rpckbd.c revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 
1/*
2 * $Id: rpckbd.c,v 1.7 2001/09/25 10:12:07 vojtech Exp $
3 *
4 *  Copyright (c) 2000-2001 Vojtech Pavlik
5 *  Copyright (c) 2002 Russell King
6 */
7
8/*
9 * Acorn RiscPC PS/2 keyboard controller driver for Linux/ARM
10 */
11
12/*
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
17 *
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21 * GNU General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 *
27 * Should you need to contact me, the author, you can do so either by
28 * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
29 * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
30 */
31
32#include <linux/module.h>
33#include <linux/interrupt.h>
34#include <linux/init.h>
35#include <linux/serio.h>
36#include <linux/err.h>
37
38#include <asm/irq.h>
39#include <asm/hardware.h>
40#include <asm/io.h>
41#include <asm/hardware/iomd.h>
42#include <asm/system.h>
43
44MODULE_AUTHOR("Vojtech Pavlik, Russell King");
45MODULE_DESCRIPTION("Acorn RiscPC PS/2 keyboard controller driver");
46MODULE_LICENSE("GPL");
47
48static int rpckbd_write(struct serio *port, unsigned char val)
49{
50	while (!(iomd_readb(IOMD_KCTRL) & (1 << 7)))
51		cpu_relax();
52
53	iomd_writeb(val, IOMD_KARTTX);
54
55	return 0;
56}
57
58static irqreturn_t rpckbd_rx(int irq, void *dev_id, struct pt_regs *regs)
59{
60	struct serio *port = dev_id;
61	unsigned int byte;
62	int handled = IRQ_NONE;
63
64	while (iomd_readb(IOMD_KCTRL) & (1 << 5)) {
65		byte = iomd_readb(IOMD_KARTRX);
66
67		serio_interrupt(port, byte, 0, regs);
68		handled = IRQ_HANDLED;
69	}
70	return handled;
71}
72
73static irqreturn_t rpckbd_tx(int irq, void *dev_id, struct pt_regs *regs)
74{
75	return IRQ_HANDLED;
76}
77
78static int rpckbd_open(struct serio *port)
79{
80	/* Reset the keyboard state machine. */
81	iomd_writeb(0, IOMD_KCTRL);
82	iomd_writeb(8, IOMD_KCTRL);
83	iomd_readb(IOMD_KARTRX);
84
85	if (request_irq(IRQ_KEYBOARDRX, rpckbd_rx, 0, "rpckbd", port) != 0) {
86		printk(KERN_ERR "rpckbd.c: Could not allocate keyboard receive IRQ\n");
87		return -EBUSY;
88	}
89
90	if (request_irq(IRQ_KEYBOARDTX, rpckbd_tx, 0, "rpckbd", port) != 0) {
91		printk(KERN_ERR "rpckbd.c: Could not allocate keyboard transmit IRQ\n");
92		free_irq(IRQ_KEYBOARDRX, NULL);
93		return -EBUSY;
94	}
95
96	return 0;
97}
98
99static void rpckbd_close(struct serio *port)
100{
101	free_irq(IRQ_KEYBOARDRX, port);
102	free_irq(IRQ_KEYBOARDTX, port);
103}
104
105/*
106 * Allocate and initialize serio structure for subsequent registration
107 * with serio core.
108 */
109static int __devinit rpckbd_probe(struct device *dev)
110{
111	struct serio *serio;
112
113	serio = kmalloc(sizeof(struct serio), GFP_KERNEL);
114	if (!serio)
115		return -ENOMEM;
116
117	memset(serio, 0, sizeof(struct serio));
118	serio->id.type		= SERIO_8042;
119	serio->write		= rpckbd_write;
120	serio->open		= rpckbd_open;
121	serio->close		= rpckbd_close;
122	serio->dev.parent	= dev;
123	strlcpy(serio->name, "RiscPC PS/2 kbd port", sizeof(serio->name));
124	strlcpy(serio->phys, "rpckbd/serio0", sizeof(serio->phys));
125
126	dev_set_drvdata(dev, serio);
127	serio_register_port(serio);
128	return 0;
129}
130
131static int __devexit rpckbd_remove(struct device *dev)
132{
133	struct serio *serio = dev_get_drvdata(dev);
134	serio_unregister_port(serio);
135	return 0;
136}
137
138static struct device_driver rpckbd_driver = {
139	.name		= "kart",
140	.bus		= &platform_bus_type,
141	.probe		= rpckbd_probe,
142	.remove		= __devexit_p(rpckbd_remove),
143};
144
145static int __init rpckbd_init(void)
146{
147	return driver_register(&rpckbd_driver);
148}
149
150static void __exit rpckbd_exit(void)
151{
152	driver_unregister(&rpckbd_driver);
153}
154
155module_init(rpckbd_init);
156module_exit(rpckbd_exit);
157