1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * SGI O2 MACE PS2 controller driver for linux
4 *
5 * Copyright (C) 2002 Vivien Chappelier
6 */
7#include <linux/module.h>
8#include <linux/init.h>
9#include <linux/serio.h>
10#include <linux/errno.h>
11#include <linux/interrupt.h>
12#include <linux/ioport.h>
13#include <linux/delay.h>
14#include <linux/platform_device.h>
15#include <linux/slab.h>
16#include <linux/spinlock.h>
17#include <linux/err.h>
18
19#include <asm/io.h>
20#include <asm/irq.h>
21#include <asm/ip32/mace.h>
22#include <asm/ip32/ip32_ints.h>
23
24MODULE_AUTHOR("Vivien Chappelier <vivien.chappelier@linux-mips.org");
25MODULE_DESCRIPTION("SGI O2 MACE PS2 controller driver");
26MODULE_LICENSE("GPL");
27
28#define MACE_PS2_TIMEOUT 10000 /* in 50us unit */
29
30#define PS2_STATUS_CLOCK_SIGNAL  BIT(0) /* external clock signal */
31#define PS2_STATUS_CLOCK_INHIBIT BIT(1) /* clken output signal */
32#define PS2_STATUS_TX_INPROGRESS BIT(2) /* transmission in progress */
33#define PS2_STATUS_TX_EMPTY      BIT(3) /* empty transmit buffer */
34#define PS2_STATUS_RX_FULL       BIT(4) /* full receive buffer */
35#define PS2_STATUS_RX_INPROGRESS BIT(5) /* reception in progress */
36#define PS2_STATUS_ERROR_PARITY  BIT(6) /* parity error */
37#define PS2_STATUS_ERROR_FRAMING BIT(7) /* framing error */
38
39#define PS2_CONTROL_TX_CLOCK_DISABLE BIT(0) /* inhibit clock signal after TX */
40#define PS2_CONTROL_TX_ENABLE        BIT(1) /* transmit enable */
41#define PS2_CONTROL_TX_INT_ENABLE    BIT(2) /* enable transmit interrupt */
42#define PS2_CONTROL_RX_INT_ENABLE    BIT(3) /* enable receive interrupt */
43#define PS2_CONTROL_RX_CLOCK_ENABLE  BIT(4) /* pause reception if set to 0 */
44#define PS2_CONTROL_RESET            BIT(5) /* reset */
45
46struct maceps2_data {
47	struct mace_ps2port *port;
48	int irq;
49};
50
51static struct maceps2_data port_data[2];
52static struct serio *maceps2_port[2];
53static struct platform_device *maceps2_device;
54
55static int maceps2_write(struct serio *dev, unsigned char val)
56{
57	struct mace_ps2port *port = ((struct maceps2_data *)dev->port_data)->port;
58	unsigned int timeout = MACE_PS2_TIMEOUT;
59
60	do {
61		if (port->status & PS2_STATUS_TX_EMPTY) {
62			port->tx = val;
63			return 0;
64		}
65		udelay(50);
66	} while (timeout--);
67
68	return -1;
69}
70
71static irqreturn_t maceps2_interrupt(int irq, void *dev_id)
72{
73	struct serio *dev = dev_id;
74	struct mace_ps2port *port = ((struct maceps2_data *)dev->port_data)->port;
75	unsigned long byte;
76
77	if (port->status & PS2_STATUS_RX_FULL) {
78		byte = port->rx;
79		serio_interrupt(dev, byte & 0xff, 0);
80        }
81
82	return IRQ_HANDLED;
83}
84
85static int maceps2_open(struct serio *dev)
86{
87	struct maceps2_data *data = (struct maceps2_data *)dev->port_data;
88
89	if (request_irq(data->irq, maceps2_interrupt, 0, "PS2 port", dev)) {
90		printk(KERN_ERR "Could not allocate PS/2 IRQ\n");
91		return -EBUSY;
92	}
93
94	/* Reset port */
95	data->port->control = PS2_CONTROL_TX_CLOCK_DISABLE | PS2_CONTROL_RESET;
96	udelay(100);
97
98        /* Enable interrupts */
99	data->port->control = PS2_CONTROL_RX_CLOCK_ENABLE |
100			      PS2_CONTROL_TX_ENABLE |
101			      PS2_CONTROL_RX_INT_ENABLE;
102
103	return 0;
104}
105
106static void maceps2_close(struct serio *dev)
107{
108	struct maceps2_data *data = (struct maceps2_data *)dev->port_data;
109
110	data->port->control = PS2_CONTROL_TX_CLOCK_DISABLE | PS2_CONTROL_RESET;
111	udelay(100);
112	free_irq(data->irq, dev);
113}
114
115
116static struct serio *maceps2_allocate_port(int idx)
117{
118	struct serio *serio;
119
120	serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
121	if (serio) {
122		serio->id.type		= SERIO_8042;
123		serio->write		= maceps2_write;
124		serio->open		= maceps2_open;
125		serio->close		= maceps2_close;
126		snprintf(serio->name, sizeof(serio->name), "MACE PS/2 port%d", idx);
127		snprintf(serio->phys, sizeof(serio->phys), "mace/serio%d", idx);
128		serio->port_data	= &port_data[idx];
129		serio->dev.parent	= &maceps2_device->dev;
130	}
131
132	return serio;
133}
134
135static int maceps2_probe(struct platform_device *dev)
136{
137	maceps2_port[0] = maceps2_allocate_port(0);
138	maceps2_port[1] = maceps2_allocate_port(1);
139	if (!maceps2_port[0] || !maceps2_port[1]) {
140		kfree(maceps2_port[0]);
141		kfree(maceps2_port[1]);
142		return -ENOMEM;
143	}
144
145	serio_register_port(maceps2_port[0]);
146	serio_register_port(maceps2_port[1]);
147
148	return 0;
149}
150
151static int maceps2_remove(struct platform_device *dev)
152{
153	serio_unregister_port(maceps2_port[0]);
154	serio_unregister_port(maceps2_port[1]);
155
156	return 0;
157}
158
159static struct platform_driver maceps2_driver = {
160	.driver		= {
161		.name	= "maceps2",
162	},
163	.probe		= maceps2_probe,
164	.remove		= maceps2_remove,
165};
166
167static int __init maceps2_init(void)
168{
169	int error;
170
171	error = platform_driver_register(&maceps2_driver);
172	if (error)
173		return error;
174
175	maceps2_device = platform_device_alloc("maceps2", -1);
176	if (!maceps2_device) {
177		error = -ENOMEM;
178		goto err_unregister_driver;
179	}
180
181	port_data[0].port = &mace->perif.ps2.keyb;
182	port_data[0].irq  = MACEISA_KEYB_IRQ;
183	port_data[1].port = &mace->perif.ps2.mouse;
184	port_data[1].irq  = MACEISA_MOUSE_IRQ;
185
186	error = platform_device_add(maceps2_device);
187	if (error)
188		goto err_free_device;
189
190	return 0;
191
192 err_free_device:
193	platform_device_put(maceps2_device);
194 err_unregister_driver:
195	platform_driver_unregister(&maceps2_driver);
196	return error;
197}
198
199static void __exit maceps2_exit(void)
200{
201	platform_device_unregister(maceps2_device);
202	platform_driver_unregister(&maceps2_driver);
203}
204
205module_init(maceps2_init);
206module_exit(maceps2_exit);
207