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(q40kbd->port, master_inb(KEYCODE_REG), 0);
48
49	master_outb(-1, KEYBOARD_UNLOCK_REG);
50
51	spin_unlock_irqrestore(&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(&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(sizeof(struct q40kbd), GFP_KERNEL);
112	port = kzalloc(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(port->name, "Q40 Kbd Port", sizeof(port->name));
127	strscpy(port->phys, "Q40", sizeof(port->phys));
128
129	q40kbd_stop();
130
131	error = request_irq(Q40_IRQ_KEYBOARD, q40kbd_interrupt, 0,
132			    DRV_NAME, 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, q40kbd);
141	printk(KERN_INFO "serio: Q40 kbd registered\n");
142
143	return 0;
144
145err_free_mem:
146	kfree(port);
147	kfree(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(q40kbd->port);
161	free_irq(Q40_IRQ_KEYBOARD, q40kbd);
162	kfree(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