root/drivers/input/touchscreen/gunze.c

DEFINITIONS

1. gunze_process_packet
2. gunze_interrupt
3. gunze_disconnect
4. gunze_connect

   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 /*
  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     "Gunze AHL-51S touchscreen driver"
  21 
  22 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  23 MODULE_DESCRIPTION(DRIVER_DESC);
  24 MODULE_LICENSE("GPL");
  25 
  26 /*
  27  * Definitions & global arrays.
  28  */
  29 
  30 #define GUNZE_MAX_LENGTH        10
  31 
  32 /*
  33  * Per-touchscreen data.
  34  */
  35 
  36 struct gunze {
  37         struct input_dev *dev;
  38         struct serio *serio;
  39         int idx;
  40         unsigned char data[GUNZE_MAX_LENGTH];
  41         char phys[32];
  42 };
  43 
  44 static void gunze_process_packet(struct gunze *gunze)
  45 {
  46         struct input_dev *dev = gunze->dev;
  47 
  48         if (gunze->idx != GUNZE_MAX_LENGTH || gunze->data[5] != ',' ||
  49                 (gunze->data[0] != 'T' && gunze->data[0] != 'R')) {
  50                 printk(KERN_WARNING "gunze.c: bad packet: >%.*s<\n", GUNZE_MAX_LENGTH, gunze->data);
  51                 return;
  52         }
  53 
  54         input_report_abs(dev, ABS_X, simple_strtoul(gunze->data + 1, NULL, 10));
  55         input_report_abs(dev, ABS_Y, 1024 - simple_strtoul(gunze->data + 6, NULL, 10));
  56         input_report_key(dev, BTN_TOUCH, gunze->data[0] == 'T');
  57         input_sync(dev);
  58 }
  59 
  60 static irqreturn_t gunze_interrupt(struct serio *serio,
  61                 unsigned char data, unsigned int flags)
  62 {
  63         struct gunze *gunze = serio_get_drvdata(serio);
  64 
  65         if (data == '\r') {
  66                 gunze_process_packet(gunze);
  67                 gunze->idx = 0;
  68         } else {
  69                 if (gunze->idx < GUNZE_MAX_LENGTH)
  70                         gunze->data[gunze->idx++] = data;
  71         }
  72         return IRQ_HANDLED;
  73 }
  74 
  75 /*
  76  * gunze_disconnect() is the opposite of gunze_connect()
  77  */
  78 
  79 static void gunze_disconnect(struct serio *serio)
  80 {
  81         struct gunze *gunze = serio_get_drvdata(serio);
  82 
  83         input_get_device(gunze->dev);
  84         input_unregister_device(gunze->dev);
  85         serio_close(serio);
  86         serio_set_drvdata(serio, NULL);
  87         input_put_device(gunze->dev);
  88         kfree(gunze);
  89 }
  90 
  91 /*
  92  * gunze_connect() is the routine that is called when someone adds a
  93  * new serio device that supports Gunze protocol and registers it as
  94  * an input device.
  95  */
  96 
  97 static int gunze_connect(struct serio *serio, struct serio_driver *drv)
  98 {
  99         struct gunze *gunze;
 100         struct input_dev *input_dev;
 101         int err;
 102 
 103         gunze = kzalloc(sizeof(struct gunze), GFP_KERNEL);
 104         input_dev = input_allocate_device();
 105         if (!gunze || !input_dev) {
 106                 err = -ENOMEM;
 107                 goto fail1;
 108         }
 109 
 110         gunze->serio = serio;
 111         gunze->dev = input_dev;
 112         snprintf(gunze->phys, sizeof(serio->phys), "%s/input0", serio->phys);
 113 
 114         input_dev->name = "Gunze AHL-51S TouchScreen";
 115         input_dev->phys = gunze->phys;
 116         input_dev->id.bustype = BUS_RS232;
 117         input_dev->id.vendor = SERIO_GUNZE;
 118         input_dev->id.product = 0x0051;
 119         input_dev->id.version = 0x0100;
 120         input_dev->dev.parent = &serio->dev;
 121         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 122         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 123         input_set_abs_params(input_dev, ABS_X, 24, 1000, 0, 0);
 124         input_set_abs_params(input_dev, ABS_Y, 24, 1000, 0, 0);
 125 
 126         serio_set_drvdata(serio, gunze);
 127 
 128         err = serio_open(serio, drv);
 129         if (err)
 130                 goto fail2;
 131 
 132         err = input_register_device(gunze->dev);
 133         if (err)
 134                 goto fail3;
 135 
 136         return 0;
 137 
 138  fail3: serio_close(serio);
 139  fail2: serio_set_drvdata(serio, NULL);
 140  fail1: input_free_device(input_dev);
 141         kfree(gunze);
 142         return err;
 143 }
 144 
 145 /*
 146  * The serio driver structure.
 147  */
 148 
 149 static const struct serio_device_id gunze_serio_ids[] = {
 150         {
 151                 .type   = SERIO_RS232,
 152                 .proto  = SERIO_GUNZE,
 153                 .id     = SERIO_ANY,
 154                 .extra  = SERIO_ANY,
 155         },
 156         { 0 }
 157 };
 158 
 159 MODULE_DEVICE_TABLE(serio, gunze_serio_ids);
 160 
 161 static struct serio_driver gunze_drv = {
 162         .driver         = {
 163                 .name   = "gunze",
 164         },
 165         .description    = DRIVER_DESC,
 166         .id_table       = gunze_serio_ids,
 167         .interrupt      = gunze_interrupt,
 168         .connect        = gunze_connect,
 169         .disconnect     = gunze_disconnect,
 170 };
 171 
 172 module_serio_driver(gunze_drv);