[PATCH] cfag12864b: fix crash when built-in and no parport present
[linux-2.6.git] / drivers / auxdisplay / cfag12864bfb.c
1 /*
2  *    Filename: cfag12864bfb.c
3  *     Version: 0.1.0
4  * Description: cfag12864b LCD framebuffer driver
5  *     License: GPLv2
6  *     Depends: cfag12864b
7  *
8  *      Author: Copyright (C) Miguel Ojeda Sandonis <maxextreme@gmail.com>
9  *        Date: 2006-10-31
10  *
11  *  This program is free software; you can redistribute it and/or modify
12  *  it under the terms of the GNU General Public License version 2 as
13  *  published by the Free Software Foundation.
14  *
15  *  This program is distributed in the hope that it will be useful,
16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *  GNU General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License
21  *  along with this program; if not, write to the Free Software
22  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23  *
24  */
25
26 #include <linux/init.h>
27 #include <linux/module.h>
28 #include <linux/kernel.h>
29 #include <linux/delay.h>
30 #include <linux/errno.h>
31 #include <linux/fb.h>
32 #include <linux/mm.h>
33 #include <linux/platform_device.h>
34 #include <linux/slab.h>
35 #include <linux/string.h>
36 #include <linux/uaccess.h>
37 #include <linux/cfag12864b.h>
38
39 #define CFAG12864BFB_NAME "cfag12864bfb"
40
41 static struct fb_fix_screeninfo cfag12864bfb_fix __initdata = {
42         .id = "cfag12864b",
43         .type = FB_TYPE_PACKED_PIXELS,
44         .visual = FB_VISUAL_MONO10,
45         .xpanstep = 0,
46         .ypanstep = 0,
47         .ywrapstep = 0,
48         .line_length = CFAG12864B_WIDTH / 8,
49         .accel = FB_ACCEL_NONE,
50 };
51
52 static struct fb_var_screeninfo cfag12864bfb_var __initdata = {
53         .xres = CFAG12864B_WIDTH,
54         .yres = CFAG12864B_HEIGHT,
55         .xres_virtual = CFAG12864B_WIDTH,
56         .yres_virtual = CFAG12864B_HEIGHT,
57         .bits_per_pixel = 1,
58         .red = { 0, 1, 0 },
59         .green = { 0, 1, 0 },
60         .blue = { 0, 1, 0 },
61         .left_margin = 0,
62         .right_margin = 0,
63         .upper_margin = 0,
64         .lower_margin = 0,
65         .vmode = FB_VMODE_NONINTERLACED,
66 };
67
68 static int cfag12864bfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
69 {
70         return vm_insert_page(vma, vma->vm_start,
71                 virt_to_page(cfag12864b_buffer));
72 }
73
74 static struct fb_ops cfag12864bfb_ops = {
75         .owner = THIS_MODULE,
76         .fb_fillrect = cfb_fillrect,
77         .fb_copyarea = cfb_copyarea,
78         .fb_imageblit = cfb_imageblit,
79         .fb_mmap = cfag12864bfb_mmap,
80 };
81
82 static int __init cfag12864bfb_probe(struct platform_device *device)
83 {
84         int ret = -EINVAL;
85         struct fb_info *info = framebuffer_alloc(0, &device->dev);
86
87         if (!info)
88                 goto none;
89
90         info->screen_base = (char __iomem *) cfag12864b_buffer;
91         info->screen_size = CFAG12864B_SIZE;
92         info->fbops = &cfag12864bfb_ops;
93         info->fix = cfag12864bfb_fix;
94         info->var = cfag12864bfb_var;
95         info->pseudo_palette = NULL;
96         info->par = NULL;
97         info->flags = FBINFO_FLAG_DEFAULT;
98
99         if (register_framebuffer(info) < 0)
100                 goto fballoced;
101
102         platform_set_drvdata(device, info);
103
104         printk(KERN_INFO "fb%d: %s frame buffer device\n", info->node,
105                 info->fix.id);
106
107         return 0;
108
109 fballoced:
110         framebuffer_release(info);
111
112 none:
113         return ret;
114 }
115
116 static int cfag12864bfb_remove(struct platform_device *device)
117 {
118         struct fb_info *info = platform_get_drvdata(device);
119
120         if (info) {
121                 unregister_framebuffer(info);
122                 framebuffer_release(info);
123         }
124
125         return 0;
126 }
127
128 static struct platform_driver cfag12864bfb_driver = {
129         .probe  = cfag12864bfb_probe,
130         .remove = cfag12864bfb_remove,
131         .driver = {
132                 .name   = CFAG12864BFB_NAME,
133         },
134 };
135
136 static struct platform_device *cfag12864bfb_device;
137
138 static int __init cfag12864bfb_init(void)
139 {
140         int ret = -EINVAL;
141
142         /* cfag12864b_init() must be called first */
143         if (!cfag12864b_isinited()) {
144                 printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
145                         "cfag12864b is not initialized\n");
146                 goto none;
147         }
148
149         if (cfag12864b_enable()) {
150                 printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
151                         "can't enable cfag12864b refreshing (being used)\n");
152                 return -ENODEV;
153         }
154
155         ret = platform_driver_register(&cfag12864bfb_driver);
156
157         if (!ret) {
158                 cfag12864bfb_device =
159                         platform_device_alloc(CFAG12864BFB_NAME, 0);
160
161                 if (cfag12864bfb_device)
162                         ret = platform_device_add(cfag12864bfb_device);
163                 else
164                         ret = -ENOMEM;
165
166                 if (ret) {
167                         platform_device_put(cfag12864bfb_device);
168                         platform_driver_unregister(&cfag12864bfb_driver);
169                 }
170         }
171
172 none:
173         return ret;
174 }
175
176 static void __exit cfag12864bfb_exit(void)
177 {
178         platform_device_unregister(cfag12864bfb_device);
179         platform_driver_unregister(&cfag12864bfb_driver);
180         cfag12864b_disable();
181 }
182
183 module_init(cfag12864bfb_init);
184 module_exit(cfag12864bfb_exit);
185
186 MODULE_LICENSE("GPL v2");
187 MODULE_AUTHOR("Miguel Ojeda Sandonis <maxextreme@gmail.com>");
188 MODULE_DESCRIPTION("cfag12864b LCD framebuffer driver");