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  *	http://www.icst.com/pdf/mk712.pdf
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/moduleparam.h>
40 #include <linux/kernel.h>
41 #include <linux/init.h>
42 #include <linux/errno.h>
43 #include <linux/delay.h>
44 #include <linux/ioport.h>
45 #include <linux/interrupt.h>
46 #include <linux/input.h>
47 #include <asm/io.h>
48 
49 MODULE_AUTHOR("Daniel Quinlan <quinlan@pathname.com>, Vojtech Pavlik <vojtech@suse.cz>");
50 MODULE_DESCRIPTION("ICS MicroClock MK712 TouchScreen driver");
51 MODULE_LICENSE("GPL");
52 
53 static unsigned int mk712_io = 0x260;	/* Also 0x200, 0x208, 0x300 */
54 module_param_named(io, mk712_io, uint, 0);
55 MODULE_PARM_DESC(io, "I/O base address of MK712 touchscreen controller");
56 
57 static unsigned int mk712_irq = 10;	/* Also 12, 14, 15 */
58 module_param_named(irq, mk712_irq, uint, 0);
59 MODULE_PARM_DESC(irq, "IRQ of MK712 touchscreen controller");
60 
61 /* eight 8-bit registers */
62 #define MK712_STATUS		0
63 #define MK712_X			2
64 #define MK712_Y			4
65 #define MK712_CONTROL		6
66 #define MK712_RATE		7
67 
68 /* status */
69 #define	MK712_STATUS_TOUCH			0x10
70 #define	MK712_CONVERSION_COMPLETE		0x80
71 
72 /* control */
73 #define MK712_ENABLE_INT			0x01
74 #define MK712_INT_ON_CONVERSION_COMPLETE	0x02
75 #define MK712_INT_ON_CHANGE_IN_TOUCH_STATUS	0x04
76 #define MK712_ENABLE_PERIODIC_CONVERSIONS	0x10
77 #define MK712_READ_ONE_POINT			0x20
78 #define MK712_POWERUP				0x40
79 
80 static struct input_dev *mk712_dev;
81 static DEFINE_SPINLOCK(mk712_lock);
82 
83 static irqreturn_t mk712_interrupt(int irq, void *dev_id)
84 {
85 	unsigned char status;
86 	static int debounce = 1;
87 	static unsigned short last_x;
88 	static unsigned short last_y;
89 
90 	spin_lock(&mk712_lock);
91 
92 	status = inb(mk712_io + MK712_STATUS);
93 
94 	if (~status & MK712_CONVERSION_COMPLETE) {
95 		debounce = 1;
96 		goto end;
97 	}
98 
99 	if (~status & MK712_STATUS_TOUCH) {
100 		debounce = 1;
101 		input_report_key(mk712_dev, BTN_TOUCH, 0);
102 		goto end;
103 	}
104 
105 	if (debounce) {
106 		debounce = 0;
107 		goto end;
108 	}
109 
110 	input_report_key(mk712_dev, BTN_TOUCH, 1);
111 	input_report_abs(mk712_dev, ABS_X, last_x);
112 	input_report_abs(mk712_dev, ABS_Y, last_y);
113 
114  end:
115 	last_x = inw(mk712_io + MK712_X) & 0x0fff;
116 	last_y = inw(mk712_io + MK712_Y) & 0x0fff;
117 	input_sync(mk712_dev);
118 	spin_unlock(&mk712_lock);
119 	return IRQ_HANDLED;
120 }
121 
122 static int mk712_open(struct input_dev *dev)
123 {
124 	unsigned long flags;
125 
126 	spin_lock_irqsave(&mk712_lock, flags);
127 
128 	outb(0, mk712_io + MK712_CONTROL); /* Reset */
129 
130 	outb(MK712_ENABLE_INT | MK712_INT_ON_CONVERSION_COMPLETE |
131 		MK712_INT_ON_CHANGE_IN_TOUCH_STATUS |
132 		MK712_ENABLE_PERIODIC_CONVERSIONS |
133 		MK712_POWERUP, mk712_io + MK712_CONTROL);
134 
135 	outb(10, mk712_io + MK712_RATE); /* 187 points per second */
136 
137 	spin_unlock_irqrestore(&mk712_lock, flags);
138 
139 	return 0;
140 }
141 
142 static void mk712_close(struct input_dev *dev)
143 {
144 	unsigned long flags;
145 
146 	spin_lock_irqsave(&mk712_lock, flags);
147 
148 	outb(0, mk712_io + MK712_CONTROL);
149 
150 	spin_unlock_irqrestore(&mk712_lock, flags);
151 }
152 
153 static int __init mk712_init(void)
154 {
155 	int err;
156 
157 	if (!request_region(mk712_io, 8, "mk712")) {
158 		printk(KERN_WARNING "mk712: unable to get IO region\n");
159 		return -ENODEV;
160 	}
161 
162 	outb(0, mk712_io + MK712_CONTROL);
163 
164 	if ((inw(mk712_io + MK712_X) & 0xf000) ||	/* Sanity check */
165 	    (inw(mk712_io + MK712_Y) & 0xf000) ||
166 	    (inw(mk712_io + MK712_STATUS) & 0xf333)) {
167 		printk(KERN_WARNING "mk712: device not present\n");
168 		err = -ENODEV;
169 		goto fail1;
170 	}
171 
172 	mk712_dev = input_allocate_device();
173 	if (!mk712_dev) {
174 		printk(KERN_ERR "mk712: not enough memory\n");
175 		err = -ENOMEM;
176 		goto fail1;
177 	}
178 
179 	mk712_dev->name = "ICS MicroClock MK712 TouchScreen";
180 	mk712_dev->phys = "isa0260/input0";
181 	mk712_dev->id.bustype = BUS_ISA;
182 	mk712_dev->id.vendor  = 0x0005;
183 	mk712_dev->id.product = 0x0001;
184 	mk712_dev->id.version = 0x0100;
185 
186 	mk712_dev->open    = mk712_open;
187 	mk712_dev->close   = mk712_close;
188 
189 	mk712_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
190 	mk712_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
191 	input_set_abs_params(mk712_dev, ABS_X, 0, 0xfff, 88, 0);
192 	input_set_abs_params(mk712_dev, ABS_Y, 0, 0xfff, 88, 0);
193 
194 	if (request_irq(mk712_irq, mk712_interrupt, 0, "mk712", mk712_dev)) {
195 		printk(KERN_WARNING "mk712: unable to get IRQ\n");
196 		err = -EBUSY;
197 		goto fail1;
198 	}
199 
200 	err = input_register_device(mk712_dev);
201 	if (err)
202 		goto fail2;
203 
204 	return 0;
205 
206  fail2:	free_irq(mk712_irq, mk712_dev);
207  fail1:	input_free_device(mk712_dev);
208 	release_region(mk712_io, 8);
209 	return err;
210 }
211 
212 static void __exit mk712_exit(void)
213 {
214 	input_unregister_device(mk712_dev);
215 	free_irq(mk712_irq, mk712_dev);
216 	release_region(mk712_io, 8);
217 }
218 
219 module_init(mk712_init);
220 module_exit(mk712_exit);
221