pc110pad.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Copyright (c) 2000-2001 Vojtech Pavlik
  4 *
  5 *  Based on the work of:
  6 *	Alan Cox	Robin O'Leary
  7 */
  8
  9/*
 10 * IBM PC110 touchpad driver for Linux
 11 */
 12
 13#include <linux/module.h>
 14#include <linux/kernel.h>
 15#include <linux/errno.h>
 16#include <linux/ioport.h>
 17#include <linux/input.h>
 18#include <linux/init.h>
 19#include <linux/interrupt.h>
 20#include <linux/pci.h>
 21#include <linux/delay.h>
 22
 23#include <asm/io.h>
 24#include <asm/irq.h>
 25
 26MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
 27MODULE_DESCRIPTION("IBM PC110 touchpad driver");
 28MODULE_LICENSE("GPL");
 29
 30#define PC110PAD_OFF	0x30
 31#define PC110PAD_ON	0x38
 32
 33static int pc110pad_irq = 10;
 34static int pc110pad_io = 0x15e0;
 35
 36static struct input_dev *pc110pad_dev;
 37static int pc110pad_data[3];
 38static int pc110pad_count;
 39
 40static irqreturn_t pc110pad_interrupt(int irq, void *ptr)
 41{
 42	int value     = inb_p(pc110pad_io);
 43	int handshake = inb_p(pc110pad_io + 2);
 44
 45	outb(handshake |  1, pc110pad_io + 2);
 46	udelay(2);
 47	outb(handshake & ~1, pc110pad_io + 2);
 48	udelay(2);
 49	inb_p(0x64);
 50
 51	pc110pad_data[pc110pad_count++] = value;
 52
 53	if (pc110pad_count < 3)
 54		return IRQ_HANDLED;
 55
 56	input_report_key(pc110pad_dev, BTN_TOUCH,
 57		pc110pad_data[0] & 0x01);
 58	input_report_abs(pc110pad_dev, ABS_X,
 59		pc110pad_data[1] | ((pc110pad_data[0] << 3) & 0x80) | ((pc110pad_data[0] << 1) & 0x100));
 60	input_report_abs(pc110pad_dev, ABS_Y,
 61		pc110pad_data[2] | ((pc110pad_data[0] << 4) & 0x80));
 62	input_sync(pc110pad_dev);
 63
 64	pc110pad_count = 0;
 65	return IRQ_HANDLED;
 66}
 67
 68static void pc110pad_close(struct input_dev *dev)
 69{
 70	outb(PC110PAD_OFF, pc110pad_io + 2);
 71}
 72
 73static int pc110pad_open(struct input_dev *dev)
 74{
 75	pc110pad_interrupt(0, NULL);
 76	pc110pad_interrupt(0, NULL);
 77	pc110pad_interrupt(0, NULL);
 78	outb(PC110PAD_ON, pc110pad_io + 2);
 79	pc110pad_count = 0;
 80
 81	return 0;
 82}
 83
 84/*
 85 * We try to avoid enabling the hardware if it's not
 86 * there, but we don't know how to test. But we do know
 87 * that the PC110 is not a PCI system. So if we find any
 88 * PCI devices in the machine, we don't have a PC110.
 89 */
 90static int __init pc110pad_init(void)
 91{
 92	int err;
 93
 94	if (!no_pci_devices())
 95		return -ENODEV;
 96
 97	if (!request_region(pc110pad_io, 4, "pc110pad")) {
 98		printk(KERN_ERR "pc110pad: I/O area %#x-%#x in use.\n",
 99				pc110pad_io, pc110pad_io + 4);
100		return -EBUSY;
101	}
102
103	outb(PC110PAD_OFF, pc110pad_io + 2);
104
105	if (request_irq(pc110pad_irq, pc110pad_interrupt, 0, "pc110pad", NULL)) {
106		printk(KERN_ERR "pc110pad: Unable to get irq %d.\n", pc110pad_irq);
107		err = -EBUSY;
108		goto err_release_region;
109	}
110
111	pc110pad_dev = input_allocate_device();
112	if (!pc110pad_dev) {
113		printk(KERN_ERR "pc110pad: Not enough memory.\n");
114		err = -ENOMEM;
115		goto err_free_irq;
116	}
117
118	pc110pad_dev->name = "IBM PC110 TouchPad";
119	pc110pad_dev->phys = "isa15e0/input0";
120	pc110pad_dev->id.bustype = BUS_ISA;
121	pc110pad_dev->id.vendor = 0x0003;
122	pc110pad_dev->id.product = 0x0001;
123	pc110pad_dev->id.version = 0x0100;
124
125	pc110pad_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
126	pc110pad_dev->absbit[0] = BIT_MASK(ABS_X) | BIT_MASK(ABS_Y);
127	pc110pad_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
128
129	input_abs_set_max(pc110pad_dev, ABS_X, 0x1ff);
130	input_abs_set_max(pc110pad_dev, ABS_Y, 0x0ff);
131
132	pc110pad_dev->open = pc110pad_open;
133	pc110pad_dev->close = pc110pad_close;
134
135	err = input_register_device(pc110pad_dev);
136	if (err)
137		goto err_free_dev;
138
139	return 0;
140
141 err_free_dev:
142	input_free_device(pc110pad_dev);
143 err_free_irq:
144	free_irq(pc110pad_irq, NULL);
145 err_release_region:
146	release_region(pc110pad_io, 4);
147
148	return err;
149}
150
151static void __exit pc110pad_exit(void)
152{
153	outb(PC110PAD_OFF, pc110pad_io + 2);
154	free_irq(pc110pad_irq, NULL);
155	input_unregister_device(pc110pad_dev);
156	release_region(pc110pad_io, 4);
157}
158
159module_init(pc110pad_init);
160module_exit(pc110pad_exit);