input/touchscreen/touchright.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Touchright serial touchscreen driver
0004  *
0005  * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
0006  *
0007  * Based on MicroTouch driver (drivers/input/touchscreen/mtouch.c)
0008  * Copyright (c) 2004 Vojtech Pavlik
0009  * and Dan Streetman <ddstreet@ieee.org>
0010  */
0011
0012
0013 #include <linux/errno.h>
0014 #include <linux/kernel.h>
0015 #include <linux/module.h>
0016 #include <linux/slab.h>
0017 #include <linux/input.h>
0018 #include <linux/serio.h>
0019
0020 #define DRIVER_DESC "Touchright serial touchscreen driver"
0021
0022 MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
0023 MODULE_DESCRIPTION(DRIVER_DESC);
0024 MODULE_LICENSE("GPL");
0025
0026 /*
0027  * Definitions & global arrays.
0028  */
0029
0030 #define TR_FORMAT_TOUCH_BIT 0x01
0031 #define TR_FORMAT_STATUS_BYTE   0x40
0032 #define TR_FORMAT_STATUS_MASK   ~TR_FORMAT_TOUCH_BIT
0033
0034 #define TR_LENGTH 5
0035
0036 #define TR_MIN_XC 0
0037 #define TR_MAX_XC 0x1ff
0038 #define TR_MIN_YC 0
0039 #define TR_MAX_YC 0x1ff
0040
0041 /*
0042  * Per-touchscreen data.
0043  */
0044
0045 struct tr {
0046     struct input_dev *dev;
0047     struct serio *serio;
0048     int idx;
0049     unsigned char data[TR_LENGTH];
0050     char phys[32];
0051 };
0052
0053 static irqreturn_t tr_interrupt(struct serio *serio,
0054         unsigned char data, unsigned int flags)
0055 {
0056     struct tr *tr = serio_get_drvdata(serio);
0057     struct input_dev *dev = tr->dev;
0058
0059     tr->data[tr->idx] = data;
0060
0061     if ((tr->data[0] & TR_FORMAT_STATUS_MASK) == TR_FORMAT_STATUS_BYTE) {
0062         if (++tr->idx == TR_LENGTH) {
0063             input_report_abs(dev, ABS_X,
0064                 (tr->data[1] << 5) | (tr->data[2] >> 1));
0065             input_report_abs(dev, ABS_Y,
0066                 (tr->data[3] << 5) | (tr->data[4] >> 1));
0067             input_report_key(dev, BTN_TOUCH,
0068                 tr->data[0] & TR_FORMAT_TOUCH_BIT);
0069             input_sync(dev);
0070             tr->idx = 0;
0071         }
0072     }
0073
0074     return IRQ_HANDLED;
0075 }
0076
0077 /*
0078  * tr_disconnect() is the opposite of tr_connect()
0079  */
0080
0081 static void tr_disconnect(struct serio *serio)
0082 {
0083     struct tr *tr = serio_get_drvdata(serio);
0084
0085     input_get_device(tr->dev);
0086     input_unregister_device(tr->dev);
0087     serio_close(serio);
0088     serio_set_drvdata(serio, NULL);
0089     input_put_device(tr->dev);
0090     kfree(tr);
0091 }
0092
0093 /*
0094  * tr_connect() is the routine that is called when someone adds a
0095  * new serio device that supports the Touchright protocol and registers it as
0096  * an input device.
0097  */
0098
0099 static int tr_connect(struct serio *serio, struct serio_driver *drv)
0100 {
0101     struct tr *tr;
0102     struct input_dev *input_dev;
0103     int err;
0104
0105     tr = kzalloc(sizeof(struct tr), GFP_KERNEL);
0106     input_dev = input_allocate_device();
0107     if (!tr || !input_dev) {
0108         err = -ENOMEM;
0109         goto fail1;
0110     }
0111
0112     tr->serio = serio;
0113     tr->dev = input_dev;
0114     snprintf(tr->phys, sizeof(tr->phys), "%s/input0", serio->phys);
0115
0116     input_dev->name = "Touchright Serial TouchScreen";
0117     input_dev->phys = tr->phys;
0118     input_dev->id.bustype = BUS_RS232;
0119     input_dev->id.vendor = SERIO_TOUCHRIGHT;
0120     input_dev->id.product = 0;
0121     input_dev->id.version = 0x0100;
0122     input_dev->dev.parent = &serio->dev;
0123     input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
0124     input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
0125     input_set_abs_params(tr->dev, ABS_X, TR_MIN_XC, TR_MAX_XC, 0, 0);
0126     input_set_abs_params(tr->dev, ABS_Y, TR_MIN_YC, TR_MAX_YC, 0, 0);
0127
0128     serio_set_drvdata(serio, tr);
0129
0130     err = serio_open(serio, drv);
0131     if (err)
0132         goto fail2;
0133
0134     err = input_register_device(tr->dev);
0135     if (err)
0136         goto fail3;
0137
0138     return 0;
0139
0140  fail3: serio_close(serio);
0141  fail2: serio_set_drvdata(serio, NULL);
0142  fail1: input_free_device(input_dev);
0143     kfree(tr);
0144     return err;
0145 }
0146
0147 /*
0148  * The serio driver structure.
0149  */
0150
0151 static const struct serio_device_id tr_serio_ids[] = {
0152     {
0153         .type   = SERIO_RS232,
0154         .proto  = SERIO_TOUCHRIGHT,
0155         .id = SERIO_ANY,
0156         .extra  = SERIO_ANY,
0157     },
0158     { 0 }
0159 };
0160
0161 MODULE_DEVICE_TABLE(serio, tr_serio_ids);
0162
0163 static struct serio_driver tr_drv = {
0164     .driver     = {
0165         .name   = "touchright",
0166     },
0167     .description    = DRIVER_DESC,
0168     .id_table   = tr_serio_ids,
0169     .interrupt  = tr_interrupt,
0170     .connect    = tr_connect,
0171     .disconnect = tr_disconnect,
0172 };
0173
0174 module_serio_driver(tr_drv);