2 * $Id: tsdev.c,v 1.15 2002/04/10 16:50:19 jsimmons Exp $
4 * Copyright (c) 2001 "Crazy" james Simmons
6 * Compaq touchscreen protocol driver. The protocol emulated by this driver
7 * is obsolete; for new programs use the tslib library which can read directly
8 * from evdev and perform dejittering, variance filtering and calibration -
9 * all in user space, not at kernel level. The meaning of this driver is
10 * to allow usage of newer input drivers with old applications that use the
11 * old /dev/h3600_ts and /dev/h3600_tsraw devices.
13 * 09-Apr-2004: Andrew Zabolotny <zap@homelink.ru>
14 * Fixed to actually work, not just output random numbers.
15 * Added support for both h3600_ts and h3600_tsraw protocol
20 * This program is free software; you can redistribute it and/or modify
21 * it under the terms of the GNU General Public License as published by
22 * the Free Software Foundation; either version 2 of the License, or
23 * (at your option) any later version.
25 * This program is distributed in the hope that it will be useful,
26 * but WITHOUT ANY WARRANTY; without even the implied warranty of
27 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
28 * GNU General Public License for more details.
30 * You should have received a copy of the GNU General Public License
31 * along with this program; if not, write to the Free Software
32 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
34 * Should you need to contact me, the author, you can do so either by
35 * e-mail - mail your message to <jsimmons@infradead.org>.
38 #define TSDEV_MINOR_BASE 128
39 #define TSDEV_MINORS 32
40 /* First 16 devices are h3600_ts compatible; second 16 are h3600_tsraw */
41 #define TSDEV_MINOR_MASK 15
42 #define TSDEV_BUFFER_SIZE 64
44 #include <linux/slab.h>
45 #include <linux/poll.h>
46 #include <linux/module.h>
47 #include <linux/moduleparam.h>
48 #include <linux/init.h>
49 #include <linux/input.h>
50 #include <linux/major.h>
51 #include <linux/random.h>
52 #include <linux/time.h>
53 #include <linux/device.h>
55 #ifndef CONFIG_INPUT_TSDEV_SCREEN_X
56 #define CONFIG_INPUT_TSDEV_SCREEN_X 240
58 #ifndef CONFIG_INPUT_TSDEV_SCREEN_Y
59 #define CONFIG_INPUT_TSDEV_SCREEN_Y 320
62 /* This driver emulates both protocols of the old h3600_ts and h3600_tsraw
63 * devices. The first one must output X/Y data in 'cooked' format, e.g.
64 * filtered, dejittered and calibrated. Second device just outputs raw
65 * data received from the hardware.
67 * This driver doesn't support filtering and dejittering; it supports only
68 * calibration. Filtering and dejittering must be done in the low-level
69 * driver, if needed, because it may gain additional benefits from knowing
70 * the low-level details, the nature of noise and so on.
72 * The driver precomputes a calibration matrix given the initial xres and
73 * yres values (quite innacurate for most touchscreens) that will result
74 * in a more or less expected range of output values. The driver supports
75 * the TS_SET_CAL ioctl, which will replace the calibration matrix with a
76 * new one, supposedly generated from the values taken from the raw device.
79 MODULE_AUTHOR("James Simmons <jsimmons@transvirtual.com>");
80 MODULE_DESCRIPTION("Input driver to touchscreen converter");
81 MODULE_LICENSE("GPL");
83 static int xres = CONFIG_INPUT_TSDEV_SCREEN_X;
84 module_param(xres, uint, 0);
85 MODULE_PARM_DESC(xres, "Horizontal screen resolution (can be negative for X-mirror)");
87 static int yres = CONFIG_INPUT_TSDEV_SCREEN_Y;
88 module_param(yres, uint, 0);
89 MODULE_PARM_DESC(yres, "Vertical screen resolution (can be negative for Y-mirror)");
91 /* From Compaq's Touch Screen Specification version 0.2 (draft) */
99 struct ts_calibration {
112 struct input_handle handle;
113 wait_queue_head_t wait;
114 struct list_head client_list;
115 spinlock_t client_lock; /* protects client_list */
120 struct ts_calibration cal;
123 struct tsdev_client {
124 struct fasync_struct *fasync;
125 struct list_head node;
127 struct ts_event buffer[TSDEV_BUFFER_SIZE];
129 spinlock_t buffer_lock; /* protects access to buffer, head and tail */
133 /* The following ioctl codes are defined ONLY for backward compatibility.
134 * Don't use tsdev for new developement; use the tslib library instead.
135 * Touchscreen calibration is a fully userspace task.
137 /* Use 'f' as magic number */
138 #define IOC_H3600_TS_MAGIC 'f'
139 #define TS_GET_CAL _IOR(IOC_H3600_TS_MAGIC, 10, struct ts_calibration)
140 #define TS_SET_CAL _IOW(IOC_H3600_TS_MAGIC, 11, struct ts_calibration)
142 static struct tsdev *tsdev_table[TSDEV_MINORS/2];
143 static DEFINE_MUTEX(tsdev_table_mutex);
145 static int tsdev_fasync(int fd, struct file *file, int on)
147 struct tsdev_client *client = file->private_data;
150 retval = fasync_helper(fd, file, on, &client->fasync);
152 return retval < 0 ? retval : 0;
155 static void tsdev_free(struct device *dev)
157 struct tsdev *tsdev = container_of(dev, struct tsdev, dev);
162 static void tsdev_attach_client(struct tsdev *tsdev, struct tsdev_client *client)
164 spin_lock(&tsdev->client_lock);
165 list_add_tail_rcu(&client->node, &tsdev->client_list);
166 spin_unlock(&tsdev->client_lock);
170 static void tsdev_detach_client(struct tsdev *tsdev, struct tsdev_client *client)
172 spin_lock(&tsdev->client_lock);
173 list_del_rcu(&client->node);
174 spin_unlock(&tsdev->client_lock);
178 static int tsdev_open_device(struct tsdev *tsdev)
182 retval = mutex_lock_interruptible(&tsdev->mutex);
188 else if (!tsdev->open++) {
189 retval = input_open_device(&tsdev->handle);
194 mutex_unlock(&tsdev->mutex);
198 static void tsdev_close_device(struct tsdev *tsdev)
200 mutex_lock(&tsdev->mutex);
202 if (tsdev->exist && !--tsdev->open)
203 input_close_device(&tsdev->handle);
205 mutex_unlock(&tsdev->mutex);
209 * Wake up users waiting for IO so they can disconnect from
212 static void tsdev_hangup(struct tsdev *tsdev)
214 struct tsdev_client *client;
216 spin_lock(&tsdev->client_lock);
217 list_for_each_entry(client, &tsdev->client_list, node)
218 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
219 spin_unlock(&tsdev->client_lock);
221 wake_up_interruptible(&tsdev->wait);
224 static int tsdev_release(struct inode *inode, struct file *file)
226 struct tsdev_client *client = file->private_data;
227 struct tsdev *tsdev = client->tsdev;
229 tsdev_fasync(-1, file, 0);
230 tsdev_detach_client(tsdev, client);
233 tsdev_close_device(tsdev);
234 put_device(&tsdev->dev);
239 static int tsdev_open(struct inode *inode, struct file *file)
241 int i = iminor(inode) - TSDEV_MINOR_BASE;
242 struct tsdev_client *client;
246 printk(KERN_WARNING "tsdev (compaq touchscreen emulation) is scheduled "
247 "for removal.\nSee Documentation/feature-removal-schedule.txt "
250 if (i >= TSDEV_MINORS)
253 error = mutex_lock_interruptible(&tsdev_table_mutex);
256 tsdev = tsdev_table[i & TSDEV_MINOR_MASK];
258 get_device(&tsdev->dev);
259 mutex_unlock(&tsdev_table_mutex);
264 client = kzalloc(sizeof(struct tsdev_client), GFP_KERNEL);
270 spin_lock_init(&client->buffer_lock);
271 client->tsdev = tsdev;
272 client->raw = i >= TSDEV_MINORS / 2;
273 tsdev_attach_client(tsdev, client);
275 error = tsdev_open_device(tsdev);
277 goto err_free_client;
279 file->private_data = client;
283 tsdev_detach_client(tsdev, client);
286 put_device(&tsdev->dev);
290 static int tsdev_fetch_next_event(struct tsdev_client *client,
291 struct ts_event *event)
295 spin_lock_irq(&client->buffer_lock);
297 have_event = client->head != client->tail;
299 *event = client->buffer[client->tail++];
300 client->tail &= TSDEV_BUFFER_SIZE - 1;
303 spin_unlock_irq(&client->buffer_lock);
308 static ssize_t tsdev_read(struct file *file, char __user *buffer, size_t count,
311 struct tsdev_client *client = file->private_data;
312 struct tsdev *tsdev = client->tsdev;
313 struct ts_event event;
316 if (client->head == client->tail && tsdev->exist &&
317 (file->f_flags & O_NONBLOCK))
320 retval = wait_event_interruptible(tsdev->wait,
321 client->head != client->tail || !tsdev->exist);
328 while (retval + sizeof(struct ts_event) <= count &&
329 tsdev_fetch_next_event(client, &event)) {
331 if (copy_to_user(buffer + retval, &event,
332 sizeof(struct ts_event)))
335 retval += sizeof(struct ts_event);
341 /* No kernel lock - fine */
342 static unsigned int tsdev_poll(struct file *file, poll_table *wait)
344 struct tsdev_client *client = file->private_data;
345 struct tsdev *tsdev = client->tsdev;
347 poll_wait(file, &tsdev->wait, wait);
348 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) |
349 (tsdev->exist ? 0 : (POLLHUP | POLLERR));
352 static long tsdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
354 struct tsdev_client *client = file->private_data;
355 struct tsdev *tsdev = client->tsdev;
358 retval = mutex_lock_interruptible(&tsdev->mutex);
370 if (copy_to_user((void __user *)arg, &tsdev->cal,
371 sizeof (struct ts_calibration)))
376 if (copy_from_user(&tsdev->cal, (void __user *)arg,
377 sizeof(struct ts_calibration)))
387 mutex_unlock(&tsdev->mutex);
391 static const struct file_operations tsdev_fops = {
392 .owner = THIS_MODULE,
394 .release = tsdev_release,
397 .fasync = tsdev_fasync,
398 .unlocked_ioctl = tsdev_ioctl,
401 static void tsdev_pass_event(struct tsdev *tsdev, struct tsdev_client *client,
402 int x, int y, int pressure, int millisecs)
404 struct ts_event *event;
407 /* Interrupts are already disabled, just acquire the lock */
408 spin_lock(&client->buffer_lock);
410 event = &client->buffer[client->head++];
411 client->head &= TSDEV_BUFFER_SIZE - 1;
415 x = ((x * tsdev->cal.xscale) >> 8) + tsdev->cal.xtrans;
416 y = ((y * tsdev->cal.yscale) >> 8) + tsdev->cal.ytrans;
417 if (tsdev->cal.xyswap) {
418 tmp = x; x = y; y = tmp;
422 event->millisecs = millisecs;
425 event->pressure = pressure;
427 spin_unlock(&client->buffer_lock);
429 kill_fasync(&client->fasync, SIGIO, POLL_IN);
432 static void tsdev_distribute_event(struct tsdev *tsdev)
434 struct tsdev_client *client;
438 do_gettimeofday(&time);
439 millisecs = time.tv_usec / 1000;
441 list_for_each_entry_rcu(client, &tsdev->client_list, node)
442 tsdev_pass_event(tsdev, client,
444 tsdev->pressure, millisecs);
447 static void tsdev_event(struct input_handle *handle, unsigned int type,
448 unsigned int code, int value)
450 struct tsdev *tsdev = handle->private;
451 struct input_dev *dev = handle->dev;
452 int wake_up_readers = 0;
468 if (value > dev->absmax[ABS_PRESSURE])
469 value = dev->absmax[ABS_PRESSURE];
470 value -= dev->absmin[ABS_PRESSURE];
473 tsdev->pressure = value;
485 else if (tsdev->x > xres)
493 else if (tsdev->y > yres)
500 if (code == BTN_TOUCH || code == BTN_MOUSE) {
508 if (!tsdev->pressure)
516 if (code == SYN_REPORT) {
517 tsdev_distribute_event(tsdev);
524 wake_up_interruptible(&tsdev->wait);
527 static int tsdev_install_chrdev(struct tsdev *tsdev)
529 tsdev_table[tsdev->minor] = tsdev;
533 static void tsdev_remove_chrdev(struct tsdev *tsdev)
535 mutex_lock(&tsdev_table_mutex);
536 tsdev_table[tsdev->minor] = NULL;
537 mutex_unlock(&tsdev_table_mutex);
541 * Mark device non-existant. This disables writes, ioctls and
542 * prevents new users from opening the device. Already posted
543 * blocking reads will stay, however new ones will fail.
545 static void tsdev_mark_dead(struct tsdev *tsdev)
547 mutex_lock(&tsdev->mutex);
549 mutex_unlock(&tsdev->mutex);
552 static void tsdev_cleanup(struct tsdev *tsdev)
554 struct input_handle *handle = &tsdev->handle;
556 tsdev_mark_dead(tsdev);
558 tsdev_remove_chrdev(tsdev);
560 /* tsdev is marked dead so noone else accesses tsdev->open */
562 input_close_device(handle);
565 static int tsdev_connect(struct input_handler *handler, struct input_dev *dev,
566 const struct input_device_id *id)
573 for (minor = 0; minor < TSDEV_MINORS / 2; minor++)
574 if (!tsdev_table[minor])
577 if (minor == TSDEV_MINORS) {
578 printk(KERN_ERR "tsdev: no more free tsdev devices\n");
582 tsdev = kzalloc(sizeof(struct tsdev), GFP_KERNEL);
586 INIT_LIST_HEAD(&tsdev->client_list);
587 spin_lock_init(&tsdev->client_lock);
588 mutex_init(&tsdev->mutex);
589 init_waitqueue_head(&tsdev->wait);
591 snprintf(tsdev->name, sizeof(tsdev->name), "ts%d", minor);
593 tsdev->minor = minor;
595 tsdev->handle.dev = dev;
596 tsdev->handle.name = tsdev->name;
597 tsdev->handle.handler = handler;
598 tsdev->handle.private = tsdev;
600 /* Precompute the rough calibration matrix */
601 delta = dev->absmax [ABS_X] - dev->absmin [ABS_X] + 1;
604 tsdev->cal.xscale = (xres << 8) / delta;
605 tsdev->cal.xtrans = - ((dev->absmin [ABS_X] * tsdev->cal.xscale) >> 8);
607 delta = dev->absmax [ABS_Y] - dev->absmin [ABS_Y] + 1;
610 tsdev->cal.yscale = (yres << 8) / delta;
611 tsdev->cal.ytrans = - ((dev->absmin [ABS_Y] * tsdev->cal.yscale) >> 8);
613 strlcpy(tsdev->dev.bus_id, tsdev->name, sizeof(tsdev->dev.bus_id));
614 tsdev->dev.devt = MKDEV(INPUT_MAJOR, TSDEV_MINOR_BASE + minor);
615 tsdev->dev.class = &input_class;
616 tsdev->dev.parent = &dev->dev;
617 tsdev->dev.release = tsdev_free;
618 device_initialize(&tsdev->dev);
620 error = input_register_handle(&tsdev->handle);
624 error = tsdev_install_chrdev(tsdev);
626 goto err_unregister_handle;
628 error = device_add(&tsdev->dev);
630 goto err_cleanup_tsdev;
635 tsdev_cleanup(tsdev);
636 err_unregister_handle:
637 input_unregister_handle(&tsdev->handle);
639 put_device(&tsdev->dev);
643 static void tsdev_disconnect(struct input_handle *handle)
645 struct tsdev *tsdev = handle->private;
647 device_del(&tsdev->dev);
648 tsdev_cleanup(tsdev);
649 input_unregister_handle(handle);
650 put_device(&tsdev->dev);
653 static const struct input_device_id tsdev_ids[] = {
655 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT | INPUT_DEVICE_ID_MATCH_RELBIT,
656 .evbit = { BIT(EV_KEY) | BIT(EV_REL) },
657 .keybit = { [LONG(BTN_LEFT)] = BIT(BTN_LEFT) },
658 .relbit = { BIT(REL_X) | BIT(REL_Y) },
659 }, /* A mouse like device, at least one button, two relative axes */
662 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
663 .evbit = { BIT(EV_KEY) | BIT(EV_ABS) },
664 .keybit = { [LONG(BTN_TOUCH)] = BIT(BTN_TOUCH) },
665 .absbit = { BIT(ABS_X) | BIT(ABS_Y) },
666 }, /* A tablet like device, at least touch detection, two absolute axes */
669 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
670 .evbit = { BIT(EV_ABS) },
671 .absbit = { BIT(ABS_X) | BIT(ABS_Y) | BIT(ABS_PRESSURE) },
672 }, /* A tablet like device with several gradations of pressure */
674 {} /* Terminating entry */
677 MODULE_DEVICE_TABLE(input, tsdev_ids);
679 static struct input_handler tsdev_handler = {
680 .event = tsdev_event,
681 .connect = tsdev_connect,
682 .disconnect = tsdev_disconnect,
684 .minor = TSDEV_MINOR_BASE,
686 .id_table = tsdev_ids,
689 static int __init tsdev_init(void)
691 return input_register_handler(&tsdev_handler);
694 static void __exit tsdev_exit(void)
696 input_unregister_handler(&tsdev_handler);
699 module_init(tsdev_init);
700 module_exit(tsdev_exit);