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 
26 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
27 MODULE_DESCRIPTION("IBM PC110 touchpad driver");
28 MODULE_LICENSE("GPL");
29 
30 #define PC110PAD_OFF	0x30
31 #define PC110PAD_ON	0x38
32 
33 static int pc110pad_irq = 10;
34 static int pc110pad_io = 0x15e0;
35 
36 static struct input_dev *pc110pad_dev;
37 static int pc110pad_data[3];
38 static int pc110pad_count;
39 
pc110pad_interrupt(int irq,void * ptr)40 static 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 
pc110pad_close(struct input_dev * dev)68 static void pc110pad_close(struct input_dev *dev)
69 {
70 	outb(PC110PAD_OFF, pc110pad_io + 2);
71 }
72 
pc110pad_open(struct input_dev * dev)73 static 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  */
pc110pad_init(void)90 static 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 
pc110pad_exit(void)151 static 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 
159 module_init(pc110pad_init);
160 module_exit(pc110pad_exit);
161