1/* 2 * Wacom W8001 penabled serial touchscreen driver 3 * 4 * Copyright (c) 2008 Jaya Kumar 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file COPYING in the main directory of this archive for 8 * more details. 9 * 10 * Layout based on Elo serial touchscreen driver by Vojtech Pavlik 11 */ 12 13#include <linux/errno.h> 14#include <linux/kernel.h> 15#include <linux/module.h> 16#include <linux/slab.h> 17#include <linux/input.h> 18#include <linux/serio.h> 19#include <linux/init.h> 20#include <linux/ctype.h> 21 22#define DRIVER_DESC "Wacom W8001 serial touchscreen driver" 23 24MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>"); 25MODULE_DESCRIPTION(DRIVER_DESC); 26MODULE_LICENSE("GPL"); 27 28#define W8001_MAX_LENGTH 11 29#define W8001_LEAD_MASK 0x80 30#define W8001_LEAD_BYTE 0x80 31#define W8001_TAB_MASK 0x40 32#define W8001_TAB_BYTE 0x40 33 34#define W8001_QUERY_PACKET 0x20 35 36#define W8001_CMD_START '1' 37#define W8001_CMD_QUERY '*' 38 39struct w8001_coord { 40 u8 rdy; 41 u8 tsw; 42 u8 f1; 43 u8 f2; 44 u16 x; 45 u16 y; 46 u16 pen_pressure; 47 u8 tilt_x; 48 u8 tilt_y; 49}; 50 51/* 52 * Per-touchscreen data. 53 */ 54 55struct w8001 { 56 struct input_dev *dev; 57 struct serio *serio; 58 struct completion cmd_done; 59 int id; 60 int idx; 61 unsigned char response_type; 62 unsigned char response[W8001_MAX_LENGTH]; 63 unsigned char data[W8001_MAX_LENGTH]; 64 char phys[32]; 65}; 66 67static void parse_data(u8 *data, struct w8001_coord *coord) 68{ 69 memset(coord, 0, sizeof(*coord)); 70 71 coord->rdy = data[0] & 0x20; 72 coord->tsw = data[0] & 0x01; 73 coord->f1 = data[0] & 0x02; 74 coord->f2 = data[0] & 0x04; 75 76 coord->x = (data[1] & 0x7F) << 9; 77 coord->x |= (data[2] & 0x7F) << 2; 78 coord->x |= (data[6] & 0x60) >> 5; 79 80 coord->y = (data[3] & 0x7F) << 9; 81 coord->y |= (data[4] & 0x7F) << 2; 82 coord->y |= (data[6] & 0x18) >> 3; 83 84 coord->pen_pressure = data[5] & 0x7F; 85 coord->pen_pressure |= (data[6] & 0x07) << 7 ; 86 87 coord->tilt_x = data[7] & 0x7F; 88 coord->tilt_y = data[8] & 0x7F; 89} 90 91static irqreturn_t w8001_interrupt(struct serio *serio, 92 unsigned char data, unsigned int flags) 93{ 94 struct w8001 *w8001 = serio_get_drvdata(serio); 95 struct input_dev *dev = w8001->dev; 96 struct w8001_coord coord; 97 unsigned char tmp; 98 99 w8001->data[w8001->idx] = data; 100 switch (w8001->idx++) { 101 case 0: 102 if ((data & W8001_LEAD_MASK) != W8001_LEAD_BYTE) { 103 pr_debug("w8001: unsynchronized data: 0x%02x\n", data); 104 w8001->idx = 0; 105 } 106 break; 107 108 case 8: 109 tmp = w8001->data[0] & W8001_TAB_MASK; 110 if (unlikely(tmp == W8001_TAB_BYTE)) 111 break; 112 113 w8001->idx = 0; 114 parse_data(w8001->data, &coord); 115 input_report_abs(dev, ABS_X, coord.x); 116 input_report_abs(dev, ABS_Y, coord.y); 117 input_report_abs(dev, ABS_PRESSURE, coord.pen_pressure); 118 input_report_key(dev, BTN_TOUCH, coord.tsw); 119 input_sync(dev); 120 break; 121 122 case 10: 123 w8001->idx = 0; 124 memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH); 125 w8001->response_type = W8001_QUERY_PACKET; 126 complete(&w8001->cmd_done); 127 break; 128 } 129 130 return IRQ_HANDLED; 131} 132 133static int w8001_command(struct w8001 *w8001, unsigned char command, 134 bool wait_response) 135{ 136 int rc; 137 138 w8001->response_type = 0; 139 init_completion(&w8001->cmd_done); 140 141 rc = serio_write(w8001->serio, command); 142 if (rc == 0 && wait_response) { 143 144 wait_for_completion_timeout(&w8001->cmd_done, HZ); 145 if (w8001->response_type != W8001_QUERY_PACKET) 146 rc = -EIO; 147 } 148 149 return rc; 150} 151 152static int w8001_setup(struct w8001 *w8001) 153{ 154 struct input_dev *dev = w8001->dev; 155 struct w8001_coord coord; 156 int error; 157 158 error = w8001_command(w8001, W8001_CMD_QUERY, true); 159 if (error) 160 return error; 161 162 parse_data(w8001->response, &coord); 163 164 input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0); 165 input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0); 166 input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0); 167 input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0); 168 input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0); 169 170 return w8001_command(w8001, W8001_CMD_START, false); 171} 172 173/* 174 * w8001_disconnect() is the opposite of w8001_connect() 175 */ 176 177static void w8001_disconnect(struct serio *serio) 178{ 179 struct w8001 *w8001 = serio_get_drvdata(serio); 180 181 input_get_device(w8001->dev); 182 input_unregister_device(w8001->dev); 183 serio_close(serio); 184 serio_set_drvdata(serio, NULL); 185 input_put_device(w8001->dev); 186 kfree(w8001); 187} 188 189/* 190 * w8001_connect() is the routine that is called when someone adds a 191 * new serio device that supports the w8001 protocol and registers it as 192 * an input device. 193 */ 194 195static int w8001_connect(struct serio *serio, struct serio_driver *drv) 196{ 197 struct w8001 *w8001; 198 struct input_dev *input_dev; 199 int err; 200 201 w8001 = kzalloc(sizeof(struct w8001), GFP_KERNEL); 202 input_dev = input_allocate_device(); 203 if (!w8001 || !input_dev) { 204 err = -ENOMEM; 205 goto fail1; 206 } 207 208 w8001->serio = serio; 209 w8001->id = serio->id.id; 210 w8001->dev = input_dev; 211 init_completion(&w8001->cmd_done); 212 snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys); 213 214 input_dev->name = "Wacom W8001 Penabled Serial TouchScreen"; 215 input_dev->phys = w8001->phys; 216 input_dev->id.bustype = BUS_RS232; 217 input_dev->id.vendor = SERIO_W8001; 218 input_dev->id.product = w8001->id; 219 input_dev->id.version = 0x0100; 220 input_dev->dev.parent = &serio->dev; 221 222 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); 223 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); 224 225 serio_set_drvdata(serio, w8001); 226 err = serio_open(serio, drv); 227 if (err) 228 goto fail2; 229 230 err = w8001_setup(w8001); 231 if (err) 232 goto fail3; 233 234 err = input_register_device(w8001->dev); 235 if (err) 236 goto fail3; 237 238 return 0; 239 240fail3: 241 serio_close(serio); 242fail2: 243 serio_set_drvdata(serio, NULL); 244fail1: 245 input_free_device(input_dev); 246 kfree(w8001); 247 return err; 248} 249 250static struct serio_device_id w8001_serio_ids[] = { 251 { 252 .type = SERIO_RS232, 253 .proto = SERIO_W8001, 254 .id = SERIO_ANY, 255 .extra = SERIO_ANY, 256 }, 257 { 0 } 258}; 259 260MODULE_DEVICE_TABLE(serio, w8001_serio_ids); 261 262static struct serio_driver w8001_drv = { 263 .driver = { 264 .name = "w8001", 265 }, 266 .description = DRIVER_DESC, 267 .id_table = w8001_serio_ids, 268 .interrupt = w8001_interrupt, 269 .connect = w8001_connect, 270 .disconnect = w8001_disconnect, 271}; 272 273static int __init w8001_init(void) 274{ 275 return serio_register_driver(&w8001_drv); 276} 277 278static void __exit w8001_exit(void) 279{ 280 serio_unregister_driver(&w8001_drv); 281} 282 283module_init(w8001_init); 284module_exit(w8001_exit); 285