]> err.no Git - linux-2.6/blob - drivers/misc/hdpuftrs/hdpu_nexus.c
[POWERPC] Sky Cpu and Nexus: check for create_proc_entry ret code
[linux-2.6] / drivers / misc / hdpuftrs / hdpu_nexus.c
1 /*
2  *      Sky Nexus Register Driver
3  *
4  *      Copyright (C) 2002 Brian Waite
5  *
6  *      This driver allows reading the Nexus register
7  *      It exports the /proc/sky_chassis_id and also
8  *      /proc/sky_slot_id pseudo-file for status information.
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  *
15  */
16
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/proc_fs.h>
20 #include <linux/hdpu_features.h>
21
22 #include <linux/platform_device.h>
23 #include <asm/io.h>
24
25 static int hdpu_nexus_probe(struct platform_device *pdev);
26 static int hdpu_nexus_remove(struct platform_device *pdev);
27
28 static struct proc_dir_entry *hdpu_slot_id;
29 static struct proc_dir_entry *hdpu_chassis_id;
30 static int slot_id = -1;
31 static int chassis_id = -1;
32
33 static struct platform_driver hdpu_nexus_driver = {
34         .probe = hdpu_nexus_probe,
35         .remove = hdpu_nexus_remove,
36         .driver = {
37                 .name = HDPU_NEXUS_NAME,
38         },
39 };
40
41 int hdpu_slot_id_read(char *buffer, char **buffer_location, off_t offset,
42                       int buffer_length, int *zero, void *ptr)
43 {
44         if (offset > 0)
45                 return 0;
46
47         return sprintf(buffer, "%d\n", slot_id);
48 }
49
50 int hdpu_chassis_id_read(char *buffer, char **buffer_location, off_t offset,
51                          int buffer_length, int *zero, void *ptr)
52 {
53         if (offset > 0)
54                 return 0;
55
56         return sprintf(buffer, "%d\n", chassis_id);
57 }
58
59 static int hdpu_nexus_probe(struct platform_device *pdev)
60 {
61         struct resource *res;
62         int *nexus_id_addr;
63
64         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
65         if (!res) {
66                 printk(KERN_ERR "sky_nexus: "
67                        "Invalid memory resource.\n");
68                 return -EINVAL;
69         }
70         nexus_id_addr = ioremap(res->start,
71                                 (unsigned long)(res->end - res->start));
72         if (nexus_id_addr) {
73                 slot_id = (*nexus_id_addr >> 8) & 0x1f;
74                 chassis_id = *nexus_id_addr & 0xff;
75                 iounmap(nexus_id_addr);
76         } else {
77                 printk(KERN_ERR "sky_nexus: Could not map slot id\n");
78         }
79
80         hdpu_slot_id = create_proc_entry("sky_slot_id", 0666, &proc_root);
81         if (!hdpu_slot_id) {
82                 printk(KERN_WARNING "sky_nexus: "
83                        "Unable to create proc dir entry: sky_slot_id\n");
84         } else {
85                 hdpu_slot_id->read_proc = hdpu_slot_id_read;
86         }
87
88         hdpu_chassis_id = create_proc_entry("sky_chassis_id", 0666, &proc_root);
89         if (!hdpu_chassis_id) {
90                 printk(KERN_WARNING "sky_nexus: "
91                        "Unable to create proc dir entry: sky_chassis_id\n");
92         } else {
93                 hdpu_chassis_id->read_proc = hdpu_chassis_id_read;
94         }
95
96         return 0;
97 }
98
99 static int hdpu_nexus_remove(struct platform_device *pdev)
100 {
101         slot_id = -1;
102         chassis_id = -1;
103
104         remove_proc_entry("sky_slot_id", &proc_root);
105         remove_proc_entry("sky_chassis_id", &proc_root);
106
107         hdpu_slot_id = 0;
108         hdpu_chassis_id = 0;
109
110         return 0;
111 }
112
113 static int __init nexus_init(void)
114 {
115         return platform_driver_register(&hdpu_nexus_driver);
116 }
117
118 static void __exit nexus_exit(void)
119 {
120         platform_driver_unregister(&hdpu_nexus_driver);
121 }
122
123 module_init(nexus_init);
124 module_exit(nexus_exit);
125
126 MODULE_AUTHOR("Brian Waite");
127 MODULE_LICENSE("GPL");