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_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");