1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *    Filename: cfag12864bfb.c
4  *     Version: 0.1.0
5  * Description: cfag12864b LCD framebuffer driver
6  *     Depends: cfag12864b
7  *
8  *      Author: Copyright (C) Miguel Ojeda <ojeda@kernel.org>
9  *        Date: 2006-10-31
10  */
11 
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/fb.h>
17 #include <linux/mm.h>
18 #include <linux/platform_device.h>
19 #include <linux/cfag12864b.h>
20 
21 #define CFAG12864BFB_NAME "cfag12864bfb"
22 
23 static const struct fb_fix_screeninfo cfag12864bfb_fix = {
24 	.id = "cfag12864b",
25 	.type = FB_TYPE_PACKED_PIXELS,
26 	.visual = FB_VISUAL_MONO10,
27 	.xpanstep = 0,
28 	.ypanstep = 0,
29 	.ywrapstep = 0,
30 	.line_length = CFAG12864B_WIDTH / 8,
31 	.accel = FB_ACCEL_NONE,
32 };
33 
34 static const struct fb_var_screeninfo cfag12864bfb_var = {
35 	.xres = CFAG12864B_WIDTH,
36 	.yres = CFAG12864B_HEIGHT,
37 	.xres_virtual = CFAG12864B_WIDTH,
38 	.yres_virtual = CFAG12864B_HEIGHT,
39 	.bits_per_pixel = 1,
40 	.red = { 0, 1, 0 },
41 	.green = { 0, 1, 0 },
42 	.blue = { 0, 1, 0 },
43 	.left_margin = 0,
44 	.right_margin = 0,
45 	.upper_margin = 0,
46 	.lower_margin = 0,
47 	.vmode = FB_VMODE_NONINTERLACED,
48 };
49 
50 static int cfag12864bfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
51 {
52 	struct page *pages = virt_to_page(cfag12864b_buffer);
53 
54 	return vm_map_pages_zero(vma, &pages, 1);
55 }
56 
57 static const struct fb_ops cfag12864bfb_ops = {
58 	.owner = THIS_MODULE,
59 	.fb_read = fb_sys_read,
60 	.fb_write = fb_sys_write,
61 	.fb_fillrect = sys_fillrect,
62 	.fb_copyarea = sys_copyarea,
63 	.fb_imageblit = sys_imageblit,
64 	.fb_mmap = cfag12864bfb_mmap,
65 };
66 
67 static int cfag12864bfb_probe(struct platform_device *device)
68 {
69 	int ret = -EINVAL;
70 	struct fb_info *info = framebuffer_alloc(0, &device->dev);
71 
72 	if (!info)
73 		goto none;
74 
75 	info->screen_buffer = cfag12864b_buffer;
76 	info->screen_size = CFAG12864B_SIZE;
77 	info->fbops = &cfag12864bfb_ops;
78 	info->fix = cfag12864bfb_fix;
79 	info->var = cfag12864bfb_var;
80 	info->pseudo_palette = NULL;
81 	info->par = NULL;
82 	info->flags = FBINFO_FLAG_DEFAULT;
83 
84 	if (register_framebuffer(info) < 0)
85 		goto fballoced;
86 
87 	platform_set_drvdata(device, info);
88 
89 	fb_info(info, "%s frame buffer device\n", info->fix.id);
90 
91 	return 0;
92 
93 fballoced:
94 	framebuffer_release(info);
95 
96 none:
97 	return ret;
98 }
99 
100 static int cfag12864bfb_remove(struct platform_device *device)
101 {
102 	struct fb_info *info = platform_get_drvdata(device);
103 
104 	if (info) {
105 		unregister_framebuffer(info);
106 		framebuffer_release(info);
107 	}
108 
109 	return 0;
110 }
111 
112 static struct platform_driver cfag12864bfb_driver = {
113 	.probe	= cfag12864bfb_probe,
114 	.remove = cfag12864bfb_remove,
115 	.driver = {
116 		.name	= CFAG12864BFB_NAME,
117 	},
118 };
119 
120 static struct platform_device *cfag12864bfb_device;
121 
122 static int __init cfag12864bfb_init(void)
123 {
124 	int ret = -EINVAL;
125 
126 	/* cfag12864b_init() must be called first */
127 	if (!cfag12864b_isinited()) {
128 		printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
129 			"cfag12864b is not initialized\n");
130 		goto none;
131 	}
132 
133 	if (cfag12864b_enable()) {
134 		printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
135 			"can't enable cfag12864b refreshing (being used)\n");
136 		return -ENODEV;
137 	}
138 
139 	ret = platform_driver_register(&cfag12864bfb_driver);
140 
141 	if (!ret) {
142 		cfag12864bfb_device =
143 			platform_device_alloc(CFAG12864BFB_NAME, 0);
144 
145 		if (cfag12864bfb_device)
146 			ret = platform_device_add(cfag12864bfb_device);
147 		else
148 			ret = -ENOMEM;
149 
150 		if (ret) {
151 			platform_device_put(cfag12864bfb_device);
152 			platform_driver_unregister(&cfag12864bfb_driver);
153 		}
154 	}
155 
156 none:
157 	return ret;
158 }
159 
160 static void __exit cfag12864bfb_exit(void)
161 {
162 	platform_device_unregister(cfag12864bfb_device);
163 	platform_driver_unregister(&cfag12864bfb_driver);
164 	cfag12864b_disable();
165 }
166 
167 module_init(cfag12864bfb_init);
168 module_exit(cfag12864bfb_exit);
169 
170 MODULE_LICENSE("GPL v2");
171 MODULE_AUTHOR("Miguel Ojeda <ojeda@kernel.org>");
172 MODULE_DESCRIPTION("cfag12864b LCD framebuffer driver");
173