1 /*
2  * ICS MK712 touchscreen controller driver
3  *
4  * Copyright (c) 1999-2002 Transmeta Corporation
5  * Copyright (c) 2005 Rick Koch <n1gp@hotmail.com>
6  * Copyright (c) 2005 Vojtech Pavlik <vojtech@suse.cz>
7  */
8 
9 /*
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License version 2 as published by
12  * the Free Software Foundation.
13  */
14 
15 /*
16  * This driver supports the ICS MicroClock MK712 TouchScreen controller,
17  * found in Gateway AOL Connected Touchpad computers.
18  *
19  * Documentation for ICS MK712 can be found at:
20  *	https://www.idt.com/general-parts/mk712-touch-screen-controller
21  */
22 
23 /*
24  * 1999-12-18: original version, Daniel Quinlan
25  * 1999-12-19: added anti-jitter code, report pen-up events, fixed mk712_poll
26  *             to use queue_empty, Nathan Laredo
27  * 1999-12-20: improved random point rejection, Nathan Laredo
28  * 2000-01-05: checked in new anti-jitter code, changed mouse protocol, fixed
29  *             queue code, added module options, other fixes, Daniel Quinlan
30  * 2002-03-15: Clean up for kernel merge <alan@redhat.com>
31  *             Fixed multi open race, fixed memory checks, fixed resource
32  *             allocation, fixed close/powerdown bug, switched to new init
33  * 2005-01-18: Ported to 2.6 from 2.4.28, Rick Koch
34  * 2005-02-05: Rewritten for the input layer, Vojtech Pavlik
35  *
36  */
37 
38 #include <linux/module.h>
39 #include <linux/kernel.h>
40 #include <linux/init.h>
41 #include <linux/errno.h>
42 #include <linux/delay.h>
43 #include <linux/ioport.h>
44 #include <linux/interrupt.h>
45 #include <linux/input.h>
46 #include <asm/io.h>
47 
48 MODULE_AUTHOR("Daniel Quinlan <quinlan@pathname.com>, Vojtech Pavlik <vojtech@suse.cz>");
49 MODULE_DESCRIPTION("ICS MicroClock MK712 TouchScreen driver");
50 MODULE_LICENSE("GPL");
51 
52 static unsigned int mk712_io = 0x260;	/* Also 0x200, 0x208, 0x300 */
53 module_param_hw_named(io, mk712_io, uint, ioport, 0);
54 MODULE_PARM_DESC(io, "I/O base address of MK712 touchscreen controller");
55 
56 static unsigned int mk712_irq = 10;	/* Also 12, 14, 15 */
57 module_param_hw_named(irq, mk712_irq, uint, irq, 0);
58 MODULE_PARM_DESC(irq, "IRQ of MK712 touchscreen controller");
59 
60 /* eight 8-bit registers */
61 #define MK712_STATUS		0
62 #define MK712_X			2
63 #define MK712_Y			4
64 #define MK712_CONTROL		6
65 #define MK712_RATE		7
66 
67 /* status */
68 #define	MK712_STATUS_TOUCH			0x10
69 #define	MK712_CONVERSION_COMPLETE		0x80
70 
71 /* control */
72 #define MK712_ENABLE_INT			0x01
73 #define MK712_INT_ON_CONVERSION_COMPLETE	0x02
74 #define MK712_INT_ON_CHANGE_IN_TOUCH_STATUS	0x04
75 #define MK712_ENABLE_PERIODIC_CONVERSIONS	0x10
76 #define MK712_READ_ONE_POINT			0x20
77 #define MK712_POWERUP				0x40
78 
79 static struct input_dev *mk712_dev;
80 static DEFINE_SPINLOCK(mk712_lock);
81 
82 static irqreturn_t mk712_interrupt(int irq, void *dev_id)
83 {
84 	unsigned char status;
85 	static int debounce = 1;
86 	static unsigned short last_x;
87 	static unsigned short last_y;
88 
89 	spin_lock(&mk712_lock);
90 
91 	status = inb(mk712_io + MK712_STATUS);
92 
93 	if (~status & MK712_CONVERSION_COMPLETE) {
94 		debounce = 1;
95 		goto end;
96 	}
97 
98 	if (~status & MK712_STATUS_TOUCH) {
99 		debounce = 1;
100 		input_report_key(mk712_dev, BTN_TOUCH, 0);
101 		goto end;
102 	}
103 
104 	if (debounce) {
105 		debounce = 0;
106 		goto end;
107 	}
108 
109 	input_report_key(mk712_dev, BTN_TOUCH, 1);
110 	input_report_abs(mk712_dev, ABS_X, last_x);
111 	input_report_abs(mk712_dev, ABS_Y, last_y);
112 
113  end:
114 	last_x = inw(mk712_io + MK712_X) & 0x0fff;
115 	last_y = inw(mk712_io + MK712_Y) & 0x0fff;
116 	input_sync(mk712_dev);
117 	spin_unlock(&mk712_lock);
118 	return IRQ_HANDLED;
119 }
120 
121 static int mk712_open(struct input_dev *dev)
122 {
123 	unsigned long flags;
124 
125 	spin_lock_irqsave(&mk712_lock, flags);
126 
127 	outb(0, mk712_io + MK712_CONTROL); /* Reset */
128 
129 	outb(MK712_ENABLE_INT | MK712_INT_ON_CONVERSION_COMPLETE |
130 		MK712_INT_ON_CHANGE_IN_TOUCH_STATUS |
131 		MK712_ENABLE_PERIODIC_CONVERSIONS |
132 		MK712_POWERUP, mk712_io + MK712_CONTROL);
133 
134 	outb(10, mk712_io + MK712_RATE); /* 187 points per second */
135 
136 	spin_unlock_irqrestore(&mk712_lock, flags);
137 
138 	return 0;
139 }
140 
141 static void mk712_close(struct input_dev *dev)
142 {
143 	unsigned long flags;
144 
145 	spin_lock_irqsave(&mk712_lock, flags);
146 
147 	outb(0, mk712_io + MK712_CONTROL);
148 
149 	spin_unlock_irqrestore(&mk712_lock, flags);
150 }
151 
152 static int __init mk712_init(void)
153 {
154 	int err;
155 
156 	if (!request_region(mk712_io, 8, "mk712")) {
157 		printk(KERN_WARNING "mk712: unable to get IO region\n");
158 		return -ENODEV;
159 	}
160 
161 	outb(0, mk712_io + MK712_CONTROL);
162 
163 	if ((inw(mk712_io + MK712_X) & 0xf000) ||	/* Sanity check */
164 	    (inw(mk712_io + MK712_Y) & 0xf000) ||
165 	    (inw(mk712_io + MK712_STATUS) & 0xf333)) {
166 		printk(KERN_WARNING "mk712: device not present\n");
167 		err = -ENODEV;
168 		goto fail1;
169 	}
170 
171 	mk712_dev = input_allocate_device();
172 	if (!mk712_dev) {
173 		printk(KERN_ERR "mk712: not enough memory\n");
174 		err = -ENOMEM;
175 		goto fail1;
176 	}
177 
178 	mk712_dev->name = "ICS MicroClock MK712 TouchScreen";
179 	mk712_dev->phys = "isa0260/input0";
180 	mk712_dev->id.bustype = BUS_ISA;
181 	mk712_dev->id.vendor  = 0x0005;
182 	mk712_dev->id.product = 0x0001;
183 	mk712_dev->id.version = 0x0100;
184 
185 	mk712_dev->open    = mk712_open;
186 	mk712_dev->close   = mk712_close;
187 
188 	mk712_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
189 	mk712_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
190 	input_set_abs_params(mk712_dev, ABS_X, 0, 0xfff, 88, 0);
191 	input_set_abs_params(mk712_dev, ABS_Y, 0, 0xfff, 88, 0);
192 
193 	if (request_irq(mk712_irq, mk712_interrupt, 0, "mk712", mk712_dev)) {
194 		printk(KERN_WARNING "mk712: unable to get IRQ\n");
195 		err = -EBUSY;
196 		goto fail1;
197 	}
198 
199 	err = input_register_device(mk712_dev);
200 	if (err)
201 		goto fail2;
202 
203 	return 0;
204 
205  fail2:	free_irq(mk712_irq, mk712_dev);
206  fail1:	input_free_device(mk712_dev);
207 	release_region(mk712_io, 8);
208 	return err;
209 }
210 
211 static void __exit mk712_exit(void)
212 {
213 	input_unregister_device(mk712_dev);
214 	free_irq(mk712_irq, mk712_dev);
215 	release_region(mk712_io, 8);
216 }
217 
218 module_init(mk712_init);
219 module_exit(mk712_exit);
220