_ctlmsg(port, 0xff, USB_DIR_IN|USB_TYPE_VENDOR,
+                       0x370c, 0, config, sizeof(struct cp210x_port_config));
+       if (ret == sizeof(struct cp210x_port_config)) {
+               /* Words from cp210x are MSB */
+               config->reset.mode = be16_to_cpu(config->reset.mode);
+               config->reset.lowPower = be16_to_cpu(config->reset.lowPower);
+               config->reset.latch = be16_to_cpu(config->reset.latch);
+               config->suspend.mode = be16_to_cpu(config->suspend.mode);
+               config->suspend.lowPower =
+                               be16_to_cpu(config->suspend.lowPower);
+               config->suspend.latch = be16_to_cpu(config->suspend.latch);
+
+               /* apparently not implemented yet */
+               config->reset.lowPower = 0;
+               config->suspend.lowPower = 0;
+
+               return 0;
+       } else if (ret >= 0)
+               return -1;
+       else
+               return ret;
+
+}
+
+/*
+ * cp210x_get_config
+ * Reads from the CP210x 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 cp210x_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;
+       }
+
+       /* Issue the request, attempting to read 'size' bytes */
+       result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
+                               request,
+                               USB_DIR_IN|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
+                               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;
+}
+
+/*
+ * cp210x_set_config
+ * Writes to the CP210x configuration registers
+ * Values less than 16 bits wide are sent directly
+ * 'size' is specified in bytes.
+ */
+static int cp210x_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,
+                               USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 0x0000,
+                               0, buf, size, 300);
+       } else {
+               result = usb_control_msg(serial->dev,
+                               usb_sndctrlpipe(serial->dev, 0), request,
+                               USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 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;
+       }
+
+       return 0;
+}
+
+/*
+ * cp210x_set_config_single
+ * Convenience function for calling cp210x_set_config on single data values
+ * without requiring an integer pointer
+ */
+static inline int cp210x_set_config_single(struct usb_serial_port *port,
+               u8 request, unsigned int data)
+{
+       return cp210x_set_config(port, request, &data, 2);
+}
+
+/*
+ * cp210x_quantise_baudrate
+ * Quantises the baud rate as per AN205 Table 1
+ */
+static unsigned int cp210x_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 cp210x_open(struct tty_struct *tty, struct usb_serial_port *port)
+{
+       int result;
+
+       dbg("%s - port %d", __func__, port->number);
+
+       if (cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_ENABLE)) {
+               dev_err(&port->dev, "%s - Unable to enable UART\n",
+                               __func__);
+               return -EPROTO;
+       }
+
+       result = usb_serial_generic_open(tty, port);
+       if (result)
+               return result;
+
+       /* Configure the termios structure */
+       cp210x_get_termios(tty, port);
+       return 0;
+}
+
+static void cp210x_close(struct usb_serial_port *port)
+{
+       dbg("%s - port %d", __func__, port->number);
+
+       usb_serial_generic_close(port);
+
+       mutex_lock(&port->serial->disc_mutex);
+       if (!port->serial->disconnected)
+               cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);
+       mutex_unlock(&port->serial->disc_mutex);
+}
+
+static int cp210x_ioctl(struct tty_struct *tty, struct file *file,
+               unsigned int cmd, unsigned long arg)
+{
+       struct usb_serial_port *port = tty->driver_data;
+
+       dbg("%s (%d) cmd = 0x%04x", __func__, port->number, cmd);
+
+       switch (cmd) {
+
+       case TIOCMGET:
+       {
+               int result = cp210x_tiocmget(tty, file);
+               if (copy_to_user((int __user *)&arg, &result, sizeof(int)))
+                       return -EFAULT;
+               return 0;
+       }
+       break;
+
+       case TIOCMSET:
+       case TIOCMBIS:
+       case TIOCMBIC:
+       {
+               int val = 0;
+
+               if (copy_from_user(&val, (int __user *)&arg, sizeof(int)))
+                       return -EFAULT;
+
+               /* this looks wrong: TIOCMSET isn't going to work right */
+               if (cp210x_tiocmset(tty, file, (cmd == TIOCMBIC) ? 0 : val,
+                                       (cmd == TIOCMBIC) ? val : 0))
+                       return -EFAULT;
+               return 0;
+       }
+       break;
+
+       case CP210x_IOCTL_GPIOGET:
+       if (cp210x_get_partnum(port) == CP210x_PART_CP2103) {
+               u8 gpio = 0;
+               if (!cp210x_gpioget(port, &gpio) && !copy_to_user(
+                                       (__u8 __user *)arg, &gpio,
+                                       sizeof(gpio)))
+                       return 0;
+       }
+       return -EFAULT;
+       break;
+
+       case CP210x_IOCTL_GPIOSET:
+       if (cp210x_get_partnum(port) == CP210x_PART_CP2103 &&
+                       !cp210x_gpioset(port, arg))
+               return 0;
+       return -EFAULT;
+       break;
+
+       case CP210x_IOCTL_GPIOBIC:
+       case CP210x_IOCTL_GPIOBIS:
+       if (cp210x_get_partnum(port) == CP210x_PART_CP2103 &&
+                       !cp210x_gpiosetb(port,
+                               (cmd == CP210x_IOCTL_GPIOBIC) ?  0 : arg,
+                               (cmd == CP210x_IOCTL_GPIOBIC) ? arg : 0))
+               return 0;
+       return -EFAULT;
+       break;
+
+       case CP210x_IOCTL_DEVICERESET:
+       return cp210x_reset(port);
+       break;
+
+       case CP210x_IOCTL_PORTCONFGET:
+       {
+               struct cp210x_port_config config;
+               if (!cp210x_portconfget(port, &config) && !copy_to_user(
+                                       (struct cp210x_port_config __user *)arg,
+                                       &config, sizeof(config)))
+                       return 0;
+       }
+       return -EFAULT;
+       break;
+
+       case CP210x_IOCTL_PORTCONFSET:
+       {
+       struct cp210x_port_config config;
+       if (!copy_from_user(&config, (struct cp210x_port_config __user *)arg,
+                       sizeof(config)) &&
+                       !cp210x_portconfset(port, &config))
+               return 0;
+       return -EFAULT;
+       }
+       break;
+
+       case CP210x_IOCTL_SETVID:
+       {
+               unsigned int vid;
+               if (!copy_from_user(&vid, (unsigned int __user *)arg,
+                               sizeof(unsigned int)) &&
+                               !cp210x_setu16(port, 0x01, vid))
+                       return 0;
+               return -EFAULT;
+       }
+       break;
+
+       case CP210x_IOCTL_SETPID:
+       {
+               unsigned int pid;
+               if (!copy_from_user(&pid, (unsigned int __user *)arg,
+                               sizeof(unsigned int)) &&
+                               !cp210x_setu16(port, 0x02, pid))
+                       return 0;
+               return -EFAULT;
+       }
+       break;
+
+       case CP210x_IOCTL_SETPRODUCT:
+       {
+               __le16 usbstr[CP210x_MAX_PRODUCT_STRLEN + 1];
+               size_t len = cp210x_usbstr_from_user(usbstr,
+                               (struct cp210x_buffer __user *)arg,
+                               sizeof(usbstr));
+               if (len > 0 && cp210x_setstr(port, 0x03, usbstr) == len)
+                       return 0;
+               return -EFAULT;
+       }
+       break;
+
+       case CP210x_IOCTL_SETSERIAL:
+       {
+               __le16 usbstr[CP210x_MAX_SERIAL_STRLEN + 1];
+               size_t len = cp210x_usbstr_from_user(usbstr,
+                               (struct cp210x_buffer __user *)arg,
+                               sizeof(usbstr));
+               if (len > 0 && cp210x_setstr(port, 0x04, usbstr) == len)
+                       return 0;
+               return -EFAULT;
+       }
+       break;
+
+       case CP210x_IOCTL_SETDEVVER:
+       {
+               unsigned int ver;
+               if (!copy_from_user(&ver, (unsigned int __user *)arg,
+                               sizeof(unsigned int)) &&
+                               !cp210x_setu16(port, 0x07, ver))
+                       return 0;
+               return -EFAULT;
+       }
+       break;
+
+       default:
+       dbg("%s not supported = 0x%04x", __func__, cmd);
+       break;
+       }
+
+       return -ENOIOCTLCMD;
+}
+
+/*
+ * cp210x_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 cp210x_get_termios(struct tty_struct *tty,
+       struct usb_serial_port *port)
+{
+       unsigned int baud;
+
+       if (tty) {
+               cp210x_get_termios_port(tty->driver_data,
+                       &tty->termios->c_cflag, &baud);
+               tty_encode_baud_rate(tty, baud, baud);
+       }
+
+       else {
+               unsigned int cflag;
+               cflag = 0;
+               cp210x_get_termios_port(port, &cflag, &baud);
+       }
+}
+
+/*
+ * cp210x_get_termios_port
+ * This is the heart of cp210x_get_termios which always uses a &usb_serial_port.
+ */
+static void cp210x_get_termios_port(struct usb_serial_port *port,
+       unsigned int *cflagp, unsigned int *baudp)
+{
+       unsigned int cflag, modem_ctl[4];
+       unsigned int baud;
+       unsigned int bits;
+
+       dbg("%s - port %d", __func__, port->number);
+
+       cp210x_get_config(port, CP210X_GET_BAUDDIV, &baud, 2);
+       /* Convert to baudrate */
+       if (baud)
+               baud = cp210x_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud);
+
+       dbg("%s - baud rate = %d", __func__, baud);
+       *baudp = baud;
+
+       cflag = *cflagp;
+
+       cp210x_get_config(port, CP210X_GET_LINE_CTL, &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;
+               cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
+               break;
+       default:
+               dbg("%s - Unknown number of data bits, using 8", __func__);
+               cflag |= CS8;
+               bits &= ~BITS_DATA_MASK;
+               bits |= BITS_DATA_8;
+               cp210x_set_config(port, CP210X_SET_LINE_CTL, &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;
+               cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
+               break;
+       case BITS_PARITY_SPACE:
+               dbg("%s - parity = SPACE (not supported, disabling parity)",
+                               __func__);
+               cflag &= ~PARENB;
+               bits &= ~BITS_PARITY_MASK;
+               cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
+               break;
+       default:
+               dbg("%s - Unknown parity mode, disabling parity", __func__);
+               cflag &= ~PARENB;
+               bits &= ~BITS_PARITY_MASK;
+               cp210x_set_config(port, CP210X_SET_LINE_CTL, &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;
+               cp210x_set_config(port, CP210X_SET_LINE_CTL, &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;
+               cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);
+               break;
+       }
+
+       cp210x_get_config(port, CP210X_GET_FLOW, 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;
+       }
+
+       *cflagp = cflag;
+}
+
+static void cp210x_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 = cp210x_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 (cp210x_set_config_single(port, CP210X_SET_BAUDDIV,
+                                       ((BAUD_RATE_GEN_FREQ + baud/2) / baud))) {
+                       dbg("Baud rate requested not supported by device");
+                       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)) {
+               cp210x_get_config(port, CP210X_GET_LINE_CTL, &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("cp210x driver does not "
+                                       "support the number of bits requested,"
+                                       " using 8 bit mode\n");
+                               bits |= BITS_DATA_8;
+                               break;
+               }
+               if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
+                       dbg("Number of data bits requested "
+                                       "not supported by device\n");
+       }
+
+       if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
+               cp210x_get_config(port, CP210X_GET_LINE_CTL, &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 (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
+                       dbg("Parity mode not supported "
+                                       "by device\n");
+       }
+
+       if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
+               cp210x_get_config(port, CP210X_GET_LINE_CTL, &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 (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))
+                       dbg("Number of stop bits requested "
+                                       "not supported by device\n");
+       }
+
+       if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
+               cp210x_get_config(port, CP210X_GET_FLOW, 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]);
+               cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);
+       }
+
+}
+
+static int cp210x_tiocmset (struct tty_struct *tty, struct file *file,
+               unsigned int set, unsigned int clear)
+{
+       struct usb_serial_port *port = tty->driver_data;
+       return cp210x_tiocmset_port(port, file, set, clear);
+}
+
+static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *file,
+               unsigned int set, unsigned int clear)
+{
+       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 cp210x_set_config(port, CP210X_SET_MHS, &control, 2);
+}
+
+static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
+{
+       if (on)
+               cp210x_tiocmset_port(p, NULL,  TIOCM_DTR|TIOCM_RTS, 0);
+       else
+               cp210x_tiocmset_port(p, NULL,  0, TIOCM_DTR|TIOCM_RTS);
+}
+
+static int cp210x_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);
+
+       cp210x_get_config(port, CP210X_GET_MDMSTS, &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 int cp210x_carrier_raised(struct usb_serial_port *p)
+{
+       unsigned int control;
+       cp210x_get_config(p, CP210X_GET_MDMSTS, &control, 1);
+       if (control & CONTROL_DCD)
+               return 1;
+       return 0;
+}
+
+static void cp210x_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");
+       cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);
+}
+
+static int cp210x_startup(struct usb_serial *serial)
+{
+       /* cp210x buffers behave strangely unless device is reset */
+       usb_reset_device(serial->dev);
+       return 0;
+}
+
+static int __init cp210x_init(void)
+{
+       int retval;
+
+       retval = usb_serial_register(&cp210x_device);
+       if (retval)
+               return retval; /* Failed to register */
+
+       retval = usb_register(&cp210x_driver);
+       if (retval) {
+               /* Failed to register */
+               usb_serial_deregister(&cp210x_device);
+               return retval;
+       }
+
+       /* Success */
+       printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
+              DRIVER_DESC "\n");
+       return 0;
+}
+
+static void __exit cp210x_exit(void)
+{
+       usb_deregister(&cp210x_driver);
+       usb_serial_deregister(&cp210x_device);
+}
+
+module_init(cp210x_init);
+module_exit(cp210x_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");