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 
29 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
30 MODULE_DESCRIPTION("IBM PC110 touchpad driver");
31 MODULE_LICENSE("GPL");
32 
33 #define PC110PAD_OFF	0x30
34 #define PC110PAD_ON	0x38
35 
36 static int pc110pad_irq = 10;
37 static int pc110pad_io = 0x15e0;
38 
39 static struct input_dev *pc110pad_dev;
40 static int pc110pad_data[3];
41 static int pc110pad_count;
42 
pc110pad_interrupt(int irq,void * ptr)43 static 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 
pc110pad_close(struct input_dev * dev)71 static void pc110pad_close(struct input_dev *dev)
72 {
73 	outb(PC110PAD_OFF, pc110pad_io + 2);
74 }
75 
pc110pad_open(struct input_dev * dev)76 static 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  */
pc110pad_init(void)93 static 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 
pc110pad_exit(void)154 static 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 
162 module_init(pc110pad_init);
163 module_exit(pc110pad_exit);
164