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
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
/*
* 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/slab.h>
#include <linux/serial_core.h>
#include <linux/serial_8250.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/nwpserial.h>
struct of_serial_info {
int type;
int line;
};
/*
* Fill a struct uart_port for a given device node
*/
static int __devinit of_platform_serial_setup(struct platform_device *ofdev,
int type, struct uart_port *port)
{
struct resource resource;
struct device_node *np = ofdev->dev.of_node;
const __be32 *clk, *spd;
const __be32 *prop;
int ret, prop_size;
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;
/* Check for shifted address mapping */
prop = of_get_property(np, "reg-offset", &prop_size);
if (prop && (prop_size == sizeof(u32)))
port->mapbase += be32_to_cpup(prop);
/* Check for registers offset within the devices address range */
prop = of_get_property(np, "reg-shift", &prop_size);
if (prop && (prop_size == sizeof(u32)))
port->regshift = be32_to_cpup(prop);
port->irq = irq_of_parse_and_map(np, 0);
port->iotype = UPIO_MEM;
port->type = type;
port->uartclk = be32_to_cpup(clk);
port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
| UPF_FIXED_PORT | UPF_FIXED_TYPE;
port->dev = &ofdev->dev;
/* If current-speed was set, then try not to change it. */
if (spd)
port->custom_divisor = be32_to_cpup(clk) / (16 * (be32_to_cpup(spd)));
return 0;
}
/*
* Try to register a serial port
*/
static struct of_device_id of_platform_serial_table[];
static int __devinit of_platform_serial_probe(struct platform_device *ofdev)
{
const struct of_device_id *match;
struct of_serial_info *info;
struct uart_port port;
int port_type;
int ret;
match = of_match_device(of_platform_serial_table, &ofdev->dev);
if (!match)
return -EINVAL;
if (of_find_property(ofdev->dev.of_node, "used-by-rtas", NULL))
return -EBUSY;
info = kmalloc(sizeof(*info), GFP_KERNEL);
if (info == NULL)
return -ENOMEM;
port_type = (unsigned long)match->data;
ret = of_platform_serial_setup(ofdev, port_type, &port);
if (ret)
goto out;
switch (port_type) {
#ifdef CONFIG_SERIAL_8250
case PORT_8250 ... PORT_MAX_8250:
ret = serial8250_register_port(&port);
break;
#endif
#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
case PORT_NWPSERIAL:
ret = nwpserial_register_port(&port);
break;
#endif
default:
/* need to add code for these */
case PORT_UNKNOWN:
dev_info(&ofdev->dev, "Unknown serial port found, ignored\n");
ret = -ENODEV;
break;
}
if (ret < 0)
goto out;
info->type = port_type;
info->line = ret;
dev_set_drvdata(&ofdev->dev, info);
return 0;
out:
kfree(info);
irq_dispose_mapping(port.irq);
return ret;
}
/*
* Release a line
*/
static int of_platform_serial_remove(struct platform_device *ofdev)
{
struct of_serial_info *info = dev_get_drvdata(&ofdev->dev);
switch (info->type) {
#ifdef CONFIG_SERIAL_8250
case PORT_8250 ... PORT_MAX_8250:
serial8250_unregister_port(info->line);
break;
#endif
#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
case PORT_NWPSERIAL:
nwpserial_unregister_port(info->line);
break;
#endif
default:
/* need to add code for these */
break;
}
kfree(info);
return 0;
}
/*
* A few common types, add more as needed.
*/
static struct of_device_id __devinitdata of_platform_serial_table[] = {
{ .compatible = "ns8250", .data = (void *)PORT_8250, },
{ .compatible = "ns16450", .data = (void *)PORT_16450, },
{ .compatible = "ns16550a", .data = (void *)PORT_16550A, },
{ .compatible = "ns16550", .data = (void *)PORT_16550, },
{ .compatible = "ns16750", .data = (void *)PORT_16750, },
{ .compatible = "ns16850", .data = (void *)PORT_16850, },
#ifdef CONFIG_SERIAL_OF_PLATFORM_NWPSERIAL
{ .compatible = "ibm,qpace-nwp-serial",
.data = (void *)PORT_NWPSERIAL, },
#endif
{ .type = "serial", .data = (void *)PORT_UNKNOWN, },
{ /* end of list */ },
};
static struct platform_driver of_platform_serial_driver = {
.driver = {
.name = "of_serial",
.owner = THIS_MODULE,
.of_match_table = of_platform_serial_table,
},
.probe = of_platform_serial_probe,
.remove = of_platform_serial_remove,
};
static int __init of_platform_serial_init(void)
{
return platform_driver_register(&of_platform_serial_driver);
}
module_init(of_platform_serial_init);
static void __exit of_platform_serial_exit(void)
{
return platform_driver_unregister(&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");
|
