diff options
author | Ralf Baechle <ralf@linux-mips.org> | 2000-06-25 01:20:01 +0000 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 2000-06-25 01:20:01 +0000 |
commit | 3797ba0b62debb71af4606910acacc9896a9ae3b (patch) | |
tree | 414eea76253c7871bfdf3bd9d1817771eb40917c /drivers/char/joystick/serport.c | |
parent | 2b6c0c580795a4404f72d2a794214dd9e080709d (diff) |
Merge with Linux 2.4.0-test2.
Diffstat (limited to 'drivers/char/joystick/serport.c')
-rw-r--r-- | drivers/char/joystick/serport.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/drivers/char/joystick/serport.c b/drivers/char/joystick/serport.c new file mode 100644 index 000000000..453e674d7 --- /dev/null +++ b/drivers/char/joystick/serport.c @@ -0,0 +1,220 @@ +/* + * $Id: serport.c,v 1.4 2000/05/29 10:54:53 vojtech Exp $ + * + * Copyright (c) 1999-2000 Vojtech Pavlik + * + * Sponsored by SuSE + */ + +/* + * This is a module that converts a tty line into a much simpler + * 'serial io port' abstraction that the input device drivers use. + */ + +/* + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * Should you need to contact me, the author, you can do so either by + * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail: + * Vojtech Pavlik, Ucitelska 1576, Prague 8, 182 00 Czech Republic + */ + +#include <asm/uaccess.h> +#include <linux/kernel.h> +#include <linux/malloc.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/serio.h> +#include <linux/tty.h> + +struct serport { + struct tty_struct *tty; + wait_queue_head_t wait; + struct serio serio; +}; + +/* + * Callback functions from the serio code. + */ + +static int serport_serio_write(struct serio *serio, unsigned char data) +{ + struct serport *serport = serio->driver; + return -(serport->tty->driver.write(serport->tty, 0, &data, 1) != 1); +} + +static int serport_serio_open(struct serio *serio) +{ + return 0; +} + +static void serport_serio_close(struct serio *serio) +{ + struct serport *serport = serio->driver; + wake_up_interruptible(&serport->wait); +} + +/* + * serport_ldisc_open() is the routine that is called upon setting our line + * discipline on a tty. It looks for the Mag, and if found, registers + * it as a joystick device. + */ + +static int serport_ldisc_open(struct tty_struct *tty) +{ + struct serport *serport; + + MOD_INC_USE_COUNT; + + if (!(serport = kmalloc(sizeof(struct serport), GFP_KERNEL))) { + MOD_DEC_USE_COUNT; + return -ENOMEM; + } + + memset(serport, 0, sizeof(struct serport)); + + serport->tty = tty; + tty->disc_data = serport; + + serport->serio.type = SERIO_RS232; + serport->serio.write = serport_serio_write; + serport->serio.open = serport_serio_open; + serport->serio.close = serport_serio_close; + serport->serio.driver = serport; + + init_waitqueue_head(&serport->wait); + + return 0; +} + +/* + * serport_ldisc_close() is the opposite of serport_ldisc_open() + */ + +static void serport_ldisc_close(struct tty_struct *tty) +{ + struct serport *serport = (struct serport*) tty->disc_data; + kfree(serport); + MOD_DEC_USE_COUNT; +} + +/* + * serport_ldisc_receive() is called by the low level tty driver when characters + * are ready for us. We forward the characters, one by one to the 'interrupt' + * routine. + */ + +static void serport_ldisc_receive(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) +{ + struct serport *serport = (struct serport*) tty->disc_data; + int i; + for (i = 0; i < count; i++) + if (serport->serio.dev) + serport->serio.dev->interrupt(&serport->serio, cp[i], 0); +} + +/* + * serport_ldisc_room() reports how much room we do have for receiving data. + * Although we in fact have infinite room, we need to specify some value + * here, and 256 seems to be reasonable. + */ + +static int serport_ldisc_room(struct tty_struct *tty) +{ + return 256; +} + +/* + * serport_ldisc_read() just waits indefinitely if everything goes well. + * However, when the serio driver closes the serio port, it finishes, + * returning 0 characters. + */ + +static ssize_t serport_ldisc_read(struct tty_struct * tty, struct file * file, unsigned char * buf, size_t nr) +{ + struct serport *serport = (struct serport*) tty->disc_data; + DECLARE_WAITQUEUE(wait, current); + char name[32]; + + sprintf(name, tty->driver.name, MINOR(tty->device) - tty->driver.minor_start); + + serio_register_port(&serport->serio); + + printk(KERN_INFO "serio%d: Serial port %s\n", serport->serio.number, name); + + add_wait_queue(&serport->wait, &wait); + current->state = TASK_INTERRUPTIBLE; + + while(serport->serio.type && !signal_pending(current)) schedule(); + + current->state = TASK_RUNNING; + remove_wait_queue(&serport->wait, &wait); + + serio_unregister_port(&serport->serio); + + return 0; +} + +/* + * serport_ldisc_ioctl() allows to set the port protocol, and device ID + */ + +static int serport_ldisc_ioctl(struct tty_struct * tty, struct file * file, unsigned int cmd, unsigned long arg) +{ + struct serport *serport = (struct serport*) tty->disc_data; + + switch (cmd) { + case SPIOCSTYPE: + return get_user(serport->serio.type, (unsigned long *) arg); + } + + return -EINVAL; +} + +/* + * The line discipline structure. + */ + +static struct tty_ldisc serport_ldisc = { + name: "input", + open: serport_ldisc_open, + close: serport_ldisc_close, + read: serport_ldisc_read, + ioctl: serport_ldisc_ioctl, + receive_buf: serport_ldisc_receive, + receive_room: serport_ldisc_room, +}; + +/* + * The functions for insering/removing us as a module. + */ + +int __init serport_init(void) +{ + if (tty_register_ldisc(N_MOUSE, &serport_ldisc)) { + printk(KERN_ERR "serport.c: Error registering line discipline.\n"); + return -ENODEV; + } + + return 0; +} + +void __exit serport_exit(void) +{ + tty_register_ldisc(N_MOUSE, NULL); +} + +module_init(serport_init); +module_exit(serport_exit); |