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 
83 	if (register_framebuffer(info) < 0)
84 		goto fballoced;
85 
86 	platform_set_drvdata(device, info);
87 
88 	fb_info(info, "%s frame buffer device\n", info->fix.id);
89 
90 	return 0;
91 
92 fballoced:
93 	framebuffer_release(info);
94 
95 none:
96 	return ret;
97 }
98 
99 static int cfag12864bfb_remove(struct platform_device *device)
100 {
101 	struct fb_info *info = platform_get_drvdata(device);
102 
103 	if (info) {
104 		unregister_framebuffer(info);
105 		framebuffer_release(info);
106 	}
107 
108 	return 0;
109 }
110 
111 static struct platform_driver cfag12864bfb_driver = {
112 	.probe	= cfag12864bfb_probe,
113 	.remove = cfag12864bfb_remove,
114 	.driver = {
115 		.name	= CFAG12864BFB_NAME,
116 	},
117 };
118 
119 static struct platform_device *cfag12864bfb_device;
120 
121 static int __init cfag12864bfb_init(void)
122 {
123 	int ret = -EINVAL;
124 
125 	/* cfag12864b_init() must be called first */
126 	if (!cfag12864b_isinited()) {
127 		printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
128 			"cfag12864b is not initialized\n");
129 		goto none;
130 	}
131 
132 	if (cfag12864b_enable()) {
133 		printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
134 			"can't enable cfag12864b refreshing (being used)\n");
135 		return -ENODEV;
136 	}
137 
138 	ret = platform_driver_register(&cfag12864bfb_driver);
139 
140 	if (!ret) {
141 		cfag12864bfb_device =
142 			platform_device_alloc(CFAG12864BFB_NAME, 0);
143 
144 		if (cfag12864bfb_device)
145 			ret = platform_device_add(cfag12864bfb_device);
146 		else
147 			ret = -ENOMEM;
148 
149 		if (ret) {
150 			platform_device_put(cfag12864bfb_device);
151 			platform_driver_unregister(&cfag12864bfb_driver);
152 		}
153 	}
154 
155 none:
156 	return ret;
157 }
158 
159 static void __exit cfag12864bfb_exit(void)
160 {
161 	platform_device_unregister(cfag12864bfb_device);
162 	platform_driver_unregister(&cfag12864bfb_driver);
163 	cfag12864b_disable();
164 }
165 
166 module_init(cfag12864bfb_init);
167 module_exit(cfag12864bfb_exit);
168 
169 MODULE_LICENSE("GPL v2");
170 MODULE_AUTHOR("Miguel Ojeda <ojeda@kernel.org>");
171 MODULE_DESCRIPTION("cfag12864b LCD framebuffer driver");
172