1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) 2000-2001 Vojtech Pavlik
4 *
5 * Based on the work of:
6 * Richard Zidlicky <Richard.Zidlicky@stud.informatik.uni-erlangen.de>
7 */
8
9/*
10 * Q40 PS/2 keyboard controller driver for Linux/m68k
11 */
12
13#include <linux/module.h>
14#include <linux/serio.h>
15#include <linux/interrupt.h>
16#include <linux/err.h>
17#include <linux/bitops.h>
18#include <linux/platform_device.h>
19#include <linux/slab.h>
20
21#include <asm/io.h>
22#include <linux/uaccess.h>
23#include <asm/q40_master.h>
24#include <asm/irq.h>
25#include <asm/q40ints.h>
26
27#define DRV_NAME "q40kbd"
28
29MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
30MODULE_DESCRIPTION("Q40 PS/2 keyboard controller driver");
31MODULE_LICENSE("GPL");
32MODULE_ALIAS("platform:" DRV_NAME);
33
34struct q40kbd {
35 struct serio *port;
36 spinlock_t lock;
37};
38
39static irqreturn_t q40kbd_interrupt(int irq, void *dev_id)
40{
41 struct q40kbd *q40kbd = dev_id;
42 unsigned long flags;
43
44 spin_lock_irqsave(&q40kbd->lock, flags);
45
46 if (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG))
47 serio_interrupt(serio: q40kbd->port, data: master_inb(KEYCODE_REG), flags: 0);
48
49 master_outb(-1, KEYBOARD_UNLOCK_REG);
50
51 spin_unlock_irqrestore(lock: &q40kbd->lock, flags);
52
53 return IRQ_HANDLED;
54}
55
56/*
57 * q40kbd_flush() flushes all data that may be in the keyboard buffers
58 */
59
60static void q40kbd_flush(struct q40kbd *q40kbd)
61{
62 int maxread = 100;
63 unsigned long flags;
64
65 spin_lock_irqsave(&q40kbd->lock, flags);
66
67 while (maxread-- && (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG)))
68 master_inb(KEYCODE_REG);
69
70 spin_unlock_irqrestore(lock: &q40kbd->lock, flags);
71}
72
73static void q40kbd_stop(void)
74{
75 master_outb(0, KEY_IRQ_ENABLE_REG);
76 master_outb(-1, KEYBOARD_UNLOCK_REG);
77}
78
79/*
80 * q40kbd_open() is called when a port is open by the higher layer.
81 * It allocates the interrupt and enables in in the chip.
82 */
83
84static int q40kbd_open(struct serio *port)
85{
86 struct q40kbd *q40kbd = port->port_data;
87
88 q40kbd_flush(q40kbd);
89
90 /* off we go */
91 master_outb(-1, KEYBOARD_UNLOCK_REG);
92 master_outb(1, KEY_IRQ_ENABLE_REG);
93
94 return 0;
95}
96
97static void q40kbd_close(struct serio *port)
98{
99 struct q40kbd *q40kbd = port->port_data;
100
101 q40kbd_stop();
102 q40kbd_flush(q40kbd);
103}
104
105static int q40kbd_probe(struct platform_device *pdev)
106{
107 struct q40kbd *q40kbd;
108 struct serio *port;
109 int error;
110
111 q40kbd = kzalloc(size: sizeof(struct q40kbd), GFP_KERNEL);
112 port = kzalloc(size: sizeof(struct serio), GFP_KERNEL);
113 if (!q40kbd || !port) {
114 error = -ENOMEM;
115 goto err_free_mem;
116 }
117
118 q40kbd->port = port;
119 spin_lock_init(&q40kbd->lock);
120
121 port->id.type = SERIO_8042;
122 port->open = q40kbd_open;
123 port->close = q40kbd_close;
124 port->port_data = q40kbd;
125 port->dev.parent = &pdev->dev;
126 strscpy(p: port->name, q: "Q40 Kbd Port", size: sizeof(port->name));
127 strscpy(p: port->phys, q: "Q40", size: sizeof(port->phys));
128
129 q40kbd_stop();
130
131 error = request_irq(irq: Q40_IRQ_KEYBOARD, handler: q40kbd_interrupt, flags: 0,
132 DRV_NAME, dev: q40kbd);
133 if (error) {
134 dev_err(&pdev->dev, "Can't get irq %d.\n", Q40_IRQ_KEYBOARD);
135 goto err_free_mem;
136 }
137
138 serio_register_port(q40kbd->port);
139
140 platform_set_drvdata(pdev, data: q40kbd);
141 printk(KERN_INFO "serio: Q40 kbd registered\n");
142
143 return 0;
144
145err_free_mem:
146 kfree(objp: port);
147 kfree(objp: q40kbd);
148 return error;
149}
150
151static int q40kbd_remove(struct platform_device *pdev)
152{
153 struct q40kbd *q40kbd = platform_get_drvdata(pdev);
154
155 /*
156 * q40kbd_close() will be called as part of unregistering
157 * and will ensure that IRQ is turned off, so it is safe
158 * to unregister port first and free IRQ later.
159 */
160 serio_unregister_port(serio: q40kbd->port);
161 free_irq(Q40_IRQ_KEYBOARD, q40kbd);
162 kfree(objp: q40kbd);
163
164 return 0;
165}
166
167static struct platform_driver q40kbd_driver = {
168 .driver = {
169 .name = "q40kbd",
170 },
171 .remove = q40kbd_remove,
172};
173
174module_platform_driver_probe(q40kbd_driver, q40kbd_probe);
175

source code of linux/drivers/input/serio/q40kbd.c