2 * Wacom W8001 penabled serial touchscreen driver
4 * Copyright (c) 2008 Jaya Kumar
5 * Copyright (c) 2010 Red Hat, Inc.
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License. See the file COPYING in the main directory of this archive for
11 * Layout based on Elo serial touchscreen driver by Vojtech Pavlik
14 #include <linux/errno.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/input/mt.h>
19 #include <linux/serio.h>
20 #include <linux/init.h>
21 #include <linux/ctype.h>
22 #include <linux/delay.h>
24 #define DRIVER_DESC "Wacom W8001 serial touchscreen driver"
26 MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>");
27 MODULE_DESCRIPTION(DRIVER_DESC);
28 MODULE_LICENSE("GPL");
30 #define W8001_MAX_LENGTH 11
31 #define W8001_LEAD_MASK 0x80
32 #define W8001_LEAD_BYTE 0x80
33 #define W8001_TAB_MASK 0x40
34 #define W8001_TAB_BYTE 0x40
35 /* set in first byte of touch data packets */
36 #define W8001_TOUCH_MASK (0x10 | W8001_LEAD_MASK)
37 #define W8001_TOUCH_BYTE (0x10 | W8001_LEAD_BYTE)
39 #define W8001_QUERY_PACKET 0x20
41 #define W8001_CMD_STOP '0'
42 #define W8001_CMD_START '1'
43 #define W8001_CMD_QUERY '*'
44 #define W8001_CMD_TOUCHQUERY '%'
46 /* length of data packets in bytes, depends on device. */
47 #define W8001_PKTLEN_TOUCH93 5
48 #define W8001_PKTLEN_TOUCH9A 7
49 #define W8001_PKTLEN_TPCPEN 9
50 #define W8001_PKTLEN_TPCCTL 11 /* control packet */
51 #define W8001_PKTLEN_TOUCH2FG 13
65 /* touch query reply packet */
66 struct w8001_touch_query {
75 * Per-touchscreen data.
79 struct input_dev *dev;
81 struct completion cmd_done;
84 unsigned char response_type;
85 unsigned char response[W8001_MAX_LENGTH];
86 unsigned char data[W8001_MAX_LENGTH];
92 static void parse_data(u8 *data, struct w8001_coord *coord)
94 memset(coord, 0, sizeof(*coord));
96 coord->rdy = data[0] & 0x20;
97 coord->tsw = data[0] & 0x01;
98 coord->f1 = data[0] & 0x02;
99 coord->f2 = data[0] & 0x04;
101 coord->x = (data[1] & 0x7F) << 9;
102 coord->x |= (data[2] & 0x7F) << 2;
103 coord->x |= (data[6] & 0x60) >> 5;
105 coord->y = (data[3] & 0x7F) << 9;
106 coord->y |= (data[4] & 0x7F) << 2;
107 coord->y |= (data[6] & 0x18) >> 3;
109 coord->pen_pressure = data[5] & 0x7F;
110 coord->pen_pressure |= (data[6] & 0x07) << 7 ;
112 coord->tilt_x = data[7] & 0x7F;
113 coord->tilt_y = data[8] & 0x7F;
116 static void parse_touch(struct w8001 *w8001)
118 struct input_dev *dev = w8001->dev;
119 unsigned char *data = w8001->data;
122 for (i = 0; i < 2; i++) {
123 bool touch = data[0] & (1 << i);
125 input_mt_slot(dev, i);
126 input_mt_report_slot_state(dev, MT_TOOL_FINGER, touch);
128 int x = (data[6 * i + 1] << 7) | (data[6 * i + 2]);
129 int y = (data[6 * i + 3] << 7) | (data[6 * i + 4]);
130 /* data[5,6] and [11,12] is finger capacity */
132 input_report_abs(dev, ABS_MT_POSITION_X, x);
133 input_report_abs(dev, ABS_MT_POSITION_Y, y);
140 static void parse_touchquery(u8 *data, struct w8001_touch_query *query)
142 memset(query, 0, sizeof(*query));
144 query->panel_res = data[1];
145 query->sensor_id = data[2] & 0x7;
146 query->capacity_res = data[7];
148 query->x = data[3] << 9;
149 query->x |= data[4] << 2;
150 query->x |= (data[2] >> 5) & 0x3;
152 query->y = data[5] << 9;
153 query->y |= data[6] << 2;
154 query->y |= (data[2] >> 3) & 0x3;
157 static void report_pen_events(struct w8001 *w8001, struct w8001_coord *coord)
159 struct input_dev *dev = w8001->dev;
162 * We have 1 bit for proximity (rdy) and 3 bits for tip, side,
163 * side2/eraser. If rdy && f2 are set, this can be either pen + side2,
165 * - if dev is already in proximity and f2 is toggled → pen + side2
166 * - if dev comes into proximity with f2 set → eraser
167 * If f2 disappears after assuming eraser, fake proximity out for
168 * eraser and in for pen.
172 w8001->type = coord->f2 ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
173 } else if (w8001->type == BTN_TOOL_RUBBER) {
175 input_report_abs(dev, ABS_PRESSURE, 0);
176 input_report_key(dev, BTN_TOUCH, 0);
177 input_report_key(dev, BTN_STYLUS, 0);
178 input_report_key(dev, BTN_STYLUS2, 0);
179 input_report_key(dev, BTN_TOOL_RUBBER, 0);
181 w8001->type = BTN_TOOL_PEN;
184 input_report_key(dev, BTN_STYLUS2, coord->f2);
187 input_report_abs(dev, ABS_X, coord->x);
188 input_report_abs(dev, ABS_Y, coord->y);
189 input_report_abs(dev, ABS_PRESSURE, coord->pen_pressure);
190 input_report_key(dev, BTN_TOUCH, coord->tsw);
191 input_report_key(dev, BTN_STYLUS, coord->f1);
192 input_report_key(dev, w8001->type, coord->rdy);
199 static irqreturn_t w8001_interrupt(struct serio *serio,
200 unsigned char data, unsigned int flags)
202 struct w8001 *w8001 = serio_get_drvdata(serio);
203 struct w8001_coord coord;
206 w8001->data[w8001->idx] = data;
207 switch (w8001->idx++) {
209 if ((data & W8001_LEAD_MASK) != W8001_LEAD_BYTE) {
210 pr_debug("w8001: unsynchronized data: 0x%02x\n", data);
215 case W8001_PKTLEN_TOUCH93 - 1:
216 case W8001_PKTLEN_TOUCH9A - 1:
217 /* ignore one-finger touch packet. */
218 if (w8001->pktlen == w8001->idx)
222 /* Pen coordinates packet */
223 case W8001_PKTLEN_TPCPEN - 1:
224 tmp = w8001->data[0] & W8001_TAB_MASK;
225 if (unlikely(tmp == W8001_TAB_BYTE))
228 tmp = (w8001->data[0] & W8001_TOUCH_BYTE);
229 if (tmp == W8001_TOUCH_BYTE)
233 parse_data(w8001->data, &coord);
234 report_pen_events(w8001, &coord);
238 case W8001_PKTLEN_TPCCTL - 1:
239 tmp = (w8001->data[0] & W8001_TOUCH_MASK);
240 if (tmp == W8001_TOUCH_BYTE)
244 memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH);
245 w8001->response_type = W8001_QUERY_PACKET;
246 complete(&w8001->cmd_done);
249 /* 2 finger touch packet */
250 case W8001_PKTLEN_TOUCH2FG - 1:
259 static int w8001_command(struct w8001 *w8001, unsigned char command,
264 w8001->response_type = 0;
265 init_completion(&w8001->cmd_done);
267 rc = serio_write(w8001->serio, command);
268 if (rc == 0 && wait_response) {
270 wait_for_completion_timeout(&w8001->cmd_done, HZ);
271 if (w8001->response_type != W8001_QUERY_PACKET)
278 static int w8001_setup(struct w8001 *w8001)
280 struct input_dev *dev = w8001->dev;
281 struct w8001_coord coord;
284 error = w8001_command(w8001, W8001_CMD_STOP, false);
288 msleep(250); /* wait 250ms before querying the device */
291 error = w8001_command(w8001, W8001_CMD_QUERY, true);
293 __set_bit(BTN_TOOL_PEN, dev->keybit);
294 __set_bit(BTN_TOOL_RUBBER, dev->keybit);
295 __set_bit(BTN_STYLUS, dev->keybit);
296 __set_bit(BTN_STYLUS2, dev->keybit);
297 parse_data(w8001->response, &coord);
299 input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
300 input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
301 input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
302 if (coord.tilt_x && coord.tilt_y) {
303 input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
304 input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);
309 error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, true);
312 * Some non-touch devices may reply to the touch query. But their
313 * second byte is empty, which indicates touch is not supported.
315 if (!error && w8001->response[1]) {
316 struct w8001_touch_query touch;
318 parse_touchquery(w8001->response, &touch);
320 input_set_abs_params(dev, ABS_X, 0, touch.x, 0, 0);
321 input_set_abs_params(dev, ABS_Y, 0, touch.y, 0, 0);
322 __set_bit(BTN_TOOL_FINGER, dev->keybit);
324 switch (touch.sensor_id) {
327 w8001->pktlen = W8001_PKTLEN_TOUCH93;
332 w8001->pktlen = W8001_PKTLEN_TOUCH9A;
335 w8001->pktlen = W8001_PKTLEN_TOUCH2FG;
337 input_mt_init_slots(dev, 2);
338 input_set_abs_params(dev, ABS_MT_POSITION_X,
340 input_set_abs_params(dev, ABS_MT_POSITION_Y,
342 input_set_abs_params(dev, ABS_MT_TOOL_TYPE,
343 0, MT_TOOL_MAX, 0, 0);
348 return w8001_command(w8001, W8001_CMD_START, false);
352 * w8001_disconnect() is the opposite of w8001_connect()
355 static void w8001_disconnect(struct serio *serio)
357 struct w8001 *w8001 = serio_get_drvdata(serio);
359 input_get_device(w8001->dev);
360 input_unregister_device(w8001->dev);
362 serio_set_drvdata(serio, NULL);
363 input_put_device(w8001->dev);
368 * w8001_connect() is the routine that is called when someone adds a
369 * new serio device that supports the w8001 protocol and registers it as
373 static int w8001_connect(struct serio *serio, struct serio_driver *drv)
376 struct input_dev *input_dev;
379 w8001 = kzalloc(sizeof(struct w8001), GFP_KERNEL);
380 input_dev = input_allocate_device();
381 if (!w8001 || !input_dev) {
386 w8001->serio = serio;
387 w8001->id = serio->id.id;
388 w8001->dev = input_dev;
389 init_completion(&w8001->cmd_done);
390 snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys);
392 input_dev->name = "Wacom W8001 Penabled Serial TouchScreen";
393 input_dev->phys = w8001->phys;
394 input_dev->id.bustype = BUS_RS232;
395 input_dev->id.vendor = SERIO_W8001;
396 input_dev->id.product = w8001->id;
397 input_dev->id.version = 0x0100;
398 input_dev->dev.parent = &serio->dev;
400 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
401 __set_bit(BTN_TOUCH, input_dev->keybit);
403 serio_set_drvdata(serio, w8001);
404 err = serio_open(serio, drv);
408 err = w8001_setup(w8001);
412 err = input_register_device(w8001->dev);
421 serio_set_drvdata(serio, NULL);
423 input_free_device(input_dev);
428 static struct serio_device_id w8001_serio_ids[] = {
431 .proto = SERIO_W8001,
438 MODULE_DEVICE_TABLE(serio, w8001_serio_ids);
440 static struct serio_driver w8001_drv = {
444 .description = DRIVER_DESC,
445 .id_table = w8001_serio_ids,
446 .interrupt = w8001_interrupt,
447 .connect = w8001_connect,
448 .disconnect = w8001_disconnect,
451 static int __init w8001_init(void)
453 return serio_register_driver(&w8001_drv);
456 static void __exit w8001_exit(void)
458 serio_unregister_driver(&w8001_drv);
461 module_init(w8001_init);
462 module_exit(w8001_exit);