root/drivers/input/joystick/stinger.c

DEFINITIONS

1. stinger_process_packet
2. stinger_interrupt
3. stinger_disconnect
4. stinger_connect

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (c) 2000-2001 Vojtech Pavlik
   4  *  Copyright (c) 2000 Mark Fletcher
   5  */
   6 
   7 /*
   8  * Gravis Stinger gamepad driver for Linux
   9  */
  10 
  11 /*
  12  */
  13 
  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     "Gravis Stinger gamepad driver"
  21 
  22 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
  23 MODULE_DESCRIPTION(DRIVER_DESC);
  24 MODULE_LICENSE("GPL");
  25 
  26 /*
  27  * Constants.
  28  */
  29 
  30 #define STINGER_MAX_LENGTH 8
  31 
  32 /*
  33  * Per-Stinger data.
  34  */
  35 
  36 struct stinger {
  37         struct input_dev *dev;
  38         int idx;
  39         unsigned char data[STINGER_MAX_LENGTH];
  40         char phys[32];
  41 };
  42 
  43 /*
  44  * stinger_process_packet() decodes packets the driver receives from the
  45  * Stinger. It updates the data accordingly.
  46  */
  47 
  48 static void stinger_process_packet(struct stinger *stinger)
  49 {
  50         struct input_dev *dev = stinger->dev;
  51         unsigned char *data = stinger->data;
  52 
  53         if (!stinger->idx) return;
  54 
  55         input_report_key(dev, BTN_A,      ((data[0] & 0x20) >> 5));
  56         input_report_key(dev, BTN_B,      ((data[0] & 0x10) >> 4));
  57         input_report_key(dev, BTN_C,      ((data[0] & 0x08) >> 3));
  58         input_report_key(dev, BTN_X,      ((data[0] & 0x04) >> 2));
  59         input_report_key(dev, BTN_Y,      ((data[3] & 0x20) >> 5));
  60         input_report_key(dev, BTN_Z,      ((data[3] & 0x10) >> 4));
  61         input_report_key(dev, BTN_TL,     ((data[3] & 0x08) >> 3));
  62         input_report_key(dev, BTN_TR,     ((data[3] & 0x04) >> 2));
  63         input_report_key(dev, BTN_SELECT, ((data[3] & 0x02) >> 1));
  64         input_report_key(dev, BTN_START,   (data[3] & 0x01));
  65 
  66         input_report_abs(dev, ABS_X, (data[1] & 0x3F) - ((data[0] & 0x01) << 6));
  67         input_report_abs(dev, ABS_Y, ((data[0] & 0x02) << 5) - (data[2] & 0x3F));
  68 
  69         input_sync(dev);
  70 
  71         return;
  72 }
  73 
  74 /*
  75  * stinger_interrupt() is called by the low level driver when characters
  76  * are ready for us. We then buffer them for further processing, or call the
  77  * packet processing routine.
  78  */
  79 
  80 static irqreturn_t stinger_interrupt(struct serio *serio,
  81         unsigned char data, unsigned int flags)
  82 {
  83         struct stinger *stinger = serio_get_drvdata(serio);
  84 
  85         /* All Stinger packets are 4 bytes */
  86 
  87         if (stinger->idx < STINGER_MAX_LENGTH)
  88                 stinger->data[stinger->idx++] = data;
  89 
  90         if (stinger->idx == 4) {
  91                 stinger_process_packet(stinger);
  92                 stinger->idx = 0;
  93         }
  94 
  95         return IRQ_HANDLED;
  96 }
  97 
  98 /*
  99  * stinger_disconnect() is the opposite of stinger_connect()
 100  */
 101 
 102 static void stinger_disconnect(struct serio *serio)
 103 {
 104         struct stinger *stinger = serio_get_drvdata(serio);
 105 
 106         serio_close(serio);
 107         serio_set_drvdata(serio, NULL);
 108         input_unregister_device(stinger->dev);
 109         kfree(stinger);
 110 }
 111 
 112 /*
 113  * stinger_connect() is the routine that is called when someone adds a
 114  * new serio device that supports Stinger protocol and registers it as
 115  * an input device.
 116  */
 117 
 118 static int stinger_connect(struct serio *serio, struct serio_driver *drv)
 119 {
 120         struct stinger *stinger;
 121         struct input_dev *input_dev;
 122         int err = -ENOMEM;
 123 
 124         stinger = kmalloc(sizeof(struct stinger), GFP_KERNEL);
 125         input_dev = input_allocate_device();
 126         if (!stinger || !input_dev)
 127                 goto fail1;
 128 
 129         stinger->dev = input_dev;
 130         snprintf(stinger->phys, sizeof(stinger->phys), "%s/serio0", serio->phys);
 131 
 132         input_dev->name = "Gravis Stinger";
 133         input_dev->phys = stinger->phys;
 134         input_dev->id.bustype = BUS_RS232;
 135         input_dev->id.vendor = SERIO_STINGER;
 136         input_dev->id.product = 0x0001;
 137         input_dev->id.version = 0x0100;
 138         input_dev->dev.parent = &serio->dev;
 139 
 140         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 141         input_dev->keybit[BIT_WORD(BTN_A)] = BIT_MASK(BTN_A) | BIT_MASK(BTN_B) |
 142                 BIT_MASK(BTN_C) | BIT_MASK(BTN_X) | BIT_MASK(BTN_Y) |
 143                 BIT_MASK(BTN_Z) | BIT_MASK(BTN_TL) | BIT_MASK(BTN_TR) |
 144                 BIT_MASK(BTN_START) | BIT_MASK(BTN_SELECT);
 145         input_set_abs_params(input_dev, ABS_X, -64, 64, 0, 4);
 146         input_set_abs_params(input_dev, ABS_Y, -64, 64, 0, 4);
 147 
 148         serio_set_drvdata(serio, stinger);
 149 
 150         err = serio_open(serio, drv);
 151         if (err)
 152                 goto fail2;
 153 
 154         err = input_register_device(stinger->dev);
 155         if (err)
 156                 goto fail3;
 157 
 158         return 0;
 159 
 160  fail3: serio_close(serio);
 161  fail2: serio_set_drvdata(serio, NULL);
 162  fail1: input_free_device(input_dev);
 163         kfree(stinger);
 164         return err;
 165 }
 166 
 167 /*
 168  * The serio driver structure.
 169  */
 170 
 171 static const struct serio_device_id stinger_serio_ids[] = {
 172         {
 173                 .type   = SERIO_RS232,
 174                 .proto  = SERIO_STINGER,
 175                 .id     = SERIO_ANY,
 176                 .extra  = SERIO_ANY,
 177         },
 178         { 0 }
 179 };
 180 
 181 MODULE_DEVICE_TABLE(serio, stinger_serio_ids);
 182 
 183 static struct serio_driver stinger_drv = {
 184         .driver         = {
 185                 .name   = "stinger",
 186         },
 187         .description    = DRIVER_DESC,
 188         .id_table       = stinger_serio_ids,
 189         .interrupt      = stinger_interrupt,
 190         .connect        = stinger_connect,
 191         .disconnect     = stinger_disconnect,
 192 };
 193 
 194 module_serio_driver(stinger_drv);