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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 02:20:36 +0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 02:20:36 +0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/input/serio/serport.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/input/serio/serport.c')
-rw-r--r-- | drivers/input/serio/serport.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c new file mode 100644 index 000000000000..22f73683952b --- /dev/null +++ b/drivers/input/serio/serport.c @@ -0,0 +1,226 @@ +/* + * Input device TTY line discipline + * + * Copyright (c) 1999-2002 Vojtech Pavlik + * + * 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 version 2 as published by + * the Free Software Foundation. + */ + +#include <asm/uaccess.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/serio.h> +#include <linux/tty.h> + +MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); +MODULE_DESCRIPTION("Input device TTY line discipline"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_LDISC(N_MOUSE); + +#define SERPORT_BUSY 1 + +struct serport { + struct tty_struct *tty; + wait_queue_head_t wait; + struct serio *serio; + unsigned long flags; +}; + +/* + * Callback functions from the serio code. + */ + +static int serport_serio_write(struct serio *serio, unsigned char data) +{ + struct serport *serport = serio->port_data; + return -(serport->tty->driver->write(serport->tty, &data, 1) != 1); +} + +static void serport_serio_close(struct serio *serio) +{ + struct serport *serport = serio->port_data; + + serport->serio->id.type = 0; + wake_up_interruptible(&serport->wait); +} + +/* + * serport_ldisc_open() is the routine that is called upon setting our line + * discipline on a tty. It prepares the serio struct. + */ + +static int serport_ldisc_open(struct tty_struct *tty) +{ + struct serport *serport; + struct serio *serio; + char name[64]; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + serport = kmalloc(sizeof(struct serport), GFP_KERNEL); + serio = kmalloc(sizeof(struct serio), GFP_KERNEL); + if (unlikely(!serport || !serio)) { + kfree(serport); + kfree(serio); + return -ENOMEM; + } + + memset(serport, 0, sizeof(struct serport)); + serport->serio = serio; + set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + serport->tty = tty; + tty->disc_data = serport; + + memset(serio, 0, sizeof(struct serio)); + strlcpy(serio->name, "Serial port", sizeof(serio->name)); + snprintf(serio->phys, sizeof(serio->phys), "%s/serio0", tty_name(tty, name)); + serio->id.type = SERIO_RS232; + serio->write = serport_serio_write; + serio->close = serport_serio_close; + serio->port_data = 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); +} + +/* + * 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. + * + * FIXME: We should get pt_regs from the tty layer and forward them to + * serio_interrupt here. + */ + +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++) + serio_interrupt(serport->serio, cp[i], 0, NULL); +} + +/* + * 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 __user * buf, size_t nr) +{ + struct serport *serport = (struct serport*) tty->disc_data; + char name[64]; + + if (test_and_set_bit(SERPORT_BUSY, &serport->flags)) + return -EBUSY; + + serio_register_port(serport->serio); + printk(KERN_INFO "serio: Serial port %s\n", tty_name(tty, name)); + wait_event_interruptible(serport->wait, !serport->serio->id.type); + serio_unregister_port(serport->serio); + + clear_bit(SERPORT_BUSY, &serport->flags); + + 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; + struct serio *serio = serport->serio; + unsigned long type; + + if (cmd == SPIOCSTYPE) { + if (get_user(type, (unsigned long __user *) arg)) + return -EFAULT; + + serio->id.proto = type & 0x000000ff; + serio->id.id = (type & 0x0000ff00) >> 8; + serio->id.extra = (type & 0x00ff0000) >> 16; + + return 0; + } + + return -EINVAL; +} + +static void serport_ldisc_write_wakeup(struct tty_struct * tty) +{ + struct serport *sp = (struct serport *) tty->disc_data; + + serio_drv_write_wakeup(sp->serio); +} + +/* + * The line discipline structure. + */ + +static struct tty_ldisc serport_ldisc = { + .owner = THIS_MODULE, + .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, + .write_wakeup = serport_ldisc_write_wakeup +}; + +/* + * The functions for insering/removing us as a module. + */ + +static int __init serport_init(void) +{ + int retval; + retval = tty_register_ldisc(N_MOUSE, &serport_ldisc); + if (retval) + printk(KERN_ERR "serport.c: Error registering line discipline.\n"); + + return retval; +} + +static void __exit serport_exit(void) +{ + tty_register_ldisc(N_MOUSE, NULL); +} + +module_init(serport_init); +module_exit(serport_exit); |