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 int mk712_used = 0;
81 static struct input_dev mk712_dev;
82 static DEFINE_SPINLOCK(mk712_lock);
83 
84 static irqreturn_t mk712_interrupt(int irq, void *dev_id, struct pt_regs *regs)
85 {
86 	unsigned char status;
87 	static int debounce = 1;
88 	static unsigned short last_x;
89 	static unsigned short last_y;
90 
91 	spin_lock(&mk712_lock);
92 	input_regs(&mk712_dev, regs);
93 
94 	status = inb(mk712_io + MK712_STATUS);
95 
96 	if (~status & MK712_CONVERSION_COMPLETE) {
97 		debounce = 1;
98 		goto end;
99 	}
100 
101 	if (~status & MK712_STATUS_TOUCH)
102 	{
103 		debounce = 1;
104 		input_report_key(&mk712_dev, BTN_TOUCH, 0);
105 		goto end;
106 	}
107 
108 	if (debounce)
109 	{
110 		debounce = 0;
111 		goto end;
112 	}
113 
114 	input_report_key(&mk712_dev, BTN_TOUCH, 1);
115 	input_report_abs(&mk712_dev, ABS_X, last_x);
116 	input_report_abs(&mk712_dev, ABS_Y, last_y);
117 
118 end:
119 
120 	last_x = inw(mk712_io + MK712_X) & 0x0fff;
121 	last_y = inw(mk712_io + MK712_Y) & 0x0fff;
122 	input_sync(&mk712_dev);
123 	spin_unlock(&mk712_lock);
124 	return IRQ_HANDLED;
125 }
126 
127 static int mk712_open(struct input_dev *dev)
128 {
129 	unsigned long flags;
130 
131 	spin_lock_irqsave(&mk712_lock, flags);
132 
133 	if (!mk712_used++) {
134 
135 		outb(0, mk712_io + MK712_CONTROL); /* Reset */
136 
137 		outb(MK712_ENABLE_INT | MK712_INT_ON_CONVERSION_COMPLETE |
138 			MK712_INT_ON_CHANGE_IN_TOUCH_STATUS |
139 			MK712_ENABLE_PERIODIC_CONVERSIONS |
140 			MK712_POWERUP, mk712_io + MK712_CONTROL);
141 
142 		outb(10, mk712_io + MK712_RATE); /* 187 points per second */
143 	}
144 
145 	spin_unlock_irqrestore(&mk712_lock, flags);
146 
147 	return 0;
148 }
149 
150 static void mk712_close(struct input_dev *dev)
151 {
152 	unsigned long flags;
153 
154 	spin_lock_irqsave(&mk712_lock, flags);
155 
156 	if (!--mk712_used)
157 		outb(0, mk712_io + MK712_CONTROL);
158 
159 	spin_unlock_irqrestore(&mk712_lock, flags);
160 }
161 
162 static struct input_dev mk712_dev = {
163 	.evbit   = { BIT(EV_KEY) | BIT(EV_ABS) },
164 	.keybit  = { [LONG(BTN_TOUCH)] = BIT(BTN_TOUCH) },
165 	.absbit  = { BIT(ABS_X) | BIT(ABS_Y) },
166 	.open    = mk712_open,
167 	.close   = mk712_close,
168 	.name    = "ICS MicroClock MK712 TouchScreen",
169 	.phys    = "isa0260/input0",
170 	.absmin  = { [ABS_X] = 0, [ABS_Y] = 0 },
171 	.absmax  = { [ABS_X] = 0xfff, [ABS_Y] = 0xfff },
172 	.absfuzz = { [ABS_X] = 88, [ABS_Y] = 88 },
173 	.id      = {
174 		.bustype = BUS_ISA,
175 		.vendor  = 0x0005,
176 		.product = 0x0001,
177 		.version = 0x0100,
178 	},
179 };
180 
181 int __init mk712_init(void)
182 {
183 
184 	if(!request_region(mk712_io, 8, "mk712"))
185 	{
186 		printk(KERN_WARNING "mk712: unable to get IO region\n");
187 		return -ENODEV;
188 	}
189 
190 	outb(0, mk712_io + MK712_CONTROL);
191 
192 	if ((inw(mk712_io + MK712_X) & 0xf000) ||	/* Sanity check */
193 	    (inw(mk712_io + MK712_Y) & 0xf000) ||
194 	    (inw(mk712_io + MK712_STATUS) & 0xf333)) {
195 		printk(KERN_WARNING "mk712: device not present\n");
196 		release_region(mk712_io, 8);
197 		return -ENODEV;
198 	}
199 
200 	if(request_irq(mk712_irq, mk712_interrupt, 0, "mk712", &mk712_dev))
201 	{
202 		printk(KERN_WARNING "mk712: unable to get IRQ\n");
203 		release_region(mk712_io, 8);
204 		return -EBUSY;
205 	}
206 
207 	input_register_device(&mk712_dev);
208 
209 	printk(KERN_INFO "input: ICS MicroClock MK712 TouchScreen at %#x irq %d\n", mk712_io, mk712_irq);
210 
211 	return 0;
212 }
213 
214 static void __exit mk712_exit(void)
215 {
216 	input_unregister_device(&mk712_dev);
217 	free_irq(mk712_irq, &mk712_dev);
218 	release_region(mk712_io, 8);
219 }
220 
221 module_init(mk712_init);
222 module_exit(mk712_exit);
223