xref: /openbmc/linux/drivers/input/serio/q40kbd.c (revision e3b9f1e8)
1 /*
2  *  Copyright (c) 2000-2001 Vojtech Pavlik
3  *
4  *  Based on the work of:
5  *	Richard Zidlicky <Richard.Zidlicky@stud.informatik.uni-erlangen.de>
6  */
7 
8 /*
9  * Q40 PS/2 keyboard controller driver for Linux/m68k
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/serio.h>
34 #include <linux/interrupt.h>
35 #include <linux/err.h>
36 #include <linux/bitops.h>
37 #include <linux/platform_device.h>
38 #include <linux/slab.h>
39 
40 #include <asm/io.h>
41 #include <linux/uaccess.h>
42 #include <asm/q40_master.h>
43 #include <asm/irq.h>
44 #include <asm/q40ints.h>
45 
46 #define DRV_NAME	"q40kbd"
47 
48 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
49 MODULE_DESCRIPTION("Q40 PS/2 keyboard controller driver");
50 MODULE_LICENSE("GPL");
51 MODULE_ALIAS("platform:" DRV_NAME);
52 
53 struct q40kbd {
54 	struct serio *port;
55 	spinlock_t lock;
56 };
57 
58 static irqreturn_t q40kbd_interrupt(int irq, void *dev_id)
59 {
60 	struct q40kbd *q40kbd = dev_id;
61 	unsigned long flags;
62 
63 	spin_lock_irqsave(&q40kbd->lock, flags);
64 
65 	if (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG))
66 		serio_interrupt(q40kbd->port, master_inb(KEYCODE_REG), 0);
67 
68 	master_outb(-1, KEYBOARD_UNLOCK_REG);
69 
70 	spin_unlock_irqrestore(&q40kbd->lock, flags);
71 
72 	return IRQ_HANDLED;
73 }
74 
75 /*
76  * q40kbd_flush() flushes all data that may be in the keyboard buffers
77  */
78 
79 static void q40kbd_flush(struct q40kbd *q40kbd)
80 {
81 	int maxread = 100;
82 	unsigned long flags;
83 
84 	spin_lock_irqsave(&q40kbd->lock, flags);
85 
86 	while (maxread-- && (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG)))
87 		master_inb(KEYCODE_REG);
88 
89 	spin_unlock_irqrestore(&q40kbd->lock, flags);
90 }
91 
92 static void q40kbd_stop(void)
93 {
94 	master_outb(0, KEY_IRQ_ENABLE_REG);
95 	master_outb(-1, KEYBOARD_UNLOCK_REG);
96 }
97 
98 /*
99  * q40kbd_open() is called when a port is open by the higher layer.
100  * It allocates the interrupt and enables in in the chip.
101  */
102 
103 static int q40kbd_open(struct serio *port)
104 {
105 	struct q40kbd *q40kbd = port->port_data;
106 
107 	q40kbd_flush(q40kbd);
108 
109 	/* off we go */
110 	master_outb(-1, KEYBOARD_UNLOCK_REG);
111 	master_outb(1, KEY_IRQ_ENABLE_REG);
112 
113 	return 0;
114 }
115 
116 static void q40kbd_close(struct serio *port)
117 {
118 	struct q40kbd *q40kbd = port->port_data;
119 
120 	q40kbd_stop();
121 	q40kbd_flush(q40kbd);
122 }
123 
124 static int q40kbd_probe(struct platform_device *pdev)
125 {
126 	struct q40kbd *q40kbd;
127 	struct serio *port;
128 	int error;
129 
130 	q40kbd = kzalloc(sizeof(struct q40kbd), GFP_KERNEL);
131 	port = kzalloc(sizeof(struct serio), GFP_KERNEL);
132 	if (!q40kbd || !port) {
133 		error = -ENOMEM;
134 		goto err_free_mem;
135 	}
136 
137 	q40kbd->port = port;
138 	spin_lock_init(&q40kbd->lock);
139 
140 	port->id.type = SERIO_8042;
141 	port->open = q40kbd_open;
142 	port->close = q40kbd_close;
143 	port->port_data = q40kbd;
144 	port->dev.parent = &pdev->dev;
145 	strlcpy(port->name, "Q40 Kbd Port", sizeof(port->name));
146 	strlcpy(port->phys, "Q40", sizeof(port->phys));
147 
148 	q40kbd_stop();
149 
150 	error = request_irq(Q40_IRQ_KEYBOARD, q40kbd_interrupt, 0,
151 			    DRV_NAME, q40kbd);
152 	if (error) {
153 		dev_err(&pdev->dev, "Can't get irq %d.\n", Q40_IRQ_KEYBOARD);
154 		goto err_free_mem;
155 	}
156 
157 	serio_register_port(q40kbd->port);
158 
159 	platform_set_drvdata(pdev, q40kbd);
160 	printk(KERN_INFO "serio: Q40 kbd registered\n");
161 
162 	return 0;
163 
164 err_free_mem:
165 	kfree(port);
166 	kfree(q40kbd);
167 	return error;
168 }
169 
170 static int q40kbd_remove(struct platform_device *pdev)
171 {
172 	struct q40kbd *q40kbd = platform_get_drvdata(pdev);
173 
174 	/*
175 	 * q40kbd_close() will be called as part of unregistering
176 	 * and will ensure that IRQ is turned off, so it is safe
177 	 * to unregister port first and free IRQ later.
178 	 */
179 	serio_unregister_port(q40kbd->port);
180 	free_irq(Q40_IRQ_KEYBOARD, q40kbd);
181 	kfree(q40kbd);
182 
183 	return 0;
184 }
185 
186 static struct platform_driver q40kbd_driver = {
187 	.driver		= {
188 		.name	= "q40kbd",
189 	},
190 	.remove		= q40kbd_remove,
191 };
192 
193 module_platform_driver_probe(q40kbd_driver, q40kbd_probe);
194