tty: usb-serial krefs

[linux-2.6/mini2440.git] / drivers / usb / serial / belkin_sa.c

/*
 * Belkin USB Serial Adapter Driver
 *
 *  Copyright (C) 2000          William Greathouse (wgreathouse@smva.com)
 *  Copyright (C) 2000-2001     Greg Kroah-Hartman (greg@kroah.com)
 *
 *  This program is largely derived from work by the linux-usb group
 *  and associated source files.  Please see the usb/serial files for
 *  individual credits and copyrights.
 *
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2 of the License, or
 *      (at your option) any later version.
 *
 * See Documentation/usb/usb-serial.txt for more information on using this
 * driver
 *
 * TODO:
 * -- Add true modem contol line query capability.  Currently we track the
 *    states reported by the interrupt and the states we request.
 * -- Add error reporting back to application for UART error conditions.
 *    Just point me at how to implement this and I'll do it. I've put the
 *    framework in, but haven't analyzed the "tty_flip" interface yet.
 * -- Add support for flush commands
 * -- Add everything that is missing :)
 *
 * 27-Nov-2001 gkh
 *      compressed all the differnent device entries into 1.
 *
 * 30-May-2001 gkh
 *      switched from using spinlock to a semaphore, which fixes lots of
 *      problems.
 *
 * 08-Apr-2001 gb
 *      - Identify version on module load.
 *
 * 12-Mar-2001 gkh
 *      - Added support for the GoHubs GO-COM232 device which is the same as the
 *        Peracom device.
 *
 * 06-Nov-2000 gkh
 *      - Added support for the old Belkin and Peracom devices.
 *      - Made the port able to be opened multiple times.
 *      - Added some defaults incase the line settings are things these devices
 *        can't support.
 *
 * 18-Oct-2000 William Greathouse
 *    Released into the wild (linux-usb-devel)
 *
 * 17-Oct-2000 William Greathouse
 *    Add code to recognize firmware version and set hardware flow control
 *    appropriately.  Belkin states that firmware prior to 3.05 does not
 *    operate correctly in hardware handshake mode.  I have verified this
 *    on firmware 2.05 -- for both RTS and DTR input flow control, the control
 *    line is not reset.  The test performed by the Belkin Win* driver is
 *    to enable hardware flow control for firmware 2.06 or greater and
 *    for 1.00 or prior.  I am only enabling for 2.06 or greater.
 *
 * 12-Oct-2000 William Greathouse
 *    First cut at supporting Belkin USB Serial Adapter F5U103
 *    I did not have a copy of the original work to support this
 *    adapter, so pardon any stupid mistakes.  All of the information
 *    I am using to write this driver was acquired by using a modified
 *    UsbSnoop on Windows2000 and from examining the other USB drivers.
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "belkin_sa.h"

static int debug;

/*
 * Version Information
 */
#define DRIVER_VERSION "v1.2"
#define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
#define DRIVER_DESC "USB Belkin Serial converter driver"

/* function prototypes for a Belkin USB Serial Adapter F5U103 */
static int  belkin_sa_startup(struct usb_serial *serial);
static void belkin_sa_shutdown(struct usb_serial *serial);
static int  belkin_sa_open(struct tty_struct *tty,
                        struct usb_serial_port *port, struct file *filp);
static void belkin_sa_close(struct tty_struct *tty,
                        struct usb_serial_port *port, struct file *filp);
static void belkin_sa_read_int_callback(struct urb *urb);
static void belkin_sa_set_termios(struct tty_struct *tty,
                        struct usb_serial_port *port, struct ktermios * old);
static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state);
static int  belkin_sa_tiocmget(struct tty_struct *tty, struct file *file);
static int  belkin_sa_tiocmset(struct tty_struct *tty, struct file *file,
                                        unsigned int set, unsigned int clear);


static struct usb_device_id id_table_combined [] = {
        { USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
        { USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
        { USB_DEVICE(PERACOM_VID, PERACOM_PID) },
        { USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
        { USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
        { USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
        { }     /* Terminating entry */
};

MODULE_DEVICE_TABLE(usb, id_table_combined);

static struct usb_driver belkin_driver = {
        .name =         "belkin",
        .probe =        usb_serial_probe,
        .disconnect =   usb_serial_disconnect,
        .id_table =     id_table_combined,
        .no_dynamic_id =        1,
};

/* All of the device info needed for the serial converters */
static struct usb_serial_driver belkin_device = {
        .driver = {
                .owner =        THIS_MODULE,
                .name =         "belkin",
        },
        .description =          "Belkin / Peracom / GoHubs USB Serial Adapter",
        .usb_driver =           &belkin_driver,
        .id_table =             id_table_combined,
        .num_ports =            1,
        .open =                 belkin_sa_open,
        .close =                belkin_sa_close,
        .read_int_callback =    belkin_sa_read_int_callback,
                                        /* How we get the status info */
        .set_termios =          belkin_sa_set_termios,
        .break_ctl =            belkin_sa_break_ctl,
        .tiocmget =             belkin_sa_tiocmget,
        .tiocmset =             belkin_sa_tiocmset,
        .attach =               belkin_sa_startup,
        .shutdown =             belkin_sa_shutdown,
};


struct belkin_sa_private {
        spinlock_t              lock;
        unsigned long           control_state;
        unsigned char           last_lsr;
        unsigned char           last_msr;
        int                     bad_flow_control;
};


/*
 * ***************************************************************************
 * Belkin USB Serial Adapter F5U103 specific driver functions
 * ***************************************************************************
 */

#define WDR_TIMEOUT 5000 /* default urb timeout */

/* assumes that struct usb_serial *serial is available */
#define BSA_USB_CMD(c, v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
                                            (c), BELKIN_SA_SET_REQUEST_TYPE, \
                                            (v), 0, NULL, 0, WDR_TIMEOUT)

/* do some startup allocations not currently performed by usb_serial_probe() */
static int belkin_sa_startup(struct usb_serial *serial)
{
        struct usb_device *dev = serial->dev;
        struct belkin_sa_private *priv;

        /* allocate the private data structure */
        priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
        if (!priv)
                return -1; /* error */
        /* set initial values for control structures */
        spin_lock_init(&priv->lock);
        priv->control_state = 0;
        priv->last_lsr = 0;
        priv->last_msr = 0;
        /* see comments at top of file */
        priv->bad_flow_control =
                (le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
        info("bcdDevice: %04x, bfc: %d",
                                        le16_to_cpu(dev->descriptor.bcdDevice),
                                        priv->bad_flow_control);

        init_waitqueue_head(&serial->port[0]->write_wait);
        usb_set_serial_port_data(serial->port[0], priv);

        return 0;
}


static void belkin_sa_shutdown(struct usb_serial *serial)
{
        struct belkin_sa_private *priv;
        int i;

        dbg("%s", __func__);

        /* stop reads and writes on all ports */
        for (i = 0; i < serial->num_ports; ++i) {
                /* My special items, the standard routines free my urbs */
                priv = usb_get_serial_port_data(serial->port[i]);
                kfree(priv);
        }
}


static int  belkin_sa_open(struct tty_struct *tty,
                        struct usb_serial_port *port, struct file *filp)
{
        int retval = 0;

        dbg("%s port %d", __func__, port->number);

        /*Start reading from the device*/
        /* TODO: Look at possibility of submitting multiple URBs to device to
         *       enhance buffering.  Win trace shows 16 initial read URBs.
         */
        port->read_urb->dev = port->serial->dev;
        retval = usb_submit_urb(port->read_urb, GFP_KERNEL);
        if (retval) {
                err("usb_submit_urb(read bulk) failed");
                goto exit;
        }

        port->interrupt_in_urb->dev = port->serial->dev;
        retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
        if (retval) {
                usb_kill_urb(port->read_urb);
                err(" usb_submit_urb(read int) failed");
        }

exit:
        return retval;
} /* belkin_sa_open */


static void belkin_sa_close(struct tty_struct *tty,
                        struct usb_serial_port *port, struct file *filp)
{
        dbg("%s port %d", __func__, port->number);

        /* shutdown our bulk reads and writes */
        usb_kill_urb(port->write_urb);
        usb_kill_urb(port->read_urb);
        usb_kill_urb(port->interrupt_in_urb);
} /* belkin_sa_close */


static void belkin_sa_read_int_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        struct belkin_sa_private *priv;
        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 */
                dbg("%s - urb shutting down with status: %d",
                    __func__, status);
                return;
        default:
                dbg("%s - nonzero urb status received: %d",
                    __func__, status);
                goto exit;
        }

        usb_serial_debug_data(debug, &port->dev, __func__,
                                        urb->actual_length, data);

        /* Handle known interrupt data */
        /* ignore data[0] and data[1] */

        priv = usb_get_serial_port_data(port);
        spin_lock_irqsave(&priv->lock, flags);
        priv->last_msr = data[BELKIN_SA_MSR_INDEX];

        /* Record Control Line states */
        if (priv->last_msr & BELKIN_SA_MSR_DSR)
                priv->control_state |= TIOCM_DSR;
        else
                priv->control_state &= ~TIOCM_DSR;

        if (priv->last_msr & BELKIN_SA_MSR_CTS)
                priv->control_state |= TIOCM_CTS;
        else
                priv->control_state &= ~TIOCM_CTS;

        if (priv->last_msr & BELKIN_SA_MSR_RI)
                priv->control_state |= TIOCM_RI;
        else
                priv->control_state &= ~TIOCM_RI;

        if (priv->last_msr & BELKIN_SA_MSR_CD)
                priv->control_state |= TIOCM_CD;
        else
                priv->control_state &= ~TIOCM_CD;

        /* Now to report any errors */
        priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
#if 0
        /*
         * 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 & BELKIN_SA_LSR_ERR) {
                tty = tty_port_tty_get(&port->port);
                /* Overrun Error */
                if (priv->last_lsr & BELKIN_SA_LSR_OE) {
                }
                /* Parity Error */
                if (priv->last_lsr & BELKIN_SA_LSR_PE) {
                }
                /* Framing Error */
                if (priv->last_lsr & BELKIN_SA_LSR_FE) {
                }
                /* Break Indicator */
                if (priv->last_lsr & BELKIN_SA_LSR_BI) {
                }
                tty_kref_put(tty);
        }
#endif
        spin_unlock_irqrestore(&priv->lock, flags);
exit:
        retval = usb_submit_urb(urb, GFP_ATOMIC);
        if (retval)
                err("%s - usb_submit_urb failed with result %d",
                     __func__, retval);
}

static void belkin_sa_set_termios(struct tty_struct *tty,
                struct usb_serial_port *port, struct ktermios *old_termios)
{
        struct usb_serial *serial = port->serial;
        struct belkin_sa_private *priv = usb_get_serial_port_data(port);
        unsigned int iflag;
        unsigned int cflag;
        unsigned int old_iflag = 0;
        unsigned int old_cflag = 0;
        __u16 urb_value = 0; /* Will hold the new flags */
        unsigned long flags;
        unsigned long control_state;
        int bad_flow_control;
        speed_t baud;
        struct ktermios *termios = tty->termios;

        iflag = termios->c_iflag;
        cflag = termios->c_cflag;

        termios->c_cflag &= ~CMSPAR;

        /* get a local copy of the current port settings */
        spin_lock_irqsave(&priv->lock, flags);
        control_state = priv->control_state;
        bad_flow_control = priv->bad_flow_control;
        spin_unlock_irqrestore(&priv->lock, flags);

        old_iflag = old_termios->c_iflag;
        old_cflag = old_termios->c_cflag;

        /* Set the baud rate */
        if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
                /* reassert DTR and (maybe) RTS on transition from B0 */
                if ((old_cflag & CBAUD) == B0) {
                        control_state |= (TIOCM_DTR|TIOCM_RTS);
                        if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
                                err("Set DTR error");
                        /* don't set RTS if using hardware flow control */
                        if (!(old_cflag & CRTSCTS))
                                if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST
                                                                , 1) < 0)
                                        err("Set RTS error");
                }
        }

        baud = tty_get_baud_rate(tty);
        if (baud) {
                urb_value = BELKIN_SA_BAUD(baud);
                /* Clip to maximum speed */
                if (urb_value == 0)
                        urb_value = 1;
                /* Turn it back into a resulting real baud rate */
                baud = BELKIN_SA_BAUD(urb_value);

                /* Report the actual baud rate back to the caller */
                tty_encode_baud_rate(tty, baud, baud);
                if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
                        err("Set baudrate error");
        } else {
                /* Disable flow control */
                if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST,
                                                BELKIN_SA_FLOW_NONE) < 0)
                        err("Disable flowcontrol error");
                /* Drop RTS and DTR */
                control_state &= ~(TIOCM_DTR | TIOCM_RTS);
                if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
                        err("DTR LOW error");
                if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
                        err("RTS LOW error");
        }

        /* set the parity */
        if ((cflag ^ old_cflag) & (PARENB | PARODD)) {
                if (cflag & PARENB)
                        urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD
                                                : BELKIN_SA_PARITY_EVEN;
                else
                        urb_value = BELKIN_SA_PARITY_NONE;
                if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
                        err("Set parity error");
        }

        /* set the number of data bits */
        if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
                switch (cflag & CSIZE) {
                case CS5:
                        urb_value = BELKIN_SA_DATA_BITS(5);
                        break;
                case CS6:
                        urb_value = BELKIN_SA_DATA_BITS(6);
                        break;
                case CS7:
                        urb_value = BELKIN_SA_DATA_BITS(7);
                        break;
                case CS8:
                        urb_value = BELKIN_SA_DATA_BITS(8);
                        break;
                default: dbg("CSIZE was not CS5-CS8, using default of 8");
                        urb_value = BELKIN_SA_DATA_BITS(8);
                        break;
                }
                if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
                        err("Set data bits error");
        }

        /* set the number of stop bits */
        if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
                urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2)
                                                : BELKIN_SA_STOP_BITS(1);
                if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST,
                                                        urb_value) < 0)
                        err("Set stop bits error");
        }

        /* Set flow control */
        if (((iflag ^ old_iflag) & (IXOFF | IXON)) ||
                ((cflag ^ old_cflag) & CRTSCTS)) {
                urb_value = 0;
                if ((iflag & IXOFF) || (iflag & IXON))
                        urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
                else
                        urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);

                if (cflag & CRTSCTS)
                        urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
                else
                        urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);

                if (bad_flow_control)
                        urb_value &= ~(BELKIN_SA_FLOW_IRTS);

                if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
                        err("Set flow control error");
        }

        /* save off the modified port settings */
        spin_lock_irqsave(&priv->lock, flags);
        priv->control_state = control_state;
        spin_unlock_irqrestore(&priv->lock, flags);
} /* belkin_sa_set_termios */


static void belkin_sa_break_ctl(struct tty_struct *tty, int break_state)
{
        struct usb_serial_port *port = tty->driver_data;
        struct usb_serial *serial = port->serial;

        if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
                err("Set break_ctl %d", break_state);
}


static int belkin_sa_tiocmget(struct tty_struct *tty, struct file *file)
{
        struct usb_serial_port *port = tty->driver_data;
        struct belkin_sa_private *priv = usb_get_serial_port_data(port);
        unsigned long control_state;
        unsigned long flags;

        dbg("%s", __func__);

        spin_lock_irqsave(&priv->lock, flags);
        control_state = priv->control_state;
        spin_unlock_irqrestore(&priv->lock, flags);

        return control_state;
}


static int belkin_sa_tiocmset(struct tty_struct *tty, struct file *file,
                               unsigned int set, unsigned int clear)
{
        struct usb_serial_port *port = tty->driver_data;
        struct usb_serial *serial = port->serial;
        struct belkin_sa_private *priv = usb_get_serial_port_data(port);
        unsigned long control_state;
        unsigned long flags;
        int retval;
        int rts = 0;
        int dtr = 0;

        dbg("%s", __func__);

        spin_lock_irqsave(&priv->lock, flags);
        control_state = priv->control_state;

        if (set & TIOCM_RTS) {
                control_state |= TIOCM_RTS;
                rts = 1;
        }
        if (set & TIOCM_DTR) {
                control_state |= TIOCM_DTR;
                dtr = 1;
        }
        if (clear & TIOCM_RTS) {
                control_state &= ~TIOCM_RTS;
                rts = 0;
        }
        if (clear & TIOCM_DTR) {
                control_state &= ~TIOCM_DTR;
                dtr = 0;
        }

        priv->control_state = control_state;
        spin_unlock_irqrestore(&priv->lock, flags);

        retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
        if (retval < 0) {
                err("Set RTS error %d", retval);
                goto exit;
        }

        retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
        if (retval < 0) {
                err("Set DTR error %d", retval);
                goto exit;
        }
exit:
        return retval;
}


static int __init belkin_sa_init(void)
{
        int retval;
        retval = usb_serial_register(&belkin_device);
        if (retval)
                goto failed_usb_serial_register;
        retval = usb_register(&belkin_driver);
        if (retval)
                goto failed_usb_register;
        info(DRIVER_DESC " " DRIVER_VERSION);
        return 0;
failed_usb_register:
        usb_serial_deregister(&belkin_device);
failed_usb_serial_register:
        return retval;
}


static void __exit belkin_sa_exit (void)
{
        usb_deregister(&belkin_driver);
        usb_serial_deregister(&belkin_device);
}


module_init(belkin_sa_init);
module_exit(belkin_sa_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");