interface.c

LINUX 2.6.17.4的源码

/*
 * interface to user space for the gigaset driver
 *
 * Copyright (c) 2004 by Hansjoerg Lipp <[e-mail]>
 *
 * =====================================================================
 *    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.
 * =====================================================================
 */

#include "gigaset.h"
#include <linux/gigaset_dev.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>

/*** our ioctls ***/

static int if_lock(struct cardstate *cs, int *arg)
{
	int cmd = *arg;

	gig_dbg(DEBUG_IF, "%u: if_lock (%d)", cs->minor_index, cmd);

	if (cmd > 1)
		return -EINVAL;

	if (cmd < 0) {
		*arg = atomic_read(&cs->mstate) == MS_LOCKED; //FIXME remove?
		return 0;
	}

	if (!cmd && atomic_read(&cs->mstate) == MS_LOCKED
	    && cs->connected) {
		cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
		cs->ops->baud_rate(cs, B115200);
		cs->ops->set_line_ctrl(cs, CS8);
		cs->control_state = TIOCM_DTR|TIOCM_RTS;
	}

	cs->waiting = 1;
	if (!gigaset_add_event(cs, &cs->at_state, EV_IF_LOCK,
			       NULL, cmd, NULL)) {
		cs->waiting = 0;
		return -ENOMEM;
	}

	gig_dbg(DEBUG_CMD, "scheduling IF_LOCK");
	gigaset_schedule_event(cs);

	wait_event(cs->waitqueue, !cs->waiting);

	if (cs->cmd_result >= 0) {
		*arg = cs->cmd_result;
		return 0;
	}

	return cs->cmd_result;
}

static int if_version(struct cardstate *cs, unsigned arg[4])
{
	static const unsigned version[4] = GIG_VERSION;
	static const unsigned compat[4] = GIG_COMPAT;
	unsigned cmd = arg[0];

	gig_dbg(DEBUG_IF, "%u: if_version (%d)", cs->minor_index, cmd);

	switch (cmd) {
	case GIGVER_DRIVER:
		memcpy(arg, version, sizeof version);
		return 0;
	case GIGVER_COMPAT:
		memcpy(arg, compat, sizeof compat);
		return 0;
	case GIGVER_FWBASE:
		cs->waiting = 1;
		if (!gigaset_add_event(cs, &cs->at_state, EV_IF_VER,
				       NULL, 0, arg)) {
			cs->waiting = 0;
			return -ENOMEM;
		}

		gig_dbg(DEBUG_CMD, "scheduling IF_VER");
		gigaset_schedule_event(cs);

		wait_event(cs->waitqueue, !cs->waiting);

		if (cs->cmd_result >= 0)
			return 0;

		return cs->cmd_result;
	default:
		return -EINVAL;
	}
}

static int if_config(struct cardstate *cs, int *arg)
{
	gig_dbg(DEBUG_IF, "%u: if_config (%d)", cs->minor_index, *arg);

	if (*arg != 1)
		return -EINVAL;

	if (atomic_read(&cs->mstate) != MS_LOCKED)
		return -EBUSY;

	if (!cs->connected) {
		err("not connected!");
		return -ENODEV;
	}

	*arg = 0;
	return gigaset_enterconfigmode(cs);
}

/*** the terminal driver ***/
/* stolen from usbserial and some other tty drivers */

static int  if_open(struct tty_struct *tty, struct file *filp);
static void if_close(struct tty_struct *tty, struct file *filp);
static int  if_ioctl(struct tty_struct *tty, struct file *file,
		     unsigned int cmd, unsigned long arg);
static int  if_write_room(struct tty_struct *tty);
static int  if_chars_in_buffer(struct tty_struct *tty);
static void if_throttle(struct tty_struct *tty);
static void if_unthrottle(struct tty_struct *tty);
static void if_set_termios(struct tty_struct *tty, struct termios *old);
static int  if_tiocmget(struct tty_struct *tty, struct file *file);
static int  if_tiocmset(struct tty_struct *tty, struct file *file,
			unsigned int set, unsigned int clear);
static int  if_write(struct tty_struct *tty,
		     const unsigned char *buf, int count);

static struct tty_operations if_ops = {
	.open =			if_open,
	.close =		if_close,
	.ioctl =		if_ioctl,
	.write =		if_write,
	.write_room =		if_write_room,
	.chars_in_buffer =	if_chars_in_buffer,
	.set_termios =		if_set_termios,
	.throttle =		if_throttle,
	.unthrottle =		if_unthrottle,
#if 0
	.break_ctl =		serial_break,
#endif
	.tiocmget =		if_tiocmget,
	.tiocmset =		if_tiocmset,
};

static int if_open(struct tty_struct *tty, struct file *filp)
{
	struct cardstate *cs;
	unsigned long flags;

	gig_dbg(DEBUG_IF, "%d+%d: %s()",
		tty->driver->minor_start, tty->index, __func__);

	tty->driver_data = NULL;

	cs = gigaset_get_cs_by_tty(tty);
	if (!cs)
		return -ENODEV;

	if (mutex_lock_interruptible(&cs->mutex))
		return -ERESTARTSYS; // FIXME -EINTR?
	tty->driver_data = cs;

	++cs->open_count;

	if (cs->open_count == 1) {
		spin_lock_irqsave(&cs->lock, flags);
		cs->tty = tty;
		spin_unlock_irqrestore(&cs->lock, flags);
		tty->low_latency = 1; //FIXME test
	}

	mutex_unlock(&cs->mutex);
	return 0;
}

static void if_close(struct tty_struct *tty, struct file *filp)
{
	struct cardstate *cs;
	unsigned long flags;

	cs = (struct cardstate *) tty->driver_data;
	if (!cs) {
		err("cs==NULL in %s", __func__);
		return;
	}

	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);

	mutex_lock(&cs->mutex);

	if (!cs->open_count)
		warn("%s: device not opened", __func__);
	else {
		if (!--cs->open_count) {
			spin_lock_irqsave(&cs->lock, flags);
			cs->tty = NULL;
			spin_unlock_irqrestore(&cs->lock, flags);
		}
	}

	mutex_unlock(&cs->mutex);
}

static int if_ioctl(struct tty_struct *tty, struct file *file,
		    unsigned int cmd, unsigned long arg)
{
	struct cardstate *cs;
	int retval = -ENODEV;
	int int_arg;
	unsigned char buf[6];
	unsigned version[4];

	cs = (struct cardstate *) tty->driver_data;
	if (!cs) {
		err("cs==NULL in %s", __func__);
		return -ENODEV;
	}

	gig_dbg(DEBUG_IF, "%u: %s(0x%x)", cs->minor_index, __func__, cmd);

	if (mutex_lock_interruptible(&cs->mutex))
		return -ERESTARTSYS; // FIXME -EINTR?

	if (!cs->open_count)
		warn("%s: device not opened", __func__);
	else {
		retval = 0;
		switch (cmd) {
		case GIGASET_REDIR:
			retval = get_user(int_arg, (int __user *) arg);
			if (retval >= 0)
				retval = if_lock(cs, &int_arg);
			if (retval >= 0)
				retval = put_user(int_arg, (int __user *) arg);
			break;
		case GIGASET_CONFIG:
			retval = get_user(int_arg, (int __user *) arg);
			if (retval >= 0)
				retval = if_config(cs, &int_arg);
			if (retval >= 0)
				retval = put_user(int_arg, (int __user *) arg);
			break;
		case GIGASET_BRKCHARS:
			//FIXME test if MS_LOCKED
			if (!cs->connected) {
				gig_dbg(DEBUG_ANY,
				    "can't communicate with unplugged device");
				retval = -ENODEV;
				break;
			}
			retval = copy_from_user(&buf,
					(const unsigned char __user *) arg, 6)
				? -EFAULT : 0;
			if (retval >= 0) {
				gigaset_dbg_buffer(DEBUG_IF, "GIGASET_BRKCHARS",
						6, (const unsigned char *) arg);
				retval = cs->ops->brkchars(cs, buf);
			}
			break;
		case GIGASET_VERSION:
			retval = copy_from_user(version,
					(unsigned __user *) arg, sizeof version)
				? -EFAULT : 0;
			if (retval >= 0)
				retval = if_version(cs, version);
			if (retval >= 0)
				retval = copy_to_user((unsigned __user *) arg,
						      version, sizeof version)
					? -EFAULT : 0;
			break;
		default:
			gig_dbg(DEBUG_ANY, "%s: arg not supported - 0x%04x",
				__func__, cmd);
			retval = -ENOIOCTLCMD;
		}
	}

	mutex_unlock(&cs->mutex);

	return retval;
}

static int if_tiocmget(struct tty_struct *tty, struct file *file)
{
	struct cardstate *cs;
	int retval;

	cs = (struct cardstate *) tty->driver_data;
	if (!cs) {
		err("cs==NULL in %s", __func__);
		return -ENODEV;
	}

	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);

	if (mutex_lock_interruptible(&cs->mutex))
		return -ERESTARTSYS; // FIXME -EINTR?

	// FIXME read from device?
	retval = cs->control_state & (TIOCM_RTS|TIOCM_DTR);

	mutex_unlock(&cs->mutex);

	return retval;
}

static int if_tiocmset(struct tty_struct *tty, struct file *file,
		       unsigned int set, unsigned int clear)
{
	struct cardstate *cs;
	int retval;
	unsigned mc;

	cs = (struct cardstate *) tty->driver_data;
	if (!cs) {
		err("cs==NULL in %s", __func__);
		return -ENODEV;
	}

	gig_dbg(DEBUG_IF, "%u: %s(0x%x, 0x%x)",
		cs->minor_index, __func__, set, clear);

	if (mutex_lock_interruptible(&cs->mutex))
		return -ERESTARTSYS; // FIXME -EINTR?

	if (!cs->connected) {
		gig_dbg(DEBUG_ANY, "can't communicate with unplugged device");
		retval = -ENODEV;
	} else {
		mc = (cs->control_state | set) & ~clear & (TIOCM_RTS|TIOCM_DTR);
		retval = cs->ops->set_modem_ctrl(cs, cs->control_state, mc);
		cs->control_state = mc;
	}

	mutex_unlock(&cs->mutex);

	return retval;
}

static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
	struct cardstate *cs;
	int retval = -ENODEV;

	cs = (struct cardstate *) tty->driver_data;
	if (!cs) {
		err("cs==NULL in %s", __func__);
		return -ENODEV;
	}

	gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);

	if (mutex_lock_interruptible(&cs->mutex))
		return -ERESTARTSYS; // FIXME -EINTR?