xref: /openbmc/linux/drivers/input/serio/q40kbd.c (revision 39b6f3aa)
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/init.h>
34 #include <linux/serio.h>
35 #include <linux/interrupt.h>
36 #include <linux/err.h>
37 #include <linux/bitops.h>
38 #include <linux/platform_device.h>
39 #include <linux/slab.h>
40 
41 #include <asm/io.h>
42 #include <asm/uaccess.h>
43 #include <asm/q40_master.h>
44 #include <asm/irq.h>
45 #include <asm/q40ints.h>
46 
47 #define DRV_NAME	"q40kbd"
48 
49 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
50 MODULE_DESCRIPTION("Q40 PS/2 keyboard controller driver");
51 MODULE_LICENSE("GPL");
52 MODULE_ALIAS("platform:" DRV_NAME);
53 
54 struct q40kbd {
55 	struct serio *port;
56 	spinlock_t lock;
57 };
58 
59 static irqreturn_t q40kbd_interrupt(int irq, void *dev_id)
60 {
61 	struct q40kbd *q40kbd = dev_id;
62 	unsigned long flags;
63 
64 	spin_lock_irqsave(&q40kbd->lock, flags);
65 
66 	if (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG))
67 		serio_interrupt(q40kbd->port, master_inb(KEYCODE_REG), 0);
68 
69 	master_outb(-1, KEYBOARD_UNLOCK_REG);
70 
71 	spin_unlock_irqrestore(&q40kbd->lock, flags);
72 
73 	return IRQ_HANDLED;
74 }
75 
76 /*
77  * q40kbd_flush() flushes all data that may be in the keyboard buffers
78  */
79 
80 static void q40kbd_flush(struct q40kbd *q40kbd)
81 {
82 	int maxread = 100;
83 	unsigned long flags;
84 
85 	spin_lock_irqsave(&q40kbd->lock, flags);
86 
87 	while (maxread-- && (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG)))
88 		master_inb(KEYCODE_REG);
89 
90 	spin_unlock_irqrestore(&q40kbd->lock, flags);
91 }
92 
93 static void q40kbd_stop(void)
94 {
95 	master_outb(0, KEY_IRQ_ENABLE_REG);
96 	master_outb(-1, KEYBOARD_UNLOCK_REG);
97 }
98 
99 /*
100  * q40kbd_open() is called when a port is open by the higher layer.
101  * It allocates the interrupt and enables in in the chip.
102  */
103 
104 static int q40kbd_open(struct serio *port)
105 {
106 	struct q40kbd *q40kbd = port->port_data;
107 
108 	q40kbd_flush(q40kbd);
109 
110 	/* off we go */
111 	master_outb(-1, KEYBOARD_UNLOCK_REG);
112 	master_outb(1, KEY_IRQ_ENABLE_REG);
113 
114 	return 0;
115 }
116 
117 static void q40kbd_close(struct serio *port)
118 {
119 	struct q40kbd *q40kbd = port->port_data;
120 
121 	q40kbd_stop();
122 	q40kbd_flush(q40kbd);
123 }
124 
125 static int q40kbd_probe(struct platform_device *pdev)
126 {
127 	struct q40kbd *q40kbd;
128 	struct serio *port;
129 	int error;
130 
131 	q40kbd = kzalloc(sizeof(struct q40kbd), GFP_KERNEL);
132 	port = kzalloc(sizeof(struct serio), GFP_KERNEL);
133 	if (!q40kbd || !port) {
134 		error = -ENOMEM;
135 		goto err_free_mem;
136 	}
137 
138 	q40kbd->port = port;
139 	spin_lock_init(&q40kbd->lock);
140 
141 	port->id.type = SERIO_8042;
142 	port->open = q40kbd_open;
143 	port->close = q40kbd_close;
144 	port->port_data = q40kbd;
145 	port->dev.parent = &pdev->dev;
146 	strlcpy(port->name, "Q40 Kbd Port", sizeof(port->name));
147 	strlcpy(port->phys, "Q40", sizeof(port->phys));
148 
149 	q40kbd_stop();
150 
151 	error = request_irq(Q40_IRQ_KEYBOARD, q40kbd_interrupt, 0,
152 			    DRV_NAME, q40kbd);
153 	if (error) {
154 		dev_err(&pdev->dev, "Can't get irq %d.\n", Q40_IRQ_KEYBOARD);
155 		goto err_free_mem;
156 	}
157 
158 	serio_register_port(q40kbd->port);
159 
160 	platform_set_drvdata(pdev, q40kbd);
161 	printk(KERN_INFO "serio: Q40 kbd registered\n");
162 
163 	return 0;
164 
165 err_free_mem:
166 	kfree(port);
167 	kfree(q40kbd);
168 	return error;
169 }
170 
171 static int q40kbd_remove(struct platform_device *pdev)
172 {
173 	struct q40kbd *q40kbd = platform_get_drvdata(pdev);
174 
175 	/*
176 	 * q40kbd_close() will be called as part of unregistering
177 	 * and will ensure that IRQ is turned off, so it is safe
178 	 * to unregister port first and free IRQ later.
179 	 */
180 	serio_unregister_port(q40kbd->port);
181 	free_irq(Q40_IRQ_KEYBOARD, q40kbd);
182 	kfree(q40kbd);
183 
184 	platform_set_drvdata(pdev, NULL);
185 	return 0;
186 }
187 
188 static struct platform_driver q40kbd_driver = {
189 	.driver		= {
190 		.name	= "q40kbd",
191 		.owner	= THIS_MODULE,
192 	},
193 	.remove		= q40kbd_remove,
194 };
195 
196 module_platform_driver_probe(q40kbd_driver, q40kbd_probe);
197