From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/input/serio/serport.c | 301 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 301 insertions(+) create mode 100644 drivers/input/serio/serport.c (limited to 'drivers/input/serio/serport.c') diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c new file mode 100644 index 000000000..69175b825 --- /dev/null +++ b/drivers/input/serio/serport.c @@ -0,0 +1,301 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Vojtech Pavlik "); +MODULE_DESCRIPTION("Input device TTY line discipline"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_LDISC(N_MOUSE); + +#define SERPORT_BUSY 1 +#define SERPORT_ACTIVE 2 +#define SERPORT_DEAD 3 + +struct serport { + struct tty_struct *tty; + wait_queue_head_t wait; + struct serio *serio; + struct serio_device_id id; + spinlock_t lock; + 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->ops->write(serport->tty, &data, 1) != 1); +} + +static int serport_serio_open(struct serio *serio) +{ + struct serport *serport = serio->port_data; + unsigned long flags; + + spin_lock_irqsave(&serport->lock, flags); + set_bit(SERPORT_ACTIVE, &serport->flags); + spin_unlock_irqrestore(&serport->lock, flags); + + return 0; +} + + +static void serport_serio_close(struct serio *serio) +{ + struct serport *serport = serio->port_data; + unsigned long flags; + + spin_lock_irqsave(&serport->lock, flags); + clear_bit(SERPORT_ACTIVE, &serport->flags); + set_bit(SERPORT_DEAD, &serport->flags); + spin_unlock_irqrestore(&serport->lock, flags); + + 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; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + serport = kzalloc(sizeof(struct serport), GFP_KERNEL); + if (!serport) + return -ENOMEM; + + serport->tty = tty; + spin_lock_init(&serport->lock); + init_waitqueue_head(&serport->wait); + + tty->disc_data = serport; + tty->receive_room = 256; + set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + + 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 and flags, 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; + unsigned long flags; + unsigned int ch_flags = 0; + int i; + + spin_lock_irqsave(&serport->lock, flags); + + if (!test_bit(SERPORT_ACTIVE, &serport->flags)) + goto out; + + for (i = 0; i < count; i++) { + if (fp) { + switch (fp[i]) { + case TTY_FRAME: + ch_flags = SERIO_FRAME; + break; + + case TTY_PARITY: + ch_flags = SERIO_PARITY; + break; + + default: + ch_flags = 0; + break; + } + } + + serio_interrupt(serport->serio, cp[i], ch_flags); + } + +out: + spin_unlock_irqrestore(&serport->lock, flags); +} + +/* + * 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; + struct serio *serio; + char name[64]; + + if (test_and_set_bit(SERPORT_BUSY, &serport->flags)) + return -EBUSY; + + serport->serio = serio = kzalloc(sizeof(struct serio), GFP_KERNEL); + if (!serio) + return -ENOMEM; + + strlcpy(serio->name, "Serial port", sizeof(serio->name)); + snprintf(serio->phys, sizeof(serio->phys), "%s/serio0", tty_name(tty, name)); + serio->id = serport->id; + serio->id.type = SERIO_RS232; + serio->write = serport_serio_write; + serio->open = serport_serio_open; + serio->close = serport_serio_close; + serio->port_data = serport; + serio->dev.parent = tty->dev; + + serio_register_port(serport->serio); + printk(KERN_INFO "serio: Serial port %s\n", tty_name(tty, name)); + + wait_event_interruptible(serport->wait, test_bit(SERPORT_DEAD, &serport->flags)); + serio_unregister_port(serport->serio); + serport->serio = NULL; + + clear_bit(SERPORT_DEAD, &serport->flags); + clear_bit(SERPORT_BUSY, &serport->flags); + + return 0; +} + +static void serport_set_type(struct tty_struct *tty, unsigned long type) +{ + struct serport *serport = tty->disc_data; + + serport->id.proto = type & 0x000000ff; + serport->id.id = (type & 0x0000ff00) >> 8; + serport->id.extra = (type & 0x00ff0000) >> 16; +} + +/* + * 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) +{ + if (cmd == SPIOCSTYPE) { + unsigned long type; + + if (get_user(type, (unsigned long __user *) arg)) + return -EFAULT; + + serport_set_type(tty, type); + return 0; + } + + return -EINVAL; +} + +#ifdef CONFIG_COMPAT +#define COMPAT_SPIOCSTYPE _IOW('q', 0x01, compat_ulong_t) +static long serport_ldisc_compat_ioctl(struct tty_struct *tty, + struct file *file, + unsigned int cmd, unsigned long arg) +{ + if (cmd == COMPAT_SPIOCSTYPE) { + void __user *uarg = compat_ptr(arg); + compat_ulong_t compat_type; + + if (get_user(compat_type, (compat_ulong_t __user *)uarg)) + return -EFAULT; + + serport_set_type(tty, compat_type); + return 0; + } + + return -EINVAL; +} +#endif + +static void serport_ldisc_write_wakeup(struct tty_struct * tty) +{ + struct serport *serport = (struct serport *) tty->disc_data; + unsigned long flags; + + spin_lock_irqsave(&serport->lock, flags); + if (test_bit(SERPORT_ACTIVE, &serport->flags)) + serio_drv_write_wakeup(serport->serio); + spin_unlock_irqrestore(&serport->lock, flags); +} + +/* + * The line discipline structure. + */ + +static struct tty_ldisc_ops serport_ldisc = { + .owner = THIS_MODULE, + .name = "input", + .open = serport_ldisc_open, + .close = serport_ldisc_close, + .read = serport_ldisc_read, + .ioctl = serport_ldisc_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = serport_ldisc_compat_ioctl, +#endif + .receive_buf = serport_ldisc_receive, + .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_unregister_ldisc(N_MOUSE); +} + +module_init(serport_init); +module_exit(serport_exit); -- cgit v1.2.3-54-g00ecf