summaryrefslogtreecommitdiffstats
path: root/drivers/usb/serial/mct_u232.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/serial/mct_u232.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/serial/mct_u232.c')
-rw-r--r--drivers/usb/serial/mct_u232.c777
1 files changed, 777 insertions, 0 deletions
diff --git a/drivers/usb/serial/mct_u232.c b/drivers/usb/serial/mct_u232.c
new file mode 100644
index 000000000..d3852feb8
--- /dev/null
+++ b/drivers/usb/serial/mct_u232.c
@@ -0,0 +1,777 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * MCT (Magic Control Technology Corp.) USB RS232 Converter Driver
+ *
+ * Copyright (C) 2000 Wolfgang Grandegger (wolfgang@ces.ch)
+ *
+ * This program is largely derived from the Belkin USB Serial Adapter Driver
+ * (see belkin_sa.[ch]). All of the information about the device was acquired
+ * by using SniffUSB on Windows98. For technical details see mct_u232.h.
+ *
+ * William G. Greathouse and Greg Kroah-Hartman provided great help on how to
+ * do the reverse engineering and how to write a USB serial device driver.
+ *
+ * TO BE DONE, TO BE CHECKED:
+ * DTR/RTS signal handling may be incomplete or incorrect. I have mainly
+ * implemented what I have seen with SniffUSB or found in belkin_sa.c.
+ * For further TODOs check also belkin_sa.c.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+#include <asm/unaligned.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+#include <linux/serial.h>
+#include "mct_u232.h"
+
+#define DRIVER_AUTHOR "Wolfgang Grandegger <wolfgang@ces.ch>"
+#define DRIVER_DESC "Magic Control Technology USB-RS232 converter driver"
+
+/*
+ * Function prototypes
+ */
+static int mct_u232_port_probe(struct usb_serial_port *port);
+static void mct_u232_port_remove(struct usb_serial_port *remove);
+static int mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port);
+static void mct_u232_close(struct usb_serial_port *port);
+static void mct_u232_dtr_rts(struct usb_serial_port *port, int on);
+static void mct_u232_read_int_callback(struct urb *urb);
+static void mct_u232_set_termios(struct tty_struct *tty,
+ struct usb_serial_port *port,
+ const struct ktermios *old_termios);
+static void mct_u232_break_ctl(struct tty_struct *tty, int break_state);
+static int mct_u232_tiocmget(struct tty_struct *tty);
+static int mct_u232_tiocmset(struct tty_struct *tty,
+ unsigned int set, unsigned int clear);
+static void mct_u232_throttle(struct tty_struct *tty);
+static void mct_u232_unthrottle(struct tty_struct *tty);
+
+
+/*
+ * All of the device info needed for the MCT USB-RS232 converter.
+ */
+static const struct usb_device_id id_table[] = {
+ { USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
+ { USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
+ { USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
+ { USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
+ { } /* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, id_table);
+
+static struct usb_serial_driver mct_u232_device = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "mct_u232",
+ },
+ .description = "MCT U232",
+ .id_table = id_table,
+ .num_ports = 1,
+ .open = mct_u232_open,
+ .close = mct_u232_close,
+ .dtr_rts = mct_u232_dtr_rts,
+ .throttle = mct_u232_throttle,
+ .unthrottle = mct_u232_unthrottle,
+ .read_int_callback = mct_u232_read_int_callback,
+ .set_termios = mct_u232_set_termios,
+ .break_ctl = mct_u232_break_ctl,
+ .tiocmget = mct_u232_tiocmget,
+ .tiocmset = mct_u232_tiocmset,
+ .tiocmiwait = usb_serial_generic_tiocmiwait,
+ .port_probe = mct_u232_port_probe,
+ .port_remove = mct_u232_port_remove,
+ .get_icount = usb_serial_generic_get_icount,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+ &mct_u232_device, NULL
+};
+
+struct mct_u232_private {
+ struct urb *read_urb;
+ spinlock_t lock;
+ unsigned int control_state; /* Modem Line Setting (TIOCM) */
+ unsigned char last_lcr; /* Line Control Register */
+ unsigned char last_lsr; /* Line Status Register */
+ unsigned char last_msr; /* Modem Status Register */
+ unsigned int rx_flags; /* Throttling flags */
+};
+
+#define THROTTLED 0x01
+
+/*
+ * Handle vendor specific USB requests
+ */
+
+#define WDR_TIMEOUT 5000 /* default urb timeout */
+
+/*
+ * Later day 2.6.0-test kernels have new baud rates like B230400 which
+ * we do not know how to support. We ignore them for the moment.
+ */
+static int mct_u232_calculate_baud_rate(struct usb_serial *serial,
+ speed_t value, speed_t *result)
+{
+ *result = value;
+
+ if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID
+ || le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_BELKIN_F5U109_PID) {
+ switch (value) {
+ case 300:
+ return 0x01;
+ case 600:
+ return 0x02; /* this one not tested */
+ case 1200:
+ return 0x03;
+ case 2400:
+ return 0x04;
+ case 4800:
+ return 0x06;
+ case 9600:
+ return 0x08;
+ case 19200:
+ return 0x09;
+ case 38400:
+ return 0x0a;
+ case 57600:
+ return 0x0b;
+ case 115200:
+ return 0x0c;
+ default:
+ *result = 9600;
+ return 0x08;
+ }
+ } else {
+ /* FIXME: Can we use any divider - should we do
+ divider = 115200/value;
+ real baud = 115200/divider */
+ switch (value) {
+ case 300: break;
+ case 600: break;
+ case 1200: break;
+ case 2400: break;
+ case 4800: break;
+ case 9600: break;
+ case 19200: break;
+ case 38400: break;
+ case 57600: break;
+ case 115200: break;
+ default:
+ value = 9600;
+ *result = 9600;
+ }
+ return 115200/value;
+ }
+}
+
+static int mct_u232_set_baud_rate(struct tty_struct *tty,
+ struct usb_serial *serial, struct usb_serial_port *port, speed_t value)
+{
+ unsigned int divisor;
+ int rc;
+ unsigned char *buf;
+ unsigned char cts_enable_byte = 0;
+ speed_t speed;
+
+ buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
+ if (buf == NULL)
+ return -ENOMEM;
+
+ divisor = mct_u232_calculate_baud_rate(serial, value, &speed);
+ put_unaligned_le32(divisor, buf);
+ rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+ MCT_U232_SET_BAUD_RATE_REQUEST,
+ MCT_U232_SET_REQUEST_TYPE,
+ 0, 0, buf, MCT_U232_SET_BAUD_RATE_SIZE,
+ WDR_TIMEOUT);
+ if (rc < 0) /*FIXME: What value speed results */
+ dev_err(&port->dev, "Set BAUD RATE %d failed (error = %d)\n",
+ value, rc);
+ else
+ tty_encode_baud_rate(tty, speed, speed);
+ dev_dbg(&port->dev, "set_baud_rate: value: 0x%x, divisor: 0x%x\n", value, divisor);
+
+ /* Mimic the MCT-supplied Windows driver (version 1.21P.0104), which
+ always sends two extra USB 'device request' messages after the
+ 'baud rate change' message. The actual functionality of the
+ request codes in these messages is not fully understood but these
+ particular codes are never seen in any operation besides a baud
+ rate change. Both of these messages send a single byte of data.
+ In the first message, the value of this byte is always zero.
+
+ The second message has been determined experimentally to control
+ whether data will be transmitted to a device which is not asserting
+ the 'CTS' signal. If the second message's data byte is zero, data
+ will be transmitted even if 'CTS' is not asserted (i.e. no hardware
+ flow control). if the second message's data byte is nonzero (a
+ value of 1 is used by this driver), data will not be transmitted to
+ a device which is not asserting 'CTS'.
+ */
+
+ buf[0] = 0;
+ rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+ MCT_U232_SET_UNKNOWN1_REQUEST,
+ MCT_U232_SET_REQUEST_TYPE,
+ 0, 0, buf, MCT_U232_SET_UNKNOWN1_SIZE,
+ WDR_TIMEOUT);
+ if (rc < 0)
+ dev_err(&port->dev, "Sending USB device request code %d "
+ "failed (error = %d)\n", MCT_U232_SET_UNKNOWN1_REQUEST,
+ rc);
+
+ if (port && C_CRTSCTS(tty))
+ cts_enable_byte = 1;
+
+ dev_dbg(&port->dev, "set_baud_rate: send second control message, data = %02X\n",
+ cts_enable_byte);
+ buf[0] = cts_enable_byte;
+ rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+ MCT_U232_SET_CTS_REQUEST,
+ MCT_U232_SET_REQUEST_TYPE,
+ 0, 0, buf, MCT_U232_SET_CTS_SIZE,
+ WDR_TIMEOUT);
+ if (rc < 0)
+ dev_err(&port->dev, "Sending USB device request code %d "
+ "failed (error = %d)\n", MCT_U232_SET_CTS_REQUEST, rc);
+
+ kfree(buf);
+ return rc;
+} /* mct_u232_set_baud_rate */
+
+static int mct_u232_set_line_ctrl(struct usb_serial_port *port,
+ unsigned char lcr)
+{
+ int rc;
+ unsigned char *buf;
+
+ buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
+ if (buf == NULL)
+ return -ENOMEM;
+
+ buf[0] = lcr;
+ rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
+ MCT_U232_SET_LINE_CTRL_REQUEST,
+ MCT_U232_SET_REQUEST_TYPE,
+ 0, 0, buf, MCT_U232_SET_LINE_CTRL_SIZE,
+ WDR_TIMEOUT);
+ if (rc < 0)
+ dev_err(&port->dev, "Set LINE CTRL 0x%x failed (error = %d)\n", lcr, rc);
+ dev_dbg(&port->dev, "set_line_ctrl: 0x%x\n", lcr);
+ kfree(buf);
+ return rc;
+} /* mct_u232_set_line_ctrl */
+
+static int mct_u232_set_modem_ctrl(struct usb_serial_port *port,
+ unsigned int control_state)
+{
+ int rc;
+ unsigned char mcr;
+ unsigned char *buf;
+
+ buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
+ if (buf == NULL)
+ return -ENOMEM;
+
+ mcr = MCT_U232_MCR_NONE;
+ if (control_state & TIOCM_DTR)
+ mcr |= MCT_U232_MCR_DTR;
+ if (control_state & TIOCM_RTS)
+ mcr |= MCT_U232_MCR_RTS;
+
+ buf[0] = mcr;
+ rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
+ MCT_U232_SET_MODEM_CTRL_REQUEST,
+ MCT_U232_SET_REQUEST_TYPE,
+ 0, 0, buf, MCT_U232_SET_MODEM_CTRL_SIZE,
+ WDR_TIMEOUT);
+ kfree(buf);
+
+ dev_dbg(&port->dev, "set_modem_ctrl: state=0x%x ==> mcr=0x%x\n", control_state, mcr);
+
+ if (rc < 0) {
+ dev_err(&port->dev, "Set MODEM CTRL 0x%x failed (error = %d)\n", mcr, rc);
+ return rc;
+ }
+ return 0;
+} /* mct_u232_set_modem_ctrl */
+
+static int mct_u232_get_modem_stat(struct usb_serial_port *port,
+ unsigned char *msr)
+{
+ int rc;
+ unsigned char *buf;
+
+ buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
+ if (buf == NULL) {
+ *msr = 0;
+ return -ENOMEM;
+ }
+ rc = usb_control_msg(port->serial->dev, usb_rcvctrlpipe(port->serial->dev, 0),
+ MCT_U232_GET_MODEM_STAT_REQUEST,
+ MCT_U232_GET_REQUEST_TYPE,
+ 0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
+ WDR_TIMEOUT);
+ if (rc < MCT_U232_GET_MODEM_STAT_SIZE) {
+ dev_err(&port->dev, "Get MODEM STATus failed (error = %d)\n", rc);
+
+ if (rc >= 0)
+ rc = -EIO;
+
+ *msr = 0;
+ } else {
+ *msr = buf[0];
+ }
+ dev_dbg(&port->dev, "get_modem_stat: 0x%x\n", *msr);
+ kfree(buf);
+ return rc;
+} /* mct_u232_get_modem_stat */
+
+static void mct_u232_msr_to_icount(struct async_icount *icount,
+ unsigned char msr)
+{
+ /* Translate Control Line states */
+ if (msr & MCT_U232_MSR_DDSR)
+ icount->dsr++;
+ if (msr & MCT_U232_MSR_DCTS)
+ icount->cts++;
+ if (msr & MCT_U232_MSR_DRI)
+ icount->rng++;
+ if (msr & MCT_U232_MSR_DCD)
+ icount->dcd++;
+} /* mct_u232_msr_to_icount */
+
+static void mct_u232_msr_to_state(struct usb_serial_port *port,
+ unsigned int *control_state, unsigned char msr)
+{
+ /* Translate Control Line states */
+ if (msr & MCT_U232_MSR_DSR)
+ *control_state |= TIOCM_DSR;
+ else
+ *control_state &= ~TIOCM_DSR;
+ if (msr & MCT_U232_MSR_CTS)
+ *control_state |= TIOCM_CTS;
+ else
+ *control_state &= ~TIOCM_CTS;
+ if (msr & MCT_U232_MSR_RI)
+ *control_state |= TIOCM_RI;
+ else
+ *control_state &= ~TIOCM_RI;
+ if (msr & MCT_U232_MSR_CD)
+ *control_state |= TIOCM_CD;
+ else
+ *control_state &= ~TIOCM_CD;
+ dev_dbg(&port->dev, "msr_to_state: msr=0x%x ==> state=0x%x\n", msr, *control_state);
+} /* mct_u232_msr_to_state */
+
+/*
+ * Driver's tty interface functions
+ */
+
+static int mct_u232_port_probe(struct usb_serial_port *port)
+{
+ struct usb_serial *serial = port->serial;
+ struct mct_u232_private *priv;
+
+ /* check first to simplify error handling */
+ if (!serial->port[1] || !serial->port[1]->interrupt_in_urb) {
+ dev_err(&port->dev, "expected endpoint missing\n");
+ return -ENODEV;
+ }
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ /* Use second interrupt-in endpoint for reading. */
+ priv->read_urb = serial->port[1]->interrupt_in_urb;
+ priv->read_urb->context = port;
+
+ spin_lock_init(&priv->lock);
+
+ usb_set_serial_port_data(port, priv);
+
+ return 0;
+}
+
+static void mct_u232_port_remove(struct usb_serial_port *port)
+{
+ struct mct_u232_private *priv;
+
+ priv = usb_get_serial_port_data(port);
+ kfree(priv);
+}
+
+static int mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port)
+{
+ struct usb_serial *serial = port->serial;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+ int retval = 0;
+ unsigned int control_state;
+ unsigned long flags;
+ unsigned char last_lcr;
+ unsigned char last_msr;
+
+ /* Compensate for a hardware bug: although the Sitecom U232-P25
+ * device reports a maximum output packet size of 32 bytes,
+ * it seems to be able to accept only 16 bytes (and that's what
+ * SniffUSB says too...)
+ */
+ if (le16_to_cpu(serial->dev->descriptor.idProduct)
+ == MCT_U232_SITECOM_PID)
+ port->bulk_out_size = 16;
+
+ /* Do a defined restart: the normal serial device seems to
+ * always turn on DTR and RTS here, so do the same. I'm not
+ * sure if this is really necessary. But it should not harm
+ * either.
+ */
+ spin_lock_irqsave(&priv->lock, flags);
+ if (tty && C_BAUD(tty))
+ priv->control_state = TIOCM_DTR | TIOCM_RTS;
+ else
+ priv->control_state = 0;
+
+ priv->last_lcr = (MCT_U232_DATA_BITS_8 |
+ MCT_U232_PARITY_NONE |
+ MCT_U232_STOP_BITS_1);
+ control_state = priv->control_state;
+ last_lcr = priv->last_lcr;
+ spin_unlock_irqrestore(&priv->lock, flags);
+ mct_u232_set_modem_ctrl(port, control_state);
+ mct_u232_set_line_ctrl(port, last_lcr);
+
+ /* Read modem status and update control state */
+ mct_u232_get_modem_stat(port, &last_msr);
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->last_msr = last_msr;
+ mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ retval = usb_submit_urb(priv->read_urb, GFP_KERNEL);
+ if (retval) {
+ dev_err(&port->dev,
+ "usb_submit_urb(read) failed pipe 0x%x err %d\n",
+ port->read_urb->pipe, retval);
+ goto error;
+ }
+
+ retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
+ if (retval) {
+ usb_kill_urb(priv->read_urb);
+ dev_err(&port->dev,
+ "usb_submit_urb(read int) failed pipe 0x%x err %d",
+ port->interrupt_in_urb->pipe, retval);
+ goto error;
+ }
+ return 0;
+
+error:
+ return retval;
+} /* mct_u232_open */
+
+static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
+{
+ unsigned int control_state;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+
+ spin_lock_irq(&priv->lock);
+ if (on)
+ priv->control_state |= TIOCM_DTR | TIOCM_RTS;
+ else
+ priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
+ control_state = priv->control_state;
+ spin_unlock_irq(&priv->lock);
+
+ mct_u232_set_modem_ctrl(port, control_state);
+}
+
+static void mct_u232_close(struct usb_serial_port *port)
+{
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+
+ usb_kill_urb(priv->read_urb);
+ usb_kill_urb(port->interrupt_in_urb);
+
+ usb_serial_generic_close(port);
+} /* mct_u232_close */
+
+
+static void mct_u232_read_int_callback(struct urb *urb)
+{
+ struct usb_serial_port *port = urb->context;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+ unsigned char *data = urb->transfer_buffer;
+ int retval;
+ int status = urb->status;
+ unsigned long flags;
+
+ switch (status) {
+ case 0:
+ /* success */
+ break;
+ case -ECONNRESET:
+ case -ENOENT:
+ case -ESHUTDOWN:
+ /* this urb is terminated, clean up */
+ dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
+ __func__, status);
+ return;
+ default:
+ dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
+ __func__, status);
+ goto exit;
+ }
+
+ usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
+
+ /*
+ * Work-a-round: handle the 'usual' bulk-in pipe here
+ */
+ if (urb->transfer_buffer_length > 2) {
+ if (urb->actual_length) {
+ tty_insert_flip_string(&port->port, data,
+ urb->actual_length);
+ tty_flip_buffer_push(&port->port);
+ }
+ goto exit;
+ }
+
+ /*
+ * The interrupt-in pipe signals exceptional conditions (modem line
+ * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
+ */
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->last_msr = data[MCT_U232_MSR_INDEX];
+
+ /* Record Control Line states */
+ mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
+
+ mct_u232_msr_to_icount(&port->icount, priv->last_msr);
+
+#if 0
+ /* Not yet handled. See belkin_sa.c for further information */
+ /* Now to report any errors */
+ priv->last_lsr = data[MCT_U232_LSR_INDEX];
+ /*
+ * fill in the flip buffer here, but I do not know the relation
+ * to the current/next receive buffer or characters. I need
+ * to look in to this before committing any code.
+ */
+ if (priv->last_lsr & MCT_U232_LSR_ERR) {
+ tty = tty_port_tty_get(&port->port);
+ /* Overrun Error */
+ if (priv->last_lsr & MCT_U232_LSR_OE) {
+ }
+ /* Parity Error */
+ if (priv->last_lsr & MCT_U232_LSR_PE) {
+ }
+ /* Framing Error */
+ if (priv->last_lsr & MCT_U232_LSR_FE) {
+ }
+ /* Break Indicator */
+ if (priv->last_lsr & MCT_U232_LSR_BI) {
+ }
+ tty_kref_put(tty);
+ }
+#endif
+ wake_up_interruptible(&port->port.delta_msr_wait);
+ spin_unlock_irqrestore(&priv->lock, flags);
+exit:
+ retval = usb_submit_urb(urb, GFP_ATOMIC);
+ if (retval)
+ dev_err(&port->dev,
+ "%s - usb_submit_urb failed with result %d\n",
+ __func__, retval);
+} /* mct_u232_read_int_callback */
+
+static void mct_u232_set_termios(struct tty_struct *tty,
+ struct usb_serial_port *port,
+ const struct ktermios *old_termios)
+{
+ struct usb_serial *serial = port->serial;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+ struct ktermios *termios = &tty->termios;
+ unsigned int cflag = termios->c_cflag;
+ unsigned int old_cflag = old_termios->c_cflag;
+ unsigned long flags;
+ unsigned int control_state;
+ unsigned char last_lcr;
+
+ /* get a local copy of the current port settings */
+ spin_lock_irqsave(&priv->lock, flags);
+ control_state = priv->control_state;
+ spin_unlock_irqrestore(&priv->lock, flags);
+ last_lcr = 0;
+
+ /*
+ * Update baud rate.
+ * Do not attempt to cache old rates and skip settings,
+ * disconnects screw such tricks up completely.
+ * Premature optimization is the root of all evil.
+ */
+
+ /* reassert DTR and RTS on transition from B0 */
+ if ((old_cflag & CBAUD) == B0) {
+ dev_dbg(&port->dev, "%s: baud was B0\n", __func__);
+ control_state |= TIOCM_DTR | TIOCM_RTS;
+ mct_u232_set_modem_ctrl(port, control_state);
+ }
+
+ mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
+
+ if ((cflag & CBAUD) == B0) {
+ dev_dbg(&port->dev, "%s: baud is B0\n", __func__);
+ /* Drop RTS and DTR */
+ control_state &= ~(TIOCM_DTR | TIOCM_RTS);
+ mct_u232_set_modem_ctrl(port, control_state);
+ }
+
+ /*
+ * Update line control register (LCR)
+ */
+
+ /* set the parity */
+ if (cflag & PARENB)
+ last_lcr |= (cflag & PARODD) ?
+ MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
+ else
+ last_lcr |= MCT_U232_PARITY_NONE;
+
+ /* set the number of data bits */
+ switch (cflag & CSIZE) {
+ case CS5:
+ last_lcr |= MCT_U232_DATA_BITS_5; break;
+ case CS6:
+ last_lcr |= MCT_U232_DATA_BITS_6; break;
+ case CS7:
+ last_lcr |= MCT_U232_DATA_BITS_7; break;
+ case CS8:
+ last_lcr |= MCT_U232_DATA_BITS_8; break;
+ default:
+ dev_err(&port->dev,
+ "CSIZE was not CS5-CS8, using default of 8\n");
+ last_lcr |= MCT_U232_DATA_BITS_8;
+ break;
+ }
+
+ termios->c_cflag &= ~CMSPAR;
+
+ /* set the number of stop bits */
+ last_lcr |= (cflag & CSTOPB) ?
+ MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
+
+ mct_u232_set_line_ctrl(port, last_lcr);
+
+ /* save off the modified port settings */
+ spin_lock_irqsave(&priv->lock, flags);
+ priv->control_state = control_state;
+ priv->last_lcr = last_lcr;
+ spin_unlock_irqrestore(&priv->lock, flags);
+} /* mct_u232_set_termios */
+
+static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
+{
+ struct usb_serial_port *port = tty->driver_data;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+ unsigned char lcr;
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ lcr = priv->last_lcr;
+
+ if (break_state)
+ lcr |= MCT_U232_SET_BREAK;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ mct_u232_set_line_ctrl(port, lcr);
+} /* mct_u232_break_ctl */
+
+
+static int mct_u232_tiocmget(struct tty_struct *tty)
+{
+ struct usb_serial_port *port = tty->driver_data;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+ unsigned int control_state;
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ control_state = priv->control_state;
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return control_state;
+}
+
+static int mct_u232_tiocmset(struct tty_struct *tty,
+ unsigned int set, unsigned int clear)
+{
+ struct usb_serial_port *port = tty->driver_data;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+ unsigned int control_state;
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->lock, flags);
+ control_state = priv->control_state;
+
+ if (set & TIOCM_RTS)
+ control_state |= TIOCM_RTS;
+ if (set & TIOCM_DTR)
+ control_state |= TIOCM_DTR;
+ if (clear & TIOCM_RTS)
+ control_state &= ~TIOCM_RTS;
+ if (clear & TIOCM_DTR)
+ control_state &= ~TIOCM_DTR;
+
+ priv->control_state = control_state;
+ spin_unlock_irqrestore(&priv->lock, flags);
+ return mct_u232_set_modem_ctrl(port, control_state);
+}
+
+static void mct_u232_throttle(struct tty_struct *tty)
+{
+ struct usb_serial_port *port = tty->driver_data;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+ unsigned int control_state;
+
+ spin_lock_irq(&priv->lock);
+ priv->rx_flags |= THROTTLED;
+ if (C_CRTSCTS(tty)) {
+ priv->control_state &= ~TIOCM_RTS;
+ control_state = priv->control_state;
+ spin_unlock_irq(&priv->lock);
+ mct_u232_set_modem_ctrl(port, control_state);
+ } else {
+ spin_unlock_irq(&priv->lock);
+ }
+}
+
+static void mct_u232_unthrottle(struct tty_struct *tty)
+{
+ struct usb_serial_port *port = tty->driver_data;
+ struct mct_u232_private *priv = usb_get_serial_port_data(port);
+ unsigned int control_state;
+
+ spin_lock_irq(&priv->lock);
+ if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
+ priv->rx_flags &= ~THROTTLED;
+ priv->control_state |= TIOCM_RTS;
+ control_state = priv->control_state;
+ spin_unlock_irq(&priv->lock);
+ mct_u232_set_modem_ctrl(port, control_state);
+ } else {
+ spin_unlock_irq(&priv->lock);
+ }
+}
+
+module_usb_serial_driver(serial_drivers, id_table);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");