drivers/auxdisplay/cfag12864bfb.c

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