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         vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
  55
  56         return vm_map_pages_zero(vma, &pages, 1);
  57 }
  58
  59 static const struct fb_ops cfag12864bfb_ops = {
  60         .owner = THIS_MODULE,
  61         __FB_DEFAULT_SYSMEM_OPS_RDWR,
  62         __FB_DEFAULT_SYSMEM_OPS_DRAW,
  63         .fb_mmap = cfag12864bfb_mmap,
  64 };
  65
  66 static int cfag12864bfb_probe(struct platform_device *device)
  67 {
  68         int ret = -EINVAL;
  69         struct fb_info *info = framebuffer_alloc(0, &device->dev);
  70
  71         if (!info)
  72                 goto none;
  73
  74         info->flags = FBINFO_VIRTFB;
  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 void 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
 109 static struct platform_driver cfag12864bfb_driver = {
 110         .probe  = cfag12864bfb_probe,
 111         .remove = cfag12864bfb_remove,
 112         .driver = {
 113                 .name   = CFAG12864BFB_NAME,
 114         },
 115 };
 116
 117 static struct platform_device *cfag12864bfb_device;
 118
 119 static int __init cfag12864bfb_init(void)
 120 {
 121         int ret = -EINVAL;
 122
 123         /* cfag12864b_init() must be called first */
 124         if (!cfag12864b_isinited()) {
 125                 printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
 126                         "cfag12864b is not initialized\n");
 127                 goto none;
 128         }
 129
 130         if (cfag12864b_enable()) {
 131                 printk(KERN_ERR CFAG12864BFB_NAME ": ERROR: "
 132                         "can't enable cfag12864b refreshing (being used)\n");
 133                 return -ENODEV;
 134         }
 135
 136         ret = platform_driver_register(&cfag12864bfb_driver);
 137
 138         if (!ret) {
 139                 cfag12864bfb_device =
 140                         platform_device_alloc(CFAG12864BFB_NAME, 0);
 141
 142                 if (cfag12864bfb_device)
 143                         ret = platform_device_add(cfag12864bfb_device);
 144                 else
 145                         ret = -ENOMEM;
 146
 147                 if (ret) {
 148                         platform_device_put(cfag12864bfb_device);
 149                         platform_driver_unregister(&cfag12864bfb_driver);
 150                 }
 151         }
 152
 153 none:
 154         return ret;
 155 }
 156
 157 static void __exit cfag12864bfb_exit(void)
 158 {
 159         platform_device_unregister(cfag12864bfb_device);
 160         platform_driver_unregister(&cfag12864bfb_driver);
 161         cfag12864b_disable();
 162 }
 163
 164 module_init(cfag12864bfb_init);
 165 module_exit(cfag12864bfb_exit);
 166
 167 MODULE_LICENSE("GPL v2");
 168 MODULE_AUTHOR("Miguel Ojeda <ojeda@kernel.org>");
 169 MODULE_DESCRIPTION("cfag12864b LCD framebuffer driver");