input/keyboard/opencores-kbd.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * OpenCores Keyboard Controller Driver
0004  * http://www.opencores.org/project,keyboardcontroller
0005  *
0006  * Copyright 2007-2009 HV Sistemas S.L.
0007  */
0008
0009 #include <linux/input.h>
0010 #include <linux/interrupt.h>
0011 #include <linux/io.h>
0012 #include <linux/ioport.h>
0013 #include <linux/kernel.h>
0014 #include <linux/module.h>
0015 #include <linux/platform_device.h>
0016 #include <linux/slab.h>
0017
0018 struct opencores_kbd {
0019     struct input_dev *input;
0020     void __iomem *addr;
0021     int irq;
0022     unsigned short keycodes[128];
0023 };
0024
0025 static irqreturn_t opencores_kbd_isr(int irq, void *dev_id)
0026 {
0027     struct opencores_kbd *opencores_kbd = dev_id;
0028     struct input_dev *input = opencores_kbd->input;
0029     unsigned char c;
0030
0031     c = readb(opencores_kbd->addr);
0032     input_report_key(input, c & 0x7f, c & 0x80 ? 0 : 1);
0033     input_sync(input);
0034
0035     return IRQ_HANDLED;
0036 }
0037
0038 static int opencores_kbd_probe(struct platform_device *pdev)
0039 {
0040     struct input_dev *input;
0041     struct opencores_kbd *opencores_kbd;
0042     struct resource *res;
0043     int irq, i, error;
0044
0045     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
0046     if (!res) {
0047         dev_err(&pdev->dev, "missing board memory resource\n");
0048         return -EINVAL;
0049     }
0050
0051     irq = platform_get_irq(pdev, 0);
0052     if (irq < 0)
0053         return -EINVAL;
0054
0055     opencores_kbd = devm_kzalloc(&pdev->dev, sizeof(*opencores_kbd),
0056                      GFP_KERNEL);
0057     if (!opencores_kbd)
0058         return -ENOMEM;
0059
0060     input = devm_input_allocate_device(&pdev->dev);
0061     if (!input) {
0062         dev_err(&pdev->dev, "failed to allocate input device\n");
0063         return -ENOMEM;
0064     }
0065
0066     opencores_kbd->input = input;
0067
0068     opencores_kbd->addr = devm_ioremap_resource(&pdev->dev, res);
0069     if (IS_ERR(opencores_kbd->addr))
0070         return PTR_ERR(opencores_kbd->addr);
0071
0072     input->name = pdev->name;
0073     input->phys = "opencores-kbd/input0";
0074
0075     input->id.bustype = BUS_HOST;
0076     input->id.vendor = 0x0001;
0077     input->id.product = 0x0001;
0078     input->id.version = 0x0100;
0079
0080     input->keycode = opencores_kbd->keycodes;
0081     input->keycodesize = sizeof(opencores_kbd->keycodes[0]);
0082     input->keycodemax = ARRAY_SIZE(opencores_kbd->keycodes);
0083
0084     __set_bit(EV_KEY, input->evbit);
0085
0086     for (i = 0; i < ARRAY_SIZE(opencores_kbd->keycodes); i++) {
0087         /*
0088          * OpenCores controller happens to have scancodes match
0089          * our KEY_* definitions.
0090          */
0091         opencores_kbd->keycodes[i] = i;
0092         __set_bit(opencores_kbd->keycodes[i], input->keybit);
0093     }
0094     __clear_bit(KEY_RESERVED, input->keybit);
0095
0096     error = devm_request_irq(&pdev->dev, irq, &opencores_kbd_isr,
0097                  IRQF_TRIGGER_RISING,
0098                  pdev->name, opencores_kbd);
0099     if (error) {
0100         dev_err(&pdev->dev, "unable to claim irq %d\n", irq);
0101         return error;
0102     }
0103
0104     error = input_register_device(input);
0105     if (error) {
0106         dev_err(&pdev->dev, "unable to register input device\n");
0107         return error;
0108     }
0109
0110     return 0;
0111 }
0112
0113 static struct platform_driver opencores_kbd_device_driver = {
0114     .probe    = opencores_kbd_probe,
0115     .driver   = {
0116         .name = "opencores-kbd",
0117     },
0118 };
0119 module_platform_driver(opencores_kbd_device_driver);
0120
0121 MODULE_LICENSE("GPL");
0122 MODULE_AUTHOR("Javier Herrero <jherrero@hvsistemas.es>");
0123 MODULE_DESCRIPTION("Keyboard driver for OpenCores Keyboard Controller");