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authorRalf Baechle <ralf@linux-mips.org>2000-06-25 01:20:01 +0000
committerRalf Baechle <ralf@linux-mips.org>2000-06-25 01:20:01 +0000
commit3797ba0b62debb71af4606910acacc9896a9ae3b (patch)
tree414eea76253c7871bfdf3bd9d1817771eb40917c /drivers/char/joystick/serport.c
parent2b6c0c580795a4404f72d2a794214dd9e080709d (diff)
Merge with Linux 2.4.0-test2.
Diffstat (limited to 'drivers/char/joystick/serport.c')
-rw-r--r--drivers/char/joystick/serport.c220
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);