drivers/input/touchscreen/gunze.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (c) 2000-2001 Vojtech Pavlik
   4  */
   5
   6 /*
   7  * Gunze AHL-51S touchscreen driver for Linux
   8  */
   9
  10 #include <linux/errno.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/input.h>
  15 #include <linux/serio.h>
  16
  17 #define DRIVER_DESC     "Gunze AHL-51S touchscreen driver"
  18
  19 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  20 MODULE_DESCRIPTION(DRIVER_DESC);
  21 MODULE_LICENSE("GPL");
  22
  23 /*
  24  * Definitions & global arrays.
  25  */
  26
  27 #define GUNZE_MAX_LENGTH        10
  28
  29 /*
  30  * Per-touchscreen data.
  31  */
  32
  33 struct gunze {
  34         struct input_dev *dev;
  35         struct serio *serio;
  36         int idx;
  37         unsigned char data[GUNZE_MAX_LENGTH];
  38         char phys[32];
  39 };
  40
  41 static void gunze_process_packet(struct gunze *gunze)
  42 {
  43         struct input_dev *dev = gunze->dev;
  44
  45         if (gunze->idx != GUNZE_MAX_LENGTH || gunze->data[5] != ',' ||
  46                 (gunze->data[0] != 'T' && gunze->data[0] != 'R')) {
  47                 printk(KERN_WARNING "gunze.c: bad packet: >%.*s<\n", GUNZE_MAX_LENGTH, gunze->data);
  48                 return;
  49         }
  50
  51         input_report_abs(dev, ABS_X, simple_strtoul(gunze->data + 1, NULL, 10));
  52         input_report_abs(dev, ABS_Y, 1024 - simple_strtoul(gunze->data + 6, NULL, 10));
  53         input_report_key(dev, BTN_TOUCH, gunze->data[0] == 'T');
  54         input_sync(dev);
  55 }
  56
  57 static irqreturn_t gunze_interrupt(struct serio *serio,
  58                 unsigned char data, unsigned int flags)
  59 {
  60         struct gunze *gunze = serio_get_drvdata(serio);
  61
  62         if (data == '\r') {
  63                 gunze_process_packet(gunze);
  64                 gunze->idx = 0;
  65         } else {
  66                 if (gunze->idx < GUNZE_MAX_LENGTH)
  67                         gunze->data[gunze->idx++] = data;
  68         }
  69         return IRQ_HANDLED;
  70 }
  71
  72 /*
  73  * gunze_disconnect() is the opposite of gunze_connect()
  74  */
  75
  76 static void gunze_disconnect(struct serio *serio)
  77 {
  78         struct gunze *gunze = serio_get_drvdata(serio);
  79
  80         input_get_device(gunze->dev);
  81         input_unregister_device(gunze->dev);
  82         serio_close(serio);
  83         serio_set_drvdata(serio, NULL);
  84         input_put_device(gunze->dev);
  85         kfree(gunze);
  86 }
  87
  88 /*
  89  * gunze_connect() is the routine that is called when someone adds a
  90  * new serio device that supports Gunze protocol and registers it as
  91  * an input device.
  92  */
  93
  94 static int gunze_connect(struct serio *serio, struct serio_driver *drv)
  95 {
  96         struct gunze *gunze;
  97         struct input_dev *input_dev;
  98         int err;
  99
 100         gunze = kzalloc(sizeof(*gunze), GFP_KERNEL);
 101         input_dev = input_allocate_device();
 102         if (!gunze || !input_dev) {
 103                 err = -ENOMEM;
 104                 goto fail1;
 105         }
 106
 107         gunze->serio = serio;
 108         gunze->dev = input_dev;
 109         snprintf(gunze->phys, sizeof(serio->phys), "%s/input0", serio->phys);
 110
 111         input_dev->name = "Gunze AHL-51S TouchScreen";
 112         input_dev->phys = gunze->phys;
 113         input_dev->id.bustype = BUS_RS232;
 114         input_dev->id.vendor = SERIO_GUNZE;
 115         input_dev->id.product = 0x0051;
 116         input_dev->id.version = 0x0100;
 117         input_dev->dev.parent = &serio->dev;
 118         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 119         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 120         input_set_abs_params(input_dev, ABS_X, 24, 1000, 0, 0);
 121         input_set_abs_params(input_dev, ABS_Y, 24, 1000, 0, 0);
 122
 123         serio_set_drvdata(serio, gunze);
 124
 125         err = serio_open(serio, drv);
 126         if (err)
 127                 goto fail2;
 128
 129         err = input_register_device(gunze->dev);
 130         if (err)
 131                 goto fail3;
 132
 133         return 0;
 134
 135  fail3: serio_close(serio);
 136  fail2: serio_set_drvdata(serio, NULL);
 137  fail1: input_free_device(input_dev);
 138         kfree(gunze);
 139         return err;
 140 }
 141
 142 /*
 143  * The serio driver structure.
 144  */
 145
 146 static const struct serio_device_id gunze_serio_ids[] = {
 147         {
 148                 .type   = SERIO_RS232,
 149                 .proto  = SERIO_GUNZE,
 150                 .id     = SERIO_ANY,
 151                 .extra  = SERIO_ANY,
 152         },
 153         { 0 }
 154 };
 155
 156 MODULE_DEVICE_TABLE(serio, gunze_serio_ids);
 157
 158 static struct serio_driver gunze_drv = {
 159         .driver         = {
 160                 .name   = "gunze",
 161         },
 162         .description    = DRIVER_DESC,
 163         .id_table       = gunze_serio_ids,
 164         .interrupt      = gunze_interrupt,
 165         .connect        = gunze_connect,
 166         .disconnect     = gunze_disconnect,
 167 };
 168
 169 module_serio_driver(gunze_drv);