LXR linux/drivers/input/touchscreen/touchright.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Touchright serial touchscreen driver
   4 *
   5 * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
   6 *
   7 * Based on MicroTouch driver (drivers/input/touchscreen/mtouch.c)
   8 * Copyright (c) 2004 Vojtech Pavlik
   9 * and Dan Streetman <ddstreet@ieee.org>
  10 */
  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
  20#define DRIVER_DESC     "Touchright serial touchscreen driver"
  21
  22MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
  23MODULE_DESCRIPTION(DRIVER_DESC);
  24MODULE_LICENSE("GPL");
  25
  26/*
  27 * Definitions & global arrays.
  28 */
  29
  30#define TR_FORMAT_TOUCH_BIT     0x01
  31#define TR_FORMAT_STATUS_BYTE   0x40
  32#define TR_FORMAT_STATUS_MASK   ~TR_FORMAT_TOUCH_BIT
  33
  34#define TR_LENGTH 5
  35
  36#define TR_MIN_XC 0
  37#define TR_MAX_XC 0x1ff
  38#define TR_MIN_YC 0
  39#define TR_MAX_YC 0x1ff
  40
  41/*
  42 * Per-touchscreen data.
  43 */
  44
  45struct tr {
  46        struct input_dev *dev;
  47        struct serio *serio;
  48        int idx;
  49        unsigned char data[TR_LENGTH];
  50        char phys[32];
  51};
  52
  53static irqreturn_t tr_interrupt(struct serio *serio,
  54                unsigned char data, unsigned int flags)
  55{
  56        struct tr *tr = serio_get_drvdata(serio);
  57        struct input_dev *dev = tr->dev;
  58
  59        tr->data[tr->idx] = data;
  60
  61        if ((tr->data[0] & TR_FORMAT_STATUS_MASK) == TR_FORMAT_STATUS_BYTE) {
  62                if (++tr->idx == TR_LENGTH) {
  63                        input_report_abs(dev, ABS_X,
  64                                (tr->data[1] << 5) | (tr->data[2] >> 1));
  65                        input_report_abs(dev, ABS_Y,
  66                                (tr->data[3] << 5) | (tr->data[4] >> 1));
  67                        input_report_key(dev, BTN_TOUCH,
  68                                tr->data[0] & TR_FORMAT_TOUCH_BIT);
  69                        input_sync(dev);
  70                        tr->idx = 0;
  71                }
  72        }
  73
  74        return IRQ_HANDLED;
  75}
  76
  77/*
  78 * tr_disconnect() is the opposite of tr_connect()
  79 */
  80
  81static void tr_disconnect(struct serio *serio)
  82{
  83        struct tr *tr = serio_get_drvdata(serio);
  84
  85        input_get_device(tr->dev);
  86        input_unregister_device(tr->dev);
  87        serio_close(serio);
  88        serio_set_drvdata(serio, NULL);
  89        input_put_device(tr->dev);
  90        kfree(tr);
  91}
  92
  93/*
  94 * tr_connect() is the routine that is called when someone adds a
  95 * new serio device that supports the Touchright protocol and registers it as
  96 * an input device.
  97 */
  98
  99static int tr_connect(struct serio *serio, struct serio_driver *drv)
 100{
 101        struct tr *tr;
 102        struct input_dev *input_dev;
 103        int err;
 104
 105        tr = kzalloc(sizeof(struct tr), GFP_KERNEL);
 106        input_dev = input_allocate_device();
 107        if (!tr || !input_dev) {
 108                err = -ENOMEM;
 109                goto fail1;
 110        }
 111
 112        tr->serio = serio;
 113        tr->dev = input_dev;
 114        snprintf(tr->phys, sizeof(tr->phys), "%s/input0", serio->phys);
 115
 116        input_dev->name = "Touchright Serial TouchScreen";
 117        input_dev->phys = tr->phys;
 118        input_dev->id.bustype = BUS_RS232;
 119        input_dev->id.vendor = SERIO_TOUCHRIGHT;
 120        input_dev->id.product = 0;
 121        input_dev->id.version = 0x0100;
 122        input_dev->dev.parent = &serio->dev;
 123        input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 124        input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 125        input_set_abs_params(tr->dev, ABS_X, TR_MIN_XC, TR_MAX_XC, 0, 0);
 126        input_set_abs_params(tr->dev, ABS_Y, TR_MIN_YC, TR_MAX_YC, 0, 0);
 127
 128        serio_set_drvdata(serio, tr);
 129
 130        err = serio_open(serio, drv);
 131        if (err)
 132                goto fail2;
 133
 134        err = input_register_device(tr->dev);
 135        if (err)
 136                goto fail3;
 137
 138        return 0;
 139
 140 fail3: serio_close(serio);
 141 fail2: serio_set_drvdata(serio, NULL);
 142 fail1: input_free_device(input_dev);
 143        kfree(tr);
 144        return err;
 145}
 146
 147/*
 148 * The serio driver structure.
 149 */
 150
 151static const struct serio_device_id tr_serio_ids[] = {
 152        {
 153                .type   = SERIO_RS232,
 154                .proto  = SERIO_TOUCHRIGHT,
 155                .id     = SERIO_ANY,
 156                .extra  = SERIO_ANY,
 157        },
 158        { 0 }
 159};
 160
 161MODULE_DEVICE_TABLE(serio, tr_serio_ids);
 162
 163static struct serio_driver tr_drv = {
 164        .driver         = {
 165                .name   = "touchright",
 166        },
 167        .description    = DRIVER_DESC,
 168        .id_table       = tr_serio_ids,
 169        .interrupt      = tr_interrupt,
 170        .connect        = tr_connect,
 171        .disconnect     = tr_disconnect,
 172};
 173
 174module_serio_driver(tr_drv);
 175