tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * vio driver interface to hvc_console.c
3 *
4 * This code was moved here to allow the remaing code to be reused as a
5 * generic polling mode with semi-reliable transport driver core to the
6 * console and tty subsystems.
7 *
8 *
9 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
10 * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
11 * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
12 * Copyright (C) 2004 IBM Corporation
13 *
14 * Additional Author(s):
15 * Ryan S. Arnold <rsa@us.ibm.com>
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
21 *
22 * This program is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License
28 * along with this program; if not, write to the Free Software
29 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30 */
31
32#include <linux/types.h>
33#include <linux/init.h>
34
35#include <asm/hvconsole.h>
36#include <asm/vio.h>
37#include <asm/prom.h>
38#include <asm/firmware.h>
39
40#include "hvc_console.h"
41
42char hvc_driver_name[] = "hvc_console";
43
44static struct vio_device_id hvc_driver_table[] __devinitdata = {
45 {"serial", "hvterm1"},
46 { "", "" }
47};
48MODULE_DEVICE_TABLE(vio, hvc_driver_table);
49
50static int filtered_get_chars(uint32_t vtermno, char *buf, int count)
51{
52 unsigned long got;
53 int i;
54
55 /*
56 * Vio firmware will read up to SIZE_VIO_GET_CHARS at its own discretion
57 * so we play safe and avoid the situation where got > count which could
58 * overload the flip buffer.
59 */
60 if (count < SIZE_VIO_GET_CHARS)
61 return -EAGAIN;
62
63 got = hvc_get_chars(vtermno, buf, count);
64
65 /*
66 * Work around a HV bug where it gives us a null
67 * after every \r. -- paulus
68 */
69 for (i = 1; i < got; ++i) {
70 if (buf[i] == 0 && buf[i-1] == '\r') {
71 --got;
72 if (i < got)
73 memmove(&buf[i], &buf[i+1],
74 got - i);
75 }
76 }
77 return got;
78}
79
80static struct hv_ops hvc_get_put_ops = {
81 .get_chars = filtered_get_chars,
82 .put_chars = hvc_put_chars,
83};
84
85static int __devinit hvc_vio_probe(struct vio_dev *vdev,
86 const struct vio_device_id *id)
87{
88 struct hvc_struct *hp;
89
90 /* probed with invalid parameters. */
91 if (!vdev || !id)
92 return -EPERM;
93
94 hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops,
95 MAX_VIO_PUT_CHARS);
96 if (IS_ERR(hp))
97 return PTR_ERR(hp);
98 dev_set_drvdata(&vdev->dev, hp);
99
100 return 0;
101}
102
103static int __devexit hvc_vio_remove(struct vio_dev *vdev)
104{
105 struct hvc_struct *hp = dev_get_drvdata(&vdev->dev);
106
107 return hvc_remove(hp);
108}
109
110static struct vio_driver hvc_vio_driver = {
111 .id_table = hvc_driver_table,
112 .probe = hvc_vio_probe,
113 .remove = hvc_vio_remove,
114 .driver = {
115 .name = hvc_driver_name,
116 .owner = THIS_MODULE,
117 }
118};
119
120static int hvc_vio_init(void)
121{
122 int rc;
123
124 if (firmware_has_feature(FW_FEATURE_ISERIES))
125 return -EIO;
126
127 /* Register as a vio device to receive callbacks */
128 rc = vio_register_driver(&hvc_vio_driver);
129
130 return rc;
131}
132module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
133
134static void hvc_vio_exit(void)
135{
136 vio_unregister_driver(&hvc_vio_driver);
137}
138module_exit(hvc_vio_exit);
139
140/* the device tree order defines our numbering */
141static int hvc_find_vtys(void)
142{
143 struct device_node *vty;
144 int num_found = 0;
145
146 for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
147 vty = of_find_node_by_name(vty, "vty")) {
148 const uint32_t *vtermno;
149
150 /* We have statically defined space for only a certain number
151 * of console adapters.
152 */
153 if (num_found >= MAX_NR_HVC_CONSOLES)
154 break;
155
156 vtermno = get_property(vty, "reg", NULL);
157 if (!vtermno)
158 continue;
159
160 if (device_is_compatible(vty, "hvterm1")) {
161 hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops);
162 ++num_found;
163 }
164 }
165
166 return num_found;
167}
168console_initcall(hvc_find_vtys);