diff options
Diffstat (limited to 'drivers/usb/serial/mct_u232.c')
| -rw-r--r-- | drivers/usb/serial/mct_u232.c | 778 |
1 files changed, 778 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..7887c312d --- /dev/null +++ b/drivers/usb/serial/mct_u232.c @@ -0,0 +1,778 @@ +// 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 int 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, struct ktermios *old); +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 int mct_u232_port_remove(struct usb_serial_port *port) +{ + struct mct_u232_private *priv; + + priv = usb_get_serial_port_data(port); + kfree(priv); + + return 0; +} + +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, + 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"); |