1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ICS MK712 touchscreen controller driver
4 *
5 * Copyright (c) 1999-2002 Transmeta Corporation
6 * Copyright (c) 2005 Rick Koch <n1gp@hotmail.com>
7 * Copyright (c) 2005 Vojtech Pavlik <vojtech@suse.cz>
8 */
9
10
11/*
12 * This driver supports the ICS MicroClock MK712 TouchScreen controller,
13 * found in Gateway AOL Connected Touchpad computers.
14 *
15 * Documentation for ICS MK712 can be found at:
16 *	https://www.idt.com/general-parts/mk712-touch-screen-controller
17 */
18
19/*
20 * 1999-12-18: original version, Daniel Quinlan
21 * 1999-12-19: added anti-jitter code, report pen-up events, fixed mk712_poll
22 *             to use queue_empty, Nathan Laredo
23 * 1999-12-20: improved random point rejection, Nathan Laredo
24 * 2000-01-05: checked in new anti-jitter code, changed mouse protocol, fixed
25 *             queue code, added module options, other fixes, Daniel Quinlan
26 * 2002-03-15: Clean up for kernel merge <alan@redhat.com>
27 *             Fixed multi open race, fixed memory checks, fixed resource
28 *             allocation, fixed close/powerdown bug, switched to new init
29 * 2005-01-18: Ported to 2.6 from 2.4.28, Rick Koch
30 * 2005-02-05: Rewritten for the input layer, Vojtech Pavlik
31 *
32 */
33
34#include <linux/module.h>
35#include <linux/kernel.h>
36#include <linux/init.h>
37#include <linux/errno.h>
38#include <linux/delay.h>
39#include <linux/ioport.h>
40#include <linux/interrupt.h>
41#include <linux/input.h>
42#include <asm/io.h>
43
44MODULE_AUTHOR("Daniel Quinlan <quinlan@pathname.com>, Vojtech Pavlik <vojtech@suse.cz>");
45MODULE_DESCRIPTION("ICS MicroClock MK712 TouchScreen driver");
46MODULE_LICENSE("GPL");
47
48static unsigned int mk712_io = 0x260;	/* Also 0x200, 0x208, 0x300 */
49module_param_hw_named(io, mk712_io, uint, ioport, 0);
50MODULE_PARM_DESC(io, "I/O base address of MK712 touchscreen controller");
51
52static unsigned int mk712_irq = 10;	/* Also 12, 14, 15 */
53module_param_hw_named(irq, mk712_irq, uint, irq, 0);
54MODULE_PARM_DESC(irq, "IRQ of MK712 touchscreen controller");
55
56/* eight 8-bit registers */
57#define MK712_STATUS		0
58#define MK712_X			2
59#define MK712_Y			4
60#define MK712_CONTROL		6
61#define MK712_RATE		7
62
63/* status */
64#define	MK712_STATUS_TOUCH			0x10
65#define	MK712_CONVERSION_COMPLETE		0x80
66
67/* control */
68#define MK712_ENABLE_INT			0x01
69#define MK712_INT_ON_CONVERSION_COMPLETE	0x02
70#define MK712_INT_ON_CHANGE_IN_TOUCH_STATUS	0x04
71#define MK712_ENABLE_PERIODIC_CONVERSIONS	0x10
72#define MK712_READ_ONE_POINT			0x20
73#define MK712_POWERUP				0x40
74
75static struct input_dev *mk712_dev;
76static DEFINE_SPINLOCK(mk712_lock);
77
78static irqreturn_t mk712_interrupt(int irq, void *dev_id)
79{
80	unsigned char status;
81	static int debounce = 1;
82	static unsigned short last_x;
83	static unsigned short last_y;
84
85	spin_lock(&mk712_lock);
86
87	status = inb(mk712_io + MK712_STATUS);
88
89	if (~status & MK712_CONVERSION_COMPLETE) {
90		debounce = 1;
91		goto end;
92	}
93
94	if (~status & MK712_STATUS_TOUCH) {
95		debounce = 1;
96		input_report_key(mk712_dev, BTN_TOUCH, 0);
97		goto end;
98	}
99
100	if (debounce) {
101		debounce = 0;
102		goto end;
103	}
104
105	input_report_key(mk712_dev, BTN_TOUCH, 1);
106	input_report_abs(mk712_dev, ABS_X, last_x);
107	input_report_abs(mk712_dev, ABS_Y, last_y);
108
109 end:
110	last_x = inw(mk712_io + MK712_X) & 0x0fff;
111	last_y = inw(mk712_io + MK712_Y) & 0x0fff;
112	input_sync(mk712_dev);
113	spin_unlock(&mk712_lock);
114	return IRQ_HANDLED;
115}
116
117static int mk712_open(struct input_dev *dev)
118{
119	unsigned long flags;
120
121	spin_lock_irqsave(&mk712_lock, flags);
122
123	outb(0, mk712_io + MK712_CONTROL); /* Reset */
124
125	outb(MK712_ENABLE_INT | MK712_INT_ON_CONVERSION_COMPLETE |
126		MK712_INT_ON_CHANGE_IN_TOUCH_STATUS |
127		MK712_ENABLE_PERIODIC_CONVERSIONS |
128		MK712_POWERUP, mk712_io + MK712_CONTROL);
129
130	outb(10, mk712_io + MK712_RATE); /* 187 points per second */
131
132	spin_unlock_irqrestore(&mk712_lock, flags);
133
134	return 0;
135}
136
137static void mk712_close(struct input_dev *dev)
138{
139	unsigned long flags;
140
141	spin_lock_irqsave(&mk712_lock, flags);
142
143	outb(0, mk712_io + MK712_CONTROL);
144
145	spin_unlock_irqrestore(&mk712_lock, flags);
146}
147
148static int __init mk712_init(void)
149{
150	int err;
151
152	if (!request_region(mk712_io, 8, "mk712")) {
153		printk(KERN_WARNING "mk712: unable to get IO region\n");
154		return -ENODEV;
155	}
156
157	outb(0, mk712_io + MK712_CONTROL);
158
159	if ((inw(mk712_io + MK712_X) & 0xf000) ||	/* Sanity check */
160	    (inw(mk712_io + MK712_Y) & 0xf000) ||
161	    (inw(mk712_io + MK712_STATUS) & 0xf333)) {
162		printk(KERN_WARNING "mk712: device not present\n");
163		err = -ENODEV;
164		goto fail1;
165	}
166
167	mk712_dev = input_allocate_device();
168	if (!mk712_dev) {
169		printk(KERN_ERR "mk712: not enough memory\n");
170		err = -ENOMEM;
171		goto fail1;
172	}
173
174	mk712_dev->name = "ICS MicroClock MK712 TouchScreen";
175	mk712_dev->phys = "isa0260/input0";
176	mk712_dev->id.bustype = BUS_ISA;
177	mk712_dev->id.vendor  = 0x0005;
178	mk712_dev->id.product = 0x0001;
179	mk712_dev->id.version = 0x0100;
180
181	mk712_dev->open    = mk712_open;
182	mk712_dev->close   = mk712_close;
183
184	mk712_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
185	mk712_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
186	input_set_abs_params(mk712_dev, ABS_X, 0, 0xfff, 88, 0);
187	input_set_abs_params(mk712_dev, ABS_Y, 0, 0xfff, 88, 0);
188
189	if (request_irq(mk712_irq, mk712_interrupt, 0, "mk712", mk712_dev)) {
190		printk(KERN_WARNING "mk712: unable to get IRQ\n");
191		err = -EBUSY;
192		goto fail1;
193	}
194
195	err = input_register_device(mk712_dev);
196	if (err)
197		goto fail2;
198
199	return 0;
200
201 fail2:	free_irq(mk712_irq, mk712_dev);
202 fail1:	input_free_device(mk712_dev);
203	release_region(mk712_io, 8);
204	return err;
205}
206
207static void __exit mk712_exit(void)
208{
209	input_unregister_device(mk712_dev);
210	free_irq(mk712_irq, mk712_dev);
211	release_region(mk712_io, 8);
212}
213
214module_init(mk712_init);
215module_exit(mk712_exit);
216