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/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_base = (char __iomem *) 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");