1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
/*
* Serial Port driver for Open Firmware platform devices
*
* Copyright (C) 2006 Arnd Bergmann <arnd@arndb.de>, IBM Corp.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/serial_core.h>
#include <linux/serial_8250.h>
#include <asm/of_platform.h>
#include <asm/prom.h>
/*
* Fill a struct uart_port for a given device node
*/
static int __devinit of_platform_serial_setup(struct of_device *ofdev,
int type, struct uart_port *port)
{
struct resource resource;
struct device_node *np = ofdev->node;
const unsigned int *clk, *spd;
int ret;
memset(port, 0, sizeof *port);
spd = of_get_property(np, "current-speed", NULL);
clk = of_get_property(np, "clock-frequency", NULL);
if (!clk) {
dev_warn(&ofdev->dev, "no clock-frequency property set\n");
return -ENODEV;
}
ret = of_address_to_resource(np, 0, &resource);
if (ret) {
dev_warn(&ofdev->dev, "invalid address\n");
return ret;
}
spin_lock_init(&port->lock);
port->mapbase = resource.start;
port->irq = irq_of_parse_and_map(np, 0);
port->iotype = UPIO_MEM;
port->type = type;
port->uartclk = *clk;
port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP;
port->dev = &ofdev->dev;
port->custom_divisor = *clk / (16 * (*spd));
return 0;
}
/*
* Try to register a serial port
*/
static int __devinit of_platform_serial_probe(struct of_device *ofdev,
const struct of_device_id *id)
{
struct uart_port port;
int port_type;
int ret;
if (of_find_property(ofdev->node, "used-by-rtas", NULL))
return -EBUSY;
port_type = (unsigned long)id->data;
ret = of_platform_serial_setup(ofdev, port_type, &port);
if (ret)
goto out;
switch (port_type) {
case PORT_UNKNOWN:
dev_info(&ofdev->dev, "Unknown serial port found, "
"attempting to use 8250 driver\n");
/* fallthrough */
case PORT_8250 ... PORT_MAX_8250:
ret = serial8250_register_port(&port);
break;
default:
/* need to add code for these */
ret = -ENODEV;
break;
}
if (ret < 0)
goto out;
ofdev->dev.driver_data = (void *)(unsigned long)ret;
return 0;
out:
irq_dispose_mapping(port.irq);
return ret;
}
/*
* Release a line
*/
static int of_platform_serial_remove(struct of_device *ofdev)
{
int line = (unsigned long)ofdev->dev.driver_data;
serial8250_unregister_port(line);
return 0;
}
/*
* A few common types, add more as needed.
*/
static struct of_device_id __devinitdata of_platform_serial_table[] = {
{ .type = "serial", .compatible = "ns8250", .data = (void *)PORT_8250, },
{ .type = "serial", .compatible = "ns16450", .data = (void *)PORT_16450, },
{ .type = "serial", .compatible = "ns16550", .data = (void *)PORT_16550, },
{ .type = "serial", .compatible = "ns16750", .data = (void *)PORT_16750, },
{ .type = "serial", .data = (void *)PORT_UNKNOWN, },
{ /* end of list */ },
};
static struct of_platform_driver __devinitdata of_platform_serial_driver = {
.owner = THIS_MODULE,
.name = "of_serial",
.probe = of_platform_serial_probe,
.remove = of_platform_serial_remove,
.match_table = of_platform_serial_table,
};
static int __init of_platform_serial_init(void)
{
return of_register_platform_driver(&of_platform_serial_driver);
}
module_init(of_platform_serial_init);
static void __exit of_platform_serial_exit(void)
{
return of_unregister_platform_driver(&of_platform_serial_driver);
};
module_exit(of_platform_serial_exit);
MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Serial Port driver for Open Firmware platform devices");
|
