q40kbd.c

  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
 43	guard(spinlock_irqsave)(&q40kbd->lock);
 44
 45	if (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG))
 46		serio_interrupt(q40kbd->port, master_inb(KEYCODE_REG), 0);
 47
 48	master_outb(-1, KEYBOARD_UNLOCK_REG);
 49
 50	return IRQ_HANDLED;
 51}
 52
 53/*
 54 * q40kbd_flush() flushes all data that may be in the keyboard buffers
 55 */
 56
 57static void q40kbd_flush(struct q40kbd *q40kbd)
 58{
 59	int maxread = 100;
 60
 61	guard(spinlock_irqsave)(&q40kbd->lock);
 62
 63	while (maxread-- && (Q40_IRQ_KEYB_MASK & master_inb(INTERRUPT_REG)))
 64		master_inb(KEYCODE_REG);
 65}
 66
 67static void q40kbd_stop(void)
 68{
 69	master_outb(0, KEY_IRQ_ENABLE_REG);
 70	master_outb(-1, KEYBOARD_UNLOCK_REG);
 71}
 72
 73/*
 74 * q40kbd_open() is called when a port is open by the higher layer.
 75 * It allocates the interrupt and enables in in the chip.
 76 */
 77
 78static int q40kbd_open(struct serio *port)
 79{
 80	struct q40kbd *q40kbd = port->port_data;
 81
 82	q40kbd_flush(q40kbd);
 83
 84	/* off we go */
 85	master_outb(-1, KEYBOARD_UNLOCK_REG);
 86	master_outb(1, KEY_IRQ_ENABLE_REG);
 87
 88	return 0;
 89}
 90
 91static void q40kbd_close(struct serio *port)
 92{
 93	struct q40kbd *q40kbd = port->port_data;
 94
 95	q40kbd_stop();
 96	q40kbd_flush(q40kbd);
 97}
 98
 99static int q40kbd_probe(struct platform_device *pdev)
100{
101	struct q40kbd *q40kbd;
102	struct serio *port;
103	int error;
104
105	q40kbd = kzalloc(sizeof(*q40kbd), GFP_KERNEL);
106	port = kzalloc(sizeof(*port), GFP_KERNEL);
107	if (!q40kbd || !port) {
108		error = -ENOMEM;
109		goto err_free_mem;
110	}
111
112	q40kbd->port = port;
113	spin_lock_init(&q40kbd->lock);
114
115	port->id.type = SERIO_8042;
116	port->open = q40kbd_open;
117	port->close = q40kbd_close;
118	port->port_data = q40kbd;
119	port->dev.parent = &pdev->dev;
120	strscpy(port->name, "Q40 Kbd Port", sizeof(port->name));
121	strscpy(port->phys, "Q40", sizeof(port->phys));
122
123	q40kbd_stop();
124
125	error = request_irq(Q40_IRQ_KEYBOARD, q40kbd_interrupt, 0,
126			    DRV_NAME, q40kbd);
127	if (error) {
128		dev_err(&pdev->dev, "Can't get irq %d.\n", Q40_IRQ_KEYBOARD);
129		goto err_free_mem;
130	}
131
132	serio_register_port(q40kbd->port);
133
134	platform_set_drvdata(pdev, q40kbd);
135	printk(KERN_INFO "serio: Q40 kbd registered\n");
136
137	return 0;
138
139err_free_mem:
140	kfree(port);
141	kfree(q40kbd);
142	return error;
143}
144
145static void q40kbd_remove(struct platform_device *pdev)
146{
147	struct q40kbd *q40kbd = platform_get_drvdata(pdev);
148
149	/*
150	 * q40kbd_close() will be called as part of unregistering
151	 * and will ensure that IRQ is turned off, so it is safe
152	 * to unregister port first and free IRQ later.
153	 */
154	serio_unregister_port(q40kbd->port);
155	free_irq(Q40_IRQ_KEYBOARD, q40kbd);
156	kfree(q40kbd);
157}
158
159static struct platform_driver q40kbd_driver = {
160	.driver		= {
161		.name	= "q40kbd",
162	},
163	.remove		= q40kbd_remove,
164};
165
166module_platform_driver_probe(q40kbd_driver, q40kbd_probe);