drivers/input/keyboard/opencores-kbd.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * OpenCores Keyboard Controller Driver
   4  * http://www.opencores.org/project,keyboardcontroller
   5  *
   6  * Copyright 2007-2009 HV Sistemas S.L.
   7  */
   8
   9 #include <linux/input.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/io.h>
  12 #include <linux/ioport.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/slab.h>
  17
  18 struct opencores_kbd {
  19         struct input_dev *input;
  20         void __iomem *addr;
  21         int irq;
  22         unsigned short keycodes[128];
  23 };
  24
  25 static irqreturn_t opencores_kbd_isr(int irq, void *dev_id)
  26 {
  27         struct opencores_kbd *opencores_kbd = dev_id;
  28         struct input_dev *input = opencores_kbd->input;
  29         unsigned char c;
  30
  31         c = readb(opencores_kbd->addr);
  32         input_report_key(input, c & 0x7f, c & 0x80 ? 0 : 1);
  33         input_sync(input);
  34
  35         return IRQ_HANDLED;
  36 }
  37
  38 static int opencores_kbd_probe(struct platform_device *pdev)
  39 {
  40         struct input_dev *input;
  41         struct opencores_kbd *opencores_kbd;
  42         int irq, i, error;
  43
  44         irq = platform_get_irq(pdev, 0);
  45         if (irq < 0)
  46                 return -EINVAL;
  47
  48         opencores_kbd = devm_kzalloc(&pdev->dev, sizeof(*opencores_kbd),
  49                                      GFP_KERNEL);
  50         if (!opencores_kbd)
  51                 return -ENOMEM;
  52
  53         input = devm_input_allocate_device(&pdev->dev);
  54         if (!input) {
  55                 dev_err(&pdev->dev, "failed to allocate input device\n");
  56                 return -ENOMEM;
  57         }
  58
  59         opencores_kbd->input = input;
  60
  61         opencores_kbd->addr = devm_platform_ioremap_resource(pdev, 0);
  62         if (IS_ERR(opencores_kbd->addr))
  63                 return PTR_ERR(opencores_kbd->addr);
  64
  65         input->name = pdev->name;
  66         input->phys = "opencores-kbd/input0";
  67
  68         input->id.bustype = BUS_HOST;
  69         input->id.vendor = 0x0001;
  70         input->id.product = 0x0001;
  71         input->id.version = 0x0100;
  72
  73         input->keycode = opencores_kbd->keycodes;
  74         input->keycodesize = sizeof(opencores_kbd->keycodes[0]);
  75         input->keycodemax = ARRAY_SIZE(opencores_kbd->keycodes);
  76
  77         __set_bit(EV_KEY, input->evbit);
  78
  79         for (i = 0; i < ARRAY_SIZE(opencores_kbd->keycodes); i++) {
  80                 /*
  81                  * OpenCores controller happens to have scancodes match
  82                  * our KEY_* definitions.
  83                  */
  84                 opencores_kbd->keycodes[i] = i;
  85                 __set_bit(opencores_kbd->keycodes[i], input->keybit);
  86         }
  87         __clear_bit(KEY_RESERVED, input->keybit);
  88
  89         error = devm_request_irq(&pdev->dev, irq, &opencores_kbd_isr,
  90                                  IRQF_TRIGGER_RISING,
  91                                  pdev->name, opencores_kbd);
  92         if (error) {
  93                 dev_err(&pdev->dev, "unable to claim irq %d\n", irq);
  94                 return error;
  95         }
  96
  97         error = input_register_device(input);
  98         if (error) {
  99                 dev_err(&pdev->dev, "unable to register input device\n");
 100                 return error;
 101         }
 102
 103         return 0;
 104 }
 105
 106 static struct platform_driver opencores_kbd_device_driver = {
 107         .probe    = opencores_kbd_probe,
 108         .driver   = {
 109                 .name = "opencores-kbd",
 110         },
 111 };
 112 module_platform_driver(opencores_kbd_device_driver);
 113
 114 MODULE_LICENSE("GPL");
 115 MODULE_AUTHOR("Javier Herrero <jherrero@hvsistemas.es>");
 116 MODULE_DESCRIPTION("Keyboard driver for OpenCores Keyboard Controller");