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/*
14 */
15
16#include <linux/module.h>
17#include <linux/kernel.h>
18#include <linux/errno.h>
19#include <linux/ioport.h>
20#include <linux/input.h>
21#include <linux/init.h>
22#include <linux/interrupt.h>
23#include <linux/pci.h>
24#include <linux/delay.h>
25
26#include <asm/io.h>
27#include <asm/irq.h>
28
29MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
30MODULE_DESCRIPTION("IBM PC110 touchpad driver");
31MODULE_LICENSE("GPL");
32
33#define PC110PAD_OFF	0x30
34#define PC110PAD_ON	0x38
35
36static int pc110pad_irq = 10;
37static int pc110pad_io = 0x15e0;
38
39static struct input_dev *pc110pad_dev;
40static int pc110pad_data[3];
41static int pc110pad_count;
42
43static irqreturn_t pc110pad_interrupt(int irq, void *ptr)
44{
45	int value     = inb_p(pc110pad_io);
46	int handshake = inb_p(pc110pad_io + 2);
47
48	outb(handshake |  1, pc110pad_io + 2);
49	udelay(2);
50	outb(handshake & ~1, pc110pad_io + 2);
51	udelay(2);
52	inb_p(0x64);
53
54	pc110pad_data[pc110pad_count++] = value;
55
56	if (pc110pad_count < 3)
57		return IRQ_HANDLED;
58
59	input_report_key(pc110pad_dev, BTN_TOUCH,
60		pc110pad_data[0] & 0x01);
61	input_report_abs(pc110pad_dev, ABS_X,
62		pc110pad_data[1] | ((pc110pad_data[0] << 3) & 0x80) | ((pc110pad_data[0] << 1) & 0x100));
63	input_report_abs(pc110pad_dev, ABS_Y,
64		pc110pad_data[2] | ((pc110pad_data[0] << 4) & 0x80));
65	input_sync(pc110pad_dev);
66
67	pc110pad_count = 0;
68	return IRQ_HANDLED;
69}
70
71static void pc110pad_close(struct input_dev *dev)
72{
73	outb(PC110PAD_OFF, pc110pad_io + 2);
74}
75
76static int pc110pad_open(struct input_dev *dev)
77{
78	pc110pad_interrupt(0, NULL);
79	pc110pad_interrupt(0, NULL);
80	pc110pad_interrupt(0, NULL);
81	outb(PC110PAD_ON, pc110pad_io + 2);
82	pc110pad_count = 0;
83
84	return 0;
85}
86
87/*
88 * We try to avoid enabling the hardware if it's not
89 * there, but we don't know how to test. But we do know
90 * that the PC110 is not a PCI system. So if we find any
91 * PCI devices in the machine, we don't have a PC110.
92 */
93static int __init pc110pad_init(void)
94{
95	int err;
96
97	if (!no_pci_devices())
98		return -ENODEV;
99
100	if (!request_region(pc110pad_io, 4, "pc110pad")) {
101		printk(KERN_ERR "pc110pad: I/O area %#x-%#x in use.\n",
102				pc110pad_io, pc110pad_io + 4);
103		return -EBUSY;
104	}
105
106	outb(PC110PAD_OFF, pc110pad_io + 2);
107
108	if (request_irq(pc110pad_irq, pc110pad_interrupt, 0, "pc110pad", NULL)) {
109		printk(KERN_ERR "pc110pad: Unable to get irq %d.\n", pc110pad_irq);
110		err = -EBUSY;
111		goto err_release_region;
112	}
113
114	pc110pad_dev = input_allocate_device();
115	if (!pc110pad_dev) {
116		printk(KERN_ERR "pc110pad: Not enough memory.\n");
117		err = -ENOMEM;
118		goto err_free_irq;
119	}
120
121	pc110pad_dev->name = "IBM PC110 TouchPad";
122	pc110pad_dev->phys = "isa15e0/input0";
123	pc110pad_dev->id.bustype = BUS_ISA;
124	pc110pad_dev->id.vendor = 0x0003;
125	pc110pad_dev->id.product = 0x0001;
126	pc110pad_dev->id.version = 0x0100;
127
128	pc110pad_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
129	pc110pad_dev->absbit[0] = BIT_MASK(ABS_X) | BIT_MASK(ABS_Y);
130	pc110pad_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
131
132	input_abs_set_max(pc110pad_dev, ABS_X, 0x1ff);
133	input_abs_set_max(pc110pad_dev, ABS_Y, 0x0ff);
134
135	pc110pad_dev->open = pc110pad_open;
136	pc110pad_dev->close = pc110pad_close;
137
138	err = input_register_device(pc110pad_dev);
139	if (err)
140		goto err_free_dev;
141
142	return 0;
143
144 err_free_dev:
145	input_free_device(pc110pad_dev);
146 err_free_irq:
147	free_irq(pc110pad_irq, NULL);
148 err_release_region:
149	release_region(pc110pad_io, 4);
150
151	return err;
152}
153
154static void __exit pc110pad_exit(void)
155{
156	outb(PC110PAD_OFF, pc110pad_io + 2);
157	free_irq(pc110pad_irq, NULL);
158	input_unregister_device(pc110pad_dev);
159	release_region(pc110pad_io, 4);
160}
161
162module_init(pc110pad_init);
163module_exit(pc110pad_exit);
164