xref: /openbmc/linux/drivers/input/serio/maceps2.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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/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/system.h>
25 #include <asm/ip32/mace.h>
26 #include <asm/ip32/ip32_ints.h>
27 
28 MODULE_AUTHOR("Vivien Chappelier <vivien.chappelier@linux-mips.org");
29 MODULE_DESCRIPTION("SGI O2 MACE PS2 controller driver");
30 MODULE_LICENSE("GPL");
31 
32 #define MACE_PS2_TIMEOUT 10000 /* in 50us unit */
33 
34 #define PS2_STATUS_CLOCK_SIGNAL  BIT(0) /* external clock signal */
35 #define PS2_STATUS_CLOCK_INHIBIT BIT(1) /* clken output signal */
36 #define PS2_STATUS_TX_INPROGRESS BIT(2) /* transmission in progress */
37 #define PS2_STATUS_TX_EMPTY      BIT(3) /* empty transmit buffer */
38 #define PS2_STATUS_RX_FULL       BIT(4) /* full receive buffer */
39 #define PS2_STATUS_RX_INPROGRESS BIT(5) /* reception in progress */
40 #define PS2_STATUS_ERROR_PARITY  BIT(6) /* parity error */
41 #define PS2_STATUS_ERROR_FRAMING BIT(7) /* framing error */
42 
43 #define PS2_CONTROL_TX_CLOCK_DISABLE BIT(0) /* inhibit clock signal after TX */
44 #define PS2_CONTROL_TX_ENABLE        BIT(1) /* transmit enable */
45 #define PS2_CONTROL_TX_INT_ENABLE    BIT(2) /* enable transmit interrupt */
46 #define PS2_CONTROL_RX_INT_ENABLE    BIT(3) /* enable receive interrupt */
47 #define PS2_CONTROL_RX_CLOCK_ENABLE  BIT(4) /* pause reception if set to 0 */
48 #define PS2_CONTROL_RESET            BIT(5) /* reset */
49 
50 struct maceps2_data {
51 	struct mace_ps2port *port;
52 	int irq;
53 };
54 
55 static struct maceps2_data port_data[2];
56 static struct serio *maceps2_port[2];
57 static struct platform_device *maceps2_device;
58 
59 static int maceps2_write(struct serio *dev, unsigned char val)
60 {
61 	struct mace_ps2port *port = ((struct maceps2_data *)dev->port_data)->port;
62 	unsigned int timeout = MACE_PS2_TIMEOUT;
63 
64 	do {
65 		if (port->status & PS2_STATUS_TX_EMPTY) {
66 			port->tx = val;
67 			return 0;
68 		}
69 		udelay(50);
70 	} while (timeout--);
71 
72 	return -1;
73 }
74 
75 static irqreturn_t maceps2_interrupt(int irq, void *dev_id,
76 				     struct pt_regs *regs)
77 {
78 	struct serio *dev = dev_id;
79 	struct mace_ps2port *port = ((struct maceps2_data *)dev->port_data)->port;
80 	unsigned long byte;
81 
82 	if (port->status & PS2_STATUS_RX_FULL) {
83 		byte = port->rx;
84 		serio_interrupt(dev, byte & 0xff, 0, regs);
85         }
86 
87 	return IRQ_HANDLED;
88 }
89 
90 static int maceps2_open(struct serio *dev)
91 {
92 	struct maceps2_data *data = (struct maceps2_data *)dev->port_data;
93 
94 	if (request_irq(data->irq, maceps2_interrupt, 0, "PS2 port", dev)) {
95 		printk(KERN_ERR "Could not allocate PS/2 IRQ\n");
96 		return -EBUSY;
97 	}
98 
99 	/* Reset port */
100 	data->port->control = PS2_CONTROL_TX_CLOCK_DISABLE | PS2_CONTROL_RESET;
101 	udelay(100);
102 
103         /* Enable interrupts */
104 	data->port->control = PS2_CONTROL_RX_CLOCK_ENABLE |
105 			      PS2_CONTROL_TX_ENABLE |
106 			      PS2_CONTROL_RX_INT_ENABLE;
107 
108 	return 0;
109 }
110 
111 static void maceps2_close(struct serio *dev)
112 {
113 	struct maceps2_data *data = (struct maceps2_data *)dev->port_data;
114 
115 	data->port->control = PS2_CONTROL_TX_CLOCK_DISABLE | PS2_CONTROL_RESET;
116 	udelay(100);
117 	free_irq(data->irq, dev);
118 }
119 
120 
121 static struct serio * __init maceps2_allocate_port(int idx)
122 {
123 	struct serio *serio;
124 
125 	serio = kmalloc(sizeof(struct serio), GFP_KERNEL);
126 	if (serio) {
127 		memset(serio, 0, sizeof(struct serio));
128 		serio->id.type		= SERIO_8042;
129 		serio->write		= maceps2_write;
130 		serio->open		= maceps2_open;
131 		serio->close		= maceps2_close;
132 		snprintf(serio->name, sizeof(serio->name), "MACE PS/2 port%d", idx);
133 		snprintf(serio->phys, sizeof(serio->phys), "mace/serio%d", idx);
134 		serio->port_data	= &port_data[idx];
135 		serio->dev.parent	= &maceps2_device->dev;
136 	}
137 
138 	return serio;
139 }
140 
141 
142 static int __init maceps2_init(void)
143 {
144 	maceps2_device = platform_device_register_simple("maceps2", -1, NULL, 0);
145 	if (IS_ERR(maceps2_device))
146 		return PTR_ERR(maceps2_device);
147 
148 	port_data[0].port = &mace->perif.ps2.keyb;
149 	port_data[0].irq  = MACEISA_KEYB_IRQ;
150 	port_data[1].port = &mace->perif.ps2.mouse;
151 	port_data[1].irq  = MACEISA_MOUSE_IRQ;
152 
153 	maceps2_port[0] = maceps2_allocate_port(0);
154 	maceps2_port[1] = maceps2_allocate_port(1);
155 	if (!maceps2_port[0] || !maceps2_port[1]) {
156 		kfree(maceps2_port[0]);
157 		kfree(maceps2_port[1]);
158 		platform_device_unregister(maceps2_device);
159 		return -ENOMEM;
160 	}
161 
162 	serio_register_port(maceps2_port[0]);
163 	serio_register_port(maceps2_port[1]);
164 
165 	return 0;
166 }
167 
168 static void __exit maceps2_exit(void)
169 {
170 	serio_unregister_port(maceps2_port[0]);
171 	serio_unregister_port(maceps2_port[1]);
172 	platform_device_unregister(maceps2_device);
173 }
174 
175 module_init(maceps2_init);
176 module_exit(maceps2_exit);
177