1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) 1999-2001 Vojtech Pavlik
4 */
5
6 /*
7 * 82C710 C&T mouse port chip driver for Linux
8 */
9
10 #include <linux/delay.h>
11 #include <linux/module.h>
12 #include <linux/ioport.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/serio.h>
16 #include <linux/errno.h>
17 #include <linux/err.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20
21 #include <asm/io.h>
22
23 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
24 MODULE_DESCRIPTION("82C710 C&T mouse port chip driver");
25 MODULE_LICENSE("GPL");
26
27 /*
28 * ct82c710 interface
29 */
30
31 #define CT82C710_DEV_IDLE 0x01 /* Device Idle */
32 #define CT82C710_RX_FULL 0x02 /* Device Char received */
33 #define CT82C710_TX_IDLE 0x04 /* Device XMIT Idle */
34 #define CT82C710_RESET 0x08 /* Device Reset */
35 #define CT82C710_INTS_ON 0x10 /* Device Interrupt On */
36 #define CT82C710_ERROR_FLAG 0x20 /* Device Error */
37 #define CT82C710_CLEAR 0x40 /* Device Clear */
38 #define CT82C710_ENABLE 0x80 /* Device Enable */
39
40 #define CT82C710_IRQ 12
41
42 #define CT82C710_DATA ct82c710_iores.start
43 #define CT82C710_STATUS (ct82c710_iores.start + 1)
44
45 static struct serio *ct82c710_port;
46 static struct platform_device *ct82c710_device;
47 static struct resource ct82c710_iores;
48
49 /*
50 * Interrupt handler for the 82C710 mouse port. A character
51 * is waiting in the 82C710.
52 */
53
ct82c710_interrupt(int cpl,void * dev_id)54 static irqreturn_t ct82c710_interrupt(int cpl, void *dev_id)
55 {
56 return serio_interrupt(ct82c710_port, inb(CT82C710_DATA), 0);
57 }
58
59 /*
60 * Wait for device to send output char and flush any input char.
61 */
62
ct82c170_wait(void)63 static int ct82c170_wait(void)
64 {
65 int timeout = 60000;
66
67 while ((inb(CT82C710_STATUS) & (CT82C710_RX_FULL | CT82C710_TX_IDLE | CT82C710_DEV_IDLE))
68 != (CT82C710_DEV_IDLE | CT82C710_TX_IDLE) && timeout) {
69
70 if (inb_p(CT82C710_STATUS) & CT82C710_RX_FULL) inb_p(CT82C710_DATA);
71
72 udelay(1);
73 timeout--;
74 }
75
76 return !timeout;
77 }
78
ct82c710_close(struct serio * serio)79 static void ct82c710_close(struct serio *serio)
80 {
81 if (ct82c170_wait())
82 printk(KERN_WARNING "ct82c710.c: Device busy in close()\n");
83
84 outb_p(inb_p(CT82C710_STATUS) & ~(CT82C710_ENABLE | CT82C710_INTS_ON), CT82C710_STATUS);
85
86 if (ct82c170_wait())
87 printk(KERN_WARNING "ct82c710.c: Device busy in close()\n");
88
89 free_irq(CT82C710_IRQ, NULL);
90 }
91
ct82c710_open(struct serio * serio)92 static int ct82c710_open(struct serio *serio)
93 {
94 unsigned char status;
95 int err;
96
97 err = request_irq(CT82C710_IRQ, ct82c710_interrupt, 0, "ct82c710", NULL);
98 if (err)
99 return err;
100
101 status = inb_p(CT82C710_STATUS);
102
103 status |= (CT82C710_ENABLE | CT82C710_RESET);
104 outb_p(status, CT82C710_STATUS);
105
106 status &= ~(CT82C710_RESET);
107 outb_p(status, CT82C710_STATUS);
108
109 status |= CT82C710_INTS_ON;
110 outb_p(status, CT82C710_STATUS); /* Enable interrupts */
111
112 while (ct82c170_wait()) {
113 printk(KERN_ERR "ct82c710: Device busy in open()\n");
114 status &= ~(CT82C710_ENABLE | CT82C710_INTS_ON);
115 outb_p(status, CT82C710_STATUS);
116 free_irq(CT82C710_IRQ, NULL);
117 return -EBUSY;
118 }
119
120 return 0;
121 }
122
123 /*
124 * Write to the 82C710 mouse device.
125 */
126
ct82c710_write(struct serio * port,unsigned char c)127 static int ct82c710_write(struct serio *port, unsigned char c)
128 {
129 if (ct82c170_wait()) return -1;
130 outb_p(c, CT82C710_DATA);
131 return 0;
132 }
133
134 /*
135 * See if we can find a 82C710 device. Read mouse address.
136 */
137
ct82c710_detect(void)138 static int __init ct82c710_detect(void)
139 {
140 outb_p(0x55, 0x2fa); /* Any value except 9, ff or 36 */
141 outb_p(0xaa, 0x3fa); /* Inverse of 55 */
142 outb_p(0x36, 0x3fa); /* Address the chip */
143 outb_p(0xe4, 0x3fa); /* 390/4; 390 = config address */
144 outb_p(0x1b, 0x2fa); /* Inverse of e4 */
145 outb_p(0x0f, 0x390); /* Write index */
146 if (inb_p(0x391) != 0xe4) /* Config address found? */
147 return -ENODEV; /* No: no 82C710 here */
148
149 outb_p(0x0d, 0x390); /* Write index */
150 ct82c710_iores.start = inb_p(0x391) << 2; /* Get mouse I/O address */
151 ct82c710_iores.end = ct82c710_iores.start + 1;
152 ct82c710_iores.flags = IORESOURCE_IO;
153 outb_p(0x0f, 0x390);
154 outb_p(0x0f, 0x391); /* Close config mode */
155
156 return 0;
157 }
158
ct82c710_probe(struct platform_device * dev)159 static int ct82c710_probe(struct platform_device *dev)
160 {
161 ct82c710_port = kzalloc(sizeof(struct serio), GFP_KERNEL);
162 if (!ct82c710_port)
163 return -ENOMEM;
164
165 ct82c710_port->id.type = SERIO_8042;
166 ct82c710_port->dev.parent = &dev->dev;
167 ct82c710_port->open = ct82c710_open;
168 ct82c710_port->close = ct82c710_close;
169 ct82c710_port->write = ct82c710_write;
170 strscpy(ct82c710_port->name, "C&T 82c710 mouse port",
171 sizeof(ct82c710_port->name));
172 snprintf(ct82c710_port->phys, sizeof(ct82c710_port->phys),
173 "isa%16llx/serio0", (unsigned long long)CT82C710_DATA);
174
175 serio_register_port(ct82c710_port);
176
177 printk(KERN_INFO "serio: C&T 82c710 mouse port at %#llx irq %d\n",
178 (unsigned long long)CT82C710_DATA, CT82C710_IRQ);
179
180 return 0;
181 }
182
ct82c710_remove(struct platform_device * dev)183 static int ct82c710_remove(struct platform_device *dev)
184 {
185 serio_unregister_port(ct82c710_port);
186
187 return 0;
188 }
189
190 static struct platform_driver ct82c710_driver = {
191 .driver = {
192 .name = "ct82c710",
193 },
194 .probe = ct82c710_probe,
195 .remove = ct82c710_remove,
196 };
197
198
ct82c710_init(void)199 static int __init ct82c710_init(void)
200 {
201 int error;
202
203 error = ct82c710_detect();
204 if (error)
205 return error;
206
207 error = platform_driver_register(&ct82c710_driver);
208 if (error)
209 return error;
210
211 ct82c710_device = platform_device_alloc("ct82c710", -1);
212 if (!ct82c710_device) {
213 error = -ENOMEM;
214 goto err_unregister_driver;
215 }
216
217 error = platform_device_add_resources(ct82c710_device, &ct82c710_iores, 1);
218 if (error)
219 goto err_free_device;
220
221 error = platform_device_add(ct82c710_device);
222 if (error)
223 goto err_free_device;
224
225 return 0;
226
227 err_free_device:
228 platform_device_put(ct82c710_device);
229 err_unregister_driver:
230 platform_driver_unregister(&ct82c710_driver);
231 return error;
232 }
233
ct82c710_exit(void)234 static void __exit ct82c710_exit(void)
235 {
236 platform_device_unregister(ct82c710_device);
237 platform_driver_unregister(&ct82c710_driver);
238 }
239
240 module_init(ct82c710_init);
241 module_exit(ct82c710_exit);
242