xref: /openbmc/linux/drivers/input/serio/maceps2.c (revision 293d5b43)
1 /*
2  * SGI O2 MACE PS2 controller driver for linux
3  *
4  * Copyright (C) 2002 Vivien Chappelier
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation
9  */
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/serio.h>
13 #include <linux/errno.h>
14 #include <linux/interrupt.h>
15 #include <linux/ioport.h>
16 #include <linux/delay.h>
17 #include <linux/platform_device.h>
18 #include <linux/slab.h>
19 #include <linux/spinlock.h>
20 #include <linux/err.h>
21 
22 #include <asm/io.h>
23 #include <asm/irq.h>
24 #include <asm/ip32/mace.h>
25 #include <asm/ip32/ip32_ints.h>
26 
27 MODULE_AUTHOR("Vivien Chappelier <vivien.chappelier@linux-mips.org");
28 MODULE_DESCRIPTION("SGI O2 MACE PS2 controller driver");
29 MODULE_LICENSE("GPL");
30 
31 #define MACE_PS2_TIMEOUT 10000 /* in 50us unit */
32 
33 #define PS2_STATUS_CLOCK_SIGNAL  BIT(0) /* external clock signal */
34 #define PS2_STATUS_CLOCK_INHIBIT BIT(1) /* clken output signal */
35 #define PS2_STATUS_TX_INPROGRESS BIT(2) /* transmission in progress */
36 #define PS2_STATUS_TX_EMPTY      BIT(3) /* empty transmit buffer */
37 #define PS2_STATUS_RX_FULL       BIT(4) /* full receive buffer */
38 #define PS2_STATUS_RX_INPROGRESS BIT(5) /* reception in progress */
39 #define PS2_STATUS_ERROR_PARITY  BIT(6) /* parity error */
40 #define PS2_STATUS_ERROR_FRAMING BIT(7) /* framing error */
41 
42 #define PS2_CONTROL_TX_CLOCK_DISABLE BIT(0) /* inhibit clock signal after TX */
43 #define PS2_CONTROL_TX_ENABLE        BIT(1) /* transmit enable */
44 #define PS2_CONTROL_TX_INT_ENABLE    BIT(2) /* enable transmit interrupt */
45 #define PS2_CONTROL_RX_INT_ENABLE    BIT(3) /* enable receive interrupt */
46 #define PS2_CONTROL_RX_CLOCK_ENABLE  BIT(4) /* pause reception if set to 0 */
47 #define PS2_CONTROL_RESET            BIT(5) /* reset */
48 
49 struct maceps2_data {
50 	struct mace_ps2port *port;
51 	int irq;
52 };
53 
54 static struct maceps2_data port_data[2];
55 static struct serio *maceps2_port[2];
56 static struct platform_device *maceps2_device;
57 
58 static int maceps2_write(struct serio *dev, unsigned char val)
59 {
60 	struct mace_ps2port *port = ((struct maceps2_data *)dev->port_data)->port;
61 	unsigned int timeout = MACE_PS2_TIMEOUT;
62 
63 	do {
64 		if (port->status & PS2_STATUS_TX_EMPTY) {
65 			port->tx = val;
66 			return 0;
67 		}
68 		udelay(50);
69 	} while (timeout--);
70 
71 	return -1;
72 }
73 
74 static irqreturn_t maceps2_interrupt(int irq, void *dev_id)
75 {
76 	struct serio *dev = dev_id;
77 	struct mace_ps2port *port = ((struct maceps2_data *)dev->port_data)->port;
78 	unsigned long byte;
79 
80 	if (port->status & PS2_STATUS_RX_FULL) {
81 		byte = port->rx;
82 		serio_interrupt(dev, byte & 0xff, 0);
83         }
84 
85 	return IRQ_HANDLED;
86 }
87 
88 static int maceps2_open(struct serio *dev)
89 {
90 	struct maceps2_data *data = (struct maceps2_data *)dev->port_data;
91 
92 	if (request_irq(data->irq, maceps2_interrupt, 0, "PS2 port", dev)) {
93 		printk(KERN_ERR "Could not allocate PS/2 IRQ\n");
94 		return -EBUSY;
95 	}
96 
97 	/* Reset port */
98 	data->port->control = PS2_CONTROL_TX_CLOCK_DISABLE | PS2_CONTROL_RESET;
99 	udelay(100);
100 
101         /* Enable interrupts */
102 	data->port->control = PS2_CONTROL_RX_CLOCK_ENABLE |
103 			      PS2_CONTROL_TX_ENABLE |
104 			      PS2_CONTROL_RX_INT_ENABLE;
105 
106 	return 0;
107 }
108 
109 static void maceps2_close(struct serio *dev)
110 {
111 	struct maceps2_data *data = (struct maceps2_data *)dev->port_data;
112 
113 	data->port->control = PS2_CONTROL_TX_CLOCK_DISABLE | PS2_CONTROL_RESET;
114 	udelay(100);
115 	free_irq(data->irq, dev);
116 }
117 
118 
119 static struct serio *maceps2_allocate_port(int idx)
120 {
121 	struct serio *serio;
122 
123 	serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
124 	if (serio) {
125 		serio->id.type		= SERIO_8042;
126 		serio->write		= maceps2_write;
127 		serio->open		= maceps2_open;
128 		serio->close		= maceps2_close;
129 		snprintf(serio->name, sizeof(serio->name), "MACE PS/2 port%d", idx);
130 		snprintf(serio->phys, sizeof(serio->phys), "mace/serio%d", idx);
131 		serio->port_data	= &port_data[idx];
132 		serio->dev.parent	= &maceps2_device->dev;
133 	}
134 
135 	return serio;
136 }
137 
138 static int maceps2_probe(struct platform_device *dev)
139 {
140 	maceps2_port[0] = maceps2_allocate_port(0);
141 	maceps2_port[1] = maceps2_allocate_port(1);
142 	if (!maceps2_port[0] || !maceps2_port[1]) {
143 		kfree(maceps2_port[0]);
144 		kfree(maceps2_port[1]);
145 		return -ENOMEM;
146 	}
147 
148 	serio_register_port(maceps2_port[0]);
149 	serio_register_port(maceps2_port[1]);
150 
151 	return 0;
152 }
153 
154 static int maceps2_remove(struct platform_device *dev)
155 {
156 	serio_unregister_port(maceps2_port[0]);
157 	serio_unregister_port(maceps2_port[1]);
158 
159 	return 0;
160 }
161 
162 static struct platform_driver maceps2_driver = {
163 	.driver		= {
164 		.name	= "maceps2",
165 	},
166 	.probe		= maceps2_probe,
167 	.remove		= maceps2_remove,
168 };
169 
170 static int __init maceps2_init(void)
171 {
172 	int error;
173 
174 	error = platform_driver_register(&maceps2_driver);
175 	if (error)
176 		return error;
177 
178 	maceps2_device = platform_device_alloc("maceps2", -1);
179 	if (!maceps2_device) {
180 		error = -ENOMEM;
181 		goto err_unregister_driver;
182 	}
183 
184 	port_data[0].port = &mace->perif.ps2.keyb;
185 	port_data[0].irq  = MACEISA_KEYB_IRQ;
186 	port_data[1].port = &mace->perif.ps2.mouse;
187 	port_data[1].irq  = MACEISA_MOUSE_IRQ;
188 
189 	error = platform_device_add(maceps2_device);
190 	if (error)
191 		goto err_free_device;
192 
193 	return 0;
194 
195  err_free_device:
196 	platform_device_put(maceps2_device);
197  err_unregister_driver:
198 	platform_driver_unregister(&maceps2_driver);
199 	return error;
200 }
201 
202 static void __exit maceps2_exit(void)
203 {
204 	platform_device_unregister(maceps2_device);
205 	platform_driver_unregister(&maceps2_driver);
206 }
207 
208 module_init(maceps2_init);
209 module_exit(maceps2_exit);
210