1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (c) 2000-2001 Vojtech Pavlik
4 *  Copyright (c) 2002 Russell King
5 */
6
7/*
8 * Acorn RiscPC PS/2 keyboard controller driver for Linux/ARM
9 */
10
11/*
12 */
13
14#include <linux/module.h>
15#include <linux/interrupt.h>
16#include <linux/serio.h>
17#include <linux/err.h>
18#include <linux/platform_device.h>
19#include <linux/io.h>
20#include <linux/slab.h>
21
22#include <mach/hardware.h>
23#include <asm/hardware/iomd.h>
24
25MODULE_AUTHOR("Vojtech Pavlik, Russell King");
26MODULE_DESCRIPTION("Acorn RiscPC PS/2 keyboard controller driver");
27MODULE_LICENSE("GPL");
28MODULE_ALIAS("platform:kart");
29
30struct rpckbd_data {
31	int tx_irq;
32	int rx_irq;
33};
34
35static int rpckbd_write(struct serio *port, unsigned char val)
36{
37	while (!(iomd_readb(IOMD_KCTRL) & (1 << 7)))
38		cpu_relax();
39
40	iomd_writeb(val, IOMD_KARTTX);
41
42	return 0;
43}
44
45static irqreturn_t rpckbd_rx(int irq, void *dev_id)
46{
47	struct serio *port = dev_id;
48	unsigned int byte;
49	int handled = IRQ_NONE;
50
51	while (iomd_readb(IOMD_KCTRL) & (1 << 5)) {
52		byte = iomd_readb(IOMD_KARTRX);
53
54		serio_interrupt(port, byte, 0);
55		handled = IRQ_HANDLED;
56	}
57	return handled;
58}
59
60static irqreturn_t rpckbd_tx(int irq, void *dev_id)
61{
62	return IRQ_HANDLED;
63}
64
65static int rpckbd_open(struct serio *port)
66{
67	struct rpckbd_data *rpckbd = port->port_data;
68
69	/* Reset the keyboard state machine. */
70	iomd_writeb(0, IOMD_KCTRL);
71	iomd_writeb(8, IOMD_KCTRL);
72	iomd_readb(IOMD_KARTRX);
73
74	if (request_irq(rpckbd->rx_irq, rpckbd_rx, 0, "rpckbd", port) != 0) {
75		printk(KERN_ERR "rpckbd.c: Could not allocate keyboard receive IRQ\n");
76		return -EBUSY;
77	}
78
79	if (request_irq(rpckbd->tx_irq, rpckbd_tx, 0, "rpckbd", port) != 0) {
80		printk(KERN_ERR "rpckbd.c: Could not allocate keyboard transmit IRQ\n");
81		free_irq(rpckbd->rx_irq, port);
82		return -EBUSY;
83	}
84
85	return 0;
86}
87
88static void rpckbd_close(struct serio *port)
89{
90	struct rpckbd_data *rpckbd = port->port_data;
91
92	free_irq(rpckbd->rx_irq, port);
93	free_irq(rpckbd->tx_irq, port);
94}
95
96/*
97 * Allocate and initialize serio structure for subsequent registration
98 * with serio core.
99 */
100static int rpckbd_probe(struct platform_device *dev)
101{
102	struct rpckbd_data *rpckbd;
103	struct serio *serio;
104	int tx_irq, rx_irq;
105
106	rx_irq = platform_get_irq(dev, 0);
107	if (rx_irq <= 0)
108		return rx_irq < 0 ? rx_irq : -ENXIO;
109
110	tx_irq = platform_get_irq(dev, 1);
111	if (tx_irq <= 0)
112		return tx_irq < 0 ? tx_irq : -ENXIO;
113
114	serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
115	rpckbd = kzalloc(sizeof(*rpckbd), GFP_KERNEL);
116	if (!serio || !rpckbd) {
117		kfree(rpckbd);
118		kfree(serio);
119		return -ENOMEM;
120	}
121
122	rpckbd->rx_irq = rx_irq;
123	rpckbd->tx_irq = tx_irq;
124
125	serio->id.type		= SERIO_8042;
126	serio->write		= rpckbd_write;
127	serio->open		= rpckbd_open;
128	serio->close		= rpckbd_close;
129	serio->dev.parent	= &dev->dev;
130	serio->port_data	= rpckbd;
131	strlcpy(serio->name, "RiscPC PS/2 kbd port", sizeof(serio->name));
132	strlcpy(serio->phys, "rpckbd/serio0", sizeof(serio->phys));
133
134	platform_set_drvdata(dev, serio);
135	serio_register_port(serio);
136	return 0;
137}
138
139static int rpckbd_remove(struct platform_device *dev)
140{
141	struct serio *serio = platform_get_drvdata(dev);
142	struct rpckbd_data *rpckbd = serio->port_data;
143
144	serio_unregister_port(serio);
145	kfree(rpckbd);
146
147	return 0;
148}
149
150static struct platform_driver rpckbd_driver = {
151	.probe		= rpckbd_probe,
152	.remove		= rpckbd_remove,
153	.driver		= {
154		.name	= "kart",
155	},
156};
157module_platform_driver(rpckbd_driver);
158